WorldWideScience

Sample records for monolithic power structure

  1. Anisotropically structured magnetic aerogel monoliths

    Science.gov (United States)

    Heiligtag, Florian J.; Airaghi Leccardi, Marta J. I.; Erdem, Derya; Süess, Martin J.; Niederberger, Markus

    2014-10-01

    Texturing of magnetic ceramics and composites by aligning and fixing of colloidal particles in a magnetic field is a powerful strategy to induce anisotropic chemical, physical and especially mechanical properties into bulk materials. If porosity could be introduced, anisotropically structured magnetic materials would be the perfect supports for magnetic separations in biotechnology or for magnetic field-assisted chemical reactions. Aerogels, combining high porosity with nanoscale structural features, offer an exceptionally large surface area, but they are difficult to magnetically texture. Here we present the preparation of anatase-magnetite aerogel monoliths via the assembly of preformed nanocrystallites. Different approaches are proposed to produce macroscopic bodies with gradient-like magnetic segmentation or with strongly anisotropic magnetic texture.Texturing of magnetic ceramics and composites by aligning and fixing of colloidal particles in a magnetic field is a powerful strategy to induce anisotropic chemical, physical and especially mechanical properties into bulk materials. If porosity could be introduced, anisotropically structured magnetic materials would be the perfect supports for magnetic separations in biotechnology or for magnetic field-assisted chemical reactions. Aerogels, combining high porosity with nanoscale structural features, offer an exceptionally large surface area, but they are difficult to magnetically texture. Here we present the preparation of anatase-magnetite aerogel monoliths via the assembly of preformed nanocrystallites. Different approaches are proposed to produce macroscopic bodies with gradient-like magnetic segmentation or with strongly anisotropic magnetic texture. Electronic supplementary information (ESI) available: Digital photographs of dispersions and gels with different water-to-ethanol ratios; magnetic measurements of an anatase aerogel containing 0.25 mol% Fe3O4 nanoparticles; XRD patterns of the iron oxide and

  2. Monolithic fuel cell based power source for burst power generation

    Science.gov (United States)

    Fee, D. C.; Blackburn, P. E.; Busch, D. E.; Dees, D. W.; Dusek, J.; Easler, T. E.; Ellingson, W. A.; Flandermeyer, B. K.; Fousek, R. J.; Heiberger, J. J.

    A unique fuel cell coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The monolithic fuel cell looks attractive for space applications and represents a quantum jump in fuel cell technology. Such a breakthrough in design is the enabling technology for lightweight, low volume power sources for space based pulse power systems. The monolith is unique among fuel cells in being an all solid state device. The capability for miniaturization, inherent in solid state devices, gives the low volume required for space missions. In addition, the solid oxide fuel cell technology employed in the monolith has high temperature reject heat and can be operated in either closed or open cycles. Both these features are attractive for integration into a burst power system.

  3. Hierarchically Structured Monolithic ZSM-5 through Macroporous Silica Gel Zeolitization

    Institute of Scientific and Technical Information of China (English)

    Lei Qian; Zhao Tianbo; Li Fengyan; Zong Baoning; Tong Yangchuan

    2006-01-01

    The hierarchically structured ZSM-5 monolith was prepared through transforming the skeletons of the macroporous silica gel into ZSM-5 by the steam-assisted conversion method. The morphology and monolithic shapes of macroporous silica gel were well preserved. The hierarchically structured ZSM-5 monolith exhibited the hierarchical porosity, with mesopores and macropores existing inside the macroporous silica gel, and micropores formed by the ZSM-5. The products have been characterized properly by using the XRD, SEM and N2 adsorption-desorption methods.

  4. Increased thermal conductivity monolithic zeolite structures

    Science.gov (United States)

    Klett, James; Klett, Lynn; Kaufman, Jonathan

    2008-11-25

    A monolith comprises a zeolite, a thermally conductive carbon, and a binder. The zeolite is included in the form of beads, pellets, powders and mixtures thereof. The thermally conductive carbon can be carbon nano-fibers, diamond or graphite which provide thermal conductivities in excess of about 100 W/mK to more than 1,000 W/mK. A method of preparing a zeolite monolith includes the steps of mixing a zeolite dispersion in an aqueous colloidal silica binder with a dispersion of carbon nano-fibers in water followed by dehydration and curing of the binder is given.

  5. Analysis of monolithic integrated master oscillator power amplifiers

    Science.gov (United States)

    Mehuys, David; Welch, David F.; Waarts, Robert G.; Parke, Ross; Hardy, Amos; Streifer, William

    1991-07-01

    An analysis of a novel, monolithic integrated master oscillator power amplifier (M-MOPA) is presented. The M-MOPA consists of a DBR master oscillator which injects power into a linear chain of amplifiers and detuned second-order grating output couplers. The analysis self-consistently includes amplified spontaneous emission buildup and residual reflections throughout the amplifier stages. It predicts that output powers in excess of 1 W can be expected from a single-lateral-mode waveguide multistage amplifier less than 1 cm in length, injected with less than 15 mW of input power. In addition to the signal gain of more than 25 dB, the signal-to-noise ratio at 1-W output exceeds 15 dB. Because of the small reflections associated with the grating output couplers, and gain saturation by the injected signal, the amplifier self-oscillation threshold is suppressed to current densities above 15 kA/sq cm.

  6. GaN Monolithic Power Amplifiers for Microwave Backhaul Applications

    Directory of Open Access Journals (Sweden)

    Roberto Quaglia

    2016-06-01

    Full Text Available Gallium nitride integrated technology is very promising not only for wireless applications at mobile frequencies (below 6 GHz but also for network backhaul radiolink deployment, now under deep revision for the incoming 5G generation of mobile communications. This contribution presents three linear power amplifiers realized on 0.25 μ m Gallium Nitride on Silicon Carbide monolithic integrated circuits for microwave backhaul applications: two combined power amplifiers working in the backhaul band around 7 GHz, and a more challenging third one working in the higher 15 GHz band. Architectures and main design steps are described, highlighting the pros and cons of Gallium Nitride with respect to the reference technology which, for these applications, is represented by gallium arsenide.

  7. A novel design for monolithic interconnected modules (MIMs) for thermophotovoltaic (TPV) power conversion

    Energy Technology Data Exchange (ETDEWEB)

    Ward, J.S.; Duda, A.; Wanlass, M.W. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1997-06-01

    The design for the fabrication of Monolithic Interconnected Modules (MIMs) for thermophotovoltaic (TPV) power conversion described in this paper utilizes a novel, interdigitated contacting scheme that increases the flexibility in the size of the component cells and hence the output current and voltage of the module. This flexibility is gained at the expense of only minimally increased grid obscuration. Because the design uses the grid fingers of the component cells as the interconnect structure, the area of the device used for this purpose becomes negligible. In this paper the authors report on the specifics of the design as well as issues related to the fabrication of the modules. Preliminary performance data for representative modules also are offered.

  8. Preparation and characterization of polystyrene-based monolith with ordered macroporous structure

    Institute of Scientific and Technical Information of China (English)

    Quan Zhou Wu; Jian Feng He; Ji Ming Ou

    2012-01-01

    In this paper,polystyrene-based monoliths with highly ordered macroporous structure were synthesized by using SiO2 colloidal crystal as template.SEM observation shows that the macropores are highly ordered and are interconnected by small windows.The BET surface area of PS monolith is about 36.17 m2/g.The polymer monoliths can resist 5 MPa pressure,showing high mechanical and compressive strength.

  9. Phased array of high-power, coherent, monolithic flared amplifier master oscillator power amplifiers

    Science.gov (United States)

    Osinski, J. S.; Mehuys, D.; Welch, D. F.; Waarts, R. G.; Major, J. S., Jr.; Dzurko, K. M.; Lang, R. J.

    1995-01-01

    A monolithically integrated array of InGaAs/AlGaAs flared amplifiers driven by a single DBR laser through a power splitter network and individually addressed phase modulators is described. Phase adjustment of ≳2π per element by free-carrier effects is verified by monitoring the interference pattern of all four emitters, and typically requires <15 mA of current to obtain a 2π phase shift. Phase matching is achieved among all four diffraction-limited emitters at a pulsed output power of ≳5 W, and, combined with the proper external lensing, could therefore result in an ultranarrow, single-lobed far-field pattern whose width is determined by the extended aperture of the array.

  10. Design of ultra-lightweight concrete: towards monolithic concrete structures

    Directory of Open Access Journals (Sweden)

    Yu Qing Liang

    2014-04-01

    Full Text Available This study addresses the development of ultra-lightweight concrete. A moderate strength and an excellent thermal conductivity of the lightweight concrete are set as the design targets. The designed lightweight aggregates concrete is targeted to be used in monolithic concrete façade structure, performing as both load bearing element and thermal insulator. The developed lightweight concrete shows excellent thermal properties, with a low thermal conductivity of about 0.12 W/(m·K; and moderate mechanical properties, with 28-day compressive strengths of about 10-12 N/mm . This combination of values exceeds, to the researchers’ knowledge, the performance of all other lightweight building materials. Furthermore, the developed lightweight concrete possesses excellent durability properties.

  11. An Energy Preserving Monolithic Eulerian Fluid-Structure Numerical Scheme

    CERN Document Server

    Pironneau, Olivier

    2016-01-01

    The conservation laws of continuum mechanic written in an Eulerian frame make no difference between fluids and solids except in the expression of the stress tensors, usually with Newton's hypothesis for the fluids and Helmholtz potentials of energy for hyperelastic solids. By taking the velocities as unknown , monolithic methods for fluid structure interactions (FSI) are built. In this article such a formulation is analyzed when the fluid is compressible and the fluid is incompressible. The idea is not new but the progress of mesh generators and numerical schemes like the Characteristics-Galerkin method render this approach feasible and reasonably robust. In this article the method and its discretization are presented, stability is discussed by through an energy estimate. A numerical section discusses implementation issues and presents a few simple tests.

  12. A Monolithic Perovskite Structure for Use as a Magnetic Regenerator

    DEFF Research Database (Denmark)

    Pryds, Nini; Clemens, Frank; Menon, Mohan

    2011-01-01

    A La0.67Ca0.26Sr0.07Mn1.05O3 (LCSM) perovskite was prepared for the first time as a ceramic monolithic regenerator used in a regenerative magnetic refrigeration device. The parameters influencing the extrusion process and the performance of the regenerator, such as the nature of the monolith paste...

  13. A symmetric positive definite formulation for monolithic fluid structure interaction

    KAUST Repository

    Robinson-Mosher, Avi

    2011-02-01

    In this paper we consider a strongly coupled (monolithic) fluid structure interaction framework for incompressible flow, as opposed to a loosely coupled (partitioned) method. This requires solving a single linear system that combines the unknown velocities of the structure with the unknown pressures of the fluid. In our previous work, we were able to obtain a symmetric formulation of this coupled system; however, it was also indefinite, making it more difficult to solve. In fact in practice there have been cases where we have been unable to invert the system. In this paper we take a novel approach that consists of factoring the damping matrix of deformable structures and show that this can be used to obtain a symmetric positive definite system, at least to the extent that the uncoupled systems were symmetric positive definite. We use a traditional MAC grid discretization of the fluid and a fully Lagrangian discretization of the structures for the sake of exposition, noting that our procedure can be generalized to other scenarios. For the special case of rigid bodies, where there are no internal damping forces, we exactly recover the system of Batty et al. (2007) [4]. © 2010 Elsevier Inc.

  14. Effect of absorbed pump power on the quality of output beam from monolithic microchip lasers

    Indian Academy of Sciences (India)

    Pranab K Mukhopadhyay; K Ranganathan; Jogy George; S K Sharma; T P S Nathan

    2002-04-01

    The dependence of the beam propagation factor (2 parameter) with the absorbed pump power in the case of monolithic microchip laser under face-cooled configuration is extensively studied. Our investigations show that the 2 parameter is related to the absorbed pump power through two parameters ( and ) whose values depend on the laser material properties and laser configuration. We have shown that one parameter arises due to the oscillation of higher order modes in the microchip cavity and the other parameter accounts for the spherical aberration associated with the thermal lens induced by the pump beam. Such dependency of 2 parameter with the absorbed pump power is experimentally verified for a face-cooled monolithic microchip laser based on Nd3+ - doped GdVO4 crystal and the values of and parameters were estimated from the experimentally measured data points.

  15. Monolithic Lumped Element Integrated Circuit (M2LEIC) Transistors.

    Science.gov (United States)

    INTEGRATED CIRCUITS, *MONOLITHIC STRUCTURES(ELECTRONICS), *TRANSISTORS, CHIPS(ELECTRONICS), FABRICATION, EPITAXIAL GROWTH, ULTRAHIGH FREQUENCY, POLYSILICONS, PHOTOLITHOGRAPHY, RADIOFREQUENCY POWER, IMPEDANCE MATCHING .

  16. Monolithic Microwave Integrated Circuits (MMIC) Broadband Power Amplifiers (Part 2)

    Science.gov (United States)

    2013-07-01

    2 Figure 2. A 2-GHz load-pull simulation of output power (Pcomp-6 x 65 µm PHEMT). ..............2 Figure 3. A 2-GHz load-pull simulation of PAE (6...5. MMIC 1–5 GHz output power and PAE performance simulation (1, 2, 3, and 4 GHz...load-pull simulation of PAE (6 x 50 µm PHEMT). .......................................7 Figure 9. MMIC 10–19 GHz broadband power amplifier linear

  17. Completely monolithic linearly polarized high-power fiber laser oscillator

    Science.gov (United States)

    Belke, Steffen; Becker, Frank; Neumann, Benjamin; Ruppik, Stefan; Hefter, Ulrich

    2014-03-01

    We have demonstrated a linearly polarized cw all-in-fiber oscillator providing 1 kW of output power and a polarization extinction ratio (PER) of up to 21.7 dB. The design of the laser oscillator is simple and consists of an Ytterbium-doped polarization maintaining large mode area (PLMA) fiber and suitable fiber Bragg gratings (FBG) in matching PLMA fibers. The oscillator has nearly diffraction-limited beam quality (M² high power 6+1:1 pump coupler. The slope efficiency of the laser is 75 %. The electro/optical efficiency of the complete laser system is ~30 % and hence in the range of Rofin's cw non-polarized fiber lasers. Choosing an adequate bending diameter for the Yb-doped PLMA fiber, one polarization mode as well as higher order modes are sufficiently supressed1. Resulting in a compact and robust linearly polarized high power single mode laser without external polarizing components. Linearly polarized lasers are well established for one dimensional cutting or welding applications. Using beam shaping optics radially polarized laser light can be generated to be independent from the angle of incident to the processing surface. Furthermore, high power linearly polarized laser light is fundamental for nonlinear frequency conversion of nonlinear materials.

  18. Monolithic Microwave Integrated Circuits (MMIC) Broadband Power Amplifiers

    Science.gov (United States)

    2012-12-01

    Pcomp-6x50 µm PHEMT). .............4 Figure 4. An 8-GHz load-pull simulation of PAE (6x50 µm PHEMT). ........................................4...layout. ..........................................................................9 Figure 12. MMIC 5–11 GHz output power and PAE performance...6x50 µm PHEMT). ...........11 Figure 16. A 4-GHz load-pull simulation of PAE (6x50 µm PHEMT). ......................................12 Figure 17

  19. A Ku-band high power density AlGaN/GaN HEMT monolithic power amplifier

    Institute of Scientific and Technical Information of China (English)

    Ge Qin; Chen Xiaojuan; Luo Weijun; Yuan Tingting; Pang Lei; Liu Xinyu

    2011-01-01

    A high power density monolithic power amplifier operated at Ku band is presented utilizing a 0.3 μm AlGaN/GaN HEMT production process on a 2-inch diameter semi-insulating (SI) 4H-SiC substrate by MOCVD.Over the 12-14 GHz frequency range,the single chip amplifier demonstrates a maximum power of 38 dBm (6.3 W),a peak power added efficiency (PAE) of 24.2% and linear gain of 6.4 to 7.5 dB under a 10% duty pulse conditionwhen operated at Vds =25 V and Vgs =-4 V.At these power levels,the amplifier exhibits a power density in excess of 5 W/mm.

  20. Monolithic solid oxide fuel cell technology advancement for coal-based power generation

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-14

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  1. A monolithic integrated low-voltage deep brain stimulator with wireless power and data transmission

    Science.gov (United States)

    Zhang, Zhang; Ye, Tan; Jianmin, Zeng; Xu, Han; Xin, Cheng; Guangjun, Xie

    2016-09-01

    A monolithic integrated low-voltage deep brain stimulator with wireless power and data transmission is presented. Data and power are transmitted to the stimulator by mutual inductance coupling, while the in-vitro controller encodes the stimulation parameters. The stimulator integrates the digital control module and can generate the bipolar current with equal amplitude in four channels. In order to reduce power consumption, a novel controlled threshold voltage cancellation rectifier is proposed in this paper to provide the supply voltage of the stimulator. The monolithic stimulator was fabricated in a SMIC 0.18 μm 1-poly 6-metal mixed-signal CMOS process, occupying 0.23 mm2, and consumes 180 μW on average. Compared with previously published stimulators, this design has advantages of large stimulated current (0-0.8 mA) with the double low-voltage supply (1.8 and 3.3 V), and high-level integration. Project supported by the National Natural Science Foundation of China (Nos. 61404043, 61401137), the Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences (Nos. IIMDKFJJ-13-06, IIMDKFJJ-14-03), and the Fundamental Research Funds for the Central Universities (No. 2015HGZX0026).

  2. A monolithic relativistic electron beam source based on a dielectric laser accelerator structure

    Energy Technology Data Exchange (ETDEWEB)

    McNeur, Josh; Carranza, Nestor; Travish, Gil; Yin Hairong; Yoder, Rodney [UCLA Dept. of Physics and Astronomy, Los Angeles, CA 90095 (United States); College of Physical Electronics, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610054 (China); Manhattanville College, Physics Dept., 2900 Purchase St., Purchase, NY 10577 (United States)

    2012-12-21

    Work towards a monolithic device capable of producing relativistic particle beams within a cubic-centimeter is detailed. We will discuss the Micro-Accelerator Platform (MAP), an optical laser powered dielectric accelerator as the main building block of this chip-scale source along with a field enhanced emitter and a region for sub-relativistic acceleration.

  3. Preparation of carbon monoliths having tailored pore structure from porous polymer precursors

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, R.R.

    1993-04-01

    This work concerns preparing tailored porous carbon monoliths by pyrolyzing porous polymer precursors. Prior work in this laboratory (1) demonstrated that a low density (0.05 g/cm{sup 3}), high void fraction (97 vol%) carbon monolith could be prepared by pyrolyzing a porous poly(acrylonitrile) (PAN) precursor. A higher density, more robust carbon material is preferred for certain applications, such as electrodes for electrochemical devices. The present work demonstrates that porous carbon monoliths having mass density of 0.7 g/cm{sup 3} can be prepared from a porous PAN precursor if the pyrolysis is controlled carefully. The macropore structure of the carbon is adjusted by changing the pore structure of the PAN precursor, and the finer scale structure (such as the crystallite size L{sub c}) is adjusted by varying the pyrolysis or heat treatment temperature.

  4. Preparation of carbon monoliths having tailored pore structure from porous polymer precursors

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, R.R.

    1993-01-01

    This work concerns preparing tailored porous carbon monoliths by pyrolyzing porous polymer precursors. Prior work in this laboratory (1) demonstrated that a low density (0.05 g/cm[sup 3]), high void fraction (97 vol%) carbon monolith could be prepared by pyrolyzing a porous poly(acrylonitrile) (PAN) precursor. A higher density, more robust carbon material is preferred for certain applications, such as electrodes for electrochemical devices. The present work demonstrates that porous carbon monoliths having mass density of 0.7 g/cm[sup 3] can be prepared from a porous PAN precursor if the pyrolysis is controlled carefully. The macropore structure of the carbon is adjusted by changing the pore structure of the PAN precursor, and the finer scale structure (such as the crystallite size L[sub c]) is adjusted by varying the pyrolysis or heat treatment temperature.

  5. Preparation and applications of monolithic structures containing metal-organic frameworks.

    Science.gov (United States)

    Lv, Yongqin; Tan, Xinyi; Svec, Frantisek

    2017-01-01

    Metal-organic frameworks are a new category of advanced porous materials with large surface areas and porosities, uniform pore sizes, tunable surface chemistry, and structural diversity. In combination with monoliths, they allow the fine tuning of desired interactions required in a variety of applications. This review article summarizes results of recent studies focused on synthetic strategies enabling incorporation of metal-organic frameworks in monolithic structures. A diverse array of applications including chromatographic separation, solid-phase microextraction, sample enrichment, heterogeneous catalysis, and enzymatic catalysis are also described. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Solvers for large-displacement fluid structure interaction problems: segregated versus monolithic approaches

    Science.gov (United States)

    Heil, Matthias; Hazel, Andrew L.; Boyle, Jonathan

    2008-12-01

    We compare the relative performance of monolithic and segregated (partitioned) solvers for large- displacement fluid structure interaction (FSI) problems within the framework of oomph-lib, the object-oriented multi-physics finite-element library, available as open-source software at http://www.oomph-lib.org . Monolithic solvers are widely acknowledged to be more robust than their segregated counterparts, but are believed to be too expensive for use in large-scale problems. We demonstrate that monolithic solvers are competitive even for problems in which the fluid solid coupling is weak and, hence, the segregated solvers converge within a moderate number of iterations. The efficient monolithic solution of large-scale FSI problems requires the development of preconditioners for the iterative solution of the linear systems that arise during the solution of the monolithically coupled fluid and solid equations by Newton’s method. We demonstrate that recent improvements to oomph-lib’s FSI preconditioner result in mesh-independent convergence rates under uniform and non-uniform (adaptive) mesh refinement, and explore its performance in a number of two- and three-dimensional test problems involving the interaction of finite-Reynolds-number flows with shell and beam structures, as well as finite-thickness solids.

  7. High pressure-resistant SU-8 microchannels for monolithic porous structure integration

    Science.gov (United States)

    Carlier, Julien; Chuda, Katarzyna; Arscott, Steve; Thomy, Vincent; Verbeke, Bernard; Coqueret, Xavier; Camart, Jean Christophe; Druon, Christian; Tabourier, Pierre

    2006-10-01

    Integrated lab-on-chip (LOC) microsystems dedicated to proteomic analysis require specific pretreatment steps such as protein trypsic digestion, concentration, desalting or separation of biological samples. These steps can be achieved thanks to porous monolithic polymers. This paper deals with the integration of such a polymer into SU-8 microchannels by using a multi-material technology (SU-8, Pyrex and silicon). A solution for the fabrication of complete polymer microchannels which are high pressure- and solvents-resistant is proposed. This technique uses the negative photoresist SU-8 which is compatible with the protein analysis performed here. Our process requires a novel technological step using a silane coupling agent. This modification of the SU-8/Pyrex interface leads to the fabrication of a 100 µm × 160 µm section microchannel (length of 3 cm), closed with a Pyrex® lid by SU-8 bonding resistant to 80 bar. An improvement of the SU-8/monolithic structure is also demonstrated thanks to a specific treatment of the polymer enabling good anchoring of the monolith in the microchannels, and the pressure-resistance tests were also achieved with the monolithic structure integrated in the microchannels. A digestion step of a protein sample of benzoylarginine ethyl ester in a SU-8 microchannel was achieved after the functionalization of a monolith anchored in the microchannel. Analysis by UV/VIS spectroscopy of this in situ digestion has been reported.

  8. The Importance of Pressure Sampling Frequency in Models for Determination of Critical Wave Loadings on Monolithic Structures

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Meinert, Palle

    2008-01-01

    Wave induced pressures on model scale monolithic structures like caissons and concrete superstructures on rubble mound breakwaters show very peaky variations, even in cases without impacts from slamming waves.......Wave induced pressures on model scale monolithic structures like caissons and concrete superstructures on rubble mound breakwaters show very peaky variations, even in cases without impacts from slamming waves....

  9. Proton Conduction in Sulfonated Organic-Inorganic Hybrid Monoliths with Hierarchical Pore Structure.

    Science.gov (United States)

    von der Lehr, Martin; Seidler, Christopher F; Taffa, Dereje H; Wark, Michael; Smarsly, Bernd M; Marschall, Roland

    2016-09-28

    Porous organic-inorganic hybrid monoliths with hierarchical porosity exhibiting macro- and mesopores are prepared via sol-gel process under variation of the mesopore size. Organic moieties in the pore walls are incorporated by substituting up to 10% of the silicon precursor tetramethylorthosilicate with bisilylated benzene molecules. After functionalization with sulfonic acid groups, the resulting sulfonated hybrid monoliths featuring a bimodal pore structure are investigated regarding proton conduction depending on temperature and relative humidity. The hierarchical pore system and controlled mesopore design turn out to be crucial for sulfonation and proton conduction. These sulfonated hybrid hierarchical monoliths containing only 10% organic precursor exhibit higher proton conduction at different relative humidities than sulfonated periodic mesoporous organosilica made of 100% bisilylated precursors exhibiting solely mesopores, even with a lower concentration of sulfonic acid groups.

  10. Monolithic ionizing particle detector based on active matrix of functionally integrated structures

    Energy Technology Data Exchange (ETDEWEB)

    Murashev, V.N. [National University of Science and Technology “MISIS” (Russian Federation); Legotin, S.A., E-mail: serlego@mail.ru [National University of Science and Technology “MISIS” (Russian Federation); Karmanov, D.E. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics (MSU SINP) (Russian Federation); Baryshnikov, F.M.; Didenko, S.I. [National University of Science and Technology “MISIS” (Russian Federation)

    2014-02-15

    Highlights: • A new type of monolithic silicon position detector is presented. • An operating principle, design and technology of the detector are described. • Calculated estimations of the detecting efficiency are carried out. • Experimental results of alpha-particle and electron detection are shown. -- Abstract: An operating principle, design and technology of a new type of the monolithic silicon position detector (MSPD) for registration of ionizing particles and photons are described. The detector represents a specialized monolithic silicon VLSI that contains a two-dimensional detecting matrix of active functionally integrated bipolar structures and peripheral electronic circuitry for signal amplification and processing. This paper presents experimental results of α-particles and electrons detection with position accuracy and operation speed better than 12.5 μm and 1 ns, respectively. The given estimations show the capabilities of this detector and its advantages in comparison with analogs.

  11. Structure and properties of hybrid poly(2-hydroxyethyl methacrylate)/SiO2 monoliths

    DEFF Research Database (Denmark)

    Ji, Xiangling; Jiang, Shichun; Qiu, Xuepeng

    2003-01-01

    to HEMA, was varied between 100/0 and 0/100. Structural analysis was performed by IR and NMR. The NMR results indicated that the introduction of PHEMA in the silica networks gave rise to a lower degree of condensation of TEOS. The resulting monoliths showed more than 75% transmittance in the visible...... related to some degree of chemical crosslinking between the polymer and the silica moiety, which would greatly improve the thermal stability of such hybrid monoliths compared with a pure PHEMA....

  12. Monolithic dual-band HgCdTe infrared detector structure

    CSIR Research Space (South Africa)

    Parish, G

    1997-07-01

    Full Text Available A monolithic HgCdTe photoconductive device structure is presented that is suitable for dual-band optically registered infrared photodetection in the two atmospheric transmission windows of 3-5 mu m and 8-12 mu m, which correspond to the mid...

  13. A High-Efficiency Monolithic DC-DC PFM Boost Converter with Parallel Power MOS Technique

    Directory of Open Access Journals (Sweden)

    Hou-Ming Chen

    2013-01-01

    Full Text Available This paper presents a high-efficiency monolithic dc-dc PFM boost converter designed with a standard TSMC 3.3/5V 0.35 μm CMOS technology. The proposed boost converter combines the parallel power MOS technique with pulse-frequency modulation (PFM technique to achieve high efficiency over a wide load current range, extending battery life and reducing the cost for the portable systems. The proposed parallel power MOS controller and load current detector exactly determine the size of power MOS to increase power conversion efficiency in different loads. Postlayout simulation results of the designed circuit show that the power conversion is 74.9–90.7% efficiency over a load range from 1 mA to 420 mA with 1.5 V supply. Moreover, the proposed boost converter has a smaller area and lower cost than those of the existing boost converter circuits.

  14. A bit-rate flexible and power efficient all-optical demultiplexer realised by monolithically integrated Michelson interferometer

    DEFF Research Database (Denmark)

    Vaa, Michael; Mikkelsen, Benny; Jepsen, Kim Stokholm;

    1996-01-01

    A novel bit-rate flexible and very power efficient all-optical demultiplexer using differential optical control of a monolithically integrated Michelson interferometer with MQW SOAs is demonstrated at 40 to 10 Gbit/s. Gain switched DFB lasers provide ultra stable data and control signals....

  15. Monoliths: A Review of the Basics, Preparation Methods and Their Relevance to Oxidation

    Directory of Open Access Journals (Sweden)

    Sandeeran Govender

    2017-02-01

    Full Text Available Considerable research has been conducted on monolithic catalysts for various applications. Strategies toward coating monoliths are of equal interest and importance. In this paper, the preparation of monoliths and monolithic catalysts have been summarized. More specifically, a brief explanation for the manufacturing of ceramic and metallic monoliths has been provided. Also, different methods for coating γ-alumina, as a secondary support, are included. Techniques used to deposit metal-based species, zeolites and carbon onto monoliths are discussed. Furthermore, monoliths extruded with metal oxides, zeolites and carbon are described. The main foci are on the reasoning and understanding behind the preparation of monolithic catalysts. Ideas and concerns are also contributed to encourage better approaches when designing these catalysts. More importantly, the relevance of monolithic structures to reactions, such as the selective oxidation of alkanes, catalytic combustion for power generation and the preferential oxidation of carbon monoxide, has been described.

  16. High-power coherent phased array of monolithic flared amplifier-master oscillator power amplifiers (MFA-MOPAs)

    Science.gov (United States)

    Osinski, Jules S.; Mehuys, David G.; Welch, David F.; Dzurko, Kenneth M.; Lang, Robert J.

    1995-04-01

    A monolithically integrated array of InGaAs/AlGaAs flared amplifiers driven by a single DBR laser through a power splitter network and individually addressed phase modulators is described. Phase adjustment of > 2(pi) per element by free-carrier effects is verified by monitoring the interference pattern of 4 emitters, and typically requires 5 W, and, combined with the proper external lensing, could therefore result in an ultra-narrow, single-lobed far-field pattern whose width is determined by the extended aperture of the array. This architecture is capable of providing single-mode, diffraction-limited performance from each emitter and is scalable to unprecedented power levels. Over 20 W of pulsed, spectrally coherent emission is generated at 955 nm from a 4-element array, and 39 W is obtained from an 8-element array.

  17. Encapsulated and monolithic resonant structures for laser applications

    Science.gov (United States)

    Pung, Aaron Joseph

    Typically, the composition of a laser system includes a gain medium, a pump illumination source, and an external feedback cavity. This cavity consists of a highly reflective mirror and an outcoupler component. The geometry of the outcoupler can be engineered to tailor the reflected or transmitted beam's spatial and spectral distribution. Functionally, the transmitted beam profile is dependent on the laser application. Broadband reflection profiles can be obtained by utilizing a distributed Bragg reflector (DBR). A DBR device consists of multiple layers of alternating materials. Constructive interference of the reflected light off each interface between different materials produces the spectrally broadband response. The spectral response is a function of the fabrication and material parameters of the DBR. In contrast, guided-mode resonance filters (GMRF) exploit phase matching between evanescent- and guided-waves to provide a strong reflection. Based on the materials in the structure, the spectral response can demonstrate broadband or narrowband reflectivity. The operation wavelength of a GMRF is dependent on the structural parameters of the device as well as the angle of incidence. However, conventional designs of resonant optics leave critical aspects of the structure exposed to the surrounding environment. Additional damage or contamination to the waveguide or grating layer will significantly alter the device's spectral response. This dissertation introduces two GMRF geometries aimed at device integration, development of similar-material resonant devices, and full-device protection from outside influence. Unlike distributed Bragg reflectors, these geometries do not rely heavily on strict material and deposition requirements. Instead, they take advantage of the deposition processes to minimize coating deposition, achieve high reflectivity and demonstrate control over polarization dependence. Given their versatility in design and ability to withstand high power

  18. Monolithic Silicon Photodetector - Detector of Ionizing Radiation Based on Functional Integrated MOS Structures

    Directory of Open Access Journals (Sweden)

    S.A. Legotin

    2014-07-01

    Full Text Available This paper describes the principle of operation, construction, architecture and fabrication of a new type of monolithic silicon coordinate photodetector - detector of optical and ionizing radiation (MSCP on the basis of functional integrated MOS structures. The analytical estimation of electrophysical characteristics MSCP is given. It is shown that MSCP is a specialized monolithic silicon VLSI containing two-dimensional pixel array with high and low voltage functionally integrated structures (FIS and peripheral electronic circuits of amplification and signal processing matrix. Estimations and presents comparative characteristics are presented. They show potential MSCP possibilities for registration of optical and ionizing radiation. Experimental results of α-particles and electrons registration. The possible areas of application, with the possibility of its use in a wide X-ray panels medical supplies, X-rays, etc are considered.

  19. Self-Powered Ultrabroadband Photodetector Monolithically Integrated on a PMN-PT Ferroelectric Single Crystal.

    Science.gov (United States)

    Fang, Huajing; Xu, Chao; Ding, Jie; Li, Qiang; Sun, Jia-Lin; Dai, Ji-Yan; Ren, Tian-Ling; Yan, Qingfeng

    2016-12-07

    Photodetectors capable of detecting two or more bands simultaneously with a single system have attracted extensive attentions because of their critical applications in image sensing, communication, and so on. Here, we demonstrate a self-powered ultrabroadband photodetector monolithically integrated on a 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (PMN-28PT) single crystal. By combining the optothermal and pyroelectric effect, the multifunctional PMN-28PT single crystal can response to a wide wavelength range from UV to terahertz (THz). At room temperature, the photodetector could generate a pyroelectric current under the intermittent illumination of incident light in absence of external bias. A systematic study of the photoresponse was investigated. The pyroelectric current shows an almost linear relationship to illumination intensity. Benefiting from the excellent pyroelectric property of PMN-28PT single crystal and the optimized device architecture, the device exhibited a dramatic improvement in operation frequency up to 3 kHz without any obvious degradation in sensitivity. Such a self-powered photodetector with ultrabroadband response may open a window for the novel application of ferroelectric materials in optoelectronics.

  20. Holographic Structuring of Elastomer Actuator: First True Monolithic Tunable Elastomer Optics.

    Science.gov (United States)

    Ryabchun, Alexander; Kollosche, Matthias; Wegener, Michael; Sakhno, Oksana

    2016-12-01

    Volume diffraction gratings (VDGs) are inscribed selectively by diffusive introduction of benzophenone and subsequent UV-holographic structuring into an electroactive dielectric elastomer actuator (DEA), to afford a continuous voltage-controlled grating shift of 17%. The internal stress coupling of DEA and optical domain allows for a new generation of true monolithic tunable elastomer optics with voltage controlled properties. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Tunable mechanical monolithic sensors for large band low frequency monitoring and characterization of sites and structures

    Science.gov (United States)

    Barone, F.; Giordano, G.; Acernese, F.; Romano, R.

    2016-10-01

    Among the different mechanical architectures present in literature, the Watts linkage is one of the most promising ones for the implementation of a new class of mechanical accelerometers (horizontal, vertical and angular). In this paper, we present monolithic implementations of uniaxial and triaxial mechanical seismometers and accelerometers based on the UNISA Folded Pendulum mechanical configuration, optimized for low frequency characterization of sites (including underground sites) and structures as inertial sensor (seismometer). This mechanical architecture allows the design and implementation of very large band monolithic sensors (10-7Hz 102 Hz), whose sensitivities for the most common applications are defined by the noise introduced by their readouts (e.g. ¡ 10-12 m/sqrt(Hz) with classical LVDT readouts). These unique features, coupled other relevant properties like scalability, compactness, lightness, high directivity, frequency tunability (typical resonance frequencies in the band 10-1 Hz 102 Hz), very high immunity to environmental noises and low cost make this class of sensors very effective for the implementation of uniaxial (horizontal and/or vertical) and triaxial seismometers and accelerometers for ground, space and underwater applications, including UHV and cryogenics ones. Typical applications of this class of monolithic sensors are in the field of earthquake engineering, seismology, geophysics, civil engineering, characterization of sites (including underground sites), structures (e.g. buildings, bridges, historical monuments), and, in general, in all applications requiring large band-low frequency performances coupled with high sensitivities and compactness.

  2. High-power coherent GaAs-based monolithic semiconductor lasers

    Science.gov (United States)

    Botez, Dan

    2001-11-01

    Stable-beam operation to high coherent powers from large aperture devices can only be obtained from active-photonic- lattice (APL) structures of large built-in index step. Resonant phase-locked arrays of antiguides, so called ROW array, have provided 1.6W CW coherent power from 200micrometers - wide apertures. Two-dimensional surface-emitting APLs combining ROW arrays and DFB-DBR structures with central (pi) phase-shift are capable of providing coherent powers in the multi-watt range. ARROW-type devices, simpler APL structures, hold the potential for emitting 1W single-mode CW power reliability in stable beam patterns.

  3. The Importance of Pressure Sampling Frequency in Models for Determination of Critical Wave Loadingson Monolithic Structures

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Meinert, Palle

    2008-01-01

    This paper discusses the influence of wave load sampling frequency on calculated sliding distance in an overall stability analysis of a monolithic caisson. It is demonstrated by a specific example of caisson design that for this kind of analyses the sampling frequency in a small scale model could...... be as low as 100 Hz in model scale. However, for design of structure elements like the wave wall on the top of a caisson the wave load sampling frequency must be much higher, in the order of 1000 Hz in the model. Elastic-plastic deformations of foundation and structure were not included in the analysis....

  4. Widely Tunable Monolithic Mid-Infrared Quantum Cascade Lasers Using Super-Structure Grating Reflectors

    OpenAIRE

    Dingkai Guo; Jiun-Yun Li; Liwei Cheng; Xing Chen; Terry Worchesky; Fow-Sen Choa

    2016-01-01

    A monolithic, three-section, and widely tunable mid-infrared (mid-IR) quantum cascade laser (QCL) is demonstrated. This electrically tuned laser consists of a gain section placed between two super structure grating (SSG) distributed Bragg reflectors (DBRs). By varying the injection currents to the two grating sections of this device, its emission wavelength can be tuned from 4.58 μm to 4.77 μm (90 cm−1) with a supermode spacing of 30 nm. This type of SSG-DBR QCLs can be a compact replacement ...

  5. Structural power flow measurement

    Energy Technology Data Exchange (ETDEWEB)

    Falter, K.J.; Keltie, R.F.

    1988-12-01

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  6. Design of monoliths through their mechanical properties.

    Science.gov (United States)

    Podgornik, Aleš; Savnik, Aleš; Jančar, Janez; Krajnc, Nika Lendero

    2014-03-14

    Chromatographic monoliths have several interesting properties making them attractive supports for analytics but also for purification, especially of large biomolecules and bioassemblies. Although many of monolith features were thoroughly investigated, there is no data available to predict how monolith mechanical properties affect its chromatographic performance. In this work, we investigated the effect of porosity, pore size and chemical modification on methacrylate monolith compression modulus. While a linear correlation between pore size and compression modulus was found, the effect of porosity was highly exponential. Through these correlations it was concluded that chemical modification affects monolith porosity without changing the monolith skeleton integrity. Mathematical model to describe the change of monolith permeability as a function of monolith compression modulus was derived and successfully validated for monoliths of different geometries and pore sizes. It enables the prediction of pressure drop increase due to monolith compressibility for any monolith structural characteristics, such as geometry, porosity, pore size or mobile phase properties like viscosity or flow rate, based solely on the data of compression modulus and structural data of non-compressed monolith. Furthermore, it enables simple determination of monolith pore size at which monolith compressibility is the smallest and the most robust performance is expected. Data of monolith compression modulus in combination with developed mathematical model can therefore be used for the prediction of monolith permeability during its implementation but also to accelerate the design of novel chromatographic monoliths with desired hydrodynamic properties for particular application.

  7. High-Power and Low-Noise 10-GHz All-Active Monolithic Mode-Locked Lasers with Surface Etched Bragg Grating

    DEFF Research Database (Denmark)

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter.......We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter....

  8. Optimal design of a spectral readout type planar waveguide-mode sensor with a monolithic structure.

    Science.gov (United States)

    Wang, Xiaomin; Fujimaki, Makoto; Kato, Takafumi; Nomura, Ken-Ichi; Awazu, Koichi; Ohki, Yoshimichi

    2011-10-10

    Optical planar waveguide-mode sensor is a promising candidate for highly sensitive biosensing techniques in fields such as protein adsorption, receptor-ligand interaction and surface bacteria adhesion. To make the waveguide-mode sensor system more realistic, a spectral readout type waveguide sensor is proposed to take advantage of its high speed, compactness and low cost. Based on our previously proposed monolithic waveguide-mode sensor composed of a SiO2 waveguide layer and a single crystalline Si layer [1], the mechanism for achieving high sensitivity is revealed by numerical simulations. The optimal achievable sensitivities for a series of waveguide structures are summarized in a contour map, and they are found to be better than those of previously reported angle-scan type waveguide sensors.

  9. Widely Tunable Monolithic Mid-Infrared Quantum Cascade Lasers Using Super-Structure Grating Reflectors

    Directory of Open Access Journals (Sweden)

    Dingkai Guo

    2016-05-01

    Full Text Available A monolithic, three-section, and widely tunable mid-infrared (mid-IR quantum cascade laser (QCL is demonstrated. This electrically tuned laser consists of a gain section placed between two super structure grating (SSG distributed Bragg reflectors (DBRs. By varying the injection currents to the two grating sections of this device, its emission wavelength can be tuned from 4.58 μm to 4.77 μm (90 cm−1 with a supermode spacing of 30 nm. This type of SSG-DBR QCLs can be a compact replacement for the external cavity QCL. It has great potential to achieve gap-free and even further tuning ranges for sensor applications.

  10. High-power monolithic single-mode diode lasers employing active photonic lattices

    Science.gov (United States)

    Botez, Dan

    2003-06-01

    Photonic-lattice structures with modulated gain, that is active photonic lattices (APLs), of large index steps and gain preferentially enhanced on the low-index lattice sites have been used, as early as 1988, for effective lateral-mode control range in large-aperture (100-200 microns) high-power coherent devices. Photonic-bandpass (PBP) structures relying on long-range resonant leaky-wave coupling, so called ROW arrays, have allowed stable, near-diffraction-limited beam operation to powers as high as 1.6W CW and 10W peak pulsed. Photonic-bandgap (PBG) structures with a built-in lattice defect, so called ARROW lasers, have provided up to 0.5W peak-pulsed stable, single-mode power and hold the potential for 1W CW reliable single-mode operation from apertures 8-10 microns wide. The solution for high-efficiency surface emission, from 2nd-order DFB/DBR lasers, in an orthonormal, single-lobe beam pattern was found in 2000. Recently, single-lobe and single-mode operation in a diffraction-limited beam orthonormal to the chip surface was demonstrated from 1.5mm-long DFB/DBR ridge-guide lasers. That opens the way for the realization of 2-D surface-emitting,2nd-order APLs for the stable generation of watts of CW single-lobe, single-mode power from large 2-D apertures, as well as scalability of such devices at the wafer level.

  11. High-Power and Low-Noise 10-GHz All-Active Monolithic Mode-Locked Lasers with Surface Etched Bragg Grating

    OpenAIRE

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter.

  12. A Sampled Grating DBR Laser Monolithically Integrated by Using SOAs with 22 mW Output Power and 51 ITU 100 GHz Channels over 43 nm

    Science.gov (United States)

    Liu, Yang; Ye, Nan; Zhou, Dai-Bing; Wang, Bao-Jun; Pan, Jiao-Qing; Zhao, Ling-Juan; Wang, Wei

    2011-02-01

    A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43 nm from 1514.05 nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 mW for all output wavelengths, is successfully demonstrated.

  13. Evolution of Monolithic Technology for Wireless Communications: GaN MMIC Power Amplifiers For Microwave Radios

    Directory of Open Access Journals (Sweden)

    Vittorio Camarchia

    2014-09-01

    Full Text Available This paper presents the progress of monolithic technology for microwaveapplication, focusing on gallium nitride technology advances in the realization of integratedpower amplifiers. Three design examples, developed for microwave backhaul radios, areshown. The first design is a 7 GHz Doherty developed with a research foundry, while thesecond and the third are a 7 GHz Doherty and a 7–15 GHz dual-band combined poweramplifiers, both based on a commercial foundry process. The employed architectures, themain design steps and the pros and cons of using gallium nitride technology are highlighted.The measured performance demonstrates the potentialities of the employed technology, andthe progress in the accuracy, reliability and performance of the process.

  14. Monolithic-Structured Single-Layered Textile-Based Dye-Sensitized Solar Cells

    Science.gov (United States)

    Yun, Min Ju; Cha, Seung I.; Kim, Han Seong; Seo, Seon Hee; Lee, Dong Y.

    2016-10-01

    Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells—including the preparation of fibre-type solar cells woven into textiles—face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes’ surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research.

  15. Monolithic-Structured Single-Layered Textile-Based Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Yun, Min Ju; Cha, Seung I; Kim, Han Seong; Seo, Seon Hee; Lee, Dong Y

    2016-10-06

    Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells-including the preparation of fibre-type solar cells woven into textiles-face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes' surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research.

  16. Monolithic solid oxide fuel cell technology advancement for coal-based power generation

    Science.gov (United States)

    1994-05-01

    This project has successfully advanced the technology for MSOFC's for coal-based power generation. Major advances include: tape-calendering processing technology, leading to 3X improved performance at 1000 C; stack materials formulations and designs with sufficiently close thermal expansion match for no stack damage after repeated thermal cycling in air; electrically conducting bonding with excellent structural robustness; and sealants that form good mechanical seals for forming manifold structures. A stack testing facility was built for high-spower MSOFC stacks. Comprehensive models were developed for fuel cell performance and for analyzing structural stresses in multicell stacks and electrical resistance of various stack configurations. Mechanical and chemical compatibility properties of fuel cell components were measured; they show that the baseline Ca-, Co-doped interconnect expands and weakens in hydrogen fuel. This and the failure to develop adequate sealants were the reason for performance shortfalls in large stacks. Small (1-in. footprint) two-cell stacks were fabricated which achieved good performance (average area-specific-resistance 1.0 ohm-sq cm per cell); however, larger stacks had stress-induced structural defects causing poor performance.

  17. Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

    Energy Technology Data Exchange (ETDEWEB)

    Yang, P., E-mail: yangping0710@126.com [Central China Normal University, Wuhan (China); Aglieri, G.; Cavicchioli, C. [CERN, 1210 Geneva 23 (Switzerland); Chalmet, P.L. [MIND, Archamps (France); Chanlek, N. [Suranaree University of Technology, Nakhon Ratchasima (Thailand); Collu, A. [University of Cagliari, Cagliari (Italy); INFN (Italy); Gao, C. [Central China Normal University, Wuhan (China); Hillemanns, H.; Junique, A. [CERN, 1210 Geneva 23 (Switzerland); Kofarago, M. [CERN, 1210 Geneva 23 (Switzerland); University of Utrecht, Utrecht (Netherlands); Keil, M.; Kugathasan, T. [CERN, 1210 Geneva 23 (Switzerland); Kim, D. [Dongguk and Yonsei University, Seoul (Korea, Republic of); Kim, J. [Pusan National University, Busan (Korea, Republic of); Lattuca, A. [University of Torino, Torino (Italy); INFN (Italy); Marin Tobon, C.A. [CERN, 1210 Geneva 23 (Switzerland); Marras, D. [University of Cagliari, Cagliari (Italy); INFN (Italy); Mager, M.; Martinengo, P. [CERN, 1210 Geneva 23 (Switzerland); Mazza, G. [University of Torino, Torino (Italy); INFN (Italy); and others

    2015-06-11

    Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented.

  18. Fabrication of Monolithic Bridge Structures by Vacuum-Assisted Capillary-Force Lithography

    KAUST Repository

    Kwak, Rhokyun

    2009-04-06

    Monolithic bridge structures were fabricated by using capillary-force lithography (CFL), which was developed for patterning polymers over a large area by combining essential features of nanoimprint lithography and capillarity. A patterned soft mold was placed on a spin-coated UV-curable resin on a substrate. The polymer then moved into the cavity of the mold by capillary action and then solidified after exposure to UV radiation. The uncured resin was forced to migrate into the cavity of a micropatterned PDMS mold by capillarity, and then exposed to UV radiation under a high-energy mercury lamp with intensity. A rotary pump was then turned on, decreasing the air pressure in the chamber. SEM images were taken with a high-resolution SEM at an acceleration voltage greater than 15 kV. It was observed that when the air pressure was rapidly reduced to a low vacuum, the top layer moved into the nanochannels with a meniscus at the interface between the nanoscale PUA and the base structure.

  19. PREPARATION OF POROUS NANOCOMPOSITE SCAFFOLDS WITH HONEYCOMB MONOLITH STRUCTURE BY ONE PHASE SOLUTION FREEZE DRYING METHOD

    Institute of Scientific and Technical Information of China (English)

    Yang Xu; Duo Zhang; Zong-liang Wang; Zhan-tuan Gao; Pei-biao Zhang; Xue-si Chen

    2011-01-01

    Biodegradable porous nanocomposite scaffolds of poly(lactide-co-glycolide) (PLGA) and L-lactic acid (LAc) oligomer surface-grafted hydroxyapatite nanoparticles (op-HA) with a honeycomb monolith structure were fabricated with the single-phase solution freeze-drying method. The effects of different freezing temperatures on the properties of the scaffolds, such as microstructures, compressive strength, cell penetration and cell proliferation were studied. The highly porous and well interconnected scaffolds with a tunable pore structure were obtained. The effect of different freezing temperature (4℃, -20℃, -80℃ and -196℃) was investigated in relation to the scaffold morphology, the porosity varied from 91.2% to 83.0% and the average pore diameter varied from (167.2 ± 62.6) pm to (11.9 ± 4.2) μm while the σ10 increased significantly. The cell proliferation were decreased and associated with the above-mentioned properties. Uniform distribution of op-HA particles and homogeneous roughness of pore wall surfaces were found in the 4℃ frozen scaffold. The 4℃ frozen scaffold exhibited better cell penetration and increased cell proliferation because of its larger pore size, higher porosity and interconnection. The microstmctures described here provide a new approach for the design and fabrication of op-HA/PLGA based scaffold materials with potentially broad applicability for replacement of bone defects.

  20. Structure and properties of hybrid poly(2-hydroxyethyl methacrylate)/SiO2 monoliths

    DEFF Research Database (Denmark)

    Ji, Xiangling; Jiang, Shichun; Qiu, Xuepeng

    2003-01-01

    Abstract: Hybrid poly(2-hydroxyethyl methacrylate) (PHEMA)/SiO2 monoliths were synthesized via a sol-gel process of the precursor tetraethyl orthosilicate (TEOS) and the in situ free-radical polymerization of 2-hydroxyethyl methacrylate (HEMA). The weight ratio of the starting chemicals, TEOS to ...... related to some degree of chemical crosslinking between the polymer and the silica moiety, which would greatly improve the thermal stability of such hybrid monoliths compared with a pure PHEMA....

  1. Bioaffinity chromatography on monolithic supports

    NARCIS (Netherlands)

    Tetala, K.K.R.; Beek, van T.A.

    2010-01-01

    Affinity chromatography on monolithic supports is a powerful analytical chemical platform because it allows for fast analyses, small sample volumes, strong enrichment of trace biomarkers and applications in microchips. In this review, the recent research using monolithic materials in the field of bi

  2. Bioaffinity chromatography on monolithic supports

    NARCIS (Netherlands)

    Tetala, K.K.R.; Beek, van T.A.

    2010-01-01

    Affinity chromatography on monolithic supports is a powerful analytical chemical platform because it allows for fast analyses, small sample volumes, strong enrichment of trace biomarkers and applications in microchips. In this review, the recent research using monolithic materials in the field of bi

  3. Monolithic Y-Ba-Cu-O structures fabricated using the laser-writing patterning technique

    Energy Technology Data Exchange (ETDEWEB)

    Sobolewski, R.; Xiong, W.; Kula, W.; Maung, W.N.; Butler, D.P. [Dept. of Electr. Eng., Rochester Univ., NY (United States)

    1994-05-01

    We report our progress in fabrication of thin-film YBa{sub 2}Cu{sub 3}O{sub x} (YBCO) superconducting electronic devices, using a recently developed, laser-writing patterning technique. Laser writing allows one to form in the same YBCO film planar patterns that consist of both the oxygen-rich (superconducting) and the oxygen-poor (semiconducting) phases. The patterns are highly uniform with very sharp (less than 1 mu m wide) superconductor-semiconductor interfaces. The oxygen-rich regions possess excellent superconducting properties with critical temperatures as high as those of the best epitaxial films, and critical current densities above 2x10{sup 6} A cm{sup -2} at 77 K. Simultaneously, the oxygen-poor regions exhibit a disordered-semiconductor-like, thermally activated transport. Below 100 K, they are almost insulating and characterized by relatively low (below 20) dielectric constant and low microwave loss. A number of test structures, consisting of oxygen-rich and oxygen-poor microbridges and coplanar microwave transmission lines and resonators, was fabricated and tested. All these devices are completely monolithic and were used to study DC and microwave transport properties of the oxygen-rich and oxygen-poor YBCO phases. (author)

  4. Parallel BDD-based monolithic approach for acoustic fluid-structure interaction

    Science.gov (United States)

    Minami, Satsuki; Kawai, Hiroshi; Yoshimura, Shinobu

    2012-12-01

    Parallel BDD-based monolithic algorithms for acoustic fluid-structure interaction problems are developed. In a previous study, two schemes, NN-I + CGC-FULL and NN-I + CGC-DIAG, have been proven to be efficient among several BDD-type schemes for one processor. Thus, the parallelization of these schemes is discussed in the present study. These BDD-type schemes consist of the operations of the Schur complement matrix-vector (Sv) product, Neumann-Neumann (NN) preconditioning, and the coarse problem. In the present study, the Sv product and NN preconditioning are parallelized for both schemes, and the parallel implementation of the solid and fluid parts of the coarse problem is considered for NN-I + CGC-DIAG. The results of numerical experiments indicate that both schemes exhibit performances that are almost as good as those of single solid and fluid analyses in the Sv product and NN preconditioning. Moreover, NN-I + CGC-DIAG appears to become more efficient as the problem size becomes large due to the parallel calculation of the coarse problem.

  5. Power as a structural phenomenon.

    Science.gov (United States)

    Neal, Jennifer Watling; Neal, Zachary P

    2011-12-01

    In an effort to inform empowerment theory and research, this paper provides a structural conception of power. First, we examine the essential features present in three dominant conceptions of power in community psychology: social power, psychopolitical power, and relational power. Next, commonalities in the key features of power identified by these conceptions are explored and pared down to yield a more parsimonious conception of power that is grounded only in the structural pattern of relationships through which resources are exchanged. Drawing on social exchange theory, we offer a method for measuring this streamlined, structural conception of power that allows for its more precise examination. Finally, we discuss the implications of a structural conception and measurement of power for targeting and facilitating empowering processes and evaluating empowered outcomes.

  6. Back End of Line Nanorelays for Ultra-low Power Monolithic Integrated NEMS-CMOS Circuits

    KAUST Repository

    Lechuga Aranda, Jesus Javier

    2016-05-01

    Since the introduction of Complementary-Metal-Oxide-Semiconductor (CMOS) technology, the chip industry has enjoyed many benefits of transistor feature size scaling, including higher speed and device density and improved energy efficiency. However, in the recent years, the IC designers have encountered a few roadblocks, namely reaching the physical limits of scaling and also increased device leakage which has resulted in a slow-down of supply voltage and power density scaling. Therefore, there has been an extensive hunt for alternative circuit architectures and switching devices that can alleviate or eliminate the current crisis in the semiconductor industry. The Nano-Electro-Mechanical (NEM) relay is a promising alternative switch that offers zero leakage and abrupt turn-on behaviour. Even though these devices are intrinsically slower than CMOS transistors, new circuit design techniques tailored for the electromechanical properties of such devices can be leveraged to design medium performance, ultra-low power integrated circuits. In this thesis, we deal with a new generation of such devices that is built in the back end of line (BEOL) CMOS process and is an ideal option for full integration with current CMOS transistor technology. Simulation and verification at the circuit and system level is a critical step in the design flow of microelectronic circuits, and this is especially important for new technologies that lack the standard design infrastructure and well-known verification platforms. Although most of the physical and electrical properties of NEM structures can be simulated using standard electronic automation software, there is no report of a reliable behavioural model for NEMS switches that enable large circuit simulations. In this work, we present an optimised model of a BEOL nano relay that encompasses all the electromechanical characteristics of the device and is robust and lightweight enough for VLSI applications that require simulation of thousands of

  7. Quasi-Monolithic Structures for Spaceflight Using Hydroxide-Catalysis Bonding

    Science.gov (United States)

    Preston, Alix; Thorpe, J. Ira; Miner, Linda

    2012-01-01

    Future space-based missions will take measurements of the universe with unprecedented results. To do this, these missions will require materials and bonding techniques with ever-increasing stability in order to make their measurements. As an example, the Laser Interferometer Space Antenna (LISA) will detect and observe gravitational waves in the 0.1 mHz to 1 Hz frequency range with strain sensitivities on the order of 10(exp -21) at its most sensitive frequency. To make these measurements, critical components such as the optical bench or telescope support structure, will need to have path-length stabilities of better than 1 pm/(square root)Hz. The baseline construction method for the LISA optical bench is to affix fused silica optical components to a Zerodur baseplate using hydroxide-catalysis bonding (HCB). HCB is a recently developed technique that allows the bonding of glasses, some metals, and silicon carbide with significant strength and stability with a bond thickness of less than a few micrometers. In addition, a wide range of surface profiles can be bonded using only a small amount of hydroxide solution. These characteristics make HCB ideal for adhering optical components in complex optical systems. In addition to being used to construct the LISA optical bench, the HCB technique shows great promise for constructing other structures such as hollow retroreflectors to be used for lunar laser ranging, or a visible nulling coronograph to be used for exo-planet detection. Here we present construction techniques that could be used to make an optical bench, hollow retroreflector, nulling coronograph, or other quasi-monolithic structures using HCB. In addition, we present dimensional stability results of an optical bench that was made using HCB, as well as HCB strength measurements.

  8. A preliminary investigation of the growth of an aneurysm with a multiscale monolithic Fluid-Structure interaction solver

    Science.gov (United States)

    Cerroni, D.; Manservisi, S.; Pozzetti, G.

    2015-11-01

    In this work we investigate the potentialities of multi-scale engineering techniques to approach complex problems related to biomedical and biological fields. In particular we study the interaction between blood and blood vessel focusing on the presence of an aneurysm. The study of each component of the cardiovascular system is very difficult due to the fact that the movement of the fluid and solid is determined by the rest of system through dynamical boundary conditions. The use of multi-scale techniques allows us to investigate the effect of the whole loop on the aneurysm dynamic. A three-dimensional fluid-structure interaction model for the aneurysm is developed and coupled to a mono-dimensional one for the remaining part of the cardiovascular system, where a point zero-dimensional model for the heart is provided. In this manner it is possible to achieve rigorous and quantitative investigations of the cardiovascular disease without loosing the system dynamic. In order to study this biomedical problem we use a monolithic fluid-structure interaction (FSI) model where the fluid and solid equations are solved together. The use of a monolithic solver allows us to handle the convergence issues caused by large deformations. By using this monolithic approach different solid and fluid regions are treated as a single continuum and the interface conditions are automatically taken into account. In this way the iterative process characteristic of the commonly used segregated approach, it is not needed any more.

  9. Simulation Based Optimization of Complex Monolithic Composite Structures Using Cellular Core Technology

    Science.gov (United States)

    Hickmott, Curtis W.

