Eichinger, R. A.; Dachel, P.; Miller, W. H.; Ingold, J. S.
1982-01-01
Extremely low noise, high performance, wideband buffer amplifiers and buffered phase comparators were developed. These buffer amplifiers are designed to distribute reference frequencies from 30 KHz to 45 MHz from a hydrogen maser without degrading the hydrogen maser's performance. The buffered phase comparators are designed to intercompare the phase of state of the art hydrogen masers without adding any significant measurement system noise. These devices have a 27 femtosecond phase stability floor and are stable to better than one picosecond for long periods of time. Their temperature coefficient is less than one picosecond per degree C, and they have shown virtually no voltage coefficients.
International Nuclear Information System (INIS)
Kawakami, S.; Yamanaka, Y.; Kato, K.; Asano, H.; Ueda, H.
1999-01-01
The methods of fabrication, handling, and emplacement of engineered barriers used in a deep geological repository for high level radioactive waste should be planned as simply as possible from the engineering and economic viewpoints. Therefore, a new concept of a monolithic buffer material around a waste package have been proposed instead of the conventional concept with the use of small blocks, which would decrease the cost for buffer material. The monolithic buffer material is composed of two parts of highly compacted bentonite, a cup type body and a cover. As the forming method of the monolithic buffer material, compaction by the cold isostatic pressing process (CIP) has been employed. In this study, monolithic bentonite bodies with the diameter of about 333 mm and the height of about 455 mm (corresponding to the approx. 1/5 scale for the Japanese reference concept) were made by the CIP of bentonite powder. The dry densities: ρd of the bodies as a whole were measured and the small samples were cut from several locations to investigate the density distribution. The swelling pressure and hydraulic conductivity as function of the monolithic body density for CIP-formed specimens were also measured. High density (ρd: 1.4--2.0 Mg/m 3 ) and homogeneous monolithic bodies were formed by the CIP. The measured results of the swelling pressure (3--15 MPa) and hydraulic conductivity (0.5--1.4 x 10 -13 m/s) of the specimens were almost the same as those for the uniaxial compacted bentonite in the literature. It is shown that the vacuum hoist system is an applicable handling method for emplacement of the monolithic bentonite
Development and applications of femtosecond monolithic Yb-doped fiber chirped-pulse amplifiers
International Nuclear Information System (INIS)
Zhu, L.
2011-01-01
In the past few years, compact and environmentally stable high-energy ultrashort pulse laser sources have been broadly utilized in many different applications. Fiber lasers offer big practical advantages over bulk solid-state laser systems in terms of flexibility, compactness, reliability, cost effectiveness and turn-key operability. Moreover, thermal effects are dramatically reduced due to the large surface-to-volume ratio of an optical fiber, and good spatial mode quality can be ensured by its waveguiding property. Therefore, a fiber-based laser system is considered to be the preferred laser architecture. The main theme of this thesis is the development of various femtosecond monolithic Yb-doped fiber chirped-pulse-amplification (FCPA) system and their applications. We demonstrate an ultrafast high-energy monolithic Yb-doped FCPA system in which the pulse fidelity is preserved by weakening the nonlinear effects via a substantial level of temporal stretching of the seed pulses and by using highly doped active fibers as amplifying media. The presented monolithic FCPA delivers up to ∼ 25 μJ diffraction-limited pulses that can be recompressed to sub-200 fs duration, and the pulse quality has been confirmed through the second-harmonic-generation (SHG) conversion efficiency of over 52%. Improved dispersion and nonlinearity management schemes of the FCPA system allowing substantial pulse energy scaling in the monolithic format as well as methods for overcoming a series of technological challenges are reported. Three different types of Yb-doped fiber oscillators have been developed and built in the course of this PhD work. First, we compare two oscillator types that are based on the all-normal-dispersion (ANDi) regime and the dispersion-managed (DM) regime. Both of them have been tested as the seed-pulse source of the monolithic Yb-doped FCPA system. Then we introduce another novel design based on higher-order-mode (HOM) dispersion management that competes with a
NASA developments in solid state power amplifiers
Leonard, Regis F.
1990-01-01
Over the last ten years, NASA has undertaken an extensive program aimed at development of solid state power amplifiers for space applications. Historically, the program may be divided into three phases. The first efforts were carried out in support of the advanced communications technology satellite (ACTS) program, which is developing an experimental version of a Ka-band commercial communications system. These first amplifiers attempted to use hybrid technology. The second phase was still targeted at ACTS frequencies, but concentrated on monolithic implementations, while the current, third phase, is a monolithic effort that focusses on frequencies appropriate for other NASA programs and stresses amplifier efficiency. The topics covered include: (1) 20 GHz hybrid amplifiers; (2) 20 GHz monolithic MESFET power amplifiers; (3) Texas Instruments' (TI) 20 GHz variable power amplifier; (4) TI 20 GHz high power amplifier; (5) high efficiency monolithic power amplifiers; (6) GHz high efficiency variable power amplifier; (7) TI 32 GHz monolithic power amplifier performance; (8) design goals for Hughes' 32 GHz variable power amplifier; and (9) performance goals for Hughes' pseudomorphic 60 GHz power amplifier.
Monolithic integration of SOI waveguide photodetectors and transimpedance amplifiers
Li, Shuxia; Tarr, N. Garry; Ye, Winnie N.
2018-02-01
In the absence of commercial foundry technologies offering silicon-on-insulator (SOI) photonics combined with Complementary Metal Oxide Semiconductor (CMOS) transistors, monolithic integration of conventional electronics with SOI photonics is difficult. Here we explore the implementation of lateral bipolar junction transistors (LBJTs) and Junction Field Effect Transistors (JFETs) in a commercial SOI photonics technology lacking MOS devices but offering a variety of n- and p-type ion implants intended to provide waveguide modulators and photodetectors. The fabrication makes use of the commercial Institute of Microelectronics (IME) SOI photonics technology. Based on knowledge of device doping and geometry, simple compact LBJT and JFET device models are developed. These models are then used to design basic transimpedance amplifiers integrated with optical waveguides. The devices' experimental current-voltage characteristics results are reported.
International Nuclear Information System (INIS)
Li Ou-Peng; Zhang Yong; Xu Rui-Min; Cheng Wei; Wang Yuan; Niu Bing; Lu Hai-Yan
2016-01-01
Design and characterization of a G-band (140–220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140–190 GHz respectively. The saturation output powers are −2.688 dBm at 210 GHz and −2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. (paper)
Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Matsumoto, Atsushi; Kawanishi, Tetsuya
2016-04-01
A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed with T-band (1.0 µm waveband) and O-band (1.3 µm waveband) QD optical gain materials for Gbps-order, high-speed optical data generation. The insertion loss due to coupling between the device and the optical fiber was effectively compensated for by the SOA section. It was also confirmed that the monolithic QD-OGM/SOA device enabled >4.8 Gbps optical data generation with a clear eye opening in the T-band. Furthermore, we successfully demonstrated error-free 4.8 Gbps optical data transmissions in each of the six wavelength channels over a 10-km-long photonic crystal fiber using the monolithic QD-OGM/SOA device in multiple O-band wavelength channels, which were generated by the single QD gain chip. These results suggest that the monolithic QD-OGM/SOA device will be advantageous in ultra-broadband optical frequency systems that utilize the T+O-band for short- and medium-range optical communications.
International Nuclear Information System (INIS)
Varner, R.L.; Blankenship, J.L.; Beene, J.R.; Todd, R.A.
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 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 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
Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya
2015-04-01
A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed. Broadband QD optical gain material was used to achieve Gbps-order high-speed optical data transmission, and an optical gain change as high as approximately 6-7 dB was obtained with a low OGM voltage of 2.0 V. Loss of optical power due to insertion of the device was also effectively compensated for by the SOA section. Furthermore, it was confirmed that the QD-OGM/SOA device helped achieve 6.0-Gbps error-free optical data transmission over a 2.0-km-long photonic crystal fiber. We also successfully demonstrated generation of Gbps-order, high-speed, and error-free optical signals in the >5.5-THz broadband optical frequency bandwidth larger than the C-band. These results suggest that the developed monolithically integrated QD-OGM/SOA device will be an advantageous and compact means of increasing the usable optical frequency channels for short-reach communications.
Simulating characteristics of Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer
Directory of Open Access Journals (Sweden)
Gnilenko A. B.
2015-12-01
Full Text Available In spite of many efforts to propose new semiconductor materials and sophisticated constructions of solar cells, crystalline silicone remains the main photovoltaic material widely used up to now. There are various methods to enhance the efficiency of silicone solar cells. One of them is to combine silicone with an additional semiconductor material with the different bandgap to form a tandem construction. For example, the germanium sub-cell used as the bottom cascade for the silicone sub-cell in the tandem monolithic solar cell makes it possible to utilize the "red" sub-band of solar spectra increasing overall solar cell efficiency. The problem of the 4.2% mismatch in lattice constant between Si and Ge can be resolved in such a case by the use of SiGe buffer layer. In the paper the results of the computer simulation for Si/Ge tandem monolithic solar cell with Si1-xGex buffer layer are presented. In the solar cell under consideration, the step graded Si1-xGex buffer layer is located between the top silicone and the bottom germanium cascades to reduce the threading dislocation density in mismatched materials. The cascades are commutated by the use of the germanium tunnel diode between the bottom sub-cell and the buffer layer. For the solar cell modeling, the physically-based device simulator ATLAS of Silvaco TCAD software is employed to predict the electrical behavior of the semiconductor structure and to provide a deep insight into the internal physical processes. The voltage-current characteristic, photovoltaic parameters and the distribution of basic physical values are obtained for the investigated tandem solar cell. The influence of layer thicknesses on the photovoltaic parameters is studied. The calculated efficiency of the tandem solar cell reaches 13% which is a quarter more than the efficiency of a simple silicone solar cell with the same constructive parameters and under the same illumination conditions.
Aspartic acid incorporated monolithic columns for affinity glycoprotein purification.
Armutcu, Canan; Bereli, Nilay; Bayram, Engin; Uzun, Lokman; Say, Rıdvan; Denizli, Adil
2014-02-01
Novel aspartic acid incorporated monolithic columns were prepared to efficiently affinity purify immunoglobulin G (IgG) from human plasma. The monolithic columns were synthesised in a stainless steel HPLC column (20 cm × 5 mm id) by in situ bulk polymerisation of N-methacryloyl-L-aspartic acid (MAAsp), a polymerisable derivative of L-aspartic acid, and 2-hydroxyethyl methacrylate (HEMA). Monolithic columns [poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-aspartic acid) (PHEMAsp)] were characterised by swelling studies, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The monolithic columns were used for IgG adsorption/desorption from aqueous solutions and human plasma. The IgG adsorption depended on the buffer type, and the maximum IgG adsorption from aqueous solution in phosphate buffer was 0.085 mg/g at pH 6.0. The monolithic columns allowed for one-step IgG purification with a negligible capacity decrease after ten adsorption-desorption cycles. Copyright © 2013 Elsevier B.V. All rights reserved.
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.
Ongkudon, Clarence M; Danquah, Michael K
2010-10-15
Anion exchange monolithic chromatography is increasingly becoming a prominent tool for plasmid DNA purification but no generic protocol is available to purify all types of plasmid DNA. In this work, we established a simple framework and used it to specifically purify a plasmid DNA model from a clarified alkaline-lysed plasmid-containing cell lysate. The framework involved optimising ligand functionalisation temperature (30-80°C), mobile phase flow rate (0.1-1.8mL/min), monolith pore size (done by changing the porogen content in the polymerisation reaction by 50-80%), buffer pH (6-10), ionic strength of binding buffer (0.3-0.7M) and buffer gradient elution slope (1-10% buffer B/min). We concluded that preferential pcDNA3F adsorption and optimum resolution could be achieved within the tested conditions by loading the clarified cell lysate into 400nm pore size of monolith in 0.7M NaCl (pH 6) of binding buffer followed by increasing the NaCl concentration to 1.0M at 3%B/min. Copyright © 2010 Elsevier B.V. All rights reserved.
Stability investigation for InP DHBT mm‐wave power amplifier
DEFF Research Database (Denmark)
Yan, Lei; Johansen, Tom Keinicke; Kammersgaard, Jacob
2013-01-01
microwave integrated circuit power amplifier. Experimental results from a redesigned power amplifier with improved stability are presented to confirm that the previously detected oscillation loop is removed using odd‐mode stabilization resistors with the correct choice of values and locations. © 2012 Wiley......In this article, we discuss stability issues for mm‐wave monolithic integrated power amplifiers using InP double heterojunction bipolar transistor (DHBT) technology targeting E‐band applications at 71–76 GHz and 81–86 GHz. Different stability detection methods based on the classical two‐port K......‐Δs pair, linear three‐port graphical analysis, system identifications, circuit modal analysis, and normalized determinant function are all reviewed. The corresponding techniques are employed to predict the occurrence of instability at 15 GHz observed during measurements on a fabricated monolithic...
InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz
Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, William; Dang, Linh; Li, Danny; Cavus, Abdullah; To, Richard; Lai, Richard
2009-01-01
Two single-stage InP heterojunction bipolar transistor (HBT) amplifiers operate at 184 and 255 GHz, using Northrop Grumman Corporation s InP HBT MMIC (monolithic microwave integrated circuit) technology. At the time of this reporting, these are reported to be the highest HBT amplifiers ever created. The purpose of the amplifier design is to evaluate the technology capability for high-frequency designs and verify the model for future development work.
International Nuclear Information System (INIS)
Zhang, Andy Zhenzhong; Wang, Qin; Fonjallaz, Pierre-Yves; Almqvist, Susanne; Karlsson, Stefan; Kjebon, Olle; Schatz, Richard; Chacinski, Marek; Thylén, Lars; Berggren, Jesper; Hammar, Mattias; Honecker, Jörg; Steffan, Andreas
2011-01-01
We report on the fabrication of a monolithically integrated semiconductor optical amplifier (SOA) and a reflective electro-absorption transceiver (EAT) for 40–60 GHz radio-over-fiber applications. The EAT can either function as a transmitter (reflective modulator) or as a receiver (photodetector) depending on operation mode. The SOA and the EAT sections are based on different InGaAsP multiple quantum-well active layers connected by a butt joint. Benzocyclobutene is used to reduce the capacitance beside the ridge mesa. Devices are designed to have a peaked response at the operating frequency through the design of microwave waveguides on top of the devices. The packaged device exhibits at 0.1 mW optical input power an amplified DC responsivity of 18.5 mA mW −1 and a modulation efficiency of 0.67 mW V −1 . The estimated radio frequency loss at 40 GHz of an optical link consisting of two SOA–EAT devices was 23 dB using an unmodulated optical input carrier to the transmitter of 0.94 mW
Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya
2015-03-01
Short-range interconnection and/or data center networks require high capacity and a large number of channels in order to support numerous connections. Solutions employed to meet these requirements involve the use of alternative wavebands to increase the usable optical frequency range. We recently proposed the use of the T- and O-bands (Thousand band: 1000-1260 nm, Original band: 1260-1360 nm) as alternative wavebands because large optical frequency resources (>60 THz) can be easily employed. In addition, a simple and compact Gb/s-order high-speed optical modulator is a critical photonic device for short-range communications. Therefore, to develop an optical modulator that acts as a highfunctional photonic device, we focused on the use of self-assembled quantum dots (QDs) as a three-dimensional (3D) confined structure because QD structures are highly suitable for realizing broadband optical gain media in the T+O bands. In this study, we use the high-quality broadband QD optical gain to develop a monolithically integrated QD optical gain modulator (QD-OGM) device that has a semiconductor optical amplifier (QD-SOA) for Gb/s-order highspeed optical data generation in the 1.3-μm waveband. The insertion loss of the device can be compensated through the SOA, and we obtained an optical gain change of up to ~7 dB in the OGM section. Further, we successfully demonstrate a 10-Gb/s clear eye opening using the QD-OGM/SOA device with a clock-data recovery sequence at the receiver end. These results suggest that the monolithic QD-EOM/SOA is suitable for increasing the number of wavelength channels for smart short-range communications.
Three-Stage InP Submillimeter-Wave MMIC Amplifier
Pukala, David; Samoska, Lorene; Man, King; Gaier, Todd; Deal, William; Lai, Richard; Mei, Gerry; Makishi, Stella
2008-01-01
A submillimeter-wave monolithic integrated- circuit (S-MMIC) amplifier has been designed and fabricated using an indium phosphide (InP) 35-nm gate-length high electron mobility transistor (HEMT) device, developed at Northrop Grumman Corporation. The HEMT device employs two fingers each 15 micrometers wide. The HEMT wafers are grown by molecular beam epitaxy (MBE) and make use of a pseudomorphic In0.75Ga0.25As channel, a silicon delta-doping layer as the electron supply, an In0.52Al0.48As buffer layer, and an InP substrate. The three-stage design uses coplanar waveguide topology with a very narrow ground-to-ground spacing of 14 micrometers. Quarter-wave matching transmission lines, on-chip metal-insulator-metal shunt capacitors, series thin-film resistors, and matching stubs were used in the design. Series resistors in the shunt branch arm provide the basic circuit stabilization. The S-MMIC amplifier was measured for S-parameters and found to be centered at 320 GHz with 13-15-dB gain from 300-345 GHz. This chip was developed as part of the DARPA Submillimeter Wave Imaging Focal Plane Technology (SWIFT) program (see figure). Submillimeter-wave amplifiers could enable more sensitive receivers for earth science, planetary remote sensing, and astrophysics telescopes, particularly in radio astronomy, both from the ground and in space. A small atmospheric window at 340 GHz exists and could enable ground-based observations. However, the submillimeter-wave regime (above 300 GHz) is best used for space telescopes as Earth s atmosphere attenuates most of the signal through water and oxygen absorption. Future radio telescopes could make use of S-MMIC amplifiers for wideband, low noise, instantaneous frequency coverage, particularly in the case of heterodyne array receivers.
Characterization of SOI monolithic detector system
Álvarez-Rengifo, P. L.; Soung Yee, L.; Martin, E.; Cortina, E.; Ferrer, C.
2013-12-01
A monolithic active pixel sensor for charged particle tracking was developed. This research is performed within the framework of an R&D project called TRAPPISTe (Tracking Particles for Physics Instrumentation in SOI Technology) whose aim is to evaluate the feasibility of developing a Monolithic Active Pixel Sensor (MAPS) with Silicon-on-Insulator (SOI) technology. Two chips were fabricated: TRAPPISTe-1 and TRAPPISTe-2. TRAPPISTe-1 was produced at the WINFAB facility at the Université catholique de Louvain (UCL), Belgium, in a 2 μm fully depleted (FD-SOI) CMOS process. TRAPPISTe-2 was fabricated with the LAPIS 0.2 μm FD-SOI CMOS process. The electrical characterization on single transistor test structures and of the electronic readout for the TRAPPISTe series of monolithic pixel detectors was carried out. The behavior of the prototypes’ electronics as a function of the back voltage was studied. Results showed that both readout circuits exhibited sensitivity to the back voltage. Despite this unwanted secondary effect, the responses of TRAPPISTe-2 amplifiers can be improved by a variation in the circuit parameters.
International Nuclear Information System (INIS)
Haralabidis, N.; Loukas, D.; Misiakos, K.; Katsafouros, S.
1997-01-01
A fast transimpedance multichannel amplifier has been designed, fabricated in CMOS 1.2-microm technology and tested. Each channel consists of a current sensitive preamplifier followed by a voltage amplification stage and an on-chip buffer able to drive 50 Ω loads with an output range of ±800 mV. Measured peaking time at the output is 40 ns and the circuit recovers to baseline in 90 ns. This results in a counting capability of more than 10 7 hits/s. Signals of both polarities can be handled. The first two stages consume a total of 2 mW per channel and the 50 Ω buffer consumes another 17 mW. The equivalent noise charge (ENC) is 1,100 e - rms with a slope of 40e - /pF. The IC is intended for use in gas and solid-state detectors with high particle rate and extensive charge release as in high energy calorimetry
Remote Acquisition Amplifier For 50-Ohm Cable
Amador, Jose J.
1995-01-01
Buffer-amplifier unit designed to drive 50-Ohm cables up to 100 ft. (30 m) long, compensating for attenuation in cables and enabling remote operation of oscilloscopes. Variable resistor provides for adjustment of gain of amplifier, such that overall gain from input terminals of amplifier to output end of cable set to unity.
W-band InP based HEMT MMIC low noise amplifiers
Lin, K. Y.; Tang, Y. L.; Wang, H.; Gaier, T.; Gough, R. G.; Sinclair, M.
2002-01-01
This paper presents the designs and measurement results of a three-stage and a four-stage W-band monolithic microwave integrated circuits (MMIC) including a three-stage and a four-stage low noise amplifiers.
International Nuclear Information System (INIS)
Takano, H.; Hosogi, K.; Kato, T.
1995-01-01
A fully ion-implanted self-aligned T-shaped gate Ga As metal-semiconductor field-effect transistor (MESFET) with high frequency and extremely low-noise performance has been successfully fabricated for super low-noise microwave monolithic integrated circuit (MMIC) amplifiers. A subhalf-micrometer gate structure composed of WSi/Ti/Mo/Au is employed to reduce gate resistance effectively. This multilayer gate structure is formed by newly developed dummy SiON self-alignment technology and a photoresist planarization process. At an operating frequency of 12 GHz, a minimum noise figure of 0.87 dB with an associated gain of 10.62 dB has been obtained. Based on the novel FET process, a low-noise single-stage MMIC amplifier with an excellent low-noise figure of 1.2 dB with an associated gain of 8 dB in the 14 GHz band has been realized. This is the lowest noise figure ever reported at this frequency for low-noise MMICs based on ion-implanted self-aligned gate MESFET technology. 14 refs., 9 figs
Optically pumped alkali laser and amplifier using helium-3 buffer gas
Beach, Raymond J.; Page, Ralph; Soules, Thomas; Stappaerts, Eddy; Wu, Sheldon Shao Quan
2010-09-28
In one embodiment, a laser oscillator is provided comprising an optical cavity, the optical cavity including a gain medium including an alkali vapor and a buffer gas, the buffer gas including .sup.3He gas, wherein if .sup.4He gas is also present in the buffer gas, the ratio of the concentration of the .sup.3He gas to the .sup.4He gas is greater than 1.37.times.10.sup.-6. Additionally, an optical excitation source is provided. Furthermore, the laser oscillator is capable of outputting radiation at a first frequency. In another embodiment, an apparatus is provided comprising a gain medium including an alkali vapor and a buffer gas including .sup.3He gas, wherein if .sup.4He gas is also present in the buffer gas, the ratio of the concentration of the .sup.3He gas to the .sup.4He gas is greater than 1.37.times.10.sup.-6. Other embodiments are also disclosed.
Soung Yee, L.; Alvarez, P.; Martin, E.; Cortina, E.; Ferrer, C.
2012-12-01
A monolithic active pixel sensor for charged particle tracking has been developed within the frame of a research and development project called TRAPPISTe (Tracking Particles for Physics Instrumentation in SOI Technology). TRAPPISTe aims to study the feasibility of developing a monolithic pixel sensor with SOI technology. TRAPPISTe-2 is the second prototype in this series and was fabricated with an OKI 0.20μm fully depleted (FD-SOI) CMOS process. This device contains test transistors and amplifiers, as well as two pixel matrices with integrated 3-transistor and amplifier readout electronics. The results presented are based on the first electrical measurements performed on the test structures and laser measurements on the pixel matrices.
Design procedure for millimeter-wave InP DHBT stacked power amplifiers
DEFF Research Database (Denmark)
Squartecchia, Michele; Johansen, Tom Keinicke; Midili, Virginio
2015-01-01
The stacked-transistor concept for power amplifiers (PA) has been investigated in this work. Specifically, this architecture has been applied in the design of millimeter-wave monolithic microwave integrated circuits (MMICs) using indium phosphide (InP) double heterojunction bipolar transistors...
Test of the TRAPPISTe monolithic detector system
Soung Yee, L.; Álvarez, P.; Martin, E.; Cortina, E.; Ferrer, C.
2013-12-01
A monolithic pixel detector named TRAPPISTe-2 has been developed in Silicon-on-Insulator (SOI) technology. A p-n junction is implanted in the bottom handle wafer and connected to readout electronics integrated in the top active layer. The two parts are insulated from each other by a buried oxide layer resulting in a monolithic detector. Two small pixel matrices have been fabricated: one containing a 3-transistor readout and a second containing a charge sensitive amplifier readout. These two readout structures have been characterized and the pixel matrices were tested with an infrared laser source. The readout circuits are adversely affected by the backgate effect, which limits the voltage that can be applied to the metal back plane to deplete the sensor, thus narrowing the depletion width of the sensor. Despite the low depletion voltages, the integrated pixel matrices were able to respond to and track a laser source.
DEFF Research Database (Denmark)
Jain, Saurabh; Castro, Carlos; Jung, Yongmin
2017-01-01
We present a high-core-count 32-core multicore erbium/ytterbium-doped fiber amplifier (32c-MC-EYDFA) in a cladding pumped configuration. A side pumping technique is employed for ease of pump coupling in this monolithic all-fiber amplifier. A minimum gain of >17 dB and an average noise figure (NF)...