    Cellular core tooling is a new technology which has the capability to manufacture complex integrated monolithic composite structures. This novel tooling method utilizes thermoplastic cellular cores as inner tooling. The semi-rigid nature of the cellular cores makes them convenient for lay-up, and under autoclave temperature and pressure they soften and expand providing uniform compaction on all surfaces including internal features such as ribs and spar tubes. This process has the capability of developing fully optimized aerospace structures by reducing or eliminating assembly using fasteners or bonded joints. The technology is studied in the context of evaluating its capabilities, advantages, and limitations in developing high quality structures. The complex nature of these parts has led to development of a model using the Finite Element Analysis (FEA) software Abaqus and the plug-in COMPRO Common Component Architecture (CCA) provided by Convergent Manufacturing Technologies. This model utilizes a "virtual autoclave" technique to simulate temperature profiles, resin flow paths, and ultimately deformation from residual stress. A model has been developed simulating the temperature profile during curing of composite parts made with the cellular core technology. While modeling of composites has been performed in the past, this project will look to take this existing knowledge and apply it to this new manufacturing method capable of building more complex parts and develop a model designed specifically for building large, complex components with a high degree of accuracy. The model development has been carried out in conjunction with experimental validation. A double box beam structure was chosen for analysis to determine the effects of the technology on internal ribs and joints. Double box beams were manufactured and sectioned into T-joints for characterization. Mechanical behavior of T-joints was performed using the T-joint pull-off test and compared to traditional

  10. A Sampled Grating DBR Laser Monolithically Integrated by Using SOAs with 22mW Output Power and 51 ITU 100 GHz Channels over 43 nm

    Institute of Scientific and Technical Information of China (English)

    LIU Yang; YE Nan; ZHOU Dai-Bing; WANG Bao-Jun; PAN Jiao-Qing; ZHAO Ling-Juan; WANG Wei

    2011-01-01

    @@ A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43nm from 1514.05 nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 mW for all output wavelengths, is successfully demonstrated.%A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43nm from 1514.05nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 m W for all output wavelengths,is successfully demonstrated.

  11. Monolithic spectrometer

    Science.gov (United States)

    Rajic, Slobodan; Egert, Charles M.; Kahl, William K.; Snyder, Jr., William B.; Evans, III, Boyd M.; Marlar, Troy A.; Cunningham, Joseph P.

    1998-01-01

    A monolithic spectrometer is disclosed for use in spectroscopy. The spectrometer is a single body of translucent material with positioned surfaces for the transmission, reflection and spectral analysis of light rays.

  12. Modeling and design of a monolithically integrated power converter on SiC

    Science.gov (United States)

    Yu, L. C.; Sheng, K.; Zhao, J. H.

    2008-10-01

    To fully explore the high temperature and high power density potential of the 4H-SiC material, not only power devices need to be fabricated on SiC, but also the circuitries for signal generation/processing, gate driver and control. In this paper, static and dynamic characteristics of SiC lateral JFET (LJFET) devices are numerically simulated and compact circuit models developed. Based on these models, analog and digital integrated circuits functional blocks such as OPAMP, gate driver and logic gates are then designed and simulated. Finally, a fully integrated power converter including pulse-width-modulation circuit, over-temperature protection circuit and a power boost converter is designed and simulated. The converter has an input of 200 V and an output voltage of 400 V, 2.5 A, operating at 1 kW and 5 MHz.

  13. Hierarchically porous Ni monolith@branch-structured NiCo2O4 for high energy density supercapacitors

    Institute of Scientific and Technical Information of China (English)

    Mengjie Xu; Rongjun Xu; Ying Zhao; Libao Chen; Boyun Huang; Weifeng Wei n

    2016-01-01

    A variety of NiCo2O4 nanostrucutures ranging from nanowire to nanoplate and branched structures were successfully prepared via a simple hydrothermal process. The experimental results show that NiCo2O4 with branched structures possesses the best overall electrochemical performance. The improvement of energy density was explored in terms of hierarchically three-dimensional (3D) metal substrates and a high specific area capacitance, and area energy density is obtained with hierarchically porous Ni monolith synthesized through a controlled combustion procedure.

  14. Hierarchically porous Ni monolith@branch-structured NiCo2O4 for high energy density supercapacitors

    Directory of Open Access Journals (Sweden)

    Mengjie Xu

    2016-06-01

    Full Text Available A variety of NiCo2O4 nanostrucutures ranging from nanowire to nanoplate and branched structures were successfully prepared via a simple hydrothermal process. The experimental results show that NiCo2O4 with branched structures possesses the best overall electrochemical performance. The improvement of energy density was explored in terms of hierarchically three-dimensional (3D metal substrates and a high specific area capacitance, and area energy density is obtained with hierarchically porous Ni monolith synthesized through a controlled combustion procedure.

  15. Antireflective sub-wavelength structures for improvement of the extraction efficiency and color rendering index of monolithic white light-emitting diode

    DEFF Research Database (Denmark)

    Ou, Yiyu; Corell, Dennis Dan; Dam-Hansen, Carsten

    2011-01-01

    simulation results show that a moth-eye structure enhances the light extraction efficiency over the entire visible light range with an extraction efficiency enhancement of up to 26 %. Also for the first time to our best knowledge, the influence of sub-wavelength structures on both the color rendering index......We have theoretically investigated the influence of antireflective sub-wavelength structures on a monolithic white light-emitting diode (LED). The simulation is based on the rigorous coupled wave analysis (RCWA) algorithm, and both cylinder and moth-eye structures have been studied in the work. Our...... (CRI) and the correlated color temperature (CCT) of the monolithic white LED have been demonstrated. The CRI of the monolithic white LED could be improved from 92.68 to around 94 by applying a cylinder structure, and the CCT could be modified in a very large range with appropriate design...

  16. Compatibility study towards monolithic self-charging power unit based on all-solid thin-film solar module and battery

    Science.gov (United States)

    Sandbaumhüter, Florian; Agbo, Solomon N.; Tsai, Chih-Long; Astakhov, Oleksandr; Uhlenbruck, Sven; Rau, Uwe; Merdzhanova, Tsvetelina

    2017-10-01

    Aiming at the development of a monolithic integrated all-solid-state self-rechargeable power unit, we perform a V-I characteristics compatibility study for the integration of such a device having a thin-film silicon multi-junction photovoltaic (PV) module and a thin-film solid Li//lithium phosphorus oxynitride//LiCoO2 battery. The battery and PV module are connected to mimic a monolithic module-to-storage cell device and the performance of this device in various temperature conditions has been tested. Few issues regarding the matching of the battery and PV module characteristics are identified for improvement. The concept of the integrated all-solid-state PV-battery solution appears viable especially in three-terminal device configuration.

  17. Two-dimensional thermal modeling of power monolithic microwave integrated circuits (MMIC's)

    Science.gov (United States)

    Fan, Mark S.; Christou, Aris; Pecht, Michael G.

    1992-01-01

    Numerical simulations of the two-dimensional temperature distributions for a typical GaAs MMIC circuit are conducted, aiming at understanding the heat conduction process of the circuit chip and providing temperature information for device reliability analysis. The method used is to solve the two-dimensional heat conduction equation with a control-volume-based finite difference scheme. In particular, the effects of the power dissipation and the ambient temperature are examined, and the criterion for the worst operating environment is discussed in terms of the allowed highest device junction temperature.

  18. Monolithic 3D titania with ultrathin nanoshell structures for enhanced photocatalytic activity and recyclability

    Science.gov (United States)

    Ahn, Changui; Park, Junyong; Kim, Donghyuk; Jeon, Seokwoo

    2013-10-01

    Titania has attracted considerable interest for use in water purification applications due to its excellent photocatalytic activity. To further improve the efficiency of photocatalysis, numerous nanostructures (i.e. nanoparticles, nanotubes, and nanowires) have been proposed to increase the surface area of titania. Despite the high photocatalytic performance of the nanostructured titania, subsequent difficulties encountered in recollection and reuse of titania inhibit the practical application for water purification systems. Here we successfully fabricate monolithic, three dimensional (3D) nanoshell titania with high uniformity over large areas (~1 × 1 inch2) through proximity field nanopatterning (PnP) and low-temperature atomic layer deposition (ALD) techniques. The higher surface area of 3D nanoshell titania increases the photocatalytic performance more than three-fold relative to that of a thin film of equivalent sample size. Also, the monolithic form of titania enables it to be reused without any degradation of photocatalytic activity. The newly developed nanomaterials in this study can serve as an efficient and reusable photocatalyst for water purification systems.Titania has attracted considerable interest for use in water purification applications due to its excellent photocatalytic activity. To further improve the efficiency of photocatalysis, numerous nanostructures (i.e. nanoparticles, nanotubes, and nanowires) have been proposed to increase the surface area of titania. Despite the high photocatalytic performance of the nanostructured titania, subsequent difficulties encountered in recollection and reuse of titania inhibit the practical application for water purification systems. Here we successfully fabricate monolithic, three dimensional (3D) nanoshell titania with high uniformity over large areas (~1 × 1 inch2) through proximity field nanopatterning (PnP) and low-temperature atomic layer deposition (ALD) techniques. The higher surface area of 3D

  19. Comparison of the Structural Performance of Monolithic and Precast Reinforced Concrete Core Walls

    OpenAIRE

    Nakachi, Tadaharu

    2014-01-01

    In the core wall system in high-rise buildings, the four L-shaped core walls at the center effectively reduce seismic vibration. On the other hand, precast core walls are effective for construction because they can be built more quickly than cast-in-place core walls. In this study, a lateral loading test was conducted on a monolithic wall column simulating the corner and the area near the corner of an L-shaped core wall. The test results were compared with those of a precast wall column teste...

  20. Monolithic solid oxide fuel cell technology advancement for coal-based power generation. Quarterly technical status report, January--March 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-14

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  1. Biobased monoliths for adenovirus purification.

    Science.gov (United States)

    Fernandes, Cláudia S M; Gonçalves, Bianca; Sousa, Margarida; Martins, Duarte L; Barroso, Telma; Pina, Ana Sofia; Peixoto, Cristina; Aguiar-Ricardo, Ana; Roque, A Cecília A

    2015-04-01

    Adenoviruses are important platforms for vaccine development and vectors for gene therapy, increasing the demand for high titers of purified viral preparations. Monoliths are macroporous supports regarded as ideal for the purification of macromolecular complexes, including viral particles. Although common monoliths are based on synthetic polymers as methacrylates, we explored the potential of biopolymers processed by clean technologies to produce monoliths for adenovirus purification. Such an approach enables the development of disposable and biodegradable matrices for bioprocessing. A total of 20 monoliths were produced from different biopolymers (chitosan, agarose, and dextran), employing two distinct temperatures during the freezing process (-20 °C and -80 °C). The morphological and physical properties of the structures were thoroughly characterized. The monoliths presenting higher robustness and permeability rates were further analyzed for the nonspecific binding of Adenovirus serotype 5 (Ad5) preparations. The matrices presenting lower nonspecific Ad5 binding were further functionalized with quaternary amine anion-exchange ligand glycidyltrimethylammonium chloride hydrochloride by two distinct methods, and their performance toward Ad5 purification was assessed. The monolith composed of chitosan and poly(vinyl) alcohol (50:50) prepared at -80 °C allowed 100% recovery of Ad5 particles bound to the support. This is the first report of the successful purification of adenovirus using monoliths obtained from biopolymers processed by clean technologies.

  2. Hierarchically structured monolithic silicalite-1 consisting of crystallized nanoparticles and its performance in the Beckmann rearrangement of cyclohexanone oxime.

    Science.gov (United States)

    Li, Wen-Cui; Lu, An-Hui; Palkovits, Regina; Schmidt, Wolfgang; Spliethoff, Bernd; Schüth, Ferdi

    2005-09-14

    In this study, we present a synthetic pathway for the fabrication of self-supporting zeolite monoliths consisting of crystallized nanoparticles. A resorcinol-formaldehyde-based organic aerogel is used as a template, and silicalite-1 is used as the zeolite example. The silicalite-1 monoliths obtained consist of individual well-defined zeolite nanocrystals with sizes of 30-40 nm. The monoliths exhibit a high mechanical stability and have hierarchical porosity, with micropores within the zeolite particles, a mesopore system formed by the packing of the nanoparticles, and a macropore system on the monolith level. Such monolithic zeolites show high selectivity typically above 80% to epsilon-caprolactam combined with a high rate of reaction of 0.46 g(caprolactame)/(g(catalyst).h) in the Beckmann rearrangement of cyclohexanone oxime.

  3. Highly bioactive polysiloxane modified bioactive glass-poly(ethylene glycol) hybrids monoliths with controlled surface structure for bone tissue regeneration

    Science.gov (United States)

    Chen, Jing; Que, Wenxiu; Xing, Yonglei; Lei, Bo

    2015-03-01

    Crack-free monoliths with controllable surface microstructure have high bioactivities and therefore potential applications in bone tissue regeneration. In this paper, crack-free polydimethylsiloxane-modified bioactive glass-poly (ethylene glycol) (PDMS-BG-PEG) hybrids monoliths were fabricated via using a modified sol-gel process. Results show that the addition of PEG plays an important part in the formation of crack-free and gelation of the monoliths, and surface microstructures of the as-prepared hybrid monoliths were significantly influenced by the concentration and molecular weight of PEG. The samples obtained from PEG 300 had porous surface result in higher bioactivity (apatite formation) in simulated body fluid (SBF), while the samples obtained from PEG 600 had the smooth surface and inhibited the formation of apatite layer in SBF. These as-prepared hybrid monoliths can be used as a good candidate of implant and scaffold for highly efficient bone tissue regeneration.

  4. 叉指结构在单片晶体滤波器中的应用%Application of interdigital structure in monolithic crystal filters

    Institute of Scientific and Technical Information of China (English)

    孙峰; 张忠友

    2013-01-01

    剖析了一种复合型宽带单片式晶体滤波器.从单片晶体滤波器和叉指换能器的原理出发对该滤波器进行了理论分析,然后使用仿真软件模拟了叉指结构对单片式晶体滤波器的影响.最后通过实验证明了插指结构对晶体滤波器具有调整矩形系数,增加带外抑制和频率微调的作用.%A composite broadband monolithic crystal filter is analyzed. The paper begins with a description of the principle of monolithic crystal filters and interdigital transducer, followed by a therotecial analysis of the filter. A simulation software is used to simulate the impact of interdigital structure on monolithic crystal filters. Finally, the experiment shows that the interpola-tion structure improves the rectangular coefficient and increases out-band rejection and frequency fine tuning for the monolithic crystal filter.

  5. Monolithic mode locked DBR laser with multiple-bandgap MQW structure realized by selective area growth

    Energy Technology Data Exchange (ETDEWEB)

    Schilling, M.; Bouayad-Amine, J.; Feeser, T.; Haisch, H.; Kuehn, E.; Lach, E.; Satzke, K.; Weber, J.; Zielinski, E. [Alcatel Telecom, Stuttgart (Germany). Research Div.

    1996-12-31

    The realization of novel monolithically integrated multiple-segment pulse laser sources in InGaAsP MQW technology is reported. The MQW layers for all functional sections of these devices, the modulator, the active (gain) and the passive waveguide, as well as the Bragg section were grown in a single selective area growth (SAG) step by LP-MOVPE on SiO{sub 2} patterned 2 inch InP substrates. Due to a properly selected pattern geometry 3 different bandgap regions with smooth interfaces are thereby formed along the laser cavity. The more than 4 mm long DBR lasers which exhibit a threshold current as low as 30 mA were mode locked by an intra-cavity electroabsorption modulator applying a sinusoidal voltage at around 10 GHz. In this way an optical pulse train with pulse widths < 13 ps (measured with a streak camera) and high extinction ratio was generated. A time-bandwidth product of 0.5 close to the Fourier limit is obtained. This device is very attractive for signal generation in 40 Gb/s OTDM transmission systems at 1.55 {micro}m wavelength.

  6. Graphene-supported metal oxide monolith

    Energy Technology Data Exchange (ETDEWEB)

    Worsley, Marcus A.; Baumann, Theodore F.; Biener, Juergen; Biener, Monika A.; Wang, Yinmin; Ye, Jianchao; Tylski, Elijah

    2017-01-10

    A composition comprising at least one graphene-supported metal oxide monolith, said monolith comprising a three-dimensional structure of graphene sheets crosslinked by covalent carbon bonds, wherein the graphene sheets are coated by at least one metal oxide such as iron oxide or titanium oxide. Also provided is an electrode comprising the aforementioned graphene-supported metal oxide monolith, wherein the electrode can be substantially free of any carbon-black and substantially free of any binder.

  7. Graphene-supported metal oxide monolith

    Science.gov (United States)

    Worsley, Marcus A.; Baumann, Theodore F.; Biener, Juergen; Biener, Monika A.; Wang, Yinmin; Ye, Jianchao; Tylski, Elijah

    2017-01-10

    A composition comprising at least one graphene-supported metal oxide monolith, said monolith comprising a three-dimensional structure of graphene sheets crosslinked by covalent carbon bonds, wherein the graphene sheets are coated by at least one metal oxide such as iron oxide or titanium oxide. Also provided is an electrode comprising the aforementioned graphene-supported metal oxide monolith, wherein the electrode can be substantially free of any carbon-black and substantially free of any binder.

  8. Pressure drop in CIM disk monolithic columns.

    Science.gov (United States)

    Mihelic, Igor; Nemec, Damjan; Podgornik, Ales; Koloini, Tine

    2005-02-11

    Pressure drop analysis in commercial CIM disk monolithic columns is presented. Experimental measurements of pressure drop are compared to hydrodynamic models usually employed for prediction of pressure drop in packed beds, e.g. free surface model and capillary model applying hydraulic radius concept. However, the comparison between pressure drop in monolith and adequate packed bed give unexpected results. Pressure drop in a CIM disk monolithic column is approximately 50% lower than in an adequate packed bed of spheres having the same hydraulic radius as CIM disk monolith; meaning they both have the same porosity and the same specific surface area. This phenomenon seems to be a consequence of the monolithic porous structure which is quite different in terms of the pore size distribution and parallel pore nonuniformity compared to the one in conventional packed beds. The number of self-similar levels for the CIM monoliths was estimated to be between 1.03 and 2.75.

  9. Monolithic solid oxide fuel cell technology advancement for coal-based power generation. Final report, September 1989--March 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    This project has successfully advanced the technology for MSOFCs for coal-based power generation. Major advances include: tape-calendering processing technology, leading to 3X improved performance at 1000 C; stack materials formulations and designs with sufficiently close thermal expansion match for no stack damage after repeated thermal cycling in air; electrically conducting bonding with excellent structural robustness; and sealants that form good mechanical seals for forming manifold structures. A stack testing facility was built for high-spower MSOFC stacks. Comprehensive models were developed for fuel cell performance and for analyzing structural stresses in multicell stacks and electrical resistance of various stack configurations. Mechanical and chemical compatibility properties of fuel cell components were measured; they show that the baseline Ca-, Co-doped interconnect expands and weakens in hydrogen fuel. This and the failure to develop adequate sealants were the reason for performance shortfalls in large stacks. Small (1-in. footprint) two-cell stacks were fabricated which achieved good performance (average area-specific-resistance 1.0 ohm-cm{sup 2} per cell); however, larger stacks had stress-induced structural defects causing poor performance.

  10. Droop-Free, Reliable, and High-Power InGaN/GaN Nanowire Light-Emitting Diodes for Monolithic Metal-Optoelectronics

    KAUST Repository

    Zhao, Chao

    2016-07-28

    A droop-free nitride light-emitting diode (LED) with the capacity to operate beyond the “green gap” has been a subject of intense scientific and engineering interest. While several properties of nanowires on silicon make them promising for use in LED development, the high aspect ratio of individual nanowires and their laterally discontinuous features limit phonon transport and device performance. Here, we report on the monolithic integration of metal heat-sink and droop-free InGaN/GaN quantum-disks-in-nanowire LEDs emitting at ∼710 nm. The reliable operation of our uncooled nanowire-LEDs (NW-LEDs) epitaxially grown on molybdenum was evident in the constant-current soft burn-in performed on a 380 μm × 380 μm LED. The square LED sustained 600 mA electrical stress over an 8 h period, providing stable light output at maturity without catastrophic failure. The absence of carrier and phonon transport barriers in NW-LEDs was further inferred from current-dependent Raman measurements (up to 700 mA), which revealed the low self-heating. The radiative recombination rates of NW-LEDs between room temperature and 40 °C was not limited by Shockley–Read–Hall recombination, Auger recombination, or carrier leakage mechanisms, thus realizing droop-free operation. The discovery of reliable, droop-free devices constitutes significant progress toward the development of nanowires for practical applications. Our monolithic approach realized a high-performance device that will revolutionize the way high power, low-junction-temperature LED lamps are manufactured for solid-state lighting and for applications in high-temperature harsh environment.

  11. A Distributed Model of Four-Port Monolithic Transformer

    OpenAIRE

    Lee, Dong Ho; Ko, Sangsoo; Jeon, Sang-Hoon; Park, Jae-Woo; Hong, Songcheol

    2004-01-01

    This paper deals with modeling of a monolithic spiral transformer. The transformer is designed and fabricated as a symmetrical octagonal spiral structure using two-metal layer process on GaAs substrate for input balun applications of 2 GHz and 5 GHz push-pull power amplifiers. A distributed model of the transformer is developed to fit in wide frequency range with four ports. The model includes the skin effect which describes increase in series resistance with frequency. Six different se...

  12. Monoliths in Bioprocess Technology

    Directory of Open Access Journals (Sweden)

    Vignesh Rajamanickam

    2015-04-01

    Full Text Available Monolithic columns are a special type of chromatography column, which can be used for the purification of different biomolecules. They have become popular due to their high mass transfer properties and short purification times. Several articles have already discussed monolith manufacturing, as well as monolith characteristics. In contrast, this review focuses on the applied aspect of monoliths and discusses the most relevant biomolecules that can be successfully purified by them. We describe success stories for viruses, nucleic acids and proteins and compare them to conventional purification methods. Furthermore, the advantages of monolithic columns over particle-based resins, as well as the limitations of monoliths are discussed. With a compilation of commercially available monolithic columns, this review aims at serving as a ‘yellow pages’ for bioprocess engineers who face the challenge of purifying a certain biomolecule using monoliths.

  13. Monolithic microchannel heatsink

    Science.gov (United States)

    Benett, William J.; Beach, Raymond J.; Ciarlo, Dino R.

    1996-01-01

    A silicon wafer has slots sawn in it that allow diode laser bars to be mounted in contact with the silicon. Microchannels are etched into the back of the wafer to provide cooling of the diode bars. To facilitate getting the channels close to the diode bars, the channels are rotated from an angle perpendicular to the diode bars which allows increased penetration between the mounted diode bars. This invention enables the fabrication of monolithic silicon microchannel heatsinks for laser diodes. The heatsinks have low thermal resistance because of the close proximity of the microchannels to the laser diode being cooled. This allows high average power operation of two-dimensional laser diode arrays that have a high density of laser diode bars and therefore high optical power density.

  14. Analysis and characterizations of planar transmission structures and components for superconducting and monolithic integrated circuits

    Science.gov (United States)

    Itoh, Tatsuo

    1992-01-01

    The research effort was continued to design and characterize superconducting transmission line structures. The research during this period was concentrated on the implementation of a superconductor into coplanar waveguide structures. First, the superconducting coplanar waveguide was examined, and compared with a superconducting microstrip line in terms of loss characteristics and their design aspects. Then, the research was carried on the design and characterization of the coplanar waveguide family in the packaging environment. The transition between the coaxial line to the conductor backed coplanar waveguide was also designed for the measurement of the superconducting conductor backed coplanar waveguide.

  15. High Performance and Low power Monolithic Three-Dimensional Sub-50 nm Poly Si Thin film transistor (TFTs) Circuits.

    Science.gov (United States)

    Wu, Tsung-Ta; Huang, Wen-Hsien; Yang, Chih-Chao; Chen, Hung-Chun; Hsieh, Tung-Ying; Lin, Wei-Sheng; Kao, Ming-Hsuan; Chen, Chiu-Hao; Yao, Jie-Yi; Jian, Yi-Ling; Hsu, Chiung-Chih; Lin, Kun-Lin; Shen, Chang-Hong; Chueh, Yu-Lun; Shieh, Jia-Min

    2017-05-02

    Development of manufacture trend for TFTs technologies has focused on improving electrical properties of films with the cost reduction to achieve commercialization. To achieve this goal, high-performance sub-50 nm TFTs-based MOSFETs with ON-current (Ion)/subthreshold swing (S.S.) of 181 µA/µm/107 mV/dec and 188 µA/µm/98 mV/dec for NMOSFETs and PMOSFETs in a monolithic 3D circuit were demonstrated by a low power with low thermal budget process. In addition, a stackable static random access memory (SRAM) integrated with TFTs-based MOSFET with static noise margins (SNM) equals to 390 mV at VDD = 1.0 V was demonstrated. Overall processes include a low thermal budget via ultra-flat and ultra-thin poly-Si channels by solid state laser crystallization process, chemical-mechanical polishing (CMP) planarization, plasma-enhanced atomic layer deposition (ALD) gate stacking layers and infrared laser activation with a low thermal budget. Detailed material and electrical properties were investigated. The advanced 3D architecture with closely spaced inter-layer dielectrics (ILD) enables high-performance stackable MOSFETs and SRAM for power-saving IoT/mobile products at a low cost or flexible substrate.

  16. A space imaging concept based on a 4m structured spun-cast borosilicate monolithic primary mirror

    Science.gov (United States)

    West, S. C.; Bailey, S. H.; Bauman, S.; Cuerden, B.; Granger, Z.; Olbert, B. H.

    2010-07-01

    Lockheed Martin Corporation (LMC) tasked The University of Arizona Steward Observatory (UASO) to conduct an engineering study to examine the feasibility of creating a 4m space telescope based on mature borosilicate technology developed at the UASO for ground-based telescopes. UASO has completed this study and concluded that existing launch vehicles can deliver a 4m monolithic telescope system to a 500 km circular orbit and provide reliable imagery at NIIRS 7-8. An analysis of such an imager based on a lightweight, high-performance, structured 4m primary mirror cast from borosilicate glass is described. The relatively high CTE of this glass is used to advantage by maintaining mirror shape quality with a thermal figuring method. Placed in a 290 K thermal shroud (similar to the Hubble Space Telescope), the orbit averaged figure surface error is 6nm rms when earth-looking. Space-looking optical performance shows that a similar thermal conditioning scheme combined with a 270 K shroud achieves primary mirror distortion of 10 nm rms surface. Analysis shows that a 3-point bipod mount will provide launch survivability with ample margin. The primary mirror naturally maintains its shape at 1g allowing excellent end-to-end pre-launch testing with e.g. the LOTIS 6.5m Collimator. The telescope includes simple systems to measure and correct mirror shape and alignment errors incorporating technologies already proven on the LOTIS Collimator. We have sketched a notional earth-looking 4m telescope concept combined with a wide field TMA concept into a DELTA IV or ATLAS 552 EELV fairing. We have combined an initial analysis of launch and space performance of a special light-weighted honeycomb borosilicate mirror (areal density 95 kg/m2) with public domain information on the existing launch vehicles.

  17. Development of monolith with a carbon-nanofiber-washcoat as a structured catalyst support in liquid phase

    NARCIS (Netherlands)

    Jarrah, Nabeel A.; Ommen, van J.G.; Lefferts, L.

    2003-01-01

    Washcoats with improved mass transfer properties are necessary to circumvent concentration gradients in case of fast reactions in liquid phase, e.g. nitrate hydrogenation. A highly porous, high surface area (180 m2/g) and thin washcoat of carbon fibers, was produced on a monolith support by methane

  18. Efficient, High-Speed, Monolithic Optoelectronic Circuits Using Quantum- Confined Structures

    Science.gov (United States)

    1991-07-25

    made to optimize the ridge-waveguide laser fabrication process by working on GaAs and In0.2Ga0.sAs single quantum- laser monitoring and polyimidc...with and without a SSL active layer. Because the SSL laser samples are precious, a special effort has been made to optimize the ridge-waveguide laser ... fabrication process by working on GaAs and Ino.2Ga0.sAs single quantum- 20 well SCH structures. It is found that the choice among SiQz, SixNy and

  19. Fabrication and characterization of monolithic solid oxide fuel cells

    Science.gov (United States)

    Minh, N. Q.; Horne, C. R.; Liu, F. S.; Moffatt, D. M.; Staszak, P. R.

    The monolithic solid oxide fuel cell (MSOFC) is an all-ceramic structure in which cell components are configured in a compact corrugated array. The MSOFC shows promise for use in a wide range of sizes (kilowatt to megawatt) and a broad spectrum of applications (electric utility, cogeneration, on-site, and aerospace power). A process based on the tape calendering technique is being developed for the fabrication of the MSOFC. MSOFC single cells have been fabricated by this process without cracking or delamination. Stacks of various sizes have been formed and processed to demonstrate fabricability of the monolithic structure. Extensive physical, chemical, electrical, and electrochemical characterization of fabricated samples has been carried out to confirm the required properties of each cell component. The characterization results reported have been used to support material and fabrication improvements.

  20. 单片集成微波/射频功率放大器技术进展%Progress in Monolithic Integrated Microwave/RF Power Amplifier

    Institute of Scientific and Technical Information of China (English)

    李强; 严利人; 周卫; 张伟

    2011-01-01

    As wireless communication market increases, monolithic integrated microwave/RF power amplifier (MMIC PA) plays a more and more important role in 3G and/or 4G systems. Traditional circuits used in mono-stage amplifiers are reviewed, together with their pros and cons. Architectures, such as the Doherty circuitry, EER (Envelope Elimination and Restoration) technology, LINC, etc. , are also discussed. Generally, these technologies may be used to improve linearity and efficiency of microwave power amplifier. Currently, some system-level linearization techniques have also been utilized. The overview may serve as a useful groundwork for those who are designing MMIC Pas.%回顾了一些用于微波单级功率放大器的传统技术方案,讨论了各自的优缺点.从电路模块的角度,总结了若干兼顾功放线性度和效率指标的典型电路拓扑形式,包括Doherty电路、包络消除与恢复(EER)技术、LINC技术等,并总结了当前主要采用的基于电路系统层面的微波射频功放线性化方案.在此基础上,列举评点了文献中一些典型功放的电路特点和性能指标,可为设计和制造人员提供有益参考.

  1. Power system damping - Structural aspects of controlling active power

    Energy Technology Data Exchange (ETDEWEB)

    Samuelsson, O.

    1997-04-01

    Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. A consequence is that power system damping is reduced, leading to a risk of poorly damped power oscillations between the generators. This thesis proposes the use of controlled active loads to increase damping of such electro-mechanical oscillations. The focus is on structural aspects of controller interaction and of sensor and actuator placement. On-off control based on machine frequency in a single machine infinite bus system is analysed using energy function analysis and phase plane plots. An on-off controller with estimated machine frequency as input has been implemented. At a field test it damped oscillations of a 0.9 MW hydro power generator by controlling a 20kW load. The linear analysis uses two power system models with three and twenty-three machines respectively. Each damper has active power as output and local bus frequency or machine frequency as input. The power system simulator EUROSTAG is used both for generation of the linearized models and for time simulations. Measures of active power mode controllability and phase angle mode observability are obtained from the eigenvectors of the differential-algebraic models. The geographical variation in the network of these quantities is illustrated using the resemblance to bending modes of flexible mechanical structures. Eigenvalue sensitivities are used to determine suitable damper locations. A spring-mass equivalent to an inter-area mode provides analytical expressions, that together with the concept of impedance matching explain the structural behaviour of the power systems. For large gains this is investigated using root locus plots. 64 refs, 99 figs, 20 tabs

  2. Monolithically Peltier-cooled laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Hava, S.; Hunsperger, R.G.; Sequeira, H.B.

    1984-04-01

    A new method of cooling a GaAs/GaAlAs laser in an optical integrated circuit or on a discrete chip, by adding an integral thermoelectric (Peltier) cooling and heat spreading device to the laser, is presented. This cooling both reduces and stabilizes the laser junction temperature to minimize such deleterious effects as wavelength drift due to heating. A unified description of the electrical and thermal properties of a monolithic semiconductor mesa structure is given. Here it is shown that an improvement in thermal characteristics is obtained by depositing a relatively thick metallic layer, and by using this layer as a part of an active Peltier structure. Experimental results reveal a 14-percent increase in emitted power (external quantum efficiency) due to passive heat spreading and a further 8-percent if its Peltier cooler is operated. Fabrication techniques used to obtain devices exhibiting the above performance characteristics are given. 21 references.

  3. Crystallinity and stoichiometry of nano-structured sol-gel-derived BaTiO{sub 3} monolithic gels

    Energy Technology Data Exchange (ETDEWEB)

    Shimooka, Hirokazu [Kyushu Inst. of Tech., Kitakyushu, Fukuoka (Japan). Dept. of Applied Chemistry; Kuwabara, Makoto [Univ. of Tokyo (Japan). Dept. of Materials Science

    1996-11-01

    The crystallization behavior and stoichiometric changes of barium titanium alkoxide-derived monolithic gels prepared by the sol-gel process using a high-concentration Ba,Ti precursor solution (0.8 mol/L) were investigated during aging at room temperature. Crystallization of the gels (which were amorphous, per X-ray diffraction analysis immediately after gelation) into the BaTiO{sub 3} perovskite phase increased during aging and was associated with significant shrinkage of the gels. Crystallization reached a value of {approximately}82% by the final stage of shrinkage, assuming the degree of crystallization of a gel treated at 600 C to be 100%. The stoichiometry of the gels (Ba/Ti molar ratio) also changed considerably during aging, as estimated by the concentrations of Ba and Ti that remained in the expelled liquid resulting from syneresis at any time during the aging process. Deviation in the Ba/Ti ratio of the precursor solution ranged from 0.015 at the initial stage of shrinkage to 0.003 at the final stage, a value determined by inductively coupled plasma atomic emission spectroscopy. The present study demonstrates the great advantage of using high-concentration precursor solutions of barium titanium alkoxides, rather than low-concentration solutions, to obtain BaTiO{sub 3} gel monoliths with high density and crystallinity and little stoichiometric deviation, by sol-gel processing at room temperature.

  4. A new switched power linac structure

    Energy Technology Data Exchange (ETDEWEB)

    Villa, F.

    1989-03-01

    A new pulse power structure has been described that utilizes an easily accessible rectilinear switch. The new structure is more ''forgiving'' (as far as risetime is concerned) than the radial line transformer, and contains fewer switching structures/unit length. The combination of the new structure with the switch proposed seems to offer interesting possibilities for a future linear collider. 13 refs., 6 figs., 2 tabs.

  5. The features of ceramic materials structure formation when using hard-melting wastes of thermal power stations in charge stock

    Science.gov (United States)

    Skripnikova, Nelli; Yuriev, Ivan; Lutsenko, Alexander; Litvinova, Viktoriya

    2016-01-01

    The paper presents the analysis of aluminum silicate waste generated by thermal power station of the city of Seversk, Tomsk region, Russia. The chemical compositions of aluminum silicate waste are detected and the efficient mixture compositions with the addition of aluminum silicate waste are suggested herein. Ceramic brick structure formation is studied in this paper using X-ray phase and SEM analyses. It is identified that the formed vitreous phase facilitates such strengthening structural modifications as sintering out of pores and shrinkage of unmelted aluminum silicate particles with the following formation of a monolithic product.

  6. Information Handling, Organizational Structure, and Power.

    Science.gov (United States)

    Buckland, Michael K.

    1989-01-01

    Uses examples from military strategic communications to demonstrate that organizational structures and the distribution of power within organizational structures adapt to changes in information handling capability. It is concluded that delegation and decentralization can be viewed as indicative of inadequate information handling and that improved…

  7. Mechanically stable, hierarchically porous Cu3(btc)2 (HKUST-1) monoliths via direct conversion of copper(II) hydroxide-based monoliths.

    Science.gov (United States)

    Moitra, Nirmalya; Fukumoto, Shotaro; Reboul, Julien; Sumida, Kenji; Zhu, Yang; Nakanishi, Kazuki; Furukawa, Shuhei; Kitagawa, Susumu; Kanamori, Kazuyoshi

    2015-02-28

    The synthesis of highly crystalline macro-meso-microporous monolithic Cu3(btc)2 (HKUST-1; btc(3-) = benzene-1,3,5-tricarboxylate) is demonstrated by direct conversion of Cu(OH)2-based monoliths while preserving the characteristic macroporous structure. The high mechanical strength of the monoliths is promising for possible applications to continuous flow reactors.

  8. Activated Carbon Fiber Monoliths as Supercapacitor Electrodes

    Directory of Open Access Journals (Sweden)

    Gelines Moreno-Fernandez

    2017-01-01

    Full Text Available Activated carbon fibers (ACF are interesting candidates for electrodes in electrochemical energy storage devices; however, one major drawback for practical application is their low density. In the present work, monoliths were synthesized from two different ACFs, reaching 3 times higher densities than the original ACFs’ apparent densities. The porosity of the monoliths was only slightly decreased with respect to the pristine ACFs, the employed PVDC binder developing additional porosity upon carbonization. The ACF monoliths are essentially microporous and reach BET surface areas of up to 1838 m2 g−1. SEM analysis reveals that the ACFs are well embedded into the monolith structure and that their length was significantly reduced due to the monolith preparation process. The carbonized monoliths were studied as supercapacitor electrodes in two- and three-electrode cells having 2 M H2SO4 as electrolyte. Maximum capacitances of around 200 F g−1 were reached. The results confirm that the capacitance of the bisulfate anions essentially originates from the double layer, while hydronium cations contribute with a mixture of both, double layer capacitance and pseudocapacitance.

  9. Optimization of Thermo electric Microwave Power Sensors Based on Thin-Membrane Structure

    Institute of Scientific and Technical Information of China (English)

    WANG Debo; GAO Bo; ZHAO Jiang; ZHANG Yi; GUO Yanyan

    2015-01-01

    In this work, the thermal conduction prop-erty of thermoelectric microwave power sensors is re-searched. The fabrication of the thermoelectric microwave power sensor consists of a front side and a back side pro-cessing using GaAs Monolithic microwave integrated cir-cuit (MMIC) process and MEMS technology. An isolation structure on the front side is designed to prevent the ther-mal conduction from the resistor to the Coplanar waveg-uide (CPW). A thin-membrane on the back side is de-signed to prevent the thermal conduction from the resistor to the substrate. For the microwave power sensor without an isolation structure, the sensitivity is about 0.138, 0.136, 0.132, 0.115 and 0.111mV/mW at 8, 9, 10, 11 and 12GHz, respectively. For the microwave power sensor with an isola-tion structure, the sensitivity is about 0.142, 0.139, 0.135, 0.117 and 0.115mV/mW at 8, 9, 10, 11 and 12GHz, respec-tively. As a result, the higher thermal conduction efficiency and the higher sensitivity are obtained for the optimized thermoelectric microwave power sensors.

  10. Fabrication of Si/SiO2/GaN structure by surface-activated bonding for monolithic integration of optoelectronic devices

    Science.gov (United States)

    Tsuchiyama, Kazuaki; Yamane, Keisuke; Sekiguchi, Hiroto; Okada, Hiroshi; Wakahara, Akihiro

    2016-05-01

    A Si/SiO2/GaN-light-emitting-diode (LED) wafer is proposed as a new structure for the monolithic integration of both Si circuits and GaN-based optical devices. Surface-activated bonding was performed to transfer a Si layer from a silicon-on-insulator substrate to a SiO2/GaN-LED substrate. Transmission electron microscopy observation revealed that a defect-free Si layer was formed on the SiO2/GaN-LED substrate without interfacial voids. The crystalline quality of the Si layer, which is characterized by an X-ray rocking curve, was markedly improved by flattening the SiO2/GaN-LED substrate before bonding. Finally, a micro-LED array was successfully fabricated on the Si/SiO2/GaN-LED wafer without the delamination of the Si layer.

  11. Monolithic integration of enhancement-mode vertical driving transistorson a standard InGaN/GaN light emitting diode structure

    Science.gov (United States)

    Lu, Xing; Liu, Chao; Jiang, Huaxing; Zou, Xinbo; Zhang, Anping; Lau, Kei May

    2016-08-01

    In this letter, monolithic integration of InGaN/GaN light emitting diodes (LEDs) with vertical metal-oxide-semiconductor field effect transistor (VMOSFET) drivers have been proposed and demonstrated. The VMOSFET was achieved by simply regrowing a p- and n-GaN bilayer on top of a standard LED structure. After fabrication, the VMOSFET is connected with the LED through the conductive n-GaN layer, with no need of extra metal interconnections. The junction-based VMOSFET is inherently an enhancement-mode (E-mode) device with a threshold voltage of 1.6 V. By controlling the gate bias of the VMOSFET, the light intensity emitted from the integrated VMOSFET-LED device could be well modulated, which shows great potential for various applications, including solid-state lighting, micro-displays, and visible light communications.

  12. AIN Monolithic Microchannel Cooled Heatsink for High Power Laser Diode Array%应用于大功率激光二极管列阵的单片集成微通道制冷热沉

    Institute of Scientific and Technical Information of China (English)

    马杰慧; 方高瞻; 蓝永生; 马骁宇

    2005-01-01

    介绍了一种应用于大功率激光二极管列阵的新型单片集成微通道制冷热沉.这种热沉已制造并经过测试.10叠层的激光二极管列阵的热阻为0.121℃/W.相邻两个激光条的间距是1.17mm.在20%高占空比条件下,波长为808nm左右,峰值功率可以达到611W.%A novel AIN monolithic microchannel cooled heatsink for high power laser diode array is introduced.The high power stack laser diode array with an AIN monolithic microchannel heatsink is fabricated and tested.The thermal impedance of a 10 stack laser diode array is 0.121℃/W.The pitch between two adjacent bars is 1.17mm.The power level of 611W is achieved under the 20% duty factor condition at an emission wavelength around 808nm.

  13. Seismic analysis of nuclear power plant structures

    Science.gov (United States)

    Go, J. C.

    1973-01-01

    Primary structures for nuclear power plants are designed to resist expected earthquakes of the site. Two intensities are referred to as Operating Basis Earthquake and Design Basis Earthquake. These structures are required to accommodate these seismic loadings without loss of their functional integrity. Thus, no plastic yield is allowed. The application of NASTRAN in analyzing some of these seismic induced structural dynamic problems is described. NASTRAN, with some modifications, can be used to analyze most structures that are subjected to seismic loads. A brief review of the formulation of seismic-induced structural dynamics is also presented. Two typical structural problems were selected to illustrate the application of the various methods of seismic structural analysis by the NASTRAN system.

  14. Power Flow and Structure-Borne Noise

    DEFF Research Database (Denmark)

    Wachulec, Marcin

    The method of power flow analysis within a structure depends on the frequency considered. For the low frequencies the standard Finite Element Method (FEM) can be used efficiently. In the high frequencies the Statistical Energy Analysis (SEA) proved its usefulness. The distinction between low and ...... in plane and out of plane of the plate....

  15. Recycling of inorganic waste in monolithic and cellular glass-based materials for structural and functional applications.

    Science.gov (United States)

    Rincón, Acacio; Marangoni, Mauro; Cetin, Suna; Bernardo, Enrico

    2016-07-01

    The stabilization of inorganic waste of various nature and origin, in glasses, has been a key strategy for environmental protection for the last decades. When properly formulated, glasses may retain many inorganic contaminants permanently, but it must be acknowledged that some criticism remains, mainly concerning costs and energy use. As a consequence, the sustainability of vitrification largely relies on the conversion of waste glasses into new, usable and marketable glass-based materials, in the form of monolithic and cellular glass-ceramics. The effective conversion in turn depends on the simultaneous control of both starting materials and manufacturing processes. While silica-rich waste favours the obtainment of glass, iron-rich wastes affect the functionalities, influencing the porosity in cellular glass-based materials as well as catalytic, magnetic, optical and electrical properties. Engineered formulations may lead to important reductions of processing times and temperatures, in the transformation of waste-derived glasses into glass-ceramics, or even bring interesting shortcuts. Direct sintering of wastes, combined with recycled glasses, as an example, has been proven as a valid low-cost alternative for glass-ceramic manufacturing, for wastes with limited hazardousness. The present paper is aimed at providing an up-to-date overview of the correlation between formulations, manufacturing technologies and properties of most recent waste-derived, glass-based materials. © 2016 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  16. Magnetospheric structure of rotation powered pulsars

    Energy Technology Data Exchange (ETDEWEB)

    Arons, J. (California Univ., Berkeley, CA (USA) California Univ., Livermore, CA (USA). Inst. of Geophysics and Planetary Physics)

    1991-01-07

    I survey recent theoretical work on the structure of the magnetospheres of rotation powered pulsars, within the observational constraints set by their observed spindown, their ability to power synchrotron nebulae and their ability to produce beamed collective radio emission, while putting only a small fraction of their energy into incoherent X- and gamma radiation. I find no single theory has yet given a consistent description of the magnetosphere, but I conclude that models based on a dense outflow of pairs from the polar caps, permeated by a lower density flow of heavy ions, are the most promising avenue for future research. 106 refs., 4 figs., 2 tabs.

  17. A monolithic collapse origin for the thin and thick disc structure of the S0 galaxy ESO 243-49

    Science.gov (United States)

    Comerón, S.; Salo, H.; Peletier, R. F.; Mentz, J.

    2016-09-01

    ESO 243-49 is a high-mass (circular velocity vc ≈ 200 km s-1), edge-on S0 galaxy in the Abell 2877 cluster at a distance of ~95 Mpc. To elucidate the origin of the thick disc of this S0 galaxy, we use Multi Unit Spectroscopic Explorer (MUSE) science verification data to study its kinematics and stellar populations. The thick disc emits ~80% of the light at heights in excess of 3.5 arcsec (1.6 kpc). The rotation velocities of its stars lag by 30-40 km s-1 compared to those in the thin disc, which is compatible with the asymmetric drift. The thick disc is found to be more metal-poor than the thin disc, but both discs have old ages. We suggest an internal origin for the thick disc stars in high-mass galaxies. We propose that the thick disc formed either a) first in a turbulent phase with a high star formation rate and that a thin disc formed shortly afterwards, or b) because of the dynamical heating of a thin pre-existing component. Either way, the star formation in ESO 243-49 was quenched just a few Gyr after the galaxy was born and the formation of a thin and a thick disc must have occurred before the galaxy stopped forming stars. The formation of the discs was so fast that it could be described as a monolithic collapse where several generations of stars formed in rapid succession. Based on observations made at the European Southern Observatory using the Very Large Telescope under programme 60.A-9328(A).

  18. Poly(ethylenimine)-Functionalized Monolithic Alumina Honeycomb Adsorbents for CO2 Capture from Air.

    Science.gov (United States)

    Sakwa-Novak, Miles A; Yoo, Chun-Jae; Tan, Shuai; Rashidi, Fereshteh; Jones, Christopher W

    2016-07-21

    The development of practical and effective gas-solid contactors is an important area in the development of CO2 capture technologies. Target CO2 capture applications, such as postcombustion carbon capture and sequestration (CCS) from power plant flue gases or CO2 extraction directly from ambient air (DAC), require high flow rates of gas to be processed at low cost. Extruded monolithic honeycomb structures, such as those employed in the catalytic converters of automobiles, have excellent potential as structured contactors for CO2 adsorption applications because of the low pressure drop imposed on fluid moving through the straight channels of such structures. Here, we report the impregnation of poly(ethylenimine) (PEI), an effective aminopolymer reported commonly for CO2 separation, into extruded monolithic alumina to form structured CO2 sorbents. These structured sorbents are first prepared on a small scale, characterized thoroughly, and compared with powder sorbents with a similar composition. Despite consistent differences observed in the filling of mesopores with PEI between the monolithic and powder sorbents, their performance in CO2 adsorption is similar across a range of PEI contents. A larger monolithic cylinder (1 inch diameter, 4 inch length) is evaluated under conditions closer to those that might be used in large-scale applications and shows a similar performance to the smaller monoliths and powders tested initially. This larger structure is evaluated over five cycles of CO2 adsorption and steam desorption and demonstrates a volumetric capacity of 350 molCO2  m-3monolith and an equilibration time of 350 min under a 0.4 m s(-1) linear flow velocity through the monolith channels using 400 ppm CO2 in N2 as the adsorption gas at 30 °C. This volumetric capacity surpasses that of a similar technology considered previously, which suggested that CO2 could be removed from air at an operating cost as low as $100 per ton.

  19. A wafer-scale packaging structure with monolithic microwave integrated circuits and passives embedded in a silicon substrate for multichip modules for radio frequency applications

    Science.gov (United States)

    Geng, Fei; Ding, Xiao-yun; Xu, Gao-wei; Luo, Le

    2009-10-01

    A wafer-level packaging structure with chips and passive components embedded in a silicon substrate for multichip modules (MCM) is proposed for radio frequency (RF) applications. The packaging structure consists of two layers of benzocyclobutene (BCB) films and three layers of metalized films, in which the monolithic microwave ICs (MMICs), thin film resistors, striplines and microstrip lines are integrated. The low resistivity silicon wafer with etched cavities is used as a substrate. The BCB films serve as interlayer dielectrics (ILDs). Wirebonding gold bumps are used as electric interconnections between different layers, which eliminate the need of preparing vias by costly procedures including dry etching, metal sputtering and electroplating. The chemical mechanical planarization (CMP) is used to uncover the gold bumps, and the BCB curing profile is optimized to obtain the appropriate BCB film for CMP process. In this work, the thermal, mechanical, electrical as well as RF properties of the packaging structure are investigated. The packaging thermal resistance can be controlled below 2 °C W-1. The average shear strength of the gold bumps on the BCB surface is about 70 MPa. In addition, a Kelvin test structure is fabricated for resistance testing of the vertical vias. The performances of MMIC and interconnection structure at high frequency are simulated and tested. The testing results reveal that the slight shifting of S-parameter curves of the packaged MMIC indicates perfect transmission characteristics at high frequency. For the transition structure of transmission line, the experimental results are compatible with the simulation results. The insertion loss (S21) is below 0.4 dB from 0 to 40 GHz and the return loss (S11) is less than -20 dB from 0 to 40 GHz. For a low noise amplifier (LNA) chip, the S21 shifting caused by the packaging structure is below 0.5 dB, and S11 is less than -10 dB from 8 GHz to 14 GHz.

  20. Power mos devices: structures and modelling procedures

    Energy Technology Data Exchange (ETDEWEB)

    Rossel, P.; Charitat, G.; Tranduc, H.; Morancho, F.; Moncoqut

    1997-05-01

    In this survey, the historical evolution of power MOS transistor structures is presented and currently used devices are described. General considerations on current and voltage capabilities are discussed and configurations of popular structures are given. A synthesis of different modelling approaches proposed last three years is then presented, including analytical solutions, for basic electrical parameters such as threshold voltage, on-resistance, saturation and quasi-saturation effects, temperature influence and voltage handling capability. The numerical solutions of basic semiconductor devices is then briefly reviewed along with some typical problems which can be solved this way. A compact circuit modelling method is finally explained with emphasis on dynamic behavior modelling

  1. Study about the Asymmetry Competing Channel Structure under Bargaining Power

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lan; AI Xing-zheng

    2005-01-01

    On the problem of competing channel structure, we present asymmetry competing channel structure models under bargaining power, analyze the evolving process of channel structure under different bargaining power and product nature, find different bargaining power and product nature important role for channel structure, and also present equilibrium result. Furthermore, the academic proof for channel structure choice is presented.

  2. Monolithic integrated optic fiber Bragg grating sensor interrogator

    Science.gov (United States)

    Mendoza, Edgar A.; Esterkin, Yan; Kempen, Cornelia; Sun, Songjian

    2010-04-01

    Fiber Bragg gratings (FBGs) are a mature sensing technology that has gained rapid acceptance in civil, aerospace, chemical and petrochemical, medicine, aviation and automotive industries. Fiber Bragg grating sensors can be use for a variety of measurements including strain, stress, vibration, acoustics, acceleration, pressure, temperature, moisture, and corrosion distributed at multiple locations within the structure using a single fiber element. The most prominent advantages of FBGs are: small size and light weight, multiple FBG transducers on a single fiber, and immunity to radio frequency interference. A major disadvantage of FBG technology is that conventional state-of-the-art fiber Bragg grating interrogation systems are typically bulky, heavy, and costly bench top instruments that are assembled from off-the-shelf fiber optic and optical components integrated with a signal electronics board into an instrument console. Based on the need for a compact FBG interrogation system, this paper describes recent progress towards the development of a miniature fiber Bragg grating sensor interrogator (FBG-TransceiverTM) system based on multi-channel monolithic integrated optic sensor microchip technology. The integrated optic microchip technology enables the monolithic integration of all of the functionalities, both passive and active, of conventional bench top FBG sensor interrogators systems, packaged in a miniaturized, low power operation, 2-cm x 5-cm small form factor (SFF) package suitable for the long-term structural health monitoring in applications where size, weight, and power are critical for operation.

  3. Monolithic microwave integrated circuits

    Science.gov (United States)

    Pucel, R. A.

    Monolithic microwave integrated circuits (MMICs), a new microwave technology which is expected to exert a profound influence on microwave circuit designs for future military systems as well as for the commercial and consumer markets, is discussed. The book contains an historical discussion followed by a comprehensive review presenting the current status in the field. The general topics of the volume are: design considerations, materials and processing considerations, monolithic circuit applications, and CAD, measurement, and packaging techniques. All phases of MMIC technology are covered, from design to testing.

  4. Development of a monolithic ferrite memory array

    Science.gov (United States)

    Heckler, C. H., Jr.; Bhiwandker, N. C.

    1972-01-01

    The results of the development and testing of ferrite monolithic memory arrays are presented. This development required the synthesis of ferrite materials having special magnetic and physical characteristics and the development of special processes; (1) for making flexible sheets (laminae) of the ferrite composition, (2) for embedding conductors in ferrite, and (3) bonding ferrite laminae together to form a monolithic structure. Major problems encountered in each of these areas and their solutions are discussed. Twenty-two full-size arrays were fabricated and fired during the development of these processes. The majority of these arrays were tested for their memory characteristics as well as for their physical characteristics and the results are presented. The arrays produced during this program meet the essential goals and demonstrate the feasibility of fabricating monolithic ferrite memory arrays by the processes developed.

  5. Carbon Fiber Composite Monoliths as Catalyst Supports

    Energy Technology Data Exchange (ETDEWEB)

    Contescu, Cristian I [ORNL; Gallego, Nidia C [ORNL; Pickel, Joseph M [ORNL; Blom, Douglas Allen [ORNL; Burchell, Timothy D [ORNL

    2006-01-01

    Carbon fiber composite monoliths are rigid bodies that can be activated to a large surface area, have tunable porosity, and proven performance in gas separation and storage. They are ideal as catalyst supports in applications where a rigid support, with open structure and easy fluid access is desired. We developed a procedure for depositing a dispersed nanoparticulate phase of molybdenum carbide (Mo2C) on carbon composite monoliths in the concentration range of 3 to 15 wt% Mo. The composition and morphology of this phase was characterized using X-ray diffraction and electron microscopy, and a mechanism was suggested for its formation. Molybdenum carbide is known for its catalytic properties that resemble those of platinum group metals, but at a lower cost. The materials obtained are expected to demonstrate catalytic activity in a series of hydrocarbon reactions involving hydrogen transfer. This project demonstrates the potential of carbon fiber composite monoliths as catalyst supports.

  6. Carbon Fiber Composite Monoliths for Catalyst Supports

    Energy Technology Data Exchange (ETDEWEB)

    Contescu, Cristian I [ORNL; Gallego, Nidia C [ORNL; Pickel, Joseph M [ORNL; Blom, Douglas Allen [ORNL; Burchell, Timothy D [ORNL

    2006-01-01

    Carbon fiber composite monoliths are rigid bodies that can be activated to a large surface area, have tunable porosity, and proven performance in gas separation and storage. They are ideal as catalyst supports in applications where a rigid support, with open structure and easy fluid access is desired. We developed a procedure for depositing a dispersed nanoparticulate phase of molybdenum carbide (Mo2C) on carbon composite monoliths in the concentration range of 3 to 15 wt% Mo. The composition and morphology of this phase was characterized using X-ray diffraction and electron microscopy, and a mechanism was suggested for its formation. Molybdenum carbide is known for its catalytic properties that resemble those of platinum group metals, but at a lower cost. The materials obtained are expected to demonstrate catalytic activity in a series of hydrocarbon reactions involving hydrogen transfer. This project demonstrates the potential of carbon fiber composite monoliths as catalyst supports.

  7. Monolithic pixel detectors for high energy physics

    CERN Document Server

    Snoeys, W

    2013-01-01

    Monolithic pixel detectors integrating sensor matrix and readout in one piece of silicon have revolutionized imaging for consumer applications, but despite years of research they have not yet been widely adopted for high energy physics. Two major requirements for this application, radiation tolerance and low power consumption, require charge collection by drift for the most extreme radiation levels and an optimization of the collected signal charge over input capacitance ratio ( Q / C ). It is shown that monolithic detectors can achieve Q / C for low analog power consumption and even carryout the promise to practically eliminate analog power consumption, but combining suf fi cient Q / C , collection by drift, and integration of readout circuitry within the pixel remains a challenge. An overview is given of different approaches to address this challenge, with possible advantages and disadvantages.

  8. Embedded-monolith armor

    Science.gov (United States)

    McElfresh, Michael W.; Groves, Scott E; Moffet, Mitchell L.; Martin, Louis P.

    2016-07-19

    A lightweight armor system utilizing a face section having a multiplicity of monoliths embedded in a matrix supported on low density foam. The face section is supported with a strong stiff backing plate. The backing plate is mounted on a spall plate.

  9. Monolithic Solid Oxide Fuel Cell development

    Science.gov (United States)

    Myles, K. M.; McPheeters, C. C.

    1989-12-01

    The Monolithic Solid Oxide Fuel Cell (MSOFC) is an oxide-ceramic structure in which appropriate electronic and ionic conductors are fabricated in a honeycomb shape similar to a block of corrugated paperboard. These electronic and ionic conductors are arranged to provide short conduction paths to minimize resistive losses. The power density achievable with the MSOFC is expected to be about 8 kW/kg or 4 kW/L, at fuel efficienceis over 50 percent, because of small cell size and low resistive losses in the materials. The MSOFC operates in the range of 700 to 1000 C, at which temperatures rapid reform of hydrocarbon fuels is expected within the nickel-YSZ fuel channels. Tape casting and hot roll calendering are used to fabricate the MSOFC structure. The performance of the MSOFC has improved significantly during the course of development. The limitation of this system, based on materials resistance alone without interfacial resistances, is 0.093 ohm-sq cm area-specific resistance (ASR). The current typical performance of MSOFC single cells is characterized by ASRs of about 0.4 to 0.5 ohm-sq cm. With further development the ASR is expected to be reduced below 0.2 ohm-sq cm, which will result in power levels greater than 1.4 W/sq cm. The feasibility of the MSOFC concept was proven, and the performance was dramatically improved. The differences in thermal expansion coefficients and firing shrinkages among the fuel cell materials were minimized. As a result of good matching of these properties, the MSOFC structure was successfully fabricated with few defects, and the system shows excellent promise for development into a practical power source.

  10. Inspection of Nuclear Power Plant Containment Structures

    Energy Technology Data Exchange (ETDEWEB)

    Graves, H.L.; Naus, D.J.; Norris, W.E.

    1998-12-01

    Safety-related nuclear power plant (NPP) structures are designed to withstand loadings from a number of low-probability external and interval events, such as earthquakes, tornadoes, and loss-of-coolant accidents. Loadings incurred during normal plant operation therefore generally are not significant enough to cause appreciable degradation. However, these structures are susceptible to aging by various processes depending on the operating environment and service conditions. The effects of these processes may accumulate within these structures over time to cause failure under design conditions, or lead to costly repair. In the late 1980s and early 1990s several occurrences of degradation of NPP structures were discovered at various facilities (e.g., corrosion of pressure boundary components, freeze- thaw damage of concrete, and larger than anticipated loss of prestressing force). Despite these degradation occurrences and a trend for an increasing rate of occurrence, in-service inspection of the safety-related structures continued to be performed in a somewhat cursory manner. Starting in 1991, the U.S. Nuclear Regulatory Commission (USNRC) published the first of several new requirements to help ensure that adequate in-service inspection of these structures is performed. Current regulatory in-service inspection requirements are reviewed and a summary of degradation experience presented. Nondestructive examination techniques commonly used to inspect the NPP steel and concrete structures to identify and quantify the amount of damage present are reviewed. Finally, areas where nondestructive evaluation techniques require development (i.e., inaccessible portions of the containment pressure boundary, and thick heavily reinforced concrete sections are discussed.