Development of Buffer Layer Technologies for LWIR and VLWIR HgCdTe Integration on Si
National Research Council Canada - National Science Library
Golding, Terry D
2005-01-01
This program proposed to develop manufacturable, cost-effective buffer layer technologies that would allow either hybrid or monolithic integration of LWIR and VLWIR HgCdTe infrared focal plane arrays...
A monolithically integrated detector-preamplifier on high-resistivity silicon
International Nuclear Information System (INIS)
Holland, S.; Spieler, H.
1990-02-01
A monolithically integrated detector-preamplifier on high-resistivity silicon has been designed, fabricated and characterized. The detector is a fully depleted p-i-n diode and the preamplifier is implemented in a depletion-mode PMOS process which is compatible with detector processing. The amplifier is internally compensated and the measured gain-bandwidth product is 30 MHz with an input-referred noise of 15 nV/√Hz in the white noise regime. Measurements with an Am 241 radiation source yield an equivalent input noise charge of 800 electrons at 200 ns shaping time for a 1.4 mm 2 detector with on-chip amplifier in an experimental setup with substantial external pickup
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.
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)
A 1.5 Gb/s monolithically integrated optical receiver in the standard CMOS process
Energy Technology Data Exchange (ETDEWEB)
Xiao Xindong; Mao Luhong; Yu Changliang; Zhang Shilin; Xie Sheng, E-mail: xxd@tju.edu.c [School of Electronic Information Engineering, Tianjin University, Tianjin 300072 (China)
2009-12-15
A monolithically integrated optical receiver, including the photodetector, has been realized in Chartered 0.35 {mu}m EEPROM CMOS technology for 850 nm optical communication. The optical receiver consists of a differential photodetector, a differential transimpedance amplifier, three limiting amplifiers and an output circuit. The experiment results show that the receiver achieves an 875 MHz 3 dB bandwidth, and a data rate of 1.5 Gb/s is achieved at a bit-error-rate of 10{sup -9}. The chip dissipates 60 mW under a single 3.3 V supply. (semiconductor integrated circuits)
A 1.5 Gb/s monolithically integrated optical receiver in the standard CMOS process
International Nuclear Information System (INIS)
Xiao Xindong; Mao Luhong; Yu Changliang; Zhang Shilin; Xie Sheng
2009-01-01
A monolithically integrated optical receiver, including the photodetector, has been realized in Chartered 0.35 μm EEPROM CMOS technology for 850 nm optical communication. The optical receiver consists of a differential photodetector, a differential transimpedance amplifier, three limiting amplifiers and an output circuit. The experiment results show that the receiver achieves an 875 MHz 3 dB bandwidth, and a data rate of 1.5 Gb/s is achieved at a bit-error-rate of 10 -9 . The chip dissipates 60 mW under a single 3.3 V supply. (semiconductor integrated circuits)
Determination of over current protection thresholds for class D audio amplifiers
DEFF Research Database (Denmark)
Nyboe, Flemming; Risbo, L; Andreani, Pietro
2005-01-01
Monolithic class-D audio amplifiers typically feature built-in over current protection circuitry that shuts down the amplifier in case of a short circuit on the output speaker terminals. To minimize cost, the threshold at which the device shuts down must be set just above the maximum current...... that can flow in the loudspeaker during normal operation. The current required is determined by the complex loudspeaker impedance and properties of the music signals played. This work presents a statistical analysis of peak output currents when playing music on typical loudspeakers for home entertainment....
Rubin, Mark; Stuart, Rebecca
2018-01-01
The present research investigated different types of social class identification as moderators of the negative relation between social class and mental health problems. Psychology undergraduates (N = 355) completed an online survey that included measures of social class, mental health and well-being, and three aspects of social class identification: importance of identity, salience of identity, and perceived self-class similarity. Perceived self-class similarity buffered the negative association between social class and depressive symptoms. However, importance and salience of social class identity amplified the associations between social class and anxiety and life satisfaction. These findings contribute to a more sophisticated understanding of the way in which social identification may operate as a social cure.
Ott, Sonja; Niessner, Reinhard; Seidel, Michael
2011-08-01
Macroporous epoxy-based monolithic columns were used for immunofiltration of bacteria. The prepared monolithic polymer support is hydrophilic and has large pore sizes of 21 μm without mesopores. A surface chemistry usually applied for immobilization of antibodies on glass slides is successfully transferred to monolithic columns. Step-by-step, the surface of the epoxy-based monolith is hydrolyzed, silanized, coated with poly(ethylene glycol diamine) and activated with the homobifunctional crosslinker di(N-succinimidyl)carbonate for immobilization of antibodies on the monolithic columns. The functionalization steps are characterized to ensure the coating of each monolayer. The prepared antibody-immobilized monolithic column is optimized for immunofiltration to enrich Staphylococcus aureus as an important food contaminant. Different kinds of geometries of monolithic columns, flow rates and elution buffers are tested with the goal to get high recoveries in the shortest enrichment time as possible. An effective capture of S. aureus was achieved at a flow rate of 7.0 mL/min with low backpressures of 20.1±5.4 mbar enabling a volumetric enrichment of 1000 within 145 min. The bacteria were quantified by flow cytometry using a double-labeling approach. After immunofiltration the sensitivity was significantly increased and a detection limit of the total system of 42 S. aureus/mL was reached. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
High gain semiconductor optical amplifier — Laser diode at visible wavelength
Shen, Chao; Lee, Changmin; Ng, Tien Khee; Nakamura, Shuji; Speck, James S.; DenBaars, Steven P.; Alyamani, Ahmed Y.; El-Desouki, Munir M.; Ooi, Boon S.
2017-01-01
We reported on the first experimental demonstration of a two-section semipolar InGaN-based laser diode with monolithically integrated semiconductor optical amplifier (SOA-LD). The onset of amplification effect was measured at 4V SOA bias (VSOA). The SOA-LD shows a large gain of 5.32 dB at Vsoa = 6 V.
High gain semiconductor optical amplifier — Laser diode at visible wavelength
Shen, Chao
2017-02-07
We reported on the first experimental demonstration of a two-section semipolar InGaN-based laser diode with monolithically integrated semiconductor optical amplifier (SOA-LD). The onset of amplification effect was measured at 4V SOA bias (VSOA). The SOA-LD shows a large gain of 5.32 dB at Vsoa = 6 V.
Demodulation Radio Frequency Interference Effects in Operational Amplifier Circuits
Sutu, Yue-Hong
A series of investigations have been carried out to determine RFI effects in analog circuits using monolithic integrated operational amplifiers (op amps) as active devices. The specific RFI effect investigated is how amplitude-modulated (AM) RF signals are demodulated in op amp circuits to produce undesired low frequency responses at AM-modulation frequency. The undesired demodulation responses were shown to be characterized by a second-order nonlinear transfer function. Four representative op amp types investigated were the 741 bipolar op amp, the LM10 bipolar op amp, the LF355 JFET-Bipolar op amp, and the CA081 MOS-Bipolar op amp. Two op amp circuits were investigated. The first circuit was a noninverting unity voltage gain buffer circuit. The second circuit was an inverting op amp configuration. In the second circuit, the investigation includes the effects of an RFI suppression capacitor in the feedback path. Approximately 30 units of each op amp type were tested to determine the statistical variations of RFI demodulation effects in the two op amp circuits. The Nonlinear Circuit Analysis Program, NCAP, was used to simulate the demodulation RFI response. In the simulation, the op amp was replaced with its incremental macromodel. Values of macromodel parameters were obtained from previous investigations and manufacturer's data sheets. Some key results of this work are: (1) The RFI demodulation effects are 10 to 20 dB lower in CA081 and LF355 FET-bipolar op amp than in 741 and LM10 bipolar op amp except above 40 MHz where the LM10 RFI response begins to approach that of CA081. (2) The experimental mean values for 30 741 op amps show that RFI demodulation responses in the inverting amplifier with a 27 pF feedback capacitor were suppressed from 10 to 35 dB over the RF frequency range 0.1 to 150 MHz except at 0.15 MHz where only 3.5 dB suppression was observed. (3) The NCAP program can predict RFI demodulation responses in 741 and LF355 unity gain buffer circuits
Optical Sensitivity of a Monolithic Integrated InP PIN-HEMT-HBT Transimpedance Amplifier
Matiss, A.; Janssen, G.; Bertenburg, R. M.; Brockerhoff, W.; Tegude, F.J.
2004-01-01
To improve sensitivity of optical receivers, a special integration concept is chosen that includes a pinphotodiode, high-electron mobility transistors (HEMT) and heterostructure bipolar transistors (HBT) on a single substrate. This work focuses on the optimization of the amplifier design to achieve lowest input noise currents of a transimpedance amplifier, and thus highest receiver sensitivity. The respective advantages of the components used are investigated with respect...
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.
A 240W Monolithic Class-D Audio Amplifier Output Stage
DEFF Research Database (Denmark)
Nyboe, Flemming; Kaya, Cetin; Risbo, Lars
2006-01-01
A single-channel class-D audio amplifier output stage outputs 240W undipped into 4Omega 0.1% open-loop THD+N allows using the device in a fully-digital audio signal path with no feedback. The output current capability is plusmn18A and the part is fabricated in a 0.4mum/1.8mum high-voltage Bi...
DEFF Research Database (Denmark)
Fischer, St.; Dülk, M.; Gamper, E.
2000-01-01
We present a novel method for all-optical add-drop multiplexing having regenerative capability for 40-Gb/s optical time-division multiplexed (OTDM) data using a semiconductor optical amplifier (SOA) based, monolithic Mach-Zehnder interferometer (MZI). Simultaneous dropping of one 10-Gb/s channel ...
Muñoz, P.; García-Olcina, R.; Doménech, J.D.; Rius, M.; Capmany, J.; Chen, L.R.; Habib, C.; Leijtens, X.J.M.; Vries, de T.; Heck, M.J.R.; Augustin, L.M.; Nötzel, R.; Robbins, D.J.
2010-01-01
In this paper, a multi-wavelength laser monolithically integrated on InP is presented. A linear laser cavity is built between two integrated Sagnac loop reflectors, with an Arrayed Waveguide Grating (AWG) as frequency selective device, and Semiconductor Optical Amplifiers (SOA) as gain sections. The
Wideband pulse amplifiers for the NECTAr chip
International Nuclear Information System (INIS)
Sanuy, A.; Delagnes, E.; Gascon, D.; Sieiro, X.; Bolmont, J.; Corona, P.; Feinstein, F.; Glicenstein, J-F.; Naumann, C.L.; Nayman, P.; Ribó, M.
2012-01-01
The NECTAr collaboration's FE option for the camera of the CTA is a 16 bits and 1–3 GS/s sampling chip based on analog memories including most of the readout functions. This works describes the input amplifiers of the NECTAr ASIC. A fully differential wideband amplifier, with voltage gain up to 20 V/V and a BW of 400 MHz. As it is impossible to design a fully differential OpAmp with an 8 GHz GBW product in a 0.35 CMOS technology, an alternative implementation based on HF linearized transconductors is explored. The output buffer is a class AB miller operational amplifier, with special non-linear current boost.
Wideband pulse amplifiers for the NECTAr chip
Sanuy, A.; Delagnes, E.; Gascon, D.; Sieiro, X.; Bolmont, J.; Corona, P.; Feinstein, F.; Glicenstein, J.-F.; Naumann, C. L.; Nayman, P.; Ribó, M.; Tavernet, J.-P.; Toussenel, F.; Vincent, P.; Vorobiov, S.
2012-12-01
The NECTAr collaboration's FE option for the camera of the CTA is a 16 bits and 1-3 GS/s sampling chip based on analog memories including most of the readout functions. This works describes the input amplifiers of the NECTAr ASIC. A fully differential wideband amplifier, with voltage gain up to 20 V/V and a BW of 400 MHz. As it is impossible to design a fully differential OpAmp with an 8 GHz GBW product in a 0.35 CMOS technology, an alternative implementation based on HF linearized transconductors is explored. The output buffer is a class AB miller operational amplifier, with special non-linear current boost.
A 240W Monolithic Class-D Audio Amplifier Output Stage
Nyboe, Flemming; Kaya, Cetin; Risbo, Lars; Andreani, Pietro
2006-01-01
A single-channel class-D audio amplifier output stage outputs 240W undipped into 4Omega 0.1% open-loop THD+N allows using the device in a fully-digital audio signal path with no feedback. The output current capability is plusmn18A and the part is fabricated in a 0.4mum/1.8mum high-voltage BiCMOS process. Over-current sensing protects the output from short circuits.
Microwave monolithic integrated circuit development for future spaceborne phased array antennas
Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.
1984-01-01
The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399
Microwave monolithic integrated circuit development for future spaceborne phased array antennas
Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.
The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399
Wideband pulse amplifiers for the NECTAr chip
Energy Technology Data Exchange (ETDEWEB)
Sanuy, A., E-mail: asanuy@ecm.ub.es [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Delagnes, E. [IRFU/DSM/CEA, CE-Saclay, Bat. 141 SEN Saclay, F-91191, Gif-sur-Yvette (France); Gascon, D. [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Sieiro, X. [Departament d' Electronica, Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Barre 12-22, 1er etage, 4 place Jussieu, 75252 Paris (France); Feinstein, F. [LUPM, Universite Montpellier II and IN2P3/CNRS, CC072, bat. 13, place Eugene Bataillon, 34095 Montpellier (France); Glicenstein, J-F. [IRFU/DSM/CEA, CE-Saclay, Bat. 141 SEN Saclay, F-91191, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Barre 12-22, 1er etage, 4 place Jussieu, 75252 Paris (France); Ribo, M. [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); and others
2012-12-11
The NECTAr collaboration's FE option for the camera of the CTA is a 16 bits and 1-3 GS/s sampling chip based on analog memories including most of the readout functions. This works describes the input amplifiers of the NECTAr ASIC. A fully differential wideband amplifier, with voltage gain up to 20 V/V and a BW of 400 MHz. As it is impossible to design a fully differential OpAmp with an 8 GHz GBW product in a 0.35 CMOS technology, an alternative implementation based on HF linearized transconductors is explored. The output buffer is a class AB miller operational amplifier, with special non-linear current boost.
Nishi, Hidetaka; Tsuchizawa, Tai; Kou, Rai; Shinojima, Hiroyuki; Yamada, Takashi; Kimura, Hideaki; Ishikawa, Yasuhiko; Wada, Kazumi; Yamada, Koji
2012-04-09
On the silicon (Si) photonic platform, we monolithically integrated a silica-based arrayed-waveguide grating (AWG) and germanium (Ge) photodiodes (PDs) using low-temperature fabrication technology. We confirmed demultiplexing by the AWG, optical-electrical signal conversion by Ge PDs, and high-speed signal detection at all channels. In addition, we mounted a multichannel transimpedance amplifier/limiting amplifier (TIA/LA) circuit on the fabricated AWG-PD device using flip-chip bonding technology. The results show the promising potential of our Si photonic platform as a photonics-electronics convergence.
International Nuclear Information System (INIS)
Kumar, V Vinoth; Dasgupta, A; Bhat, K N; KNatarajan
2006-01-01
In this paper we present the design and process optimization for fabricating piezoresitive pressure sensor and MOSFET Differential Amplifier simultaneously on the same chip. Silicon On Insulator approach has been used for realizing the membrane as well as the electronics on the same chip. The amplifier circuit has been configured in the common source connection and it has been designed with PSPICE simulation to achieve a voltage gain of about 5. In the initial set of experiments the Pressure sensor and the amplifier were fabricated on separate chips to optimize the process steps and tested in the hybrid mode. In the next set of experiments, SOI wafer having the SOI layer thickness of about 11 microns was used for realizing the membrane by anisotropic etching from the backside. The piezo-resistive pressure sensor was realized on this membrane by connecting the polysilicon resistors in the form of a Wheatstone bridge. The MOSFET source follower amplifier was also fabricated on the same SOI wafer by tailoring the process steps to suit the requirement of simultaneous fabrication of piezoresistors and the amplifier for achieving MOSFET Integrated Pressure Sensor. Reproducible results have been achieved on the SOI wafers, with the process steps developed in the laboratory. Sensitivity of 270 mV /Bar/10V, with the on chip amplifier gain of 4.5, has been achieved with this process
Reprogrammable read only variable threshold transistor memory with isolated addressing buffer
Lodi, Robert J.
1976-01-01
A monolithic integrated circuit, fully decoded memory comprises a rectangular array of variable threshold field effect transistors organized into a plurality of multi-bit words. Binary address inputs to the memory are decoded by a field effect transistor decoder into a plurality of word selection lines each of which activates an address buffer circuit. Each address buffer circuit, in turn, drives a word line of the memory array. In accordance with the word line selected by the decoder the activated buffer circuit directs reading or writing voltages to the transistors comprising the memory words. All of the buffer circuits additionally are connected to a common terminal for clearing all of the memory transistors to a predetermined state by the application to the common terminal of a large magnitude voltage of a predetermined polarity. The address decoder, the buffer and the memory array, as well as control and input/output control and buffer field effect transistor circuits, are fabricated on a common substrate with means provided to isolate the substrate of the address buffer transistors from the remainder of the substrate so that the bulk clearing function of simultaneously placing all of the memory transistors into a predetermined state can be performed.
DEFF Research Database (Denmark)
Champagne, A.; Lestrade, Michel; Camel, Jérôme
2004-01-01
The degradation of the side-mode suppression ratio (SMSR) in a monolithically integrated distributed feedback laser and semiconductor optical amplifier (SOA) cavity is investigated. An expression is derived that gives the degradation of the SMSR in the case of a perfectly antireflection-coated SO...
Directory of Open Access Journals (Sweden)
Chalore Teepakorn
2016-09-01
Full Text Available These last few decades, membranes and monoliths have been increasingly used as stationary phases for chromatography. Their fast mass transfer is mainly based on convection, which leads to reduced diffusion, which is usually observed in resins. Nevertheless, poor flow distribution, which causes inefficient binding, remains a major challenge for the development of both membrane and monolith devices. Moreover, the comparison of membranes and monoliths for biomolecule separation has been very poorly investigated. In this paper, the separation of two proteins, bovine serum albumin (BSA and lactoferrin (LF, with similar sizes, but different isoelectric points, was investigated at a pH of 6.0 with a BSA-LF concentration ratio of 2/1 (2.00 mg·mL−1 BSA and 1.00 mg·mL−1 LF solution using strong cation exchange membranes and monoliths packed in the same housing, as well as commercialized devices. The feeding flow rate was operated at 12.0 bed volume (BV/min for all devices. Afterward, bound LF was eluted using a phosphate-buffered saline solution with 2.00 M NaCl. Using membranes in a CIM housing from BIA Separations (Slovenia with porous frits before and after the membrane bed, higher binding capacities, sharper breakthrough curves, as well as sharper and more symmetric elution peaks were obtained. The monolith and commercialized membrane devices showed lower LF binding capacity and broadened and non-symmetric elution peaks.
A monolithic charge multiplexer with 0.5% accuracy
International Nuclear Information System (INIS)
Lewis, J.; McPherson, G.M.; Morrissey, M.C.; Thompson, J.C.; Tucker, A.W.
1990-01-01
This paper describes a 16 channel monolithic charge multiplexer providing a close tolerance, low cost, low power solution to the problem of handling the signals from detectors with large numbers of channels. Outputs may be wire-orred to increase the degree of multiplexing. A system designed with this chip and with suitable close tolerance processing downstream will have a gain match of ±0.5% and a front end chip cost of approximately $1 per channel. The chip is fabricated in CMOS technology and the test of a 1500 channel system has demonstrated the feasibility of CMOS in this context. The chip produces a prompt sum of the charges from the 16 signal sources and integrates and stores the individual charges for later serial readout. A single network provides amplifier bias and releases area to facilitate optimum noise performance and signal handling. Amplifier and bias network design together with p-well screens to isolate storage capacitors from the substrate provide the power line rejection essential in systems generating a trigger from large numbers of channels. (orig.)
DEFF Research Database (Denmark)
Jepsen, Kim Stokholm; Mikkelsen, Benny; Vaa, Michael
1998-01-01
Simultaneous all-optical add and drop multiplexing of a 40-Gbit/s OTDM signal using a monolithically integrated semiconductor optical amplifier/Mach Zehnder interferometer (SOA-MZI) is demonstrated. While maintaining a penalty of 1.3 dB for the add operation the sensitivity for the demultiplexed ...... signal is -34.4 dBm...
Temperature Characteristics of Monolithically Integrated Wavelength-Selectable Light Sources
International Nuclear Information System (INIS)
Han Liang-Shun; Zhu Hong-Liang; Zhang Can; Ma Li; Liang Song; Wang Wei
2013-01-01
The temperature characteristics of monolithically integrated wavelength-selectable light sources are experimentally investigated. The wavelength-selectable light sources consist of four distributed feedback (DFB) lasers, a multimode interferometer coupler, and a semiconductor optical amplifier. The oscillating wavelength of the DFB laser could be modulated by adjusting the device operating temperature. A wavelength range covering over 8.0nm is obtained with stable single-mode operation by selecting the appropriate laser and chip temperature. The thermal crosstalk caused by the lateral heat spreading between lasers operating simultaneously is evaluated by oscillating-wavelength shift. The thermal crosstalk approximately decreases exponentially as the increasing distance between lasers
Energy Technology Data Exchange (ETDEWEB)
Zhang Xuelian; Yan Jun; Shi Yin [Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China); Foster, Dai Fa, E-mail: xlzhang@semi.ac.c [Department of Electrical and Computer Engineering, Auburn University, Auburn, AL 36849-5201 (United States)
2009-01-15
A 5.2 GHz variable-gain amplifier (VGA) and a power amplifier (PA) driver are designed for WLAN IEEE 802.11a monolithic RFIC. The VGA and the PA driver are implemented in a 50 GHz 0.35 mum SiGe BiCMOS technology and occupy 1.12 x 1.25 mm{sup 2} die area. The VGA with effective temperature compensation is controlled by 5 bits and has a gain range of 34 dB. The PA driver with tuned loads utilizes a differential input, single-ended output topology, and the tuned loads resonate at 5.2 GHz. The maximum overall gain of the VGA and the PA driver is 29 dB with the output third-order intercept point (OIP3) of 11 dBm. The gain drift over the temperature varying from -30 to 85 deg. C converges within +-3 dB. The total current consumption is 45 mA under a 2.85 V power supply.
A design concept for an MMIC (Monolithic Microwave Integrated Circuit) microstrip phased array
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.
A fast large dynamic range shaping amplifier for particle detector front-end
International Nuclear Information System (INIS)
Rivetti, Angelo; Delaurenti, Paolo
2007-01-01
The paper describes a fast shaping amplifier with rail-to-rail output swing. The circuit is based on a CMOS operational amplifier with a class AB output stage. A baseline holder, incorporating a closed-loop unity gain buffer with slew rate limitation, performs the AC coupling with the preamplifier and guarantees a baseline shift smaller than 3 mV for unipolar output pulses of 3 V and 10 MHz rate
Peng, Xiang; Kim, Kyungbum; Mielke, Michael; Jennings, Stephen; Masor, Gordon; Stohl, Dave; Chavez-Pirson, Arturo; Nguyen, Dan T; Rhonehouse, Dan; Zong, Jie; Churin, Dmitriy; Peyghambarian, N
2013-10-21
A novel monolithic fiber-optic chirped pulse amplification (CPA) system for high energy, femtosecond pulse generation is proposed and experimentally demonstrated. By employing a high gain amplifier comprising merely 20 cm of high efficiency media (HEM) gain fiber, an optimal balance of output pulse energy, optical efficiency, and B-integral is achieved. The HEM amplifier is fabricated from erbium-doped phosphate glass fiber and yields gain of 1.443 dB/cm with slope efficiency >45%. We experimentally demonstrate near diffraction-limited beam quality and near transform-limited femtosecond pulse quality at 1.55 µm wavelength. With pulse energy >100 µJ and pulse duration of 636 fs (FWHM), the peak power is estimated to be ~160 MW. NAVAIR Public Release Distribution Statement A-"Approved for Public release; distribution is unlimited".
International Nuclear Information System (INIS)
Lee, Jeongmi; Park, Jung Hag; Jang, Myung Duk
2012-01-01
Sulfonated cellulose tris(3,5-dimethylphenyl carbamate) (SCDMPC)-coated zirconia monolith (ZM) was used as the chiral stationary phase in capillary electro chromatography for separation of enantiomers of ten chiral compounds in acetonitrile (ACN)-phosphate buffer mixtures as the eluent. Influences of the ACN content, buffer concentration and pH on chiral separation have been investigated. Separation data on SCDMPC-ZM have been compared with those on CDMPC-ZM. Resolution factors were better on SCDMPC-ZM than CDMPC-ZM while retention factors were in general shorter on the former than the latter. Best chiral resolutions on SCDMPC-ZM were obtained with the eluent of 50% ACN containing 50 mM phosphate at pH around 4
International Nuclear Information System (INIS)
Wang, Y; Gong, M; Yan, P; Huang, L; Li, D
2009-01-01
A monolithic Nd:YAG microchip laser with [110] cut Cr 4+ :YAG is presented. The output beam is linearly polarized with polarization ratio higher than 100:1. The polarization direction is stable, independent of pump power, crystal temperature, LD temperature. In single longitudinal mode operation, stable 259 ps pulses at 2.5 kHz with 82 kW peak power and diffraction limited beam mode are output. With a simple and compact one-pass Nd:YVO 4 amplifier, 144 kW peak power is achieved. Single longitudinal and fundamental transverse mode is kept after passing through the amplifier stage. The microchip laser can be operated in two longitudinal modes with two sets of output pulses by increasing the pump power
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.
International Nuclear Information System (INIS)
Kovar, D.; King, B.H.; Trice, R.W.; Halloran, J.W.
1997-01-01
Fibrous monolithic ceramics are an example of a laminate in which a controlled, three-dimensional structure has been introduced on a submillimeter scale. This unique structure allows this all-ceramic material to fail in a nonbrittle manner. Materials have been fabricated and tested with a variety of architectures. The influence on mechanical properties at room temperature and at high temperature of the structure of the constituent phases and the architecture in which they are arranged are discussed. The elastic properties of these materials can be effectively predicted using existing models. These models also can be extended to predict the strength of fibrous monoliths with an arbitrary orientation and architecture. However, the mechanisms that govern the energy absorption capacity of fibrous monoliths are unique, and experimental results do not follow existing models. Energy dissipation occurs through two dominant mechanisms--delamination of the weak interphases and then frictional sliding after cracking occurs. The properties of the constituent phases that maximize energy absorption are discussed. In this article, the authors examine the structure of Si 3 N 4 -BN fibrous monoliths from the submillimeter scale of the crack-deflecting cell-cell boundary features to the nanometer scale of the BN cell boundaries
Superconducting NbN single-photon detectors on GaAs with an AlN buffer layer
Energy Technology Data Exchange (ETDEWEB)
Schmidt, Ekkehart; Merker, Michael; Ilin, Konstantin; Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme (IMS), Karlsruher Institut fuer Technologie, Hertzstrasse 16, 76187 Karlsruhe (Germany)
2015-07-01
GaAs is the material of choice for photonic integrated circuits. It allows the monolithic integration of single-photon sources like quantum dots, waveguide based optical circuits and detectors like superconducting nanowire single-photon detectors (SNSPDs) onto one chip. The growth of high quality NbN films on GaAs is challenging, due to natural occurring surface oxides and the large lattice mismatch of about 27%. In this work, we try to overcome these problems by the introduction of a 10 nm AlN buffer layer. Due to the buffer layer, the critical temperature of 6 nm thick NbN films was increased by about 1.5 K. Furthermore, the critical current density at 4.2 K of NbN flim deposited onto GaAs with AlN buffer is 50% higher than of NbN film deposited directly onto GaAs substrate. We successfully fabricated NbN SNSPDs on GaAs with a AlN buffer layer. SNSPDs were patterned using electron-beam lithography and reactive-ion etching techniques. Results on the study of detection efficiency and jitter of a NbN SNSPD on GaAs, with and without AlN buffer layer will be presented and discussed.
Monolithic exploding foil initiator
Welle, Eric J; Vianco, Paul T; Headley, Paul S; Jarrell, Jason A; Garrity, J. Emmett; Shelton, Keegan P; Marley, Stephen K
2012-10-23
A monolithic exploding foil initiator (EFI) or slapper detonator and the method for making the monolithic EFI wherein the exploding bridge and the dielectric from which the flyer will be generated are integrated directly onto the header. In some embodiments, the barrel is directly integrated directly onto the header.
A high-linearity InGaP/GaAs HBT power amplifier for IEEE 802.11a/n
International Nuclear Information System (INIS)
Cui Jie; Chen Lei; Kang Chunlei; Shi Jia; Zhang Xuguang; Ai Baoli; Liu Yi
2013-01-01
A three-stage 4.8–6 GHz monolithic power amplifier (PA) compatible with IEEE 802.11a/n designed based on an advanced 2 μm InGaP/GaAs hetero-junction bipolar transistor (HBT) process is presented. The PA integrates input matching and closed-loop power control circuits on chip. Under 3.3 V DC bias, the amplifier achieves a ∼31 dB small signal gain, excellent wide band input and output matching among overall 1.2 GHz bandwidth, and up to 24.5 dBm linear output power below EVM 3% with IEEE 802.11a 64QAM OFDM input signal. (semiconductor integrated circuits)
GaAs Wideband Low Noise Amplifier Design for Breast Cancer Detection System
DEFF Research Database (Denmark)
Yan, Lei; Krozer, Viktor; Delcourt, Sebastien
2009-01-01
Modern wideband systems require low-noise receivers with bandwidth approaching 10 GHz. This paper presents ultra-wideband stable low-noise amplifier MMIC with cascode and source follower buffer configuration using GaAs technology. Source degeneration, gate and shunt peaking inductors are used...
Semipolar InGaN quantum-well laser diode with integrated amplifier for visible light communications
Shen, Chao
2018-02-14
GaN-based semiconductor optical amplifier (SOA) and its integration with laser diode (LD) is an essential building block yet to be demonstrated for III-nitride photonic integrated circuits (PICs) at visible wavelength. This paper presents the InGaN/GaN quantum well (QW) based dual-section LD consisting of integrated amplifier and laser gain regions fabricated on a semipolar GaN substrate. The threshold current in the laser gain region was favorably reduced from 229mA to 135mA at SOA driving voltages, VSOA, of 0V and 6.25V, respectively. The amplification effect was measured based on a large gain of 5.7 dB at VSOA = 6.25V from the increased optical output power of 8.2 mW to 30.5 mW. Such integrated amplifier can be modulated to achieve Gbps data communication using on-off keying technique. The monolithically integrated amplifier-LD paves the way towards the III-nitride on-chip photonic system, providing a compact, low-cost, and multi-functional solution for applications such as smart lighting and visible light communications.
Semipolar InGaN quantum-well laser diode with integrated amplifier for visible light communications
Shen, Chao; Ng, Tien Khee; Lee, Changmin; Nakamura, Shuji; Speck, James S.; DenBaars, Steven P.; Alyamani, Ahmed Y.; El-Desouki, Munir M.; Ooi, Boon S.
2018-01-01
GaN-based semiconductor optical amplifier (SOA) and its integration with laser diode (LD) is an essential building block yet to be demonstrated for III-nitride photonic integrated circuits (PICs) at visible wavelength. This paper presents the InGaN/GaN quantum well (QW) based dual-section LD consisting of integrated amplifier and laser gain regions fabricated on a semipolar GaN substrate. The threshold current in the laser gain region was favorably reduced from 229mA to 135mA at SOA driving voltages, VSOA, of 0V and 6.25V, respectively. The amplification effect was measured based on a large gain of 5.7 dB at VSOA = 6.25V from the increased optical output power of 8.2 mW to 30.5 mW. Such integrated amplifier can be modulated to achieve Gbps data communication using on-off keying technique. The monolithically integrated amplifier-LD paves the way towards the III-nitride on-chip photonic system, providing a compact, low-cost, and multi-functional solution for applications such as smart lighting and visible light communications.
Monolithic array of 32 SPAD pixels for single-photon imaging at high frame rates
International Nuclear Information System (INIS)
Tisa, Simone; Guerrieri, Fabrizio; Zappa, Franco
2009-01-01
We present a single-chip monolithic array of 32 Single-Photon Avalanche Diodes (SPAD) and associated electronics for imaging at high frame rates and high sensitivity. Photodetectors, front-end circuitry and control electronics used to manage the array are monolithically integrated on the same chip in a standard 0.35 μm CMOS high-voltage technology. The array is composed of 32 'smart' pixels working in photon counting mode and functioning in a parallel fashion. Every cell comprises of an integrated SPAD photodetector, a novel quenching circuit named as Variable Load Quenching Circuit (VLQC), counting electronics and a buffer memory. Proper ancillary electronics that perform the arbitration of photon counts between two consecutive frames is integrated as well. Thanks to the presence of in-pixel memory registers, the inter-frame dead time between subsequent frames is limited to few nanoseconds. Since integration and download are performed simultaneously and the array can be addressed like a standard digital memory, the achievable maximum frame rate is very high in the order of hundreds of thousands of frame/s.
The multichannel amplifier/discriminator CMOS ASIC for visual light photon counters
International Nuclear Information System (INIS)
Baturitsky, M.A.; Yurenya, Yu.P.Yu.P.
2002-01-01
The 18-channel CMOS custom monolithic amplifier/discriminator ASIC was designed as a front-end electronics chip for Visual Light Photon Counters which convert photons from scintillation fibre/strip detectors to electrical signals. One ASICs channel contains a charge-sensitive preamplifier, a discriminator to mark the arrival time of signals, and a charge divider to provide analog outputs for analog-to-digital conversion being performed by SVX2. The ASIC is proposed as one of the variants for possible future front-end electronics upgrading the D0 Central Fibre Tracker, Central and Forward Pre-Showers (Fermilab, Batavia, USA)
International Nuclear Information System (INIS)
Baransel, Asyun; Dugler, Hikmat E.; Tokdemir, Mehmet
2004-01-01
The polymerase chain reaction (PCR) - based DNA amplification fingerprinting (DAF) or randomly amplified polymorphic DNA (RAPD) is based on a strategy using a single arbitrary oligonucleotide primer to generate anonymous amplification of genomic DNA. On this basic strategy, in this study, we aimed to test individual differences and usefulness of 2 basic primers (5-CGCGCCGG-3 and 5-TGCCGAGCTG-3) and examined whether there is a positive effect on results of 10 x PCR buffer with ammonium sulfate. A new approach in DNA fingerprinting, 10 x PCR buffer with ammonium sulfate, is presented in the study. Primers with single 8 and 10 nucleotides in length and 2 different PCR buffers with or without ammonium sulfate were used to identify 135 volunteers with no blood relationship. This study was carried out at the Pharmacology Laboratory, University of Gaziantep, School of Medicine, Turkey between 1999 and 2000. An average of 10 major bands representing 500-1500 base pair (bp) in length was determined as amplified DNA products on standard agarose gels for these volunteers. The use of ammonium sulfate in 10 x PCR buffers has increased to 92% success ratio of individual difference obtained from the 8 nucleotides primer. With this study, more reliable results can be obtained by using ammonium sulfate in 10 x PCR buffers. (author)
Monolithic PM Raman fiber laser at 1679 nm for Raman amplification at 1810 nm
DEFF Research Database (Denmark)
Svane, Ask Sebastian; Rottwitt, Karsten
2013-01-01
Stimulated Raman scattering (SRS) has been subject to much attention within the field of fiber lasers and amplifiers as it provides an extended wavelength coverage in comparison to rare-earth based devices. Motivated by the projected capacity crunch [1], different approaches are being explored...... demonstrate a monolithic RM Raman fiber laser (RFL), which acts as a pump for a Raman amplifier (RA) at 1810 nm. The lasing wavelength of a RFL, thus also for a RA, can in principle be designed arbitrarily within the entire wavelength range from the Erbium band up to the Thulium/Holmium band...... of OFS PM Raman fiber, with an estimated propagation loss of 0.42/0.46/1.3 dB/km at 1564/1679/1810 nm. The Raman gain coefficient was measured to be gR=2.66/2.35 W-1km-1 at 1679/1810 nm. The laser curve of the RFL is depicted in Fig. 1b, with a slope efficiency of 67 %. The high slope efficiency...
Microfluidic devices and methods including porous polymer monoliths
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.
Trial manufacture of an insulated amplifier
International Nuclear Information System (INIS)
Okuno, Shigeo; Matsuura, Kiyokata.
1978-10-01
Trial manufacture of an insulated amplifier was carried out. The input signals are divided by filters Th and Tl into high frequency component and low frequency component. The high frequency component drives a transformer T 1 , and secondary signals are induced. The low frequency component drives a transformer T 2 through a buffer and a modulator. The secondary signals from both transformers are recombined to make the output signals. Compensation for the frequency characteristics of the high frequency transformer and that for the effect of a filter in the demodulation circuit for low frequency component are considered. The time constant of output signals for rectangular input signals was 30 microsec, when only the low frequency part is operated. The drift of the direct current level is within 5 mV. The characteristic features of the high frequency part was also investigated. The overall characteristic features of this amplifier were good for the frequency range of 0 to 500 kHz. (Kato, T.)
A monolithic active pixel sensor for particle detection in 0.25 μm CMOS technology
International Nuclear Information System (INIS)
Velthuis, J.J.; Allport, P.P.; Casse, G.; Evans, A.; Turchetta, R.; Villani, G.
2006-01-01
We are developing CMOS monolithic active pixel sensors (MAPS) for High Energy Physics applications. We have successfully produced 3 test structures. They feature several different pixel types including: standard 3MOS, 4MOS allowing Correlated Double Sampling (CDS), charge amplifier pixels and a flexible APS (FAPS). The FAPS has a 10 deep pipeline on each pixel. This is specifically designed with the beam structure of the TESLA proposal for the Linear Collider in mind. Results of a laser test on our first device and source test results on two more recent test structures will be presented
Development of FIR arrays with integrating amplifiers
Young, Erick T.
1988-08-01
The development of optimized photoconductor arrays suitable for far infrared space astronomical applications are described. Although the primary impetus is the production of a 16 by 16 element Ge:Ga demonstration array for SIRTF, the extension of this technology to Large Deployable Reflector (LDR) is considered. The optimization of Ge:Ga and Ge:Be photoconductor materials is discussed. In collaboration with Lawrence Berkeley Laboratory, measurements of FIR photoconductors with quantum efficiencies greater than 20 percent at 100 micrometers, and dark currents below 300 electrons/s are presented. Integrating J-FET amplifier technology is discussed. The current generation of integrating amplifiers has a demonstrated read noise of less than 20 electrons for an integration time of 100 s. The design is shown for a stackable 16 x n Ge:Ga array that utilizes a 16-channel monolithic version of the J-FET integrator. A part of the design is the use of a thin, thermally insulating substrate that allows the electronics to operate at the optimum temperature of 50 K while maintaining thermal and optical isolation from the detectors at 2 K. The power dissipation for the array is less than 16 mW. The array design may particularly be applicable to high resolution imaging spectrometers for LDR.
Energy Technology Data Exchange (ETDEWEB)
Rajic, Slobodan (Knoxville, TN); Egert, Charles M. (Oak Ridge, TN); Kahl, William K. (Knoxville, TN); Snyder, Jr., William B. (Knoxville, TN); Evans, III, Boyd M. (Oak Ridge, TN); Marlar, Troy A. (Knoxville, TN); Cunningham, Joseph P. (Oak Ridge, TN)
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.
A multi-ring optical packet and circuit integrated network with optical buffering.
Furukawa, Hideaki; Shinada, Satoshi; Miyazawa, Takaya; Harai, Hiroaki; Kawasaki, Wataru; Saito, Tatsuhiko; Matsunaga, Koji; Toyozumi, Tatuya; Wada, Naoya
2012-12-17
We newly developed a 3 × 3 integrated optical packet and circuit switch-node. Optical buffers and burst-mode erbium-doped fiber amplifiers with the gain flatness are installed in the 3 × 3 switch-node. The optical buffer can prevent packet collisions and decrease packet loss. We constructed a multi-ring optical packet and circuit integrated network testbed connecting two single-ring networks and a client network by the 3 × 3 switch-node. For the first time, we demonstrated 244 km fiber transmission and 5-node hopping of multiplexed 14-wavelength 10 Gbps optical paths and 100 Gbps optical packets encapsulating 10 Gigabit Ethernet frames on the testbed. Error-free (frame error rate optical packets of various packet lengths. In addition, successful avoidance of packet collisions by optical buffers was confirmed.
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.
A Decade-Bandwidth Distributed Power Amplifier MMIC Using 0.25 μm GaN HEMT Technology
Directory of Open Access Journals (Sweden)
Dong-Hwan Shin
2017-10-01
Full Text Available This study presents a 2–20 GHz monolithic distributed power amplifier (DPA using a 0.25 μm AlGaN/GaN on SiC high electron mobility transistor (HEMT technology. The gate width of the HEMT was selected after considering the input capacitance of the unit cell that guarantees decade bandwidth. To achieve high output power using small transistors, a 12-stage DPA was designed with a nonuniform drain line impedance to provide optimal output power matching. The maximum operating frequency of the proposed DPA is above 20 GHz, which is higher than those of other DPAs manufactured with the same gate-length process. The measured output power and power-added efficiency of the DPA monolithic microwave integrated circuit (MMIC are 35.3–38.6 dBm and 11.4%–31%, respectively, for 2–20 GHz.
Monolithic solid-state lasers for spaceflight
Krainak, Michael A.; Yu, Anthony W.; Stephen, Mark A.; Merritt, Scott; Glebov, Leonid; Glebova, Larissa; Ryasnyanskiy, Aleksandr; Smirnov, Vadim; Mu, Xiaodong; Meissner, Stephanie; Meissner, Helmuth
2015-02-01
A new solution for building high power, solid state lasers for space flight is to fabricate the whole laser resonator in a single (monolithic) structure or alternatively to build a contiguous diffusion bonded or welded structure. Monolithic lasers provide numerous advantages for space flight solid-state lasers by minimizing misalignment concerns. The closed cavity is immune to contamination. The number of components is minimized thus increasing reliability. Bragg mirrors serve as the high reflector and output coupler thus minimizing optical coatings and coating damage. The Bragg mirrors also provide spectral and spatial mode selection for high fidelity. The monolithic structure allows short cavities resulting in short pulses. Passive saturable absorber Q-switches provide a soft aperture for spatial mode filtering and improved pointing stability. We will review our recent commercial and in-house developments toward fully monolithic solid-state lasers.
Carrasco-Correa, Enrique Javier; Ramis-Ramos, Guillermo; Herrero-Martínez, José Manuel
2013-07-12
Epinephrine-bonded polymeric monoliths for capillary electrochromatography (CEC) were developed by nucleophilic substitution reaction of epoxide groups of poly(glycidyl-methacrylate-co-ethylenedimethacrylate) (poly(GMA-co-EDMA)) monoliths using epinephrine as nucleophilic reagent. The ring opening reaction under dynamic conditions was optimized. Successful chemical modification of the monolith surface was ascertained by in situ Raman spectroscopy characterization. In addition, the amount of epinephrine groups that was bound to the monolith surface was evaluated by oxidation of the catechol groups with Ce(IV), followed by spectrophotometric measurement of unreacted Ce(IV). About 9% of all theoretical epoxide groups of the parent monolith were bonded to epinephrine. The chromatographic behavior of the epinephrine-bonded monolith in CEC conditions was assessed with test mixtures of alkyl benzenes, aniline derivatives and substituted phenols. In comparison to the poly(GMA-co-EDMA) monoliths, the epinephrine-bonded monoliths exhibited a much higher retention and slight differences in selectivity. The epinephrine-bonded monolith was further modified by oxidation with a Ce(IV) solution and compared with the epinephrine-bonded monoliths. The resulting monolithic stationary phases were evaluated in terms of reproducibility, giving RSD values below 9% in the parameters investigated. Copyright © 2013 Elsevier B.V. All rights reserved.
Application-specific architectures of CMOS monolithic active pixel sensors
Energy Technology Data Exchange (ETDEWEB)
Szelezniak, Michal [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]. E-mail: michal.szelezniak@ires.in2p3.fr; Besson, Auguste [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Claus, Gilles; Colledani, Claude; [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Degerli, Yavuz [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Deptuch, Grzegorz [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Deveaux, Michael [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Dorokhov, Andrei [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Dulinski, Wojciech [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Fourches, Nicolas [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Goffe, Mathieu [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Grandjean, Damien; Guilloux, Fabrice [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Heini, Sebastien [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)]|[GSI, Planckstrasse 1, Darmstadt 64291 (Germany); Himmi, Abdelkader [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Hu, Christine [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France); Jaaskelainen, Kimmo; Li, Yan; Lutz, Pierre; Orsini, Fabienne [CEA Saclay, DAPNIA, Gif-sur-Yvette Cedex (France); Pellicioli, Michel; Shabetai, Alexandre; Valin, Isabelle; Winter, Marc [Institute de Recherches Subatomiques, 23 rue du Loess, Strasbourg 67037 Cedex 02 (France)
2006-11-30
Several development directions intended to adapt and optimize monolithic active pixel sensors for specific applications are presented in this work. The first example, compatible with the STAR microvertex upgrade, is based on a simple two-transistor pixel circuitry. It is suited for a long integration time, room-temperature operation and minimum power dissipation. In another approach for this application, a specific readout method is proposed, allowing optimization of the integration time independently of the full frame-readout time. The circuit consists of an in-pixel front-end voltage amplifier, with a gain on the order of five, followed by two analog memory cells. The extended version of this scheme, based on the implementation of more memory cells per pixel, is the solution considered for the outer layers of a microvertex detector at the international linear collider. For the two innermost layers, a circuit allowing fast frame scans together with on-line, on-chip data sparsification is proposed. The first results of this prototype demonstrate that the fixed pattern dispersion is reduced below a noise level of 15 e{sup -}, allowing the use of a single comparator or a low-resolution ADC per pixel column. A common element for most of the mentioned readout schemes is a low-noise, low power consumption, layout efficient in-pixel amplifier. A review of possible solutions for this element together with some experimental results is presented.
High linearity 5.2-GHz power amplifier MMIC using CPW structure technology with a linearizer circuit
International Nuclear Information System (INIS)
Wu Chiasong; Lin Tah-Yeong; Wu Hsien-Ming
2010-01-01
A built-in linearizer was applied to improve the linearity in a 5.2-GHz power amplifier microwave monolithic integrated circuit (MMIC), which was undertaken with 0.15-μm AlGaAs/InGaAs D-mode PHEMT technology. The power amplifier (PA) was studied taking into account the linearizer circuit and the coplanar waveguide (CPW) structures. Based on these technologies, the power amplifier, which has a chip size of 1.44 x 1.10 mm 2 , obtained an output power of 13.3 dBm and a power gain of 14 dB in the saturation region. An input third-order intercept point (HP 3 ) of -3 dBm, an output third-order intercept point (OIP 3 ) of 21.1 dBm and a power added efficiency (PAE) of 22% were attained, respectively. Finally, the overall power characterization exhibited high gain and high linearity, which illustrates that the power amplifier has a compact circuit size and exhibits favorable RF characteristics. This power circuit demonstrated high RF characterization and could be used for microwave power circuit applications at 5.2 GHz. (semiconductor integrated circuits)
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.
Buffer capacity of biologics--from buffer salts to buffering by antibodies.
Karow, Anne R; Bahrenburg, Sven; Garidel, Patrick
2013-01-01
Controlling pH is essential for a variety of biopharmaceutical process steps. The chemical stability of biologics such as monoclonal antibodies is pH-dependent and slightly acidic conditions are favorable for stability in a number of cases. Since control of pH is widely provided by added buffer salts, the current study summarizes the buffer characteristics of acetate, citrate, histidine, succinate, and phosphate buffers. Experimentally derived values largely coincide with values calculated from a model that had been proposed in 1922 by van Slyke. As high concentrated protein formulations become more and more prevalent for biologics, the self-buffering potential of proteins becomes of relevance. The current study provides information on buffer characteristics for pH ranges down to 4.0 and up to 8.0 and shows that a monoclonal antibody at 50 mg/mL exhibits similar buffer capacity as 6 mM citrate or 14 mM histidine (pH 5.0-6.0). Buffer capacity of antibody solutions scales linearly with protein concentration up to more than 200 mg/mL. At a protein concentration of 220 mg/mL, the buffer capacity resembles the buffer capacity of 30 mM citrate or 50 mM histidine (pH 5.0-6.0). The buffer capacity of monoclonal antibodies is practically identical at the process relevant temperatures 5, 25, and 40°C. Changes in ionic strength of ΔI=0.15, in contrast, can alter the buffer capacity up to 35%. In conclusion, due to efficient self-buffering by antibodies in the pH range of favored chemical stability, conventional buffer excipients could be dispensable for pH stabilization of high concentrated protein solutions. Copyright © 2013 American Institute of Chemical Engineers.
Synthesis of Porous Carbon Monoliths Using Hard Templates.
Klepel, Olaf; Danneberg, Nina; Dräger, Matti; Erlitz, Marcel; Taubert, Michael
2016-03-21
The preparation of porous carbon monoliths with a defined shape via template-assisted routes is reported. Monoliths made from porous concrete and zeolite were each used as the template. The porous concrete-derived carbon monoliths exhibited high gravimetric specific surface areas up to 2000 m²·g -1 . The pore system comprised macro-, meso-, and micropores. These pores were hierarchically arranged. The pore system was created by the complex interplay of the actions of both the template and the activating agent as well. On the other hand, zeolite-made template shapes allowed for the preparation of microporous carbon monoliths with a high volumetric specific surface area. This feature could be beneficial if carbon monoliths must be integrated into technical systems under space-limited conditions.