  11. Integrated Design and Simulation of Tunable, Multi-State Structures Fabricated Monolithically with Multi-Material 3D Printing

    Science.gov (United States)

    Chen, Tian; Mueller, Jochen; Shea, Kristina

    2017-01-01

    Multi-material 3D printing has created new opportunities for fabricating deployable structures. We design reversible, deployable structures that are fabricated flat, have defined load bearing capacity, and multiple, predictable activated geometries. These structures are designed with a hierarchical framework where the proposed bistable actuator serves as the base building block. The actuator is designed to maximise its stroke length, with the expansion ratio approaching one when serially connected. The activation force of the actuator is parameterised through its joint material and joint length. Simulation and experimental results show that the bistability triggering force can be tuned between 0.5 and 5.0 N. Incorporating this bistable actuator, the first group of hierarchical designs demonstrate the deployment of space frame structures with a tetrahedron module consisting of three active edges, each containing four serially connected actuators. The second group shows the design of flat structures that assume either positive or negative Gaussian curvature once activated. By flipping the initial configuration of the unit actuators, structures such as a dome and an enclosure are demonstrated. A modified Dynamic Relaxation method is used to simulate all possible geometries of the hierarchical structures. Measured geometries differ by less than 5% compared to simulation results. PMID:28361891

  12. Influence of different carbon monolith preparation parameters on pesticide adsorption

    Directory of Open Access Journals (Sweden)

    Vukčević Marija

    2013-01-01

    Full Text Available The capacity of carbon monolith for pesticide removal from water, and the mechanism of pesticide interaction with carbon surface were examined. Different carbon monolith samples were obtained by varying the carbonization and activation parameters. In order to examine the role of surface oxygen groups in pesticide adsorption, carbon monolith surface was functionalized by chemical treatment in HNO3, H2O2 and KOH. The surface properties of the obtained samples were investigated by BET surface area, pore size distribution and temperature-programmed desorption. Adsorption of pesticides from aqueous solution onto activated carbon monolith samples was studied by using five pesticides belonging to different chemical groups (acetamiprid, dimethoate, nicosulfuron, carbofuran and atrazine. Presented results show that higher temperature of carbonization and the amount of activating agent allow obtaining microporous carbon monolith with higher amount of surface functional groups. Adsorption properties of the activated carbon monolith were more readily affected by the amount of the surface functional groups than by specific surface area. Results obtained by carbon monolith functionalisation showed that π-π interactions were the main force for adsorption of pesticides with aromatic structure, while acidic groups play an important role in adsorption of pesticides with no aromatic ring in the chemical structure.

  13. Monolithic MACS micro resonators

    Science.gov (United States)

    Lehmann-Horn, J. A.; Jacquinot, J.-F.; Ginefri, J. C.; Bonhomme, C.; Sakellariou, D.

    2016-10-01

    Magic Angle Coil Spinning (MACS) aids improving the intrinsically low NMR sensitivity of heterogeneous microscopic samples. We report on the design and testing of a new type of monolithic 2D MACS resonators to overcome known limitations of conventional micro coils. The resonators' conductors were printed on dielectric substrate and tuned without utilizing lumped element capacitors. Self-resonance conditions have been computed by a hybrid FEM-MoM technique. Preliminary results reported here indicate robust mechanical stability, reduced eddy currents heating and negligible susceptibility effects. The gain in B1 /√{ P } is in agreement with the NMR sensitivity enhancement according to the principle of reciprocity. A sensitivity enhancement larger than 3 has been achieved in a monolithic micro resonator inside a standard 4 mm rotor at 500 MHz. These 2D resonators could offer higher performance micro-detection and ease of use of heterogeneous microscopic substances such as biomedical samples, microscopic specimens and thin film materials.

  14. The MONOLITH prototype

    CERN Document Server

    Ambrosio, M; Bencivenni, G; Candela, A M; Chiarini, A; Chignoli, F; De Deo, M; D'Incecco, M; Gerli, S; Giusti, P; Gómez, F; Gustavino, C; Lindozzi, M; Mannocchi, G; Menghetti, H; Morello, C; Murtas, F; Paoluzzi, G; Pilastrini, R; Redaelli, N G; Santoni, M; Sartorelli, G; Terranova, F; Trinchero, G C

    2000-01-01

    MONOLITH (Massive Observatory for Neutrino Oscillation or LImits on THeir existence) is the project of an experiment to study atmospheric neutrino oscillations with a massive magnetized iron detector. The baseline option is a 34 kt iron detector based on the use of about 50000 m/sup 2/ of the glass Resistive Plate Chambers (glass RPCs) developed at the Laboratori Nazionali del Gran Sasso (LNGS). An 8 ton prototype equipped with 23 m/sup 2/ of glass RPC has been realized and tested at the T7-PS beam at CERN. The energy resolution for pions follows a 68%/ square root (E(GeV))+2% law for orthogonally incident particles, in the energy range between 2 and 10 GeV. The time resolution and the tracking capability of the glass RPC are suitable for the MONOLITH experiment. (7 refs).

  15. Structure Learning in Power Distribution Networks

    Energy Technology Data Exchange (ETDEWEB)

    Deka, Deepjyoti [Univ. of Texas, Austin, TX (United States); Chertkov, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-13

    Traditionally power distribution networks are either not observable or only partially observable. This complicates development and implementation of new smart grid technologies, such as these related to demand response, outage detection and management, and improved load-monitoring. Here, inspired by proliferation of the metering technology, we discuss statistical estimation problems in structurally loopy but operationally radial distribution grids consisting in learning operational layout of the network from measurements, e.g. voltage data, which are either already available or can be made available with a relatively minor investment. Our newly suggested algorithms apply to a wide range of realistic scenarios. The algorithms are also computationally efficient – polynomial in time – which is proven theoretically and illustrated computationally on a number of test cases. The technique developed can be applied to detect line failures in real time as well as to understand the scope of possible adversarial attacks on the grid.

  16. Green Demonstrated Analysis on Structure of Our Electric Power Resource

    Institute of Scientific and Technical Information of China (English)

    YANG Jun-bao; YU Jing; CHEN Jin-jing

    2004-01-01

    According to green view and history data, the demonstrated method is applied to analyze the green rationality on the present structure of thermal, hydraulic and nuclear electric power resource; the green trend of large-scale on thermal power generating unit in our history; the distribution of between water and coal resource with the space structure of electric power installed capacity, and recommending the premise, dominance and direction of building our green electric power structure in the future.

  17. Application of monolithic chromatographic supports in virus research.

    Science.gov (United States)

    Krajacic, Mladen; Ravnikar, Maja; Štrancar, Aleš; Gutiérrez-Aguirre, Ion

    2017-05-12

    Key properties of monolithic chromatographic supports, make them suitable for separation and/or concentration of large biomolecules, especially virus particles and viral genomes. One by one, the studies that have been completed so far, contributed to the knowledge that monolith chromatography has hardly any limitation to be applied in virus research. Viruses of different sizes, possessing icosahedral structure and symmetrical morphology, as well as rod-shaped or filamentous viruses with helical structure, even enveloped ones, all of them could be successfully managed by means of monolith chromatography. Same is true for viral genomes, primarily when being distinct from other nucleic acid forms present in a host cell. This review is exclusively focused on viruses. It describes the application of monolith chromatography to different problematics within the virus research field. The reviewed achievements offer new possibilities and trigger new aspects in virology. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Effect of monomer mixture composition on structure and chromatographic properties of poly(divinylbenzene-co-ethylvinylbenzene-co-2-hydroxyethyl methacrylate) monolithic rod columns for separation of small molecules.

    Science.gov (United States)

    Smirnov, Konstantin N; Dyatchkov, Ivan A; Telnov, Maxim V; Pirogov, Andrey V; Shpigun, Oleg A

    2011-07-29

    Porous poly(divinylbenzene-co-ethylvinylbenzene-co-2-hydroxyethyl methacrylate) monoliths were synthesized via thermally initiated free-radical polymerization in confines of surface-vinylized glass columns (150 mm × 3 mm i.d.) and applied to the reversed-phase separation of low-molecular-weight aromatic compounds. In order to compensate for the polymer shrinkage during the synthesis and prevent the monolith from detachment from the column wall, polymerization was conducted under nitrogen pressure. The reaction proceeded at 60°C for 22 h. 2,2'-Azo-bis-isobutironitrile was used as the initiator and 1-dodecanol was used as the porogen. A series of monoliths with different monomer ratios were obtained. All the monoliths had high specific surface areas ranging from 370 to 490 m(2)/g. In the studied range of monomer mixture compositions, the mechanical stability of the stationary phase in water/acetonitrile eluents was found to be high enough and practically insensitive to the fraction of 2-hydroxyethyl methacrylate (HEMA). Increasing the molar fraction of HEMA from 10.5% to 14.7% resulted in the decrease of column permeability by two orders of magnitude (from 1.1×10(-12) to 1.8×10(-14) m(2)) and led to weaker retention of alkylbenzenes. The higher HEMA content was shown to reduce the plate height of the columns in the separation of small molecules from 160-490 μm to 40-76 μm. This was attributed mainly to the decrease of the domain size of the monoliths leading to lower eddy dispersion and mass transfer resistance in the column.

  19. Monolithically Integrated Ge-on-Si Active Photonics

    Directory of Open Access Journals (Sweden)

    Jifeng Liu

    2014-07-01

    Full Text Available Monolithically integrated, active photonic devices on Si are key components in Si-based large-scale electronic-photonic integration for future generations of high-performance, low-power computation and communication systems. Ge has become an interesting candidate for active photonic devices in Si photonics due to its pseudo-direct gap behavior and compatibility with Si complementary metal oxide semiconductor (CMOS processing. In this paper, we present a review of the recent progress in Ge-on-Si active photonics materials and devices for photon detection, modulation, and generation. We first discuss the band engineering of Ge using tensile strain, n-type doping, Sn alloying, and separate confinement of Γ vs. L electrons in quantum well (QW structures to transform the material towards a direct band gap semiconductor for enhancing optoelectronic properties. We then give a brief overview of epitaxial Ge-on-Si materials growth, followed by a summary of recent investigations towards low-temperature, direct growth of high crystallinity Ge and GeSn alloys on dielectric layers for 3D photonic integration. Finally, we review the most recent studies on waveguide-integrated Ge-on-Si photodetectors (PDs, electroabsorption modulators (EAMs, and laser diodes (LDs, and suggest possible future research directions for large-scale monolithic electronic-photonic integrated circuits on a Si platform.

  20. CMOS integrated switching power converters

    CERN Document Server

    Villar-Pique, Gerard

    2011-01-01

    This book describes the structured design and optimization of efficient, energy processing integrated circuits. The approach is multidisciplinary, covering the monolithic integration of IC design techniques, power electronics and control theory. In particular, this book enables readers to conceive, synthesize, design and implement integrated circuits with high-density high-efficiency on-chip switching power regulators. Topics covered encompass the structured design of the on-chip power supply, efficiency optimization, IC-compatible power inductors and capacitors, power MOSFET switches and effi

  1. A monolithic integrated photonic microwave filter

    Science.gov (United States)

    Fandiño, Javier S.; Muñoz, Pascual; Doménech, David; Capmany, José

    2016-12-01

    Meeting the increasing demand for capacity in wireless networks requires the harnessing of higher regions in the radiofrequency spectrum, reducing cell size, as well as more compact, agile and power-efficient base stations that are capable of smoothly interfacing the radio and fibre segments. Fully functional microwave photonic chips are promising candidates in attempts to meet these goals. In recent years, many integrated microwave photonic chips have been reported in different technologies. To the best of our knowledge, none has monolithically integrated all the main active and passive optoelectronic components. Here, we report the first demonstration of a tunable microwave photonics filter that is monolithically integrated into an indium phosphide chip. The reconfigurable radiofrequency photonic filter includes all the necessary elements (for example, lasers, modulators and photodetectors), and its response can be tuned by means of control electric currents. This is an important step in demonstrating the feasibility of integrated and programmable microwave photonic processors.

  2. Structural vulnerability assessment of electric power grids

    NARCIS (Netherlands)

    Koç, Y.; Warnier, M.; Kooij, R.E.; Brazier, F.

    2014-01-01

    Cascading failures are the typical reasons of blackouts in power grids. The grid topology plays an important role in determining the dynamics of cascading failures in power grids. Measures for vulnerability analysis are crucial to assure a higher level of robustness of power grids. Metrics from Comp

  3. Study about the Competing Channel Structure under Bargaining Power

    Institute of Scientific and Technical Information of China (English)

    AI Xing-zheng; ZHANG Chi

    2005-01-01

    From the bargaining process, competing channel structure models are presented. The evolving process of channel structure under different bargaining power is analyzed. The important role of different bargaining power is discussed and the equilibrium result is found. Also the theoretical evidences for competing channel structure choice are given.

  4. Plant oil-based shape memory polymer using acrylic monolith

    Directory of Open Access Journals (Sweden)

    T. Tsujimoto

    2015-09-01

    Full Text Available This article deals with the synthesis of a plant oil-based material using acrylic monolith. An acrylic monolith bearing oxirane groups was prepared via simple technique that involved the dissolution of poly(glycidyl methacrylate-comethyl methacrylate (PGMA in ethanolic – aqueous solution by heating and subsequent cooling. The PGMA monolith had topologically porous structure, which was attributed to the phase separation of the polymer solution. The PGMA monolith was impregnated by epoxidized soybean oil (ESO containing thermally-latent catalyst, and the subsequent curing produced a crosslinked material with relatively good transparency. The Young’s modulus and the tensile strength of polyESO/PGMA increased compared with the ESO homopolymer. The strain at break of polyESO/PGMA was larger than that of the ESO homopolymer and crosslinked PGMA. Furthermore, polyESO/PGMA exhibited good shape memory-recovery behavior.

  5. W-band monolithic oscillator using InAlAs/InGaAs HEMT

    Science.gov (United States)

    Kwon, Y.; Pavlidis, D.; Tutt, M.; Ng, G. I.; Lai, R.

    1990-01-01

    A W-band monolithic integrated oscillator circuit was designed and fabricated using submicron HEMT technology. The oscillation frequency was around 81 GHz and the power was -7 dBm at the chip level. This is the first report of an InAlAs/InGaAs monolithic oscillator operating at the W-band.

  6. Monolithic interconnected modules (MIMs) for thermophotovoltaic energy conversion

    Science.gov (United States)

    Wilt, David; Wehrer, Rebecca; Palmisiano, Marc; Wanlass, Mark; Murray, Christopher

    2003-05-01

    Monolithic interconnected modules (MIMs) are under development for thermophotovoltaic (TPV) energy conversion applications. MIM devices are typified by series-interconnected photovoltaic cells on a common, semi-insulating substrate and generally include rear-surface infrared (IR) reflectors. The MIM architecture is being implemented in InGaAsSb materials without semi-insulating substrates through the development of alternative isolation methodologies. Motivations for developing the MIM structure include: reduced resistive losses, higher output power density than for systems utilizing front surface spectral control, improved thermal coupling and ultimately higher system efficiency. Numerous design and material changes have been investigated since the introduction of the MIM concept in 1994. These developments as well as the current design strategies are addressed.

  7. Reconfigurable optical switches with monolithic electrical-to-optical interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J.; Zhou, P. [New Mexico Univ., Albuquerque, NM (United States). Center for High Technology Materials; Zolper, J.C.; Lear, K.L.; Vawter, G.A. [Sandia National Labs., Albuquerque, NM (United States); Leibenguth, R.E.; Adams, A.C. [AT and T Bell Labs., Breinigsville, PA (United States)

    1994-03-01

    Vertical cavity surface-emitting lasers (VCSELs) can be integrated with heterojunction phototransistors (HPTs) and heterojunction bipolar transistors (HBTs) on the same wafer to form high speed optical and optoelectronic switches, respectively, that can be optically or electrically addressed. This permits the direct communication and transmission of data between distributed electronic processors through an optical switching network. The experimental demonstration of an integrated optoelectronic HBT/VCSEL switch combining a GaAs/AlGaAs heterojunction bipolar transistor (HBT) with a VCSEL is described below, using the same epilayer structure upon which binary HPT/VCSEL optical switches are also built. The monolithic HBT/VCSEL switch has high current gain, low power dissipation, and a high optical to electrical conversion efficiency. Its modulation has been measured and modeled.

  8. Monolithic single mode interband cascade lasers with wide wavelength tunability

    Science.gov (United States)

    von Edlinger, M.; Weih, R.; Scheuermann, J.; Nähle, L.; Fischer, M.; Koeth, J.; Kamp, M.; Höfling, S.

    2016-11-01

    Monolithic two-section interband cascade lasers offering a wide wavelength tunability in the wavelength range around 3.7 μm are presented. Stable single mode emission in several wavelength channels was realized using the concept of binary superimposed gratings and two-segment Vernier-tuning. The wavelength selective elements in the two segments were based on specially designed lateral metal grating structures defined by electron beam lithography. A dual-step dry etch process provided electrical separation between the segments. Individual current control of the segments allowed wavelength channel selection as well as continuous wavelength tuning within channels. A discontinuous tuning range extending over 158 nm in up to six discrete wavelength channels was achieved. Mode hop free wavelength tuning up to 14 nm was observed within one channel. The devices can be operated in continuous wave mode up to 30 °C with the output powers of 3.5 mW around room temperature.

  9. Porous polymer monolithic col

    Directory of Open Access Journals (Sweden)

    Lydia Terborg

    2015-05-01

    Full Text Available A new approach has been developed for the preparation of mixed-mode stationary phases to separate proteins. The pore surface of monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate capillary columns was functionalized with thiols and coated with gold nanoparticles. The final mixed mode surface chemistry was formed by attaching, in a single step, alkanethiols, mercaptoalkanoic acids, and their mixtures on the free surface of attached gold nanoparticles. Use of these mixtures allowed fine tuning of the hydrophobic/hydrophilic balance. The amount of attached gold nanoparticles according to thermal gravimetric analysis was 44.8 wt.%. This value together with results of frontal elution enabled calculation of surface coverage with the alkanethiol and mercaptoalkanoic acid ligands. Interestingly, alkanethiols coverage in a range of 4.46–4.51 molecules/nm2 significantly exceeded that of mercaptoalkanoic acids with 2.39–2.45 molecules/nm2. The mixed mode character of these monolithic stationary phases was for the first time demonstrated in the separations of proteins that could be achieved in the same column using gradient elution conditions typical of reverse phase (using gradient of acetonitrile in water and ion exchange chromatographic modes (applying gradient of salt in water, respectively.

  10. Synthesis of silver nanoparticles confined in hierarchically porous monolithic silica: a new function in aromatic hydrocarbon separations.

    Science.gov (United States)

    Zhu, Yang; Morisato, Kei; Li, Wenyan; Kanamori, Kazuyoshi; Nakanishi, Kazuki

    2013-03-01

    Silver nanoparticles (Ag NPs) have been homogeneously introduced into hierarchically porous monolithic silica columns with well-defined macropores and SBA-15-type hexagonally ordered mesopores by using ethanol as the mild reductant. Within the cylindrical silica mesopores treated with aminopropyl groups as the host, monocrystalline Ag NPs and nanorods are obtained after being treated in silver nitrate/ethanol solution at room temperature for different durations of reducing time. The loading of Ag NPs in the monolith can be increased to 33 wt % by the repetitive treatment, which also led to the formation of polycrystalline Ag nanorods in the mesopores. Although the bare silica column cannot separate aromatic hydrocarbons, good separation of those molecules by noncharged Ag NPs confined in the porous structure of the monolith has been for the first time demonstrated with the Ag NP-embedded silica column. The NP-embedded monolithic silica would be a powerful separation tool for hydrocarbons with different number, position, and configuration of unsaturated bonds.

  11. Monolitni katalizatori i reaktori: osnovne značajke, priprava i primjena (Monolith catalysts and reactors: preparation and applications

    Directory of Open Access Journals (Sweden)

    Tomašić, V.

    2004-12-01

    Full Text Available Monolithic (honeycomb catalysts are continuous unitary structures containing many narrow, parallel and usually straight channels (or passages. Catalytically active components are dispersed uniformly over the whole porous ceramic monolith structure (so-called incorporated monolithic catalysts or are in a layer of porous material that is deposited on the walls of channels in the monolith's structure (washcoated monolithic catalysts. The material of the main monolithic construction is not limited to ceramics but includes metals, as well. Monolithic catalysts are commonly used in gas phase catalytic processes, such as treatment of automotive exhaust gases, selective catalytic reduction of nitrogen oxides, catalytic removal of volatile organic compounds from industrial processes, etc. Monoliths continue to be the preferred support for environmental applications due to their high geometric surface area, different design options, low pressure drop, high temperature durability, mechanical strength, ease of orientation in a reactor and effectiveness as a support for a catalytic washcoat. As known, monolithic catalysts belong to the class of the structured catalysts and/or reactors (in some cases the distinction between "catalyst" and "reactor" has vanished. Structured catalysts can greatly intensify chemical processes, resulting in smaller, safer, cleaner and more energy efficient technologies. Monolith reactors can be considered as multifunctional reactors, in which chemical conversion is advantageously integrated with another unit operation, such as separation, heat exchange, a secondary reaction, etc. Finally, structured catalysts and/or reactors appear to be one of the most significant and promising developments in the field of heterogeneous catalysis and chemical engineering of the recent years. This paper gives a description of the background and perspectives for application and development of monolithic materials. Different methods and techniques

  12. Monolithic series-connected gallium arsenide converter development

    Energy Technology Data Exchange (ETDEWEB)

    Spitzer, M.B.; McClelland, R.W.; Dingle, B.D.; Dingle, J.E.; Hill, D.S. (Kopin Corp., Taunton, MA (United States)); Rose, B.H. (Sandia National Labs., Albuquerque, NM (United States))

    1991-01-01

    We report the development of monolithic GaAs photovoltaic devices intended to convert light generated by a laser or other bright source to electricity. The converters described here can provide higher operating voltage than is possible using a single-junction converter, owing to use of a monolithic circuit that forms a planar series-connected string of single-junction sub-cells. This planar monolithic circuit is arranged to deliver the desired voltage and current during operation at the maximum power point. The paper describes two-, six-, and twelve-junction converters intended for illumination by a laser diode with a wavelength of 0.8 {mu}m. Design and characterization data are presented for optical power in the range of 100 mW to 1 W. The best conversion efficiency exceeds 50%. 9 refs., 4 figs., 2 tabs.

  13. Steam reforming of n-hexane on pellet and monolithic catalyst beds. A comparative study on improvements due to heat transfer

    Science.gov (United States)

    1981-01-01

    Monolithic catalysts with higher available active surface areas and better thermal conductivity than conventional pellets beds, making possible the steam reforming of fuels heavier than naphtha, were examined. Performance comparisons were made between conventional pellet beds and honeycomb monolith catalysts using n-hexane as the fuel. Metal-supported monoliths were examined. These offer higher structural stability and higher thermal conductivity than ceramic supports. Data from two metal monoliths of different nickel catalyst loadings were compared to pellets under the same operating conditions. Improved heat transfer and better conversion efficiencies were obtained with the monolith having higher catalyst loading. Surface-gas interaction was observed throughout the length of the monoliths.

  14. Market power versus capital structure determinants: Do they impact leverage?

    Directory of Open Access Journals (Sweden)

    Agha Jahanzeb

    2015-12-01

    Full Text Available The purpose of this study is to investigate the association between market power and capital structure. This study will further provide a logical explanation towards the factors affecting capital structure. This study analysed 176 non-financial Pakistani companies listed on Karachi Stock Exchange over the period of 2003–2012. Capital structure has been tried to investigate with a different perspective by investigating its association with market power. It has been seen that there is a significant and positive relation between market power and capital structure. Size and liquidity remained significantly negative with capital structure, whereas profitability and dividend payout remained significantly positive with capital structure. To the best of authors’ knowledge, this is the first study that investigates the relationship between market power and capital structure in any developing economy by employing the data of non-financial Pakistani firms.

  15. Measurement and Modeling of the Transfer Function of a Monolithic SOA-EA 2R-Regenerator

    DEFF Research Database (Denmark)

    Christiansen, Lotte Jin; Öhman, Filip; Kjær, Rasmus

    2005-01-01

    We have measured steep power transfer characteristics with tunable threshold for a monolithic 2R-regenerator combining amplifying and absorbing sections. Modeling results explain the basic characteristics.......We have measured steep power transfer characteristics with tunable threshold for a monolithic 2R-regenerator combining amplifying and absorbing sections. Modeling results explain the basic characteristics....

  16. Monolithically integrated Ge CMOS laser

    Science.gov (United States)

    Camacho-Aguilera, Rodolfo

    2014-02-01

    Ge-on-Si devices are explored for photonic integration. Through the development of better growth techniques, monolithic integration, laser design and prototypes, it was possible to probe Ge light emitters with emphasis on lasers. Preliminary worked shows thermal photonic behavior capable of enhancing lamination at high temperatures. Increase luminescence is observed up to 120°C from L-band contribution. Higher temperatures show contribution from Δ -band. The increase carrier thermal contribution suggests high temperature applications for Ge light emitters. A Ge electrically pumped laser was probed under 0.2% biaxial strain and doping concentration ~4.5×1019cm-3 n-type. Ge pnn lasers exhibit a gain >1000cm-1 with 8mW power output, presenting a spectrum range of over 200nm, making Ge the ideal candidate for Si photonics. Large temperatures fluctuations and process limit the present device. Theoretically a gain of >4000cm- gain is possible with a threshold of as low as 1kA/cm2. Improvements in Ge work

  17. Effect of plastic deformation on the structure and mechanical properties of an ultra-low carbon interstitial-free steel in the monolithic material and as a component of a sandwich composite

    Science.gov (United States)

    Gladkovsky, S. V.; Kuteneva, S. V.; Kamantsev, I. S.; Sergeev, S. N.; Safarov, I. M.

    2016-10-01

    The structure and mechanical properties of ultra-low carbon interstitial-free (IF) steel in the annealed state, after warm and cold rolling, and as a component of seven-layer steel-aluminum composite have been studied. A comparative analysis of the results of structural studies using optical microscopy and scanning and transmission electron microscopy have revealed the possibility of the formation of an ultrafinegrained structure in a steel layer during rolling at temperatures ranging from room temperature to 520°C. It has been found that the seven-layer composite has higher strength properties as compared to monolithic samples of the IF steel after analogous regime of the warm rolling.

  18. Synthesis of ZSM-5 Monoliths with Hierarchical Porosity

    Institute of Scientific and Technical Information of China (English)

    Tong Yangchuan; Zhao Tianbo; Li Fengyan; Zong Baoning; Wang Yue

    2006-01-01

    A new route to synthesize ZSM-5 monoliths with hierarchical pore structure has been referred to in this stud y. The successful incorporation of the macropores and mesopores within the ZSM-5 structure was achieved through transforming the skeleton of the macroporous silica gel into zeolite ZSM-5 using carbon materials as the transitional template. The ZSM-5 crystal covered part of the macroporous material, and provided micropores to the macroporous silica gel. The structure of carbon monolith was studied after dissolving the silica contained in the carbon/silica composite.

  19. FLUIDIZED BED STEAM REFORMER MONOLITH FORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C

    2006-12-22

    Fluidized Bed Steam Reforming (FBSR) is being considered as an alternative technology for the immobilization of a wide variety of aqueous high sodium containing radioactive wastes at various DOE facilities in the United States. The addition of clay, charcoal, and a catalyst as co-reactants converts aqueous Low Activity Wastes (LAW) to a granular or ''mineralized'' waste form while converting organic components to CO{sub 2} and steam, and nitrate/nitrite components, if any, to N{sub 2}. The waste form produced is a multiphase mineral assemblage of Na-Al-Si (NAS) feldspathoid minerals with cage-like structures that atomically bond radionuclides like Tc-99 and anions such as SO{sub 4}, I, F, and Cl. The granular product has been shown to be as durable as LAW glass. Shallow land burial requires that the mineralized waste form be able to sustain the weight of soil overburden and potential intrusion by future generations. The strength requirement necessitates binding the granular product into a monolith. FBSR mineral products were formulated into a variety of monoliths including various cements, Ceramicrete, and hydroceramics. All but one of the nine monoliths tested met the <2g/m{sup 2} durability specification for Na and Re (simulant for Tc-99) when tested using the Product Consistency Test (PCT; ASTM C1285). Of the nine monoliths tested the cements produced with 80-87 wt% FBSR product, the Ceramicrete, and the hydroceramic produced with 83.3 wt% FBSR product, met the compressive strength and durability requirements for an LAW waste form.

  20. Monolithic supports with unique geometries and enhanced mass transfer.

    Energy Technology Data Exchange (ETDEWEB)

    Stuecker, John Nicholas; Ferrizz, Robert Matthew; Cesarano, Joseph, III; Miller, James Edward

    2004-01-01

    The catalytic combustion of natural gas has been the topic of much research over the past decade. Interest in this technology results from a desire to decrease or eliminate the emissions of harmful nitrogen oxides (NOX) from gas turbine power plants. A low-pressure drop catalyst support, such as a ceramic monolith, is ideal for this high-temperature, high-flow application. A drawback to the traditional honeycomb monoliths under these operating conditions is poor mass transfer to the catalyst surface in the straight-through channels. 'Robocasting' is a unique process developed at Sandia National Laboratories that can be used to manufacture ceramic monoliths with alternative 3-dimensional geometries, providing tortuous pathways to increase mass transfer while maintaining low pressure drops. This report details the mass transfer effects for novel 3-dimensional robocast monoliths, traditional honeycomb-type monoliths, and ceramic foams. The mass transfer limit is experimentally determined using the probe reaction of CO oxidation over a Pt / {gamma}-Al{sub 2}O{sub 3} catalyst, and the pressure drop is measured for each monolith sample. Conversion versus temperature data is analyzed quantitatively using well-known dimensionless mass transfer parameters. The results show that, relative to the honeycomb monolith support, considerable improvement in mass transfer efficiency is observed for robocast samples synthesized using an FCC-like geometry of alternating rods. Also, there is clearly a trade-off between enhanced mass transfer and increased pressure drop, which can be optimized depending on the particular demands of a given application.

  1. Survey on the consciousness structure toward nuclear power generation

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, M.; Yoshida, T. (Nomura Research Institute, Kamakura, Kanagawa (Japan))

    1981-05-01

    A survey on the popular consciousness toward nuclear power generation was carried out by direct means of questionnaire to 1600 persons, ages from 20 to 69, in power demand areas (Tokyo and Osaka) and power supply areas (sites of nuclear power generation) from early February to early March, 1980, and the recovery rate was 74.4% (1190 persons). The results are described by way of their explanation. The purpose is to clarify the structure of popular consciousness toward nuclear energy, in particular nuclear power generation, and the nature of its acceptance. That is, it was surveyed how general people in the power supply and the power demand areas are taking nuclear power generation concerning its need and safety, and further how the attitudes are constituted and vary.

  2. Light weight, high-speed, and self-powered wireless fiber optic sensor (WiFOS) structural health monitor system for avionics and aerospace environments

    Science.gov (United States)

    Mendoza, Edgar A.; Kempen, Cornelia; Sun, Sunjian; Esterkin, Yan

    2014-09-01

    This paper describes recent progress towards the development of an innovative light weight, high-speed, and selfpowered wireless fiber optic sensor (WiFOS™) structural health monitor system suitable for the onboard and in-flight unattended detection, localization, and classification of load, fatigue, and structural damage in advanced composite materials commonly used in avionics and aerospace systems. The WiFOS™ system is based on ROI's advancements on monolithic photonic integrated circuit microchip technology, integrated with smart power management, on-board data processing, wireless data transmission optoelectronics, and self-power using energy harvesting tools such as solar, vibration, thermoelectric, and magneto-electric. The self-powered, wireless WiFOS™ system offers a versatile and powerful SHM tool to enhance the reliability and safety of avionics platforms, jet fighters, helicopters, commercial aircraft that use lightweight composite material structures, by providing comprehensive information about the structural integrity of the structure from a large number of locations. Immediate SHM applications are found in rotorcraft and aircraft, ships, submarines, and in next generation weapon systems, and in commercial oil and petrochemical, aerospace industries, civil structures, power utilities, portable medical devices, and biotechnology, homeland security and a wide spectrum of other applications.

  3. A Monolithic Oxide-Based Transversal Thermoelectric Energy Harvester

    Science.gov (United States)

    Teichert, S.; Bochmann, A.; Reimann, T.; Schulz, T.; Dreßler, C.; Udich, S.; Töpfer, J.

    2016-03-01

    We report the fabrication and properties of a monolithic transversal thermoelectric energy harvester based on the combination of a thermoelectric oxide and a metal. The fabrication of the device is done with a ceramic multilayer technology using printing and co-firing processes. Five transversal devices were combined to a meander-like thermoelectric generator. Electrical measurements and finite element calculations were performed to characterize the resulting thermoelectric generator. A maximum experimental electrical power output of 30.2 mW at a temperature difference of {Δ }T = 208 K was found. The prepared monolithic thermoelectric generator provides at {Δ }T = 35 K sufficient energy to drive a simple electronic sensor application.

  4. Structural integrity of Offshore Wind Power Substructures

    OpenAIRE

    Imafidon, Oliver Osazee

    2010-01-01

    Offshore wind turbine structures are now being developed in relatively deep waters with the purpose of capturing and utilizing the strong winds at sea. The structures must be robust in order to resist extreme loads. To be competitive, a cost reduction in fabrication and installation of wind substructures is necessary and the use of high strength steel has been suggested as one way of achieving this through the design of light-weight structures.The thesis gives an overview of offshore wind tur...

  5. Comparison of perfusion media and monoliths for protein and virus-like particle chromatography.

    Science.gov (United States)

    Wu, Yige; Abraham, Dicky; Carta, Giorgio

    2016-05-20

    Structural and performance characteristics of perfusion chromatography media (POROS HS 20 and 50) and those of a polymethacrylate monolith (CIM SO3-1 tube monolith column) are compared for protein and virus-like particle chromatography using 1mL columns. Axial flow columns are used for POROS while the monolith has a radial flow configuration, which provides comparable operating pressures. The POROS beads contain a bimodal distribution of pore sizes, some as large as 0.5μm, which allow a small fraction of the mobile phase to flow within the particles, while the monolith contains 1-2μm flow channels. For proteins (lysozyme and IgG), the dynamic binding capacity of the POROS columns is more than twice that of the monolith at longer residence times. While the DBC of the POROS HS 50 column decreases at shorter residence times, the DBC of the POROS HS 20 column for IgG remains nearly twice that of the monolith at residence times at least as low as 0.2min as a result of intraparticle convection. Protein recoveries are comparable for all three columns. For VLPs, however, the eluted peaks are broader and recovery is lower for the monolith than for the POROS columns and is dependent on the direction of flow in the monolith, which is attributed to denser layer observed by SEM at the inlet surface of the monolith that appears to trap VLPs when loading in the normal flow direction.

  6. Self powered system for civil structures

    Science.gov (United States)

    Shoureshi, Rahmat A.

    2009-03-01

    Globally, civil infrastructures are deteriorating at an alarming rate caused by overuse, overloading, aging, damage or failure due to natural or man-made hazards. With such a vast network of deteriorating infrastructure, there is a growing interest in continuous monitoring technologies. In order to provide a true distributed sensor and control system for civil structures, we are developing a Structural Nervous System that mimics key attributes of a human nervous system. This nervous system is made up of building blocks that are designed based on mechanoreceptors as a fundamentally new approach for the development of a structural health monitoring and diagnostic system that utilizes the recently developed piezo-fibers capable of sensing and actuation. In particular, our research has been focused on producing a sensory nervous system for civil structures by using piezo-fibers as sensory receptors, nerve fibers, neuronal pools, and spinocervical tract to the nodal and central processing units. This paper presents up to date results of our research, including the design and analysis of the structural nervous system.

  7. New Graphene Form of Nanoporous Monolith for Excellent Energy Storage.

    Science.gov (United States)

    Bi, Hui; Lin, Tianquan; Xu, Feng; Tang, Yufeng; Liu, Zhanqiang; Huang, Fuqiang

    2016-01-13

    Extraordinary tubular graphene cellular material of a tetrahedrally connected covalent structure was very recently discovered as a new supermaterial with ultralight, ultrastiff, superelastic, and excellent conductive characteristics, but no high specific surface area will keep it from any next-generation energy storage applications. Herein, we prepare another new graphene monolith of mesoporous graphene-filled tubes instead of hollow tubes in the reported cellular structure. This graphene nanoporous monolith is also composed of covalently bonded carbon network possessing high specific surface area of ∼1590 m(2) g(-1) and electrical conductivity of ∼32 S cm(-1), superior to graphene aerogels and porous graphene forms self-assembled by graphene oxide. This 3D graphene monolith can support over 10 000 times its own weight, significantly superior to CNT and graphene cellular materials with a similar density. Furthermore, pseudocapacitance-active functional groups are introduced into the new nanoporous graphene monolith as an electrode material in electrochemical capacitors. Surprisingly, the electrode of 3D mesoporous graphene has a specific capacitance of 303 F g(-1) and maintains over 98% retention after 10 000 cycles, belonging to the list for the best carbon-based active materials. The macroscopic mesoporous graphene monolith suggests the great potential as an electrode for supercapacitors in energy storage areas.

  8. Geographic Spillovers, Structural Power and Growing 'Agency' Post Lisbon

    DEFF Research Database (Denmark)

    Zank, Wolfgang

    2012-01-01

    The "actorness" of the European Union in external relations is still, also after the Lisbon Treaty, only partially developed. However, the EU has built up a considerable Structural Power towards its suroundings, mainly due to its big Internal Market. a Power of attraction and geographical...

  9. Reliable and More Powerful Methods for Power Analysis in Structural Equation Modeling

    Science.gov (United States)

    Yuan, Ke-Hai; Zhang, Zhiyong; Zhao, Yanyun

    2017-01-01

    The normal-distribution-based likelihood ratio statistic T[subscript ml] = nF[subscript ml] is widely used for power analysis in structural Equation modeling (SEM). In such an analysis, power and sample size are computed by assuming that T[subscript ml] follows a central chi-square distribution under H[subscript 0] and a noncentral chi-square…

  10. Recent advances in the preparation and application of monolithic capillary columns in separation science

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tingting; Yang, Xi; Xu, Yujing [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing, 210009 (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Nanjing, 210009 (China); Ji, Yibing, E-mail: jiyibing@msn.com [Department of Analytical Chemistry, China Pharmaceutical University, Nanjing, 210009 (China); Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, Nanjing, 210009 (China)

    2016-08-10

    Novel column technologies involving various materials and efficient reactions have been investigated for the fabrication of monolithic capillary columns in the field of analytical chemistry. In addition to the development of these miniaturized systems, a variety of microscale separation applications have achieved noteworthy results, providing a stepping stone for new types of chromatographic columns with improved efficiency and selectivity. Three novel strategies for the preparation of capillary monoliths, including ionic liquid-based approaches, nanoparticle-based approaches and “click chemistry”, are highlighted in this review. Furthermore, we present the employment of state-of-the-art capillary monolithic stationary phases for enantioseparation, solid-phase microextraction, mixed-mode separation and immobilized enzyme reactors. The review concludes with recommendations for future studies and improvements in this field of research. - Highlights: • Preparation of novel monolithic capillary columns have shown powerful potential in analytical chemistry field. • Various materials including ionic liquids and nanoparticles involved into capillary monolithic micro-devices are concluded. • Click chemistry strategy applied for preparing monolithic capillary columns is reviewed. • Recent strategies utilized in constructing different capillary monoliths for enantiomeric separation are summarized. • Advancement of capillary monoliths for complex samples analysis is comprehensively described.

  11. Synthesis and methane storage of binder-free porous graphene monoliths

    Institute of Scientific and Technical Information of China (English)

    Guoqing Ning; Hao Wang; Xiaoxin Zhang; Chenggen Xu; Guangjin Chen; Jinsen Gao

    2013-01-01

    Nanomesh graphene (NMG) obtained by template chemical vapor deposition was used to synthesize the binder-free graphene monoliths by simple tablet pressing.The stacking manner of the NMG sheets was crucial to the cohesion interaction between the graphene sheets,only the NMG materials with a loosely stacking manner could be pressed into binder-free monoliths.At the tableting pressure of 2-8 MPa,both the bulk densities and the specific surface areas of the monoliths keep nearly constant as the tableting pressure increases,indicating that the NMG monoliths have obvious elasticity and a porous structure due to the large corrugations and the mesh structures of the graphene sheets.As a result,an extraordinary methane storage capacity of 236 (v/v) at 9MPa was obtained in the graphene monolith prepared by tableting at 4 MPa.

  12. Variable structure control for maximum wind power extraction

    Energy Technology Data Exchange (ETDEWEB)

    Barambones, O.; Gonzalez de Durana, J.M.; Alcorta, P. [Univ. of the Basque Country, Vitoria (Spain)

    2009-07-01

    The future development of wind power technology will affect the level of impact that wind power will have on the power system. Very large wind farms can pose complex technical challenges while also paving the way for other new technologies that will help with electric grid integration. Increasingly complicated power electronic and computerized control schemes will lead to significant improvements and full controllability of available wind power. Reactive power compensation is an important issue in the control of distribution and transmission systems as it increases feeder system losses, reduces system power factor, and can cause large-amplitude variations in load-side voltage. Moreover, rapid changes in the reactive power consumption of large load centers can cause voltage amplitude oscillations, leading to a change in the electric system real power demand resulting in power oscillation. This paper described a sliding mode vector control for a double fed induction generator (DFIG) drive, used in variable speed wind power generation. The study proposed a new variable structure control which has an integral sliding surface to relax the requirement of the acceleration signal, commonly used in conventional sliding mode speed control techniques. The paper discussed the system modelling, DFIG control scheme, and simulation results. A test of the proposed method based on a two-bladed horizontal axis wind turbine was conducted using the Matlab/Simulink software. In this test, several operating conditions were simulated and the study concluded that satisfactory results were obtained. 14 refs., 5 figs.

  13. Report on aging of nuclear power plant reinforced concrete structures

    Energy Technology Data Exchange (ETDEWEB)

    Naus, D.J.; Oland, C.B. [Oak Ridge National Lab., TN (United States); Ellingwood, B.R. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

    1996-03-01

    The Structural Aging Program provides the US Nuclear Regulatory Commission with potential structural safety issues and acceptance criteria for use in continued service assessments of nuclear power plant safety-related concrete structures. The program was organized under four task areas: Program Management, Materials Property Data Base, Structural Component Assessment/Repair Technology, and Quantitative Methodology for Continued Service Determinations. Under these tasks, over 90 papers and reports were prepared addressing pertinent aspects associated with aging management of nuclear power plant reinforced concrete structures. Contained in this report is a summary of program results in the form of information related to longevity of nuclear power plant reinforced concrete structures, a Structural Materials Information Center presenting data and information on the time variation of concrete materials under the influence of environmental stressors and aging factors, in-service inspection and condition assessments techniques, repair materials and methods, evaluation of nuclear power plant reinforced concrete structures, and a reliability-based methodology for current and future condition assessments. Recommendations for future activities are also provided. 308 refs., 61 figs., 50 tabs.

  14. Monolithic thermally bonded Er3+, Yb3+:glass/Co2+:MgAl2O4 microchip lasers

    Science.gov (United States)

    Mlynczak, Jaroslaw; Belghachem, Nabil

    2015-12-01

    The highest ever reported 10 kW peak power in monolithic thermally bonded Er3+, Yb3+:glass/Co2+:MgAl2O4 microchip laser was achieved. To show the superiority of monolithic microchip lasers over those with external mirrors the laser generation characteristics of the same samples in both cases were compared.

  15. Preparation of a biomimetic polyphosphorylcholine monolithic column for immobilized artificial membrane chromatography.

    Science.gov (United States)

    Zhao, XiangLong; Chen, WeiJia; Zhou, ZhengYin; Wang, QiQin; Liu, ZhengHua; Moaddel, Ruin; Jiang, ZhengJin

    2015-08-14

    The present work aims to prepare a novel phosphatidylcholine functionalized monolithic stationary phase by in situ co-polymerization of 12-methacryloyl dodecylphosphocholine (MDPC) and ethylene dimethacrylate (EDMA) for immobilized artificial membrane chromatography. Scanning electron microscopy, energy dispersive X-ray spectroscopy, FT-IR spectroscopy, pore size distribution analysis, ζ-potential analysis and micro-HPLC were used to evaluate the monolithic structure and physicochemical properties. Satisfactory morphology, high mechanical stability, good permeability and chromatographic performance were obtained on the optimized monolithic columns. A typical reverse-phase retention mechanism was observed over a wide range of organic solvent content (acetonitrilecolumn (IAM.PC.DD2) and poly(MDPC-co-EDMA) monolith. This novel poly(MDPC-co-EDMA) monolith exhibited good potential for studying the drug-membrane interaction.

  16. Structures and construction of nuclear power plants on lunar surface

    Science.gov (United States)

    Shimizu, Katsunori; Kobatake, Masuhiko; Ogawa, Sachio; Kanamori, Hiroshi; Okada, Yasuhiko; Mano, Hideyuki; Takagi, Kenji

    1991-07-01

    The best structure and construction techniques of nuclear power plants in the severe environments on the lunar surface are studied. Facility construction types (functional conditions such as stable structure, shield thickness, maintainability, safety distances, and service life), construction conditions (such as construction methods, construction equipment, number of personnel, time required for construction, external power supply, and required transportation) and construction feasibility (construction method, reactor transportation between the moon and the earth, ground excavation for installation, loading and unloading, transportation, and installation, filling up the ground, electric power supply of plant S (300 kW class) and plant L (3000 kW class)) are outlined. Items to pay attention to in construction are (1) automation and robotization of construction; (2) cost reduction by multi functional robots; and (3) methods of supplying power to robots. A precast concrete block manufacturing plant is also outlined.

  17. Pulse swallowing frequency divider with low power and compact structure

    Institute of Scientific and Technical Information of China (English)

    Gao Haijun; Sun Lingling; Cai Chaobo; Zhan Haiting

    2012-01-01

    A pulse swallowing frequency divider with low power and compact structure is presented.One of the DFFs in the divided by 2/3 prescaler is controlled by the modulus control signal,and automatically powered off when it has no contribution to the operation of the prescaler.The DFFs in the program counter and the swallow counter are shared to compose a compact structure,which reduces the power consumption further.The proposed multi-modulus frequency divider was implemented in a standard 65 nm CMOS process with an area of 28 ×22 μm2.The power consumption of the divider is 0.6 mW under 1.2 V supply voltage when operating at 988 MHz.

  18. In situ Fabrication of Monolithic Copper Azide

    Science.gov (United States)

    Li, Bing; Li, Mingyu; Zeng, Qingxuan; Wu, Xingyu

    2016-04-01

    Fabrication and characterization of monolithic copper azide were performed. The monolithic nanoporous copper (NPC) with interconnected pores and nanoparticles was prepared by decomposition and sintering of the ultrafine copper oxalate. The preferable monolithic NPC can be obtained through decomposition and sintering at 400°C for 30 min. Then, the available monolithic NPC was in situ reacted with the gaseous HN3 for 24 h and the monolithic NPC was transformed into monolithic copper azide. Additionally, the copper particles prepared by electrodeposition were also reacted with the gaseous HN3 under uniform conditions as a comparison. The fabricated monolithic copper azide was characterized by Fourier transform infrared (FTIR), inductively coupled plasma-optical emission spectrometry (ICP-OES), and differential scanning calorimetry (DSC).

  19. Conversion of methanol to gasoline-range hydrocarbons in a ZSM-5 coated monolithic reactor

    Energy Technology Data Exchange (ETDEWEB)

    Antia, J.E.; Govind, R. (Univ. of Cincinnati, OH (United States). Dept. of Chemical Engineering)

    1995-01-01

    Novel reactor configurations featuring catalysts supported on monolithic or honeycomb structures are being increasingly used for a number of applications. In this work, a zeolite-coated monolithic reactor is employed for the conversion of methanol to gasoline-range hydrocarbons. Experimental results show that the conversion and hydrocarbon product distribution compare favorably with data reported for fixed and fluid beds. Mathematical modeling shows that the conversion here is controlled by diffusion in the molecule-sized intracrystalline pores of the zeolite structure. This finding is of considerable important because it demonstrates that monolithic reactors are well-suited to zeolite-based catalytic processes.

  20. Structural Materials and Fuels for Space Power Plants

    Science.gov (United States)

    Bowman, Cheryl; Busby, Jeremy; Porter, Douglas

    2008-01-01

    A fission reactor combined with Stirling convertor power generation is one promising candidate in on-going Fission Surface Power (FSP) studies for future lunar and Martian bases. There are many challenges for designing and qualifying space-rated nuclear power plants. In order to have an affordable and sustainable program, NASA and DOE designers want to build upon the extensive foundation in nuclear fuels and structural materials. This talk will outline the current Fission Surface Power program and outline baseline design options for a lunar power plant with an emphasis on materials challenges. NASA first organized an Affordable Fission Surface Power System Study Team to establish a reference design that could be scrutinized for technical and fiscal feasibility. Previous papers and presentations have discussed this study process in detail. Considerations for the reference design included that no significant nuclear technology, fuels, or material development were required for near term use. The desire was to build upon terrestrial-derived reactor technology including conventional fuels and materials. Here we will present an overview of the reference design, Figure 1, and examine the materials choices. The system definition included analysis and recommendations for power level and life, plant configuration, shielding approach, reactor type, and power conversion type. It is important to note that this is just one concept undergoing refinement. The design team, however, understands that materials selection and improvement must be an integral part of the system development.

  1. Multi-channel monolithic integrated optic fiber Bragg grating sensor interrogator

    Science.gov (United States)

    Mendoza, Edgar A.; Esterkin, Yan; Kempen, Cornelia; Sun, Zongjian

    2011-09-01

    Fiber Bragg grating (FBG) is a mature sensing technology for the measurement of strain, vibration, acoustics, acceleration, pressure, temperature, moisture, and corrosion. It has gained rapid acceptance in civil, aerospace, chemical and petrochemical, medicine, aviation and automotive industries. The most prominent advantages of FBG are: small size and light weight, distributed array of FBG transducers on a single fiber, and immunity to radio frequency interference. However, a major disadvantage of FBG technology is that conventional state-of-the-art FBG interrogation system is typically bulky, heavy, and costly bench top instruments that are typically assembled from off-the-shelf fiber optic and optical components integrated with a signal electronics board into an instrument console. Based on the industrial need for a compact FBG interrogation system, this paper describes recent progress towards the development of miniature fiber Bragg grating sensor interrogator (FBG-Transceiver™) system based on multi-channel monolithic integrated optic sensor microchip technology. The integrated optic microchip technology enables monolithic integration of all functionalities, both passive and active, of conventional bench top FBG sensor interrogator system, packaged in a miniaturized, low power operation, 2 cm×5 cm small form factor (SFF) package suitable for long-term structural health monitoring in applications where size, weight, and power are critical for operation.

  2. A Monolithically Integrated 12V/5V Switch-Capacitor DC-DC Converter

    Institute of Scientific and Technical Information of China (English)

    耿莉; 陈治明; 刘先锋

    2000-01-01

    A monolithically integrated 12V/SV switch capacitor DC-DC converter with structure-simplified main circuit and control circuit is presented. Its topological circuit and basic operating principle are discussed in detail. It is shown that elevated operating frequency, increased capacitance and reduced turn-on voltage of the diodes can make the converter's output characteristics improved. Reducing resistance of the equivalent resistors and other parasitic parameters can make the operation frequency higher. As a feasible efficient method to fabricate monolithically integrated converter with high frequency and high output power, several basic circuits are parallelly combined where the serial-parallel capacitance is optimized for the maximum output power. The device selection and its fabrication method are presented. A feasible integration process and its corresponding layout are designed. All active devices including switching transistors and diodes are integrated together with all passive cells including capacitors and resistor on a single chip based on BiMOS process,as has been verified to be correct and practical by simulation and chip test.

  3. Control of powerful microwaves using EBG plasma structures

    Science.gov (United States)

    Simonchik, Leanid; Callegari, Thierry; Sokoloff, Jerome; Usachonak, Maxim

    2016-09-01

    Glow discharge plasmas have great potential for application as control elements in microwave devices designed on the basis of electromagnetic band gap (EBG) structures. In this report, a plasma control of powerful microwave propagation by means of 1D and 2D EBG structures is under investigation. Three pulsed discharges in argon (or helium) at atmospheric pressure are applied in the capacity of plasma inhomogeneities. Temporal behavior of electron concentration in discharge is determined. The transmission spectra of 1D EBG structure formed solely by plasma in the X-waveguide are measured. The amplitudes of short ( 200 ns) and powerful (50 kW) microwave pulses at frequency of 9.15 GHz are strongly suppressed (more than on 40 dB) when plasma structure exists. The propagation of these powerful microwave pulses through the triangular metallic 2D EBG structure with the plasma control elements is investigated, too. It is shown that the transmission of the 2D EBG structure at the angle of 45o ceases quickly (during a few tenth of nanoseconds) when plasma acts as a compensator of defect in the front row of the structure. On the contrary, the transmission arises quickly once plasma acts as an additional defect. The support of BRFBR-CNRS grant F15F-004 is acknowledged.

  4. A nonlinear variable structure stabilizer for power system stability

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Y.; Jiang, L.; Cheng, S.; Chen, D. (Huazhong Univ. of Science and Technology, Wuhan (China). Dept. of Electrical Power Engineering); Malik, O.P.; Hope, G.S. (Univ. of Calgary, Alberta (Canada). Dept. of Electrical and Computer Engineering)

    1994-09-01

    A nonlinear variable structure stabilizer is proposed in this paper. Design of this stabilizer involves the nonlinear transformation technique, the variable structure control technique and the linear system theory. Performance of the proposed nonlinear variable structure controller in a single machine connected to an infinite bus power and a multi-machine system with multi-mode oscillations is simulated. The responses of the system with the proposed stabilizer are compared with those obtained with some other kinds of stabilizers when the system is subjected to a variety of disturbances. Simulation results show that the nonlinear variable structure stabilizer gives satisfactory dynamic performance and good robustness.

  5. Nonlinear and Variable Structure Excitation Controller for Power System Stability

    Institute of Scientific and Technical Information of China (English)

    Wang Ben; Ronnie Belmans

    2006-01-01

    A new nonlinear variable structure excitation controller is proposed. Its design combines the differential geometry theory and the variable structure controlling theory. The mathematical model in the form of "an affine nonlinear system" is set up for the control of a large-scale power system. The static and dynamic performances of the nonlinear variable structure controller are simulated. The response of system with the controller proposed is compared to that of the nonlinear optimal controller when the system is subjected to a variety of disturbances. Simulation results show that the nonlinear variable structure excitation controller gives more satisfactorily static and dynamic performance and better robustness.

  6. Structural Power and International Relations Analysis: "Fill your basket, get your preferences"

    OpenAIRE

    Pustovitovskij, Andrej; Kremer, Jan-Frederik

    2011-01-01

    In this article, we will address current deficits of the study of power in IR by introducing a new concept of structural power. After briefly presenting existing concepts of relational power, of structural power as well as of conceptualizing power as the possession of resources (power-as-resources), we will introduce our concept of structural power as an approach suitable for bridging the gap between existing concepts (by strongly focusing on the importance of the structural level). We will s...

  7. A radiation hard bipolar monolithic front-end readout

    CERN Document Server

    Baschirotto, A; Cappelluti, I; Castello, R; Cermesoni, M; Gola, A; Pessina, G; Pistolesi, E; Rancoita, P G; Seidman, A

    1999-01-01

    A fast bipolar monolithic charge sensitive preamplifier (CSP), implemented in the monolithic 2 mu m BiCMOS technology (called HF2CMOS) was designed and built in a quad monolithic chip. Studies of radiation effects in the CSP $9 performance, from non-irradiated and up to neutron irradiation of 5.3*10/sup 14/ n/cm/sup 2/, have confirmed that the use of bipolar npn transistors is suitable for the radiation level of the future LHC collider environment. The CSP $9 presents a new circuit solution for obtaining adequate slew rate performances which results in an integral linearity better than 0.8554330n 5 V at 20 ns of shaping time, regardless of the bias current selected for the CSP. This way $9 the bias current of the CSP can be set for optimizing the power dissipation with respect to series and parallel noise, especially useful when the CSP is put in a radiation environment. A prototype test with a novel monolithic 20 ns $9 time constant RC-CR shaper, capable to sum up four inputs has been also realized, featurin...

  8. Monolithically integrated AlN/GaN electronics for harsh environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Recently, resonant-tunneling-diode (RTD) based circuits employing monolithically-integrated RTD on high electron mobility (HEMT) structures have been developed in a...

  9. Influence of community structure on the synchronization of power network

    Science.gov (United States)

    Yang, Li-Xin; Jiang, Jun; Liu, Xiao-Jun

    2016-12-01

    This paper studies the synchronizability of power network with community structure. Second-order Kuramoto-like oscillators with dissimilar natural frequencies are used as a coarse-scale model for an electrical power network that contains generators and consumers. The impact of community structure on frequency synchronization of power network is investigated, focusing on the parameters such as community strength, community number and connection strategy between communities. Numerical simulations show that increasing the community strength above a certain critical threshold or adding new communities to the network will be beneficial for the synchronization. Of course, connecting high-degree nodes among communities will be a best strategy to enhance synchronization. Furthermore, it is observed that the synchronizability of the network is significantly influenced by adding new links with different characteristics.

  10. The significance of structural power in Strategic Environmental Assessment

    DEFF Research Database (Denmark)

    Hansen, Anne Merrild; Kørnøv, Lone; Cashmore, Matthew Asa

    2013-01-01

    This article presents a study of how power dynamics enables and constrains the influence of actors upon decision-making and Strategic Environmental Assessment (SEA). Based on Anthony Giddens structuration theory (ST), a model for studying power dynamics in strategic decision-making processes......, that actors influence both outcome and frames for strategic decision making and attention needs to be on not only the formal interactions between SEA process and strategic decision-making process but also on informal interaction and communication between actors. The informal structures shows crucial...... theory is found to provide an interesting and wider lens through which to view and analyse power dynamics in strategic decision-making. The article ends by considering possibilities for future research and practice within the IA field....

  11. Lectin-carbohydrate interactions on nanoporous gold monoliths.

    Science.gov (United States)

    Tan, Yih Horng; Fujikawa, Kohki; Pornsuriyasak, Papapida; Alla, Allan J; Ganesh, N Vijaya; Demchenko, Alexei V; Stine, Keith J

    2013-07-01

    Monoliths of nanoporous gold (np-Au) were modified with self-assembled monolayers of octadecanethiol (C18-SH), 8-mercaptooctyl α-D-mannopyranoside (αMan-C8-SH), and 8-mercapto-3,6-dioxaoctanol (HO-PEG2-SH), and the loading was assessed using thermogravimetric analysis (TGA). Modification with mixed SAMs containing αMan-C8-SH (at a 0.20 mole fraction in the SAM forming solution) with either octanethiol or HO-PEG2-SH was also investigated. The np-Au monoliths modified with αMan-C8-SH bind the lectin Concanavalin A (Con A), and the additional mass due to bound protein was assessed using TGA analysis. A comparison of TGA traces measured before and after exposure of HO-PEG2-SH modified np-Au to Con A showed that the non-specific binding of Con A was minimal. In contrast, np-Au modified with octanethiol showed a significant mass loss due to non-specifically adsorbed Con A. A significant mass loss was also attributed to binding of Con A to bare np-Au monoliths. TGA revealed a mass loss due to the binding of Con A to np-Au monoliths modified with pure αMan-C8-SH. The use of mass losses determined by TGA to compare the binding of Con A to np-Au monoliths modified by mixed SAMs of αMan-C8-SH and either octanethiol or HO-PEG2-SH revealed that binding to mixed SAM modified surfaces is specific for the mixed SAMs with HO-PEG2-SH but shows a significant contribution from non-specific adsorption for the mixed SAMs with octanethiol. Minimal adsorption of immunoglobulin G (IgG) and peanut agglutinin (PNA) towards the mannoside modified np-Au monoliths was demonstrated. A greater mass loss was found for Con A bound onto the monolith than for either IgG or PNA, signifying that the mannose presenting SAMs in np-Au retain selectivity for Con A. TGA data also provide evidence that Con A bound to the αMan-C8-SH modified np-Au can be eluted by flowing a solution of methyl α-D-mannopyranoside through the structure. The presence of Con A proteins on the modified np-Au surface was

  12. On the correlation between the porous structure and the electrochemical response of powdered and monolithic carbon aerogels as electrodes for capacitive deionization

    Science.gov (United States)

    Macías, C.; Lavela, P.; Rasines, G.; Zafra, M. C.; Tirado, J. L.; Ania, C. O.