Energy Technology Data Exchange (ETDEWEB)
Liang, Z., E-mail: zhijun.liang@cern.ch [University of California Santa Cruz, Santa Cruz Institute for Particle Physics (SCIPP) (United States); Institute of High Energy Physics, Beijing (China); Affolder, A. [University of Liverpool (United Kingdom); Arndt, K. [University of Oxford (United Kingdom); Bates, R. [SUPA – School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Benoit, M.; Di Bello, F. [University of Geneva (Switzerland); Blue, A. [SUPA – School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Bortoletto, D. [University of Oxford (United Kingdom); Buckland, M. [University of Liverpool (United Kingdom); CERN, European Center for Nuclear Research (Switzerland); Buttar, C. [SUPA – School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Caragiulo, P. [SLAC National Accelerator Laboratory (United States); Das, D.; Dopke, J. [Rutherford Appleton Laboratory, Didcot (United Kingdom); Dragone, A. [SLAC National Accelerator Laboratory (United States); Ehrler, F. [Karlsruhe Institute of Technology (Germany); Fadeyev, V.; Galloway, Z.; Grabas, H. [University of California Santa Cruz, Santa Cruz Institute for Particle Physics (SCIPP) (United States); Gregor, I.M. [Deutsches Elektronen-Synchrotron (Germany); Grenier, P. [SLAC National Accelerator Laboratory (United States); and others
2016-09-21
This paper focuses on the performance of analog readout electronics (built-in amplifier) integrated on the high-voltage (HV) CMOS silicon sensor chip, as well as its radiation hardness. Since the total collected charge from minimum ionizing particle (MIP) for the CMOS sensor is 10 times lower than for a conventional planar sensor, it is crucial to integrate a low noise built-in amplifier on the sensor chip to improve the signal to noise ratio of the system. As part of the investigation for the ATLAS strip detector upgrade, a test chip that comprises several pixel arrays with different geometries, as well as standalone built-in amplifiers and built-in amplifiers in pixel arrays has been fabricated in a 0.35 μm high-voltage CMOS process. Measurements of the gain and the noise of both the standalone amplifiers and built-in amplifiers in pixel arrays were performed before and after gamma radiation of up to 60 Mrad. Of special interest is the variation of the noise as a function of the sensor capacitance. We optimized the configuration of the amplifier for a fast rise time to adapt to the LHC bunch crossing period of 25 ns, and measured the timing characteristics including jitter. Our results indicate an adequate amplifier performance for monolithic structures used in HV-CMOS technology. The results have been incorporated in the next submission of a large-structure chip.
Wang, Y; Harrison, M; Clark, B J
2006-02-10
An optimization strategy for the separation of an acidic mixture by employing a monolithic stationary phase is presented, with the aid of experimental design and response surface methodology (RSM). An orthogonal array design (OAD) OA(16) (2(15)) was used to choose the significant parameters for the optimization. The significant factors were optimized by using a central composite design (CCD) and the quadratic models between the dependent and the independent parameters were built. The mathematical models were tested on a number of simulated data set and had a coefficient of R(2) > 0.97 (n = 16). On applying the optimization strategy, the factor effects were visualized as three-dimensional (3D) response surfaces and contour plots. The optimal condition was achieved in less than 40 min by using the monolithic packing with the mobile phase of methanol/20 mM phosphate buffer pH 2.7 (25.5/74.5, v/v). The method showed good agreement between the experimental data and predictive value throughout the studied parameter space and were suitable for optimization studies on the monolithic stationary phase for acidic compounds.
Nano-Doped Monolithic Materials for Molecular Separation
Directory of Open Access Journals (Sweden)
Caleb Acquah
2017-01-01
Full Text Available Monoliths are continuous adsorbents that can easily be synthesised to possess tuneable meso-/macropores, convective fluid transport, and a plethora of chemistries for ligand immobilisation. They are grouped into three main classes: organic, inorganic, and hybrid, based on their chemical composition. These classes may also be differentiated by their unique morphological and physicochemical properties which are significantly relevant to their specific separation applications. The potential applications of monoliths for molecular separation have created the need to enhance their characteristic properties including mechanical strength, electrical conductivity, and chemical and thermal stability. An effective approach towards monolith enhancement has been the doping and/or hybridization with miniaturized molecular species of desirable functionalities and characteristics. Nanoparticles are usually preferred as dopants due to their high solid phase dispersion features which are associated with improved intermolecular adsorptive interactions. Examples of such nanomaterials include, but are not limited to, carbon-based, silica-based, gold-based, and alumina nanoparticles. The incorporation of these nanoparticles into monoliths via in situ polymerisation and/or post-modification enhances surface adsorption for activation and ligand immobilisation. Herein, insights into the performance enhancement of monoliths as chromatographic supports by nanoparticles doping are presented. In addition, the potential and characteristics of less common nanoparticle materials such as hydroxyapatite, ceria, hafnia, and germania are discussed. The advantages and challenges of nanoparticle doping of monoliths are also discussed.
Monolith electroplating process
Agarrwal, Rajev R.
2001-01-01
An electroplating process for preparing a monolith metal layer over a polycrystalline base metal and the plated monolith product. A monolith layer has a variable thickness of one crystal. The process is typically carried in molten salts electrolytes, such as the halide salts under an inert atmosphere at an elevated temperature, and over deposition time periods and film thickness sufficient to sinter and recrystallize completely the nucleating metal particles into one single crystal or crystals having very large grains. In the process, a close-packed film of submicron particle (20) is formed on a suitable substrate at an elevated temperature. The temperature has the significance of annealing particles as they are formed, and substrates on which the particles can populate are desirable. As the packed bed thickens, the submicron particles develop necks (21) and as they merge into each other shrinkage (22) occurs. Then as micropores also close (23) by surface tension, metal density is reached and the film consists of unstable metal grain (24) that at high enough temperature recrystallize (25) and recrystallized grains grow into an annealed single crystal over the electroplating time span. While cadmium was used in the experimental work, other soft metals may be used.
Translucency and Strength of High-Translucency Monolithic Zirconium-Oxide Materials
2016-05-12
Capt Todd D. Church APPROVED: Translucency and Strength of High-Translucency Monolithic Zirconium -Oxide Materials C~t) Kraig/[ Vandewalle Date...copyrighted material in the thesis/dissertation manuscript entitled: "Translucency arid Strength of High-Translucency Monolithic Zirconium -Oxide...Translucency Monolithic Zirconium -Oxide Materials Abstract Dental materials manufacturers have developed more translucent monolithic zirconium oxide
Design of CMOS CFOA Based on Pseudo Operational Transconductance Amplifier
Hassan Jassim Motlak
2015-01-01
A novel design technique employing CMOS Current Feedback Operational Amplifier (CFOA) is presented. The feature of consumption very low power in designing pseudo-OTA is used to decreasing the total power consumption of the proposed CFOA. This design approach applies pseudo-OTA as input stage cascaded with buffer stage. Moreover, the DC input offset voltage and harmonic distortion (HD) of the proposed CFOA are very low values compared with the conventional CMOS CFOA due to...
Selective oxidation of cyclohexene through gold functionalized silica monolith microreactors
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.
Preparation of polyhedral oligomeric silsesquioxane based imprinted monolith.
Li, Fang; Chen, Xiu-Xiu; Huang, Yan-Ping; Liu, Zhao-Sheng
2015-12-18
Polyhedral oligomeric silsesquioxane (POSS) was successfully applied, for the first time, to prepare imprinted monolithic column with high porosity and good permeability. The imprinted monolithic column was synthesized with a mixture of PSS-(1-Propylmethacrylate)-heptaisobutyl substituted (MA 0702), naproxon (template), 4-vinylpyridine, and ethylene glycol dimethacrylate, in ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4). The influence of synthesis parameters on the retention factor and imprinting effect, including the amount of MA 0702, the ratio of template to monomer, and the ratio of monomer to crosslinker, was investigated. The greatest imprinting factor on the imprinted monolithic column prepared with MA 0702 was 22, about 10 times higher than that prepared in absence of POSS. The comparisons between MIP monoliths synthesized with POSS and without POSS were made in terms of permeability, column efficiency, surface morphology and pore size distribution. In addition, thermodynamic and Van Deemter analysis were used to evaluate the POSS-based MIP monolith. Copyright © 2015 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
Ma Li; Zhu Hong-Liang; Liang Song; Zhao Ling-Juan; Chen Ming-Hua
2013-01-01
Monolithic integration of four 1.55-μm-range InGaAsP/InP distributed feedback (DFB) lasers using varied ridge width with a 4 × 1-multimode-interference (MMI) optical combiner and a semiconductor optical amplifier (SOA) is demonstrated. The average output power and the threshold current are 1.8 mW and 35 mA, respectively, when the injection current of the SOA is 100 mA, with a side mode suppression ratio (SMSR) exceeding 40 dB. The four channels have a 1-nm average channel spacing and can operate separately or simultaneously. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)
Protective Skins for Aerogel Monoliths
Leventis, Nicholas; Johnston, James C.; Kuczmarski, Maria A.; Meador, Ann B.
2007-01-01
A method of imparting relatively hard protective outer skins to aerogel monoliths has been developed. Even more than aerogel beads, aerogel monoliths are attractive as thermal-insulation materials, but the commercial utilization of aerogel monoliths in thermal-insulation panels has been inhibited by their fragility and the consequent difficulty of handling them. Therefore, there is a need to afford sufficient protection to aerogel monoliths to facilitate handling, without compromising the attractive bulk properties (low density, high porosity, low thermal conductivity, high surface area, and low permittivity) of aerogel materials. The present method was devised to satisfy this need. The essence of the present method is to coat an aerogel monolith with an outer polymeric skin, by painting or spraying. Apparently, the reason spraying and painting were not attempted until now is that it is well known in the aerogel industry that aerogels collapse in contact with liquids. In the present method, one prevents such collapse through the proper choice of coating liquid and process conditions: In particular, one uses a viscous polymer precursor liquid and (a) carefully controls the amount of liquid applied and/or (b) causes the liquid to become cured to the desired hard polymeric layer rapidly enough that there is not sufficient time for the liquid to percolate into the aerogel bulk. The method has been demonstrated by use of isocyanates, which, upon exposure to atmospheric moisture, become cured to polyurethane/polyurea-type coats. The method has also been demonstrated by use of commercial epoxy resins. The method could also be implemented by use of a variety of other resins, including polyimide precursors (for forming high-temperature-resistant protective skins) or perfluorinated monomers (for forming coats that impart hydrophobicity and some increase in strength).
Directory of Open Access Journals (Sweden)
R. Makri
2002-01-01
quadrature coupler and a Wilkinson one in order to reduce size. Finally, a two stages low noise amplifier was designed with the use of H40 GaAs process in order the differences between the relevant designs to be explored. The key specifications for this MMIC LNA include operation at 10 GHz with a total gain of 17 dB while the noise figure is less than 1.5 dB.
Frontend Receiver Electronics for High Frequency Monolithic CMUT-on-CMOS Imaging Arrays
Gurun, Gokce; Hasler, Paul; Degertekin, F. Levent
2012-01-01
This paper describes the design of CMOS receiver electronics for monolithic integration with capacitive micromachined ultrasonic transducer (CMUT) arrays for high-frequency intravascular ultrasound imaging. A custom 8-inch wafer is fabricated in a 0.35 μm two-poly, four-metal CMOS process and then CMUT arrays are built on top of the application specific integrated circuits (ASICs) on the wafer. We discuss advantages of the single-chip CMUT-on-CMOS approach in terms of receive sensitivity and SNR. Low-noise and high-gain design of a transimpedance amplifier (TIA) optimized for a forward-looking volumetric-imaging CMUT array element is discussed as a challenging design example. Amplifier gain, bandwidth, dynamic range and power consumption trade-offs are discussed in detail. With minimized parasitics provided by the CMUT-on-CMOS approach, the optimized TIA design achieves a 90 fA/√Hz input referred current noise, which is less than the thermal-mechanical noise of the CMUT element. We show successful system operation with a pulse-echo measurement. Transducer noise-dominated detection in immersion is also demonstrated through output noise spectrum measurement of the integrated system at different CMUT bias voltages. A noise figure of 1.8 dB is obtained in the designed CMUT bandwidth of 10 MHz to 20 MHz. PMID:21859585
Advanced Gasification Mercury/Trace Metal Control with Monolith Traps
Energy Technology Data Exchange (ETDEWEB)
Musich, Mark; Swanson, Michael; Dunham, Grant; Stanislowski, Joshua
2010-10-05
Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m{sup 3} (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m{sup 3} (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most
ADVANCED GASIFICATION MERCURY/TRACE METAL CONTROL WITH MONOLITH TRAPS
Energy Technology Data Exchange (ETDEWEB)
Mark A. Musich; Michael L. Swanson; Grant E. Dunham; Joshua J. Stanislowski
2010-07-31
Two Corning monoliths and a non-carbon-based material have been identified as potential additives for mercury capture in syngas at temperatures above 400°F and pressure of 600 psig. A new Corning monolith formulation, GR-F1-2189, described as an active sample appeared to be the best monolith tested to date. The Corning SR Liquid monolith concept continues to be a strong candidate for mercury capture. Both monolith types allowed mercury reduction to below 5-μg/m3 (~5 ppb), a current U.S. Department of Energy (DOE) goal for trace metal control. Preparation methods for formulating the SR Liquid monolith impacted the ability of the monolith to capture mercury. The Energy & Environmental Research Center (EERC)-prepared Noncarbon Sorbents 1 and 2 appeared to offer potential for sustained and significant reduction of mercury concentration in the simulated fuel gas. The Noncarbon Sorbent 1 allowed sustained mercury reduction to below 5-μg/m3 (~5 ppb). The non-carbon-based sorbent appeared to offer the potential for regeneration, that is, desorption of mercury by temperature swing (using nitrogen and steam at temperatures above where adsorption takes place). A Corning cordierite monolith treated with a Group IB metal offered limited potential as a mercury sorbent. However, a Corning carbon-based monolith containing prereduced metallic species similar to those found on the noncarbon sorbents did not exhibit significant or sustained mercury reduction. EERC sorbents prepared with Group IB and IIB selenide appeared to have some promise for mercury capture. Unfortunately, these sorbents also released Se, as was evidenced by the measurement of H2Se in the effluent gas. All sorbents tested with arsine or hydrogen selenide, including Corning monoliths and the Group IB and IIB metal-based materials, showed an ability to capture arsine or hydrogen selenide at 400°F and 600 psig. Based on current testing, the noncarbon metal-based sorbents appear to be the most effective arsine
Chaisuwan, Patcharin; Nacapricha, Duangjai; Wilairat, Prapin; Jiang, Zhengjin; Smith, Norman W
2008-06-01
This work reports the first use of a monolith with method development for the separation of tocopherol (TOH) compounds by CEC with UV detection. A pentaerythritol diacrylate monostearate-ethylene dimethacrylate (PEDAS-EDMA) monolithic column has been investigated for an optimised condition to separate alpha-, beta-, gamma- and delta-TOHs, and alpha-tocopherol acetate (TAc). The PEDAS-EDMA monolith showed a remarkably good selectivity for separation of the TOH isomers including the beta- and gamma-isomers which are not easily separated by standard C8 or C18 particle-packed columns. Retention studies indicated that an RP mechanism was involved in the separation on the PEDAS-EDMA column, but polar interactions with the underlying ester and hydroxyl groups enhanced the separation of the problematic beta- and gamma-isomers. Separation of all the compounds was achieved within 25 min using 3:10:87 v/v/v 100 mM Tris buffer (pH 9.3)/methanol/ACN as the mobile phase. The method was successfully applied to a pharmaceutical sample with recoveries from 93 to 99%. Intraday and interday precisions (%RSD) for peak area and retention time were less than 2.3. LODs for all four TOHs and TAc were below 1 ppm.
Dopamine-imprinted monolithic column for capillary electrochromatography.
Aşır, Süleyman; Sarı, Duygu; Derazshamshir, Ali; Yılmaz, Fatma; Şarkaya, Koray; Denizli, Adil
2017-11-01
A dopamine-imprinted monolithic column was prepared and used in capillary electrochromatography as stationary phase for the first time. Dopamine was selectively separated from aqueous solution containing the competitor molecule norepinephrine, which is similar in size and shape to the template molecule. Morphology of the dopamine-imprinted column was observed by scanning electron microscopy. The influence of the organic solvent content of mobile phase, applied pressure and pH of the mobile phase on the recognition of dopamine by the imprinted monolithic column has been evaluated, and the imprinting effect in the dopamine-imprinted monolithic polymer was verified. Developed dopamine-imprinted monolithic column resulted in excellent separation of dopamine from structurally related competitor molecule, norepinephrine. Separation was achieved in a short period of 10 min, with the electrophoretic mobility of 5.81 × 10 -5 m 2 V -1 s -1 at pH 5.0 and 500 mbar pressure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ho, Ching S.; Liou, Juin J.; Georgiopoulos, Michael; Christodoulou, Christos G.
1994-03-01
This paper presents an analog circuit design and implementation for an adaptive resonance theory neural network architecture called the augmented ART1 neural network (AART1-NN). Practical monolithic operational amplifiers (Op-Amps) LM741 and LM318 are selected to implement the circuit, and a simple compensation scheme is developed to adjust the Op-Amp electrical characteristics to meet the design requirement. A 7-node prototype circuit has been designed and verified using the Pspice circuit simulator run on a Sun workstation. Results simulated from the AART1-NN circuit using the LM741, LM318, and ideal Op-Amps are presented and compared.
X-Band GaN Power Amplifier MMIC with a Third Harmonic-Tuned Circuit
Directory of Open Access Journals (Sweden)
Kyung-Tae Bae
2017-11-01
Full Text Available This paper presents an X-band GaN HEMT power amplifier with a third harmonic-tuned circuit for a higher power density per area and a higher power-added efficiency (PAE using a 0.25 μm GaN HEMT process of WIN semiconductors, Inc. The optimum load impedances at the fundamental and third harmonic frequencies are extracted from load-pull simulations at the transistor’s extrinsic plane, including the drain-source capacitance and the series drain inductance. The third harmonic-tuned circuit is effectively integrated with the output matching circuit at the fundamental frequency, without complicating the whole output matching circuit. The input matching circuit uses a lossy matching scheme, which allows a good return loss and a simple LC low-pass circuit configuration. The fabricated power amplifier monolithic microwave integrated circuit (MMIC occupies an area of 13.26 mm2, and shows a linear gain of 20 dB or more, a saturated output power of 43.2~44.7 dBm, and a PAE of 35~37% at 8.5 to 10.5 GHz.
Biomimetic small peptide functionalized affinity monoliths for monoclonal antibody purification.
Wang, Xiangyu; Xia, Donghai; Han, Hai; Peng, Kun; Zhu, Peijie; Crommen, Jacques; Wang, Qiqin; Jiang, Zhengjin
2018-08-09
The rapid development of monoclonal antibodies (mAbs) in therapeutic and diagnostic applications has necessitated the advancement of mAbs purification technologies. In this study, a biomimetic small peptide ligand 3,5-di-tert-butyl-4-hydroxybenzoic acid-Arg-Arg-Gly (DAAG) functionalized monolith was fabricated through a metal ion chelation-based multi-step approach. The resulting monolith showed good chromatographic performance. Compared with the Ni 2+ based IMAC monolith, the DAAG functionalized monolith exhibited not only excellent specificity but also higher dynamic binding capacity (DBC). The 10% DBC and 50% DBC for hIgG reached as high values as 26.0 and 34.6 mg/mL, respectively, at a ligand density of 8.8 μmol/mL, due to the high porosity and accessibility of the monolithic matrix. Moreover, the stability of the DAAG functionalized monolith in successive breakthrough experiments indicates that it has a promising potential for long-term use in mAbs purification. Finally, the DAAG functionalized monolith was successfully applied to the purification of trastuzumab or human immunoglobulin G (hIgG) from biological samples. Copyright © 2018 Elsevier B.V. All rights reserved.
Amplifier Module for 260-GHz Band Using Quartz Waveguide Transitions
Padmanabhan, Sharmila; Fung, King Man; Kangaslahti, Pekka P.; Peralta, Alejandro; Soria, Mary M.; Pukala, David M.; Sin, Seth; Samoska, Lorene A.; Sarkozy, Stephen; Lai, Richard
2012-01-01
Packaging of MMIC LNA (monolithic microwave integrated circuit low-noise amplifier) chips at frequencies over 200 GHz has always been problematic due to the high loss in the transition between the MMIC chip and the waveguide medium in which the chip will typically be used. In addition, above 200 GHz, wire-bond inductance between the LNA and the waveguide can severely limit the RF matching and bandwidth of the final waveguide amplifier module. This work resulted in the development of a low-loss quartz waveguide transition that includes a capacitive transmission line between the MMIC and the waveguide probe element. This capacitive transmission line tunes out the wirebond inductance (where the wire-bond is required to bond between the MMIC and the probe element). This inductance can severely limit the RF matching and bandwidth of the final waveguide amplifier module. The amplifier module consists of a quartz E-plane waveguide probe transition, a short capacitive tuning element, a short wire-bond to the MMIC, and the MMIC LNA. The output structure is similar, with a short wire-bond at the output of the MMIC, a quartz E-plane waveguide probe transition, and the output waveguide. The quartz probe element is made of 3-mil quartz, which is the thinnest commercially available material. The waveguide band used is WR4, from 170 to 260 GHz. This new transition and block design is an improvement over prior art because it provides for better RF matching, and will likely yield lower loss and better noise figure. The development of high-performance, low-noise amplifiers in the 180-to- 700-GHz range has applications for future earth science and planetary instruments with low power and volume, and astrophysics array instruments for molecular spectroscopy. This frequency band, while suitable for homeland security and commercial applications (such as millimeter-wave imaging, hidden weapons detection, crowd scanning, airport security, and communications), also has applications to
Directory of Open Access Journals (Sweden)
Dong‐Hwan Shin
2017-10-01
Full Text Available A 6‐GHz‐to‐18‐GHz monolithic nonuniform distributed power amplifier has been designed using the load modulation of increased series gate capacitance. This amplifier was implemented using a 0.25‐μm AlGaN/GaN HEMT process on a SiC substrate. With the proposed load modulation, we enhanced the amplifier's simulated performance by 4.8 dB in output power, and by 13.1% in power‐added efficiency (PAE at the upper limit of the bandwidth, compared with an amplifier with uniform gate coupling capacitors. Under the pulse‐mode condition of a 100‐μs pulse period and a 10% duty cycle, the fabricated power amplifier showed a saturated output power of 39.5 dBm (9 W to 40.4 dBm (11 W with an associated PAE of 17% to 22%, and input/output return losses of more than 10 dB within 6 GHz to 18 GHz.
DEFF Research Database (Denmark)
Rottwitt, Karsten
2017-01-01
The chapter provides a discussion of optical fiber amplifiers and through three sections provides a detailed treatment of three types of optical fiber amplifiers, erbium doped fiber amplifiers (EDFA), Raman amplifiers, and parametric amplifiers. Each section comprises the fundamentals including...... the basic physics and relevant in-depth theoretical modeling, amplifiers characteristics and performance data as a function of specific operation parameters. Typical applications in fiber optic communication systems and the improvement achievable through the use of fiber amplifiers are illustrated....
Fire resistance of prefabricated monolithic slab
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Gravit Marina
2017-01-01
Full Text Available A prefabricated monolithic slab (PMS has a number of valuable advantages, they allow to significantly decrease the weight of construction keeping the necessary structural-load capacity, to speed up and cheapen work conduction, to increase the heat isolating properties of an enclosure structure [1]. In order to create a design method of prefabricated monolithic slab fire-resistance, it's necessary to perform a series of PMS testing, one of which is being described in this article. Subjected to the test is a fragment of prefabricated monolithic slab with polystyrene concrete inserts along the beams with bent metal profile 250 mm thick, with a 2.7 m span loaded with evenly spread load equal to 600 kg/m2. After 3 hour testing for fire-resistance [2] no signs of construction ultimate behavior were detected.
Extended Leach Testing of Simulated LAW Cast Stone Monoliths
Energy Technology Data Exchange (ETDEWEB)
Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Benjamin D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jung, H. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2015-07-09
This report describes the results from long-term laboratory leach tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate the release of key constituents from monoliths of Cast Stone prepared with four simulated low-activity waste (LAW) liquid waste streams. Specific objectives of the Cast Stone long-term leach tests described in this report focused on four activities: 1. Extending the leaching times for selected ongoing EPA-1315 tests on monoliths made with LAW simulants beyond the conventional 63-day time period up to 609 days reported herein (with some tests continuing that will be documented later) in an effort to evaluate long-term leaching properties of Cast Stone to support future performance assessment activities. 2. Starting new EPA-1315 leach tests on archived Cast Stone monoliths made with four LAW simulants using two leachants (deionized water [DIW] and simulated Hanford Integrated Disposal Facility (IDF) Site vadose zone pore water [VZP]). 3. Evaluating the impacts of varying the iodide loading (starting iodide concentrations) in one LAW simulant (7.8 M Na Hanford Tank Waste Operations Simulator (HTWOS) Average) by manufacturing new Cast Stone monoliths and repeating the EPA-1315 leach tests using DIW and the VZP leachants. 4. Evaluating the impacts of using a non-pertechnetate form of Tc that is present in some Hanford tanks. In this activity one LAW simulant (7.8 M Na HTWOS Average) was spiked with a Tc(I)-tricarbonyl gluconate species and then solidified into Cast Stone monoliths. Cured monoliths were leached using the EPA-1315 leach protocol with DIW and VZP. The leach results for the Tc-Gluconate Cast Stone monoliths were compared to Cast Stone monoliths pertechnetate.
Development of monolithic pixel detector with SOI technology for the ILC vertex detector
Yamada, M.; Ono, S.; Tsuboyama, T.; Arai, Y.; Haba, J.; Ikegami, Y.; Kurachi, I.; Togawa, M.; Mori, T.; Aoyagi, W.; Endo, S.; Hara, K.; Honda, S.; Sekigawa, D.
2018-01-01
We have been developing a monolithic pixel sensor for the International Linear Collider (ILC) vertex detector with the 0.2 μm FD-SOI CMOS process by LAPIS Semiconductor Co., Ltd. We aim to achieve a 3 μm single-point resolution required for the ILC with a 20×20 μm2 pixel. Beam bunch crossing at the ILC occurs every 554 ns in 1-msec-long bunch trains with an interval of 200 ms. Each pixel must record the charge and time stamp of a hit to identify a collision bunch for event reconstruction. Necessary functions include the amplifier, comparator, shift register, analog memory and time stamp implementation in each pixel, and column ADC and Zero-suppression logic on the chip. We tested the first prototype sensor, SOFIST ver.1, with a 120 GeV proton beam at the Fermilab Test Beam Facility in January 2017. SOFIST ver.1 has a charge sensitive amplifier and two analog memories in each pixel, and an 8-bit Wilkinson-type ADC is implemented for each column on the chip. We measured the residual of the hit position to the reconstructed track. The standard deviation of the residual distribution fitted by a Gaussian is better than 3 μm.
Front-end receiver electronics for high-frequency monolithic CMUT-on-CMOS imaging arrays.
Gurun, Gokce; Hasler, Paul; Degertekin, F
2011-08-01
This paper describes the design of CMOS receiver electronics for monolithic integration with capacitive micromachined ultrasonic transducer (CMUT) arrays for highfrequency intravascular ultrasound imaging. A custom 8-inch (20-cm) wafer is fabricated in a 0.35-μm two-poly, four-metal CMOS process and then CMUT arrays are built on top of the application specific integrated circuits (ASICs) on the wafer. We discuss advantages of the single-chip CMUT-on-CMOS approach in terms of receive sensitivity and SNR. Low-noise and high-gain design of a transimpedance amplifier (TIA) optimized for a forward-looking volumetric-imaging CMUT array element is discussed as a challenging design example. Amplifier gain, bandwidth, dynamic range, and power consumption trade-offs are discussed in detail. With minimized parasitics provided by the CMUT-on-CMOS approach, the optimized TIA design achieves a 90 fA/√Hz input-referred current noise, which is less than the thermal-mechanical noise of the CMUT element. We show successful system operation with a pulseecho measurement. Transducer-noise-dominated detection in immersion is also demonstrated through output noise spectrum measurement of the integrated system at different CMUT bias voltages. A noise figure of 1.8 dB is obtained in the designed CMUT bandwidth of 10 to 20 MHz.
Development of high-throughput analysis system using highly-functional organic polymer monoliths
International Nuclear Information System (INIS)
Umemura, Tomonari; Kojima, Norihisa; Ueki, Yuji
2008-01-01
The growing demand for high-throughput analysis in the current competitive life sciences and industries has promoted the development of high-speed HPLC techniques and tools. As one of such tools, monolithic columns have attracted increasing attention and interest in the last decade due to the low flow-resistance and excellent mass transfer, allowing for rapid separations and reactions at high flow rates with minimal loss of column efficiency. Monolithic materials are classified into two main groups: silica- and organic polymer-based monoliths, each with their own advantages and disadvantages. Organic polymer monoliths have several distinct advantages in life-science research, including wide pH stability, less irreversible adsorption, facile preparation and modification. Thus, we have so far tried to develop organic polymer monoliths for various chemical operations, such as separation, extraction, preconcentration, and reaction. In the present paper, recent progress in the development of organic polymer monoliths is discussed. Especially, the procedure for the preparation of methacrylate-based monoliths with various functional groups is described, where the influence of different compositional and processing parameters on the monolithic structure is also addressed. Furthermore, the performance of the produced monoliths is demonstrated through the results for (1) rapid separations of alklybenzenes at high flow rates, (2) flow-through enzymatic digestion of cytochrome c on a trypsin-immobilized monolithic column, and (3) separation of the tryptic digest on a reversed-phase monolithic column. The flexibility and versatility of organic polymer monoliths will be beneficial for further enhancing analytical performance, and will open the way for new applications and opportunities both in scientific and industrial research. (author)
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.
A poly(vinyl alcohol)/sodium alginate blend monolith with nanoscale porous structure.
Sun, Xiaoxia; Uyama, Hiroshi
2013-10-04
A stimuli-responsive poly(vinyl alcohol) (PVA)/sodium alginate (SA) blend monolith with nanoscale porous (mesoporous) structure is successfully fabricated by thermally impacted non-solvent induced phase separation (TINIPS) method. The PVA/SA blend monolith with different SA contents is conveniently fabricated in an aqueous methanol without any templates. The solvent suitable for the fabrication of the present blend monolith by TINIPS is different with that of the PVA monolith. The nanostructural control of the blend monolith is readily achieved by optimizing the fabrication conditions. Brunauer Emmett Teller measurement shows that the obtained blend monolith has a large surface area. Pore size distribution plot for the blend monolith obtained by the non-local density functional theory method reveals the existence of the nanoscale porous structure. Fourier transform infrared analysis reveals the strong interactions between PVA and SA. The pH-responsive property of the blend monolith is investigated on the basis of swelling ratio in different pH solutions. The present blend monolith of biocompatible and biodegradable PVA and SA with nanoscale porous structure has large potential for applications in biomedical and environmental fields.
Study of complete interconnect reliability for a GaAs MMIC power amplifier
Lin, Qian; Wu, Haifeng; Chen, Shan-ji; Jia, Guoqing; Jiang, Wei; Chen, Chao
2018-05-01
By combining the finite element analysis (FEA) and artificial neural network (ANN) technique, the complete prediction of interconnect reliability for a monolithic microwave integrated circuit (MMIC) power amplifier (PA) at the both of direct current (DC) and alternating current (AC) operation conditions is achieved effectively in this article. As a example, a MMIC PA is modelled to study the electromigration failure of interconnect. This is the first time to study the interconnect reliability for an MMIC PA at the conditions of DC and AC operation simultaneously. By training the data from FEA, a high accuracy ANN model for PA reliability is constructed. Then, basing on the reliability database which is obtained from the ANN model, it can give important guidance for improving the reliability design for IC.
Acoustic of monolithic dome structures
Directory of Open Access Journals (Sweden)
Mostafa Refat Ismail
2018-03-01
The interior of monolithic domes have perfect, concave shapes to ensure that sound travels through the dome and perfectly collected at different vocal points. These dome structures are utilized for domestic use because the scale allows the focal points to be positioned across daily life activities, thereby affecting the sonic comfort of the internal space. This study examines the various acoustic treatments and parametric configurations of monolithic dome sizes. A geometric relationship of acoustic treatment and dome radius is established to provide architects guidelines on the correct selection of absorption needed to maintain the acoustic comfort of these special spaces.
Media Presentation Synchronisation for Non-monolithic Rendering Architectures
I. Vaishnavi (Ishan); D.C.A. Bulterman (Dick); P.S. Cesar Garcia (Pablo Santiago); B. Gao (Bo)
2007-01-01
htmlabstractNon-monolithic renderers are physically distributed media playback engines. Non-monolithic renderers may use a number of different underlying network connection types to transmit media items belonging to a presentation. There is therefore a need for a media based and inter-network- type
Monolithic integration of micromachined sensors and CMOS circuits based on SOI technologies
International Nuclear Information System (INIS)
Yu Xiaomei; Tang Yaquan; Zhang Haitao
2008-01-01
This note presents a novel way to monolithically integrate micro-cantilever sensors and signal conditioning circuits by combining SOI CMOS and SOI micromachining technologies. In order to improve the sensor performance and reduce the system volume, an integrated sensor system composed of a piezoresistive cantilever array, a temperature-compensation current reference, a digitally controlled multiplexer and an instrument amplifier is designed and finally fabricated. A post-SOI CMOS process is developed to realize the integrated sensor system which is based on a standard CMOS process with one more mask to define the cantilever structure at the end of the process. Measurements on the finished SOI CMOS devices and circuits show that the integration process has good compatibility both for the cantilever sensors and for the CMOS circuits, and the SOI CMOS integration process can decrease about 25% sequences compared with the bulk silicon CMOS process. (note)
Edge chipping and flexural resistance of monolithic ceramics☆
Zhang, Yu; Lee, James J.-W.; Srikanth, Ramanathan; Lawn, Brian R.
2014-01-01
Objective Test the hypothesis that monolithic ceramics can be developed with combined esthetics and superior fracture resistance to circumvent processing and performance drawbacks of traditional all-ceramic crowns and fixed-dental-prostheses consisting of a hard and strong core with an esthetic porcelain veneer. Specifically, to demonstrate that monolithic prostheses can be produced with a much reduced susceptibility to fracture. Methods Protocols were applied for quantifying resistance to chipping as well as resistance to flexural failure in two classes of dental ceramic, microstructurally-modified zirconias and lithium disilicate glass–ceramics. A sharp indenter was used to induce chips near the edges of flat-layer specimens, and the results compared with predictions from a critical load equation. The critical loads required to produce cementation surface failure in monolithic specimens bonded to dentin were computed from established flexural strength relations and the predictions validated with experimental data. Results Monolithic zirconias have superior chipping and flexural fracture resistance relative to their veneered counterparts. While they have superior esthetics, glass–ceramics exhibit lower strength but higher chip fracture resistance relative to porcelain-veneered zirconias. Significance The study suggests a promising future for new and improved monolithic ceramic restorations, with combined durability and acceptable esthetics. PMID:24139756
International Nuclear Information System (INIS)
Harzawadi Hasim; Maslina Ibrahim; Nolida Yusop; Mohd Ashhar Khalid
2011-01-01
Most of our electronic equipment has buffer, thus this make buffer as one of importance in electronic gadget. This paper introduced Single Ended Input Differential Output (SEIDO) buffer to predict the bias at approximately 2.5 V. For this purpose, the input range between -1 mV to 4 V was implemented. The software used to cascade SEIDO buffer is called LTspice IV; an open source software developed by Linear Technology Incorporation. The component involve in this development was Operational Amplifier (OP AMP) AD826 from Analog Devices Incorporation, capacitor and resistor. Kirchhoffs Current Law and Kirchhoffs Voltage Law was applied to calculated voltage gain and biasing voltage. All design has been verified by LTspice IV. The result produced from simulation was between -0.3 V to 6.3 V with bias roughly at 2.5 V. These results prove that it was capable to drive Analog Digital Converter (ADC) that can subsequently apply for Multichannel Analyzer (MCA). (author)
Low noise InP-based MMIC receivers for W-band
Leonard, Regis F.
1991-01-01
A program to develop a monolithic W-band low noise amplifier (a critical element in any W-band communications, sensors, or radar application) is described. Goals of the program include a completely monolithic low noise amplifier, less than a 3.5 dB noise figure, and a monolithic mixer suitable for integration with the LNA.
Basten, Christoph; Koch, Cathérine
2014-01-01
We examine mortgage pricing before and after Switzerland was the first country to activate the Counter-Cyclical Capital Buffer of Basel III. Observing multiple mortgage offers per request, we obtain three core findings. First, capitalconstrained and mortgage-specialized banks raise their rates relatively more. Second, risk-weighting schemes supposed to discriminate against more risky borrowers do not amplify the effect of higher capital requirements. Third, CCB-subjected banks and CCB-exempt ...
Creating deep soil core monoliths: Beyond the solum
Soil monoliths serve as useful teaching aids in the study of the Earth’s critical zone where rock, soil, water, air, and organisms interact. Typical monolith preparation has so far been confined to the 1 to 2-m depth of the solum. Critical ecosystem services provided by soils include materials from ...
FLUIDIZED BED STEAM REFORMER MONOLITH FORMATION
International Nuclear Information System (INIS)
Jantzen, C
2006-01-01
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 2 and steam, and nitrate/nitrite components, if any, to N 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 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 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
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.
Data quality objectives summary report for the 105-N monolith off-gas issue
International Nuclear Information System (INIS)
Pisarcik, D.J.
1997-01-01
The 105-N Basin hardware waste with radiation exposure rates high enough to make above-water handling and packaging impractical has been designated high exposure rate hardware (HERH) waste. This material, consisting primarily of irradiated reactor components, is packaged underwater for subsequent disposal as a grout-encapsulated solid monolith. The third HERH waste package that was created (Monolith No. 3) was not immediately removed from the basin because of administrative delays. During a routine facility walkdown, Monolith No. 3 was observed to be emitting bubbles. Mass spectroscopic analysis of a gas sample from Monolith No. 3 indicated that the gas was 85.2% hydrogen along with a trace of fission gases (stable isotopes of xenon). Gamma energy analysis of a gas sample from Monolith No. 3 also identified trace quantities of 85 Kr. The monolith off-gas Data Quality Objective (DQO) process concluded the following: Monolith No. 3 and similar monoliths can be safely transported following installation of spacers between the lids of the L3-181 transport cask to vent the hydrogen gas; The 85 Kr does not challenge personnel or environmental safety; Fumaroles in the surface of gassing monoliths renders them incompatible with Hanford Site Solid Waste Acceptance Criteria requirements unless placed in a qualified high integrity container overpack; and Gassing monoliths do meet Environmental Restoration Disposal Facility Waste Acceptance Criteria requirements. This DQO Summary Report is both an account of the Monolith Off-Gas DQO Process and a means of documenting the concurrence of each of the stakeholder organizations
A poly(vinyl alcohol)/sodium alginate blend monolith with nanoscale porous structure
Sun, Xiaoxia; Uyama, Hiroshi
2013-01-01
A stimuli-responsive poly(vinyl alcohol) (PVA)/sodium alginate (SA) blend monolith with nanoscale porous (mesoporous) structure is successfully fabricated by thermally impacted non-solvent induced phase separation (TINIPS) method. The PVA/SA blend monolith with different SA contents is conveniently fabricated in an aqueous methanol without any templates. The solvent suitable for the fabrication of the present blend monolith by TINIPS is different with that of the PVA monolith. The nanostructu...
Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders
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
Wang, Qiqin; Peng, Kun; Chen, Weijia; Cao, Zhen; Zhu, Peijie; Zhao, Yumei; Wang, Yuqiang; Zhou, Haibo; Jiang, Zhengjin
2017-01-06
This study described a simple synthetic methodology for preparing biomembrane mimicking monolithic column. The suggested approach not only simplifies the preparation procedure but also improves the stability of double chain phosphatidylcholine (PC) functionalized monolithic column. The physicochemical properties of the optimized monolithic column were characterized by scanning electron microscopy, energy-dispersive X-ray spectrometry, and nano-LC. Satisfactory column permeability, efficiency, stability and reproducibility were obtained on this double chain PC functionalized monolithic column. It is worth noting that the resulting polymeric monolith exhibits great potential as a useful alternative of commercial immobilized artificial membrane (IAM) columns for in vitro predication of drug-membrane interactions. Furthermore, the comparative study of both double chain and single chain PC functionalized monoliths indicates that the presence or absence of glycerol backbone and the number of acyl chains are not decisive for the predictive ability of IAM monoliths on drug-membrane interactions. This novel PC functionalized monolithic column also exhibited good selectivity for a protein mixture and a set of pharmaceutical compounds. Copyright © 2016 Elsevier B.V. All rights reserved.
Highly-stable monolithic femtosecond Yb-fiber laser system based on photonic crystal fibers
DEFF Research Database (Denmark)
Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry
2010-01-01
in the oscillator cavity for dispersion balancing and nonlinear optical limiting, and another one is used for low nonlinearity final pulse recompression. The chirped-pulse amplification and recompression of the 232-fs, 45-pJ/pulse oscillator output yields a final direct fiber-end delivery of 7.3-nJ energy pulses......A self-starting, passively stabilized, monolithic all polarizationmaintaining femtosecond Yb-fiber master oscillator / power amplifier with very high operational and environmental stability is demonstrated. The system is based on the use of two different photonic crystal fibers. One is used...... of around 297 fs duration. Our laser shows exceptional stability. No Q-switched modelocking events were detected during 4-days long observation. An average fluctuation of only 7.85 · 10−4 over the mean output power was determined as a result of more than 6-hours long measurement. The laser is stable towards...
Monolithic multinozzle emitters for nanoelectrospray mass spectrometry
Wang, Daojing [Daly City, CA; Yang, Peidong [Kensington, CA; Kim, Woong [Seoul, KR; Fan, Rong [Pasadena, CA
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.
Decomposition of monolithic web application to microservices
Zaymus, Mikulas
2017-01-01
Solteq Oyj has an internal Wellbeing project for massage reservations. The task of this thesis was to transform the monolithic architecture of this application to microservices. The thesis starts with a detailed comparison between microservices and monolithic application. It points out the benefits and disadvantages microservice architecture can bring to the project. Next, it describes the theory and possible strategies that can be used in the process of decomposition of an existing monoli...
Zhang, Zhenbin; Yan, Xiaojing; Sun, Liangliang; Zhu, Guijie; Dovichi, Norman J
2015-04-21
A detachable sulfonate-silica hybrid strong cation-exchange monolith was synthesized in a fused silica capillary, and used for solid phase extraction with online pH gradient elution during capillary zone electrophoresis-tandem mass spectrometry (CZE-MS/MS) proteomic analysis. Tryptic digests were prepared in 50 mM formic acid and loaded onto the strong cation-exchange monolith. Fractions were eluted using a series of buffers with lower concentration but higher pH values than the 50 mM formic acid background electrolyte. This combination of elution and background electrolytes results in both sample stacking and formation of a dynamic pH junction and allows use of relatively large elution buffer volumes while maintaining reasonable peak efficiency and resolution. A series of five pH bumps were applied to elute E. coli tryptic peptides from the monolith, followed by analysis using CZE coupled to an LTQ-Orbitrap Velos mass spectrometer; 799 protein groups and 3381 peptides were identified from 50 ng of the digest in a 2.5 h analysis, which approaches the identification rate for this organism that was obtained with an Orbitrap Fusion. We attribute the improved numbers of peptide and protein identifications to the efficient fractionation by the online pH gradient elution, which decreased the complexity of the sample in each elution step and improved the signal intensity of low abundance peptides. We also performed a comparative analysis using a nanoACQUITY UltraPerformance LCH system. Similar numbers of protein and peptide identifications were produced by the two methods. Protein identifications showed significant overlap between the two methods, whereas peptide identifications were complementary.
Fracture-resistant monolithic dental crowns.
Zhang, Yu; Mai, Zhisong; Barani, Amir; Bush, Mark; Lawn, Brian
2016-03-01
To quantify the splitting resistance of monolithic zirconia, lithium disilicate and nanoparticle-composite dental crowns. Fracture experiments were conducted on anatomically-correct monolithic crown structures cemented to standard dental composite dies, by axial loading of a hard sphere placed between the cusps. The structures were observed in situ during fracture testing, and critical loads to split the structures were measured. Extended finite element modeling (XFEM), with provision for step-by-step extension of embedded cracks, was employed to simulate full failure evolution. Experimental measurements and XFEM predictions were self-consistent within data scatter. In conjunction with a fracture mechanics equation for critical splitting load, the data were used to predict load-sustaining capacity for crowns on actual dentin substrates and for loading with a sphere of different size. Stages of crack propagation within the crown and support substrate were quantified. Zirconia crowns showed the highest fracture loads, lithium disilicate intermediate, and dental nanocomposite lowest. Dental nanocomposite crowns have comparable fracture resistance to natural enamel. The results confirm that monolithic crowns are able to sustain high bite forces. The analysis indicates what material and geometrical properties are important in optimizing crown performance and longevity. Copyright © 2015 Academy of Dental Materials. All rights reserved.
Agglomerated polymer monoliths with bimetallic nano-particles as flow-through micro-reactors
International Nuclear Information System (INIS)
Floris, P.; Twamley, B.; Nesterenko, P.N.; Paull, B.; Connolly, D.
2012-01-01
Polymer monoliths in capillary format have been prepared as solid supports for the immobilisation of platinum/palladium bimetallic nano-flowers. Optimum surface coverage of nano-flowers was realised by photografting the monoliths with vinyl azlactone followed by amination with ethylenediamine prior to nano-particle immobilisation. Field emission SEM imaging was used as a characterisation tool for evaluating nano-particle coverage, together with BET surface area analysis to probe the effect of nano-particle immobilisation upon monolith morphology. Ion exchange chromatography was also used to confirm the nature of the covalent attachment of nano-flowers on the monolithic surface. In addition, EDX and ICP analyses were used to quantify platinum and palladium on modified polymer monoliths. Finally the catalytic properties of immobilised bimetallic Pd/Pt nano-flowers were evaluated in flow-through mode, exploiting the porous interconnected flow-paths present in the prepared monoliths (pore diameter ∼ 1-2 μm). Specifically, the reduction of Fe (III) to Fe (II) and the oxidation of NADH to NAD+ were selected as model redox reactions. The use of a porous polymer monolith as an immobilisation substrate (rather than aminated micro-spheres) eliminated the need for a centrifugation step after the reaction. (author)
Bahrenburg, Sven; Karow, Anne R; Garidel, Patrick
2015-04-01
Protein therapeutics, including monoclonal antibodies (mAbs), have significant buffering capacity, particularly at concentrations>50 mg/mL. This report addresses pH-related issues critical to adoption of self-buffered monoclonal antibody formulations. We evaluated solution conditions with protein concentrations ranging from 50 to 250 mg/mL. Samples were both buffer-free and conventionally buffered with citrate. Samples were non-isotonic or adjusted for isotonicity with NaCl or trehalose. Studies included accelerated temperature stability tests, shaking stability studies, and pH changes in infusion media as protein concentrate is added. We present averaged buffering slopes of capacity that can be applied to any mAb and present a general method for calculating buffering capacity of buffer-free, highly concentrated antibody liquid formulations. In temperature stability tests, neither buffer-free nor conventionally buffered solution conditions showed significant pH changes. Conventionally buffered solutions showed significantly higher opalescence than buffer-free ones. In general, buffer-free solution conditions showed less aggregation than conventionally buffered solutions. Shaking stability tests showed no differences between buffer-free and conventionally buffered solutions. "In-use" preparation experiments showed that pH in infusion bag medium can rapidly approximate that of self-buffered protein concentrate as concentrate is added. In summary, the buffer capacity of proteins can be predicted and buffer-free therapeutic antibody preparations provide a viable alternative to conventionally buffered solutions. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Liu, Jiyang; Wang, Xiaohui; Wang, Tianshu; Li, Dan; Xi, Fengna; Wang, Jin; Wang, Erkang
2014-11-26
Biological modification of monolithic and porous 3D graphene is of great significance for extending its application in fabricating highly sensitive biosensors. The present work reports on the first biofunctionalization of monolithic and freestanding 3D graphene foam for one-step preparation of reagentless enzymatic biosensors by controllable chitosan (CS) electrodeposition technology. Using a homogeneous three-component electrodeposition solution containing a ferrocene (Fc) grafted CS hybrid (Fc-CS), glucose oxidase (GOD), and single-walled carbon nanotubes (SWNTs), a homogeneous biocomposite film of Fc-CS/SWNTs/GOD was immobilized on the surface of 3D graphene foam by one-step electrodeposition. The Fc groups grafted on chitosan can be stably immobilized on the 3D graphene surface and keep their original electrochemical activity. The SWNTs doped into the Fc-CS matrix act as a nanowire to facilitate electron transfer and improve the conductivity of the biocomposite film. Combined with the extraordinary properties of 3D graphene foam including large active surface area, high conductivity, and fast mass transport dynamics, the 3D graphene based enzymatic biosensor achieved a large linear range (5.0 μM to 19.8 mM), a low detection limit (1.2 μM), and rapid response (reaching the 95% steady-state response within 8 s) for reagentless detection of glucose in the phosphate buffer solution.
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.
Immobilisation of shredded soft waste in cement monolith
International Nuclear Information System (INIS)
Brown, D.J.; Dalton, M.J.; Smith, D.L.
1983-04-01
A grouting process for the immobilisation of shredded contaminated laboratory waste in a cement monolith is being developed at the Atomic Energy Establishment Winfrith. The objective is to produce a 'monolithic' type package which is acceptable both for sea and land disposal. The work carried out on this project in the period April 1982 - March 1983 is summarised in this report. (author)
International Nuclear Information System (INIS)
Catalá-Icardo, M.; Torres-Cartas, S.; Meseguer-Lloret, S.; Gómez-Benito, C.; Carrasco-Correa, E.; Simó-Alfonso, E.F.; Ramis-Ramos, G.; Herrero-Martínez, J.M.