    2016-10-01

    The combined effect of resorcinol/catalyst (100≤R/C≤800) and resorcinol/water (0.04≤R/W≤0.13) molar ratio on the textural and capacitive properties of carbon aerogels with potential application for capacitive deionization has been evaluated. Activated and pyrolyzed aerogels were synthesized by the sol-gel polymerization of resorcinol-formaldehyde mixtures and dried in supercritical conditions. Data show that high R/C and R/W molar ratios lead to materials with large pores in the mesopore range, whereas the surface area and micropore volumes remain somewhat the same. The activation of the aerogels increased the differences in the specific surface and micropore volumes due to the development of microporosity. This effect was more remarkable for the samples with low R/C whatever the R/W ratio, indicating that the carbon aerogel obtained using high amounts of catalyst are more prone to be activated. Regarding the electrochemical features of the aerogels, low capacitance values were measured in aerogels combining low R/W and high R/C and reciprocally low R/C and high R/W molar ratios, due to their higher resistance. Polarization resistances were found to be slightly higher for the pyrolyzed than for activated aerogels, and followed a decreasing trend with the mesoporosity, indicating the outstanding contribution of the mesoporous network to provide a good kinetic response. The desalting capacity of monolithic aerogels showed a simultaneous dependence with the surface area and the resistivity of the electrodes, pointing out the importance of performing electrochemical measurements in adequate cell configurations (i.e., desalting units) upon the intended application.

  13. High surface area, high permeability carbon monoliths

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, R.R.; Schroeder, J.L. [Sandia National Labs., Albuquerque, NM (United States). Organic Materials Processing Dept.

    1994-12-31

    The goal of this work is to prepare carbon monoliths having precisely tailored pore size distribution. Prior studies have demonstrated that poly(acrylonitrile) can be processed into a precursor having tailored macropore structure. Since the macropores were preserved during pyrolysis, this synthetic process provided a route to porous carbon having macropores with size =0.1 to 10{mu}m. No micropores of size <2 nm could be detected in the carbon, however, by nitrogen adsorption. In the present work, the authors have processed a different polymer, poly(vinylidene chloride) into a macroporous precursor, Pyrolysis produced carbon monoliths having macropores derived from the polymer precursor as well as extensive microporosity produced during the pyrolysis of the polymer. One of these carbons had BET surface area of 1,050 m{sup 2}/g and about 1.2 cc/g total pore volume, with about 1/3 of the total pore volume in micropores and the remainder in 1{mu}m macropores. No mesopores in the intermediate size range could be detected by nitrogen adsorption. Carbon materials having high surface area as well as micron size pores have potential applications as electrodes for double layer supercapacitors containing liquid electrolyte, or as efficient media for performing chemical separations.

  14. Catastrophic failure of a monolithic zirconia prosthesis.

    Science.gov (United States)

    Chang, Jae-Seung; Ji, Woon; Choi, Chang-Hoon; Kim, Sunjai

    2015-02-01

    Recently, monolithic zirconia restorations have received attention as an alternative to zirconia veneered with feldspathic porcelain to eliminate chipping failures of veneer ceramics. In this clinical report, a patient with mandibular edentulism received 4 dental implants in the interforaminal area, and a screw-retained monolithic zirconia prosthesis was fabricated. The patient also received a maxillary complete removable dental prosthesis over 4 anterior roots. At the 18-month follow-up, all of the zirconia cylinders were seen to be fractured, and the contacting abutment surfaces had lost structural integrity. The damaged abutments were replaced with new abutments, and a new prosthesis was delivered with a computer-assisted design and computer-assisted manufacturing fabricated titanium framework with denture teeth and denture base resins. At the 6-month recall, the patient did not have any problems. Dental zirconia has excellent physical properties; however, care should be taken to prevent excessive stresses on the zirconia cylinders when a screw-retained zirconia restoration is planned as a definitive prosthesis.

  15. Ultrasonic transformation of micelle structures: effect of frequency and power.

    Science.gov (United States)

    Yusof, Nor Saadah Mohd; Ashokkumar, Muthupandian

    2015-05-01

    A comprehensive investigation on the effect of ultrasonic frequency and power on the structural transformation of CTABr/NaSal micelles has been carried out. Sonication of this micelle system at various ultrasonic frequencies and power resulted in the formation and separation of two types of micelles. High viscoelastic threadlike micelles of ∼ 2 nm in diameter and several μm in length and tubular micelles possessing a viscosity slightly above that of water with ∼ 30-50 nm diameter and few hundred nm length. The structural transformation of micelles was induced by the shear forces generated during acoustic cavitation. At a fixed acoustic power of 40 W, the structural transformation was found to decrease from 211 to 647 kHz frequency due to the decreasing shear forces generated, as evidenced by rheological measurements and cryo-TEM images. At 355 kHz, an increase in the structural transformation was observed with an increase in acoustic power. These findings provide a knowledge base that could be useful for the manipulation of viscosity of micelles that may have applications in oil industry.

  16. 3D-Printed MOF Monoliths for Gas Adsorption Processes.

    Science.gov (United States)

    Thakkar, Harshul; Eastman, Stephen; Al-Naddaf, Qasim; Rownaghi, Ali Asghar; Rezaei, Fateme

    2017-09-27

    Metal-Organic Frameworks (MOFs) have shown promising performance in separation, adsorption, reaction and storage of various industrial gases, however, their large-scale applications have been hampered by the lack of a proper strategy to formulate them into scalable gas-solid contactors. Herein, we report fabrication of MOF monoliths using 3D printing technique and evaluation of their adsorptive performance in CO2 removal from air. The 3D-printed MOF-74(Ni) and UTSA-16(Co) monoliths with MOF loadings as high as 80 and 85 wt %, respectively were developed and their physical and structural properties were characterized and compared with those of MOF powders. Our adsorption experiments showed that upon exposure to 5,000 ppm (0.5%) CO2 at 25 ºC, the MOF-74(Ni) and UTSA-16(Co) monoliths can adsorb CO2 with the uptake capacity of 1.35 and 1.31 mmol/g, respectively, which are 79 and 87% of the capacity of their MOF analogues under the same conditions. Furthermore, a stable performance was obtained for self-standing 3D-printed monolithic structures with relatively good adsorption kinetics. The preliminary findings reported in this investigation highlight the advantage of robocasting (3D printing) technique for shaping MOF materials into practical configurations that are suitable for various gas separation applications.

  17. $\\beta$-BaB$_2$O$_4$ deep UV monolithic walk-off compensating tandem

    CERN Document Server

    Friebe, J; Isaenko, L; Moldenhauer, K; Rasel, E M; Yelisseyev, A; Zondy, J J

    2005-01-01

    The generation of watt-level cw narrow-linewidth sources at specific deep UV wavelengths corresponding to atomic cooling transitions usually employs external cavity-enhanced second-harmonic generation (SHG) of moderate-power visible lasers in birefringent materials. In this work, we investigate a novel approach to cw deep-UV generation by employing the low-loss BBO in a monolithic walkoff-compensating structure [Zondy {\\it{et al}}, J. Opt. Soc. Am. B {\\bf{20}} (2003) 1675] to simultaneously enhance the effective nonlinear coefficient while minimizing the UV beam ellipticity under tight focusing. As a preliminary step to cavity-enhanced operation, and in order to apprehend the design difficulties stemming from the extremely low acceptance angle of BBO, we investigate and analyze the single-pass performance of a $L_c=8 $mm monolithic walk-off compensating structure made of 2 optically-contacted BBO plates cut for type-I critically phase-matched SHG of a cw $\\lambda=570.4$nm dye laser. As compared with a bulk cr...

  18. Magnetic shielding structure optimization design for wireless power transmission coil

    Science.gov (United States)

    Dai, Zhongyu; Wang, Junhua; Long, Mengjiao; Huang, Hong; Sun, Mingui

    2017-09-01

    In order to improve the performance of the wireless power transmission (WPT) system, a novel design scheme with magnetic shielding structure on the WPT coil is presented in this paper. This new type of shielding structure has great advantages on magnetic flux leakage reduction and magnetic field concentration. On the basis of theoretical calculation of coil magnetic flux linkage and characteristic analysis as well as practical application feasibility consideration, a complete magnetic shielding structure was designed and the whole design procedure was represented in detail. The simulation results show that the coil with the designed shielding structure has the maximum energy transmission efficiency. Compared with the traditional shielding structure, the weight of the new design is significantly decreased by about 41%. Finally, according to the designed shielding structure, the corresponding experiment platform is built to verify the correctness and superiority of the proposed scheme.

  19. Monolithically Integrated Ge-on-Si Active Photonics

    OpenAIRE

    Jifeng Liu

    2014-01-01

    Monolithically integrated, active photonic devices on Si are key components in Si-based large-scale electronic-photonic integration for future generations of high-performance, low-power computation and communication systems. Ge has become an interesting candidate for active photonic devices in Si photonics due to its pseudo-direct gap behavior and compatibility with Si complementary metal oxide semiconductor (CMOS) processing. In this paper, we present a review of the recent progress in Ge-on...

  20. Monolithic Fuel Fabrication Process Development

    Energy Technology Data Exchange (ETDEWEB)

    C. R. Clark; N. P. Hallinan; J. F. Jue; D. D. Keiser; J. M. Wight

    2006-05-01

    The pursuit of a high uranium density research reactor fuel plate has led to monolithic fuel, which possesses the greatest possible uranium density in the fuel region. Process developments in fabrication development include friction stir welding tool geometry and cooling improvements and a reduction in the length of time required to complete the transient liquid phase bonding process. Annealing effects on the microstructures of the U-10Mo foil and friction stir welded aluminum 6061 cladding are also examined.

  1. Data in support of preparation and functionalization of a clickable polycarbonate monolith

    Directory of Open Access Journals (Sweden)

    Yuanrong Xin

    2016-06-01

    Full Text Available This data article provides supplementary figures to the research article entitled, “Phase separation approach to a reactive polycarbonate monolith for “click” modifications” (Xin et al., Polymer, 2015, doi:10.1016/j.polymer.2015.04.008. Here, the nitrogen adsorption/desorption isotherms of the prepared porous polycarbonate monolith are shown to classify its inner structure and calculate the specific surface area. The monoliths were modified by using the thiol-ene click chemistry and the olefin metathesis, which was examined by contact angle measurements, FT-IR, solid state 13C NMR spectroscopy as well as thermogravimetric analysis.

  2. Failure analysis of various monolithic posterior aesthetic dental crowns using finite element method

    Science.gov (United States)

    Porojan, Liliana; Topală, Florin

    2017-08-01

    The aim of the study was to assess the effect of material stiffness and load on the biomechanical performance of the monolithic full-coverage posterior aesthetic dental crowns using finite element analysis. Three restorative materials for monolithic dental crowns were selected for the study: zirconia; lithium disilicate glass-ceramic, and resin-based composite. Stresses were calculated in the crowns for all materials and in the teeth structures, under different load values. The experiments show that dental crowns made from all this new aesthetic materials processed by CAD/CAM technologies would be indicated as monolithic dental crowns for posterior areas.

  3. Stabilization of structure-preserving power networks with market dynamics

    CERN Document Server

    Stegink, Tjerk W; van der Schaft, Arjan J

    2016-01-01

    This paper studies the problem of maximizing the social welfare while stabilizing both the physical power network as well as the market dynamics. For the physical power grid a third-order structure-preserving model is considered involving both frequency and voltage dynamics. By applying the primal-dual gradient method to the social welfare problem, a distributed dynamic pricing algorithm in port-Hamiltonian form is obtained. After interconnection with the physical system a closed-loop port-Hamiltonian system of differential-algebraic equations is obtained, whose properties are exploited to prove local asymptotic stability of the optimal points.

  4. Effect of the presence of an ordered micro-pillar array on the formation of silica monoliths

    NARCIS (Netherlands)

    Detobel, Frederik; Eghbali, Hamed; De Bruyne, Selm; Terryn, Herman; Gardeniers, Han; Desmet, Gert

    2009-01-01

    We report on the synthesis of siloxane-based monoliths in the presence of a two-dimensional, perfectly ordered array of micro-pillars. Both methyltrimethoxysilane- and tetramethoxysilane-based monoliths were considered. The obtained structures were analyzed using scanning-electron microscopy and can

  5. Synthesis and characterization of hierarchically porous metal, metal oxide, and carbon monoliths with highly ordered nanostructure

    Science.gov (United States)

    Grano, Amy Janine

    Hierarchically porous materials are of great interest in such applications as catalysis, separations, fuel cells, and advanced batteries. One such way of producing these materials is through the process of nanocasting, in which a sacrificial template is replicated and then removed to form a monolithic replica. This replica consists of mesopores, which can be ordered or disordered, and bicontinuous macropores, which allow flow throughout the length of the monolith. Hierarchically porous metal oxide and carbon monoliths with an ordered mesopores system are synthesized for the first time via nanocasting. These replicas were used as supports for the deposition of silver particles and the catalytic efficiency was evaluated. The ordered silica template used in producing these monoliths was also used for an in-situ TEM study involving metal nanocasting, and an observation of the destruction of the silica template during nanocasting made. Two new methods of removing the silica template were developed and applied to the synthesis of copper, nickel oxide, and zinc oxide monoliths. Finally, hollow fiber membrane monoliths were examined via x-ray tomography in an attempt to establish the presence of this structure throughout the monolith.

  6. Monolithic microwave integrated circuits for sensors, radar, and communications systems; Proceedings of the Meeting, Orlando, FL, Apr. 2-4, 1991

    Science.gov (United States)

    Leonard, Regis F. (Editor); Bhasin, Kul B. (Editor)

    1991-01-01

    Consideration is given to MMICs for airborne phased arrays, monolithic GaAs integrated circuit millimeter wave imaging sensors, accurate design of multiport low-noise MMICs up to 20 GHz, an ultralinear low-noise amplifier technology for space communications, variable-gain MMIC module for space applications, a high-efficiency dual-band power amplifier for radar applications, a high-density circuit approach for low-cost MMIC circuits, coplanar SIMMWIC circuits, recent advances in monolithic phased arrays, and system-level integrated circuit development for phased-array antenna applications. Consideration is also given to performance enhancement in future communications satellites with MMIC technology insertion, application of Ka-band MMIC technology for an Orbiter/ACTS communications experiment, a space-based millimeter wave debris tracking radar, low-noise high-yield octave-band feedback amplifiers to 20 GHz, quasi-optical MESFET VCOs, and a high-dynamic-range mixer using novel balun structure.

  7. The changing structure of the electric power industry: An update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The U. S. electric power industry today is on the road to restructuring a road heretofore uncharted. While parallels can be drawn from similar journeys taken by the airline industry, the telecommunications industry, and, most recently, the natural gas industry, the electric power industry has its own unique set of critical issues that must be resolved along the way. The transition will be from a structure based on a vertically integrated and regulated monopoly to one equipped to function successfully in a competitive market. The long-standing traditional structure of the electric power industry is the result of a complex web of events that have been unfolding for over 100 years. Some of these events had far-reaching and widely publicized effects. Other major events took the form of legislation. Still other events had effects that are less obvious in comparison (e.g., the appearance of technologies such as transformers and steam and gas turbines, the invention of home appliances, the man-made fission of uranium), and it is likely that their significance in the history of the industry has been obscured by the passage of time. Nevertheless, they, too, hold a place in the underpinnings of today`s electric industry structure. The purpose of this report, which is intended for both lay and technical readers, is twofold. First, it is a basic reference document that provides a comprehensive delineation of the electric power industry and its traditional structure, which has been based upon its monopoly status. Second, it describes the industry`s transition to a competitive environment by providing a descriptive analysis of the factors that have contributed to the interest in a competitive market, proposed legislative and regulatory actions, and the steps being taken by the various components of the industry to meet the challenges of adapting to and prevailing in a competitive environment.

  8. A monolithic thin film electrochromic window

    Energy Technology Data Exchange (ETDEWEB)

    Goldner, R.B.; Arntz, F.O.; Berera, G.; Haas, T.E.; Wong, K.K. (Tufts Univ., Medford, MA (United States). Electro-Optics Technology Center); Wei, G. (Mobil Solar Energy Corp., Billerica, MA (United States)); Yu, P.C. (PPG Industries, Inc., Monroeville, PA (United States))

    1991-01-01

    Three closely related thin film solid state ionic devices that are potentially important for applications are: electrochromic smart windows, high energy density thin film rechargeable batteries, and thin film electrochemical sensors. Each usually has at least on mixed ion/electron conductor, an electron-blocking ion conductor, and an ion-blocking electron conductor, and many of the technical issues associated with thin film solid state ionics are common to all three devices. Since the electrochromic window has the added technical requirement of electrically-controlled optical modulation, (over the solar spectrum), and since research at the authors' institution has focused primarily on the window structure, this paper will address the electrochromic window, and particularly a monolithic variable reflectivity electrochromic window, as an illustrative example of some of the challenges and opportunities that are confronting the thin film solid state ionics community. 33 refs.

  9. A monolithic thin film electrochromic window

    Energy Technology Data Exchange (ETDEWEB)

    Goldner, R.B.; Arntz, F.O.; Berera, G.; Haas, T.E.; Wong, K.K. [Tufts Univ., Medford, MA (United States). Electro-Optics Technology Center; Wei, G. [Mobil Solar Energy Corp., Billerica, MA (United States); Yu, P.C. [PPG Industries, Inc., Monroeville, PA (United States)

    1991-12-31

    Three closely related thin film solid state ionic devices that are potentially important for applications are: electrochromic smart windows, high energy density thin film rechargeable batteries, and thin film electrochemical sensors. Each usually has at least on mixed ion/electron conductor, an electron-blocking ion conductor, and an ion-blocking electron conductor, and many of the technical issues associated with thin film solid state ionics are common to all three devices. Since the electrochromic window has the added technical requirement of electrically-controlled optical modulation, (over the solar spectrum), and since research at the authors` institution has focused primarily on the window structure, this paper will address the electrochromic window, and particularly a monolithic variable reflectivity electrochromic window, as an illustrative example of some of the challenges and opportunities that are confronting the thin film solid state ionics community. 33 refs.

  10. A Study on Salt Attack Protection of Structural and Finishing Materials in Power Plant Structures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, W.B.; Kweon, K.J.; Suh, Y.P.; Nah, H.S.; Lee, K.J.; Park, D.S.; Jo, Y.K. [Korea Electric Power Research Institute, Taejeon (Korea, Republic of)

    1997-12-31

    This is a final report written by both KEPRI and KICT as a co-operative research titled {sup A} study on Salt Protection of Structural and Finishings in Power Plant Structures{sup .} This study presented the methods to prevent the chloride-induced corrosion of power plant structures through collection and analysis of research datum relating to design, construction and maintenance for the prevention of structural and finishing materials, thru material performance tests for anti-corrosion under many kinds of chloride-induced corrosion environments. As a result, this study proposed the guidelines for design, construction and maintenance of power plant structures due to chloride-induced corrosion. (author). 257 refs., 111 figs., 86 tabs.

  11. Low-jitter and high-power 40 GHz all-active mode-locked lasers

    DEFF Research Database (Denmark)

    Yvind, Kresten; Larsson, David; Christiansen, Lotte Jin

    2004-01-01

    A novel design strategy for the epitaxial structure of monolithic mode-locked semiconductor lasers is presented. Using an all-active design, we fabricate 40-GHz lasers generating 2.8-ps almost chirp-free pulses with record low high-frequency jitter and more than 7-mW fiber coupled output power....

  12. Seismic design and analysis of nuclear power plant structures

    Institute of Scientific and Technical Information of China (English)

    Pentti Varpasuo

    2013-01-01

    The seismic design and analysis of nuclear power plant (NPP) begin with the seismic hazard assessment and design ground motion development for the site.The following steps are needed for the seismic hazard assessment and design ground motion development:a.the development of regional seismo-tectonic model with seismic source areas within 500 km radius centered to the site; b.the development of strong motion prediction equations;c.logic three development for taking into account uncertainties and seismic hazard quantification; d.the development of uniform hazard response spectra for ground motion at the site; e.simulation of acceleration time histories compatible with uniform hazard response spectra.The following phase two in seismic design of NPP structures is the analysis of structural response for the design ground motion.This second phase of the process consists of the following steps:a.development of structural models of the plant buildings; b.development of the soil model underneath the plant buildings for soil-structure interaction response analysis; c.determination of in-structure response spectra for the plant buildings for the equipment response analysis.In the third phase of the seismic design and analysis the equipment is analyzed on the basis of in-structure response spectra.For this purpose the structural models of the mechanical components and piping in the plant are set up.In large 3D-structural models used today the heaviest equipment of the primary coolant circuit is included in the structural model of the reactor building.In the fourth phase the electrical equipment and automation and control equipment are seismically qualified with the aid of the in-structure spectra developed in the phase two using large three-axial shaking tables.For this purpose the smoothed envelope spectra for calculated in-structure spectra are constructed and acceleration time is fitted to these smoothed envelope spectra.

  13. Monolithically integrated absolute frequency comb laser system

    Energy Technology Data Exchange (ETDEWEB)

    Wanke, Michael C.

    2016-07-12

    Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  14. Nanosecond monolithic CMOS readout cell

    Science.gov (United States)

    Souchkov, Vitali V.

    2004-08-24

    A pulse shaper is implemented in monolithic CMOS with a delay unit formed of a unity gain buffer. The shaper is formed of a difference amplifier having one input connected directly to an input signal and a second input connected to a delayed input signal through the buffer. An elementary cell is based on the pulse shaper and a timing circuit which gates the output of an integrator connected to the pulse shaper output. A detector readout system is formed of a plurality of elementary cells, each connected to a pixel of a pixel array, or to a microstrip of a plurality of microstrips, or to a detector segment.

  15. Compact monolithic capacitive discharge unit

    Science.gov (United States)

    Roesler, Alexander W.; Vernon, George E.; Hoke, Darren A.; De Marquis, Virginia K.; Harris, Steven M.

    2007-06-26

    A compact monolithic capacitive discharge unit (CDU) is disclosed in which a thyristor switch and a flyback charging circuit are both sandwiched about a ceramic energy storage capacitor. The result is a compact rugged assembly which provides a low-inductance current discharge path. The flyback charging circuit preferably includes a low-temperature co-fired ceramic transformer. The CDU can further include one or more ceramic substrates for enclosing the thyristor switch and for holding various passive components used in the flyback charging circuit. A load such as a detonator can also be attached directly to the CDU.

  16. Remotely detected NMR for the characterization of flow and fast chromatographic separations using organic polymer monoliths.

    Science.gov (United States)

    Teisseyre, Thomas Z; Urban, Jiri; Halpern-Manners, Nicholas W; Chambers, Stuart D; Bajaj, Vikram S; Svec, Frantisek; Pines, Alexander

    2011-08-01

    An application of remotely detected magnetic resonance imaging is demonstrated for the characterization of flow and the detection of fast, small molecule separations within hypercrosslinked polymer monoliths. The hyper-cross-linked monoliths exhibited excellent ruggedness, with a transit time relative standard deviation of less than 2.1%, even after more than 300 column volumes were pumped through at high pressure and flow. Magnetic resonance imaging enabled high-resolution intensity and velocity-encoded images of mobile phase flow through the monolith. The images confirm that the presence of a polymer monolith within the capillary disrupts the parabolic laminar flow profile that is characteristic of mobile phase flow within an open tube. As a result, the mobile phase and analytes are equally distributed in the radial direction throughout the monolith. Also, in-line monitoring of chromatographic separations of small molecules at high flow rates is shown. The coupling of monolithic chromatography columns and NMR provides both real-time peak detection and chemical shift information for small aromatic molecules. These experiments demonstrate the unique power of magnetic resonance, both direct and remote, in studying chromatographic processes.

  17. Synthesis of novel hierarchical ZSM-5 monoliths and their application in trichloroethylene removal

    Institute of Scientific and Technical Information of China (English)

    João Pires; Ana C.Fernandes; Divakar Duraiswami

    2014-01-01

    A self-supporting ZSM-5 monolith with a hierarchical porosity was prepared using polyurethane foam (PUF) as a structural template and a hydrothermal synthesis procedure. The synthesized monolith was characterized and investigated towards the adsorption and catalytic oxidation of trichloroethylene (TCE). Adsorption of TCE was studied gravimetrically and oxidation of TCE was studied using a vapor-phase down-flow reactor. Monolithic ZSM-5 displayed good sorption proper-ties and completely oxidized TCE. Conversion levels of 50%and 90%were achieved at reduced temperatures (by~50 °C) when compared with the conversion temperatures obtained from the powder counterparts. Besides the activity of the monolith towards TCE adsorption and oxidation, it was stable and enhanced diffusion, thereby reducing pressure drops to a great extent owing to its hierarchical porous nature.

  18. Fabrication of interfacial functionalized porous polymer monolith and its adsorption properties of copper ions.

    Science.gov (United States)

    Han, Jiaxi; Du, Zhongjie; Zou, Wei; Li, Hangquan; Zhang, Chen

    2014-07-15

    The interfacial functionalized poly (glycidyl methacrylate) (PGMA) porous monolith was fabricated and applied as a novel porous adsorbent for copper ions (Cu(2+)). PGMA porous material with highly interconnected pore network was prepared by concentrated emulsion polymerization template. Then polyacrylic acid (PAA) was grafted onto the interface of the porous monolith by the reaction between the epoxy group on PGMA and a carboxyl group on PAA. Finally, the porous monolith was interfacial functionalized by rich amount of carboxyl groups and could adsorb copper ions effectively. The chemical structure and porous morphology of the porous monolith were measured by Fourier transform infrared spectroscopy and scanning electron microscopy. Moreover, the effects of pore size distribution, pH value, co-existing ions, contacting time, and initial concentrations of copper ions on the adsorption capacity of the porous adsorbents were studied.

  19. Sandwich-structured hollow fiber membranes for osmotic power generation

    KAUST Repository

    Fu, Feng Jiang

    2015-11-01

    In this work, a novel sandwich-structured hollow fiber membrane has been developed via a specially designed spinneret and optimized spinning conditions. With this specially designed spinneret, the outer layer, which is the most crucial part of the sandwich-structured membrane, is maintained the same as the traditional dual-layer membrane. The inner substrate layer is separated into two layers: (1) an ultra-thin middle layer comprising a high molecular weight polyvinylpyrrolidone (PVP) additive to enhance integration with the outer polybenzimidazole (PBI) selective layer, and (2) an inner-layer to provide strong mechanical strength for the membrane. Experimental results show that a high water permeability and good mechanical strength could be achieved without the expensive post treatment process to remove PVP which was necessary for the dual-layer pressure retarded osmosis (PRO) membranes. By optimizing the composition, the membrane shows a maximum power density of 6.23W/m2 at a hydraulic pressure of 22.0bar when 1M NaCl and 10mM NaCl are used as the draw and feed solutions, respectively. To our best knowledge, this is the best phase inversion hollow fiber membrane with an outer selective PBI layer for osmotic power generation. In addition, this is the first work that shows how to fabricate sandwich-structured hollow fiber membranes for various applications. © 2015 Elsevier B.V.

  20. Seismic margin analysis technique for nuclear power plant structures

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Moon; Choi, In Kil

    2001-04-01

    In general, the Seismic Probabilistic Risk Assessment (SPRA) and the Seismic Margin Assessment(SAM) are used for the evaluation of realistic seismic capacity of nuclear power plant structures. Seismic PRA is a systematic process to evaluate the seismic safety of nuclear power plant. In our country, SPRA has been used to perform the probabilistic safety assessment for the earthquake event. SMA is a simple and cost effective manner to quantify the seismic margin of individual structural elements. This study was performed to improve the reliability of SMA results and to confirm the assessment procedure. To achieve this goal, review for the current status of the techniques and procedures was performed. Two methodologies, CDFM (Conservative Deterministic Failure Margin) sponsored by NRC and FA (Fragility Analysis) sponsored by EPRI, were developed for the seismic margin review of NPP structures. FA method was originally developed for Seismic PRA. CDFM approach is more amenable to use by experienced design engineers including utility staff design engineers. In this study, detailed review on the procedures of CDFM and FA methodology was performed.

  1. Growth and Transfer of Monolithic Horizontal ZnO Nanowire Superstructures onto Flexible Substrates

    KAUST Repository

    Xu, Sheng

    2010-04-28

    A method of fabricating horizontally aligned ZnO nanowire (NW) arrays with full control over the width and length is demonstrated. A cross-sectional view of the NWs by transmission electron microscopy shows a "mushroom-like" structure. Novel monolithic multisegment superstructures are fabricated by making use of the lateral overgrowth. Ultralong horizontal ZnO NWs of an aspect ratio on the order often thousand are also demonstrated. These horizontal NWs are lifted off and transferred onto a flexible polymer substrate, which may have many great applications in horizontal ZnO NW-based nanosensor arrays, light-emitting diodes, optical gratings, integrated circuit interconnects, and high-output-power alternating-current nanogenerators. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

  2. Green monolithic II-VI vertical-cavity surface-emitting laser operating at room temperature

    Science.gov (United States)

    Kruse, C.; Ulrich, S. M.; Alexe, G.; Roventa, E.; Kröger, R.; Brendemühl, B.; Michler, P.; Gutowski, J.; Hommel, D.

    2004-02-01

    The realization of a monolithic all II-VI-based vertical cavity surface emitting laser (VCSEL) for the green spectral region is reported. Optically pumped lasing operation was achieved up to room temperature using a planar VCSEL structure. Taking advantage of distributed Bragg-reflectors based on MgS/Zn(Cd)Se superlattices as the low-refractive index material and ZnS0.06Se0.94 layers as the high-index material with a refractive index contrast of n = 0.6, a quality factor exceeding Q = 2000 is reached by using only 18 Bragg periods for the bottom DBR and 15 Bragg periods for the top DBR. The threshold power density is 0.32 MW/cm2 at a temperature of 10 K (emission wavelength 498.5 nm) and 1.9 MW/cm2 at room temperature (emission wavelength 502.3 nm).

  3. Transverse modes of a diode-laser pumped monolithic unidirectional non-planar ring laser

    Institute of Scientific and Technical Information of China (English)

    Keying Wu(吴克瑛); Suhui Yang(杨苏辉); Guanghui Wei(魏光辉)

    2003-01-01

    Diode-laser pumped monolithic single-frequency non-planar ring laser has the advantages of compactness,reliability and high efficiency. But when the pump power is high enough, the thermal effect will be seriousand the high-order transverse modes will appear. Therefore the single-mode output power is limited. Inthis paper, the mechanism of generating the high-order transverse modes in the monolithic unidirectionalnon-planar ring cavity is analyzed using ray tracing method. The calculated results are in agreement withthe experiments.

  4. Properties of InGaAs quantum dot saturable absorbers in monolithic mode-locked lasers

    DEFF Research Database (Denmark)

    Thompson, M.G.; Marinelli, C.; Chu, Y.

    Saturable absorbers properties are characterised in monolithic mode-locked InGaAs quantum dot lasers. We analyse the impact of weak quantum confined Stark effect, fast absorber recovery time and low absorber saturation power on the mode-locking performance.......Saturable absorbers properties are characterised in monolithic mode-locked InGaAs quantum dot lasers. We analyse the impact of weak quantum confined Stark effect, fast absorber recovery time and low absorber saturation power on the mode-locking performance....

  5. Development of Monolithic Column Materials for the Separation and Analysis of Glycans

    Directory of Open Access Journals (Sweden)

    Allan J. Alla

    2015-02-01

    Full Text Available Monolithic column materials offer great advantages as chromatographic media in bioseparations and as solid-supports in biocatalysis. These single-piece porous materials have an interconnected ligament structure that limits the void volume inside the column, thus increasing the efficiency without sacrificing the permeability. The preparation of monolithic materials is easy, reproducible and has available a wide range of chemistries to utilize. Complex, heterogeneous and isobaric glycan structures require preparation methods that may include glycan release, separation and enrichment prior to a comprehensive and site-specific glycosylation analysis. Monolithic column materials aid that demand, as shown by the results reported by the research works presented in this review. These works include selective capture of glycans and glycoproteins via their interactions with lectins, boronic acids, hydrophobic, and hydrophilic/polar functional groups on monolith surfaces. It also includes immobilization of enzymes trypsin and PNGase F on monoliths to digest and deglycosylate glycoproteins and glycopeptides, respectively. The use of monolithic capillary columns for glycan separations through nano-liquid chromatography (nano-LC and capillary electrochromatography (CEC and coupling these columns to MS instruments to create multidimensional systems show the potential in the development of miniaturized, high-throughput and automated systems of glycan separation and analysis.

  6. Fabrication of interfacial functionalized porous polymer monolith and its adsorption properties of copper ions

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jiaxi; Du, Zhongjie; Zou, Wei; Li, Hangquan; Zhang, Chen, E-mail: zhangch@mail.buct.edu.cn

    2014-07-15

    Highlights: • Interface functionalized PGMA porous monolith was fabricated. • The adsorption capacity of Cu{sup 2+} was 35.3 mg/g. • The effects of porous structure on the adsorption of Cu{sup 2+} were studied. • The adsorption behaviors of porous monolith were studied. - Abstract: The interfacial functionalized poly (glycidyl methacrylate) (PGMA) porous monolith was fabricated and applied as a novel porous adsorbent for copper ions (Cu{sup 2+}). PGMA porous material with highly interconnected pore network was prepared by concentrated emulsion polymerization template. Then polyacrylic acid (PAA) was grafted onto the interface of the porous monolith by the reaction between the epoxy group on PGMA and a carboxyl group on PAA. Finally, the porous monolith was interfacial functionalized by rich amount of carboxyl groups and could adsorb copper ions effectively. The chemical structure and porous morphology of the porous monolith were measured by Fourier transform infrared spectroscopy and scanning electron microscopy. Moreover, the effects of pore size distribution, pH value, co-existing ions, contacting time, and initial concentrations of copper ions on the adsorption capacity of the porous adsorbents were studied.

  7. Power-transfer effects in monomode optical nonlinear waveguiding structures.

    Science.gov (United States)

    Jakubczyk, Z; Jerominek, H; Patela, S; Tremblay, R; Delisle, C

    1987-09-01

    We describe power-transfer effects, over a certain threshold, among constituents of planar waveguiding structures consisting of an optical linear layer deposited onto a nonlinear substrate (CdS(x)Se(1-x)-doped glass). Proper selection of the thickness of the linear waveguiding film and the refractive index of the linear cladding allows one to obtain optical transistor action and to construct all-optical AND, OR, NOT, and XOR logic gates. The effects appear for the TE(0) guided mode.

  8. Biasable, Balanced, Fundamental Submillimeter Monolithic Membrane Mixer

    Science.gov (United States)

    Siegel, Peter; Schlecht, Erich; Mehdi, Imran; Gill, John; Velebir, James; Tsang, Raymond; Dengler, Robert; Lin, Robert

    2010-01-01

    This device is a biasable, submillimeter-wave, balanced mixer fabricated using JPL s monolithic membrane process a simplified version of planar membrane technology. The primary target application is instrumentation used for analysis of atmospheric constituents, pressure, temperature, winds, and other physical and chemical properties of the atmospheres of planets and comets. Other applications include high-sensitivity gas detection and analysis. This innovation uses a balanced configuration of two diodes allowing the radio frequency (RF) signal and local oscillator (LO) inputs to be separated. This removes the need for external diplexers that are inherently narrowband, bulky, and require mechanical tuning to change frequency. Additionally, this mixer uses DC bias-ability to improve its performance and versatility. In order to solve problems relating to circuit size, the GaAs membrane process was created. As much of the circuitry as possible is fabricated on-chip, making the circuit monolithic. The remainder of the circuitry is precision-machined into a waveguide block that holds the GaAs circuit. The most critical alignments are performed using micron-scale semiconductor technology, enabling wide bandwidth and high operating frequencies. The balanced mixer gets superior performance with less than 2 mW of LO power. This can be provided by a simple two-stage multiplier chain following an amplifier at around 90 GHz. Further, the diodes are arranged so that they can be biased. Biasing pushes the diodes closer to their switching voltage, so that less LO power is required to switch the diodes on and off. In the photo, the diodes are at the right end of the circuit. The LO comes from the waveguide at the right into a reduced-height section containing the diodes. Because the diodes are in series to the LO signal, they are both turned on and off simultaneously once per LO cycle. Conversely, the RF signal is picked up from the RF waveguide by the probe at the left, and flows

  9. Design and evaluation of synthetic silica-based monolithic materials in shrinkable tube for efficient protein extraction.

    Science.gov (United States)

    Alzahrani, Eman; Welham, Kevin

    2011-10-21

    Sample pretreatment is a required step in proteomics in order to remove interferences and preconcentrate the samples. Much research in recent years has focused on porous monolithic materials since they are highly permeable to liquid flow and show high mass transport compared with more common packed beds. These features are due to the micro-structure within the monolithic silica column which contains both macropores that reduce the back pressure, and mesopores that give good interaction with analytes. The aim of this work was to fabricate a continuous porous silica monolithic rod inside a heat shrinkable tube and to compare this with the same material whose surface has been modified with a C(18) phase, in order to use them for preconcentration/extraction of proteins. The performance of the silica-based monolithic rod was evaluated using eight proteins; insulin, cytochrome C, lysozyme, myoglobin, β-lactoglobulin, ovalbumin, hemoglobin, and bovine serum albumin at a concentration of 60 μM. The results show that recovery of the proteins was achieved by both columns with variable yields; however, the C(18) modified silica monolith gave higher recoveries (92.7 to 109.7%) than the non-modified silica monolith (25.5 to 97.9%). Both silica monoliths can be used with very low back pressure indicating a promising approach for future fabrication of the silica monolith inside a microfluidic device for the extraction of proteins from biological media.

  10. Theory analysis and structure optimization design of powered gait orthosis

    Directory of Open Access Journals (Sweden)

    Meng Ning

    2016-03-01

    Full Text Available Patients suffering from paraplegia are special disabled groups in society. In order to help them with lower-limb rehabilitation, a kind of power-assisted gait orthosis is designed. In consideration of the crutches that are rather necessary to keep balance when walking, the effects of crutches on analysis of mechanism cannot be ignored. Based on the gait characteristics, this gait orthosis mechanism is designed, of which the structure is optimized by genetic algorithm and the dynamical model is generated. The periodic movement of hip joints, knee joints, and ankle joints in corrected gait are achieved and the torque can be transferred to the driving force of the back motor and the pushrod according to the orthosis structure. Finally, a verification test shows this design is reasonable and practical.

  11. Monolithic pixels on moderate resistivity substrate and sparsifying readout architecture

    Science.gov (United States)

    Giubilato, P.; Battaglia, M.; Bisello, D.; Caselle, M.; Chalmet, P.; Demaria, L.; Ikemoto, Y.; Kloukinas, K.; Mansuy, S. C.; Mattiazzo, S.; Marchioro, A.; Mugnier, H.; Pantano, D.; Potenza, A.; Rivetti, A.; Rousset, J.; Silvestrin, L.; Snoeys, W.

    2013-12-01

    The LePix projects aim realizing a new generation monolithic pixel detectors with improved performances at lesser cost with respect to both current state of the art monolithic and hybrid pixel sensors. The detector is built in a 90 nm CMOS process on a substrate of moderate resistivity. This allows charge collection by drift while maintaining the other advantages usually offered by MAPS, like having a single piece detector and using a standard CMOS production line. The collection by drift mechanism, coupled to the low capacitance design of the collecting node made possible by the monolithic approach, provides an excellent signal to noise ratio straight at the pixel cell together with a radiation tolerance far superior to conventional un-depleted MAPS. The excellent signal-to-noise performance is demonstrated by the device ability to separate the 6 keV 55Fe double peak at room temperature. To achieve high granularity (10-20 μm pitch pixels) over large detector areas maintaining high readout speed, a completely new compressing architecture has been devised. This architecture departs from the mainstream hybrid pixel sparsification approach, which uses in-pixel logic to reduce data, by using topological compression to minimize pixel area and power consumption.

  12. Microfluidic devices and methods including porous polymer monoliths

    Science.gov (United States)

    Hatch, Anson V; Sommer, Gregory J; Singh, Anup K; Wang, Ying-Chih; Abhyankar, Vinay V

    2014-04-22

    Microfluidic devices and methods including porous polymer monoliths are described. Polymerization techniques may be used to generate porous polymer monoliths having pores defined by a liquid component of a fluid mixture. The fluid mixture may contain iniferters and the resulting porous polymer monolith may include surfaces terminated with iniferter species. Capture molecules may then be grafted to the monolith pores.

  13. Formulation of Aminosilica Adsorbents into 3D-Printed Monoliths and Evaluation of Their CO2 Capture Performance.

    Science.gov (United States)

    Thakkar, Harshul; Eastman, Stephen; Al-Mamoori, Ahmed; Hajari, Amit; Rownaghi, Ali A; Rezaei, Fateme

    2017-03-01

    Amine-based materials have represented themselves as a promising class of CO2 adsorbents; however, their large-scale implementation requires their formulation into suitable structures. In this study, we report formulation of aminosilica adsorbents into monolithic structures through a three-dimensional (3D) printing technique. In particular, 3D-printed monoliths were fabricated using presynthesized silica-supported tetraethylenepentamine (TEPA) and poly(ethylenimine) (PEI) adsorbents using three different approaches. In addition, a 3D-printed bare silica monolith was prepared and post-functionalized with 3-aminopropyltrimethoxysilane (APS). Characterization of the obtained monoliths indicated that aminosilica materials retained their characteristics after being extruded into 3D-printed configurations. Adsorptive performance of amine-based structured adsorbents was also investigated in CO2 capture. Our results indicated that aminosilica materials retain their structural, physical, and chemical properties in the monoliths. In addition, the aminosilica monoliths exhibited adsorptive characteristics comparable to their corresponding powders. This work highlights the importance of adsorbent materials formulations into practical contactors such as monoliths, as the scalabale technology platform, that could facilitate rapid deployment of adsorption-based CO2 capture processes on commercial scales.

  14. Advanced on-chip divider for monolithic microwave VCO's

    Science.gov (United States)

    Peterson, Weddell C.

    1989-01-01

    High frequency division on a monolithic circuit is a critical technology required to significantly enhance the performance of microwave and millimeter-wave phase-locked sources. The approach used to meet this need is to apply circuit design practices which are essentially 'microwave' in nature to the basically 'digital' problem of high speed division. Following investigation of several promising circuit approaches, program phase 1 culminated in the design and layout of an 8.5 GHz (Deep Space Channel 14) divide by four circuit based on a dynamic mixing divider circuit approach. Therefore, during program phase 2, an 8.5 GHz VCO with an integral divider which provides a phase coherent 2.125 GHz reference signal for phase locking applications was fabricated and optimized. Complete phase locked operation of the monolithic GaAs devices (VCO, power splitter, and dynamic divider) was demonstrated both individually and as an integrated unit. The fully functional integrated unit in a suitable test fixture was delivered to NASA for engineering data correlation. Based on the experience gained from this 8.5 GHz super component, a monolithic GaAs millimeter-wave dynamic divider for operation with an external VCO was also designed, fabricated, and characterized. This circuit, which was also delivered to NASA, demonstrated coherent division by four at an input frequency of 24.3 GHz. The high performance monolithic microwave VCO with a coherent low frequency reference output described in this report and others based on this technology will greatly benefit advanced communications systems in both the DoD and commercial sectors. Signal processing and instrumentation systems based on phase-locking loops will also attain enhanced performance at potentially reduced cost.

  15. Advanced on-chip divider for monolithic microwave VCO's

    Science.gov (United States)

    Peterson, Weddell C.

    1989-05-01

    High frequency division on a monolithic circuit is a critical technology required to significantly enhance the performance of microwave and millimeter-wave phase-locked sources. The approach used to meet this need is to apply circuit design practices which are essentially 'microwave' in nature to the basically 'digital' problem of high speed division. Following investigation of several promising circuit approaches, program phase 1 culminated in the design and layout of an 8.5 GHz (Deep Space Channel 14) divide by four circuit based on a dynamic mixing divider circuit approach. Therefore, during program phase 2, an 8.5 GHz VCO with an integral divider which provides a phase coherent 2.125 GHz reference signal for phase locking applications was fabricated and optimized. Complete phase locked operation of the monolithic GaAs devices (VCO, power splitter, and dynamic divider) was demonstrated both individually and as an integrated unit. The fully functional integrated unit in a suitable test fixture was delivered to NASA for engineering data correlation. Based on the experience gained from this 8.5 GHz super component, a monolithic GaAs millimeter-wave dynamic divider for operation with an external VCO was also designed, fabricated, and characterized. This circuit, which was also delivered to NASA, demonstrated coherent division by four at an input frequency of 24.3 GHz. The high performance monolithic microwave VCO with a coherent low frequency reference output described in this report and others based on this technology will greatly benefit advanced communications systems in both the DoD and commercial sectors. Signal processing and instrumentation systems based on phase-locking loops will also attain enhanced performance at potentially reduced cost.

  16. Strong cation exchange monoliths for HPLC by Reactive Gelation.

    Science.gov (United States)

    Brand, Bastian; Krättli, Martin; Storti, Giuseppe; Morbidelli, Massimo

    2011-08-01

    Polymeric monolithic stationary phases for HPLC can be produced by Reactive Gelation. Unlike the conventional method of using porogens, such novel process consists of a number of separate steps, thus enabling a better control of the quality of the final material. A suspension of polymer nanoparticles in water is produced and subsequently swollen with hydrophobic monomers. The particles are then destabilised (usually by salt addition) to make them aggregate into a large percolating structure, the so-called monolith. Finally, the added monomer can then be polymerised to harden the structure. In this work, a polystyrene latex is used as the base material and functionalised by introduction of epoxide groups on the surface and subsequent reaction to sulphonic acid groups, yielding a SO3(-) density of 0.7 mmol/g dry material. Morphological investigations show 54% porosity made of 300 nm large pores. Van Deemter measurements of a large protein show no practical influence of diffusion limitations on the plate number. Finally, a preliminary separation of a test protein mixture is shown, demonstrating the potential of using ion-exchange chromatography on Reactive Gelation monoliths.

  17. New monolith technology for automated anion-exchange purification of nucleic acids.

    Science.gov (United States)

    Thayer, J R; Flook, K J; Woodruff, A; Rao, S; Pohl, C A

    2010-04-15

    Synthetic nucleic acid analysis often employs pellicular anion-exchange (AE) chromatography because it supports very high efficiency separations while offering means to control secondary structure, retention and resolution by readily modifiable chromatographic conditions. However, these pellicular anion-exchange (pAE) phases do not offer capacity sufficient for lab-scale oligonucleotide (ON) purification. In contrast, monolithic phases produce fast separations at capacities exceeding their pellicular counterparts, but do not exhibit capacities typical of fully porous, bead-based, anion-exchangers. In order to further increase monolith capacity and obtain the selectivity and mass transfer characteristics of pellicular phases, a surface-functionalized monolith was coated with pAE nanobeads (latexes) usually employed on the pellicular DNAPac phase. The nanobead-coated monolith exhibited chromatographic behaviors typical of polymer AE phases. Based on this observation the monolithic substrate surface porosity and latex diameters were co-optimized to produce a hybrid monolith harboring capacity similar to that of fully porous bead-based phases and peak shape approaching that of the pAE phases. We tested the hybrid monolith on a variety of previously developed pAE capabilities including control of ON selectivity, resolution of derivatized ONs, the ability to resolve RNA ONs harboring aberrant linkages at different positions in a single sequence and separation of phosphorothioate diastereoisomers. We compared the yield and purity of an 8 mg ON sample purified on both the new hybrid monolith and a benchmark AE column based on fully porous monodisperse beads. This comparison included an assessment of the relative selectivities of both columns. Finally, we demonstrated the ability to couple AE ON separations with ESI-MS using an automated desalting protocol. This protocol is also useful for preparing ONs for other assays, such as enzyme treatments, that may be sensitive to

  18. Bias Errors in Measurement of Vibratory Power and Implication for Active Control of Structural Vibration

    DEFF Research Database (Denmark)

    Ohlrich, Mogens; Henriksen, Eigil; Laugesen, Søren

    1997-01-01

    control of vibratory power transmission into structures. This is demonstrated by computer simulations using a theoretical model of a beam structure which is driven by one primary source and two control sources. These simulations reveal the influence of residual errors on power measurements......, and the limitations imposed in active control of structural vibration based upon a strategy of power minimisation....

  19. Monolithic Continuous-Flow Bioreactors

    Science.gov (United States)

    Stephanopoulos, Gregory; Kornfield, Julia A.; Voecks, Gerald A.

    1993-01-01

    Monolithic ceramic matrices containing many small flow passages useful as continuous-flow bioreactors. Ceramic matrix containing passages made by extruding and firing suitable ceramic. Pores in matrix provide attachment medium for film of cells and allow free movement of solution. Material one not toxic to micro-organisms grown in reactor. In reactor, liquid nutrients flow over, and liquid reaction products flow from, cell culture immobilized in one set of channels while oxygen flows to, and gaseous reaction products flow from, culture in adjacent set of passages. Cells live on inner surfaces containing flowing nutrient and in pores of walls of passages. Ready access to nutrients and oxygen in channels. They generate continuous high yield characteristic of immobilized cells, without large expenditure of energy otherwise incurred if necessary to pump nutrient solution through dense biomass as in bioreactors of other types.

  20. Monolithic cells for solar fuels.

    Science.gov (United States)

    Rongé, Jan; Bosserez, Tom; Martel, David; Nervi, Carlo; Boarino, Luca; Taulelle, Francis; Decher, Gero; Bordiga, Silvia; Martens, Johan A

    2014-12-07

    Hybrid energy generation models based on a variety of alternative energy supply technologies are considered the best way to cope with the depletion of fossil energy resources and to limit global warming. One of the currently missing technologies is the mimic of natural photosynthesis to convert carbon dioxide and water into chemical fuel using sunlight. This idea has been around for decades, but artificial photosynthesis of organic molecules is still far away from providing real-world solutions. The scientific challenge is to perform in an efficient way the multi-electron transfer reactions of water oxidation and carbon dioxide reduction using holes and single electrons generated in an illuminated semiconductor. In this tutorial review the design of photoelectrochemical (PEC) cells that combine solar water oxidation and CO2 reduction is discussed. In such PEC cells simultaneous transport and efficient use of light, electrons, protons and molecules has to be managed. It is explained how efficiency can be gained by compartmentalisation of the water oxidation and CO2 reduction processes by proton exchange membranes, and monolithic concepts of artificial leaves and solar membranes are presented. Besides transferring protons from the anode to the cathode compartment the membrane serves as a molecular barrier material to prevent cross-over of oxygen and fuel molecules. Innovative nano-organized multimaterials will be needed to realise practical artificial photosynthesis devices. This review provides an overview of synthesis techniques which could be used to realise monolithic multifunctional membrane-electrode assemblies, such as Layer-by-Layer (LbL) deposition, Atomic Layer Deposition (ALD), and porous silicon (porSi) engineering. Advances in modelling approaches, electrochemical techniques and in situ spectroscopies to characterise overall PEC cell performance are discussed.

  1. Binderless Composite Electrode Monolith from Carbon Nanotube and Biomass Carbon Activated by H2 SO4 and CO2 Gas for Supercapacitor

    Science.gov (United States)

    Deraman, M.; Ishak, M. M.; Farma, R.; Awitdrus, Taer, E.; Talib, I. A.; Omar, R.

    2011-12-01

    Binderless composite electrodes in the monolithic form prepared from carbon nanotubes (CNTs) and self-adhesive carbon grains (SACG) from fibers of oil palm empty fruit bunch were studied as an electrode in a supercapacitor. The green monoliths (GMs) were prepared from three different types of precursors, SACG, SACG treated with 0.4 Molar H2 SO4 and mixture of SACG and 5% CNTs (by weight) treated with 0.4 Molar H2 SO4 , respectively. These GMs were carbonized at 600 ° C in N2 gas environment and activated by CO2 gas at 800 ° C for 1 hour to produce activated carbon monoliths (ACMs). The properties of the ACMs (density, porosity, microstructure, structure and electrical conductivity) were found affected by CNTs addition and acid treatment. The acid treatment did not improve the electrochemical behavior of the ACMs used as electrodes (specific capacitance, specific energy and specific power of the supercapacitor) in the supercapacitor cells but CNTs addition improves the equivalent series resistance of the cell.

  2. Impact of structural aging on seismic risk assessment of reinforced concrete structures in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ellingwood, B.; Song, J. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

    1996-03-01

    The Structural Aging Program is addressing the potential for degradation of concrete structural components and systems in nuclear power plants over time due to aging and aggressive environmental stressors. Structures are passive under normal operating conditions but play a key role in mitigating design-basis events, particularly those arising from external challenges such as earthquakes, extreme winds, fires and floods. Structures are plant-specific and unique, often are difficult to inspect, and are virtually impossible to replace. The importance of structural failures in accident mitigation is amplified because such failures may lead to common-cause failures of other components. Structural condition assessment and service life prediction must focus on a few critical components and systems within the plant. Components and systems that are dominant contributors to risk and that require particular attention can be identified through the mathematical formalism of a probabilistic risk assessment, or PRA. To illustrate, the role of structural degradation due to aging on plant risk is examined through the framework of a Level 1 seismic PRA of a nuclear power plant. Plausible mechanisms of structural degradation are found to increase the core damage probability by approximately a factor of two.

  3. The spectral structure and energetics of powerful radio sources

    CERN Document Server

    Harwood, J J; Croston, J H; Stroe, A; Morganti, R; Orru, E

    2014-01-01

    Determining the energy spectrum of an electron population can give key insights into the underlying physics of a radio source; however, the lack of high resolution, broad-bandwidth observations has left many ambiguities in our understanding of radio galaxies. The improved capabilities of telescopes such as the JVLA and LOFAR mean that within the bandwidth of any given observation, a detailed spectral shape can now be produced. We present recent investigations of powerful FR-II radio galaxies at GHz and MHz frequencies and show for the first time their small-scale spectral structure. We highlight problems in traditional methods of analysis and demonstrate how these issues can now be addressed. We present the latest results from low frequency studies which suggest a potential increase in the total energy content of radio galaxy lobes with possible implications for the energetics of the population as a whole.

  4. Cascade Structure of Digital Predistorter for Power Amplifier Linearization

    Directory of Open Access Journals (Sweden)

    E. B. Solovyeva

    2015-12-01

    Full Text Available In this paper, a cascade structure of nonlinear digital predistorter (DPD synthesized by the direct learning adaptive algorithm is represented. DPD is used for linearization of power amplifier (PA characteristic, namely for compensation of PA nonlinear distortion. Blocks of the cascade DPD are described by different models: the functional link artificial neural network (FLANN, the polynomial perceptron network (PPN and the radially pruned Volterra model (RPVM. At synthesis of the cascade DPD there is possibility to overcome the ill conditionality problem due to reducing the dimension of DPD nonlinear operator approximation. Results of compensating nonlinear distortion in Wiener–Hammerstein model of PA at the GSM–signal with four carriers are shown. The highest accuracy of PA linearization is produced by the cascade DPD containing PPN and RPVM.

  5. Monolithic Time Delay Integrated APD Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall goal of the proposed program by Epitaxial Technologies is to develop monolithic time delay integrated avalanche photodiode (APD) arrays with sensitivity...

  6. Optimal parameters of monolithic high-index contrast grating VCSELs

    Science.gov (United States)

    Marciniak, Magdalena; Gebski, Marcin; Dems, Maciej; Czyszanowski, Tomasz

    2016-04-01

    Monolithic High refractive index Contrast Grating (MHCG) allows several-fold size reduction of epitaxial structure of VCSEL and facilitates VCSEL fabrication in all photonic material systems. MHCGs can be fabricated of material which refractive index is higher than 1.75 without the need of the combination of low and high refractive index materials. MHCGs have a great application potential in optoelectronic devices, especially in phosphide- and nitride-based VCSELs, which suffer from the lack of efficient monolithically integrated DBR mirrors. MHCGs can simplify the construction of VCSELs, reducing their epitaxial design to monolithic wafer with carrier confinement and active region inside and etched stripes on both surfaces in post processing. In this paper we present results of numerical analysis of MHCGs as a high reflective mirrors for broad range of refractive indices that corresponds to plethora of materials typically used in optoelectronics. Our calculations base on a three-dimensional, fully vectorial optical model. We investigate the reflectance of the MHCG mirrors of different design as the function of the refractive index and we show the optimal geometrical parameters of MHCG enabling nearly 100% reflectance and broad reflection stop-band. We show that MHCG can be designed based on most of semiconductors materials and for any incident light wavelength from optical spectrum.

  7. Controlled porosity monolithic material as permselective ion exchange membranes.

    Science.gov (United States)

    Huang, Xiaojia; Dasgupta, Purnendu K

    2011-03-18

    Ion exchange membranes (IEMs) are used in a variety of analytical devices, including suppressors, eluent generators and other components used in ion chromatography. Such membranes are flexible and undergo substantial dimensional changes on hydration. Presently the push to miniaturization continues; a resurgent interest in open tubular ion chromatography requires microscale adaptation of these components. Incorporating IEMs in microscale devices is difficult. Although both macroporous and microporous ion exchange materials have been made for use as chromatographic packing, ion exchange material used as membranes are porous only on a molecular scale. Because such pores have vicinal ion exchange sites, ions of the same charge sign as those of the fixed sites are excluded from the IEMs. Monolithic polymers, including ion exchangers derived therefrom, are presently extensively used. When used in a separation column, such a monolithic structure contains an extensively connected porous network. We show here that by controlling the amount of porogen added during the synthesis of monolithic polymers derived from ethylene dimethacrylate - glycidyl methacrylate, which are converted to an anion exchanger by treatment with trimethylamine, it is possible to obtain rigid ion exchange polymers that behave like IEMs and allow only one charge type of ions to pass through, i.e., are permselective. We demonstrate successful open tubular cation chromatography suppressor performance.

  8. Monolithic multinozzle emitters for nanoelectrospray mass spectrometry

    Science.gov (United States)

    Wang, Daojing; Yang, Peidong; Kim, Woong; Fan, Rong

    2011-09-20

    Novel and significantly simplified procedures for fabrication of fully integrated nanoelectrospray emitters have been described. For nanofabricated monolithic multinozzle emitters (NM.sup.2 emitters), a bottom up approach using silicon nanowires on a silicon sliver is used. For microfabricated monolithic multinozzle emitters (M.sup.3 emitters), a top down approach using MEMS techniques on silicon wafers is used. The emitters have performance comparable to that of commercially-available silica capillary emitters for nanoelectrospray mass spectrometry.

  9. 5Gb/s optical logic AND operations using by monolithically integrated photodiode and electroabsorption modulator

    Science.gov (United States)

    Zhang, Y. X.; Zhao, L. J.; Niu, B.; Pan, J. Q.; Wang, W.

    2010-05-01

    A novel EAM/PD monolithically-integrated optical logic element is presented. 5Gb/s optical logic AND gate operations at about -2 V for non-return-to-zero (NRZ) signals with8.4dB extinction ratio and16mW absorbed optical power was demonstrated.

  10. Monolithic formulation of electromechanical systems within the context of hybrid finite elements

    Science.gov (United States)

    Agrawal, Manish; Jog, C. S.

    2017-03-01

    In electromechanical devices, a strong coupling exists between the electromagnetic and displacement field. Due to this strong interaction, a need arises to develop a robust, fully coupled scheme for modeling electromechanical phenomena. With this goal in view, we present a monolithic numerical scheme for modeling fully coupled electromechanical systems. It is shown in the literature that for structural problems, hybrid elements that are based on a two-field variational formulation are less susceptible to locking and provide a robust numerical strategy especially for shell-type structures. Hence, we extend our monolithic formulation to the hybrid finite element framework. Our monolithic formulation is based on a total Lagrangian framework, where the eddy current and structural equations are solved on the reference configuration. Consistent linearization is performed to ensure a quadratic rate of convergence. The efficacy of the presented algorithm, and especially that of the hybrid formulation is demonstrated with the help of numerical examples.

  11. Facile synthesis of gradient mesoporous carbon monolith based on polymerization-induced phase separation

    Science.gov (United States)

    Xu, Shunjian; Luo, Yufeng; Zhong, Wei; Xiao, Zonghu; Luo, Yongping; Ou, Hui; Zhao, Xing-Zhong

    2014-06-01

    In this paper, a gradient mesoporous carbon (GMC) monolith derived from the mixtures of phenolic resin (PF) and ethylene glycol (EG) was prepared by a facile route based on polymerization-induced phase separation under temperature gradient (TG). A graded biphasic structure of PF-rich and EG-rich phases was first formed in preform under a TG, and then the preform was pyrolyzed to obtain the GMC monolith. The TG is mainly induced by the thermal resistance of the preferential phase separation layer at high temperature region. The pore structure of the monolith changes gradually along the TG direction. When the TG varies from 58°C to 29°C, the pore size, apparent porosity and specific surface area of the monolith range respectively from 18 nm to 83 nm, from 32% to 39% and from 140.5 m2/g to 515.3 m2/g. The gradient porous structure of the monolith is inherited from that of the preform, which depends on phase separation under TG in the resin mixtures. The pyrolysis mainly brings about the contraction of the pore size and wall thickness as well as the transformation of polymerized PF into glassy carbon.

  12. Advanced digital modulation: Communication techniques and monolithic GaAs technology

    Science.gov (United States)

    Wilson, S. G.; Oliver, J. D., Jr.; Kot, R. C.; Richards, C. R.

    1983-01-01

    Communications theory and practice are merged with state-of-the-art technology in IC fabrication, especially monolithic GaAs technology, to examine the general feasibility of a number of advanced technology digital transmission systems. Satellite-channel models with (1) superior throughput, perhaps 2 Gbps; (2) attractive weight and cost; and (3) high RF power and spectrum efficiency are discussed. Transmission techniques possessing reasonably simple architectures capable of monolithic fabrication at high speeds were surveyed. This included a review of amplitude/phase shift keying (APSK) techniques and the continuous-phase-modulation (CPM) methods, of which MSK represents the simplest case.

  13. Fabrication of Monolithic Dye-Sensitized Solar Cell Using Ionic Liquid Electrolyte

    Directory of Open Access Journals (Sweden)

    Seigo Ito

    2012-01-01

    Full Text Available To improve the durability of dye-sensitized solar cells (DSCs, monolithic DSCs with ionic liquid electrolyte were studied. Deposited by screen printing, a carbon layer was successfully fabricated that did not crack or peel when annealing was employed beforehand. Optimized electrodes exhibited photovoltaic characteristics of 0.608 V open-circuit voltage, 6.90 cm−2 mA short-circuit current, and 0.491 fill factor, yielding 2.06% power conversion efficiency. The monolithic DSC using ionic liquid electrolyte was thermally durable and operated stably for 1000 h at 80°C.

  14. Long all-active monolithic mode-locked lasers with surface-etched bragg gratings

    OpenAIRE

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4-mm-long monolithic InAlGaAsP–InP mode-locked lasers with integrated deeply surface etched distributed Bragg reflector (DBR) mirrors. The lasers produce 3.7-ps transform-limited Gaussian pulses with 10-mW average output power and 250-fs absolute timing jitter. The performance of the DBR lasers is compared to the performance of Fabry–PÉrot mode-locked lasers from the same wafer and to the performance of earlier reported long monolithic DBR mode-locked lasers and is found ...

  15. Long all-active monolithic mode-locked lasers with surface-etched bragg gratings

    DEFF Research Database (Denmark)

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4-mm-long monolithic InAlGaAsP–InP mode-locked lasers with integrated deeply surface etched distributed Bragg reflector (DBR) mirrors. The lasers produce 3.7-ps transform-limited Gaussian pulses with 10-mW average output power and 250-fs absolute timing jitter. The performance...... of the DBR lasers is compared to the performance of Fabry–PÉrot mode-locked lasers from the same wafer and to the performance of earlier reported long monolithic DBR mode-locked lasers and is found to be better....

  16. Rebalancing interests and power structures on crowdworking platforms

    Directory of Open Access Journals (Sweden)

    Ayad Al-Ani

    2016-06-01

    Full Text Available Crowdwork on virtual platforms is developing into a recognisable employment and business model on the internet. Despite their many differences, the platforms that have emerged over the last few years have one thing in common: a crowd of individual producers and capabilities is mobilised – in the form of labour, accommodation or durable goods – onto the market in cooperation and competition with firms from traditional industries. This study analyses the factors crowdworkers consider relevant in their work and the measures they view as helpful in improving their working relationship with platforms. It is apparent that, in the best tradition of the peer economy, this new type of worker still considers learning and fun important factors for his or her engagement. Despite these effectively intrinsic factors, workers are quite aware of their situation, which does not put them on equal terms with the platform’s algorithms and customer focus. This awareness of power disparities does not lead them, however, to reconsider their effectiveness when it comes to renegotiating terms with the platform: when specifically asked about the role of unions, the majority of crowdworkers did not expect help in self-organisation from these institutions. Considering the difficulties in regulating the market for platforms, (self- organisation of crowdworkers, however, is an important prerequisite in rebalancing the power structure dominated by platform owners and their customers. Self-organisation is something digital natives are quite familiar with and we have to assume that crowdworkers are perhaps overconfident in their abilities. And due to the novelty of this industry, this confidence has not been shaken yet by labour disputes or even by growing dissatisfaction with platforms.

  17. Components for monolithic fiber chirped pulse amplification laser systems

    Science.gov (United States)

    Swan, Michael Craig

    The first portion of this work develops techniques for generating femtosecond-pulses from conventional fabry-perot laser diodes using nonlinear-spectral-broadening techniques in Yb-doped positive dispersion fiber ampliers. The approach employed an injection-locked fabry-perot laser diode followed by two stages of nonlinear-spectral-broadening to generate sub-200fs pulses. This thesis demonstrated that a 60ps gain-switched fabry-perot laser-diode can be injection-locked to generate a single-longitudinal-mode pulse and compressed by nonlinear spectral broadening to 4ps. Two problems have been identified that must be resolved before moving forward with this approach. First, gain-switched pulses from a standard diode-laser have a number of characteristics not well suited for producing clean self-phase-modulation-broadened pulses, such as an asymmetric temporal shape, which has a long pulse tail. Second, though parabolic pulse formation occurs for any arbitrary temporal input pulse profile, deviation from the optimum parabolic input results in extensively spectrally modulated self-phase-modulation-broadened pulses. In conclusion, the approach of generating self-phase-modulation-broadened pulses from pulsed laser diodes has to be modified from the initial approach explored in this thesis. The first Yb-doped chirally-coupled-core ber based systems are demonstrated and characterized in the second portion of this work. Robust single-mode performance independent of excitation or any other external mode management techniques have been demonstrated in Yb-doped chirally-coupled-core fibers. Gain and power efficiency characteristics are not compromised in any way in this novel fiber structure up to the 87W maximum power achieved. Both the small signal gain at 1064nm of 30.3dB, and the wavelength dependence of the small signal gain were comparable to currently deployed large-mode-area-fiber technology. The efficiencies of the laser and amplifier were measured to be 75% and 54

  18. Monolithic integration of an (Al)GaAs laser and an intracavity electroabsorption modulator using selective partial interdiffusion

    Science.gov (United States)

    O'Brien, S.; Shealy, J. R.; Wicks, G. W.

    1991-04-01

    The monolithic integration of an intracavity modulator with a multiple quantum well (Al)GaAs laser has been accomplished with the use of selective partial interdiffusion. Interdiffusion was used to create a blue-shifted and semitransparent modulator section in a ridge laser structure. In measuring the total optical output power from the devices, steady-state extinction ratios of 20 dB were measured at reverse biases of -4.6 and -3.6 V for modulator sections with lengths of 200 and 400 microns, respectively. Shifting of the lasing mode toward longer wavelengths was also observed making the structure useful as a tunable device and for frequency modulation applications.

  19. Purification of Astaxanthin from Laminariajaponica by Ionic Liquid-based Monolithic Cartridge

    Institute of Scientific and Technical Information of China (English)

    YOON Chang-hwan; ZHU Tao; ROW Kyung-ho

    2012-01-01

    An effective and accurate method was developed for the extraction of astaxanthin from Laminariajaponica with subsequent separation by ionic liquid-based monolithic cartridge.The optimized extraction conditions including extraction solvent(ethanol),extraction time(90 min) and ultrasonic power(75 W) were obtained by systematical investigation.Chromatographic analysis was performed on a C18 column with ultraviolet(UV) detection at 476nm,and a solution consisting of methanol/acetonitrile/H20/dichloromethane(83:6:6:5,volume ratio) was used as the mobile phase at a flow rate of 0.7 mL/min.After ionic liquid-based monolithic solid phase extraction,17.82 μg/g astaxanthin was obtained from Laminariajaponica.This ionic liquid-based monolithic cartridge exhibits high affinity and selectivity for astaxanthin,and it can be potentially used as the stationary phase of high performance liquid chromatography( HPLC).

  20. A monolithic integrated micro direct methanol fuel cell based on sulfo functionalized porous silicon

    Science.gov (United States)

    Wang, M.; Lu, Y. X.; Liu, L. T.; Wang, X. H.

    2016-11-01

    In this paper, we demonstrate a monolithic integrated micro direct methanol fuel cell (μDMFC) for the first time. The monolithic integrated μDMFC combines proton exchange membrane (PEM) and Pt nanocatalysts, in which PEM is achieved by the functionalized porous silicon membrane and 3D Pt nanoflowers being synthesized in situ on it as catalysts. Sulfo groups functionalized porous silicon membrane serves as a PEM and a catalyst support simultaneously. The μDMFC prototype achieves an open circuit voltage of 0.3 V, a maximum power density of 5.5 mW/cm2. The monolithic integrated μDMFC offers several desirable features such as compatibility with micro fabrication techniques, an undeformable solid PEM and the convenience of assembly.

  1. Assessment of the Grouted IXC Monolith in Support of K East Basin Hazard Categorization

    Energy Technology Data Exchange (ETDEWEB)

    Short, Steven M.; Dodson, Michael G.; Alzheimer, James M.; Meyer, Perry A.

    2007-10-12

    Addendum to original report updating the structural analysis of the I-beam accident to reflect a smaller I-beam than originally assumed (addendum is 2 pages). The K East Basin currently contains six ion exchange columns (IXCs) that were removed from service over 10 years ago. Fluor Hanford plans to immobilize the six ion exchange columns (IXCs) in place in a concrete monolith. PNNL performed a structural assessment of the concrete monolith to determine its capability to absorb the forces imposed by postulated accidents and protect the IXCs from damage and thus prevent a release of radioactive material. From this assessment, design specifications for the concrete monolith were identified that would prevent a release of radioactive material for any of the postulated hazardous conditions.

  2. Feasibility evaluation of the monolithic braided ablative nozzle

    Science.gov (United States)

    Director, Mark N.; McPherson, Douglass J., Sr.

    1992-02-01

    The feasibility of the monolithic braided ablative nozzle was evaluated as part of an independent research and development (IR&D) program complementary to the National Aeronautics and Space Administration/Marshall Space Flight Center (NASA/MSFC) Low-Cost, High-Reliability Case, Insulation and Nozzle for Large Solid Rocket Motors (LOCCIN) Program. The monolithic braided ablative nozzle is a new concept that utilizes a continuous, ablative, monolithic flame surface that extends from the nozzle entrance, through the throat, to the exit plane. The flame surface is fabricated using a Through-the-Thickness braided carbon-fiber preform, which is impregnated with a phenolic or phenolic-like resin. During operation, the braided-carbon fiber/resin material ablates, leaving the structural backside at temperatures which are sufficiently low to preclude the need for any additional insulative materials. The monolithic braided nozzle derives its potential for low life cycle cost through the use of automated processing, one-component fabrication, low material scrap, low process scrap, inexpensive raw materials, and simplified case attachment. It also has the potential for high reliability because its construction prevents delamination, has no nozzle bondlines or leak paths along the flame surface, is amenable to simplified analysis, and is readily inspectable. In addition, the braided construction has inherent toughness and is damage-tolerant. Two static-firing tests were conducted using subscale, 1.8 - 2.0-inch throat diameter, hardware. Tests were approximately 15 seconds in duration, using a conventional 18 percent aluminum/ammonium perchlorate propellant. The first of these tests evaluated the braided ablative as an integral backside insulator and exit cone; the second test evaluated the monolithic braided ablative as an integral entrance/throat/exit cone nozzle. Both tests met their objectives. Radial ablation rates at the throat were as predicted, approximately 0.017 in

  3. The Power Structure of 2-Generator 2-Groups of Class Two

    Institute of Scientific and Technical Information of China (English)

    Friedrich L. Kluempen

    2002-01-01

    In 1934, Hall introduced regular p-groups. Any regular 2-group is abelian. A regular p-group is power closed, exponent closed, strongly semi-pabelian, and an exact power margin group. The study of these properties and relationships among them constitutes the investigation of the power structure of a p-group. In this paper, we classify 2-generator 2-groups of nilpotency class two according to their power structure.

  4. Fabrication of Monolithic RERTR Fuels by Hot Isostatic Pressing

    Energy Technology Data Exchange (ETDEWEB)

    Jan-Fong Jue; Blair H. Park; Curtis R. Clark; Glenn A. Moore; Dennis D. Keiser, Jr.

    2010-11-01

    The RERTR (Reduced Enrichment for Research and Test Reactors) Program is developing advanced nuclear fuels for high-power test reactors. Monolithic fuel design provides higher uranium loading than that of the traditional dispersion fuel design. Hot isostatic pressing is a promising process for low-cost batch fabrication of monolithic RERTR fuel plates for these high-power reactors. Bonding U Mo fuel foil and 6061 Al cladding by hot isostatic press bonding was successfully developed at Idaho National Laboratory. Due to the relatively high processing temperature, the interaction between fuel meat and aluminum cladding is a concern. Two different methods were employed to mitigate this effect: (1) a diffusion barrier and (2) a doping addition to the interface. Both types of fuel plates have been fabricated by hot isostatic press bonding. Preliminary results show that the direct fuel/cladding interaction during the bonding process was eliminated by introducing a thin zirconium diffusion barrier layer between the fuel and the cladding. Fuel plates were also produced and characterized with a silicon-rich interlayer between fuel and cladding. This paper reports the recent progress of this developmental effort and identifies the areas that need further attention.

  5. Sound power radiation from a vibrating structure in terms of structure-dependent radiation modes

    Science.gov (United States)

    Ji, Lin; Bolton, J. Stuart

    2015-01-01

    As a good supplement of conventional acoustic radiation modes (a-modes), a set of so-called "structure-dependent radiation modes" (s-modes) is introduced to describe the sound power radiation from a vibrating structure. Differing from a-modes, s-modes are determined by not only the acoustic resistance matrix of the structure but also the frequency-independent normal modes of the structure. Such a new definition has the following main advantages over the conventional one: (1) it can reflect directly the influences of dynamic properties (e.g., boundary conditions) of the structures on its sound power radiation; (2) the number of s-modes generated is generally less than that of a-modes since the former depends on the number of structural modes involved in the vibration while the latter depends on the number of segmented elemental radiators of the structure, and consequently, the demand for large data storage can be greatly alleviated, especially for large structures and/or higher frequency vibrations; (3) the set of s-modes possesses a better convergence than that of a-modes because the higher ordered s-modes can decay more rapidly than the same ordered a-modes. Two baffled, finite, models, i.e., a simple beam and a thin plate, are employed to investigate numerically the acoustic properties of s-modes, and then compared with those of a-modes. It has been shown that the two sets of radiation modes share a very similar frequency-dependent behavior in that the radiation efficiency falls off very rapidly with increasing mode order at low frequency range (typically with kl<1). Meanwhile, the number of s-modes required to describe the total sound power radiation is found to be the same as that of a-modes. Consequently, an appropriate truncation of a-modes can be achieved by using the number of vibrational modes involved. Nevertheless, the odd-ordered (even-ordered) s-modes are found only associated with the odd-numbered (even-ordered) structural modes. In case of only few

  6. Preparation and characterization of poly-(methacrylatoethyl trimethylammonium chloride-co-vinylbenzyl chloride-co-ethylene dimethacrylate monolith

    Directory of Open Access Journals (Sweden)

    Eko Malis

    2015-05-01

    Full Text Available A polymer monolithic column, poly-(methacrylatoethyltrimethylammonium chloride-co-vinylbenzyl chloride-co-ethylene dimethacrylate or poly-(MATE-co-VBC-co-EDMA was successfully prepared in the current study by one-step thermally initiated in situ polymerization, confined in a steel tubing of 0.5 mm i.d. and 1/16” o.d. The monoliths were prepared from methacrylatoethyltrimethylammonium chloride (MATE and vinylbenzyl chloride (VBC as monomer and ethylene dimethacrylate (EDMA as crosslinker using a binary porogen system of 1-propanol and 1,4-butanediol. The inner wall of steel tubing was pretreated with 3-methacryloxypropyl-trimethoxysilane (MAPS. In order to obtain monolith with adequate column efficiency and low flow resistance, some parameters such as total monomer concentration (%T and crosslinker concentration (%C were optimized. The morphology of this monolith was assessed by scanning electron microscopy (SEM. The properties of the monolithic column, such as permeability, binding capacity, and pore size distribution were also characterized in detail. From the results of the characterization of all monolith variation, monolith with %T 30 %C 50 and %T 35 %C 50 give the best characteristic. These monoliths have high permeability, adequate molecular recognition sites (represented with binding capacity value of over 20 mg/mL, and have over 80% flow through pores in their pore structure contribute to low flow resistance. The resulted monolithic columns have promising potential for dual mode liquid chromatography. MATE may contribute for anion-exchange while VBC may responsible for reversed-phase liquid chromatography.

  7. Development of monolith Nd:YAG /Cr+4:YAG passively Q-switched microchip laser

    Science.gov (United States)

    Izhnin, Ihor; Vakiv, Mykola; Izhnin, Aleksandr; Syvorotka, Igor; Ubizskii, Sergii; Syvorotka, Ihor, Jr.

    2005-09-01

    The main features of passively Q-switched microchip lasers development are considered. The active medium of laser is an epitaxial structure combining an epitaxial layer of saturable absorber Cr4+:Y3Al5O12 (Cr:YAG) grown on substrate of generating crystal Nd:YAG by liquid phase epitaxy. The modulator layer has an initial optical absorption of 36 cm-1 at wavelength of lasing (1064 nm). The epitaxial layer grown on unworking side was mechanically removed and this substrate side was optically polished. The other one was processed precisely to needed thickness. The cavity's mirrors were deposited by electron beam technique directly on each side of the structure to form a rugged, monolithic resonator. Diode laser Model ATC-C4000 with lasing wavelength 808 nm provided the CW end pumping. The output pulses parameters were investigated by means of test bench consisting of photoelectric transducer FEK-15 and Digital Phosphor Oscilloscope TDS 5052B. The obtained laser parameter are as follows: pulse width (FWHM) about 1.3 ns, repetition rate 5.5 kHz, average output power about 10 mW, pulse energy 1.0 μJ, pick power 1.2 kW. The possible solutions for laser parameter improving and optimization are discussed.

  8. Efficient adsorbents of nanoporous aluminosilicate monoliths for organic dyes from aqueous solution.

    Science.gov (United States)

    El-Safty, Sherif A; Shahat, Ahmed; Awual, Md Rabiul

    2011-07-01

    Growing public awareness on the potential risk to humans of toxic chemicals in the environment has generated demand for new and improved methods for toxicity assessment and removal, rational means for health risk estimation. With the aim of controlling nanoscale adsorbents for functionality in molecular sieving of organic pollutants, we fabricated cubic Im3m mesocages with uniform entrance and large cavity pores of aluminosilicates as highly promising candidates for the colorimetric monitoring of organic dyes in an aqueous solution. However, a feasible control over engineering of three-dimensional (3D) mesopore cage structures with uniform entrance (~5 nm) and large cavity (~10 nm) allowed the development of nanoadsorbent membranes as a powerful tool for large-quantity and high-speed (in minutes) adsorption/removal of bulk molecules such as organic dyes. Incorporation of high aluminum contents (Si/Al=1) into 3D cubic Im3m cage mesoporous silica monoliths resulted in small, easy-to-use optical adsorbent strips. In such adsorption systems, natural surfaces of active acid sites of aluminosilicate strips strongly induced both physical adsorption of chemically responsive dyes and intraparticle diffusion into cubic Im3m mesocage monoliths. Results likewise indicated that although aluminosilicate strips with low Si/Al ratios exhibit distortion in pore ordering and decrease in surface area and pore volume, enhancement of both molecular converges and intraparticle diffusion onto the network surfaces and into the pore architectures of adsorbent membranes was achieved. Moreover, 3D mesopore cage adsorbents are reversible, offering potential for multiple adsorption assays.

  9. Evaluation of Coordinate Compensator Structure Based on Power Injection Model for Loading Margin Enhancement in Power Systems

    Directory of Open Access Journals (Sweden)

    Reza Sedaghati

    2013-09-01

    Full Text Available In this paper, the structure of Hybrid Power Flow Controller (HPFC is proposed in order to improve static voltage stability characteristics. HPFC forms a hybrid controller using IPFC series converters as a hybrid with existing parallel and passive compensator (SVC in power system. Utilization of hybrid structures makes it possible to use converters for improving performance of both old and existing compensators in power networks. In this study, the power injection model (PIM is used to model the hybrid power flow controller in Newton load flow. The aforementioned model is simulated in MATLAB software. The P-V curves of PQ buses of a typical system are evaluated by a continuous power flow (CPF method to analyses the effect of this controller on static voltage stability characteristics. Meanwhile, SVC as existing devices in the system and UPFC and IPFC as state-of-the-art compensator devices are compared with the proposed hybrid structure. The amount of active and reactive power loss and improvement of loading limit of the system are used as main parameters in our comparison.

  10. 1060-nm Tunable Monolithic High Index Contrast Subwavelength Grating VCSEL

    DEFF Research Database (Denmark)

    Ansbæk, Thor; Chung, Il-Sug; Semenova, Elizaveta

    2013-01-01

    We present the first tunable vertical-cavity surface-emitting laser (VCSEL) where the top distributed Bragg reflector has been completely substituted by an air-cladded high-index-contrast subwavelength grating (HCG) mirror. In this way, an extended cavity design can be realized by reducing...... the reflection at the semiconductor #x2013;air interface using an anti-reflective coating (ARC). We demonstrate how the ARC can be integrated in a monolithic structure by oxidizing AlGaAs with high Al-content. The HCG VCSEL has the potential to achieve polarization stable single-mode output with high tuning...

  11. Chiral monolithic absorbent constructed by optically active helical-substituted polyacetylene and graphene oxide: preparation and chiral absorption capacity.

    Science.gov (United States)

    Li, Weifei; Wang, Bo; Yang, Wantai; Deng, Jianping

    2015-02-01

    Chiral monolithic absorbent is successfully constructed for the first time by using optically active helical-substituted polyacetylene and graphene oxide (GO). The preparative strategy is facile and straightforward, in which chiral-substituted acetylene monomer (Ma), cross-linker (Mb), and alkynylated GO (Mc) undergo copolymerization to form the desired monolithic absorbent in quantitative yield. The resulting monoliths are characterized by circular dichroism, UV-vis absorption, scanning electron microscopy (SEM), FT-IR, Raman, energy-dispersive spectrometer (EDS), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), XPS, and thermogravimetric analysis (TGA) techniques. The polymer chains derived from Ma form chiral helical structures and thus provide optical activity to the monoliths, while GO sheets contribute to the formation of porous structures. The porous structure enables the monolithic absorbents to demonstrate a large swelling ratio in organic solvents, and more remarkably, the helical polymer chains provide optical activity and further enantio-differentiating absorption ability. The present study establishes an efficient and versatile methodology for preparing novel functional materials, in particular monolithic chiral materials based on substituted polyacetylene and GO.

  12. Demonstrating Structural Adequacy of Nuclear Power Plant Containment Structures for Beyond Design-Basis Pressure Loadings

    Energy Technology Data Exchange (ETDEWEB)

    Braverman, J.I.; Morante, R.

    2010-07-18

    ABSTRACT Demonstrating the structural integrity of U.S. nuclear power plant (NPP) containment structures, for beyond design-basis internal pressure loadings, is necessary to satisfy Nuclear Regulatory Commission (NRC) requirements and performance goals. This paper discusses methods for demonstrating the structural adequacy of the containment for beyond design-basis pressure loadings. Three distinct evaluations are addressed: (1) estimating the ultimate pressure capacity of the containment structure (10 CFR 50 and US NRC Standard Review Plan, Section 3.8) ; (2) demonstrating the structural adequacy of the containment subjected to pressure loadings associated with combustible gas generation (10 CFR 52 and 10 CFR 50); and (3) demonstrating the containment structural integrity for severe accidents (10 CFR 52 as well as SECY 90-016, SECY 93-087, and related NRC staff requirements memoranda (SRMs)). The paper describes the technical basis for specific aspects of the methods presented. It also presents examples of past issues identified in licensing activities related to these evaluations.

  13. Reprocessing of LEU U-Mo Dispersion and Monolithic Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Vandegrift, G.F.; Jerden, J.; Stepinski, D.C.; Figueroa, J.; Williamson, M.A.; Kleeck, M.A. Van; Blaskovitz, R.J.; Ziegler, A.J.; Maggos, L.E.; Swanson, J.; Fortner, J.; Bakel, A.J. [Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, IL 60439 (United States)

    2011-07-01

    For conversion of high-performance research reactors from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel, a fuel material with a higher density than uranium aluminide is required. Development studies are underway to develop U-Mo dispersion and monolithic fuels for conversion of several high- performance reactors. For dispersion fuels, development is narrowing down to a composition of U-7Mo dispersed in an aluminium matrix containing {approx}5% silicon. For monolithic fuels to be used in high performance research reactors in the United States, a zirconium-bonded U-10Mo foil appears to be the fuel of choice. For conversion to be realized a back-end disposition path is required for both fuels; one disposition pathway is reprocessing. Argonne National Laboratory is developing a pyroprocess for reprocessing spent monolithic fuel. Pyroprocessing was chosen over conventional aqueous solvent extraction due to the necessity of adding fluoride to the fuel-dissolution solution in order to dissolve the zirconium bonding layer on the U-Mo fuel. The proposed flowsheet and development activities will be described. A literature survey points to the ability to reprocess U-Mo dispersion fuels by an aqueous process, but due to several special characteristics of the fuel, the solvent-extraction flowsheets will be a departure from that normally used for the reprocessing of power reactor fuel. Special concerns that must be addressed in reprocessing these fuels are, for example, the low solubilities of uranyl molybdate, molybdic acid, and silicic acid in nitric acid solutions. This paper will address these concerns and development activities required to overcome them. (author)

  14. Modified monolithic silica capillary for preconcentration of catecholamines

    Institute of Scientific and Technical Information of China (English)

    Wei Chang; Tusyo-shi Komazu

    2009-01-01

    Preconcentration of catecholamines by the modified monolithic silica in the capillary was investigated in this study. In order to achieve a microchip-based method for determining catecholamines in the saliva, the monolithic silica was fabricated in the capillary and the monolithic silica was chemically modified by on-column reaction with phenylboronate. Different modified methods were compared. The concentration conditions were optimized. This study indicates the applicability of the modified monolithic silica capillary when it was used to concentrate catecholamines.

  15. Modified monolithic silica capillary for preconcentration of catecholamines

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Preconcentration of catecholamines by the modified monolithic silica in the capillary was investigated in this study. In order to achieve a microchip-based method for determining catecholamines in the saliva,the monolithic silica was fabricated in the capillary and the monolithic silica was chemically modified by on-column reaction with phenylboronate. Different modified methods were compared. The concentration conditions were optimized. This study indicates the applicability of the modified monolithic sili...

  16. Fracture resistance of monolithic zirconia molar crowns with reduced thickness

    OpenAIRE

    Nakamura, Keisuke; Harada, A.; Inagaki, R.; Kanno, Taro; Niwano, Y; Milleding, Percy; Ørtengren, Ulf Thore

    2015-01-01

    This is the accepted manuscript version. Published version is available at Acta Odontologica Scandinavica Objectives. The purpose of the present study was to analyze the relationship between fracture load of monolithic zirconia crowns and axial/occlusal thickness, and to evaluate the fracture resistance of monolithic zirconia crowns with reduced thickness in comparison with that of monolithic lithium disilicate crowns with regular thickness. Materials and methods. Monolithic zi...

  17. Surface characteristics and antibacterial activity of a silver-doped carbon monolith

    Directory of Open Access Journals (Sweden)

    Marija Vukčević et al

    2008-01-01

    Full Text Available A carbon monolith with a silver coating was prepared and its antimicrobial behaviour in a flow system was examined. The functional groups on the surface of the carbon monolith were determined by temperature-programmed desorption and Boehm's method, and the point of zero charge was determined by mass titration. The specific surface area was examined by N2 adsorption using the Brunauer, Emmett and Teller (BET method. As a test for the surface activity, the deposition of silver from an aqueous solution of a silver salt was used. The morphology and structure of the silver coatings were characterized by scanning electron microscopy and x-ray diffraction. The resistance to the attrition of the silver deposited on the carbon monolith was tested. The antimicrobial activity of the carbon monolith with a silver coating was determined using standard microbiological methods. Carbon monolith samples with a silver coating showed good antimicrobial activity against Escherichia coli, Staphylococcus aureus and Candida albicans, and are therefore suitable for water purification, particularly as personal disposable water filters with a limited capacity.

  18. Development of an epoxy-based monolith used for the affinity capturing of Escherichia coli bacteria.

    Science.gov (United States)

    Peskoller, Caroline; Niessner, Reinhard; Seidel, Michael

    2009-05-01

    An epoxy-based monolith has been developed for use as hydrophilic support in bioseparation. This monolith is produced by self-polymerization of polyglycerol-3-glycidyl ether in organic solvents as porogens at room temperature within 1 h. One receives a highly cross-linked structure that provides useful mechanical properties. The porosity and pore diameter can be controlled by varying the composition of the porogen. In this work, an epoxy-based monolith with a high porosity (79%) and large pore size (22 microm) is prepared and used in affinity capturing of bacterial cells. These features allow the passage of bacterial cells through the column. As affinity ligand polymyxin B is used, which allows the binding of gram-negative bacteria. The efficiency of the monolithic affinity column is studied with Escherichia coli spiked in water. Bacterial cells are concentrated on the column at pH 4 and eluted with a recovery of 97+/-3% in 200 microL by changing the pH value without impairing viability of bacteria. The dynamic capacity for the monolithic column is nearly independent of the flow rate (4x10(9)cells/column). Thereby, it is possible to separate and enrich gram-negative bacterial cells, such as E. coli, with high flow rates (10 mL/min) and low back pressure (<1 bar) in a volume as low as 200 microL compatible for real-time polymerase chain reaction, microarray formats, and biosensors.

  19. Fabrication of Porous Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate Monoliths via Thermally Induced Phase Separation

    Directory of Open Access Journals (Sweden)

    Takashi Tsujimoto

    2016-02-01

    Full Text Available This study deals with the fabrication of biodegradable porous materials from bacterial polyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate (P3HB3HHx, via thermally induced phase separation. P3HB3HHx monoliths with topological porous structure were prepared by dissolution of P3HB3HHx in dimethyl sulfoxide (DMSO at 85 °C and subsequent quenching. The microstructure of the resulting P3HB3HHx monoliths was changed by the P3HB3HHx concentration of the polymer solution. Differential scanning calorimetry and polarized optical microscope analysis revealed that the P3HB3HHx monoliths crystallized during phase separation and the subsequent aging. The mechanical properties, such as compression modulus and stress, of the monoliths depended on the 3-hydroxyhexanoate content of P3HB3HHx. Furthermore, the P3HB3HHx monolith absorbed linseed oil in preference to water in a plant oil–water mixture. In combination with the biodegradable character of P3HB3HHx, the present study is expected to contribute to the development of bio-based materials.

  20. One-pot preparation of a novel monolith for high performance liquid chromatography applications.

    Science.gov (United States)

    Jiao, Xiaoyan; Shen, Shigang; Shi, Tiesheng

    2015-12-15

    Various novel porous organic-based monoliths with the mode of hydrophobicity were synthesized by in situ free-radical crosslinking copolymerization and optimized for the separations of small molecules and high-performance reversed-phase chromatography (RP-chromatography). These monoliths contained co-polymers based on glycidyl methacrylate (GMA)/ethylene glycol dimethacrylate (EDMA)/tripropylene glycol diacrylate (TPGDA) or EDMA/TPGDA. A mixture of cetanol, methanol and poly (ethylene glycol) (PEG) was used as the porogen, with the ratio of these solvents being varied along with the polymerization temperature to generate a library of monoliths. The conditions were optimized and the resulting poly (GMA-co-TPGDA-co-EDMA) monolith was investigated by infrared spectrometer (IR), field emission scanning electron microscope (FESEM), and mercury intrusion porosimetry (MIP), respectively. The column performance was assessed by the separation of a series of neutral solutes of benzene derivatives. The result demonstrated that the prepared monolith exhibited an RP-chromatographic behavior and relatively homogeneous structure, good permeability and separation performance. Moreover, the relative standard deviations (RSDs) of the retention factor values for benzene derivatives were less than 1.5% (n=7, column-to-column). The approach used in this study was extended to the separation of anilines.

  1. Characterization of polymer monoliths containing embedded nanoparticles by scanning transmission X-ray microscopy (STXM).

    Science.gov (United States)

    Arrua, R Dario; Hitchcock, Adam P; Hon, Wei Boon; West, Marcia; Hilder, Emily F

    2014-03-18

    The structural and chemical homogeneity of monolithic columns is a key parameter for high efficiency stationary phases in liquid chromatography. Improved characterization techniques are needed to better understand the polymer morphology and its optimization. Here the analysis of polymer monoliths by scanning transmission X-ray microscopy (STXM) is presented for the first time. Poly(butyl methacrylate-co-ethyleneglycoldimethacrylate) [poly(BuMA-co-EDMA)] monoliths containing encapsulated divinylbenzene (DVB) nanoparticles were characterized by STXM, which gives a comprehensive, quantitative chemical analysis of the monolith at a spatial resolution of 30 nm. The results are compared with other methods commonly used for the characterization of polymer monoliths [scanning electron microscopy (SEM), transmission electron microscopy (TEM), mercury porosimetry, and nitrogen adsorption]. The technique permitted chemical identification and mapping of the nanoparticles within the polymeric scaffold. Residual surfactant, which was used during the manufacture of the nanoparticles, was also detected. We show that STXM can give more in-depth chemical information for these types of materials and therefore lead to a better understanding of the link between polymer morphology and chromatographic performance.

  2. Eigenpolarization theory of monolithic nonplanar ring oscillators

    Science.gov (United States)

    Nilsson, Alan C.; Gustafson, Eric K.; Byer, Robert L.

    1989-01-01

    Diode-laser-pumped monolithic nonplanar ring oscillators (NPROs) in an applied magnetic field can operate as unidirectional traveling-wave lasers. The diode laser pumping, monolithic construction, and unidirectional oscillation lead to narrow linewidth radiation. Here, a comprehensive theory of the eigenpolarizations of a monolithic NPRO is presented. It is shown how the properties of the integral optical diode that forces unidirectional operation depend on the choice of the gain medium, the applied magnetic field, the output coupler, and the geometry of the nonplanar ring light path. Using optical equivalence theorems to gain insight into the polarization characteristics of the NPRO, a strategy for designing NPROs with low thresholds and large loss nonreciprocities is given. An analysis of the eigenpolarizations for one such NPRO is presented, alternative optimization approaches are considered, and the prospects for further reducing the linewidths of these lasers are briefly discussed.

  3. Physical and chemical sensing using monolithic semiconductor optical transducers

    Science.gov (United States)

    Zappe, Hans P.; Hofstetter, Daniel; Maisenhoelder, Bernd; Moser, Michael; Riel, Peter; Kunz, Rino E.

    1997-09-01

    We present two monolithically integrated optical sensor systems based on semiconductor photonic integrated circuits. These compact, robust and highly functional transducers perform all necessary optical and electro-optical functions on-chip; extension to multi-sensor arrays is easily envisaged. A monolithic Michelson interferometer for high-resolution displacement measurement and a monolithic Mach-Zehnder interferometer for refractometry are discussed.

  4. Monolithic carbide-derived carbon films for micro-supercapacitors.

    Science.gov (United States)

    Chmiola, John; Largeot, Celine; Taberna, Pierre-Louis; Simon, Patrice; Gogotsi, Yury

    2010-04-23

    Microbatteries with dimensions of tens to hundreds of micrometers that are produced by common microfabrication techniques are poised to provide integration of power sources onto electronic devices, but they still suffer from poor cycle lifetime, as well as power and temperature range of operation issues that are alleviated with the use of supercapacitors. There have been a few reports on thin-film and other micro-supercapacitors, but they are either too thin to provide sufficient energy or the technology is not scalable. By etching supercapacitor electrodes into conductive titanium carbide substrates, we demonstrate that monolithic carbon films lead to a volumetric capacity exceeding that of micro- and macroscale supercapacitors reported thus far, by a factor of 2. This study also provides the framework for integration of high-performance micro-supercapacitors onto a variety of devices.

  5. Characterization of CIM monoliths as enzyme reactors.

    Science.gov (United States)

    Vodopivec, Martina; Podgornik, Ales; Berovic, Marin; Strancar, Ales

    2003-09-25

    The immobilization of the enzymes citrate lyase, malate dehydrogenase, isocitrate dehydrogenase and lactate dehydrogenase to CIM monolithic supports was performed. The long-term stability, reproducibility, and linear response range of the immobilized enzyme reactors were investigated along with the determination of the kinetic behavior of the enzymes immobilized on the CIM monoliths. The Michaelis-Menten constant K(m) and the turnover number k(3) of the immobilized enzymes were found to be flow-unaffected. Furthermore, the K(m) values of the soluble and immobilized enzyme were found to be comparable. Both facts indicate the absence of a diffusional limitation in immobilized CIM enzyme reactors.

  6. Monolithically integrated optoelectronic down-converter (MIOD)

    Science.gov (United States)

    Portnoi, Efrim L.; Venus, G. B.; Khazan, A. A.; Gorfinkel, Vera B.; Kompa, Guenter; Avrutin, Evgenii A.; Thayne, Iain G.; Barrow, David A.; Marsh, John H.

    1995-06-01

    Optoelectronic down-conversion of very high-frequency amplitude-modulated signals using a semiconductor laser simultaneously as a local oscillator and a mixer is proposed. Three possible constructions of a monolithically integrated down-converter are considered theoretically: a four-terminal semiconductor laser with dual pumping current/modal gain control, and both a passively mode-locked and a passively Q-switched semiconductor laser monolithically integrated with an electroabsorption or pumping current modulator. Experimental verification of the feasibility of the concept of down conversion in a laser diode is presented.

  7. Separation of Immunoglobulin in Conjunction with High Performance Liquid Chromatography Using Poly(vinyl ester resin) Monolith

    Institute of Scientific and Technical Information of China (English)

    YANG,Guanqun; YANG,Gengliang; LIU,Haiyan; BAI,Ligai; FENG,Xiaojuan; YANG,Xinru

    2009-01-01

    Using vinyl ester resin both as the monomer and the crosslinker,2,2-azobis(2-methylpropionitrile) (AIBN) as initiator,poly(vinyl ester resin) monolithic column was prepared to separate the immunoglobulin G (lgG) and yolk of eggs (lgY) from human plasma and egg yolk by HPLC respectively.The influence of concentration and pH of mobile phase on the chromatographic performance was investigated.Scanning electron microcopy showed that the poly(vinyl ester resin) monolithic stationary phase had a through-pore structure.Dynamic capacity of IgG on the polymeric monolithic column was investigated.The monolithic column had good flow-through properties and high resolution.The maximum adsorptive amount of IgG was 144 μg·g-1.

  8. High-density 3D graphene-based monolith and related materials, methods, and devices

    Energy Technology Data Exchange (ETDEWEB)

    Worsley, Marcus A.; Baumann, Theodore F.; Biener, Juergen; Charnvanichborikarn, Supakit; Kucheyev, Sergei; Montalvo, Elizabeth; Shin, Swanee; Tylski, Elijah

    2017-03-21

    A composition comprising at least one high-density graphene-based monolith, said monolith comprising a three-dimensional structure of graphene sheets crosslinked by covalent carbon bonds and having a density of at least 0.1 g/cm.sup.3. Also provided is a method comprising: preparing a reaction mixture comprising a suspension and at least one catalyst, said suspension selected from a graphene oxide (GO) suspension and a carbon nanotube suspension; curing the reaction mixture to produce a wet gel; drying the wet gel to produce a dry gel, said drying step is substantially free of supercritical drying and freeze drying; and pyrolyzing the dry gel to produce a high-density graphene-based monolith. Exceptional combinations of properties are achieved including high conductive and mechanical properties.

  9. Macroporous glass monoliths prepared from powdered niobium phosphate glass by fast sintering

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda Mauricio, Vitor; Alves, Oswaldo Luiz; Odone Mazali, Italo, E-mail: mazali@iqm.unicamp.br

    2011-03-15

    Macroporous monoliths were prepared by very fast sintering (between 3 and 15 min) of niobophosphate glass powders at low temperature (1018 K) using cellulose as a foaming agent. The porous materials were analyzed by thermal analysis, Raman spectroscopy, scanning electron microscopy and powder X-ray diffraction, and further investigated using X-ray microtomography, a non-destructive technique capable of reconstructing three-dimensional models of samples and providing structural measurements. The progression of the porosity of the monoliths depends on the sintering time (3 to 15 min) and the amount (up to 50% in mass) of cellulose used. The macroporous glass monoliths may find application in integrated chemical systems and in filtering processes.

  10. High-density 3D graphene-based monolith and related materials, methods, and devices

    Science.gov (United States)

    Worsley, Marcus A.; Baumann, Theodore F.; Biener, Juergen; Charnvanichborikarn, Supakit; Kucheyev, Sergei; Montalvo, Elizabeth; Shin, Swanee; Tylski, Elijah

    2017-03-21

    A composition comprising at least one high-density graphene-based monolith, said monolith comprising a three-dimensional structure of graphene sheets crosslinked by covalent carbon bonds and having a density of at least 0.1 g/cm.sup.3. Also provided is a method comprising: preparing a reaction mixture comprising a suspension and at least one catalyst, said suspension selected from a graphene oxide (GO) suspension and a carbon nanotube suspension; curing the reaction mixture to produce a wet gel; drying the wet gel to produce a dry gel, said drying step is substantially free of supercritical drying and freeze drying; and pyrolyzing the dry gel to produce a high-density graphene-based monolith. Exceptional combinations of properties are achieved including high conductive and mechanical properties.

  11. Monolithic Parallel Tandem Organic Photovoltaic Cell with Transparent Carbon Nanotube Interlayer

    Science.gov (United States)

    Tanaka, S.; Mielczarek, K.; Ovalle-Robles, R.; Wang, B.; Hsu, D.; Zakhidov, A. A.

    2009-01-01

    We demonstrate an organic photovoltaic cell with a monolithic tandem structure in parallel connection. Transparent multiwalled carbon nanotube sheets are used as an interlayer anode electrode for this parallel tandem. The characteristics of front and back cells are measured independently. The short circuit current density of the parallel tandem cell is larger than the currents of each individual cell. The wavelength dependence of photocurrent for the parallel tandem cell shows the superposition spectrum of the two spectral sensitivities of the front and back cells. The monolithic three-electrode photovoltaic cell indeed operates as a parallel tandem with improved efficiency.

  12. Macroporous Titania Monolith Prepared via Sol-gel Process with Polymer Foam as the Template

    Institute of Scientific and Technical Information of China (English)

    REN, Jian; DU, Zhong-Jie; ZHANG, Chen; LI, Hang-Quan

    2006-01-01

    Macroporous titania monoliths were prepared via sol-gel method using polymer foam as templates. The polymer foam polymerized via concentrated emulsion polymerization was immerged in a solution of titanium(Ⅳ) isopropoxide in 2-propanol, which underwent a sol-gel process. The organic components were subsequently removed by calcination. The effects of various parameters, including the nature of the monomer, the volume fraction of dispersed phase of the concentrated emulsion, and concentration of the sol-gel solution were investigated. The SEM micrographs of the macroporous titania monoliths thus obtained showed that the porous structure of the final material was effectively controllable.

  13. Monolithic Parallel Tandem Organic Photovoltaic Cell with Transparent Carbon Nanotube Interlayer

    Science.gov (United States)

    Tanaka, S.; Mielczarek, K.; Ovalle-Robles, R.; Wang, B.; Hsu, D.; Zakhidov, A. A.

    2009-01-01

    We demonstrate an organic photovoltaic cell with a monolithic tandem structure in parallel connection. Transparent multiwalled carbon nanotube sheets are used as an interlayer anode electrode for this parallel tandem. The characteristics of front and back cells are measured independently. The short circuit current density of the parallel tandem cell is larger than the currents of each individual cell. The wavelength dependence of photocurrent for the parallel tandem cell shows the superposition spectrum of the two spectral sensitivities of the front and back cells. The monolithic three-electrode photovoltaic cell indeed operates as a parallel tandem with improved efficiency.

  14. Initial results for the silicon monolithically interconnected solar cell product

    Science.gov (United States)

    Dinetta, L. C.; Shreve, K. P.; Cotter, J. E.; Barnett, A. M.

    1995-01-01

    This proprietary technology is based on AstroPower's electrostatic bonding and innovative silicon solar cell processing techniques. Electrostatic bonding allows silicon wafers to be permanently attached to a thermally matched glass superstrate and then thinned to final thicknesses less than 25 micron. These devices are based on the features of a thin, light-trapping silicon solar cell: high voltage, high current, light weight (high specific power) and high radiation resistance. Monolithic interconnection allows the fabrication costs on a per watt basis to be roughly independent of the array size, power or voltage, therefore, the cost effectiveness to manufacture solar cell arrays with output powers ranging from milliwatts up to four watts and output voltages ranging from 5 to 500 volts will be similar. This compares favorably to conventionally manufactured, commercial solar cell arrays, where handling of small parts is very labor intensive and costly. In this way, a wide variety of product specifications can be met using the same fabrication techniques. Prototype solar cells have demonstrated efficiencies greater than 11%. An open-circuit voltage of 5.4 volts, fill factor of 65%, and short-circuit current density of 28 mA/sq cm at AM1.5 illumination are typical. Future efforts are being directed to optimization of the solar cell operating characteristics as well as production processing. The monolithic approach has a number of inherent advantages, including reduced cost per interconnect and increased reliability of array connections. These features make this proprietary technology an excellent candidate for a large number of consumer products.

  15. Monolithic semiconductor saturable absorber mirror with strain-compensated GaInAs/GaAsP quantum wells

    Science.gov (United States)

    Xiang, N.; Liu, H. F.; Kong, J.; Tang, D. Y.; Pessa, M.

    2007-04-01

    We report a monolithic broadband semiconductor saturable absorber mirror (SESAM) operating for 1025-1100 nm wavelength range with strain-compensated GaInAs/GaAsP quantum wells (QWs). By introducing tensile-strained GaAsP barriers, the compressive strain caused by the GaInAs QWs can be compensated and good quality QWs are obtained. Strain-compensated GaInAs/GaAsP QWs are grown on top of a GaAs/AlAs distributed Bragg reflector (DBR) to form the SESAM structure. The SESAM has a broad high-reflective stopband of about 120 nm and has been successfully used in passively modelocking a Nd:Gd 0.64Y 0.36VO 4 solid-state laser operating at 1064 nm wavelength. Optical pulses as short as 4.5 ps are generated with a peak power of 3.7 kW.

  16. High Power test of a low group velocity X-band Accelerator Structure for CLIC

    CERN Document Server

    Döbert, S; Riddone, G; Taborelli, M; Wuensch, W; Zennaro, R; Fukuda, S; Higashi, Y; Higo, T; Matsumoto, S; Ueno, K; Yokoyama, K; Adolphsen, C; Dolgashev, V; Laurent, L; Lewandowski, J; Tantawi, S; Wang, F; Wang, JW

    2008-01-01

    In recent years evidence has been found that the maximum sustainable gradient in an accelerating structure depends on the rf power flow through the structure. The CLIC study group has consequently designed a new prototype structure for CLIC with a very low group velocity, input power and average aperture ( = 0.13). The 18 cell structure has a group velocity of 2.6 % at the entrance and 1 % at the last cell. Several of these structures have been made in a collaboration between KEK, SLAC and CERN. A total of five brazed-disk structures and two quadrant structures have been made. The high power results of the first KEK/SLAC built structure is presented which reached an unloaded gradient in excess of 100 MV/m at a pulse length of 230 ns with a breakdown rate below 10-6 per meter active length. The high-power testing was done using the NLCTA facility at SLAC.

  17. In-situ estimation of structural power transmission from machinery source installations

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1999-01-01

    There is continued work on developing methods for characterising structureborne sound sources and for predicting the transmission of structural power into source foundations and receiving structures. However, at present there is no agreed measurement method by which such transmission predictions ...

  18. Monolithic View of Galaxy Formation and Evolution

    Directory of Open Access Journals (Sweden)

    Cesare Chiosi

    2014-07-01

    Full Text Available We review and critically discuss the current understanding of galaxy formation and evolution limited to Early Type Galaxies (ETGs as inferred from the observational data and briefly contrast the hierarchical and quasi-monolithic paradigms of formation and evolution. Since in Cold Dark Matter (CDM cosmogony small scale structures typically collapse early and form low-mass haloes that subsequently can merge to assembly larger haloes, galaxies formed in the gravitational potential well of a halo are also expected to merge thus assembling their mass hierarchically. Mergers should occur all over the Hubble time and large mass galaxies should be in place only recently. However, recent observations of high redshift galaxies tell a different story: massive ETGs are already in place at high redshift. To this aim, we propose here a revision of the quasi-monolithic scenario as an alternative to the hierarchical one, in which mass assembling should occur in early stages of a galaxy lifetime and present recent models of ETGs made of Dark and Baryonic Matter in a Λ-CDM Universe that obey the latter scheme. The galaxies are followed from the detachment from the linear regime and Hubble flow at z ≥ 20 down to the stage of nearly complete assembly of the stellar content (z ∼ 2 − 1 and beyond.  It is found that the total mass (Mh = MDM + MBM and/or initial over-density of the proto-galaxy drive the subsequent star formation histories (SFH. Massive galaxies (Mh ~ _1012M⊙ experience a single, intense burst of star formation (with rates ≥ 103M⊙/yr at early epochs, consistently with observations, with a weak dependence on the initial over-density; intermediate mass haloes (Mh~_ 1010 − 1011M⊙ have star formation histories that strongly depend on their initial over-density; finally, low mass haloes (Mh ~_ 109M⊙ always have erratic, burst-like star forming histories. The present-day properties (morphology, structure, chemistry and photometry of the

  19. Development of Control Structure for Hybrid Wind Generators with Active Power Capability

    Directory of Open Access Journals (Sweden)

    Mehdi Niroomand

    2014-01-01

    Full Text Available A hierarchical control structure is proposed for hybrid energy systems (HES which consist of wind energy system (WES and energy storage system (ESS. The proposed multilevel control structure consists of four blocks: reference generation and mode select, power balancing, control algorithms, and switching control blocks. A high performance power management strategy is used for the system. Also, the proposed system is analyzed as an active power filter (APF with ability to control the voltage, to compensate the harmonics, and to deliver active power. The HES is designed with parallel DC coupled structure. Simulation results are shown for verification of the theoretical analysis.

  20. Structural Design and Protective Methods for the 100 kW Shoreline Wave Power Station

    Institute of Scientific and Technical Information of China (English)

    游亚戈; 郑永红; 马玉久; 余志; 蒋念东

    2003-01-01

    The structural design and protective methods for the 100 kW shoreline wave power station in China are described in detail. The proper structural type is designed for effective minimization of wave loads and bending stress. Various protective devices are adopted to protect the station in the extreme conditions against excessive power of airflow, excessive torsion of the shaft, over-pressure of the chamber, over-speed of rotation, power failure, and so on. It turns out that the structural design and protective methods for the 100 kW shoreline wave power station are successful.

  1. Monolithic Integration of GaN-based LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Ao, Jin-Ping, E-mail: jpao@ee.tokushima-u.ac.jp [Institute of Technology and Science, University of Tokushima 2-1 Minami-Josanjima, Tokushima 770-8506 (Japan)

    2011-02-01

    The technology of monolithically integrated GaN-based light-emitting diodes (LEDs) is reported. First, the technology details to realize monolithic integration are described, including the circuit design for high-voltage and alternating current (AC) operation and the technologies for device isolation. The performances of the fabricated monolithic LED arrays are then demonstrated. A monolithic series array with totally 40 LEDs exhibited expected operation function under AC bias. The operation voltage of the array is 72 V when 20 LEDs were connected in series. Some modified circuit designs for high-voltage operation and other monolithic LED arrays are finally reviewed.

  2. Synthesis of Mesoporous Titania-Silica Monolith Composites — A Comprehensive Study on their Photocatalytic Degradation of Acid Blue 113 Dye Under UV Light

    Science.gov (United States)

    Thejaswini, Thurlapathi Vl; Prabhakaran, Deivasigamani

    2016-10-01

    The present work deals with the synthesis of bi-continuous macro and mesoporous crack-free titania-silica monoliths, with well-defined structural dimensions and high surface area. The work also highlights their potential photocatalytic environmental applications. The highly ordered titania-silica monoliths are synthesized through direct surface template method using organic precursors of silica and titania in the presence of surface directing agents such as pluronic P123 and PEG, under acetic acid medium. The monoliths are synthesized with different Ti/Si ratios to obtain monolithic designs that exhibit better photocatalytic activity for dye degradation. The titania-silica monoliths are characterized using XRD, SEM, EDAX, FT-IR, TG-DTA and BET analysis. The photocatalytic activity of the synthesized monoliths is tested on the photodegradation of a textile dye (acid blue 113). It is observed that the monolith with 7:3 ratio of Ti/Si showed significant photocatalysis behavior in the presence of UV light. The influence of various physico-chemical properties such as, solution pH, photocatalyst dosage, light intensity, dye concentration, effect of oxidants, etc. are analyzed and optimized using a customized photoreactor set-up. Under optimized conditions, the monoliths exhibited superior degradation kinetics, with the dye dissipation complete within 10min of photolysis. The mesoporous catalysts are recoverable and reusable up to four cycles of repeated usage.

  3. Monolithic resonant optical reflector laser diodes

    Science.gov (United States)

    Hirata, T.; Suehiro, M.; Maeda, M.; Hihara, M.; Hosomatsu, H.

    1991-10-01

    The first monolithic resonant optical reflector laser diode that has a waveguide directional coupler and two DBR reflectors integrated by compositional disordering of quantum-well heterostructures is described. A linewidth of 440 kHz was obtained, and this value is expected to be greatly decreased by reducing the propagation loss in the integrated waveguide.

  4. Constant capacitance in nanopores of carbon monoliths.

    Science.gov (United States)

    García-Gómez, Alejandra; Moreno-Fernández, Gelines; Lobato, Belén; Centeno, Teresa A

    2015-06-28

    The results obtained for binder-free electrodes made of carbon monoliths with narrow micropore size distributions confirm that the specific capacitance in the electrolyte (C2H5)4NBF4/acetonitrile does not depend significantly on the micropore size and support the foregoing constant result of 0.094 ± 0.011 F m(-2).

  5. Monolithic Active Pixel Matrix with Binary Counters (MAMBO) ASIC

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Farah F.; Deptuch, Grzegorz; Shenai, Alpana; Yarema, Raymond J.; /Fermilab

    2010-11-01

    Monolithic Active Matrix with Binary Counters (MAMBO) is a counting ASIC designed for detecting and measuring low energy X-rays from 6-12 keV. Each pixel contains analogue functionality implemented with a charge preamplifier, CR-RC{sup 2} shaper and a baseline restorer. It also contains a window comparator which can be trimmed by 4 bit DACs to remove systematic offsets. The hits are registered by a 12 bit ripple counter which is reconfigured as a shift register to serially output the data from the entire ASIC. Each pixel can be tested individually. Two diverse approaches have been used to prevent coupling between the detector and electronics in MAMBO III and MAMBO IV. MAMBO III is a 3D ASIC, the bottom ASIC consists of diodes which are connected to the top ASIC using {mu}-bump bonds. The detector is decoupled from the electronics by physically separating them on two tiers and using several metal layers as a shield. MAMBO IV is a monolithic structure which uses a nested well approach to isolate the detector from the electronics. The ASICs are being fabricated using the SOI 0.2 {micro}m OKI process, MAMBO III is 3D bonded at T-Micro and MAMBO IV nested well structure was developed in collaboration between OKI and Fermilab.

  6. Sparse gallium arsenide to silicon metal waferbonding for heterogeneous monolithic microwave integrated circuits

    Science.gov (United States)

    Bickford, Justin Robert

    Waferbonding is a technique that integrates different semiconductors together, in order to obtain hybrid structures that exploit the strengths of each material. Work was done at the University of California at San Diego to investigate the waferbonding of III/V compound semiconductors to silicon using a metal interface. GaAs and other III/V compound semiconductors surpass silicon in their ability to create high performance microwave devices, while silicon offers an inexpensive platform with a proven digital architecture that can interface with microwave devices and support passive components and driver circuitry. Intimate integration of the two will be required, as mixed RF/digital and optical/digital systems for communications devices such as cell phones, wi-fi, and optical communications systems are pushed smaller, faster, and to higher power. The metalbonding implementation of a proposed heterogeneous monolithic microwave integrated circuit (HMMIC) system was investigated, and was shown to extend the capabilities of existing homogeneous monolithic microwave integrated circuit (MMIC) systems. The main goals of this work were two-fold; first to implement a robust heterogeneous integration technique, and second, to show that this approach uniquely improves upon existing microwave integration technology. The metalbonding technique investigated sparsely integrated GaAs structures onto silicon, in pursuit of this HMMIC scheme. Both bottom-up and top-down fabrication methods were implemented. These approaches required the development of a myriad of meticulously designed fabrication procedures capable of avoiding the many incompatibilities between the compound semiconductor, bondmetal, and silicon materials. The bondmetal interface, provided by these techniques, broadens the scope of existing monolithic microwave integrated circuit technology design possibilities. Essential bond interface properties were measured to establish the performance of this heterogeneous

  7. Next High Performance and Low Power Flash Memory Package Structure

    Institute of Scientific and Technical Information of China (English)

    Jung-Hoon Lee

    2007-01-01

    In general, SAND flash memory has advantages in low power consumption, storage capacity, and fast erase/write performance in contrast to NOR flash. But, main drawback of the SAND flash memory is the slow access time for random read operations. Therefore, we proposed the new SAND flash memory package for overcoming this major drawback. We present a high performance and low power SAND flash memory system with a dual cache memory. The proposed SAND flash package consists of two parts, i.e., an SAND flash memory module, and a dual cache module. The new SAND flash memory system can achieve dramatically higher performance and lower power consumption compared with any conventional NAND-type flash memory module. Our results show that the proposed system can reduce about 78% of write operations into the flash memory cell and about 70% of read operations from the flash memory cell by using only additional 3KB cache space. This value represents high potential to achieve low power consumption and high performance gain.

  8. Facile preparation of organic-silica hybrid monolith for capillary hydrophilic liquid chromatography based on "thiol-ene" click chemistry.