2017-01-01
In this work, a method for the preparation and anchoring of polymeric monoliths in a polytetrafluoroethylene (PTFE) tubing as a column housing for microbore HPLC is described. In order to assure a covalent attachment of the monolith to the inner wall of the PTFE tube, a two-step procedure was developed. Two surface etching reagents, a commercial sodium naphthalene solution (Fluoroetch"®), or mixtures of H_2O_2 and H_2SO_4, were tried and compared. Then, the obtained hydroxyl groups on the PTFE surface were modified by methacryloylation. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy and scanning electron microscopy (SEM) confirmed the successful modification of the tubing wall and the stable anchorage of monolith to the wall, respectively. Special emphasis was also put on the reduction of the unwanted effects of shrinking of monolith during polymerization, by using an external proper mold and by selecting the adequate monomers in order to increase the flexibility of the polymer. Poly(glycidyl methacrylate-co-divinylbenzene) monoliths were in situ synthesized by thermal polymerization within the confines of surface-vinylized PTFE tubes. The modified PTFE tubing tightly held the monolith, and the monolithic column exhibited good pressure resistance up to 20 MPa. The column performance was also evaluated via the isocratic separation of a series of alkylbenzenes in the reversed-phase mode. The optimized monolithic columns gave plate heights ranged between 70 and 80 μm. The resulting monoliths were also satisfactorily applied to the separation of proteins. - Highlights: • Successful surface etching of PTFE inner wall tubing was done. • The modified PTFE support was next methacryloylated with GMA. • Organic polymeric monolith was in situ prepared in the functionalized PTFE tube. • The monolithic columns gave suitable pressure resistance and separation of proteins.
Energy Technology Data Exchange (ETDEWEB)
Catalá-Icardo, M., E-mail: mocaic@qim.upv.es [Research Institute for Integrated Management of Coastal Areas, Universitat Politècnica de València, Paranimf 1, 46730, Grao de Gandía, Valencia (Spain); Torres-Cartas, S.; Meseguer-Lloret, S.; Gómez-Benito, C. [Research Institute for Integrated Management of Coastal Areas, Universitat Politècnica de València, Paranimf 1, 46730, Grao de Gandía, Valencia (Spain); Carrasco-Correa, E.; Simó-Alfonso, E.F.; Ramis-Ramos, G. [Department of Analytical Chemistry, Universitat de València, Dr. Moliner 50, 46100, Burjassot, Valencia (Spain); Herrero-Martínez, J.M., E-mail: jmherrer@uv.es [Department of Analytical Chemistry, Universitat de València, Dr. Moliner 50, 46100, Burjassot, Valencia (Spain)
2017-04-01
In this work, a method for the preparation and anchoring of polymeric monoliths in a polytetrafluoroethylene (PTFE) tubing as a column housing for microbore HPLC is described. In order to assure a covalent attachment of the monolith to the inner wall of the PTFE tube, a two-step procedure was developed. Two surface etching reagents, a commercial sodium naphthalene solution (Fluoroetch{sup ®}), or mixtures of H{sub 2}O{sub 2} and H{sub 2}SO{sub 4}, were tried and compared. Then, the obtained hydroxyl groups on the PTFE surface were modified by methacryloylation. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy and scanning electron microscopy (SEM) confirmed the successful modification of the tubing wall and the stable anchorage of monolith to the wall, respectively. Special emphasis was also put on the reduction of the unwanted effects of shrinking of monolith during polymerization, by using an external proper mold and by selecting the adequate monomers in order to increase the flexibility of the polymer. Poly(glycidyl methacrylate-co-divinylbenzene) monoliths were in situ synthesized by thermal polymerization within the confines of surface-vinylized PTFE tubes. The modified PTFE tubing tightly held the monolith, and the monolithic column exhibited good pressure resistance up to 20 MPa. The column performance was also evaluated via the isocratic separation of a series of alkylbenzenes in the reversed-phase mode. The optimized monolithic columns gave plate heights ranged between 70 and 80 μm. The resulting monoliths were also satisfactorily applied to the separation of proteins. - Highlights: • Successful surface etching of PTFE inner wall tubing was done. • The modified PTFE support was next methacryloylated with GMA. • Organic polymeric monolith was in situ prepared in the functionalized PTFE tube. • The monolithic columns gave suitable pressure resistance and separation of proteins.
Increased thermal conductivity monolithic zeolite structures
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.
Brne, P; Lim, Y-P; Podgornik, A; Barut, M; Pihlar, B; Strancar, A
2009-03-27
Convective interaction media (CIM; BIA Separations) monoliths are attractive stationary phases for use in affinity chromatography because they enable fast affinity binding, which is a consequence of convectively enhanced mass transport. This work focuses on the development of novel CIM hydrazide (HZ) monoliths for the oriented immobilization of antibodies. Adipic acid dihydrazide (AADH) was covalently bound to CIM epoxy monoliths to gain hydrazide groups on the monolith surface. Two different antibodies were afterwards immobilized to hydrazide functionalized monolithic columns and prepared columns were tested for their selectivity. One column was further tested for the dynamic binding capacity.
FLUIDIZED BED STEAM REFORMER (FBSR) PRODUCT: MONOLITH FORMATION AND CHARACTERIZATION
International Nuclear Information System (INIS)
Jantzen, C
2006-01-01
The most important requirement for Hanford's low activity waste (LAW) form for shallow land disposal is the chemical durability of the product. A secondary, but still essential specification, is the compressive strength of the material with regards to the strength of the material under shallow land disposal conditions, e.g. the weight of soil overburden and potential intrusion by future generations, because the term ''near-surface disposal'' indicates disposal in the uppermost portion, or approximately the top 30 meters, of the earth's surface. The THOR(reg s ign) Treatment Technologies (TTT) mineral waste form for LAW is granular in nature because it is formed by Fluidized Bed Steam Reforming (FBSR). As a granular product it has been shown to be as durable as Hanford's LAW glass during testing with ASTM C-1285-02 known as the Product Consistency Test (PCT) and with the Single Pass Flow Through Test (SPFT). Hanford Envelope A and Envelope C simulants both performed well during PCT and SPFT testing and during subsequent performance assessment modeling. This is partially due to the high aluminosilicate content of the mineral product which provides a natural aluminosilicate buffering mechanism that inhibits leaching and is known to occur in naturally occurring aluminosilicate mineral analogs. In order for the TTT Na-Al-Si (NAS) granular mineral product to meet the compressive strength requirements (ASTM C39) for a Hanford waste form, the granular product needs to be made into a monolith or disposed of in High Integrity Containers (HIC's). Additionally, the Hanford intruder scenario for disposal in the Immobilized Low Activity Waste (ILAW) trench is mitigated as there is reduced intruder exposure when a waste form is in a monolithic form. During the preliminary testing of a monolith binder for TTT's FBSR mineral product, four parameters were monitored: (1) waste loading (not optimized for each waste form tested); (2) density; (3) compressive strength; and (4
A Monolithically-Integrated μGC Chemical Sensor System
Directory of Open Access Journals (Sweden)
Davor Copic
2011-06-01
Full Text Available Gas chromatography (GC is used for organic and inorganic gas detection with a range of applications including screening for chemical warfare agents (CWA, breath analysis for diagnostics or law enforcement purposes, and air pollutants/indoor air quality monitoring of homes and commercial buildings. A field-portable, light weight, low power, rapid response, micro-gas chromatography (μGC system is essential for such applications. We describe the design, fabrication and packaging of mGC on monolithically-integrated Si dies, comprised of a preconcentrator (PC, μGC column, detector and coatings for each of these components. An important feature of our system is that the same mechanical micro resonator design is used for the PC and detector. We demonstrate system performance by detecting four different CWA simulants within 2 min. We present theoretical analyses for cost/power comparisons of monolithic versus hybrid μGC systems. We discuss thermal isolation in monolithic systems to improve overall performance. Our monolithically-integrated μGC, relative to its hybrid cousin, will afford equal or slightly lower cost, a footprint that is 1/2 to 1/3 the size and an improved resolution of 4 to 25%.
A novel photocatalytic monolith reactor for multiphase heterogeneous photocatalysis
Du, P.; Carneiro, J.T.; Moulijn, J.A.; Mul, Guido
2008-01-01
A novel reactor for multi-phase photocatalysis is presented, the so-called internally illuminated monolith reactor (IIMR). In the concept of the IIMR, side light emitting fibers are placed inside the channels of a ceramic monolith, equipped with a TiO2 photocatalyst coated on the wall of each
Monolithic JFET preamplifier for ionization chamber calorimeter
International Nuclear Information System (INIS)
Radeka, V.; Rescia, S.; Manfredi, P.F.; Speziali, V.
1990-10-01
A monolithic charge sensitive preamplifier using exclusively n-channel diffused JFETs has been designed and is now being fabricated by INTERFET Corp. by means of a dielectrically isolated process which allows preserving as much as possible the technology upon which discrete JFETs are based. A first prototype built by means of junction isolated process has been delivered. The characteristics of monolithically integrated JFETs compare favorably with discrete devices. First results of tests of a preamplifier which uses these devices are reported. 4 refs
Epitaxial grown InP quantum dots on a GaAs buffer realized on GaP/Si(001) templates
Energy Technology Data Exchange (ETDEWEB)
Hartwig, Walter; Wiesner, Michael; Koroknay, Elisabeth; Paul, Matthias; Jetter, Michael; Michler, Peter [Institut fuer Halbleiteroptik und Funktionelle Grenzflaechen und Research Center SCoPE, Universitaet Stuttgart, Allmandring 3, 70569 Stuttgart (Germany)
2013-07-01
The increasing necessity of higher computational capacity and security in the information technology requires originally technical solutions, which today's standard microelectronics, as their technical limits are close, can't provide anymore. One way out offers the integration of III-V semiconductor photonics with low-dimensional structures in current CMOS technology, enabling on-chip quantum optical applications, like quantum cryptography or quantum computing. Challenges in the heteroepitaxy of III-V semiconductors and silicon are the mismatches in material properties of the both systems. Defects, like dislocations and anti-phase domains (APDs), inhibit the monolithic integration of III-V semiconductor on Si. We present the growth of a thin GaAs buffer on CMOS-compatible oriented Si(001) by metal-organic vapor-phase epitaxy. To circumvent the forming APDs in the GaAs buffer a GaP on Si template (provided by NAsP{sub III/V} GmbH) was used. The dislocation density was then reduced by integrating several layers of InAs quantum dots in the GaAs buffer to bend the threading misfit dislocations. On top of this structure we grew InP quantum dots embedded in a Al{sub x}Ga{sub 1-x}InP composition and investigated the photoluminescence properties.
2012-01-24
... microwave ``monolithic integrated circuits'' power amplifiers that meet certain criteria with respect to... packaged microwave ``monolithic integrated circuits'' (MMIC) power amplifiers that meet certain criteria.... 110825537-2038-02] RIN 0694-AF38 Export and Reexport License Requirements for Certain Microwave and...
Tetsuya, Saito; Nauta, Bram
2008-01-01
To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a differential amplifier circuit 1;
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.
Fracture Strength of Aged Monolithic and Bilayer Zirconia-Based Crowns
Directory of Open Access Journals (Sweden)
Deborah Pacheco Lameira
2015-01-01
Full Text Available The purpose of this study was to evaluate the effect of design and surface finishing on fracture strength of yttria-tetragonal zirconia polycrystal (Y-TZP crowns in monolithic (1.5 mm thickness and bilayer (0.8 mm zirconia coping and 0.7 mm porcelain veneer configuration after artificial aging. Bovine incisors received crown preparation and Y-TZP crowns were manufactured using CAD/CAM technique, according to the following groups (n=10: Polished monolithic zirconia crowns (PM; Glazed monolithic zirconia crowns (GM; Bi-layer crowns (BL. Crowns were cemented with resin cement, submitted to artificial aging in a chewing simulator (2.5 million cycles/80 N/artificial saliva/37°C, and tested for fracture strength. Two remaining crowns referring to PM and GM groups were submitted to a chemical composition analysis to measure the level of yttrium after aging. One-way ANOVA and Tukey’s test (P=.05 indicated that monolithic zirconia crowns presented similar fracture strength (PM=3476.2 N ± 791.7; GM=3561.5 N ± 991.6, which was higher than bilayer crowns (2060.4 N ± 810.6. There was no difference in the yttrium content among the three surfaces evaluated in the monolithic crowns. Thus, monolithic zirconia crowns present higher fracture strength than bilayer veneered zirconia after artificial aging and surface finishing does not affect their fracture strength.
Single-frequency, fully integrated, miniature DPSS laser based on monolithic resonator
Dudzik, G.; Sotor, J.; Krzempek, K.; Soboń, G.; Abramski, K. M.
2014-02-01
We present a single frequency, stable, narrow linewidth, miniature laser sources operating at 532 nm (or 1064 nm) based on a monolithic resonators. Such resonators utilize birefringent filters formed by YVO4 beam displacer and KTP or YVO4 crystals to force single frequency operation at 532 nm or 1064 nm, respectively. In both configurations Nd:YVO4 gain crystal is used. The resonators dimensions are 1x1x10.5 mm3 and 1x1x8.5 mm3 for green and infrared configurations, respectively. Presented laser devices, with total dimensions of 40x52x120 mm3, are fully equipped with driving electronics, pump diode, optical and mechanical components. The highly integrated (36x15x65 mm3) low noise driving electronics with implemented digital PID controller was designed. It provides pump current and resonator temperature stability of ±30 μA@650 mA and ±0,003ºC, respectively. The laser parameters can be set and monitored via the USB interface by external application. The developed laser construction is universal. Hence, the other wavelengths can be obtained only by replacing the monolithic resonator. The optical output powers in single frequency regime was at the level of 42 mW@532 nm and 0.5 W@1064 nm with the long-term fluctuations of ±0.85 %. The linewidth and the passive frequency stability under the free running conditions were Δν < 100 kHz and 3ṡ10-9@1 s integration time, respectively. The total electrical power supply consumption of laser module was only 4 W. Presented compact, single frequency laser operating at 532 nm and 1064 nm may be used as an excellent source for laser vibrometry, interferometry or seed laser for fiber amplifiers.
Tannin-based monoliths from emulsion-templating
International Nuclear Information System (INIS)
Szczurek, A.; Martinez de Yuso, A.; Fierro, V.; Pizzi, A.; Celzard, A.
2015-01-01
Highlights: • Efficient preparation procedures are presented for new and “green” tannin-based organic polyHIPEs. • Highest homogeneity and strength are obtained at an oil fraction near the close-packing value. • Structural and mechanical properties abruptly change above such critical value. - Abstract: Highly porous monoliths prepared by emulsion-templating, frequently called polymerised High Internal Phase Emulsions (polyHIPEs) in the literature, were prepared from “green” precursors such as Mimosa bark extract, sunflower oil and ethoxylated castor oil. Various oil fractions, ranging from 43 to 80 vol.%, were used and shown to have a dramatic impact on the resultant porous structure. A critical oil fraction around 70 vol.% was found to exist, close to the theoretical values of 64% and 74% for random and compact sphere packing, respectively, at which the properties of both emulsions and derived porous monoliths changed. Such change of behaviour was observed by many different techniques such as viscosity, electron microscopy, mercury intrusion, and mechanical studies. We show and explain why this critical oil fraction is the one leading to the strongest and most homogeneous porous monoliths
Fabrication of mesoporous polymer monolith: a template-free approach.
Okada, Keisuke; Nandi, Mahasweta; Maruyama, Jun; Oka, Tatsuya; Tsujimoto, Takashi; Kondoh, Katsuyoshi; Uyama, Hiroshi
2011-07-14
Mesoporous polyacrylonitrile (PAN) monolith has been fabricated by a template-free approach using the unique affinity of PAN towards a water/dimethyl sulfoxide (DMSO) mixture. A newly developed Thermally Induced Phase Separation Technique (TIPS) has been used to obtain the polymer monoliths and their microstructures have been controlled by optimizing the concentration and cooling temperature.
Keeports, David
2006-12-01
By definition, a high fidelity amplifier's instantaneous output voltage is directly proportional to its instantaneous input voltage. While high fidelity is generally valued in the amplification of recorded music, nonlinearity, also known as distortion, is desirable in the amplification of some musical instruments. In particular, guitar amplifiers exploit nonlinearity to increase both the harmonic content and sustain of a guitar's sound. I will discuss how both modifications in sound result from saturation of triode tubes and transistors. Additionally, I will describe the difference in the symmetry of saturation curves for transistors and tubes and the reason why tube guitar amplifiers are generally considered to be superior to solid-state amplifiers. Finally, I will discuss attempts to use solid-state electronics to replicate the sound of tube amplifiers.
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.
International Nuclear Information System (INIS)
Hong, Tingting; Yang, Xi; Xu, Yujing; Ji, Yibing
2016-01-01
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.
de Levie, Robert
1999-04-01
The proper functioning of enzymes in bodily fluids requires that the pH be maintained within rather narrow limits. The first line of defense against large pH fluctuations in such fluids is the passive control provided by the presence of pH buffers. The ability of pH buffers to stabilize the pH is indicated by the buffer value b introduced in 1922 by van Slyke. It is equally important for many enzymes that the redox potential is kept within a narrow range. In that case, stability of the potential is most readily achieved with a redox buffer. In this communication we define the redox buffer strength by analogy with acid-base buffer strength.
Shear bond strength of indirect composite material to monolithic zirconia.
Sari, Fatih; Secilmis, Asli; Simsek, Irfan; Ozsevik, Semih
2016-08-01
This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (α=.05). Bond strength was significantly lower in untreated specimens than in sandblasted specimens (Pcomposite material and monolithic zirconia.
Technology development for SOI monolithic pixel detectors
International Nuclear Information System (INIS)
Marczewski, J.; Domanski, K.; Grabiec, P.; Grodner, M.; Jaroszewicz, B.; Kociubinski, A.; Kucharski, K.; Tomaszewski, D.; Caccia, M.; Kucewicz, W.; Niemiec, H.
2006-01-01
A monolithic detector of ionizing radiation has been manufactured using silicon on insulator (SOI) wafers with a high-resistivity substrate. In our paper the integration of a standard 3 μm CMOS technology, originally designed for bulk devices, with fabrication of pixels in the bottom wafer of a SOI substrate is described. Both technological sequences have been merged minimizing thermal budget and providing suitable properties of all the technological layers. The achieved performance proves that fully depleted monolithic active pixel matrix might be a viable option for a wide spectrum of future applications
Monolithic Chip-Integrated Absorption Spectrometer from 3-5 microns, Phase I
National Aeronautics and Space Administration — A monolithically integrated indium phosphide (InP) to silicon-on-sapphire (SoS) platform is being proposed for a monolithic portable or handheld spectrometer between...
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.
Directory of Open Access Journals (Sweden)
Eswaran Uthirajoo
Full Text Available For the first time, a new circuit to extend the linear operation bandwidth of a LTE (Long Term Evolution power amplifier, while delivering a high efficiency is implemented in less than 1 mm2 chip area. The 950 µm × 900 µm monolithic microwave integrated circuit (MMIC power amplifier (PA is fabricated in a 2 µm InGaP/GaAs process. An on-chip analog pre-distorter (APD is designed to improve the linearity of the PA, up to 20 MHz channel bandwidth. Intended for 1.95 GHz Band 1 LTE application, the PA satisfies adjacent channel leakage ratio (ACLR and error vector magnitude (EVM specifications for a wide LTE channel bandwidth of 20 MHz at a linear output power of 28 dBm with corresponding power added efficiency (PAE of 52.3%. With a respective input and output return loss of 30 dB and 14 dB, the PA's power gain is measured to be 32.5 dB while exhibiting an unconditional stability characteristic from DC up to 5 GHz. The proposed APD technique serves to be a good solution to improve linearity of a PA without sacrificing other critical performance metrics.
Uthirajoo, Eswaran; Ramiah, Harikrishnan; Kanesan, Jeevan; Reza, Ahmed Wasif
2014-01-01
For the first time, a new circuit to extend the linear operation bandwidth of a LTE (Long Term Evolution) power amplifier, while delivering a high efficiency is implemented in less than 1 mm2 chip area. The 950 µm × 900 µm monolithic microwave integrated circuit (MMIC) power amplifier (PA) is fabricated in a 2 µm InGaP/GaAs process. An on-chip analog pre-distorter (APD) is designed to improve the linearity of the PA, up to 20 MHz channel bandwidth. Intended for 1.95 GHz Band 1 LTE application, the PA satisfies adjacent channel leakage ratio (ACLR) and error vector magnitude (EVM) specifications for a wide LTE channel bandwidth of 20 MHz at a linear output power of 28 dBm with corresponding power added efficiency (PAE) of 52.3%. With a respective input and output return loss of 30 dB and 14 dB, the PA's power gain is measured to be 32.5 dB while exhibiting an unconditional stability characteristic from DC up to 5 GHz. The proposed APD technique serves to be a good solution to improve linearity of a PA without sacrificing other critical performance metrics.
Uthirajoo, Eswaran; Ramiah, Harikrishnan; Kanesan, Jeevan; Reza, Ahmed Wasif
2014-01-01
For the first time, a new circuit to extend the linear operation bandwidth of a LTE (Long Term Evolution) power amplifier, while delivering a high efficiency is implemented in less than 1 mm2 chip area. The 950 µm × 900 µm monolithic microwave integrated circuit (MMIC) power amplifier (PA) is fabricated in a 2 µm InGaP/GaAs process. An on-chip analog pre-distorter (APD) is designed to improve the linearity of the PA, up to 20 MHz channel bandwidth. Intended for 1.95 GHz Band 1 LTE application, the PA satisfies adjacent channel leakage ratio (ACLR) and error vector magnitude (EVM) specifications for a wide LTE channel bandwidth of 20 MHz at a linear output power of 28 dBm with corresponding power added efficiency (PAE) of 52.3%. With a respective input and output return loss of 30 dB and 14 dB, the PA’s power gain is measured to be 32.5 dB while exhibiting an unconditional stability characteristic from DC up to 5 GHz. The proposed APD technique serves to be a good solution to improve linearity of a PA without sacrificing other critical performance metrics. PMID:25033049
DEFF Research Database (Denmark)
Liu, Mingquan; Tran, Tri Minh; Abbas Elhaj, Ahmed Awad
2017-01-01
monoliths, chosen based on the combination of meso- and macropores providing optimal percolative flow and accessible surface area, was synthesized in the presence of N-Fmoc and O-Et protected phosphoserine and phosphotyrosine to prepare molecularly imprinted monoliths with surface layers selective...... for phosphopeptides. These imprinted monoliths were characterized alongside nonimprinted monoliths by a variety of techniques and finally evaluated by liquid chromatography-mass spectrometry in the capillary format to assess their abilities to trap and release phosphorylated amino acids and peptides from partly...
DEFF Research Database (Denmark)
Turchinovich, Dmitry; Liu, Xiaomin; Lægsgaard, Jesper
2008-01-01
. The laser output is compressed in a spliced-on hollow-core PM photonic crystal fiber, thus providing direct end-of-the-fiber delivery of pulses of around 370 fs duration and 4 nJ energy with high mode quality. Tuning the pump power of the end amplifier of the laser allows for the control of output pulse......We report on an environmentally stable self-starting monolithic (i.e. without any free-space coupling) all-polarization-maintaining (PM) femtosecond Yb-fiber laser, stabilized against Q-switching by a narrow-band fiber Bragg grating and modelocked using a semiconductor saturable absorber mirror...
Frechet, Jean M. J. [Oakland, CA; Svec, Frantisek [Alameda, CA; Rohr, Thomas [Leiden, NL
2008-10-07
A microfluidic device preferably made of a thermoplastic polymer that includes a channel or a multiplicity of channels whose surfaces are modified by photografting. The device further includes a porous polymer monolith prepared via UV initiated polymerization within the channel, and functionalization of the pore surface of the monolith using photografting. Processes for making such surface modifications of thermoplastic polymers and porous polymer monoliths are set forth.
Oakley, Jennifer A; Shaw, Kirsty J; Docker, Peter T; Dyer, Charlotte E; Greenman, John; Greenway, Gillian M; Haswell, Stephen J
2009-06-07
A silica monolith used to support both electro-osmotic pumping (EOP) and the extraction/elution of DNA coupled with gel-supported reagents is described. The benefits of the combined EOP extraction/elution system were illustrated by combining DNA extraction and gene amplification using the polymerase chain reaction (PCR) process. All the reagents necessary for both processes were supported within pre-loaded gels that allow the reagents to be stored at 4 degrees C for up to four weeks in the microfluidic device. When carrying out an analysis the crude sample only needed to be hydrodynamically introduced into the device which was connected to an external computer controlled power supply via platinum wire electrodes. DNA was extracted with 65% efficiency after loading lysed cells onto a silica monolith. Ethanol contained within an agarose gel matrix was then used to wash unwanted debris away from the sample by EOP (100 V cm(-1) for 5 min). The retained DNA was subsequently eluted from the monolith by water contained in a second agarose gel, again by EOP using an electric field of 100 V cm(-1) for 5 min, and transferred into the PCR reagent containing gel. The eluted DNA in solution was successfully amplified by PCR, confirming that the concept of a complete self-contained microfluidic device could be realised for DNA sample clean up and amplification, using a simple pumping and on-chip reagent storage methodology.
Metal oxide nanorod arrays on monolithic substrates
Energy Technology Data Exchange (ETDEWEB)
Gao, Pu-Xian; Guo, Yanbing; Ren, Zheng
2018-01-02
A metal oxide nanorod array structure according to embodiments disclosed herein includes a monolithic substrate having a surface and multiple channels, an interface layer bonded to the surface of the substrate, and a metal oxide nanorod array coupled to the substrate surface via the interface layer. The metal oxide can include ceria, zinc oxide, tin oxide, alumina, zirconia, cobalt oxide, and gallium oxide. The substrate can include a glass substrate, a plastic substrate, a silicon substrate, a ceramic monolith, and a stainless steel monolith. The ceramic can include cordierite, alumina, tin oxide, and titania. The nanorod array structure can include a perovskite shell, such as a lanthanum-based transition metal oxide, or a metal oxide shell, such as ceria, zinc oxide, tin oxide, alumina, zirconia, cobalt oxide, and gallium oxide, or a coating of metal particles, such as platinum, gold, palladium, rhodium, and ruthenium, over each metal oxide nanorod. Structures can be bonded to the surface of a substrate and resist erosion if exposed to high velocity flow rates.
Fine-grain concrete from mining waste for monolithic construction
Lesovik, R. V.; Ageeva, M. S.; Lesovik, G. A.; Sopin, D. M.; Kazlitina, O. V.; Mitrokhin, A. A.
2018-03-01
The technology of a monolithic construction is a well-established practice among most Russian real estate developers. The strong points of the technology are low cost of materials and lower demand for qualified workers. The monolithic construction uses various types of reinforced slabs and foamed concrete, since they are easy to use and highly durable; they also need practically no additional treatment.
CHARACTERIZATION OF MONOLITHIC FUEL FOIL PROPERTIES AND BOND STRENGTH
International Nuclear Information System (INIS)
D E Burkes; D D Keiser; D M Wachs; J S Larson; M D Chapple
2007-01-01
Understanding fuel foil mechanical properties, and fuel/cladding bond quality and strength in monolithic plates is an important area of investigation and quantification. Specifically, what constitutes an acceptable monolithic fuel--cladding bond, how are the properties of the bond measured and determined, and what is the impact of fabrication process or change in parameters on the level of bonding? Currently, non-bond areas are quantified employing ultrasonic determinations that are challenging to interpret and understand in terms of irradiation impact. Thus, determining mechanical properties of the fuel foil and what constitutes fuel/cladding non-bonds is essential to successful qualification of monolithic fuel plates. Capabilities and tests related to determination of these properties have been implemented at the INL and are discussed, along with preliminary results
Karenga, Samuel; El Rassi, Ziad
2011-04-01
Monolithic capillaries made of two adjoining segments each filled with a different monolith were introduced for the control and manipulation of the electroosmotic flow (EOF), retention and selectivity in reversed phase-capillary electrochromatography (RP-CEC). These columns were called segmented monolithic columns (SMCs) where one segment was filled with a naphthyl methacrylate monolith (NMM) to provide hydrophobic and π-interactions, while the other segment was filled with an octadecyl acrylate monolith (ODM) to provide solely hydrophobic interaction. The ODM segment not only provided hydrophobic interactions but also functioned as the EOF accelerator segment. The average EOF of the SMC increased linearly with increasing the fractional length of the ODM segment. The neutral SMC provided a convenient way for tuning EOF, selectivity and retention in the absence of annoying electrostatic interactions and irreversible solute adsorption. The SMCs allowed the separation of a wide range of neutral solutes including polycyclic aromatic hydrocarbons (PAHs) that are difficult to separate using conventional alkyl-bonded stationary phases. In all cases, the k' of a given solute was a linear function of the fractional length of the ODM or NMM segment in the SMCs, thus facilitating the tailoring of a given SMC to solve a given separation problem. At some ODM fractional length, the fabricated SMC allowed the separation of charged solutes such as peptides and proteins that could not otherwise be achieved on a monolithic column made from NMM as an isotropic stationary phase due to the lower EOF exhibited by this monolith. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Liu, Li-Hua; Yang, Cheng-Xiong; Yan, Xiu-Ping
2017-01-06
Covalent-organic frameworks (COFs) are a newfangled class of intriguing microporous materials. Considering their unique properties, COFs should be promising as packing materials for high performance liquid chromatography (HPLC). However, the irregular shape and sub-micrometer size of COFs synthesized via the traditional methods render the main obstacles for the application of COFs in HPLC. Herein, we report the preparation of methacrylate-bonded COF monolithic columns for HPLC to overcome the above obstacles. The prepared COF bonded monolithic columns not only show good homogeneity and permeability, but also give high column efficiency, good resolution and precision for HPLC separation of small molecules including polycyclic aromatic hydrocarbons, phenols, anilines, nonsteroidal anti-inflammatory drugs and benzothiophenes. Compared with the bare polymer monolithic column, the COF bonded monolithic columns show enhanced hydrophobic, π-π and hydrogen bond interactions in reverse phase HPLC. The results reveal the great potential of COF bonded monoliths for HPLC and COFs in separation sciences. Copyright © 2016 Elsevier B.V. All rights reserved.
Kato, T.; Kataoka, J.; Nakamori, T.; Kishimoto, A.; Yamamoto, S.; Sato, K.; Ishikawa, Y.; Yamamura, K.; Kawabata, N.; Ikeda, H.; Kamada, K.
2013-05-01
We report the development of a high spatial resolution tweezers-type coincidence gamma-ray camera for medical imaging. This application consists of large-area monolithic Multi-Pixel Photon Counters (MPPCs) and submillimeter pixelized scintillator matrices. The MPPC array has 4 × 4 channels with a three-side buttable, very compact package. For typical operational gain of 7.5 × 105 at + 20 °C, gain fluctuation over the entire MPPC device is only ± 5.6%, and dark count rates (as measured at the 1 p.e. level) amount to acrylic light guide measuring 1 mm thick, and with summing operational amplifiers that compile the signals into four position-encoded analog outputs being used for signal readout. Spatial resolution of 1.1 mm was achieved with the coincidence imaging system using a 22Na point source. These results suggest that the gamma-ray imagers offer excellent potential for applications in high spatial medical imaging.
DEFF Research Database (Denmark)
Cui, Xiaoti; Kær, Søren Knudsen
2018-01-01
Monolithic catalysts have received increasing attention for application in the small-scale steam methane reforming process. The radial heat transfer behaviors of monolith reformers were analyzed by two-dimensional computational fluid dynamic (CFD) modeling. A parameter study was conducted...... by a large number of simulations focusing on the thermal conductivity of the monolith substrate, washcoat layer, wall gap, radiation heat transfer and the geometric parameters (cell density, porosity and diameter of monolith). The effective radial thermal conductivity of the monolith structure, kr......,eff, showed good agreement with predictions made by the pseudo-continuous symmetric model. This influence of the radiation heat transfer is low for highly conductive monoliths. A simplified model has been developed to evaluate the importance of radiation for monolithic reformers under different conditions...
Burke, Jeffrey M; Smela, Elisabeth
2012-03-01
A new method of surface modification is described for enabling the in situ formation of homogenous porous polymer monoliths (PPMs) within poly(dimethylsiloxane) (PDMS) microfluidic channels that uses 365 nm UV illumination for polymerization. Porous polymer monolith formation in PDMS can be challenging because PDMS readily absorbs the monomers and solvents, changing the final monolith morphology, and because PDMS absorbs oxygen, which inhibits free-radical polymerization. The new approach is based on sequentially absorbing a non-hydrogen-abstracting photoinitiator and the monomers methyl methacrylate and ethylene diacrylate within the walls of the microchannel, and then polymerizing the surface treatment polymer within the PDMS, entangled with it but not covalently bound. Four different monolith compositions were tested, all of which yielded monoliths that were securely anchored and could withstand pressures exceeding the bonding strength of PDMS (40 psi) without dislodging. One was a recipe that was optimized to give a larger average pore size, required for low back pressure. This monolith was used to concentrate and subsequently mechanical lyse B lymphocytes.
Affinity monolith chromatography: A review of principles and recent analytical applications
Pfaunmiller, Erika L.; Paulemond, Marie Laura; Dupper, Courtney M.; Hage, David S.
2012-01-01
Affinity monolith chromatography (AMC) is a type of liquid chromatography that uses a monolithic support and a biologically-related binding agent as a stationary phase. AMC is a powerful method for the selective separation, analysis or studies of specific target compounds in a sample. This review discusses the basic principles of AMC and recent developments or applications of this method, with particular emphasis being given to work that has appeared in the last five years. Various materials that have been used to prepare columns for AMC are examined, including organic monoliths, silica monoliths, agarose monoliths and cryogels. These supports have been used in AMC for formats that have ranged from traditional columns to disks, microcolumns and capillaries. Many binding agents have also been employed in AMC, such as antibodies, enzymes, proteins, lectins, immobilized metal-ions and dyes. Some applications that have been reported with these binding agents in AMC are bioaffinity chromatography, immunoaffinity chromatography or immunoextraction, immobilized metal-ion affinity chromatography, dye-ligand affinity chromatography, chiral separations and biointeraction studies. Examples are presented from fields that include analytical chemistry, pharmaceutical analysis, clinical testing and biotechnology. Current trends and possible future directions in AMC are also discussed. PMID:23187827
Preparation of porous polymer monoliths featuring enhanced surface coverage with gold nanoparticles
Lv, Yongqin
2012-10-01
A new approach to the preparation of porous polymer monoliths with enhanced coverage of pore surface with gold nanoparticles has been developed. First, a generic poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith was reacted with cystamine followed by the cleavage of its disulfide bonds with tris(2-carboxylethyl)phosphine, which liberated the desired thiol groups. Dispersions of gold nanoparticles with sizes varying from 5 to 40. nm were then pumped through the functionalized monoliths. The materials were then analyzed using both energy dispersive X-ray spectroscopy and thermogravimetric analysis. We found that the quantity of attached gold was dependent on the size of nanoparticles, with the maximum attachment of more than 60. wt% being achieved with 40. nm nanoparticles. Scanning electron micrographs of the cross sections of all the monoliths revealed the formation of a non-aggregated, homogenous monolayer of nanoparticles. The surface of the bound gold was functionalized with 1-octanethiol and 1-octadecanethiol, and these monolithic columns were used successfully for the separations of proteins in reversed phase mode. The best separations were obtained using monoliths modified with 15, 20, and 30. nm nanoparticles since these sizes produced the most dense coverage of pore surface with gold. © 2012 Elsevier B.V.
Microwaves integrated circuits: hybrids and monolithics - fabrication technology
International Nuclear Information System (INIS)
Cunha Pinto, J.K. da
1983-01-01
Several types of microwave integrated circuits are presented together with comments about technologies and fabrication processes; advantages and disadvantages in their utilization are analysed. Basic structures, propagation modes, materials used and major steps in the construction of hybrid thin film and monolithic microwave integrated circuits are described. Important technological applications are revised and main activities of the microelectronics lab. of the University of Sao Paulo (Brazil) in the field of hybrid and monolithic microwave integrated circuits are summarized. (C.L.B.) [pt
Wu, L.; Liu, S.; Yang, Yingjie
2016-01-01
Traditional integer order buffer operator is extended to fractional order buffer operator, the corresponding relationship between the weakening buffer operator and the strengthening buffer operator is revealed. Fractional order buffer operator not only can generalize the weakening buffer operator and the strengthening buffer operator, but also realize tiny adjustment of buffer effect. The effectiveness of GM(1,1) with the fractional order buffer operator is validated by six cases.
Energy Technology Data Exchange (ETDEWEB)
Wang, Huiqi; Li, Zheng [College of Chemistry, Jilin University, Changchun 130012 (China); Niu, Qian [Jilin Entry-Exit Inspection and Quarantine Bureau, Changchun 130062 (China); Ma, Jiutong [College of Chemistry, Jilin University, Changchun 130012 (China); Jia, Qiong, E-mail: jiaqiong@jlu.edu.cn [College of Chemistry, Jilin University, Changchun 130012 (China)
2015-10-30
Graphical abstract: Poly(methacrylic acid-ethylene dimethacrylate) monolithic column embedded with zeolites was prepared and employed for the polymer monolith microextraction of colorants combined with HPLC. - Highlights: • Zeolite, as a kind of mesoporous material, was firstly combined with PMME. • Zeolite@poly(MAA-EDMA) monolith columns were prepared for the enrichment of colorants. • Zeolite@poly(MAA-EDMA) monolith columns demonstrated relatively high extraction capacity. - Abstract: A novel zeolite-modified poly(methacrylic acid-ethylenedimethacrylate) (zeolite@poly(MAA-EDMA)) monolithic column was prepared with the in situ polymerization method and employed in polymer monolith microextraction for the separation and preconcentration of synthetic colorants combined with high performance liquid chromatography. The polymer was characterized by scanning electronmicroscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermo-gravimetric analysis. Various parameters affecting the extraction efficiency were investigated and optimized. Under the optimum experimental conditions, we obtained acceptable linearities, low limits of detection, and good intra-day/inter-day relative standard deviations. The method was applied to the determination of synthetic colorants in lipsticks with recoveries ranged from 70.7% to 109.7%. Compared with conventional methacrylic acid-based monoliths, the developed monolith exhibited high enrichment capacity because of the introduction of zeolites into the preparation process. The extraction efficiency followed the order: zeolite@poly(MAA-EDMA) > poly(MAA-EDMA) > direct HPLC analysis.
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...
Cholesterol-imprinted macroporous monoliths: Preparation and characterization.
Stepanova, Mariia А; Kinziabulatova, Lilia R; Nikitina, Anna A; Korzhikova-Vlakh, Evgenia G; Tennikova, Tatiana B
2017-11-01
The development of sorbents for selective binding of cholesterol, which is a risk factor for cardiovascular disease, has a great importance for analytical science and medicine. In this work, two series of macroporous cholesterol-imprinted monolithic sorbents differing in the composition of functional monomers (methacrylic acid, butyl methacrylate, 2-hydroxyethyl methacrylate and ethylene dimethacrylate), amount of a template (4, 6 and 8 mol%) used for molecular imprinting, as well as mean pore size were synthesized by in situ free-radical process in stainless steel housing of 50 mm × 4.6 mm i.d. All prepared materials were characterized regarding to their hydrodynamic permeability and porous properties, as well as examined by BET and SEM methods. Imprinting factors, apparent dynamic dissociation constants, the maximum binding capacity, the number of theoretical plates and the height equivalent to a theoretical palate of MIP monoliths at different mobile phase flow rates were determined. The separation of a mixture of structural analogues, namely, cholesterol and prednisolone, was demonstrated. Additionally, the possibility of using the developed monoliths for cholesterol solid-phase extraction from simulated biological solution was shown. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Strength of normal sections of NPP composite monolithic constructions with ribbed reinforced panels
International Nuclear Information System (INIS)
Klyashitskij, V.I.; Kirillov, A.P.
1980-01-01
Strength characteristics and recommendations on designing composite-monolytic structures of NPP with ribbed reinforced panels are considered. Ribbed reinforced panel consists of a system of cross ribs joined with a comparatively thin (25 mm thick) plate. The investigations were carried on using models representing columns symmetrically reinforced with reinforced panels with a low percent of reinforcing. The monolithic structures consisting of ribbed reinforced panels and cast concrete for making monoliths as well as monolithic having analogous strength characteristics of extended and compressed zones have similar strengths. It is shown that calculation of supporting power of composite-monolithic structures is performed according to techniques developed for monolithic structures. Necessity of structural transverse fittings no longer arises in case of corresponding calculational substitution of stability of compressed parts of fittings. Supporting power of a structure decreases not more than by 10% in the presence of cracks in the reinforced panels of the compressed zone. Application of composite-monolithic structures during the construction of the Kursk, Smolensk and Chernobylskaya NPPs permitted to decrease labour content and reduce periods of accomplishment of these works which saves over 6 million roubles
Auto-Zero Differential Amplifier
Quilligan, Gerard T. (Inventor); Aslam, Shahid (Inventor)
2017-01-01
An autozero amplifier may include a window comparator network to monitor an output offset of a differential amplifier. The autozero amplifier may also include an integrator to receive a signal from a latched window comparator network, and send an adjustment signal back to the differential amplifier to reduce an offset of the differential amplifier.
High density fuels using dispersion and monolithic fuel
Energy Technology Data Exchange (ETDEWEB)
Gomes, Daniel S.; Silva, Antonio T.; Abe, Alfredo Y.; Muniz, Rafael O.R.; Giovedi, Claudia, E-mail: dsgomes@ipen.br, E-mail: teixeira@ipen.br, E-mail: alfredo@ctmsp.mar.mil.br, E-mail: rafael.orm@gmail.com, E-mail: claudia.giovedi@ctmsp.mar.mil.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Universidade de São Paulo (USP), SP (Brazil). Departamento de Engenharia Naval e Oceânica
2017-07-01
Fuel plates used in high-performance research reactors need to be converted to low-enrichment uranium fuel; the fuel option based on a monolithic formulation requires alloys to contain 6 - 10 wt% Mo. In this case, the fuel plates are composed of the metallic alloy U-10Mo surrounded by a thin zirconium layer encapsulated in aluminum cladding. This study reviewed the physical properties of monolithic forms. The constraints produced during the manufacturing process were analyzed and compared to those of dispersed fuel. The bonding process used for dispersion fuels differs from the techniques applied to foil bonding used for pure alloys. The quality of monolithic plates depends on the fabrication method, which usually involves hot isostatic pressing and the thermal annealing effect of residual stress, which degrades the uranium cubic phase. The preservation of the metastable phase has considerable influence on fuel performance. The physical properties of the foil fuel under irradiation are superior to those of aluminum-dispersed fuels. The fuel meat, using zirconium as the diffusion barrier, prevents the interaction layer from becoming excessively thick. The problem with dispersed fuel is breakaway swelling with a medium fission rate. It has been observed that the fuel dispersed in aluminum was minimized in monolithic forms. The pure alloys exhibited a suitable response from a rate at least twice as much as the fission rate of dispersions. The foils can support fissile material concentration combined with a reduced swelling rate. (author)
High density fuels using dispersion and monolithic fuel
International Nuclear Information System (INIS)
Gomes, Daniel S.; Silva, Antonio T.; Abe, Alfredo Y.; Muniz, Rafael O.R.; Giovedi, Claudia; Universidade de São Paulo
2017-01-01
Fuel plates used in high-performance research reactors need to be converted to low-enrichment uranium fuel; the fuel option based on a monolithic formulation requires alloys to contain 6 - 10 wt% Mo. In this case, the fuel plates are composed of the metallic alloy U-10Mo surrounded by a thin zirconium layer encapsulated in aluminum cladding. This study reviewed the physical properties of monolithic forms. The constraints produced during the manufacturing process were analyzed and compared to those of dispersed fuel. The bonding process used for dispersion fuels differs from the techniques applied to foil bonding used for pure alloys. The quality of monolithic plates depends on the fabrication method, which usually involves hot isostatic pressing and the thermal annealing effect of residual stress, which degrades the uranium cubic phase. The preservation of the metastable phase has considerable influence on fuel performance. The physical properties of the foil fuel under irradiation are superior to those of aluminum-dispersed fuels. The fuel meat, using zirconium as the diffusion barrier, prevents the interaction layer from becoming excessively thick. The problem with dispersed fuel is breakaway swelling with a medium fission rate. It has been observed that the fuel dispersed in aluminum was minimized in monolithic forms. The pure alloys exhibited a suitable response from a rate at least twice as much as the fission rate of dispersions. The foils can support fissile material concentration combined with a reduced swelling rate. (author)
Paladin Enterprises: Monolithic particle physics models global climate.
2002-01-01
Paladin Enterprises presents a monolithic particle model of the universe which will be used by them to build an economical fusion energy system. The model is an extension of the work done by James Clerk Maxwell. Essentially, gravity is unified with electro-magnetic forces and shown to be a product of a closed loop current system, i.e. a particle - monolithic or sub atomic. This discovery explains rapid global climate changes which are evident in the geological record and also provides an explanation for recent changes in the global climate.
Broadband EM Performance Characteristics of Single Square Loop FSS Embedded Monolithic Radome
Directory of Open Access Journals (Sweden)
Raveendranath U. Nair
2013-01-01
Full Text Available A monolithic half-wave radome panel, centrally loaded with aperture-type single square loop frequency selective surface (SSL-FSS, is proposed here for broadband airborne radome applications. Equivalent transmission line method in conjunction with equivalent circuit model (ECM is used for modeling the SSL-FSS embedded monolithic half-wave radome panel and evaluating radome performance parameters. The design parameters of the SSL-FSS are optimized at different angles of incidence such that the new radome wall configuration offers superior EM performance from L-band to X-band as compared to the conventional monolithic half-wave slab of identical material and thickness. The superior EM performance of SSL-FSS embedded monolithic radome wall makes it suitable for the design of normal incidence and streamlined airborne radomes.
International Nuclear Information System (INIS)
Han, Jiaxi; Du, Zhongjie; Zou, Wei; Li, Hangquan; Zhang, Chen
2014-01-01
Highlights: • Interface functionalized PGMA porous monolith was fabricated. • The adsorption capacity of Cu 2+ was 35.3 mg/g. • The effects of porous structure on the adsorption of Cu 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 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
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.
A THEORETICAL DISCUSSION OF THE ECONOMIC EFFECTS OF BUFFER STOCKS AND BUFFER FUNDS
Simmons, Phil
1988-01-01
It has been established that the absence of risk markets justifies market intervention in principle. The form of intervention that has been discussed most widely in the literature is the buffer stock. This paper points out that other forms of intervention, specifically buffer funds, are likely to perform better. The analysis shows that buffer funds are likely to outperform buffer stocks because they address market failure more directly. A sub-theme developed in this paper is that since buffer...
Photon-counting monolithic avalanche photodiode arrays for the super collider
International Nuclear Information System (INIS)
Ishaque, A.N.; Castleberry, D.E.; Rougeot, H.M.
1994-01-01
In fiber tracking, calorimetry, and other high energy and nuclear physics experiments, the need arises to detect an optical signal consisting of a few photons (in some cases a single photoelectron) with a detector insensitive to magnetic fields. Previous attempts to detect a single photoelectron have involved avalanche photodiodes (APDs) operated in the Geiger mode, the visible light photon counter, and a photomultiplier tube with an APD as the anode. In this paper it is demonstrated that silicon APDs, biased below the breakdown voltage, can be used to detect a signal of a few photons with conventional pulse counting circuitry at room temperature. Moderate cooling, it is further argued, could make it possible to detect a single photoelectron. Monolithic arrays of silicon avalanche photodiodes fabricated by Radiation Monitoring Devices, Inc. (RMD) were evaluated for possible use in the Super Collider detector systems. Measurements on 3 element x 3 element (2 mm pitch) APD arrays, using pulse counting circuitry with a charge sensitive amplifier (CSA) and a Gaussian filter, are reported and found to conform to a simple noise model. The model is used to obtain the optimal operating point. Experimental results are described in Section II, modeling results in Section III, and the conclusions are summarized in Section IV
Portable musical instrument amplifier
Christian, David E.
1990-07-24
The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.
Monolithic optoelectronic integrated broadband optical receiver with graphene photodetectors
Directory of Open Access Journals (Sweden)
Cheng Chuantong
2017-07-01
Full Text Available Optical receivers with potentially high operation bandwidth and low cost have received considerable interest due to rapidly growing data traffic and potential Tb/s optical interconnect requirements. Experimental realization of 65 GHz optical signal detection and 262 GHz intrinsic operation speed reveals the significance role of graphene photodetectors (PDs in optical interconnect domains. In this work, a novel complementary metal oxide semiconductor post-backend process has been developed for integrating graphene PDs onto silicon integrated circuit chips. A prototype monolithic optoelectronic integrated optical receiver has been successfully demonstrated for the first time. Moreover, this is a firstly reported broadband optical receiver benefiting from natural broadband light absorption features of graphene material. This work is a perfect exhibition of the concept of monolithic optoelectronic integration and will pave way to monolithically integrated graphene optoelectronic devices with silicon ICs for three-dimensional optoelectronic integrated circuit chips.
Monolithic optoelectronic integrated broadband optical receiver with graphene photodetectors
Cheng, Chuantong; Huang, Beiju; Mao, Xurui; Zhang, Zanyun; Zhang, Zan; Geng, Zhaoxin; Xue, Ping; Chen, Hongda
2017-07-01
Optical receivers with potentially high operation bandwidth and low cost have received considerable interest due to rapidly growing data traffic and potential Tb/s optical interconnect requirements. Experimental realization of 65 GHz optical signal detection and 262 GHz intrinsic operation speed reveals the significance role of graphene photodetectors (PDs) in optical interconnect domains. In this work, a novel complementary metal oxide semiconductor post-backend process has been developed for integrating graphene PDs onto silicon integrated circuit chips. A prototype monolithic optoelectronic integrated optical receiver has been successfully demonstrated for the first time. Moreover, this is a firstly reported broadband optical receiver benefiting from natural broadband light absorption features of graphene material. This work is a perfect exhibition of the concept of monolithic optoelectronic integration and will pave way to monolithically integrated graphene optoelectronic devices with silicon ICs for three-dimensional optoelectronic integrated circuit chips.