    Science.gov (United States)

    Chen, Ming-Luan; Zhang, Jun; Zhang, Zheng; Yuan, Bi-Feng; Yu, Qiong-Wei; Feng, Yu-Qi

    2013-04-05

    In this work, a one-step approach to facile preparation of organic-inorganic hybrid monoliths was successfully developed. After vinyl-end organic monomers and azobisisobutyronitrile (AIBN) were mixed with hydrolyzed tetramethoxysilane (TMOS) and 3-mercaptopropyltrimethoxysilane (MPTMS), the homogeneous mixture was introduced into a fused-silica capillary for simultaneous polycondensation and "thiol-ene" click reaction to form the organic-silica hybrid monoliths. By employing this strategy, two types of organic-silica hybrid monoliths with positively charged quaternary ammonium and amide groups were prepared, respectively. The functional groups were successfully introduced onto the monoliths during the sol-gel process with "thiol-ene" click reaction, which was demonstrated by ζ-potential assessment, energy dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FT-IR) spectroscopy. The porous structure of the prepared monolithic columns was examined by scanning electron microscopy (SEM), nitrogen adsorption-desorption measurement, and mercury intrusion porosimetry. These results indicate the prepared organic-silica hybrid monoliths possess homogeneous column bed, large specific surface area, good mechanical stability, and excellent permeability. The prepared monolithic columns were then applied for anion-exchange/hydrophilic interaction liquid chromatography. Different types of analytes, including benzoic acids, inorganic ions, nucleosides, and nucleotides, were well separated with high column efficiency around 80,000-130,000 plates/m. Taken together, we present a facile and universal strategy to prepare organic-silica hybrid monoliths with a variety of organic monomers using one-step approach. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Synthesis of Mesoporous Silica Monoliths — A Novel Approach Towards Fabrication of Solid-State Optical Sensors for Environmental Applications

    Science.gov (United States)

    Prabhakaran, D.; Subashini, C.; Akhila Maheswari, M.

    2016-10-01

    Mesoporous silica monoliths are an attractive area of research owing to their high specific surface area, uniform channels and mesoporous size (2-30nm). This paper deals with the direct templating synthesis of a mesoporous worm-like silica monolithic material using F127 — a triblock copolymer, by micro-emulsion technique using trimethyl benzene (TMB), as the solvent. The synthesized silica monolith is characterized using SEM-EDAX, XRD, BET, NMR and FT-IR. The monolith shows an ordered worm-like mesoporous structure with tuneable through pores, an excellent host for the anchoring of chromo-ionophores for the naked-eye metal ion-sensing. The mesoporous monoliths were loaded with 4-dodecyl-6-(2-pyridylazo)-phenol (DPAP) ligand through direct immobilization, thereby acting as solid-state naked-eye colorimetric ion-sensors for the sensing toxic Pb(II) ions at parts-per-billion (ppb) level in various industrial and environmental systems. The influence of various experimental parameters such as solution pH, limiting ligand loading concentration, amount of monolith material, matrix tolerance level, limit of detection and quantification has been studied and optimized.

  10. The issue of statistical power for overall model fit in evaluating structural equation models

    Directory of Open Access Journals (Sweden)

    Richard HERMIDA

    2015-06-01

    Full Text Available Statistical power is an important concept for psychological research. However, examining the power of a structural equation model (SEM is rare in practice. This article provides an accessible review of the concept of statistical power for the Root Mean Square Error of Approximation (RMSEA index of overall model fit in structural equation modeling. By way of example, we examine the current state of power in the literature by reviewing studies in top Industrial-Organizational (I/O Psychology journals using SEMs. Results indicate that in many studies, power is very low, which implies acceptance of invalid models. Additionally, we examined methodological situations which may have an influence on statistical power of SEMs. Results showed that power varies significantly as a function of model type and whether or not the model is the main model for the study. Finally, results indicated that power is significantly related to model fit statistics used in evaluating SEMs. The results from this quantitative review imply that researchers should be more vigilant with respect to power in structural equation modeling. We therefore conclude by offering methodological best practices to increase confidence in the interpretation of structural equation modeling results with respect to statistical power issues.

  11. Bias Errors in Measurement of Vibratory Power and Implication for Active Control of Structural Vibration

    DEFF Research Database (Denmark)

    Ohlrich, Mogens; Henriksen, Eigil; Laugesen, Søren

    1997-01-01

    of a degree for the phase. This implies that input power at a single point can be measured to within one dB in practical structures which possesses some damping. The uncertainty is increased, however, when sums of measured power contributions from more sources are to be minimised, as is the case in active...... control of vibratory power transmission into structures. This is demonstrated by computer simulations using a theoretical model of a beam structure which is driven by one primary source and two control sources. These simulations reveal the influence of residual errors on power measurements......, and the limitations imposed in active control of structural vibration based upon a strategy of power minimisation....

  12. EML Array fabricated by SAG technique monolithically integrated with a buried ridge AWG multiplexer

    Science.gov (United States)

    Xu, Junjie; Liang, Song; Zhang, Zhike; An, Junming; Zhu, Hongliang; Wang, Wei

    2017-06-01

    We report the fabrication of a ten channel electroabsorption modulated DFB laser (EML) array. Different emission wavelengths of the laser array are obtained by selective area growth (SAG) technique, which is also used for the integration of electroabsorption modulators (EAM) with the lasers. An arrayed waveguide grating (AWG) combiner is integrated monolithically with the laser array by butt-joint regrowth (BJR) technique. A buried ridge waveguide structure is adopted for the AWG combiner. A self aligned fabrication procedure is adopted for the fabrication of the waveguide structure of the device to eliminate the misalignment between the laser active waveguide and the passive waveguide. A Ti thin film heater is integrated for each laser in the array. With the help of the heaters, ten laser emissions with 1.8 nm channel spacing are obtained. The integrated EAM has a larger than 11 dB static extinction ratios and larger than 8 GHz small signal modulation bandwidths. The light power collected in the output waveguide of the AWG is larger than -13 dBm for each wavelength.

  13. Power Law Behavior of Structural Properties of Protein Gels

    NARCIS (Netherlands)

    Verheul, Marleen; Roefs, Sebastianus P.F.M.; Mellema, Jorrit; Kruif, Kees G.

    1998-01-01

    Whey proteins are globular, heat-sensitive proteins. The gel structure, the formation of this structure, and the rheological properties of particulate whey protein isolate (WPI) gels have been investigated. On increasing the NaCl concentration, the permeability of the WPI gels increased, indicating

  14. Design analysis of phosphor-free monolithic white light-emitting-diodes with InGaN/ InGaN multiple quantum wells on ternary InGaN substrates

    Directory of Open Access Journals (Sweden)

    Yu Kee Ooi

    2015-05-01

    Full Text Available Phosphor-free monolithic white light emitting diodes (LEDs based on InGaN/ InGaN multiple quantum wells (MQWs on ternary InGaN substrates are proposed and analyzed in this study. Simulation studies show that LED devices composed of multi-color-emitting InGaN/ InGaN quantum wells (QWs employing ternary InGaN substrate with engineered active region exhibit stable white color illumination with large output power (∼ 170 mW and high external quantum efficiency (EQE (∼ 50%. The chromaticity coordinate for the investigated monolithic white LED devices are located at (0.30, 0.28 with correlated color temperature (CCT of ∼ 8200 K at J = 50 A/cm2. A reference LED device without any nanostructure engineering exhibits green color emission shows that proper engineered structure is essential to achieve white color illumination. This proof-of-concept study demonstrates that high-efficiency and cost-effective phosphor-free monolithic white LED is feasible by the use of InGaN/ InGaN MQWs on ternary InGaN substrate combined with nanostructure engineering, which would be of great impact for solid state lighting.

  15. Design analysis of phosphor-free monolithic white light-emitting-diodes with InGaN/ InGaN multiple quantum wells on ternary InGaN substrates

    Energy Technology Data Exchange (ETDEWEB)

    Ooi, Yu Kee, E-mail: Yu.Kee.Ooi@rit.edu; Zhang, Jing, E-mail: Jing.Zhang@rit.edu [Department of Electrical and Microelectronics Engineering, Rochester Institute of Technology, Rochester, New York 14623 (United States)

    2015-05-15

    Phosphor-free monolithic white light emitting diodes (LEDs) based on InGaN/ InGaN multiple quantum wells (MQWs) on ternary InGaN substrates are proposed and analyzed in this study. Simulation studies show that LED devices composed of multi-color-emitting InGaN/ InGaN quantum wells (QWs) employing ternary InGaN substrate with engineered active region exhibit stable white color illumination with large output power (∼ 170 mW) and high external quantum efficiency (EQE) (∼ 50%). The chromaticity coordinate for the investigated monolithic white LED devices are located at (0.30, 0.28) with correlated color temperature (CCT) of ∼ 8200 K at J = 50 A/cm{sup 2}. A reference LED device without any nanostructure engineering exhibits green color emission shows that proper engineered structure is essential to achieve white color illumination. This proof-of-concept study demonstrates that high-efficiency and cost-effective phosphor-free monolithic white LED is feasible by the use of InGaN/ InGaN MQWs on ternary InGaN substrate combined with nanostructure engineering, which would be of great impact for solid state lighting.

  16. Design analysis of phosphor-free monolithic white light-emitting-diodes with InGaN/ InGaN multiple quantum wells on ternary InGaN substrates

    Science.gov (United States)

    Ooi, Yu Kee; Zhang, Jing

    2015-05-01

    Phosphor-free monolithic white light emitting diodes (LEDs) based on InGaN/ InGaN multiple quantum wells (MQWs) on ternary InGaN substrates are proposed and analyzed in this study. Simulation studies show that LED devices composed of multi-color-emitting InGaN/ InGaN quantum wells (QWs) employing ternary InGaN substrate with engineered active region exhibit stable white color illumination with large output power (˜ 170 mW) and high external quantum efficiency (EQE) (˜ 50%). The chromaticity coordinate for the investigated monolithic white LED devices are located at (0.30, 0.28) with correlated color temperature (CCT) of ˜ 8200 K at J = 50 A/cm2. A reference LED device without any nanostructure engineering exhibits green color emission shows that proper engineered structure is essential to achieve white color illumination. This proof-of-concept study demonstrates that high-efficiency and cost-effective phosphor-free monolithic white LED is feasible by the use of InGaN/ InGaN MQWs on ternary InGaN substrate combined with nanostructure engineering, which would be of great impact for solid state lighting.

  17. Individual, Interpersonal, and Structural Power: Associations With Condom Use in a Sample of Young Adult Latinos.

    Science.gov (United States)

    Stokes, Lynissa R; Harvey, S Marie; Warren, Jocelyn T

    2016-01-01

    Interviews were conducted with 480 sexually active Latino young adults from four rural counties in Oregon. We examined relationships between three levels of power (individual, interpersonal, and structural) and consistent condom use. Condom use self-efficacy and sexual decision-making, examples of individual and interpersonal measures of power, respectively, were associated with increased odds of consistent condom use among both men and women. Among men only, increasing relationship control, an interpersonal measure of power, was associated with lower odds of consistent condom use. Among women only, increasing medical mistrust, a structural measure of power, was associated with increased odds of consistent condom use.

  18. Life management of power plant based on structural damage testing

    Energy Technology Data Exchange (ETDEWEB)

    Tallermo, H.; Klevtsov, I. [Thermal Engineering Department of Tallinn Technical University, Tallinn (Estonia); Arras, V. [Eesti Energia, Tallinn (Estonia)

    1998-12-31

    Life management system is based on the valid nowadays in Estonian power plants regulation documentation. The system allows to estimate stress distribution in components, find computational assessment of cumulated creep damage, determine when and where it is necessary to cut off the particular number of microsamples or take replicas. Finally, the real metal condition may be assessed on the basis of metallographic specimen research and reasonable 3-R decision - run, repair, replacement - made on further component use. (orig.) 6 refs.

  19. Polyurea-Based Aerogel Monoliths and Composites

    Science.gov (United States)

    Lee, Je Kyun

    2012-01-01

    aerogel insulation material was developed that will provide superior thermal insulation and inherent radiation protection for government and commercial applications. The rubbery polyureabased aerogel exhibits little dustiness, good flexibility and toughness, and durability typical of the parent polyurea polymer, yet with the low density and superior insulation properties associated with aerogels. The thermal conductivity values of polyurea-based aerogels at lower temperature under vacuum pressures are very low and better than that of silica aerogels. Flexible, rubbery polyurea-based aerogels are able to overcome the weak and brittle nature of conventional inorganic and organic aerogels, including polyisocyanurate aerogels, which are generally prepared with the one similar component to polyurethane rubber aerogels. Additionally, with higher content of hydrogen in their structures, the polyurea rubber-based aerogels will also provide inherently better radiation protection than those of inorganic and carbon aerogels. The aerogel materials also demonstrate good hydrophobicity due to their hydrocarbon molecular structure. There are several strategies to overcoming the drawbacks associated with the weakness and brittleness of silica aerogels. Development of the flexible fiber-reinforced silica aerogel composite blanket has proven to be one promising approach, providing a conveniently fielded form factor that is relatively robust in industrial environments compared to silica aerogel monoliths. However, the flexible, silica aerogel composites still have a brittle, dusty character that may be undesirable, or even intolerable, in certain application environments. Although the cross - linked organic aerogels, such as resorcinol- formaldehyde (RF), polyisocyanurate, and cellulose aerogels, show very high impact strength, they are also very brittle with little elongation (i.e., less rubbery). Also, silica and carbon aerogels are less efficient radiation shielding materials due

  20. Constitutive Theory Developed for Monolithic Ceramic Materials

    Science.gov (United States)

    Janosik, Lesley A.

    1998-01-01

    with these service conditions by developing a multiaxial viscoplastic constitutive model that accounts for time-dependent hereditary material deformation (such as creep and stress relaxation) in monolithic structural ceramics. Using continuum principles of engineering mechanics, we derived the complete viscoplastic theory from a scalar dissipative potential function.

  1. Effect of the presence of an ordered micro-pillar array on the formation of silica monoliths.

    Science.gov (United States)

    Detobel, Frederik; Eghbali, Hamed; De Bruyne, Selm; Terryn, Herman; Gardeniers, Han; Desmet, Gert

    2009-10-30

    We report on the synthesis of siloxane-based monoliths in the presence of a two-dimensional, perfectly ordered array of micro-pillars. Both methyltrimethoxysilane- and tetramethoxysilane-based monoliths were considered. The obtained structures were analyzed using scanning-electron microscopy and can be explained from the general theory of surface-directed phase separation in confined spaces. The formed structures are to a large extent nearly exclusively determined by the ratio between the bulk domain size of the monolith on the one hand and the distance between the micro-pillars on the other hand. When this ratio is small, the presence of the pillars has nearly no effect on the morphology of the produced monoliths. However, when the ratio approaches unity and ascends above it, some new types of monolith morphologies are induced, two of which appear to have interesting properties for use as novel chromatographic supports. One of these structures (obtained when the domain size/inter-pillar distance ratio is around unity) is a 3D network of linear interconnections between the pillars, organized such that all skeleton branches are oriented perpendicular to the micro-pillar surface. A second interesting structure is obtained at even higher values of the domain size/inter-pillar distance ratio. In this case, each individual micro-pillar is uniformly coated with a mesoporous shell.

  2. Macroporous monoliths for trace metal extraction from seawater

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Yanfeng; Mayes, Richard; Gill, Gary A.; Kuo, Li-Jung; Wood, Jordana R.; Binder, Andrew; Brown, Suree; Dai, Sheng

    2015-05-29

    The viability of seawater-based uranium recovery depends on the uranium adsorption rate and capacity, since the concentration of uranium in the oceans is relatively low (3.3 μgL⁻¹). An important consideration for a fast adsorption is to maximize the adsorption properties of adsorbents such as surface areas and pore structures, which can greatly improve the kinetics of uranium extraction and the adsorption capacity simultaneously. Following this consideration, macroporous monolith adsorbents were prepared from the copolymerization of acrylonitrile (AN) and N,N’-methylenebis(acrylamide) (MBAAm) based on a cryogel method using both hydrophobic and hydrophilic monomers. The monolithic sorbents were tested with simulated seawater containing a high uranyl concentration (–6 ppm) and the uranium adsorption results showed that the adsorption capacities are strongly influenced by the ratio of monomer to the crosslinker, i.e., the density of the amidoxime groups. The preliminary seawater testing indicates the high salinity content of seawater does not hinder the adsorption of uranium.

  3. Monolithic blue LED series arrays for high-voltage AC operation

    Energy Technology Data Exchange (ETDEWEB)

    Ao, Jin-Ping [Satellite Venture Business Laboratory, University of Tokushima, Tokushima 770-8506 (Japan); Sato, Hisao; Mizobuchi, Takashi; Morioka, Kenji; Kawano, Shunsuke; Muramoto, Yoshihiko; Sato, Daisuke; Sakai, Shiro [Nitride Semiconductor Co. Ltd., Naruto, Tokushima 771-0360 (Japan); Lee, Young-Bae; Ohno, Yasuo [Department of Electrical and Electronic Engineering, University of Tokushima, Tokushima 770-8506 (Japan)

    2002-12-16

    Design and fabrication of monolithic blue LED series arrays that can be operated under high ac voltage are described. Several LEDs, such as 3, 7, and 20, are connected in series and in parallel to meet ac operation. The chip size of a single device is 150 {mu}m x 120 {mu}m and the total size is 1.1 mm x 1 mm for a 40(20+20) LED array. Deep dry etching was performed as device isolation. Two-layer interconnection and air bridge are utilized to connect the devices in an array. The monolithic series array exhibit the expected operation function under dc and ac bias. The output power and forward voltage are almost proportional to LED numbers connected in series. On-wafer measurement shows that the output power is 40 mW for 40(20+20) LED array under ac 72 V. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  4. Multifunctional Structure for Exploration Rovers Integrating Power and Storage Capabilities

    Science.gov (United States)

    Atxaga, G.; Arrizabalaga, I.; Alonso, R.; Segura, M.; Mendizabal, M.; Marcos, J.; Cook, A.; Walker, S.; Foster, J.; Kireitseu, M.; Fontana, Q.

    2014-06-01

    A need for light-weight structures with a performance comparable to current solutions and which satisfies future scientific needs is identified to be important for future planetary surface exploration missions. Improvements are necessary on the reduction of the mass of the systems that constitute the Rover. Multifunctional structures are envisioned as possible breakthroughs in the recent advances to reduce space systems mass and volume.One of the activities of ROV-E project has dealt with the development of an external panel integrating solar cells in the external skin and using a battery as core of the structure. The integration of the battery in the structure provides mass and volume savings and therefore an increase the overall efficiency of the system.This paper summarizes the main findings obtained in this activity.

  5. Fabrication of Tunable Sampled Grating DBR Laser Integrated Monolithically with Optical Semiconductor Amplifier Using Planar Buried Heterostructure

    Science.gov (United States)

    Oh, Su Hwan; Lee, Ji-Myon; Kim, Soo; Ko, Hyunsung; Lee, Chul-Wook; Park, Sahnggi; Park, Moon-Ho

    2004-10-01

    We have demonstrated a high-power widely tunable sampled grating (SG) DBR laser integrated monolithically with optical semiconductor amplifier (SOA), using planar buried heterostructure (PBH). The measured threshold current was 5 mA on average with 60 chips randomly selected which is lowest among the typical average values. Fiber-coupled output power was 12.4 dBm and the output power variation was ˜1 dB for the whole tuning range.

  6. Monolithic watt-level millimeter-wave diode-grid frequency tripler array

    Science.gov (United States)

    Hwu, R. J.; Luhmann, N. C., Jr.; Rutledge, D. B.; Hancock, B.; Lieneweg, U.

    1988-01-01

    In order to provide watt-level CW output power throughout the millimeter and submillimeter wave region, thousands of solid-state diodes have been monolithically integrated using a metal grid to produce a highly efficient frequency multiplier. Devices considered include GaAs Schottky diodes, thin MOS diodes, and GaAs Barrier-Intrinsic-N(+)diodes. The performance of the present compact low-cost device has been theoretically and experimentally validated.

  7. Power systems and electromagnetic safety in of powerful utility buildings and structures

    Directory of Open Access Journals (Sweden)

    О.І. Запорожець

    2008-01-01

    Full Text Available  Researching of origin terms of electromagnetic contaminations from the unbalanced currents and leak currents in the industrial networks of electric supply of structures and buildings saturated energy.

  8. The power of data: structural bioinformatics yesterday and today

    KAUST Repository

    Tramontano, Anna

    2016-01-25

    The protein structure database was established in 1971. At the time it contained seven structures, today there are more than 100,000. The improvement is not only a matter of quantity, but also of quality. Did we effectively exploit this information to gain knowledge? The answer is certainly affirmative. I will illustrate how this wealth of experimental data has allowed us to explore the landscape of macromolecular structures on one side, and to uncover the properties of specific protein families on the other. The latter plays an essential role in pursuing exciting new avenues in biomedical and biotechnological sciences. Experimental data are also part of a virtuous cycle whereby they reinforce and guide our ability to infer unknown macromolecular structures, which, while providing relevant information to scientists, permits to gauge the level of our understanding of the complex problem of protein folding. A paradigmatic example of the latter is represented by the “Critical Assessment of Techniques for Protein Structure Prediction” (CASP) initiative that I will briefly discuss.

  9. Design of an Improved Type Rotary Inductive Coupling Structure for Rotatable Contactless Power Transfer System

    Directory of Open Access Journals (Sweden)

    Lee Jia-You

    2015-01-01

    Full Text Available This paper is aimed at analyzing the rotary inductive coupling structure of contactless rotary transformer. The main feature of the proposed rotatable contactless power transfer system is which winding is coaxial-interlayered for improving the magnetic coupling capability. There is no ferrite core used in the secondary-side of the rotary inductive coupling structure, this helps to ease the exerted force that is stress by the secondary-side on spindle. In order to verify the feasibility of the proposed contactless power transfer system for rotary applications, an inductive powered rotary machinery and the control system have been integrated. The experimental results show that the maximum power transfer efficiency of the proposed rotary inductive coupling structure is about 94.8%. The maximum output power received in the load end is 1030 W with transmission efficiency of 88%.

  10. Power

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2016-01-01

    In this chapter, we will explore the dynamics of power in processes of creativity, and show its paradoxical nature as both a bridge and a barrier to creativity in organisations. Recent social psychological experimental research (Slighte, de Dreu & Nijstad, 2011) on the relation between power...... and creativity suggests that when managers give people the opportunity to gain power and explicate that there is reason to be more creative, people will show a boost in creative behaviour. Moreover, this process works best in unstable power hierarchies, which implies that power is treated as a negotiable...... and floating source for empowering people in the organisation. We will explore and discuss here the potentials, challenges and pitfalls of power in relation to creativity in the life of organisations today. The aim is to demonstrate that power struggles may be utilised as constructive sources of creativity...

  11. Technological and Physical Compatibilities in Hybrid Integration of Laser and Monolithic Integration of Waveguide, Photodetector and CMOS Circuits on Silicon

    NARCIS (Netherlands)

    Zhou, M.J.; Ikkink, T.; Chalmers, J.; Kranenburg, H. van; Albers, H.; Holleman, J.; Lambeck, P.V.; Joppe, J.L.; Bekman, H.H.P.T.; Krijger, A.J.T. de

    1994-01-01

    In this paper, technological and physical compatibilities in hybrid integration of AlInGaP laser and monolithic integration of ZnO monomode waveguide, pin-photodetector, CMOS circuits for laser power control and signal amplification on silicon substrate are studied. Prospective problems and their po

  12. Technological and physical compatibilities in hybrid integration of laser and monolithic integration of waveguide, photodetector and CMOS circuits on silicon

    NARCIS (Netherlands)

    Zhou, Ming-Jiang; Ikkink, Ton; Chalmers, John; Kranenburg, van Herma; Albers, Hans; Holleman, Jisk; Lambeck, Paul; Joppe, Jan Leendert; Bekman, Herman; Krijger, de Ton; Lambeck, P.V.

    1994-01-01

    In this paper, technological and physical compatibilities in hybrid integration of AlInGaP laser and monolithic integration of ZnO monomode waveguide, pin-photodetector, CMOS circuits for laser power control and signal amplification on silicon substrate are studied. Prospective problems and their po

  13. Macroporous Monolithic Polymers: Preparation and Applications

    Directory of Open Access Journals (Sweden)

    Cecilia Inés Alvarez Igarzabal

    2009-12-01

    Full Text Available In the last years, macroporous monolithic materials have been introduced as a new and useful generation of polymers used in different fields. These polymers may be prepared in a simple way from a homogenous mixture into a mold and contain large interconnected pores or channels allowing for high flow rates at moderate pressures. Due to their porous characteristics, they could be used in different processes, such as stationary phases for different types of chromatography, high-throughput bioreactors and in microfluidic chip applications. This review reports the contributions of several groups working in the preparation of different macroporous monoliths and their modification by immobilization of specific ligands on the products for specific purposes.

  14. Monolithic 1310nm buried heterostructure VCSEL using InGaAsP/InP DBR reflectors

    Science.gov (United States)

    Francis, Daniel A.; Young, David B.; Walker, Jeff; Verma, Ashish; Gold, Dave; Decker, Chris

    2005-10-01

    We report on the first monolithic 1310 nm Vertical Cavity Surface Emitting Lasers (VCSELs) with top and bottom InGaAsP/InP distributed Bragg reflectors (DBRs). The lasers show single mode powers over 1.0 mW at room temperature and single mode powers up to 0.5 mW at 85 °C. The lasers, designed to be single mode, have side mode suppression ratios exceeding 45 dB over all temperatures and all powers.

  15. Update On Monolithic Fuel Fabrication Development

    Energy Technology Data Exchange (ETDEWEB)

    C. R Clark; J. M. Wight; G. C. Knighton; G. A. Moore; J. F. Jue

    2005-11-01

    Efforts to develop a viable monolithic research reactor fuel plate have continued at Idaho National Laboratory. These efforts have concentrated on both fabrication process refinement and scale-up to produce full sized fuel plates. Advancements have been made in the production of U-Mo foil including full sized foils. Progress has also been made in the friction stir welding and transient liquid phase bonding fabrication processes resulting in better bonding, more stable processes and the ability to fabricate larger fuel plates.

  16. Monolithically integrated interferometer for optical displacement measurement

    Science.gov (United States)

    Hofstetter, Daniel; Zappe, Hans P.

    1996-01-01

    We discuss the fabrication of a monolithically integrated optical displacement sensors using III-V semiconductor technology. The device is configured as a Michelson interferometer and consists of a distributed Bragg reflector laser, a photodetector and waveguides forming a directional coupler. Using this interferometer, displacements in the 100 nm range could be measured at distances of up to 45 cm. We present fabrication, device results and characterization of the completed interferometer, problems, limitations and future applications will also be discussed.

  17. Optimization of Electric Power Leveling Systems by a Novel Cluster-Structured GA with Masking

    Science.gov (United States)

    Itoh, Jyunpei; Fujii, Toshinori; Funabiki, Shigeyuki

    Power fluctuations of the rolling mill may cause the instability of electric power systems, and increase the cost of the electric power facility and electricity charges. Therefore, in order to compensate the power fluctuations, the development of the electric power-leveling systems (EPLS) is very important in the future electric power system. The EPLS with a SMES has been proposed as one of the countermeasures for the electric power quality improvement. However, the SMES is very expensive and it is difficult to decide the gains of the controller. It is essential in the practical use that the reduction of SMES capacity is realized. This paper proposes a new optimization method of the EPLS. The proposed algorithm is Cluster-Structured GA with Masking (CSGA). The optimization of the EPLS can be achieved by the proposed CSGA compared to the GA.

  18. Using Structural Equation Modeling to Assess Functional Connectivity in the Brain: Power and Sample Size Considerations

    Science.gov (United States)

    Sideridis, Georgios; Simos, Panagiotis; Papanicolaou, Andrew; Fletcher, Jack

    2014-01-01

    The present study assessed the impact of sample size on the power and fit of structural equation modeling applied to functional brain connectivity hypotheses. The data consisted of time-constrained minimum norm estimates of regional brain activity during performance of a reading task obtained with magnetoencephalography. Power analysis was first…

  19. Theorizing power in transition studies: the role of creativity and novel practices in structural change

    NARCIS (Netherlands)

    J. Hoffman

    2013-01-01

    An important theoretical challenge for theorizing about power dynamics in societal transitions is the transformation of power itself. In this respect, it is especially puzzling how agency at the level of novel practices can extend beyond the habitual, how it can draw on structures and destructure at

  20. Monolithic translucent BaMgAl10O17:Eu2+ phosphors for laser-driven solid state lighting

    Directory of Open Access Journals (Sweden)

    Clayton Cozzan

    2016-10-01

    Full Text Available With high power light emitting diodes and laser diodes being explored for white light generation and visible light communication, thermally robust encapsulation schemes for color-converting inorganic phosphors are essential. In the current work, the canonical blue-emitting phosphor, high purity Eu-doped BaMgAl10O17, has been prepared using microwave-assisted heating (25 min and densified into translucent ceramic phosphor monoliths using spark plasma sintering (30 min. The resulting translucent ceramic monoliths convert UV laser light to blue light with the same efficiency as the starting powder and provide superior thermal management in comparison with silicone encapsulation.

  1. Monolithic translucent BaMgAl10O17:Eu2+ phosphors for laser-driven solid state lighting

    Science.gov (United States)

    Cozzan, Clayton; Brady, Michael J.; O'Dea, Nicholas; Levin, Emily E.; Nakamura, Shuji; DenBaars, Steven P.; Seshadri, Ram

    2016-10-01

    With high power light emitting diodes and laser diodes being explored for white light generation and visible light communication, thermally robust encapsulation schemes for color-converting inorganic phosphors are essential. In the current work, the canonical blue-emitting phosphor, high purity Eu-doped BaMgAl10O17, has been prepared using microwave-assisted heating (25 min) and densified into translucent ceramic phosphor monoliths using spark plasma sintering (30 min). The resulting translucent ceramic monoliths convert UV laser light to blue light with the same efficiency as the starting powder and provide superior thermal management in comparison with silicone encapsulation.

  2. Humour: Power conveying social structures inside forensic mental health nursing

    DEFF Research Database (Denmark)

    Gildberg, Frederik Alkier; Paaske, Kristian Jul; Rasmussen, Vivian L.;

    2016-01-01

    mental health staff members in interactions with forensic mental health inpatients. The study included 32 forensic mental health staffmembers, used 307 hours of participant observations, 48 informal interviews, and seven formal semistructured nterviews. Outcomes identify four themes concerning...... the conveyance of power to, from, and between forensic mental health staff and patients as they interact: (a) “the informal use: the human-to-human approach,” characterized by an informal use of humor and without any reference tomental health issues; (b) the “formal use of humor: the staff–patient approach......,” characterized as formalwith a view on the patient as mentally ill, unable to understand humor, and with the aim of using humor to prevent conflicts or negative behavior; (c) “protest against requested care: the human–patient approach,” characterized by the use of humor as a protest against requested care...

  3. An overview of monolithic zirconia in dentistry

    Directory of Open Access Journals (Sweden)

    Özlem Malkondu

    2016-07-01

    Full Text Available Zirconia restorations have been used successfully for years in dentistry owing to their biocompatibility and good mechanical properties. Because of their lack of translucency, zirconia cores are generally veneered with porcelain, which makes restorations weaker due to failure of the adhesion between the two materials. In recent years, all-ceramic zirconia restorations have been introduced in the dental sector with the intent to solve this problem. Besides the elimination of chipping, the reduced occlusal space requirement seems to be a clear advantage of monolithic zirconia restorations. However, scientific evidence is needed to recommend this relatively new application for clinical use. This mini-review discusses the current scientific literature on monolithic zirconia restorations. The results of in vitro studies suggested that monolithic zirconia may be the best choice for posterior fixed partial dentures in the presence of high occlusal loads and minimal occlusal restoration space. The results should be supported with much more in vitro and particularly in vivo studies to obtain a final conclusion.

  4. Comparing the Topological and Electrical Structure of the North American Electric Power Infrastructure

    Science.gov (United States)

    Cotilla-Sanchez, Eduardo; Hines, Paul D. H.; Barrows, Clayton; Blumsack, Seth

    2012-12-01

    The topological (graph) structure of complex networks often provides valuable information about the performance and vulnerability of the network. However, there are multiple ways to represent a given network as a graph. Electric power transmission and distribution networks have a topological structure that is straightforward to represent and analyze as a graph. However, simple graph models neglect the comprehensive connections between components that result from Ohm's and Kirchhoff's laws. This paper describes the structure of the three North American electric power interconnections, from the perspective of both topological and electrical connectivity. We compare the simple topology of these networks with that of random (Erdos and Renyi, 1959), preferential-attachment (Barabasi and Albert, 1999) and small-world (Watts and Strogatz, 1998) networks of equivalent sizes and find that power grids differ substantially from these abstract models in degree distribution, clustering, diameter and assortativity, and thus conclude that these topological forms may be misleading as models of power systems. To study the electrical connectivity of power systems, we propose a new method for representing electrical structure using electrical distances rather than geographic connections. Comparisons of these two representations of the North American power networks reveal notable differences between the electrical and topological structure of electric power networks.

  5. [Organizational structure of nursing services: reflections on the influence of the organizational power and culture].

    Science.gov (United States)

    Jericó, Marli Carvalho; Peres, Aida Maris; Kurcgant, Paulina

    2008-09-01

    This study addresses the culture and power influencing the organizational structure of the nursing services at a teaching hospital. The Nursing Service organizational structure (organization chart) was outlined due to the need of the general management of the hospital to standardize the nursing procedures. Due to this situation, the nursing managers' interest has arisen to widen the power setting, strengthening nursing in an intra-institutional environment.

  6. Preparation of imprinted monolithic column under molecular crowding conditions

    Institute of Scientific and Technical Information of China (English)

    Xiao Xia Li; Xin Liu; Li Hong Bai; Hong Quan Duan; Yan Ping Huang; Zhao Sheng Liu

    2011-01-01

    Molecular crowding is a new concept to obtain molecularly imprinted polymers (MIPs) with greater capacity and selectivity. In this work, molecular crowding agent was firstly applied to the preparation of MIPs monolithic column. A new polymerization system based on molecular crowding surrounding was developed to prepare enrofloxacin-imprinted monolith, which was composed of polystyrene and tetrahydrofuran. The result showed that the monolithic MIPs under molecular crowding conditions presented good molecular recognition for enrofloxacin with an imprinting factor of 3.03.

  7. Powerful chemical technique. [CSIR uses new x-ray diffractometer for structural chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    The CSIR's National Chemical Research Laboratory (NCRL) is now using one of the most powerful techniques available to determine the structure of molecules. It has recently acquired a Single Crystal X-ray Diffractometer. This powerful method provides the only means of determining the structure of certain compounds. NCRL scientists often carry out structure determinations to find out the relative or absolute stereochemistry of molecules. This is important when correlating physiological activity and structure, information which is necessary for synthesizing medicines with specific characteristics.

  8. Influence of China’s Grain Industrial Market Structure over Grain Pricing Power

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    From the point of view of industrial market structure,we analyze the influence of market structure on grain production,circulation,and processing,and on the grain pricing power of entities along China’s grain industrial chain.Through analysis,it is indicated that different features of market structure play a significant role in pricing power of such microeconomic entities as farmers and grain enterprises in grain production and transaction.And the market structure determines welfare distribution model of consumers’ surplus and producers’ surplus at the market.

  9. Dynamic stiffness for thin-walled structures by power series

    Institute of Scientific and Technical Information of China (English)

    ZHU Bin; LEUNG A.Y.T.

    2006-01-01

    The dynamic stiffness method is introduced to analyze thin-walled structures including thin-walled straight beams and spatial twisted helix beam. A dynamic stiffness matrix is formed by using frequency dependent shape functions which are exact solutions of the governing differential equations. With the obtained thin-walled beam dynamic stiffness matrices, the thin-walled frame dynamic stiffness matrix can also be formulated by satisfying the required displacements compatibility and forces equilibrium, a method which is similar to the finite element method (FEM). Then the thin-walled structure natural frequencies can be found by equating the determinant of the system dynamic stiffness matrix to zero. By this way, just one element and several elements can exactly predict many modes of a thin-walled beam and a spatial thin-walled frame, respectively. Several cases are studied and the results are compared with the existing solutions of other methods. The natural frequencies and buckling loads of these thin-walled structures are computed.

  10. Development of a monolithic polymer pipette for solid-phase extraction of liquiritigenin in rat plasma

    Institute of Scientific and Technical Information of China (English)

    Hong Wu Zhang; Kang Li; Zhi Xian Liang; Feng Yang Wang; Qi Wen Lu

    2012-01-01

    A monolithic polymer column with mixed-mode interaction was prepared by in situ polymerization in a 1000 μ,L pipette.Two kinds of monomers,butyl methacrylate (BMA) and 2-(dimethylamino)ethyl methacrylate (DMAM) were applied to constructing the mixed-mode interaction of monolithic polymer column.Its solid-phase extraction properties for liquiritigenin (LQG) were evaluated by high performance liquid chromatography (HPLC) with a gradient elution procedure.After the extraction procedure was optimized,the maximum binding capacity and extraction recovery following the optimal extraction procedure were investigated.Calibration curve was expressed as A =65.9C + 4.53 (r2 =0.998) with a linear range of 0.151-1.80 μg/mL.The experimental results indicate that the monolithic polymer pipette presents good extraction efficiency for LQG.It can be envisaged that the developed monolithic polymer pipette possesses the potential for its application to the enrichment of other flavonoids compounds being siniilar to the structure of LQG.

  11. Effect on mass transference phenomena by textural change inside monolithic carbon aerogels

    Science.gov (United States)

    Chejne, F.; Camargo-Trillos, D.; Pabón, E.; Carrasco-Marin, F.

    2015-08-01

    The effects on mass transference phenomena due textural changes of monolithic carbon aerogels were studied by hexane adsorption. The monolithic carbon aerogels were prepared after carbonization of the organic aerogels obtained by resorcinol-formaldehyde polymerization, using p-toluenesulfonic acid (acid-catalyst) and sodium carbonate catalysts (basic-catalyst). Internal texture was modified by CO2 activation. The characterization by gas adsorption showed that the monolithic carbon aerogels presents a bi-modal pore size distribution with presence of both microporous and mesoporous. It was shown that the activation process of monolithic carbon aerogels increases their micropore volume bigger than the other one acid-catalyst aerogel. The mesopores volume in the carbon aerogels plays an important role on mass transport mechanism. The samples with presence of significant mesopore volume present a lower height of mass transfer zone than others less mesopore volume; therefore better efficiency of adsorption in mass transfer zone in dynamic adsorption. The breakthrough curve methodology proposed in this work has allowed finding a relationship between the structural parameters and dynamic adsorption variables, which opens new approaches for measuring textural parameters of material.

  12. Preparation of a thermoresponsive polymer grafted polystyrene monolithic capillary for the separation of bioactive compounds.

    Science.gov (United States)

    Koriyama, Takuya; Asoh, Taka-Aki; Kikuchi, Akihiko

    2016-11-01

    To develop aqueous microseparation columns for bioactive compounds, a thermoresponsive polymer grafted polymer monolith was prepared inside silica capillaries having an I.D. of 100μm by polymerization of styrene (St) with m/p-divinylbenzene (DVB) in the presence of polydimethylsiloxane as porogen, followed by surface-initiated atom transfer radical polymerization (SI-ATRP) of N-isopropylacrylamide (NIPAAm). SEM analysis indicated that the resulting poly(N-isopropylacrylamide) (PNIPAAm) grafted polystyrene monolith had a consecutive three-dimensionally interconnected structure and through-pores, similar to the base polystyrene (PSt) monolith. The elution behavior of steroids with different hydrophobicity was evaluated using micro-high-performance liquid chromatography in sole aqueous mobile phase. Temperature dependent interaction changes were observed between steroids and the PNIPAAm modified surfaces. Furthermore, the interaction between bioactive compounds and the PNIPAAm grafted PSt surfaces was controlled and eventually separate these molecules with different hydrophobicities by simple temperature modulation in aqueous environment. The PNIPAAm grafted PSt monolithic capillary showed improved separation properties of bioactive compounds, compared with a PNIPAAm grafted hollow capillary in aqueous environment.

  13. Preparation and evaluation of a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid.

    Science.gov (United States)

    Shan, Yuanhong; Qiao, Lizhen; Shi, Xianzhe; Xu, Guowang

    2015-01-02

    To develop a novel hybrid monolithic column based on pentafluorobenzyl imidazolium bromide ionic liquid, a new ionic liquid monomer was synthesized from 1-vinylimidazole and pentafluorobenzyl bromide. By employing a facile one-step copolymerization of polyhedral-oligomeric-silsesquioxane-type (POSS) cross-linking agent and the home-made ionic liquid monomer, the hybrid monolithic columns were in situ fabricated in fused-silica capillary. The morphology of monolithic column was characterized by scanning electron microscope (SEM) and the chemical composition was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and elemental analysis. Excellent mechanical stability and slight swelling propensity were exhibited which was ascribed to the rigid hybrid monolithic skeleton. Reproducibility results of run-to-run, column-to-column, batch-to-batch and day-to-day were investigated and the RSDs were less than 0.46%, 1.84%, 3.96% and 3.17%, respectively. The mixed-mode retention mechanism with hydrophobic interaction, π-π stacking, ion-exchange, electrostatic interaction and dipole-dipole interaction was explored systematically using analytes with different structure types. Satisfied separation capability and column efficiency were achieved for the analysis of small molecular compounds such as alkylbenzenes, polycyclic aromatic hydrocarbons, nucleosides and halogenated compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Improvement in Liquid Chromatographic Performance of Organic Polymer Monolithic Capillary Columns with Controlled Free-Radical Polymerization.

    Science.gov (United States)

    Gama, Mariana R; Aggarwal, Pankaj; Liu, Kun; Lee, Milton L; Bottoli, Carla B G

    2016-12-19

    Capillary columns containing butyl or lauryl methacrylate monoliths were prepared using two different free-radical polymerization methods: conventional free-radical polymerization and controlled/living free-radical polymerization, both initiated thermally, and these methods were compared for the first time. Both monolith morphology and chromatographic efficiency were compared for the synthesized stationary phases using scanning electronic microscopy (SEM) and capillary liquid chromatography, respectively. Columns prepared using controlled method gave better chromatographic performance for both monomers tested. The lauryl-based monolith showed 7-fold improvement in chromatographic efficiency with a plate count of 42,000 plates/m (corrected for dead volume) for a non-retained compound. Columns fabricated using controlled polymerization appeared more homogenous radially with fused small globular morphologies, evaluated by SEM, and lower column permeability. The columns were compared with respect to resolving power of a series of alkylbenzenes under isocratic and gradient elution conditions.

  15. Design Study of an 8 Meter Monolithic Mirror UV/Optical Space Telescope

    Science.gov (United States)

    Stahl, H. Philip

    2008-01-01

    This paper will review a recent NASA MSFC preliminary study that demonstrated the feasibility of launching a 6 to 8 meter class monolithic primary mirror telescope to Sun-Earth L2 using an Ares V. The study started with the unique capabilities of the Ares V vehicle and examined the feasibility of launching a large aperture low cost low risk telescope based on a conventional ground based glass primary mirror. Specific technical areas studied included optical design; structural design/analysis including primary mirror support structure, sun shade and secondary mirror support structure; thermal analysis; launch vehicle performance and trajectory; spacecraft including structure, propulsion, GN & C, avionics, power systems and reaction wheels; operations & servicing, mass budget and system cost. The study telescope was an on-axis three-mirror anastigmatic design with a fine steering mirror. The observatory has a 100 arc-minute (8.4 X 12 arc-minutes) of diffraction limited field of view at a wavelength les than 500 nm. The study assumed that the primary mirror would be fabricated from an existing Schott Zerodur residual VLT blank edged to 6.2 meters, 175 mm thick at the edge with a mass of 11,000 kg. The entire mass budget for the observatory including primary mirror, structure, light baffle tube, instruments, space craft, avionics, etc. is less than 40,000 kg - a 33% mass margin on the Ares V's 60,000 kg Sun-Earth L2 capability. An 8 meter class observatory would have a total mass of less than 60,000 kg of which the primary mirror is the largest contributor.

  16. Monolithically integrated mid-infrared sensor using narrow mode operation and temperature feedback

    Science.gov (United States)

    Ristanic, Daniela; Schwarz, Benedikt; Reininger, Peter; Detz, Hermann; Zederbauer, Tobias; Andrews, Aaron Maxwell; Schrenk, Werner; Strasser, Gottfried

    2015-01-01

    A method to improve the sensitivity and selectivity of a monolithically integrated mid-infrared sensor using a distributed feedback laser (DFB) is presented in this paper. The sensor is based on a quantum cascade laser/detector system built from the same epitaxial structure and with the same fabrication approach. The devices are connected via a dielectric-loaded surface plasmon polariton waveguide with a twofold function: it provides high light coupling efficiency and a strong interaction of the light with the environment (e.g., a surrounding fluid). The weakly coupled DFB quantum cascade laser emits narrow mode light with a FWHM of 2 cm-1 at 1586 cm-1. The room temperature laser threshold current density is 3 kA/cm2 and a pulsed output power of around 200 mW was measured. With the superior laser noise performance, due to narrow mode emission and the compensation of thermal fluctuations, the lower limit of detection was expanded by one order of magnitude to the 10 ppm range.

  17. Monolithically integrated mid-infrared sensor using narrow mode operation and temperature feedback

    Energy Technology Data Exchange (ETDEWEB)

    Ristanic, Daniela; Schwarz, Benedikt, E-mail: benedikt.schwarz@tuwien.ac.at; Reininger, Peter; Detz, Hermann; Zederbauer, Tobias; Andrews, Aaron Maxwell; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics and Center for Micro- and Nanostructures, Vienna University of Technology, Floragasse 7, Vienna 1040 (Austria)

    2015-01-26

    A method to improve the sensitivity and selectivity of a monolithically integrated mid-infrared sensor using a distributed feedback laser (DFB) is presented in this paper. The sensor is based on a quantum cascade laser/detector system built from the same epitaxial structure and with the same fabrication approach. The devices are connected via a dielectric-loaded surface plasmon polariton waveguide with a twofold function: it provides high light coupling efficiency and a strong interaction of the light with the environment (e.g., a surrounding fluid). The weakly coupled DFB quantum cascade laser emits narrow mode light with a FWHM of 2 cm{sup −1} at 1586 cm{sup −1}. The room temperature laser threshold current density is 3 kA∕cm{sup 2} and a pulsed output power of around 200 mW was measured. With the superior laser noise performance, due to narrow mode emission and the compensation of thermal fluctuations, the lower limit of detection was expanded by one order of magnitude to the 10 ppm range.

  18. Robotic Powered Transfer Mechanism modeling on Human Muscle Structure

    Science.gov (United States)

    Saito, Yukio

    It is considered in engineering that one power source can operate one joint. However, support movement mechanism of living organism is multi joint movement mechanism. Considerably different from mechanical movement mechanism, two pairs of uni-articular muscles and a pair of bi-articular muscles are involved in it. In leg, movements observed in short run including leg idling, heel contact and toeing are operated by bi-articular muscles of the thigh showing strong legs to support body weight. Pursuit of versatility in welfare robot brings its comparison with conventional machinery or industrial robot to the fore. Request for safety and technology allowing elderly people to operate the robot is getting stronger in the society. The robot must be safe when it is used together with other welfare equipment and simpler system avoiding difficult operation has to be constructed. Appearance of recent care and assistance robot is getting similar to human arm in comparison with industrial robot. Being easily able to imagine from industrial robot, mid-heavyweight articulated robot to support 60-70kgf combined with large output motor and reduction gears is next to impossible to be installed in the bath room. This research indicated that upper limb arm and lower limb thigh of human and animals are holding coalitional muscles and movement of uni-artcular muscle and bi-articular muscle conjure the image of new actuators.

  19. Humor: Power Conveying Social Structures Inside Forensic Mental Health Nursing.

    Science.gov (United States)

    Gildberg, Frederik A; Paaske, Kristian J; Rasmussen, Vivian L; Nissen, Ricko D; Bradley, Stephen K; Hounsgaard, Lise

    2016-01-01

    According to research literature, humor inside the staff-patient interaction seems to be significant in the area of forensic mental healthcare. However, existing literature on the subject is limited. Therefore, the aim of this study was to explore the characteristics of the use humor by forensic mental health staff members in interactions with forensic mental health inpatients. The study included 32 forensic mental health staff members, used 307 hours of participant observations, 48 informal interviews, and seven formal semistructured interviews. Outcomes identify four themes concerning the conveyance of power to, from, and between forensic mental health staff and patients as they interact: (a) "the informal use: the human-to-human approach," characterized by an informal use of humor and without any reference to mental health issues; (b) the "formal use of humor: the staff-patient approach," characterized as formal with a view on the patient as mentally ill, unable to understand humor, and with the aim of using humor to prevent conflicts or negative behavior; (c) "protest against requested care: the human-patient approach," characterized by the use of humor as a protest against requested care; and the use of (d) "inadequacy humor: the staff-human approach," characterized by the use of inadequacy-humor referring to, for example, patients' physical features. Recommendations and clinical implications are discussed.

  20. Statistical Power Analysis with Missing Data A Structural Equation Modeling Approach

    CERN Document Server

    Davey, Adam

    2009-01-01

    Statistical power analysis has revolutionized the ways in which we conduct and evaluate research.  Similar developments in the statistical analysis of incomplete (missing) data are gaining more widespread applications. This volume brings statistical power and incomplete data together under a common framework, in a way that is readily accessible to those with only an introductory familiarity with structural equation modeling.  It answers many practical questions such as: How missing data affects the statistical power in a study How much power is likely with different amounts and types

  1. New Structure of Governor Electrohydraulic Power which meets the Requirements of the Implemented LFC-System

    Directory of Open Access Journals (Sweden)

    Mariusz Pawlak

    2014-03-01

    Full Text Available The construction and operation of a control system of a power unit turboset has been described. The controllers use the CWP (Current Work Point signal from the ACFP (Automatic Control Frequency and Power system. Such an installation has been made on a power unit in a Power Plant. The control system functions, principle of operation, structure, software and investigation results have been presented. The new LFC (Load Frequency Control system has been described in this paper. The benefits for the energy-producer are mentioned. Increasing complexity of the control systems of steam turbines has called for the development of diagnostic methods and measures.

  2. Enhanced phase-locked loop structures for power and energy applications

    CERN Document Server

    Karimi-Ghartema, Masoud

    2014-01-01

    Many excellent books covering phase-locked loops (PLLs) have been published; however, there is practically no book that covers the specifics of PLLs as employed in power systems. The usefulness for such a book fills an immediate need. Existing books cover the type of PLLs used in electronics, communications and instrumentation. Over the past decade or so, many new PLL structures have been developed to address the new requirements in modern power systems. The enhanced phase-locked loop (EPLL) is arguably the most widely accepted structure developed to address power system requirements. It is no

  3. Effect of side transmission of power ultrasonic on structure of AZ81 magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    张海波; 翟启杰; 戚飞鹏; 龚永勇

    2004-01-01

    In order to promote the application of power ultrasonic in metallurgic industry, ultrasonic vibration is introduced from the side of AZ81 ingot by adopting the automatic-attracting amplitude transformer horn which has independently been designed and produced, and the effect of the side transmission of ultrasonic on the solidification structure of metal is investigated. The results show that under this experimental condition, power ultrasonic can greatly improve the solidification structure of AZ81 magnesium alloy. Compared with the traditional modification methods in which inoculants are added into melt, power ultrasonic has a better performance. The present research gives us a new way for the application of ultrasonic refinement technique.

  4. Yttria-stabilized zirconia solid oxide electrolyte fuel cells: Monolithic solid oxide fuel cells

    Science.gov (United States)

    1990-10-01

    The monolithic solid oxide fuel cell (MSOFC) is currently under development for a variety of applications including coal-based power generation. The MSOFC is a design concept that places the thin components of a solid oxide fuel cell in lightweight, compact, corrugated structure, and so achieves high efficiency and excellent performance simultaneously with high power density. The MSOFC can be integrated with coal gasification plants and is expected to have high overall efficiency in the conversion of the chemical energy of coal to electrical energy. This report describes work aimed at: (1) assessing manufacturing costs for the MSOFC and system costs for a coal-based plant; (2) modifying electrodes and electrode/electrolyte interfaces to improve the electrochemical performance of the MSOFC; and (3) testing the performance of the MSOFC on hydrogen and simulated coal gas. Manufacturing costs for both the coflow and crossflow MSOFC's were assessed based on the fabrication flow charts developed by direct scaleup of tape calendering and other laboratory processes. Integrated coal-based MSOFC systems were investigated to determine capital costs and costs of electricity. Design criteria were established for a coal-fueled 200-Mw power plant. Four plant arrangements were evaluated, and plant performance was analyzed. Interfacial modification involved modification of electrodes and electrode/electrolyte interfaces to improve the MSOFC electrochemical performance. Work in the cathode and cathode/electrolyte interface was concentrated on modification of electrode porosity, electrode morphology, electrode material, and interfacial bonding. Modifications of the anode and anode/electrolyte interface included the use of additives and improvement of nickel distribution. Single cells have been tested for their electrochemical performance. Performance data were typically obtained with humidified H2 or simulated coal gas and air or oxygen.

  5. Increased power to weight ratio of piezoelectric energy harvesters through integration of cellular honeycomb structures

    Science.gov (United States)

    Chandrasekharan, N.; Thompson, L. L.

    2016-04-01

    The limitations posed by batteries have compelled the need to investigate energy harvesting methods to power small electronic devices that require very low operational power. Vibration based energy harvesting methods with piezoelectric transduction in particular has been shown to possess potential towards energy harvesters replacing batteries. Current piezoelectric energy harvesters exhibit considerably lower power to weight ratio or specific power when compared to batteries the harvesters seek to replace. To attain the goal of battery-less self-sustainable device operation the power to weight ratio gap between piezoelectric energy harvesters and batteries need to be bridged. In this paper the potential of integrating lightweight honeycomb structures with existing piezoelectric device configurations (bimorph) towards achieving higher specific power is investigated. It is shown in this study that at low excitation frequency ranges, replacing the solid continuous substrate of conventional bimorph with honeycomb structures of the same material results in a significant increase in power to weight ratio of the piezoelectric harvester. At higher driving frequency ranges it is shown that unlike the traditional piezoelectric bimorph with solid continuous substrate, the honeycomb substrate bimorph can preserve optimum global design parameters through manipulation of honeycomb unit cell parameters. Increased operating lifetime and design flexibility of the honeycomb core piezoelectric bimorph is demonstrated as unit cell parameters of the honeycomb structures can be manipulated to alter mass and stiffness properties of the substrate, resulting in unit cell parameter significantly influencing power generation.

  6. Evaluation of the clenbuterol imprinted monolithic column prepared by reversible addition-fragmentation chain transfer polymerization

    Institute of Scientific and Technical Information of China (English)

    Mamat Turson; Xiao Lei Zhuang; Hui Na Liu; Ping Jiang; Xiang Chao Dong

    2009-01-01

    To make more homogenous organic monolithic structure,reversible addition-fragmentation chain transfer(RAFT)process was employed in the synthesis of the clenbuterol imprinted polymer.In the synthesis,the influence of synthetic conditions on the polymer structure and separation efficiency was studied.The result demonstrated that the imprinted columns prepared with RAFT process have higher column efficiency and selectivity than the columns prepared with conventional polymerization in the present study,which may result from the higher surface area,smaller pore size and the narrower globule size distribution in their structures.The result indicated that RAFT polymerization provided better conditions for the clenbuterol imprinted monolithic polymer preparation.

  7. Design And Structural Analysis Of A Powered Wheelchair Transmission

    Science.gov (United States)

    Geonea, Ionut Daniel; Dumitru, Nicolae; Margine, Alexandru

    2015-09-01

    In this paper are presented the author's researches on designing, dynamical and structural evaluation of a transmission for a wheelchair, intended to persons with locomotors disabilities. The kinematics of proposed transmission is analyzed in order to realize a proper synthesis and design of gears. A 3D model of the transmission and wheelchair are designed in Solid Works, and they will be used for the dynamic simulation of the wheelchair robotic system in Adams software. In Adams is analyzed wheelchair trajectory and dynamics for a combined trajectory: linear motion and steering. Dynamic parameters obtained from simulation are used to perform a finite element analysis of bevel and worm gears. Simulation results reveal the transmission dynamics parameters, emphasize the efficiency of the transmission and enable implementation of this design to a wheelchair model.

  8. Monolithic silica aerogel - material design on the nano-scale

    DEFF Research Database (Denmark)

    Jensen, Karsten Ingerslev; Schultz, Jørgen Munthe; Kristiansen, Finn Harken

    By means of a production process in two major steps - a sol/gel process and a supercritical drying – open-cell, monolithic silica aerogel can be made. This material can have a density in the range of 30- to 300 kg/m3, corresponding to porosities between 86 and 98 %. The solid structure has...... of piezoelectric transducers. - Other applications could be; waste encapsulation, spacers for vacuum insulation panels, membranes, etc. Department of Civil Engineering is co-ordinator of a current EU FP5 research project1, which deals with the application of aerogel as transparent insulation materials in windows....... Due to the excellent optical and thermal properties of aerogel, it is possible to develop windows with both high insulation and high transmittance, which is impossible applying the conventional window techniques, i.e. extra layers of glass, low-e coatings and gas fillings. It can be shown...

  9. Monolithic growth of partly cured polydimethylsiloxane thin film layers

    DEFF Research Database (Denmark)

    Yu, Liyun; Skov, Anne Ladegaard

    2014-01-01

    The demand for monolithic structures in many applications has increased to enable more reliable and optimized performances such as for dielectric electroactive polymers (DEAPs). For the layers of the elements to grow efficiently together, it is first of all required that the layers adhere together...... as thermal stabilities of the bilayer elastomer films are observed to change with the curing time of the monolayers before lamination. The objective of this work is to create adhesion of two layers without destroying the original viscoelastic properties of the PDMS films, and hence enable, for example......, adhesion of two microstructured films which is currently a crucial step in the large-scale production of DEAPs. © 2014 The Society of Polymer Science, Japan (SPSJ) All rights reserved....

  10. Monolith filter apparatus and membrane apparatus, and method using same

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, Robert L [Wayland, MA

    2012-04-03

    A filtration apparatus that separates a liquid feedstock mixed with a gas into filtrate and retentate, the apparatus including at least one filtration device comprised of at least one monolith segment of porous material that defines a plurality of passageways extending longitudinally from a feed face of the structure to a retentate end face. The filtration device contains at least one filtrate conduit within it for carrying filtrate toward a filtrate collection zone, the filtrate conduit providing a path of lower flow resistance than that of alternative flow paths through the porous material of the device. The filtration device can also be utilized as a membrane support for a device for microfiltration, ultrafiltration, nanofiltration, reverse osmosis, or pervaporation. Also disclosed is a method for using such a filtration apparatus.

  11. Towards monolithic integration of germanium light sources on silicon chips

    Science.gov (United States)

    Saito, Shinichi; Zaher Al-Attili, Abdelrahman; Oda, Katsuya; Ishikawa, Yasuhiko

    2016-04-01

    Germanium (Ge) is a group-IV indirect band gap semiconductor, and therefore bulk Ge cannot emit light efficiently. However, the direct band gap energy is close to the indirect one, and significant engineering efforts are being made to convert Ge into an efficient gain material monolithically integrated on a Si chip. In this article, we will review the engineering challenges of developing Ge light sources fabricated using nano-fabrication technologies compatible with complementary metal-oxide-semiconductor processes. In particular, we review recent progress in applying high-tensile strain to Ge to reduce the direct band gap. Another important technique is doping Ge with donor impurities to fill the indirect band gap valleys in the conduction band. Realization of carrier confinement structures and suitable optical cavities will be discussed. Finally, we will discuss possible applications of Ge light sources in potential photonics-electronics convergent systems.

  12. Monolithic microwave integrated circuits for sensors, radar, and communications systems; Proceedings of the Meeting, Orlando, FL, Apr. 2-4, 1991

    Science.gov (United States)

    Leonard, Regis F.; Bhasin, Kul B.

    Consideration is given to MMICs for airborne phased arrays, monolithic GaAs integrated circuit millimeter wave imaging sensors, accurate design of multiport low-noise MMICs up to 20 GHz, an ultralinear low-noise amplifier technology for space communications, variable-gain MMIC module for space applications, a high-efficiency dual-band power amplifier for radar applications, a high-density circuit approach for low-cost MMIC circuits, coplanar SIMMWIC circuits, recent advances in monolithic phased arrays, and system-level integrated circuit development for phased-array antenna applications. Consideration is also given to performance enhancement in future communications satellites with MMIC technology insertion, application of Ka-band MMIC technology for an Orbiter/ACTS communications experiment, a space-based millimeter wave debris tracking radar, low-noise high-yield octave-band feedback amplifiers to 20 GHz, quasi-optical MESFET VCOs, and a high-dynamic-range mixer using novel balun structure. (For individual items see A93-25777 to A93-25814)

  13. Miniature multimode monolithic flextensional transducers.

    Science.gov (United States)

    Hladky-Hennion, Anne-Christine; Uzgur, A Erman; Markley, Douglas C; Safari, Ahmad; Cochran, Joe K; Newnham, Robert E

    2007-10-01

    Traditional flextensional transducers classified in seven groups based on their designs have been used extensively in 1-100 kHz range for mine hunting, fish finding, oil explorations, and biomedical applications. In this study, a new family of small, low cost underwater, and biomedical transducers has been developed. After the fabrication of transducers, finite-elements analysis (FEA) was used extensively in order to optimize these miniature versions of high-power, low-frequency flextensional transducer designs to achieve broad bandwidth for both transmitting and receiving, engineered vibration modes, and optimized acoustic directivity patterns. Transducer topologies with various shapes, cross sections, and symmetries can be fabricated through high-volume, low-cost ceramic and metal extrusion processes. Miniaturized transducers posses resonance frequencies in the range of above 1 MHz to below 10 kHz. Symmetry and design of the transducer, polling patterns, driving and receiving electrode geometries, and driving conditions have a strong effect on the vibration modes, resonance frequencies, and radiation patterns. This paper is devoted to small, multimode flextensional transducers with active shells, which combine the advantages of small size and low-cost manufacturing with control of the shape of the acoustic radiation/receive pattern. The performance of the transducers is emphasized.

  14. On the impossibility of acquiring more powerful structures: A neglected alternative.

    NARCIS (Netherlands)

    Molenaar, P.C.M.

    1986-01-01

    Suggests that J. A. Fodor's (1975, 1980, 1981) extreme functionalism is unwarranted insofar as it leads to a categorical exclusion of the structural processes involved in cognitive development. An explicit consideration of these processes indicates the possibility of more powerful structures, emergi

  15. Multi-layered hierarchical nanostructures for transparent monolithic dye-sensitized solar cell architectures

    Science.gov (United States)

    Passoni, Luca; Fumagalli, Francesco; Perego, Andrea; Bellani, Sebastiano; Mazzolini, Piero; Di Fonzo, Fabio

    2017-06-01

    Monolithic dye-sensitized solar cell (DSC) architectures hold great potential for building-integrated photovoltaics applications. They indeed benefit from lower weight and manufacturing costs as they avoid the use of a transparent conductive oxide (TCO)-coated glass counter electrode. In this work, a transparent monolithic DSC comprising a hierarchical 1D nanostructure stack is fabricated by physical vapor deposition techniques. The proof of concept device comprises hyperbranched TiO2 nanostructures, sensitized by the prototypical N719, as photoanode, a hierarchical nanoporous Al2O3 spacer, and a microporous indium tin oxide (ITO) top electrode. An overall 3.12% power conversion efficiency with 60% transmittance outside the dye absorption spectral window is demonstrated. The introduction of a porous TCO layer allows an efficient trade-off between transparency and power conversion. The porous ITO exhibits submicrometer voids and supports annealing temperatures above 400 °C without compromising its optoelectronical properties. After thermal annealing at 500 °C, the resistivity, mobility, and carrier concentration of the 800 nm-thick porous ITO layer are found to be respectively 2.3 × 10-3 Ω cm-1, 11 cm2 V-1 s-1, and 1.62 × 1020 cm-3, resulting in a series resistance in the complete device architecture of 45 Ω. Electrochemical impedance and intensity-modulated photocurrent/photovoltage spectroscopy give insight into the electronic charge dynamic within the hierarchical monolithic DSCs, paving the way for potential device architecture improvements.

  16. Selective oxidation of cyclohexene through gold functionalized silica monolith microreactors

    Science.gov (United States)

    Alotaibi, Mohammed T.; Taylor, Martin J.; Liu, Dan; Beaumont, Simon K.; Kyriakou, Georgios

    2016-04-01

    Two simple, reproducible methods of preparing evenly distributed Au nanoparticle containing mesoporous silica monoliths are investigated. These Au nanoparticle containing monoliths are subsequently investigated as flow reactors for the selective oxidation of cyclohexene. In the first strategy, the silica monolith was directly impregnated with Au nanoparticles during the formation of the monolith. The second approach was to pre-functionalize the monolith with thiol groups tethered within the silica mesostructure. These can act as evenly distributed anchors for the Au nanoparticles to be incorporated by flowing a Au nanoparticle solution through the thiol functionalized monolith. Both methods led to successfully achieving even distribution of Au nanoparticles along the length of the monolith as demonstrated by ICP-OES. However, the impregnation method led to strong agglomeration of the Au nanoparticles during subsequent heating steps while the thiol anchoring procedure maintained the nanoparticles in the range of 6.8 ± 1.4 nm. Both Au nanoparticle containing monoliths as well as samples with no Au incorporated were tested for the selective oxidation of cyclohexene under constant flow at 30 °C. The Au free materials were found to be catalytically inactive with Au being the minimum necessary requirement for the reaction to proceed. The impregnated Au-containing monolith was found to be less active than the thiol functionalized Au-containing material, attributable to the low metal surface area of the Au nanoparticles. The reaction on the thiol functionalized Au-containing monolith was found to depend strongly on the type of oxidant used: tert-butyl hydroperoxide (TBHP) was more active than H2O2, likely due to the thiol induced hydrophobicity in the monolith.

  17. Smart Sensing Strip Using Monolithically Integrated Flexible Flow Sensor for Noninvasively Monitoring Respiratory Flow.

    Science.gov (United States)

    Jiang, Peng; Zhao, Shuai; Zhu, Rong

    2015-12-15

    This paper presents a smart sensing strip for noninvasively monitoring respiratory flow in real time. The monitoring system comprises a monolithically-integrated flexible hot-film flow sensor adhered on a molded flexible silicone case, where a miniaturized conditioning circuit with a Bluetooth4.0 LE module are packaged, and a personal mobile device that wirelessly acquires respiratory data transmitted from the flow sensor, executes extraction of vital signs, and performs medical diagnosis. The system serves as a wearable device to monitor comprehensive respiratory flow while avoiding use of uncomfortable nasal cannula. The respiratory sensor is a flexible flow sensor monolithically integrating four elements of a Wheatstone bridge on single chip, including a hot-film resistor, a temperature-compensating resistor, and two balancing resistors. The monitor takes merits of small size, light weight, easy operation, and low power consumption. Experiments were conducted to verify the feasibility and effectiveness of monitoring and diagnosing respiratory diseases using the proposed system.

  18. A Monolithic CMOS Magnetic Hall Sensor with High Sensitivity and Linearity Characteristics.

    Science.gov (United States)

    Huang, Haiyun; Wang, Dejun; Xu, Yue

    2015-10-27

    This paper presents a fully integrated linear Hall sensor by means of 0.8 μm high voltage complementary metal-oxide semiconductor (CMOS) technology. This monolithic Hall sensor chip features a highly sensitive horizontal switched Hall plate and an efficient signal conditioner using dynamic offset cancellation technique. An improved cross-like Hall plate achieves high magnetic sensitivity and low offset. A new spinning current modulator stabilizes the quiescent output voltage and improves the reliability of the signal conditioner. The tested results show that at the 5 V supply voltage, the maximum Hall output voltage of the monolithic Hall sensor microsystem, is up to ±2.1 V and the linearity of Hall output voltage is higher than 99% in the magnetic flux density range from ±5 mT to ±175 mT. The output equivalent residual offset is 0.48 mT and the static power consumption is 20 mW.

  19. Development of a Monolithic Research Reactor Fuel Type at Argonne National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C.R.; Briggs, R.J.

    2004-10-06

    The Reduced Enrichment for Research and Test Reactors (RERTR) program has been tasked with the conversion of research reactors from highly enriched to low-enriched uranium (LEU). To convert several high power reactors, monolithic fuel, a new fuel type, is being developed. This fuel type replaces the standard fuel dispersion with a fuel alloy foil, which allows for fuel densities far in excess of that found in dispersion fuel. The single-piece fuel foil also contains a significantly lower interface area between the fuel and the aluminum in the plate than the standard fuel type, limiting the amount of detrimental fuel-aluminum interaction that can occur. Implementation of monolithic fuel is dependant on the development of a suitable fabrication method as traditional roll-bonding techniques are inadequate.

  20. In-situ estimation of structural power transmission from machinery source installations

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1999-01-01

    There is continued work on developing methods for characterising structureborne sound sources and for predicting the transmission of structural power into source foundations and receiving structures. However, at present there is no agreed measurement method by which such transmission predictions...... are assessed and validated. This fundamental problem is addressed herein and a reference method is proposed for measuring power transmission ‘in-situ'. The method is founded on a relatively simple structural power calibration of the source environment (receiving structure), which is done before the source...... is installed. Moreover, it is shown that an approximate transmission estimate can be obtained with the source presence, provided that either the source or receiver mobility is known a priori for a single mounting terminal. This is tested for a number of complex source-receiver arrangements and the frequency...

  1. Optimal wireless receiver structure for omnidirectional inductive power transmission to biomedical implants.

    Science.gov (United States)

    Gougheri, Hesam Sadeghi; Kiani, Mehdi

    2016-08-01

    In order to achieve omnidirectional inductive power transmission to biomedical implants, the use of several orthogonal coils in the receiver side (Rx) has been proposed in the past. In this paper, the optimal Rx structure for connecting three orthogonal Rx coils and the power management is found to achieve the maximum power delivered to the load (PDL) in the presence of any Rx coil tilting. Unlike previous works, in which a separate power management has been used for each coil to deliver power to the load, different resonant Rx structures for connecting three Rx coils to a single power management are studied. In simulations, connecting three Rx coils with the diameters of 3 mm, 3.3 mm, and 3.6 mm in series and resonating them with a single capacitor at the operation frequency of 100 MHz led to the maximum PDL for large loads when the implant was tilted for 45o. This optimal Rx structure achieves higher PDL in worst-case scenarios as well as reduces the number of power managements to only one.

  2. Developing a Computerized Aging Management System for Concrete Structures in Finnish Nuclear Power Plants

    Directory of Open Access Journals (Sweden)

    Hradil P.

    2013-07-01

    Full Text Available Finland has four nuclear reactors units in two power plants. The first unit started operation in 1977 and in the early 1980's all four units were in use. During the last few years the aging management of the Nuclear Power Plant's (NPP concrete structures has grown an important issue because the existing structures are reaching the end of their licensed operating lifetime (about 40 years. Therefore the nuclear power companies are developing aging management systems to avoid premature degradation of NPP facilities and to be able to extend their operating lifetime. This paper is about the development of a computerized ageing management system for the nuclear power plants concrete structures. The computerized ageing management system is built upon central database and implementation applications. It will assist the personnel of power companies to implement the aging management activities at different phases of the lifetime of a power plant. It will provide systematic methods for planning, surveillance, inspection, monitoring, condition assessment, maintenance and repair of structures.

  3. Developing a Computerized Aging Management System for Concrete Structures in Finnish Nuclear Power Plants

    Science.gov (United States)

    Al-Neshawy, F.; Piironen, J.; Sistonen, E.; Vesikari, E.; Tuomisto, M.; Hradil, P.; Ferreira, M.

    2013-07-01

    Finland has four nuclear reactors units in two power plants. The first unit started operation in 1977 and in the early 1980's all four units were in use. During the last few years the aging management of the Nuclear Power Plant's (NPP) concrete structures has grown an important issue because the existing structures are reaching the end of their licensed operating lifetime (about 40 years). Therefore the nuclear power companies are developing aging management systems to avoid premature degradation of NPP facilities and to be able to extend their operating lifetime. This paper is about the development of a computerized ageing management system for the nuclear power plants concrete structures. The computerized ageing management system is built upon central database and implementation applications. It will assist the personnel of power companies to implement the aging management activities at different phases of the lifetime of a power plant. It will provide systematic methods for planning, surveillance, inspection, monitoring, condition assessment, maintenance and repair of structures.

  4. 3D photon impact determination in monolithic crystals based on autocorrelation filters and RTP methods

    Energy Technology Data Exchange (ETDEWEB)

    Conde, Pablo; Gonzalez, Antonio [Institute for Instrumentation in Molecular Imaging, I3M-CSIC, Valencia (Spain); Bettiol, Marco; Fabbri, Andrea; Pani, Roberto [Department of Molecular Medicine, Sapienza University of Rome (Italy); Benlloch Baviera, José María; Talens Aguilar, Albert; Hernandez, Liczandro; Sanchez, Filomeno [Institute for Instrumentation in Molecular Imaging, I3M-CSIC, Valencia (Spain)

    2015-05-18

    In PET detectors based on monolithic scintillators, the photon impact position can be estimated from the light intensity distribution (LD) on the photodetector pixels. Typically, there is a poor estimation of the interaction positions towards the edges when linear algorithms such as Center of Gravity (CoG) are used. We present a novel method to determine the interaction coordinates in thick monolithic crystals filtering the digitized LDs from each gamma-event by means of an autocorrelation filter and the raise to power (RTP) positioning algorithm to reduce the border effects. The experimental setup was based on two detector blocks based on monolithic LYSO scintillator crystals (50x50x20 mm{sup 3}). Each crystal is coupled to a SiPMs array as 12x12 photosensors and an electronic readout that outputs information of each SiPM row and column. Between the detector blocks, a collimated array of 9x9 {sup 22}Na sources, separated 5 mm each other, was placed. The optimum power to use in the RTP positioning algorithm was determined using the third order intercept point (IP3) from plots of the measured coordinates versus known positions. After applying the autocorrelation and RTP fifth to the data, we found an improvement of the spatial resolution from 2.5 mm when CoG is used, to 1.2 mm in the crystal center region. In this work we show how to accurately resolve 3D photon impact coordinates in thick monolithic crystals using autocorrelation filters merged with RTP methods. After applying the new approach it is possible to accurately resolve impacts close to the entrance of 20 mm thick LYSO scintillators. The reached spatial resolution at any photon depth of interaction is comparable with state-of-the-art crystal array approaches with the advantage of the proposed work to also provide continuous depth of interaction information.

  5. Strong ground movement induced by mining activities and its effect on power transmission structures

    Institute of Scientific and Technical Information of China (English)

    DAI Kao-shan; CHEN Shen-en

    2009-01-01

    Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining activities cause strong ground vibrations. Common practice in the power industry is to limit ground motion by specifying maximum Peak Particle Velocity. So far, there is a lack of industry-wide recognized guidelines on how ground vibration limits should be set for the transmission structures. In order to develop a defense strategy to protect power transmission lines against strong ground motions in mining areas, a systematic research work was conducted to establish strong ground vibration characteristics and to study impacts of ground excitations on transmission pole structures. Ground movements were recorded using geophones and wireless tri-axial sensing units. The process of generating ground motion response spectra via analyzing actual ground motion measurements is described in the paper. These spectra developed based on peak particle velocities were used as a basis for spectral analysis performed using validated Finite Element models to obtain structural displacements, reactions and stress states of the transmission pole structures in the mining sites. A quantitative ground motion limit was established by comparing structural responses with the corresponding design requirements.

  6. Collision-Induced Dissociation Mass Spectrometry: A Powerful Tool for Natural Product Structure Elucidation.

    Science.gov (United States)

    Johnson, Andrew R; Carlson, Erin E

    2015-11-03

    Mass spectrometry is a powerful tool in natural product structure elucidation, but our ability to directly correlate fragmentation spectra to these structures lags far behind similar efforts in peptide sequencing and proteomics. Often, manual data interpretation is required and our knowledge of the expected fragmentation patterns for many scaffolds is limited, further complicating analysis. Here, we summarize advances in natural product structure elucidation based upon the application of collision induced dissociation fragmentation mechanisms.

  7. Inspection of Nuclear Power Plant Structures - Overview of Methods and Related Applications

    Energy Technology Data Exchange (ETDEWEB)

    Naus, Dan J [ORNL

    2009-05-01

    The objectives of this limited study were to provide an overview of the methods that are available for inspection of nuclear power plant reinforced concrete and metallic structures, and to provide an assessment of the status of methods that address inspection of thick, heavily-reinforced concrete and inaccessible areas of the containment metallic pressure boundary. In meeting these objectives a general description of nuclear power plant safety-related structures was provided as well as identification of potential degradation factors, testing and inspection requirements, and operating experience; methods for inspection of nuclear power plant reinforced concrete structures and containment metallic pressure boundaries were identified and described; and applications of nondestructive evaluation methods specifically related to inspection of thick-section reinforced concrete structures and inaccessible portions of containment metallic pressure boundaries were summarized. Recommendations are provided on utilization of test article(s) to further advance nondestructive evaluation methods related to thick-section, heavily-reinforced concrete and inaccessible portions of the metallic pressure boundary representative of nuclear power plant containments. Conduct of a workshop to provide an update on applications and needed developments for nondestructive evaluation of nuclear power plant structures would also be of benefit.

  8. Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

    NARCIS (Netherlands)

    De Kanter, J.L.C.G.

    2006-01-01

    Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

  9. Time-based position estimation in monolithic scintillator detectors

    NARCIS (Netherlands)

    Tabacchini, V.; Borghi, G.; Schaart, D.R.

    2015-01-01

    Gamma-ray detectors based on bright monolithic scintillation crystals coupled to pixelated photodetectors are currently being considered for several applications in the medical imaging field. In a typical monolithic detector, both the light intensity and the time of arrival of the earliest

  10. Time-based position estimation in monolithic scintillator detectors

    NARCIS (Netherlands)

    Tabacchini, V.; Borghi, G.; Schaart, D.R.

    2015-01-01

    Gamma-ray detectors based on bright monolithic scintillation crystals coupled to pixelated photodetectors are currently being considered for several applications in the medical imaging field. In a typical monolithic detector, both the light intensity and the time of arrival of the earliest scintilla

  11. Time-based position estimation in monolithic scintillator detectors

    NARCIS (Netherlands)

    Tabacchini, V.; Borghi, G.; Schaart, D.R.

    2015-01-01

    Gamma-ray detectors based on bright monolithic scintillation crystals coupled to pixelated photodetectors are currently being considered for several applications in the medical imaging field. In a typical monolithic detector, both the light intensity and the time of arrival of the earliest scintilla

  12. Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

    NARCIS (Netherlands)

    De Kanter, J.L.C.G.

    2006-01-01

    Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

  13. Hydrogel coated monoliths for enzymatic hydrolysis of penicillin G

    NARCIS (Netherlands)

    De Lathouder, K.M.; Smeltink, M.W.; Straathof, A.J.J.; Paasman, M.A.; Van de Sandt, E.J.A.X.; Kapteijn, F.; Moulijn, J.A.

    2008-01-01

    The objective of this work was to develop a hydrogel-coated monolith for the entrapment of penicillin G acylase (E. coli, PGA). After screening of different hydrogels, chitosan was chosen as the carrier material for the preparation of monolithic biocatalysts. This protocol leads to active immobilize

  14. A new large area monolithic silicon telescope

    CERN Document Server

    Tudisco, S; Cabibbo, M; Cardella, G; De Geronimo, G; Di Pietro, A; Fallica, G; Figuera, P; Musumarra, A; Papa, M; Pappalardo, G S; Rizzo, F; Valvo, G

    1999-01-01

    A new prototype of large area (20x20 mm sup 2) monolithic silicon telescope with an ultrathin DELTA E stage (1 mu m) has been built and tested. A particular mask for the ground electrode has been developed to improve the charge collection reducing the induction between the E and DELTA E stages. A special designed preamplifier has been used for the readout of the signal from the DELTA E stage to overcome the problem of the large input capacitance (40 nF). A rather low energy threshold charge discrimination has been obtained. Small side effects due to the electric field deformation near the ground electrode were observed and quantified.

  15. Monolithic aerogels with nanoporous crystalline phases

    Science.gov (United States)

    Daniel, Christophe; Guerra, Gaetano

    2015-05-01

    High porosity monolithic aerogels with nanoporous crystalline phases can be obtained from syndiotactic polystyrene and poly(2,6-dimethyl-1,4-phenylene)oxide thermoreversible gels by removing the solvent with supercritical CO2. The presence of crystalline nanopores in the aerogels based on these polymers allows a high uptake associated with a high selectivity of volatile organic compounds from vapor phase or aqueous solutions even at very low activities. The sorption and the fast kinetics make these materials particularly suitable as sorption medium to remove traces of pollutants from water and moist air.

  16. Monolithically integrated DBR laser, detector, and transparent waveguide fabricated in a single growth step

    OpenAIRE

    Hofstetter, Daniel; Zappe, H. P.; Epler, J. E.; van Riel, P

    2008-01-01

    The monolithic integration of a GaAs-AlGaAs distributed Bragg reflector (DBR) laser with a nonabsorbing grating section, a transparent waveguide, and an absorbing photodetector is reported. Transparent and absorbing segments were defined after growth by vacancy-enhanced quantum-well disordering (VED). Laser output power was 5 mW with a threshold current of 22 mA. Detector current was linearly dependent on the laser output power and the emission from the grating side of the laser could be dire...

  17. A Monolithic Double-balanced Upconverter for millimeter-wave Point-to-Multipoint Distribution Systems

    OpenAIRE

    Ang, K S; Robertson, I.D.

    2000-01-01

    The design and performance of a monolithic double-balanced upconverter for mm-wave point-to- multipoint distribution systems are presented. Individual building blocks including the LO /RF balun, IF balun,LO /RF power amplifier,and the double- balanced mixer are also fabricated and tested.The complete upconverter,measuring 3x3.2mm,upconverts the 3 -5GHz IF to 40.5 -43.5GHz band with 20 dBm output power.

  18. Effect of Tar-resin Binder on Properties of MgO-C Monolithic Refractories

    Institute of Scientific and Technical Information of China (English)

    Hady EFENDY; Wan Mohd.Farid BIN WAN MOHAMAD

    2010-01-01

    Based on the newly developed bonding system,a new generation of carbon-bonded MgO-C monolithic refractories product with low toxic potential has been developed.Results of an on-going investigation on properties of MgO-C monolithic refractories with tar-resin as binder are presented.Furthermore,the binder is an extremely strong carbon bonding.Further significant advantages of this system are high oxidation resistance of the highly-ordered carbon structure and the excellent stress-absorbing structure.To improve the strength and erosion resistance,and to decrease evaporation during heating,a preliminary treated tar-resin with higher melting temperature and lower content of volatile component was investigated.The binder specimens were treated at 800 ℃ and the mechanical properties of MgO-C refractories specimens treated at 200,400,and 1 200 ℃ were determined.

  19. Position-dependent power spectrum: a new observable in the large-scale structure

    CERN Document Server

    Chiang, Chi-Ting

    2015-01-01

    We present a new observable, position-dependent power spectrum, to measure the large-scale structure bispectrum in the squeezed configuration, where one wavenumber is much smaller than the other two. The squeezed-limit bispectrum measures how the small-scale power spectrum is modulated by a long-wavelength overdensity, which is due to gravitational evolution and possibly inflationary physics. We divide a survey into small subvolumes, compute the local power spectrum and the mean overdensity in each subvolume, and measure the correlation between them. The correlation measures the integral of the bispectrum, which is dominated by squeezed configurations if the scale of the local power spectrum is much smaller than the subvolume size. We use the separate universe approach to model how the small-scale power spectrum is affected by a long-wavelength overdensity gravitationally. This models the nonlinearity of the bispectrum better than the perturbation theory approach. Not only the new observable is easy to interp...

  20. A simple structural power method for determining the vibratory strength of machinery sources

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1998-01-01

    A new simple characterisation of the vibrational source strength of multi-terminal machinery is formulated in terms of a total terminal source power. This single power spectrum is determined from a summation of pairs of mean square velocities and point mobilities of the machine feet. The method...... is tested experimentally for two practical source-receiver configurations. The results clearly demonstrate the simplicity of the method and its high potential for engineering evaluation of machinery source strength and for coarse prediction of power transmission to supporting structures. In principle...... is a constant, frequency independent value, which means that the transmitted power at all frequencies is a constant fraction of the terminal source power spectrum of the machine....

  1. Measurement of the bending wave power flow by the structural intensity technique

    Science.gov (United States)

    Linjama, Jukka; Lahti, Tapio

    1989-02-01

    Literature on the theory of bending waves and power flow, measurement of the structural intensity, and its applications to machinery and buildings is reviewed. Based on intensity measurement equations, a set of frequency domain expressions is derived for bending wave intensity measurements in a beam. A practical procedure for the general 4-transducer method is developed, using the sequential 1-transducer frequency response technique. Expressions for the determination of the force- and moment-related power components separately are derived. In laboratory experiments the power carried by bending waves was measured in a simple beam, and the developed configurations were tested and compared. The frequency response approach to detect the total power flow is shown to work well. The estimation of the force- and moment-related power components, both in the near and the far field, was also demonstrated.

  2. Market power and price structure in the electricity market; Markedsmakt og prisstruktur i kraftmarkedet

    Energy Technology Data Exchange (ETDEWEB)

    Halseth, Arve

    1998-12-01

    This report evaluates the importance of market power on price formation and price structure in the Norwegian electricity market. A simple oligopoly model is used to show how the equilibrium is affected by demand, distribution of capacity between two major suppliers, and marginal production costs, given that the suppliers do not cooperate. Two important conclusions can be drawn from the calculations: (1) a high concentration on the supply side does not necessarily lead to essential market power, and (2) market power may contribute to increased stability and predictability. The main conclusion is that market power can be positive for society and it is not uniquely associated with a high concentration on the supply side. If emphasis is placed on stability and predictability, market power should not be defined as deviation from prices under free competition but rather should be related to the requirement that the suppliers should not obtain unreasonably high profit with unreasonably little utilization of capacity. 10 refs., 11 figs.

  3. On the structure and phase transitions of power-law Poissonian ensembles

    Science.gov (United States)

    Eliazar, Iddo; Oshanin, Gleb

    2012-10-01

    Power-law Poissonian ensembles are Poisson processes that are defined on the positive half-line, and that are governed by power-law intensities. Power-law Poissonian ensembles are stochastic objects of fundamental significance; they uniquely display an array of fractal features and they uniquely generate a span of important applications. In this paper we apply three different methods—oligarchic analysis, Lorenzian analysis and heterogeneity analysis—to explore power-law Poissonian ensembles. The amalgamation of these analyses, combined with the topology of power-law Poissonian ensembles, establishes a detailed and multi-faceted picture of the statistical structure and the statistical phase transitions of these elemental ensembles.

  4. Perturbative power Q^2-corrections to the structure function g(1)

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2006-01-01

    We show that regulating infrared divergencies generates power (\\sim 1/(Q^2)^k) corrections to the spin structure function g_1 at small x. We present the explicit series of such terms as well as the formulae for their resummation. These contributions are not included in the standard analysis of the experimental data. We argue that accounting for such terms can sizably change the impact of the other power corrections conventionally attributed to the higher twists.

  5. Poly(methacrylic acid-ethylene glycol dimethacrylate) monolith in-tube solid phase microextraction coupled to high performance liquid chromatography and analysis of amphetamines in urine samples.

    Science.gov (United States)

    Fan, Yi; Feng, Yu-Qi; Zhang, Jian-Tao; Da, Shi-Lu; Zhang, Min

    2005-05-13

    In-tube solid-phase microextraction (SPME) based on a poly(methacrylic acid-ethylene glycol dimethacrylate) monolithic capillary column was investigated for the extraction of amphetamine, methamphetamine and their methylenedioxy derivatives. The monolithic capillary column showed high extraction efficiency towards target analytes, which could be attributed to its larger loading amount of extraction phase than conventional open-tubular extraction capillaries and the convective mass transfer procedure provided by its monolithic structure. The extraction mechanism was studied, and the results indicated that the extraction process of the target analytes was involved with hydrophobic interaction and ion-exchange interaction. The polymer monolith in-tube SPME-HPLC system with UV detection was successfully applied to the determination of amphetamine, methamphetamine and their methylenedioxy derivatives in urine samples, yielding the detection limits of 1.4 - 4.0 ng/mL. Excellent method reproducibility (RSD urine samples.

  6. Synthesis of a specific monolithic column with artificial recognition sites for L-glutamic acid via cryo-crosslinking of imprinted nanoparticles.

    Science.gov (United States)

    Göktürk, Ilgım; Üzek, Recep; Uzun, Lokman; Denizli, Adil

    2016-06-01

    In this study, a new molecular imprinting (MIP)-based monolithic cryogel column was prepared using chemically crosslinked molecularly imprinted nanoparticles, to achieve a simplified chromatographic separation (SPE) for a model compound, L-glutamic acid (L-Glu). Cryogelation through crosslinking of imprinted nanoparticles forms stable monolithic cryogel columns. This technique reduces the leakage of nanoparticles and increases the surface area, while protecting the structural features of the cryogel for stable and efficient recognition of the template molecule. A non-imprinted monolithic cryogel column (NIP) was also prepared, using non-imprinted nanoparticles produced without the addition of L-Glu during polymerization. The molecularly imprinted monolithic cryogel column (MIP) indicates apparent recognition selectivity and a good adsorption capacity compared to the NIP. Also, we have achieved a significant increase in the adsorption capacity, using the advantage of high surface area of the nanoparticles.

  7. Preparation of poly(N-isopropylacrylamide)-grafted well-controlled 3D skeletal monolith based on E-51 epoxy resin for protein separation.

    Science.gov (United States)

    Xin, Peiyong; Shen, Ying; Qi, Li; Yang, Gengliang; Chen, Yi

    2011-08-15

    A novel type of poly(N-isopropylacrylamide) grafted E-51 epoxy-based monoliths in a 100 mm × 4.6mm I.D. stainless steel column with well-controlled three-dimensional skeletal structures has been prepared and proposed for the separation of proteins. The grafted PNIPAAm chain via surface-initiated atom transfer radical polymerization was successfully performed. The proposed method provided a new route to modify the E-51 epoxy-based monoliths for widening their applications. Meanwhile, the temperature and the salt concentration responses of the grafted monolithic columns were investigated. Under the salt gradient, six proteins were well separated in hydrophobic interaction mode. Moreover, for further confirming the application of the prepared monolith was meaningful for proteome analysis in actual system, the separation of human serum sample was performed.

  8. Are Public-Private Partnerships an Appropriate Governance Structure for Power Plants? A Transaction Cost Analysis

    Science.gov (United States)

    Ho, S. Ping; Hsu, Yaowen

    2015-04-01

    In order to meet the requirements of the rapid economic growth, many countries demand an increasing number of power plants to meet the increasing electricity usage. Since high capital requirements of power plants present a big issue for these countries, PPPs have been considered an alternative to provide power plant infrastructure. In particular, in emerging or developing countries, PPPs may be the fastest way to provide the infrastructure needed. However, while PPPs are a promising alternative to providing various types of infrastructure, many failed power plant PPP projects have made it evident that PPPs, under certain situations, can be very costly or even a wrong choice of governance structure. While the higher efficiency due to better pooling of resources is greatly emphasized in Public-Private Partnerships (PPPs), the embedded transaction inefficiencies are often understated or even ignored. Through the lens of Transaction Cost Economics (TCE), this paper aims to answer why and when PPPs may become a costly governance structure for power plants. Specifically, we develop a TCE-based theory of PPPs as a governance structure. This theory suggests that three major opportunism problems embedded in infrastructure PPPs are possible to cause substantial transaction costs and render PPPs a costly governance structure. The three main opportunism problems are principal-principal problem, firm's hold-up problem, and government-led hold-up problem. Moreover, project and institutional characteristics that may lead to opportunism problems are identified. Based on these characteristics, an opportunism-focused transaction cost analysis (OTCA) for PPPs as a governance structure is proposed to supplement the current practice of PPP feasibility analysis. As a part of theory development, a case study of PPP power plants is performed to evaluate the proposed theory and to illustrate how the proposed OTCA can be applied in practice. Policies and administration strategies for power

  9. An investigation of the thermal properties of hemp and clay monolithic walls

    OpenAIRE

    Busbridge, Ruth; Rhydwen, Ranyl

    2010-01-01

    The monolithic walls of hemp-lime construction enclose and protect a structural timber frame to provide a healthy, breathable building fabric that meets current UK building regulations. It has been proposed that by using hemp as a building material it is possible to actually remove carbon from the atmosphere. Whether or not ‗hemp-crete‘can be considered carbon sequestering, or even neutral, depends largely on the binder. All the lime based binders have high embodied energy, meaning they limit...

  10. Experimental Test of 7.8 GHz Power Extractor Using Dielectric Loaded Rectangular Waveguide Structures

    Institute of Scientific and Technical Information of China (English)

    LU Zhi-Gang; GONG Yu-Bin; GAI Wei; GAO Peng; GAO Feng; WEI Yan- Yu; WANG Wen-Xiang

    2009-01-01

    We report on experimental test of a 7.8 GHz power extractor using a dielectric loaded rectangular waveguide structure. This work is conducted at the Argonne wakefield accelerator (AWA) facility. The wakefield is excited by an electron beam travelling through a dielectric loaded rectangular waveguide, and the generated rf power is then subsequently extracted with a properly designed rf coupler. In the experiment, 30 MW of output power is excited by a 66nC single electron bunch, and wakefield superposition by a train consisting of four bunches is also demonstrated. Both the results agree well with theoretical predictions.

  11. A simple structural power method for determining the vibratory strength of machinery sources

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    1998-01-01

    A new simple characterisation of the vibrational source strength of multi-terminal machinery is formulated in terms of a total terminal source power. This single power spectrum is determined from a summation of pairs of mean square velocities and point mobilities of the machine feet. The method...... is tested experimentally for two practical source-receiver configurations. The results clearly demonstrate the simplicity of the method and its high potential for engineering evaluation of machinery source strength and for coarse prediction of power transmission to supporting structures. In principle...

  12. Changing the adsorption capacity of coal-based honeycomb monoliths for pollutant removal from liquid streams by controlling their porosity

    Energy Technology Data Exchange (ETDEWEB)

    Gatica, Jose M.; Harti, Sanae [Departamento C.M., I.M. y Quimica Inorganica, Universidad de Cadiz, Puerto Real 11510 (Spain); Vidal, Hilario, E-mail: hilario.vidal@uca.es [Departamento C.M., I.M. y Quimica Inorganica, Universidad de Cadiz, Puerto Real 11510 (Spain)

    2010-09-15

    Coal-based honeycomb monoliths extruded using methods developed for ceramic materials have been used to retain methylene blue and p-nitrophenol from aqueous solutions. The influence of the filters' thermal treatment on their textural properties and performance as adsorbents was examined. Characterization by N{sub 2} physisorption, mercury porosimetry and scanning electron microscopy along with adsorption tests under dynamic conditions suggest that, depending on the pollutant and its initial concentration, it can be more convenient to previously submit the monoliths to a simple carbonization or to an additional activation, with or without preoxidation, as a consequence of their different resulting pore structures. Infrared spectroscopy indicates that their different adsorption behaviour seems not to be related to differences in their surface chemical groups. In addition, axial crushing tests show that the monoliths have an acceptable mechanical resistance for the application investigated.

  13. Multi-scale modeling of the heat and mass transfer in a monolithic methane steam-reformer for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, Luis Evelio Garcia; Oliveira, Amir Antonio Martins [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], e-mail: evelio@labcet.ufsc.br, e-mail: amirol@emc.ufsc.br

    2006-07-01

    Here we present a heat and mass transfer analysis for the catalytic methane steam-reforming in a porous monolithic reactor. Thermodynamic analysis provides the bounds for temperature, pressure and steam-methane molar ration for optimum operation. However, the reactor operation is also constrained by chemical kinetics and heat and mass transfer limitations. Porous wash coated monoliths have been used for a long time in the automotive industry as catalytic converters for destruction of gas and particulate pollutants. Here we analyze the modeling issues related to a multi-scale porous structure and develop a model able to assess the advantages and drawbacks of using a monolith as support for a catalyst layer for steam-reforming. (author)

  14. Shamir secret sharing scheme with dynamic access structure (SSSDAS). Case study on nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Thiyagarajan, P.; Thandra, Prasanth Kumar; Rajan, J.; Satyamurthy, S.A.V. [Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam (India). Computer Div.; Aghila, G. [National Institute of Technology, Karaikal (India). Dept. of Computer Science and Engineering

    2015-05-15

    In recent years, due to the sophistication offered by the Internet, strategic organizations like nuclear power plants are linked to the outside world communication through the Internet. The entry of outside world communication into strategic organization (nuclear power plant) increases the hacker's attempts to crack its security and to trace any information which is being sent among the top level officials. Information security system in nuclear power plant is very crucial as even small loophole in the security system will lead to a major disaster. Recent cyber attacks in nuclear power plant provoked information security professionals to look deeply into the information security aspects of strategic organizations (nuclear power plant). In these lines, Shamir secret sharing scheme with dynamic access structure (SSSDAS) is proposed in the paper which provides enhanced security by providing dynamic access structure for each node in different hierarchies. The SSSDAS algorithm can be applied to any strategic organizations with hierarchical structures. In this paper the possible scenarios where SSSDAS algorithm can be applied to nuclear power plant is explained as a case study. The proposed SSSDAS scheme identifies the wrong shares, if any, used for reconstruction of the secret. The SSSDAS scheme also address the three major security parameters namely confidentiality, authentication and integrity.

  15. Collagen-biomorphic porous carbon nanofiber monoliths: Biosilicification-assisted sustainable synthesis and application in Li-S battery

    Science.gov (United States)

    Hu, Wen; Shen, Tao; Hou, Hongying; Gan, Guoyou; Zheng, Biju; Li, Fengxian; Yi, Jianhong

    2016-12-01

    Monolithic carbon has been synthesized via a sustainable biomimetic route utilizing intrafibrillar silicified collagen sponge as precursor and morphogenesis template. The mineralized silica in the biohybrid prevents collapse of the carbon during pyrolysis. Upon biosilica removal results show that the carbon monoliths inherit the porous fiber structure of the mother collagen. The carbon nanofiber framework facilitates the construction of a high electrical conductive pathway, while the internal spaces developed among the intertwined fibrillar network and pores within nanofiber walls offer room for sulfur storage. The as-obtained carbon-sulfur cathode exhibits an accessible discharge capacity approaching 800mAh g-1 in Li-S battery.

  16. Fine structure of high-power microwave-induced resistance oscillations

    Science.gov (United States)

    Shi, Q.; Zudov, M. A.; Dmitriev, I. A.; Baldwin, K. Â. W.; Pfeiffer, L. Â. N.; West, K. Â. W.

    2017-01-01

    We report on observation of a fine structure of microwave-induced resistance oscillations in an ultraclean two-dimensional electron gas. This fine structure is manifested by multiple secondary sharp extrema, residing beside the primary ones, which emerge at high radiation power. Theoretical considerations reveal that this fine structure originates from multiphoton-assisted scattering off short-range impurities. Unique properties of the fine structure allow us to access all experimental parameters, including microwave power, and to separate different contributions to photoresistance. Furthermore, we show that the fine structure offers a convenient means to quantitatively assess the correlation properties of the disorder potential in high-quality systems, allowing separation of short- and long-range disorder contributions to the electron mobility.

  17. Heat transfer and structure stress analysis of micro packaging component of high power light emitting diode

    Directory of Open Access Journals (Sweden)

    Hsu Chih-Neng

    2013-01-01

    Full Text Available This paper focuses on the heat transfer and structural stress analysis of the micro- scale packaging structure of a high-power light emitting diode. The thermal-effect and thermal-stress of light emitting diode are determined numerically. Light emitting diode is attached to the silicon substrate through the wire bonding process by using epoxy as die bond material. The silicon substrate is etched with holes at the bottom and filled with high conductivity copper material. The chip temperature and structure stress increase with input power consumption. The micro light emitting diode is mounted on the heat sink to increase the heat dissipation performance, to decrease chip temperature, to enhance the material structure reliability and safety, and to avoid structure failure as well. This paper has successfully used the finite element method to the micro-scale light emitting diode heat transfer and stress concentration at the edges through etched holes.

  18. Comparing the Topological and Electrical Structure of the North American Electric Power Infrastructure

    CERN Document Server

    Cotilla-Sanchez, Eduardo; Barrows, Clayton; Blumsack, Seth

    2011-01-01

    The topological (graph) structure of complex networks often provides valuable information about the performance and vulnerability of the network. However, there are multiple ways to represent a given network as a graph. Electric power transmission and distribution networks have a topological structure that is straightforward to represent and analyze as a graph. However, simple graph models neglect the comprehensive connections between components that result from Ohm's and Kirchhoff's laws. This paper describes the structure of the three North American electric power interconnections, from the perspective of both topological and electrical connectivity. We compare the simple topology of these networks with that of random (Erdos, 1959), preferential-attachment (Barabasi,1999) and small-world (Watts, 1998) networks of equivalent sizes and find that power grids differ substantially from these abstract models in degree distribution, clustering, diameter and assortativity, and thus conclude that these topological f...

  19. Monolithic columns in plant proteomics and metabolomics.

    Science.gov (United States)

    Rigobello-Masini, Marilda; Penteado, José Carlos Pires; Masini, Jorge Cesar

    2013-03-01

    Since "omics" techniques emerged, plant studies, from biochemistry to ecology, have become more comprehensive. Plant proteomics and metabolomics enable the construction of databases that, with the help of genomics and informatics, show the data obtained as a system. Thus, all the constituents of the system can be seen with their interactions in both space and time. For instance, perturbations in a plant ecosystem as a consequence of application of herbicides or exposure to pollutants can be predicted by using information gathered from these databases. Analytical chemistry has been involved in this scientific evolution. Proteomics and metabolomics are emerging fields that require separation, identification, and quantification of proteins, peptides, and small molecules of metabolites in complex biological samples. The success of this work relies on efficient chromatographic and electrophoretic techniques, and on mass spectrometric detection. This paper reviews recent developments in the use of monolithic columns, focusing on their applications in "top-down" and "bottom-up" approaches, including their use as supports for immobilization of proteolytic enzymes and their use in two-dimensional and multidimensional chromatography. Whereas polymeric columns have been predominantly used for separation of proteins and polypeptides, silica-based monoliths have been more extensively used for separation of small molecules of metabolites. Representative applications in proteomics and in analysis of plant metabolites are given and summarized in tables.

  20. Growth techniques for monolithic YBCO solenoidal magnets

    Energy Technology Data Exchange (ETDEWEB)

    Scruggs, S.J. [Texas Center for Superconductivity at University of Houston, 4800 Calhoun, Houston, TX 77204 (United States)]. E-mail: Sscruggs2@uh.edu; Putman, P.T. [Texas Center for Superconductivity at University of Houston, 4800 Calhoun, Houston, TX 77204 (United States); Fang, H. [Texas Center for Superconductivity at University of Houston, 4800 Calhoun, Houston, TX 77204 (United States); Alessandrini, M. [Texas Center for Superconductivity at University of Houston, 4800 Calhoun, Houston, TX 77204 (United States); Salama, K. [Texas Center for Superconductivity at University of Houston, 4800 Calhoun, Houston, TX 77204 (United States)

    2006-10-01

    The possibility of growing large single domain YBCO solenoids by the use of a large seed has been investigated. There are two known methods for producing a similar solenoid. This first is a conventional top seeded melt growth process followed by a post processing machining step to create the bore. The second involves using multiple seeds spaced around the magnet bore. The appeal of the new technique lies in decreasing processing time compared to the single seed technique, while avoiding alignment problems found in the multiple seeding technique. By avoiding these problems, larger diameter monoliths can be produced. Large diameter monoliths are beneficial because the maximum magnetic field produced by a trapped field magnet is proportional to the radius of the sample. Furthermore, the availability of trapped field magnets with large diameter could enable their use in applications that traditionally have been considered to require wound electromagnets, such as beam bending magnets for particle accelerators or electric propulsion. A comparison of YBCO solenoids grown by the use of a large seed and grown by the use of two small seeds simulating multiple seeding is made. Trapped field measurements as well as microstructure evaluation were used in characterization of each solenoid. Results indicate that high quality growth occurs only in the vicinity of the seeds for the multiple seeded sample, while the sample with the large seeded exhibited high quality growth throughout the entire sample.

  1. Hydrothermal method for preparing calcium phosphate monoliths

    Directory of Open Access Journals (Sweden)

    García Carrodeguas Raúl

    2003-01-01

    Full Text Available A new hydrothermal route for preparing biphasic calcium phosphate monoliths is proposed. Firstly, a slurry of beta-tricalcium phosphate/ortho-phosphoric acid (b-TCP/H3PO4 is cast into the desired final shape and size to obtain a block composed of dicalcium phosphate dihydrate (DCPD and b-TCP. This block is then treated in 1.0 M Na2HPO4 at 60 °C in order to hydrolyze the DCPD into Ca10-x(HPO4x(PO4 6-x(OH2-x (CDHA and Ca8H2(PO46 .5H2O (OCP. The result is a monolithic piece which preserves the initial shape and size, but which is composed instead of CDHA, OCP, and b-TCP. During the initial stage, when the pH is slightly alkaline, the product of DCPD hydrolysis is CDHA. However, when a neutral or slightly acidic pH is reached OCP is formed. Test samples processed by this method showed complete conversion of DCPD into CDHA and OCP after 112 h of hydrolysis, and with a compressive strength of 16.2 MPa, similar to cancellous bone.

  2. Mechanism of Molecular Recognition on Tetrapetide-imprinted Monolith by Capillary Electrochromatography

    Institute of Scientific and Technical Information of China (English)

    ZHENG,Chao; LIU,Zhao-Sheng; GAO,Ru-Yu; ZHANG,Yu-Kui

    2008-01-01

    A tetrapeptide-imprinted capillary monolithic column was synthesized successfully in the presence of YPLG (Tyr-Pro-Leu-Gly) as template by in situ thermo-initiated polymerization. For exploring the recognition mechanism of molecularly imprinted polymer in a capillary electrochromatography (CEC) mode, YPLG and its structural analogue, YPGL (Tyr-Pro-Gly-Leu), differing in amino acid sequence, were used as model compounds. It is hard work to separate the two tetrapeptides by a simple CEC or a capillary electrophoresis mode due to their similar chemical structures and values of pi. However, the results showed that YPLG could be recognized specially by the imprinted monolith. The separation factor (a) and the resolution (Rs) between YPLG and YPGL were 1.73 and 3.72, respectively. The effects of organic modifier concentration, pH value of buffer, salt concentration of buffer and column temperature on the recognition of YPLG and YPGL were investigated. A non-linear Van't Hoff behavior of the template was observed on a YPLG-imprinted column, which suggested the presence of multiple types of retention mechanisms or multiple types of binding sites. The results showed that the molecular recognition on MIP monolith in the CEC mode mainly derived from hydrogen bonding between YPLG and MIP and three-dimensional structure of the imprinting cavities.

  3. Structural Aging Program to evaluate continued performance of safety-related concrete structures in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Naus, D.J.; Oland, C.B. [Oak Ridge National Lab., TN (United States); Ellingwood, B.R. [Johns Hopkins Univ., Baltimore, MD (United States)

    1994-03-01

    This report discusses the Structural Aging (SAG) Program which is being conducted at the Oak Ridge National Laboratory (ORNL) for the United States Nuclear Regulatory commission (USNRC). The SAG Program is addressing the aging management of safety-related concrete structures in nuclear power plants for the purpose of providing improved technical bases for their continued service. The program is organized into three technical tasks: Materials Property Data Base, Structural Component Assessment/Repair Technologies, and Quantitative Methodology for continued Service Determinations. Objectives and a summary of recent accomplishments under each of these tasks are presented.

  4. Mechanical behavior of a Y-TZP ceramic for monolithic restorations: effect of grinding and low-temperature aging

    NARCIS (Netherlands)

    Pereira, G.K.R.; Silvestri, T.; Camargo, R.; Rippe, M.P.; Amaral, M.; Kleverlaan, C.J.; Valandro, L.F.

    2016-01-01

    This study aimed to investigate the effects of grinding with diamond burs and low-temperature aging on the mechanical behavior (biaxial flexural strength and structural reliability), surface topography, and phase transformation of a Y-TZP ceramic for monolithic dental restorations. Disc-shaped speci

  5. Mechanical behavior of a Y-TZP ceramic for monolithic restorations: effect of grinding and low-temperature aging

    NARCIS (Netherlands)

    Pereira, G.K.R.; Silvestri, T.; Camargo, R.; Rippe, M.P.; Amaral, M.; Kleverlaan, C.J.; Valandro, L.F.

    2016-01-01

    This study aimed to investigate the effects of grinding with diamond burs and low-temperature aging on the mechanical behavior (biaxial flexural strength and structural reliability), surface topography, and phase transformation of a Y-TZP ceramic for monolithic dental restorations. Disc-shaped

  6. Vibration transmission through periodic structures using a mobility power flow approach

    Science.gov (United States)

    Cuschieri, J. M.

    1990-01-01

    The transmission of vibrational power (time averaged) through multiple coupled (periodic) structures is examined. The analysis is performed in the frequency domain and the coupling between the sub-elements of the periodic structure is expressed in terms of structural mobility functions for the junction points and between the junction points of the sub-elements. Equal length spans between stiffeners or supports of the periodic structure are considered. Through the use of the mobility power flow approach, the influence of sub-element and junction parameters, including damping at the joints, can be investigated. The results from the analysis can be in the form of either structural intensity or alternatively structural power content for each of the sub-elements. The examples discussed are for a thin, perfectly periodic beam with a finite number of spans with different types of stiffeners and/or supports between the spans. The excitation of the structure is by a point load located midway along the first span.

  7. Nuclear power plant life extension: How aging affects performance of containments & other structures

    Institute of Scientific and Technical Information of China (English)

    Robert A Dameron; Sun Junling

    2013-01-01

    This paper focuses on how aging can affect performance of safety-related structures in nuclear power plant (NPP).Knowledge and assessment of impacts of aging on structures are essential to plant life extension analysis,especially performance to severe loadings such as loss-of-coolant-accidents or major seismic events.Plant life extension issues are of keen interest in countries (like the United States) which have a large,aging fleet of NPPs.This paper addresses the overlap and relationship of structure aging to severe loading performance,with particular emphasis on containment structures.

  8. Preparation of a poly(3'-azido-3'-deoxythymidine-co-propargyl methacrylate-co-pentaerythritol triacrylate) monolithic column by in situ polymerization and a click reaction for capillary liquid chromatography of small molecules and proteins.

    Science.gov (United States)

    Lin, Zian; Yu, Ruifang; Hu, Wenli; Zheng, Jiangnan; Tong, Ping; Zhao, Hongzhi; Cai, Zongwei

    2015-07-01

    Combining free radical polymerization with click chemistry via a copper-mediated azide/alkyne cycloaddition (CuAAC) reaction in a "one-pot" process, a facile approach was developed for the preparation of a poly(3'-azido-3'-deoxythymidine-co-propargyl methacrylate-co-pentaerythritol triacrylate) (AZT-co-PMA-co-PETA) monolithic column. The resulting poly(AZT-co-PMA-co-PETA) monolith showed a relatively homogeneous monolithic structure, good permeability and mechanical stability. Different ratios of monomers and porogens were used for optimizing the properties of a monolithic column. A series of alkylbenzenes, amides, anilines, and benzoic acids were used to evaluate the chromatographic properties of the polymer monolith in terms of hydrophobic, hydrophilic and cation-exchange interactions, and the results showed that the poly(AZT-co-PMA-co-PETA) monolith exhibited more flexible adjustment in chromatographic selectivity than that of the parent poly(PMA-co-PETA) and AZT-modified poly(PMA-co-PETA) monoliths. Column efficiencies for toluene, DMF, and formamide with 35,000-48,000 theoretical plates per m could be obtained at a linear velocity of 0.17 mm s(-1). The run-to-run, column-to-column, and batch-to-batch repeatabilities of the retention factors were less than 4.2%. In addition, the proposed monolith was also applied to efficient separation of sulfonamides, nucleobases and nucleosides, anesthetics and proteins for demonstrating its potential.

  9. Monolithic circuits for barium fluoride detectors used in nuclear physics experiments. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Varner, R.L.; Blankenship, J.L.; Beene, J.R. [Oak Ridge National Lab., TN (United States); Todd, R.A. [RIS Corp., Oak Ridge, TN (United States)

    1998-02-01

    Custom monolithic electronic circuits have been developed recently for large detector applications in high energy physics where subsystems require tens of thousands of channels of signal processing and data acquisition. In the design and construction of these enormous detectors, it has been found that monolithic circuits offer significant advantages over discrete implementations through increased performance, flexible packaging, lower power and reduced cost per channel. Much of the integrated circuit design for the high energy physics community is directly applicable to intermediate energy heavy-ion and electron physics. This STTR project conducted in collaboration with researchers at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory, sought to develop a new integrated circuit chip set for barium fluoride (BaF{sub 2}) detector arrays based upon existing CMOS monolithic circuit designs created for the high energy physics experiments. The work under the STTR Phase 1 demonstrated through the design, simulation, and testing of several prototype chips the feasibility of using custom CMOS integrated circuits for processing signals from BaF{sub 2} detectors. Function blocks including charge-sensitive amplifiers, comparators, one shots, time-to-amplitude converters, analog memory circuits and buffer amplifiers were implemented during Phase 1 effort. Experimental results from bench testing and laboratory testing with sources were documented.

  10. Nonlinear variable structure excitation and steam valving controllers for power system stability

    Institute of Scientific and Technical Information of China (English)

    Ben WANG; Zongyuan MAO

    2009-01-01

    A set of novel nonlinear variable structure excitation and steam-valving controllers are proposed in this paper.On the basis of the classical dynamic equations of a generator,excitation control and steam valving control are si-multaneously considered.Design of these controllers combines the differential geometry theory with the variable structure controlling theory.The mathematical model in the form of "an affine nonlinear system" is set up for the control design of a large-scale power plant.The dynamic performance of the nonlinear variable structure controllers proposed for a single ma-chine connected to an infinite bus power system is simulated.Simulation results show that the nonlinear variable structure excitation and steam-valving controllers give satisfactory dynamic performance and good robustness.

  11. Progress on High Power Tests of Dielectric-Loaded Accelerating Structures

    CERN Document Server

    Jing, Chunguang; Gold, Steven H; Kinkead, Allen; Konecny, Richard; Power, John G

    2005-01-01

    This paper presents a progress report on a series of high-power rf experiments that were carried out to evaluate the potential of the Dielectric-Loaded Accelerating (DLA) structure for high-gradient accelerator operation. Since the last PAC meeting in 2003, we have tested DLA structures loaded with two different ceramic materials: Alumina (Al2O3) and MCT (MgxCa1-xTiO3). The alumina-based DLA experiments have concentrated on the effects of multipactor in the structures under high-power operation, and its suppression using TiN coatings, while the MCT experiments have investigated the dielectric joint breakdown observed in the structures due to local field enhancement. In both cases, physical models have been set up, and the potential engineering solutions are being investigated.

  12. Micro-size antenna structure with vertical nanowires for wireless power transmission and communication.

    Science.gov (United States)

    Kang, Jong-Gu; Jeong, Yeri; Shin, Jeong Hee; Choi, Ji-Woong; Sohn, Jung Inn; Cha, Seung Nam; Jang, Jae Eun

    2014-11-01

    For biomedical implanted devices, a wireless power or a signal transmission is essential to protect an infection and to enhance durability. In this study, we present a magnetic induction technique for a power transmission without any wire connection between transmitter (Tx) and receiver (Rx) in a micro scale. Due to a micro size effect of a flat spiral coil, a magnetic inductance is not high. To enhance the magnetic inductance, a three dimensional magnetic core is added to an antenna structure, which is consisted of ZnO nano wires coated by a nickel (Ni) layer. ZnO nano wires easily supply a large effective surface area with a vertical structural effect to the magnetic core structure, which induces a higher magnetic inductance with a ferro-magnetic material Ni. The magnetic induction antenna with the magnetic core shows a high inductance value, a low reflection power and a strong power transmission. The power transmission efficiencies are tested under the air and the water medium are almost the same values, so that the magnetic induction technique is quite proper to body implanted systems.

  13. Volume structuring of high power LED encapsulates by femtosecond laser direct writing

    Energy Technology Data Exchange (ETDEWEB)

    Kuna, L.; Sommer, C.; Zinterl, E.; Krenn, J.R.; Wenzl, F.P. [Joanneum Research Forschungsges. mbH, Institute of Nanostructured Materials and Photonics, Weiz (Austria); Pachler, P.; Hartmann, P.; Tasch, S. [TridonicAtco Optoelectronics GmbH, Jennersdorf (Austria); Leising, G. [Graz University of Technology, Institute of Solid State Physics, Graz (Austria)

    2008-11-15

    We report on the micro-fabrication of diffractive optical elements (DOEs) such as 1D, 2D and concentric grating structures inside the volume of thin silicone films by femtosecond laser direct writing. In addition, we show that such structures can also be integrated into silicone films that act as encapsulation layers of high power light-emitting diodes. The latter strategy opens new possibilities to homogenize and to control the light emitted from such devices. (orig.)

  14. Preparation and Characterization of Temperature-responsive Porous Monoliths

    Institute of Scientific and Technical Information of China (English)

    ZHANG, Rongyue; QI, Li; XIN, Peiyong; YANG, Gengliang; CHEN, Yi

    2009-01-01

    A new temperature-responsive porous monolith has been prepared by surface-initiated activators generated by electron transfer atom transfer radical polymerization (AGET ATRP) grafting poly(N-isopropylacrylamide) (PNIPAAm) within the pores of the porous polymer monolith. The grafting copolymerization was carried out by a method based on a continuous flow-through technique without special deoxygenation procedure needed in the general ATRP. The addition of ascorbic acid could counteract the oxidation effect of oxygen diffusing into the reaction system. The resulting grafted monolith was characterized by a mercury intrusion method and the size of macropore was 3.65 μm, which was suitable for flow through the monolith for HPLC. The thermally responsive property of the grafted monolith was evaluated by HPLC using steroids with various hydrophobicities as probes. Through determination of retention factor of each steroid on the grafted monolith at different temperatures using water as mobile phase, it was found that the slope of the plot of retention factor of each steroid versus the temperature changed around the low critical solution temperature (LCST, 32 ℃) of PNIPAAm in water. It was relative to the grafted PNIPAAm temperature sensitivity that a hydrophobic and hydrophilic alternation would take place around its LCST.Based on this thermally responsive property, the grafted monolith was used as stationary phase for HPLC and to separate the steroids using water as mobile phase by changing the column temperature. As a mobile phase, water is much better than organic solvents concerning the environment.

  15. A Monolithic High-G SOI-MEMS Accelerometer for Measuring Projectile Launch and Flight Accelerations

    Directory of Open Access Journals (Sweden)

    Bradford S. Davis

    2006-01-01

    Full Text Available Analog Devices (ADI has designed and fabricated a monolithic high-g acceleration sensor (ADXSTC3-HG fabricated with the ADI silicon-on-insulator micro-electro-mechanical system (SOI-MEMS process. The SOI-MEMS sensor structure has a thickness of 10 um, allowing for the design of inertial sensors with excellent cross-axis rejection. The high-g accelerometer discussed in this paper was designed to measure in-plane acceleration to 10,000 g while subjected to 100,000 g in the orthogonal axes. These requirements were intended to meet Army munition applications. The monolithic sensor was packaged in an 8-pin leadless chip carrier (LCC-8 and was successfully demonstrated by the US Army Research Laboratory (ARL as part of an inertial measurement unit during an instrumented flight experiment of artillery projectiles launched at 15,000 g.

  16. A novel monolithic ultraviolet image sensor based on a standard CMOS process

    Institute of Scientific and Technical Information of China (English)

    Li Guike; Feng Peng; Wu Nanjian

    2011-01-01

    We present a monolithic ultraviolet (UV) image sensor based on a standard CMOS process.A compact UV sensitive device structure is designed as a pixel for the image sensor.This UV image sensor consists ofa CMOS pixel array,high-voltage switches,a readout circuit and a digital control circuit.A 16 × 16 image sensor prototype chip is implemented in a 0.18 μm standard CMOS logic process.The pixel and image sensor were measured.Experimental results demonstrate that the image sensor has a high sensitivity of 0.072 V/(mJ/cm2) and can capture a UV image.It is suitable for large-scale monolithic bio-medical and space applications.

  17. A Reliable Method for the Preparation of Multiporous Alumina Monoliths by Ice-Templating

    Directory of Open Access Journals (Sweden)

    Jérémy Dhainaut

    2016-03-01

    Full Text Available Alumina supports presenting a bimodal porosity are generally advantageous for the conversion of bulky molecules such as found in biomass, refining, and petrochemistry. However, shaping of such materials, while controlling pores size and orientation, proves to be hard. This problem can be tackled by using a simple method involving sol-gel chemistry, surfactant self-assembly, and ice-templating. Herein, a systematic study of the formulation and process parameters’ influence on the final material properties is presented. This protocol results in the repeatable preparation of centimeter-sized alumina monoliths presenting a uni-directional macroporosity and structured mesopores. These monoliths should be of particular interest in high flow rate catalytic applications.

  18. Comparison of polystyrene scintillator fiber array and monolithic polystyrene for neutron imaging and radiography

    Science.gov (United States)

    Simpson, R.; Cutler, T. E.; Danly, C. R.; Espy, M. A.; Goglio, J. H.; Hunter, J. F.; Madden, A. C.; Mayo, D. R.; Merrill, F. E.; Nelson, R. O.; Swift, A. L.; Wilde, C. H.; Zocco, T. G.

    2016-11-01

    The neutron imaging diagnostic at the National Ignition Facility has been operating since 2011 generating neutron images of deuterium-tritium (DT) implosions at peak compression. The current design features a scintillating fiber array, which allows for high imaging resolution to discern small-scale structure within the implosion. In recent years, it has become clear that additional neutron imaging systems need to be constructed in order to provide 3D reconstructions of the DT source and these additional views need to be on a shorter line of sight. As a result, there has been increased effort to identify new image collection techniques that improve upon imaging resolution for these next generation neutron imaging systems, such as monolithic deuterated scintillators. This work details measurements performed at the Weapons Neutron Research Facility at Los Alamos National Laboratory that compares the radiographic abilities of the fiber scintillator with a monolithic scintillator, which may be featured in a future short line of sight neutron imaging systems.

  19. Numerical Simulation of Luminescent Downshifting in Top Cell of Monolithic Tandem Solar Cells

    Directory of Open Access Journals (Sweden)

    Mahfoud Abderrezek

    2013-01-01

    Full Text Available The increase in the conversion efficiency of monolithic tandem solar cells is limited by the short-circuit current density matching between the top and the bottom cells. Generally, the top cell presents the lowest current in the two subcells. In this paper, in order to increase the short-circuit current density in the top cell, we present a theoretical survey of the luminescence downshifting (LDS approach for the design of monolithic tandem solar cells. The photovoltaic (PV glass encapsulation material is replaced with a polymer material of polymethyl methacrylate (PMMA type which is doped with diverse kinds of organic dyes. The performance of the n-p-p+ GaInP structure has been simulated as a function of the organic dyes. Gains achieved for the short-circuit current density and conversion efficiency are, respectively, 13.13% and 13.38%, under AM1.5G illumination spectra.

  20. All-metal metamaterial slow-wave structure for high-power sources with high efficiency

    Science.gov (United States)

    Wang, Yanshuai; Duan, Zhaoyun; Tang, Xianfeng; Wang, Zhanliang; Zhang, Yabin; Feng, Jinjun; Gong, Yubin

    2015-10-01

    In this paper, we have proposed a metamaterial (MTM) which is suitable for the compact high-power vacuum electron devices. For example, an S-band slow-wave structure (SWS) based on the all-metal MTMs has been studied by both simulation and experiment. The results show that this MTM SWS is very helpful to miniaturize the high-power vacuum electron devices and largely improve the output power and the electronic efficiency. The simulation model of an S-band MTM backward wave oscillator (BWO) is built, and the particle-in-cell simulated results are presented here: a 2.454 GHz signal is generated and its peak output power is 4.0 MW with a higher electronic efficiency of 31.5% relative to the conventional BWOs.

  1. All-metal metamaterial slow-wave structure for high-power sources with high efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanshuai; Duan, Zhaoyun, E-mail: zhyduan@uestc.edu.cn; Tang, Xianfeng; Wang, Zhanliang; Zhang, Yabin; Gong, Yubin [National Key Laboratory of Science and Technology on Vacuum Electronics in Chengdu, School of Physical Electronics, University of Electronic Science and Technology of China, No. 4, Section 2, North Jianshe Road, Chengdu 610054 (China); Feng, Jinjun [National Key Laboratory of Science and Technology on Vacuum Electronics in Beijing, Beijing Vacuum Electronics Research Institute, Beijing 100015 (China)

    2015-10-12

    In this paper, we have proposed a metamaterial (MTM) which is suitable for the compact high-power vacuum electron devices. For example, an S-band slow-wave structure (SWS) based on the all-metal MTMs has been studied by both simulation and experiment. The results show that this MTM SWS is very helpful to miniaturize the high-power vacuum electron devices and largely improve the output power and the electronic efficiency. The simulation model of an S-band MTM backward wave oscillator (BWO) is built, and the particle-in-cell simulated results are presented here: a 2.454 GHz signal is generated and its peak output power is 4.0 MW with a higher electronic efficiency of 31.5% relative to the conventional BWOs.

  2. Variable Structure Control of DFIG for Wind Power Generation and Harmonic Current Mitigation

    Directory of Open Access Journals (Sweden)

    BELMADANI, B.

    2010-11-01

    Full Text Available This paper focuses on wind energy conversion system (WECS analysis and control for power generation along with problems related to the mitigation of harmonic pollution in the grid using a variable-speed structure control of the doubly fed induction generator (DFIG. A control approach based on the so-called sliding mode control (SMC that is both efficient and suitable is used for power generation control and harmonic-current compensation. The WECS then behaves as an active power filter (APF. The method aims at improving the overall efficiency, dynamic performance and robustness of the wind power generation system. Simulation results obtained on a 20-kW, 380-V, 50-Hz DFIG confirm the effectiveness of the proposed approach.

  3. Organizing and Economic Mechanism for Optimization of Industrial Structure in Electric Power Industry of the Republic of Belarus

    Directory of Open Access Journals (Sweden)

    S. G. Morozov

    2011-01-01

    Full Text Available The paper reveals economic peculiar features of innovative and investment processes in electric power industry. A scheme of organizing and economic mechanism for optimization of the industrial structure in the Belarusian electric power industry has been given in the paper. Realization of the mechanism will promote to better economic efficiency of power generation in the Belarusian power system and diversification of fuel balance of electric power industry.

  4. 51.5 W monolithic single frequency 1.97 μm Tm-doped fiber amplifier

    Institute of Scientific and Technical Information of China (English)

    Xiong; Wang; Pu; Zhou; Xiaolin; Wang; Hu; Xiao; Lei; Si

    2013-01-01

    We demonstrate a monolithic single frequency Tm-doped fiber amplifier with output power of 51.5 W. A single frequency fiber laser at 1.97 μm is amplified by a cascaded master oscillator power amplifier(MOPA) system with all-fiber configuration. The optical-to-optical conversion efficiency of the main fiber amplifier is 45%. No amplified spontaneous emission(ASE) or stimulated Brillouin scattering(SBS) effect is observed in the fiber amplifier. The output power could be further scaled by launching more pump power.

  5. High power RF system for transverse deflecting structure XFEL TDS INJ

    Science.gov (United States)

    Volobuev, E. N.; Zavadtsev, A. A.; Zavadtsev, D. A.; Smirnov, A. J.; Sobenin, N. P.; Churanov, D. V.

    2016-09-01

    The high power RF system (HPRF) is designed for RF feeding of the transverse deflecting structure of the transverse deflecting system XFEL TDS System INJ of the European X-ray Free Electron Laser. The HPRF system includes klystron, waveguide ceramic windows, directional couplers, waveguide vacuum units, spark detector and waveguide line. Operating frequency is 2997.2 MHz. Peak input power is up to 3 MW. The HPRF system has been developed, manufactured and assembled in the XFEL Injector building. The total length of the waveguide line is 55 m from the klystron at the -5 floor to the transverse deflecting structure at the -7 floor. All designed RF parameters have been obtained experimentally at low RF power level.

  6. An Optical Power Divider Based on Two-dimensional Photonic Crystal Structure

    Science.gov (United States)

    Mesri, Nazanin; Alipour-Banaei, Hamed

    2017-05-01

    In this paper, an optical power divider with one input and four outputs has been proposed in a two-dimensional photonic crystal with triangular lattice and simulated using dielectric holes in an air substrate. The dividing properties of the power divider have been numerically simulated and analyzed using the plane wave expansion and finite difference time domain methods. The results show that the transmittance of this divider can be as high as 94.22 % for λ=1.55 µm; thus, the proposed structure is suitable for wavelength division multiplexing communication systems. Also, due to the small footprint of the proposed structure, this optical power divider is applicable for optical-integrated circuit design.

  7. Optimization of a Human-Powered Aircraft Using Fluid–Structure Interaction Simulations

    Directory of Open Access Journals (Sweden)

    Bob Vanderhoydonck

    2016-08-01

    Full Text Available The special type of aircrafts in which the human power of the pilot is sufficient to take off and sustain flight are known as Human-Powered Aircrafts (HPAs. To explore the peculiarities of these aircrafts, the aerodynamic performance of an existing design is evaluated first, using both the vortex lattice method and computational fluid dynamics. In a second step, it is attempted to design and optimize a new HPA capable of winning the Kremer International Marathon Competition. The design will be special in that it allows one to include a second pilot on board the aircraft. As the structural deflection of the wing is found to be a key aspect during design, fluid–structure interaction simulations are performed and included in the optimization procedure. To assess the feasibility of winning the competition, the physical performance of candidate pilots is measured and compared with the predicted required power.

  8. Vacuum-Induced Surface Freezing to Produce Monoliths of Aligned Porous Alumina

    Directory of Open Access Journals (Sweden)

    Sandra Großberger

    2016-12-01

    Full Text Available Vacuum-induced surface freezing has been used to produce uni-directional freezing of colloidal aluminum oxide dispersions. It leads to zones of different structure within the resulting sintered monoliths that are highly similar to those known for freeze casting using a cryogen cold source. A more-or-less dense surface layer and a cellular sub-surface region are formed, beneath which is a middle region of aligned lamellae and pores that stretches through most of the depth of the monolith. This is the case even at a volume fraction of dispersed phase as low as 0.032. A more-dense but still porous base layer is formed by accumulation of rejected nanoparticles preceding the freezing front and differs from previous reports in that no ice lenses are observed. X-ray micro-computed tomography reveals a uniform aligned pore structure vertically through the monolith. The pores close to the periphery are oriented radially or as chords, while the center region contains domains of parallel pores/lamellae. The domains are randomly oriented to one another, as already reported for regular freeze casting. This technique for directional freezing is convenient and easy to perform, but requires further refinement in that the temperature gradient and freezing rates remain yet to be measured. Also, control of the temperature gradient by varying chamber vacuum and shelf temperature needs to be evaluated.

  9. Renormalon Model Predictions for Power-Corrections to Flavour Singlet Deep Inelastic Structure Functions

    CERN Document Server

    Stein, E; Mankiewicz, L; Schäfer, A

    1998-01-01

    We analyze power corrections to flavour singlet deep inelastic scattering structure functions in the framework of the infrared renormalon model. Our calculations, together with previous results for the non-singlet contribution, allow to model the x-dependence of higher twist corrections to F_2, F_L and g_1 in the whole x domain.

  10. GirlPOWER! Strengthening Mentoring Relationships through a Structured, Gender-Specific Program

    Science.gov (United States)

    Pryce, Julia M.; Silverthorn, Naida; Sanchez, Bernadette; DuBois, David L.

    2010-01-01

    The authors examine GirlPOWER! an innovative program that uses structure and group-based activities to enhance one-to-one mentoring relationships for young adolescent girls from the perspective of the focus, purpose, and authorship dimensions of mentoring relationships that Karcher and Nakkula described. The discussion draws on several sources of…

  11. An enhancement of NASTRAN for the seismic analysis of structures. [nuclear power plants

    Science.gov (United States)

    Burroughs, J. W.

    1980-01-01

    New modules, bulk data cards and DMAP sequence were added to NASTRAN to aid in the seismic analysis of nuclear power plant structures. These allow input consisting of acceleration time histories and result in the generation of acceleration floor response spectra. The resulting system contains numerous user convenience features, as well as being reasonably efficient.

  12. Online channel operation mode: Game theoretical analysis from the supply chain power structure

    Directory of Open Access Journals (Sweden)

    Song Huang

    2015-11-01

    Full Text Available Purpose: Dual-channels have been widely used in practice, and the pricing decisions and the online channel operation mode choice have been the core problems in dual-channel supply chain management. This paper focuses on the online channel operation mode choice from the supply chain power structures based on game theoretical analysis. Design/methodology/approach: This paper utilizes three kinds of game theoretical models to analyze the impact of supply chain power structures on the optimal pricing and online channel operation mode choice. Findings: Results derived in this paper indicate that when the self-price elasticity is large, the power structures have no direct impact on the decisions. However, when the self-price elasticity is small and customers’ preference for the online channel is low, then in the MS market, it is better for the retailer to operate the online channel, while in the RS market or in the VN market, it is better for the manufacturer to operate the online channel. Research limitations/implications: In this paper, we do not consider stochastic demand and asymmetric information, which may not well suit the reality. Originality/value: This paper provides a different perspective to analyze the impact of supply chain power structures on the pricing decisions and online channel operation mode choice. The comparison of these two online channel operation modes in this paper is also a unique point.

  13. Theoretical Borderlands: Using Multiple Theoretical Perspectives to Challenge Inequitable Power Structures in Student Development Theory

    Science.gov (United States)

    Abes, Elisa S.

    2009-01-01

    This article is an exploration of possibilities and methodological considerations for using multiple theoretical perspectives in research that challenges inequitable power structures in student development theory. Specifically, I explore methodological considerations when partnering queer theory and constructivism in research on lesbian identity…

  14. Graph Structure in Three National Academic Webs: Power Laws with Anomalies.

    Science.gov (United States)

    Thelwall, Mike; Wilkinson, David

    2003-01-01

    Explains how the Web can be modeled as a mathematical graph and analyzes the graph structures of three national university publicly indexable Web sites from Australia, New Zealand, and the United Kingdom. Topics include commercial search engines and academic Web link research; method-analysis environment and data sets; and power laws. (LRW)

  15. Crack-free polydimethylsiloxane-bioactive glass-poly(ethylene glycol) hybrid monoliths with controlled biomineralization activity and mechanical property for bone tissue regeneration.

    Science.gov (United States)

    Chen, Jing; Du, Yuzhang; Que, Wenxiu; Xing, Yonglei; Chen, Xiaofeng; Lei, Bo

    2015-12-01

    Crack-free organic-inorganic hybrid monoliths with controlled biomineralization activity and mechanical property have an important role for highly efficient bone tissue regeneration. Here, biomimetic and crack-free polydimethylsiloxane (PDMS)-modified bioactive glass (BG)-poly(ethylene glycol) (PEG) (PDMS-BG-PEG) hybrids monoliths were prepared by a facile sol-gel technique. Results indicate that under the assist of co-solvents, BG sol and PDMS and PEG could be hybridized at a molecular level, and effects of the PEG molecular weight on the structure, biomineralization activity, and mechanical property of the as-prepared hybrid monoliths were also investigated in detail. It is found that an addition of low molecular weight PEG can significantly prevent the formation of cracks and speed up the gelation of the hybrid monoliths, and the surface microstructure of the hybrid monoliths can be changed from the porous to the smooth as the PEG molecular weight increases. Additionally, the hybrid monoliths with low molecular weight PEG show the high formation of the biological apatite layer, while the hybrids with high molecular weight PEG exhibit negligible biomineralization ability in simulated body fluid (SBF). Furthermore, the PDMS-BG-PEG 600 hybrid monolith has significantly high compressive strength (32 ± 3 MPa) and modulus (153 ± 11 MPa), as well as good cell biocompatibility by supporting osteoblast (MC3T3-E1) attachment and proliferation. These results indicate that the as-prepared PDMS-BG-PEG hybrid monoliths may have promising applications for bone tissue regeneration.

  16. Preparation of methacrylate-based anion-exchange monolithic microbore column for chromatographic separation of DNA fragments and oligonucleotides

    Energy Technology Data Exchange (ETDEWEB)

    Sabarudin, Akhmad, E-mail: sabarjpn@ub.ac.id [Division of Nano-materials Science, EcoTopia Science Institute, Nagoya University, Furu-Cho, Chikusa-Ku, Nagoya 464-8603 (Japan); Department of Chemistry, Faculty of Science, Brawijaya University, Jl Veteran Malang 65145 (Indonesia); Huang, Junchao; Shu, Shin; Sakagawa, Shinnosuke [Division of Nano-materials Science, EcoTopia Science Institute, Nagoya University, Furu-Cho, Chikusa-Ku, Nagoya 464-8603 (Japan); Umemura, Tomonari, E-mail: umemura@apchem.nagoya-u.ac.jp [Division of Nano-materials Science, EcoTopia Science Institute, Nagoya University, Furu-Cho, Chikusa-Ku, Nagoya 464-8603 (Japan)

    2012-07-29

    Highlights: Black-Right-Pointing-Pointer Microbore-scale (1 mm i.d.) anion-exchange monolithic column. Black-Right-Pointing-Pointer Potentially preparative applications. Black-Right-Pointing-Pointer Separation of oligodeoxythymidylic acids and DNA fragments. - Abstract: In this paper, we report on the preparation of a microbore-scale (1 mm i.d.) anion-exchange monolithic column suitable not only for analytical purposes but also for potentially preparative applications. In order to meet the conflicting requirements of high permeability and good mechanical strength, the following two-step procedure was applied. First, an epoxy-containing monolith was synthesized by in situ copolymerization of glycidyl methacrylate (GMA) and ethylene dimethacrylate (EDMA) within the confines of a silicosteel tubing of 1.02 mm i.d. and 1/16 Double-Prime o.d. in the presence of a ternary porogenic mixture of 1-propanol, 1,4-butanediol, and water. The monolithic matrix was subsequently converted into weak anion-exchanger via the ring-opening reaction of epoxy group with diethyl amine. The dynamic binding capacity was 21.4 mg mL{sup -1} for bovine serum albumin (BSA) at 10% breakthrough. The morphology and porous structure of this monolith were assessed by scanning electron microscope (SEM) and inverse size exclusion chromatography (ISEC). To optimize the separation efficiency, the effects of various chromatographic parameters upon the separation of DNA fragments were investigated. The resulting monolithic anion exchanger demonstrated good potential for the separation of both single- and double-stranded DNA molecules using a gradient elution with NaCl in Tris-HCl buffer (20 mM). Oligodeoxythymidylic acids (dT{sub 12}-dT{sub 18}) were successfully resolved at pH 8, while the fragments of 20 bp DNA ladder, 100 bp DNA ladder, and pBR322-HaeIII digest were efficiently separated at pH 9.

  17. Monolith-Supported Amine-Functionalized Mg2(dobpdc) Adsorbents for CO2 Capture.

    Science.gov (United States)

    Darunte, Lalit A; Terada, Yuri; Murdock, Christopher R; Walton, Krista S; Sholl, David S; Jones, Christopher W

    2017-05-24

    The potential of using an amine-functionalized metal organic framework (MOF), mmen-M2(dobpdc) (M = Mg and Mn), supported on a structured monolith contactor for CO2 capture from simulated flue gas is explored. The stability of the unsupported MOF powders under humid conditions is explored using nitrogen physisorption and X-ray diffraction analysis before and after exposure to humidity. Based on its superior stability to humidity, mmen-Mg2(dobpdc) is selected for further growth on a honeycomb cordierite monolith that is wash-coated with α-alumina. A simple approach for the synthesis of an Mg2(dobpdc) MOF film using MgO nanoparticles as the metal precursor is used. Rapid drying of MgO on the monolith surface followed by a hydrothermal treatment is demonstrated to allow for the synthesis of a MOF film with good crystallite density and favorable orientation of the MOF crystals. The CO2 adsorption behavior of the monolith-supported mmen-Mg2(dobpdc) material is assessed using 10% CO2 in helium and 100% CO2, demonstrating a CO2 uptake of 2.37 and 2.88 mmol/g, respectively. Excellent cyclic adsorption/desorption performance over multiple cycles is also observed. This is one of the first examples of the deployment of an advanced MOF adsorbent in a scalable, low-pressure drop gas-solid contactor. Such demonstrations are critical to the practical application of MOF materials in adsorptive gas separations, as structured contactors have many practical advantages over packed or fluidized beds.

  18. Preliminary comparison of monolithic and aperture optics for XRMF

    Energy Technology Data Exchange (ETDEWEB)

    Havrilla, G.J.; Worley, C.G.

    1997-08-01

    Comparisons between standard aperture optics and a custom designed monolithic capillary x-ray optic for the Kevex Omicron are presented. The results demonstrate the feasibility of retrofitting an Omicron with a monolithic capillary. Increased flux is observed especially at lower energies which results in an increase in sensitivity and potentially an increase in spatial resolution. Alignment is a critical factor in achieving optimal performance of the monolithic capillary. Further improvements in flux output, spot size and overall sensitivity are expected with better alignment.

  19. On monolithic stability and reinforcement analysis of high arch dams

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Monolithic stability safety and reinforcement based on monolithic stability are very important for arch dam design.In this paper,the issue is addressed based on deformation reinforcement theory.In this approach,plastic complementary energy norm can be taken as safety Index for monolithic stability.According to deformation reinforcement theory,the areas where unbalanced force exists require reinforcement,and the required reinforcement forces are just the unbalanced forces with opposite direction.Results show that areas with unbalanced force mainly concentrate in dam-toes,dam-heels and faults.

  20. Preparation of carbon monoliths from orange peel for NOx retention

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo

    2014-12-01

    Full Text Available A series of monoliths are prepared from orange peels and chemically activated with H3PO4, KOH, ZnCl2, and water vapor without a binder. The monoliths were characterized by N2 adsorption-desorption isotherms at 77 K, Boehm titrations and XPS. Thereafter, monoliths were tested for their ability to establish NOx retention. The results show that the retention capacities of NOx were a function of the textural properties and chemistries. The carbons synthesized with ZnCl2 and KOH retained similar amounts of NOx.

  1. A decoupled monolithic projection method for natural convection problems

    Science.gov (United States)

    Pan, Xiaomin; Kim, Kyoungyoun; Lee, Changhoon; Choi, Jung-Il

    2016-06-01

    We propose an efficient monolithic numerical procedure based on a projection method for solving natural convection problems. In the present monolithic method, the buoyancy, linear diffusion, and nonlinear convection terms are implicitly advanced by applying the Crank-Nicolson scheme in time. To avoid an otherwise inevitable iterative procedure in solving the monolithic discretized system, we use a linearization of the nonlinear convection terms and approximate block lower-upper (LU) decompositions along with approximate factorization. Numerical simulations demonstrate that the proposed method is more stable and computationally efficient than other semi-implicit methods, preserving temporal second-order accuracy.

  2. Use of eutectic mixtures for preparation of monolithic carbons with CO₂-adsorption and gas-separation capabilities.

    Science.gov (United States)

    López-Salas, N; Jardim, E O; Silvestre-Albero, A; Gutiérrez, M C; Ferrer, M L; Rodríguez-Reinoso, F; Silvestre-Albero, J; del Monte, F

    2014-10-21

    With global warming becoming one of the main problems our society is facing nowadays, there is an urgent demand to develop materials suitable for CO2 storage as well as for gas separation. Within this context, hierarchical porous structures are of great interest for in-flow applications because of the desirable combination of an extensive internal reactive surface along narrow nanopores with facile molecular transport through broad "highways" leading to and from these pores. Deep eutectic solvents (DESs) have been recently used in the synthesis of carbon monoliths exhibiting a bicontinuous porous structure composed of continuous macroporous channels and a continuous carbon network that contains a certain microporosity and provides considerable surface area. In this work, we have prepared two DESs for the preparation of two hierarchical carbon monoliths with different compositions (e.g., either nitrogen-doped or not) and structure. It is worth noting that DESs played a capital role in the synthesis of hierarchical carbon monoliths not only promoting the spinodal decomposition that governs the formation of the bicontinuous porous structure but also providing the precursors required to tailor the composition and the molecular sieve structure of the resulting carbons. We have studied the performance of these two carbons for CO2, N2, and CH4 adsorption in both monolithic and powdered form. We have also studied the selective adsorption of CO2 versus CH4 in equilibrium and dynamic conditions. We found that these materials combined a high CO2-sorption capacity besides an excellent CO2/N2 and CO2/CH4 selectivity and, interestingly, this performance was preserved when processed in both monolithic and powdered form.

  3. LSST primary/tertiary monolithic mirror

    Science.gov (United States)

    Sebag, J.; Gressler, W.; Liang, M.; Neill, D.; Araujo-Hauck, C.; Andrew, J.; Angeli, G.; Cho, M.; Claver, C.; Daruich, F.; Gessner, C.; Hileman, E.; Krabbendam, V.; Muller, G.; Poczulp, G.; Repp, R.; Wiecha, O.; Xin, B.; Kenagy, K.; Martin, H. M.; Tuell, M. T.; West, S. C.

    2016-08-01

    At the core of the Large Synoptic Survey Telescope (LSST) three-mirror optical design is the primary/tertiary (M1M3) mirror that combines these two large mirrors onto one monolithic substrate. The M1M3 mirror was spin cast and polished at the Steward Observatory Mirror Lab at The University of Arizona (formerly SOML, now the Richard F. Caris Mirror Lab at the University of Arizona (RFCML)). Final acceptance of the mirror occurred during the year 2015 and the mirror is now in storage while the mirror cell assembly is being fabricated. The M1M3 mirror will be tested at RFCML after integration with its mirror cell before being shipped to Chile.

  4. Machining distortion prediction of aerospace monolithic components

    Institute of Scientific and Technical Information of China (English)

    Yun-bo BI; Qun-lin CHENG; Hui-yue DONG; Ying-lin KE

    2009-01-01

    To predict the distortion of aerospace monolithic components.a model is established to simulate the numerical control (NC)milling process using 3D finite element method(FEM).In this model,the cutting layer is simplified firstly.Then,the models of cutting force and cutting temperature are established to gain the cutting loads,which are applied to the mesh model of the part.Finally,a prototype of machining simulation environment is developed to simulate the milling process of a spar.Key factors influencing the distortion,such as initial residual stress,cutting loads,fixture layout,cutting sequence,and tool path are considered all together.The total distortion of the spar is predicted and an experiment is conducted to validate the numerical results.It is found that the maximum discrepancy between the simulation results and experiment values is 19.0%

  5. Solid oxide fuel cell having monolithic core

    Science.gov (United States)

    Ackerman, J. P.; Young, J. E.

    1983-10-01

    A solid oxide fuel cell is described for electrochemically combining fuel and oxidant for generating galvanic output, wherein the cell core has an array of electrolyte and interconnect walls that are substantially devoid of any composite inert materials for support. The core is monolithic, where each electrolyte wall consists of thin layers of cathode and anode materials sandwiching a thin layer of electrolyte material. The electrolyte walls are arranged and backfolded between adjacent interconnect walls operable to define a plurality of core passageways alternately arranged where the inside faces have only the anode material or only the cathode material exposed. Each layer of the electrolyte and interconnect materials 0.002 to 0.01 cm thick; and each layer of the cathode and anode materials is 0.002 to 0.05 cm thick.

  6. Silver deposition on chemically treated carbon monolith

    Directory of Open Access Journals (Sweden)

    Jovanović Zoran M.

    2009-01-01

    Full Text Available Carbon monolith was treated with HNO3, KOH and H2O2. Effects of these treatments on the surface functional groups and on the amount of silver deposited on the CM surface were studied by temperature programmed desorption (TPD and atomic absorption spectrometry (AAS. As a result of chemical treatment there was an increase in the amount of surface oxygen complexes. The increase in the amount of silver deposit is proportional to the amount of surface groups that produce CO under decomposition. However, the high amount of CO groups, decomposing above 600°C, induces the smaller Ag crystallite size. Therefore, the high temperature CO evolving oxides are, most likely, the initial centers for Ag deposition.

  7. Interrelation of structure and operational states in cascading failure of overloading lines in power grids

    Science.gov (United States)

    Xue, Fei; Bompard, Ettore; Huang, Tao; Jiang, Lin; Lu, Shaofeng; Zhu, Huaiying

    2017-09-01

    As the modern power system is expected to develop to a more intelligent and efficient version, i.e. the smart grid, or to be the central backbone of energy internet for free energy interactions, security concerns related to cascading failures have been raised with consideration of catastrophic results. The researches of topological analysis based on complex networks have made great contributions in revealing structural vulnerabilities of power grids including cascading failure analysis. However, existing literature with inappropriate assumptions in modeling still cannot distinguish the effects between the structure and operational state to give meaningful guidance for system operation. This paper is to reveal the interrelation between network structure and operational states in cascading failure and give quantitative evaluation by integrating both perspectives. For structure analysis, cascading paths will be identified by extended betweenness and quantitatively described by cascading drop and cascading gradient. Furthermore, the operational state for cascading paths will be described by loading level. Then, the risk of cascading failure along a specific cascading path can be quantitatively evaluated considering these two factors. The maximum cascading gradient of all possible cascading paths can be used as an overall metric to evaluate the entire power grid for its features related to cascading failure. The proposed method is tested and verified on IEEE30-bus system and IEEE118-bus system, simulation evidences presented in this paper suggests that the proposed model can identify the structural causes for cascading failure and is promising to give meaningful guidance for the protection of system operation in the future.

  8. Technology development on the assessment of structural integrity of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Moon; Choun, Y. S.; Choi, I. K. and others

    1999-04-01

    Nuclear power plants in Korea show drop off in their performance and safety margin as the age of plants increase. The reevaluation of Kori-1 Unit on its performance and safety for life extension is expected in the near future. However, technologies and information related are insufficient to quantitatively estimate them. The final goal of this study is to develop the basic testing and evaluation techniques related with structural integrity of important nuclear equipment and structures. A part of the study includes development of equipment qualification technique. To ensure the structural integrity of structures, systems, and equipment in nuclear power plants, the following 5 research tasks were performed in the first year. - Analysis of dynamic characteristics of reactor internals - Analysis of engineering characteristics of instrumental earthquakes recorded in Korea - Analysis of ultimate pressure capacity and failure mode of containments building - Development of advanced NDE techniques using ultrasonic resonance scattering - Development of equipment qualification technique against vibration aging. These technologies developed in this study can be used to ensure the structural safety of operational nuclear power plants, and for the long-term life management. (author)

  9. Technology development on the assessment of structural integrity of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeong Moon; Choun, Y. S.; Choi, I. K. and others

    1999-04-01

    Nuclear power plants in Korea show drop off in their performance and safety margin as the age of plants increase. The reevaluation of Kori-1 Unit on its performance and safety for life extension is expected in the near future. However, technologies and information related are insufficient to quantitatively estimate them. The final goal of this study is to develop the basic testing and evaluation techniques related with structural integrity of important nuclear equipment and structures. A part of the study includes development of equipment qualification technique. To ensure the structural integrity of structures, systems, and equipment in nuclear power plants, the following 5 research tasks were performed in the first year. - Analysis of dynamic characteristics of reactor internals - Analysis of engineering characteristics of instrumental earthquakes recorded in Korea - Analysis of ultimate pressure capacity and failure mode of containments building - Development of advanced NDE techniques using ultrasonic resonance scattering - Development of equipment qualification technique against vibration aging. These technologies developed in this study can be used to ensure the structural safety of operational nuclear power plants, and for the long-term life management. (author)

  10. Synthesis of PZT power by wet-dry method and its structure

    Institute of Scientific and Technical Information of China (English)

    汤卉; 王佳; 高维丽

    2008-01-01

    To prepare PZT powder at lower temperature, lead zirconate titanate (PZT) powder (x(Zr)/x(Ti)=56?44) was prepared by wet-dry method. Glycol was used as the solvent, and zirconium oxychloride was used as zirconium source. The properties and structure of the powder were analyzed by XRD, SEM and Sedimentograph. The effects of sintering parameter such as sintering temperature, keeping time and heating-up velocity on structure of PZT power were investigated. The results show that homogeneous PZT with single-phase perovskite structure can be obtained after sintering at 730 ℃ for 2 h, and the average size of PZT powder is about 113 nm.

  11. Predicting transmission of structure-borne sound power from machines by including terminal cross-coupling

    DEFF Research Database (Denmark)

    Ohlrich, Mogens

    2011-01-01

    Structure-borne sound generated by audible vibration of machines in vehicles, equipment and house-hold appliances is often a major cause of noise. Such vibration of complex machines is mostly determined and quantified by measurements. It has been found that characterization of the vibratory source......, especially at mid- and high-frequencies. For structurally compact machines, however, the influence of cross-coupling cannot always be ignored. The present paper addresses this problem and examines the transmission of structure-borne sound power by including spatial cross-coupling between pairs...

  12. Energy-filtered Electron Transport Structures for Low-power Low-noise 2-D Electronics.

    Science.gov (United States)

    Pan, Xuan; Qiu, Wanzhi; Skafidas, Efstratios

    2016-10-31

    In addition to cryogenic techniques, energy filtering has the potential to achieve high-performance low-noise 2-D electronic systems. Assemblies based on graphene quantum dots (GQDs) have been demonstrated to exhibit interesting transport properties, including resonant tunnelling. In this paper, we investigate GQDs based structures with the goal of producing energy filters for next generation lower-power lower-noise 2-D electronic systems. We evaluate the electron transport properties of the proposed GQD device structures to demonstrate electron energy filtering and the ability to control the position and magnitude of the energy passband by appropriate device dimensioning. We also show that the signal-to-thermal noise ratio performance of the proposed nanoscale device can be modified according to device geometry. The tunability of two-dimensional GQD structures indicates a promising route for the design of electron energy filters to produce low-power and low-noise electronics.

  13. Monolithic route to efficient dye-sensitized solar cells employing diblock copolymers for mesoporous TiO 2

    KAUST Repository

    Nedelcu, Mihaela

    2010-01-01

    We present a material and device based study on the fabrication of mesoporous TiO2 and its integration into dye-sensitized solar cells. Poly(isoprene-block-ethyleneoxide) (PI-b-PEO) copolymers were used as structure directing agents for the sol-gel based synthesis of nanoporous monolithic TiO2 which was subsequently ground down to small particles and processed into a paste. The TiO2 synthesis and the formation of tens of micrometre thick films from the paste is a scalable approach for the manufacture of dye sensitised solar cells (DSCs). In this study, we followed the self-assembly of the material through the various processing stages of DSC manufacture. Since this approach enables high annealing temperatures while maintaining porosity, excellent crystallinity was achieved. Internal TiO 2 structures ranging from the nanometre to micrometre scale combine a high internal surface area with the strong scattering of light, which results in high light absorption and an excellent full-sun power conversion efficiency of up to 6.4% in a robust, 3 μm thick dye-sensitized solar cell. © 2010 The Royal Society of Chemistry.

  14. Chronic eccentric cycling improves quadriceps muscle structure and maximum cycling power.

    Science.gov (United States)

    Leong, C H; McDermott, W J; Elmer, S J; Martin, J C

    2014-06-01

    An interesting finding from eccentric exercise training interventions is the presence of muscle hypertrophy without changes in maximum concentric strength and/or power. The lack of improvements in concentric strength and/or power could be due to long lasting suppressive effects on muscle force production following eccentric training. Thus, improvements in concentric strength and/or power might not be detected until muscle tissue has recovered (e. g., several weeks post-training). We evaluated alterations in muscular structure (rectus-femoris, RF, and vastus lateralis, VL, thickness and pennation angles) and maximum concentric cycling power (Pmax) 1-week following 8-weeks of eccentric cycling training (2×/week; 5-10.5 min; 20-55% of Pmax). Pmax was assessed again at 8-weeks post-training. At 1 week post-training, RF and VL thickness increased by 24±4% and 13±2%, respectively, and RF and VL pennation angles increased by 31±4% and 13±1%, respectively (all Peccentric cycling can be a time-effective intervention for improving muscular structure and function in the lower body of healthy individuals. The larger Pmax increase detected at 8-weeks post-training implies that sufficient recovery might be necessary to fully detect changes in muscular power after eccentric cycling training.

  15. Multi-source energy harvester to power sensing hardware on rotating structures

    Energy Technology Data Exchange (ETDEWEB)

    Schlichting, Alezander D [Los Alamos National Laboratory; Ouellette, Scott [Los Alamos National Laboratory; Carlson, Clinton P [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory

    2010-01-01

    The U.S. Department of Energy (DOE) proposes to meet 20% of the nation's energy needs through wind power by the year 2030. To accomplish this goal, the industry will need to produce larger (> 100m diameter) turbines to increase efficiency and maximize energy production. It will be imperative to instrument the large composite structures with onboard sensing to provide structural health monitoring capabilities to understand the global response and integrity of these systems as they age. A critical component in the deployment of such a system will be a robust power source that can operate for the lifespan of the wind turbine. In this paper we consider the use of discrete, localized power sources that derive energy from the ambient (solar, thermal) or operational (kinetic) environment. This approach will rely on a multi-source configuration that scavenges energy from photovoltaic and piezoelectric transducers. Each harvester is first characterized individually in the laboratory and then they are combined through a multi-source power conditioner that is designed to combine the output of each harvester in series to power a small wireless sensor node that has active-sensing capabilities. The advantages/disadvantages of each approach are discussed, along with the proposed design for a field ready energy harvester that will be deployed on a small-scale 19.8m diameter wind turbine.

  16. Interarea Power System Oscillations Damping via AI-based Referential Integrity Variable-Structure Control

    Science.gov (United States)

    Ebrahim, M. A.; Ramadan, H. S.

    2016-10-01

    The design of power system stabilizer (PSS) is load-dependent and needs continuous adjustment at each operating condition. This paper aims at introducing a robust non-fragile PSS for interconnected power systems. The proposed controller has the capability of adaptively tuning online its rule-base through a variable-structure direct adaptive control algorithm in order to rigorously attain the desired objectives. The PSS controller acts on damping the electromechanical modes of oscillations not only through a wide range of operating conditions but also in presence of different disturbances. Using MATLABTM-Simulink, simulation results significantly verify that the proposed controller provides favorable performance and efficiently contributes towards enhancing the system dynamic behavior when applied to the four machines two-area power system that mimics the typical system behavior in actual operation. The interaction between the variable-structure adaptive fuzzy-based power system stabilizer (VS-AFPSS) and the existed typical ones inside the interconnected power systems has been explicitly discussed. Compared to other conventional controllers, VS-AFPSS enables better damping characteristics to both local and inter-area oscillation modes considering different operating conditions and sever disturbances.

  17. Monolithic oxide-metal composite thermoelectric generators for energy harvesting

    Science.gov (United States)

    Funahashi, Shuichi; Nakamura, Takanori; Kageyama, Keisuke; Ieki, Hideharu

    2011-06-01

    Monolithic oxide-metal composite thermoelectric generators (TEGs) were fabricated using multilayer co-fired ceramic technology. These devices consisted of Ni0.9Mo0.1 and La0.035Sr0.965TiO3 as p- and n-type thermoelectric materials, and Y0.03Zr0.97O2 was used as an insulator, sandwiched between p- and n-type layers. To co-fire dissimilar materials, p-type layers contained 20 wt. % La0.035Sr0.965TiO3; thus, these were oxide-metal composite layers. The fabricated device had 50 pairs of p-i-n junctions of 5.9 mm × 7.0 mm × 2.6 mm. The calculated maximum value of the electric power output from the device was 450 mW/cm2 at ΔT = 360 K. Furthermore, this device generated 100 μW at ΔT = 10 K and operated a radio frequency (RF) transmitter circuit module assumed to be a sensor network system.

  18. Study of the influential leaders, power structure, community decisions, and geothermal energy development in Imperial County, California

    Energy Technology Data Exchange (ETDEWEB)

    Butler, E.W.; Hall, C.H.; Pick, J.B.

    1980-04-01

    The economy of Imperial County, California, is now dominated by agriculture, but economic studies indicate that the emerging geothermal sector could grow to a size comparable to that of agriculture. The purpose of this study is to discover the kind of power structure operating in Imperial County, the influential leaders, the source of their power, their probable reactions to geothermal development, and the possible effects geothermal development will have on the power structure. Several social science research methods are used to identify the influential leaders and to describe the power structure in Imperial County. An analysis of the opinions of leadership and the public shows the likely response to geothermal development. The power structure analysis, combined with forecasts of the economic effects of geothermal development, indicates the ways in which the power structure itself may change.

  19. Biosonar resolving power: Echo-acoustic perception of surface structures in the submillimeter range

    Directory of Open Access Journals (Sweden)

    Ralph eSimon

    2014-02-01

    Full Text Available The minimum distance for which two points still can be separated from each other defines the resolving power of a visual system. In an echo-acoustic context, the resolving power is usually measured as the smallest perceivable distance of two reflecting surfaces on the range axis and is found to be around half a millimetre for bats employing frequency modulated echolocation calls. Only few studies measured such thresholds with physical objects, most often bats were trained on virtual echoes i.e. echoes generated and played back by a computer; moreover, bats were sitting while they received the stimuli. In these studies differences in structure depth between 200 µm and 340 µm were found. However, these low thresholds were never verified for free-flying bats and real physical objects. Here, we show behavioural evidence that the echo-acoustic resolving power for surface structures in fact can be as low as measured for computer generated echoes and even lower, sometimes below 100 µm. We found this exceptional fine discrimination ability only when one of the targets showed spectral interferences in the frequency range of the bats' echolocation call while the other target did not. This result indicates that surface structure is likely to be perceived as a spectral quality rather than being perceived strictly in the time domain. Further, it points out that sonar resolving power directly depends on the highest frequency/shortest wavelength of the signal employed.

  20. A variable structure unified power flow controller for advanced industrial application

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T.-T.

    2004-07-01

    This paper presents a new application example of flexible ac transmission systems (FACTS) devices in the advanced industrial power control schemes. An integrated multi-functional power quality controller and energy saving system based on the unified power flow controller (UPFC) is proposed. The proposed integrated system can compensate the reactive power, harmonic current and the unbalanced power of the controlled distribution system with a capacity-limitation manner by its shunt branch. It also can regulate multiple load voltages simultaneously based on the prescribed P-V characteristics of distinct loads for the purpose of energy saving via its series branch. The detailed design procedure of the controllers providing flexible hardware configuration and multiple control functions is presented. A 15 KVA test-system with the variable structure UPFC configuration performing active power filter functions and simultaneously regulating an 7HP induction motor for energy saving is numerically investigated with EMTP programs. The feasibility and effectiveness of the proposed system and the related control techniques are confirmed through some simulation results. (author)

  1. Perturbative Q{sup 2}-power corrections to the structure function g{sub 1}

    Energy Technology Data Exchange (ETDEWEB)

    Ermolaev, B.I. [Ioffe Physico-Technical Institute, St. Petersburg (Russian Federation); Greco, M. [Dipartimento di Fisica, Roma (Italy); INFN, Roma (Italy); Troyan, S.I. [St. Petersburg Institute of Nuclear Physics, Gatchina (Russian Federation)

    2007-08-15

    We show that ({proportional_to}1/(Q{sup 2}){sup k}) power corrections to the spin structure function g{sub 1} at small x are generated perturbatively from the regulated infrared divergencies. We present the explicit series of such terms as well as the formulae for their resummation. These contributions are not included in the standard analysis of the experimental data. We argue that accounting for such terms can sizably change the impact of the power corrections conventionally attributed to the higher twists. (orig.)

  2. Improved Structure and Fabrication of Large, High-Power KHPS Rotors - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Corren, Dean [Verdant Power, Inc.; Colby, Jonathan [Verdant Power, Inc.; Adonizio, Mary Ann [Verdant Power, Inc.

    2013-01-29

    Verdant Power, Inc, working in partnership with the National Renewable Energy Laboratory (NREL), Sandia National Laboratories (SNL), and the University of Minnesota St. Anthony Falls Laboratory (SAFL), among other partners, used evolving Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) models and techniques to improve the structure and fabrication of large, high-power composite Kinetic Hydropower System (KHPS) rotor blades. The objectives of the project were to: design; analyze; develop for manufacture and fabricate; and thoroughly test, in the lab and at full scale in the water, the improved KHPS rotor blade.

  3. Passivity-Based Nonlinear Excitation Control of Power Systems with Structure Matrix Reassignment

    Directory of Open Access Journals (Sweden)

    Bing Chu

    2013-08-01

    Full Text Available Passivity-based control is widely used in electronic circuit systems because it can utilize their internal structures to facilitate the controller design. In this paper, we first propose a dissipative Hamiltonian realization of power systems and discuss the disadvantages of the traditional passivity-based excitation controller. Then, a novel excitation controller is put forward to reassign the interconnection and dissipative matrix, and the corresponding Hamiltonian function. Simulation results verify that the proposed controller can effectively improve the transient stability of the power system.

  4. Misalignment tolerable coil structure for biomedical applications with wireless power transfer.

    Science.gov (United States)

    Chow, Jeff P W; Chen, Nan; Chung, Henry S H; Chan, Leanne L H

    2013-01-01

    Coil-misalignment is one of the major hurdles for inductively coupled wireless power transfer in applications like retinal prosthesis. Weak magnetic flux linkage due to coil misalignments would significantly impair the power efficiency. A novel receiver configuration with high misalignment tolerance is presented in this paper. The proposed receiver is composed of two receiver coils placed orthogonally, so as to reduce the variation of mutual inductance between transmitting and receiving coils under misalignment conditions. Three different receiver coil structures are analyzed and compared using the same length of wire. Theoretical predictions have been confirmed with measurement results.

  5. Passively Q-switched diode-pumped Cr4+:YAG/Nd3+:GdVO4 monolithic microchip laser

    CERN Document Server

    Forget, S; Balembois, F; Georges, P; Landru, N; Feve, J P; Lin, J; Weng, Z; Forget, Sebastien; Druon, Frederic; Balembois, Francois; Georges, Patrick; Landru, Nicolas; Feve, Jean Philippe; Lin, Jiali; Weng, Zhiming

    2006-01-01

    the realization of high repetition rate passively Q-switched monolithic microlaser is a challenge since a decade. To achieve this goal, we report here on the first passively Q-switched diode-pumped microchip laser based on the association of a Nd:GdVO4 crystal and a Cr4+:YAG saturable absorber. The monolithic design consists of 1 mm long 1% doped Nd:GdVO4 optically contacted on a 0.4 mm long Cr4+:YAG leading to a plano-plano cavity. A repetition rate as high as 85 kHz is achieved. The average output power is approximately 400 mW for 2.2 W of absorbed pump power and the pulse length is 1.1 ns.

  6. Textural characterization of native and n-alky-bonded silica monoliths by mercury intrusion/extrusion, inverse size exclusion chromatography and nitrogen adsorption.

    Science.gov (United States)

    Thommes, M; Skudas, R; Unger, K K; Lubda, D

    2008-05-16

    Native and n-alkyl-bonded (n-octadecyl) monolithic silica rods with mesopores in the range between 10 and 25 nm and macropores in the range between 1.8 and 6.0 microm were examined by mercury intrusion/extrusion, inverse size exclusion chromatography (ISEC) and nitrogen sorption. Our results reveal very good agreement for the mesopore size distribution obtained from nitrogen adsorption (in combination with an advanced NLDFT analysis) and ISEC. Our studies highlight the importance of mercury porosimetry for the assessment of the macropore size distribution and show that mercury porosimetry is the only method which allows obtaining a combined and comprehensive structural characterization of macroporous/mesoporous silica monoliths. Our data clearly confirm that mercury porosimetry hysteresis and entrapment have different origin, and indicate the intrinsic nature of mercury porosimetry hysteresis in these silica monoliths. Within this context some silica monoliths show the remarkable result of no entrapment of mercury after extrusion from the mesopore system (i.e. for the first intrusion/extrusion cycle). The results of a systematic study of the mercury intrusion/extrusion behavior into native silica monoliths and monoliths with bonded n-alkyl groups reveals that the macro (through) pore structure, which controls the mass transfer to and from the mesopores, here mainly controls the entrapment behavior. Our data suggest that mercury intrusion/extrusion porosimetry does not only allow to obtain a comprehensive pore structure analysis, but can also serve as a tool to estimate the mass transport properties of silica monoliths to be employed in liquid-phase separation processes.

  7. Monolithic Rare Earth Doped PTR Glass Laser Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The main goal of the project is to demonstrate the feasibility of a monolithic solid state laser on the basis of PTR glass co-doped with luminescent rare earth ions....

  8. Monolithic Perovskite Silicon Tandem Solar Cells with Advanced Optics

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, Jan C.; Bett, Alexander J.; Bivour, Martin; Blasi, Benedikt; Eisenlohr, Johannes; Kohlstadt, Markus; Lee, Seunghun; Mastroianni, Simone; Mundt, Laura; Mundus, Markus; Ndione, Paul; Reichel, Christian; Schubert, Martin; Schulze, Patricia S.; Tucher, Nico; Veit, Clemens; Veurman, Welmoed; Wienands, Karl; Winkler, Kristina; Wurfel, Uli; Glunz, Stefan W.; Hermle, Martin

    2016-11-14

    For high efficiency monolithic perovskite silicon tandem solar cells, we develop low-temperature processes for the perovskite top cell, rear-side light trapping, optimized perovskite growth, transparent contacts and adapted characterization methods.

  9. Effect of accelerated aging on translucency of monolithic zirconia

    Directory of Open Access Journals (Sweden)

    O. Abdelbary

    2016-12-01

    Conclusion: Thickness of zirconia has significant effect on translucency. Aging has significant effect on thinner sections of zirconia. More research is required on zirconia towards making the material more translucent for its potential use as esthetic monolithic restoration.

  10. Monolithic CMOS pixel detector for international linear collider vertex detection

    Indian Academy of Sciences (India)

    J E Brau; O Igonkina; N Sinew; D Strom; C Baltay; W Emmet; H Neal; D Rabinowitz

    2007-12-01

    A monolithic CMS pixel detector is under development for an ILC experiment. This chronopixel array provides a time stamp resolution of one bunch crossing, a critical feature for background suppression. The status of this effort is summarized.

  11. A design concept for an MMIC (Monolithic Microwave Integrated Circuit) microstrip phased array

    Science.gov (United States)

    Lee, Richard Q.; Smetana, Jerry; Acosta, Roberto

    1987-02-01

    A conceptual design for a microstrip phased array with monolithic microwave integrated circuit (MMIC) amplitude and phase controls is described. The MMIC devices used are 20 GHz variable power amplifiers and variable phase shifters recently developed by NASA contractors for applications in future Ka proposed design, which concept is for a general NxN element array of rectangular lattice geometry. Subarray excitation is incorporated in the MMIC phased array design to reduce the complexity of the beam forming network and the number of MMIC components required.

  12. A 1.55-μm laser array monolithically integrated with an MMI combiner

    Institute of Scientific and Technical Information of China (English)

    Ma Li; Zhu Hongliang; Liang Song; Wang Baojun; Zhang Can; Zhao Lingjuan; Bian Jing

    2013-01-01

    The monolithic integration of four 1.55-μm range InGaAsP/InP distributed feedback lasers with a 4 × 1multimode-interference (MMI) optical combiner using the varied width ridge method is proposed and demonstrated.The average output power is 1.5 mW when the current of LD is 100 mA and the threshold current is 30-35 mA at 25 ℃.The lasing wavelength is 1.55-μm range and 40 dB sidemode suppression ratio is obtained.The four channels can operate separately or simultaneously.

  13. MuPix7 - A fast monolithic HV-CMOS pixel chip for Mu3e

    CERN Document Server

    Augustin, H; Dittmeier, S; Hammerich, J; Hartenstein, U; Huang, Q; Huth, L; Immig, D; Kozlinskiy, A; Aeschbacher, F Meier; Perić, I; Perrevoort, A -K; Schöning, A; Shrestha, S; Sorokin, I; Tyukin, A; Bruch, D vom; Wauters, F; Wiedner, D; Zimmermann, M

    2016-01-01

    The MuPix7 chip is a monolithic HV-CMOS pixel chip, thinned down to 50 \\mu m. It provides continuous self-triggered, non-shuttered readout at rates up to 30 Mhits/chip of 3x3 mm^2 active area and a pixel size of 103x80 \\mu m^2. The hit efficiency depends on the chosen working point. Settings with a power consumption of 300 mW/cm^2 allow for a hit efficiency >99.5%. A time resolution of 14.2 ns (Gaussian sigma) is achieved. Latest results from 2016 test beam campaigns are shown.

  14. Laser-diode-pumped 1319-nm monolithic non-planar ring single-frequency laser

    Institute of Scientific and Technical Information of China (English)

    Qing Wang(王青); Chunqing Gao(高春清); Yan Zhao(赵严); Suhui Yang(杨苏辉); Guanghui Wei(魏光辉); Dongmei Hong(洪冬梅)

    2003-01-01

    Single-frequency 1319-nm laser was obtained by using a laser-diode-pumped monolithic Nd:YAG crystalwith a non-planar ring oscillator (NPRO). When the NPRO laser was pumped by an 800-μm fiber coupledlaser diode, the output power of the single-frequency 1319-nm laser was 220 mW, and the slope efficiencywas 16%. With a 100-μm fiber coupled diode laser pumped, 99-mW single-frequency 1319-nm laser wasobtained with a slope efficiency of 29%.

  15. A design concept for an MMIC (Monolithic Microwave Integrated Circuit) microstrip phased array

    Science.gov (United States)

    Lee, Richard Q.; Smetana, Jerry; Acosta, Roberto

    1987-01-01

    A conceptual design for a microstrip phased array with monolithic microwave integrated circuit (MMIC) amplitude and phase controls is described. The MMIC devices used are 20 GHz variable power amplifiers and variable phase shifters recently developed by NASA contractors for applications in future Ka proposed design, which concept is for a general NxN element array of rectangular lattice geometry. Subarray excitation is incorporated in the MMIC phased array design to reduce the complexity of the beam forming network and the number of MMIC components required.

  16. Design of a monolithic tunable laser based on equivalent-chirp grating reflectors.

    Science.gov (United States)

    Dai, Yitang; Xu, Kun; Wu, Jian; Li, Yan; Hong, Xiaobin; Guo, Hongxiang; Lin, Jintong

    2010-12-01

    A Vernier-tuned distributed Bragg reflector (DBR) semiconductor laser is an effective monolithic approach for wide wavelength tunability, at the expense, however, of costly electron-beam lithography during fabrication. In this Letter, a tunable laser design with equivalent-chirp based, flat-top envelope grating reflectors is proposed that can be implemented easily by conventional two-beam interference lithography. The principle is described, and a detailed design shows uniform output power (0.08 dB variation) and excellent side-mode suppression ratio (47 dB minimum) within a wide tuning range (>32 nm) through numerical simulation.

  17. InAs/GaAs quantum-dot superluminescent diodes monolithically grown on a Ge substrate.

    Science.gov (United States)

    Jiang, Qi; Tang, Mingchu; Chen, Siming; Wu, Jiang; Seeds, Alwyn; Liu, Huiyun

    2014-09-22

    We report the first InAs/GaAs quantum-dot (QD) superluminescent diode (SLD) monolithically grown on a Ge substrate by molecular beam epitaxy. The QD SLD exhibits a 3 dB emission bandwidth of ~60 nm centered at 1252 nm with output power of 27 mW at room temperature. The 3 dB bandwidth is very stable over the temperature range from 20 °C to 100 °C, which highlights the potential for integration with high performance ICs.

  18. Synthesis of monolithic graphene – graphite integrated electronics

    Science.gov (United States)

    Park, Jang-Ung; Nam, SungWoo; Lee, Mi-Sun; Lieber, Charles M.

    2013-01-01

    Encoding electronic functionality into nanoscale elements during chemical synthesis has been extensively explored over the past decade as the key to developing integrated nanosystems1 with functions defined by synthesis2-6. Graphene7-12 has been recently explored as a two-dimensional nanoscale material, and has demonstrated simple device functions based on conventional top-down fabrication13-20. However, the synthetic approach to encoding electronic functionality and thus enabling an entire integrated graphene electronics in a chemical synthesis had not previously been demonstrated. Here we report an unconventional approach for the synthesis of monolithically-integrated electronic devices based on graphene and graphite. Spatial patterning of heterogeneous catalyst metals permits the selective growth of graphene and graphite, with controlled number of graphene layers. Graphene transistor arrays with graphitic electrodes and interconnects were formed from synthesis. These functional, all-carbon structures were transferrable onto a variety of substrates. The integrated transistor arrays were used to demonstrate real-time, multiplexed chemical sensing, and more significantly, multiple carbon layers of the graphene-graphite device components were vertically assembled to form a three-dimensional flexible structure which served as a top-gate transistor array. These results represent a substantial progress towards encoding electronic functionality via chemical synthesis and suggest future promise for one-step integration of graphene-graphite based electronics. PMID:22101813

  19. Synthesis of monolithic graphene-graphite integrated electronics.

    Science.gov (United States)

    Park, Jang-Ung; Nam, SungWoo; Lee, Mi-Sun; Lieber, Charles M

    2011-11-20

    Encoding electronic functionality into nanoscale elements during chemical synthesis has been extensively explored over the past decade as the key to developing integrated nanosystems with functions defined by synthesis. Graphene has been recently explored as a two-dimensional nanoscale material, and has demonstrated simple device functions based on conventional top-down fabrication. However, the synthetic approach to encoding electronic functionality and thus enabling an entire integrated graphene electronics in a chemical synthesis had not previously been demonstrated. Here we report an unconventional approach for the synthesis of monolithically integrated electronic devices based on graphene and graphite. Spatial patterning of heterogeneous metal catalysts permits the selective growth of graphene and graphite, with a controlled number of graphene layers. Graphene transistor arrays with graphitic electrodes and interconnects were formed from the synthesis. These functional, all-carbon structures were transferable onto a variety of substrates. The integrated transistor arrays were used to demonstrate real-time, multiplexed chemical sensing and more significantly, multiple carbon layers of the graphene-graphite device components were vertically assembled to form a three-dimensional flexible structure which served as a top-gate transistor array. These results represent substantial progress towards encoding electronic functionality through chemical synthesis and suggest the future promise of one-step integration of graphene-graphite based electronics.

  20. Preparation of macroporous methacrylate-based monoliths for chromatographic applications by the Reactive Gelation Process.

    Science.gov (United States)

    Bechtle, M; Butté, A; Storti, G; Morbidelli, M

    2010-07-09

    Polymeric monoliths are a relatively new separation medium for chromatographic applications. The innovative approach to produce such monoliths, the Reactive Gelation Process, presented by Marti et al. [1] for polystyrene macroporous materials is applied to a methacrylate-based material. It is shown that it is possible to create a macroporous structure by Reactive Gelation also with this polymer even if the properties of the material are different. Besides the analysis of the material by SEM and BET, several chromatographic methods are used to analyze the material properties. The ISEC experiments showed a much smaller size exclusion effect than in conventional packed beds. The permeability of the material is comparable to a packed bed with 4.13 μm particles. The column efficiency is not changing for increasing flow rates. Because of the high efficiency of the material, shorter columns are needed and therefore the comparatively low permeability is compensated. The monolith also exhibits a significant adsorption capacity for hydrophobic interaction, which makes it suitable for chromatographic purification processes.