Dual jaw treatment of edentulism using implant-supported monolithic zirconia fixed prostheses.
Altarawneh, Sandra; Limmer, Bryan; Reside, Glenn J; Cooper, Lyndon
2015-01-01
This case report describes restoration of the edentulous maxilla and mandible with implant supported fixed prostheses using monolithic zirconia, where the incisal edges and occluding surfaces were made of monolithic zirconia. Edentulism is a debilitating condition that can be treated with either a removable or fixed dental prosthesis. The most common type of implant-supported fixed prosthesis is the metal acrylic (hybrid), with ceramo-metal prostheses being used less commonly in complete edentulism. However, both of these prostheses designs are associated with reported complications of screw loosening or fracture and chipping of acrylic resin and porcelain. Monolithic zirconia implant-supported fixed prostheses have the potential for reduction of such complications. In this case, the CAD/CAM concept was utilized in fabrication of maxillary and mandibular screw-retained implant-supported fixed prostheses using monolithic zirconia. Proper treatment planning and execution coupled with utilizing advanced technologies contributes to highly esthetic results. However, long-term studies are required to guarantee a satisfactory long-term outcome of this modality of treatment. This case report describes the clinical and technical procedures involved in fabrication of maxillary and mandibular implant-supported fixed prostheses using monolithic zirconia as a treatment of edentulism, and proposes the possible advantages associated with using monolithic zirconia in eliminating dissimilar interfaces in such prostheses that are accountable for the most commonly occurring technical complication for these prostheses being chipping and fracture of the veneering material. © 2015 Wiley Periodicals, Inc.
Patterson, Richard L.; Elbuluk, Malik; Hammoud, Ahmad; VanKeuls, Frederick W.
2009-01-01
This report discusses the performance of silicon germanium, wideband gain amplifiers under extreme temperatures. The investigated devices include Texas Instruments THS4304-SP and THS4302 amplifiers. Both chips are manufactured using the BiCom3 process based on silicon germanium technology along with silicon-on-insulator (SOI) buried oxide layers. The THS4304-SP device was chosen because it is a Class V radiation-tolerant (150 kRad, TID silicon), voltage-feedback operational amplifier designed for use in high-speed analog signal applications and is very desirable for NASA missions. It operates with a single 5 V power supply [1]. It comes in a 10-pin ceramic flatpack package, and it provides balanced inputs, low offset voltage and offset current, and high common mode rejection ratio. The fixed-gain THS4302 chip, which comes in a 16-pin leadless package, offers high bandwidth, high slew rate, low noise, and low distortion [2]. Such features have made the amplifier useful in a number of applications such as wideband signal processing, wireless transceivers, intermediate frequency (IF) amplifier, analog-to-digital converter (ADC) preamplifier, digital-to-analog converter (DAC) output buffer, measurement instrumentation, and medical and industrial imaging.
COMBINATIONS OF BUFFER-STOCKS AND BUFFER-FUNDS FOR WOOL PRICE STABILISATION IN AUSTRALIA
Moir, Brian; Piggott, Roley R.
1991-01-01
In this paper a preliminary analysis is presented of a combined buffer-fund and buffer-stock as an alternative to a pure buffer-fund or a pure buffer stock for stabilising wool prices. The alternatives analysed are designed so that each provides the same prices to producers as did the Reserve Price Scheme over the period of analysis. Least-cost combinations of policy instruments are derived. The results show that there is considerable potential for cost savings to be made by combining buffer-...
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
Stanley Kubrick and B.F. Skinner : Is a Teaching Machine a Monolith ?
浜野, 保樹; ハマノ, ヤスキ; Yasuki, Hamano
1990-01-01
The teaching machine invented by B.F. Skinner was recog-nized as one of few clear achievements of scientific pedagogy and even appeared in SF. Arthur C. Clarke who wrote the script of the SF movie "2001: A Space Odyssey" with Stanley Kubrick wanted to scientifically define a monolith to be a God who had given intelligence to our ancestors. In other words, he wanted to describe a monolith as a teaching machine as well as a God. However Kubrick did not want to make clear about what a monolith i...
III–Vs on Si for photonic applications—A monolithic approach
International Nuclear Information System (INIS)
Wang, Zhechao; Junesand, Carl; Metaferia, Wondwosen; Hu, Chen; Wosinski, Lech; Lourdudoss, Sebastian
2012-01-01
Highlights: ► Monolithic evanescently coupled silicon laser (MECSL) structure treated. ► Optical mode profiles and thermal resistivity of MECSL optimized by simulation. ► MECSL through epitaxial lateral overgrowth (ELOG) of InP on Si exemplified. ► Passive waveguide in MECSL also acts as the defect filtering mask in ELOG. ► Growth of dislocation free thin InP layer on Si by ELOG for MECSL demonstrated. - Abstract: Epitaxial lateral overgrowth (ELOG) technology is demonstrated as a viable technology to realize monolithic integration of III-Vs on silicon. As an alternative to wafer-to-wafer bonding and die-to-wafer bonding, ELOG provides an attractive platform for fabricating discrete and integrated components in high volume at low cost. A possible route for monolithic integration of III–Vs on silicon for silicon photonics is exemplified by the case of a monolithic evanescently coupled silicon laser (MECSL) by combining InP on Si/SiO 2 through ELOG. Passive waveguide in MECSL also acts as the defect filtering mask in ELOG. The structural design of a monolithic evanescently coupled silicon laser (MECSL) and its thermal resistivity are established through simulations. Material studies to realize the above laser through ELOG are undertaken by studying appropriate ELOG pattern designs to achieve InP on narrow regions of silicon. We show that defect-free InP can be obtained on SiO 2 as the first step which paves the way for realizing active photonic devices on Si/SiO 2 waveguides, e.g. an MECSL.
Translucency and Strength of High Translucency Monolithic Zirconium Oxide Materials
2016-05-17
Zirconium -Oxide Materials presented at/published to the Journal of General Dentistry with MDWI 41-108, and has been assigned local file #16208. 2...Zirconia-Oxide Materials 6. TITLE OF MATERIAL TO BE PUBLISHED OR PRESENTED: Translucency and Strength of High-Translucency Monolithic Zirconium -Oxide...OBSOLETE 48. DATE Page 3 of 3 Pages Translucency and Strength of High-Translucency Monolithic Zirconium -Oxide Materials Abstract Dental materials
Prins, Daniel; Michalak, Marek
2011-01-01
Ca2+ is an important intracellular messenger affecting many diverse processes. In eukaryotic cells, Ca2+ storage is achieved within specific intracellular organelles, especially the endoplasmic/sarcoplasmic reticulum, in which Ca2+ is buffered by specific proteins known as Ca2+ buffers. Ca2+ buffers are a diverse group of proteins, varying in their affinities and capacities for Ca2+, but they typically also carry out other functions within the cell. The wide range of organelles containing Ca2+ and the evidence supporting cross-talk between these organelles suggest the existence of a dynamic network of organellar Ca2+ signaling, mediated by a variety of organellar Ca2+ buffers. PMID:21421925
Differential InP HEMT MMIC Amplifiers Embedded in Waveguides
Kangaslahti, Pekka; Schlecht, Erich; Samoska, Lorene
2009-01-01
Monolithic microwave integrated-circuit (MMIC) amplifiers of a type now being developed for operation at frequencies of hundreds of gigahertz contain InP high-electron-mobility transistors (HEMTs) in a differential configuration. The differential configuration makes it possible to obtain gains greater than those of amplifiers having the single-ended configuration. To reduce losses associated with packaging, the MMIC chips are designed integrally with, and embedded in, waveguide packages, with the additional benefit that the packages are compact enough to fit into phased transmitting and/or receiving antenna arrays. Differential configurations (which are inherently balanced) have been used to extend the upper limits of operating frequencies of complementary metal oxide/semiconductor (CMOS) amplifiers to the microwave range but, until now, have not been applied in millimeter- wave amplifier circuits. Baluns have traditionally been used to transform from single-ended to balanced configurations, but baluns tend to be lossy. Instead of baluns, finlines are used to effect this transformation in the present line of development. Finlines have been used extensively to drive millimeter- wave mixers in balanced configurations. In the present extension of the finline balancing concept, finline transitions are integrated onto the affected MMICs (see figure). The differential configuration creates a virtual ground within each pair of InP HEMT gate fingers, eliminating the need for inductive vias to ground. Elimination of these vias greatly reduces parasitic components of current and the associated losses within an amplifier, thereby enabling more nearly complete utilization of the full performance of each transistor. The differential configuration offers the additional benefit of multiplying (relative to the single-ended configuration) the input and output impedances of each transistor by a factor of four, so that it is possible to use large transistors that would otherwise have
Tetsuya, Saito; Nauta, Bram
2011-01-01
PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. SOLUTION: The operation amplifier comprises: a
Tetsuya, S.; Nauta, Bram
2007-01-01
PROBLEM TO BE SOLVED: To provide an operation amplifier which improves power source voltage removal ratios while assuring phase compensation characteristics, and therefore can be realized with a small-scale circuit and low power consumption. ; SOLUTION: The operation amplifier comprises: a
Li, Haibin; Liu, Chusheng; Wang, Qiqin; Zhou, Haibo; Jiang, Zhengjin
2016-10-21
In order to investigate the effect of charged groups present in hydrophilic monolithic stationary phases on their chromatographic properties, three charged hydrophilic monomers, i.e. N,N-dimethyl-N-acryloyloxyethyl-N-(3-sulfopropyl)ammonium betaine (SPDA), [2-(acryloyloxy)ethyl]trimethylammonium chloride (AETA), and 3-sulfopropyl acrylate potassium salt (SPA) were co-polymerized with the crosslinker N,N'-methylenebisacrylamide (MBA), respectively. The physicochemical properties of the three resulting charged hydrophilic monolithic columns were evaluated using scanning electron microscopy, ζ-potential analysis and micro-HPLC. High column efficiency was obtained on the three monolithic columns at a linear velocity of 1mm/s using thiourea as test compound. Comparative characterization of the three charged HILIC phases was then carried out using a set of model compounds, including nucleobases, nucleosides, benzoic acid derivatives, phenols, β-blockers and small peptides. Depending on the combination of stationary phase/mobile phase/solute, both hydrophilic interaction and other potential secondary interactions, including electrostatic interaction, hydrogen-bonding interaction, molecular shape selectivity, could contribute to the over-all retention of the analytes. Because of the strong electrostatic interaction provided by the quaternary ammonium groups in the poly (AETA-co-MBA) monolith, this cationic HILIC monolith exhibited the strongest retention for benzoic acid derivatives and small peptides with distorted peak shapes and the weakest retention for basic β-blockers. The sulfonyl groups on the poly (SPA-co-MBA) hydrophilic monolith could provide strong electrostatic attraction and hydrogen bonding for positively charged analytes and hydrogen-donor/acceptor containing analytes, respectively. Therefore, basic drugs, nucleobases and nucleotides exhibited the strongest retention on this anionic monolith. Because of the weak but distinct cation exchange properties of
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.
Covalent attachment of polymeric monolith to polyether ether ketone (PEEK) tubing.
Lv, Chunguang; Heiter, Jaana; Haljasorg, Tõiv; Leito, Ivo
2016-08-17
A new method of reproducible preparation of vinylic polymeric monolithic columns with a key step of covalently anchoring the monolith to PEEK surface is described. In order to chemically attach the polymer monolith to the tube wall, methacrylate functional groups were introduced onto PEEK surface by a three-step procedure, including surface etching, surface reduction and surface methacryloylation. The chemical state of the modified tubing surface was characterized by attenuated total reflectance infrared (ATR-IR) spectroscopy. It was found that the etching step is the key to successfully modifying the PEEK tubing surface. Poly(styrene-co-divinylbenzene) monoliths were in situ synthesized by thermally initiated free radical copolymerization within the confines of surface-vinylized PEEK tubings of dimensions close to ones conventionally used in HPLC and UHPLC (1.6 mm internal diameter, 10.0-12.5 cm length). Adhesion test was done by measuring the operating pressure drop, which the prepared stationary phases can withstand. Good pressure resistance, up to 140 bar/10 cm (flow rate 0.5 mL min(-1), acetonitrile as a mobile phase), indicates strong bonding of monolith to the tubing wall. The monolithic material was proven to have a permeability of 1.7 × 10 (-14) m(2), applying acetonitrile-water 70:30 (v/v) as a mobile phase. The column performance was reproducible from column to column and was evaluated via the isocratic separation of a series of alkylbenzenes in the reversed-phase mode (acetonitrile-water 70:30, v/v). The numbers of plates per meter at optimal flow rate were found to be between 26 000 and 32 000 for the different analytes. Copyright © 2016 Elsevier B.V. All rights reserved.
Liu, Kun; Tolley, H Dennis; Lee, Milton L
2012-03-02
Seven crosslinking monomers, i.e., 1,3-butanediol dimethacrylate (1,3-BDDMA), 1,4-butanediol dimethacrylate (1,4-BDDMA), neopentyl glycol dimethacrylate (NPGDMA), 1,5-pentanediol dimethacrylate (1,5-PDDMA), 1,6-hexanediol dimethacrylate (1,6-HDDMA), 1,10-decanediol dimethacrylate (1,10-DDDMA), and 1,12-dodecanediol dimethacrylate (1,12-DoDDMA), were used to synthesize highly cross-linked monolithic capillary columns for reversed-phase liquid chromatography (RPLC) of small molecules. Dodecanol and methanol were chosen as "good" and "poor" porogenic solvents, respectively, for these monoliths, and were investigated in detail to provide insight into the selection of porogen concentration using 1,12-DoDDMA. Isocratic elution of alkylbenzenes at a flow rate of 300 nL/min was conducted for all of the monoliths. Gradient elution of alkylbenzenes and alkylparabens provided high resolution separations. Optimized monoliths synthesized from all seven crosslinking monomers showed high permeability. Several of the monoliths demonstrated column efficiencies in excess of 50,000 plates/m. Monoliths with longer alkyl-bridging chains showed very little shrinking or swelling in solvents of different polarities. Column preparation was highly reproducible; the relative standard deviation (RSD) values (n=3) for run-to-run and column-to-column were less than 0.25% and 1.20%, respectively, based on retention times of alkylbenzenes. Copyright © 2012 Elsevier B.V. All rights reserved.
Distributed feedback laser amplifiers combining the functions of amplifiers and channel filters
DEFF Research Database (Denmark)
Wang, Z.; Durhuus, T.; Mikkelsen, Benny
1994-01-01
A dynamic model for distributed feedback amplifiers, including the mode coupled equations and the carrier rate equation, is established. The presented mode coupled equations have taken into account the interaction between fast changing optical signal and the waveguide with corrugations. By showin...... the possibility of amplifying 100 ps pulses without pulse broadening, we anticipate that a distributed feedback amplifier can be used as a combined amplifier and channel filter in high bit rate transmission systems....
Power-Combined GaN Amplifier with 2.28-W Output Power at 87 GHz
Fung, King Man; Ward, John; Chattopadhyay, Goutam; Lin, Robert H.; Samoska, Lorene A.; Kangaslahti, Pekka P.; Mehdi, Imran; Lambrigtsen, Bjorn H.; Goldsmith, Paul F.; Soria, Mary M.;
2011-01-01
Future remote sensing instruments will require focal plane spectrometer arrays with higher resolution at high frequencies. One of the major components of spectrometers are the local oscillator (LO) signal sources that are used to drive mixers to down-convert received radio-frequency (RF) signals to intermediate frequencies (IFs) for analysis. By advancing LO technology through increasing output power and efficiency, and reducing component size, these advances will improve performance and simplify architecture of spectrometer array systems. W-band power amplifiers (PAs) are an essential element of current frequency-multiplied submillimeter-wave LO signal sources. This work utilizes GaN monolithic millimeter-wave integrated circuit (MMIC) PAs developed from a new HRL Laboratories LLC 0.15- m gate length GaN semiconductor transistor. By additionally waveguide power combining PA MMIC modules, the researchers here target the highest output power performance and efficiency in the smallest volume achievable for W-band.
Wi, Jae-Hyung; Kim, Tae Gun; Kim, Jeong Won; Lee, Woo-Jung; Cho, Dae-Hyung; Han, Won Seok; Chung, Yong-Duck
2015-08-12
We selected a sputtered-Zn(O,S) film as a buffer material and fabricated a Cu(In,Ga)Se2 (CIGS) solar cell for use in monolithic tandem solar cells. A thermally stable buffer layer was required because it should withstand heat treatment during processing of top cell. Postannealing treatment was performed on a CIGS solar cell in vacuum at temperatures from 300-500 °C to examine its thermal stability. Serious device degradation particularly in VOC was observed, which was due to the diffusion of thermally activated constituent elements. The elements In and Ga tend to out-diffuse to the top surface of the CIGS, while Zn diffuses into the interface of Zn(O,S)/CIGS. Such rearrangement of atomic fractions modifies the local energy band gap and band alignment at the interface. The notch-shape induced at the interface after postannealing could function as an electrical trap during electron transport, which would result in the reduction of solar cell efficiency.
III-Vs on Si for photonic applications-A monolithic approach
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhechao, E-mail: Zhechao.Wang@intec.ugent.be [School of ICT, Royal Institute of Technology, Electrum 229, Isafjordsgatan 22, 164 40 Kista (Sweden); Junesand, Carl; Metaferia, Wondwosen; Hu, Chen; Wosinski, Lech [School of ICT, Royal Institute of Technology, Electrum 229, Isafjordsgatan 22, 164 40 Kista (Sweden); Lourdudoss, Sebastian, E-mail: slo@kth.se [School of ICT, Royal Institute of Technology, Electrum 229, Isafjordsgatan 22, 164 40 Kista (Sweden)
2012-10-01
Highlights: Black-Right-Pointing-Pointer Monolithic evanescently coupled silicon laser (MECSL) structure treated. Black-Right-Pointing-Pointer Optical mode profiles and thermal resistivity of MECSL optimized by simulation. Black-Right-Pointing-Pointer MECSL through epitaxial lateral overgrowth (ELOG) of InP on Si exemplified. Black-Right-Pointing-Pointer Passive waveguide in MECSL also acts as the defect filtering mask in ELOG. Black-Right-Pointing-Pointer Growth of dislocation free thin InP layer on Si by ELOG for MECSL demonstrated. - Abstract: Epitaxial lateral overgrowth (ELOG) technology is demonstrated as a viable technology to realize monolithic integration of III-Vs on silicon. As an alternative to wafer-to-wafer bonding and die-to-wafer bonding, ELOG provides an attractive platform for fabricating discrete and integrated components in high volume at low cost. A possible route for monolithic integration of III-Vs on silicon for silicon photonics is exemplified by the case of a monolithic evanescently coupled silicon laser (MECSL) by combining InP on Si/SiO{sub 2} through ELOG. Passive waveguide in MECSL also acts as the defect filtering mask in ELOG. The structural design of a monolithic evanescently coupled silicon laser (MECSL) and its thermal resistivity are established through simulations. Material studies to realize the above laser through ELOG are undertaken by studying appropriate ELOG pattern designs to achieve InP on narrow regions of silicon. We show that defect-free InP can be obtained on SiO{sub 2} as the first step which paves the way for realizing active photonic devices on Si/SiO{sub 2} waveguides, e.g. an MECSL.
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.
Solid State Characterizations of Long-Term Leached Cast Stone Monoliths
Energy Technology Data Exchange (ETDEWEB)
Asmussen, Robert M.; Pearce, Carolyn I.; Parker, Kent E.; Miller, Brian W.; Lee, Brady D.; Buck, Edgar C.; Washton, Nancy M.; Bowden, Mark E.; Lawter, Amanda R.; McElroy, Erin M.; Serne, R Jeffrey
2016-09-30
This report describes the results from the solid phase characterization of six Cast Stone monoliths from the extended leach tests recently reported on (Serne et al. 2016),that were selected for characterization using multiple state-of-the-art approaches. The Cast Stone samples investigated were leached for > 590 d in the EPA Method 1315 test then archived for > 390 d in their final leachate. After reporting the long term leach behavior of the monoliths (containing radioactive 99Tc and stable 127I spikes and for original Westsik et al. 2013 fabricated monoliths, 238U), it was suggested that physical changes to the waste forms and a depleting inventory of contaminants of potential concern may mean that effective diffusivity calculations past 63 d should not be used to accurately represent long-term waste form behavior. These novel investigations, in both length of leaching time and application of solid state techniques, provide an initial arsenal of techniques which can be utilized to perform such Cast Stone solid phase characterization work, which in turn can support upcoming performance assessment maintenance. The work was performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to characterize several properties of the long- term leached Cast Stone monolith samples.
Fabrication and Characterisation of Low-noise Monolithic Mode-locked Lasers
DEFF Research Database (Denmark)
Larsson, David
2007-01-01
This thesis deals with the fabrication and characterisation of monolithic semiconductor mode-locked lasers for use in optical communication systems. Other foreseeable applications may be as sources in microwave photonics and optical sampling. The thesis also deals with the design and fabrication...... of intracavity monolithically integrated filters. The common dnominator among the diffrent parts of the thesis is how to achieve and measure the lowest possible noise. Achieving low noise has been pinpointed as one of the most important and difficult challenges for semiconductor mode-locked lasers. The main...... result of this thesis are a fabrication process of a monolithic and deeply etched distributed Bragg reflector and a characterisation system for measurement of quantum limitid timing noise at high repetition rates. The Bragg reflector is a key component in achieving transform limited pulses with low noise...
Recent progress in low-temperature-process monolithic three dimension technology
Yang, Chih-Chao; Hsieh, Tung-Ying; Huang, Wen-Hsien; Shen, Chang-Hong; Shieh, Jia-Min; Yeh, Wen-Kuan; Wu, Meng-Chyi
2018-04-01
Monolithic three-dimension (3D) integration is an ultimate alternative method of fabricating high density, high performance, and multi-functional integrated circuits. It offers the promise of being a new approach to increase system performance. How to manage the thermal impact of multi-tiered processes, such as dopant activation, source/drain silicidation, and channel formation, and to prevent the degradation of pre-existing devices/circuits become key challenges. In this paper, we provide updates on several important monolithic 3D works, particularly in sequentially stackable channels, and our recent achievements in monolithic 3D integrated circuit (3D-IC). These results indicate that the advanced 3D architecture with novel design tools enables ultrahigh-density stackable circuits to have superior performance and low power consumption for future artificial intelligence (AI) and internet of things (IoTs) application.
Monolithic fiber optic sensor assembly
Sanders, Scott
2015-02-10
A remote sensor element for spectrographic measurements employs a monolithic assembly of one or two fiber optics to two optical elements separated by a supporting structure to allow the flow of gases or particulates therebetween. In a preferred embodiment, the sensor element components are fused ceramic to resist high temperatures and failure from large temperature changes.
Towards a Technique for Extracting Microservices from Monolithic Enterprise Systems
Levcovitz, Alessandra; Terra, Ricardo; Valente, Marco Tulio
2016-01-01
The idea behind microservices architecture is to develop a single large, complex application as a suite of small, cohesive, independent services. On the other way, monolithic systems get larger over the time, deviating from the intended architecture, and becoming risky and expensive to evolve. This paper describes a technique to identify and define microservices on monolithic enterprise systems. As the major contribution, our evaluation shows that our approach was able to identify relevant ca...
Antagonist wear of monolithic zirconia crowns after 2 years.
Lohbauer, Ulrich; Reich, Sven
2017-05-01
The aim of this study was to evaluate the amount of wear on the antagonist occlusal surfaces of clinically placed monolithic zirconia premolar and molar crowns (LAVA Plus, 3M ESPE). Fourteen in situ monolithic zirconia crowns and their opposing antagonists (n = 26) are the subject of an ongoing clinical trial and have been clinically examined at baseline and after 24 months. Silicone impressions were taken and epoxy replicas produced for qualitative SEM analysis and quantitative analysis using optical profilometry. Based on the baseline replicas, the follow-up situation has been scanned and digitally matched with the initial topography in order to calculate the mean volume loss (in mm 3 ) as well as the mean maximum vertical loss (in mm) after 2 years in service. The mean volume loss for enamel antagonist contacts (n = 7) was measured to 0.361 mm 3 and the mean of the maximum vertical loss to 0.204 mm. The mean volume loss for pure ceramic contacts (n = 10) was measured to 0.333 mm 3 and the mean of the maximum vertical loss to 0.145 mm. The wear rates on enamel contacts were not significantly different from those measured on ceramic antagonists. Based on the limitations of this study, it can be concluded for the monolithic zirconia material LAVA Plus that the measured wear rates are in consensus with other in vivo studies on ceramic restorations. Further, that no significant difference was found between natural enamel antagonists and ceramic restorations as antagonists. The monolithic zirconia restorations do not seem to be affected by wear within the first 2 years. The monolithic zirconia crowns (LAVA Plus) show acceptable antagonist wear rates after 2 years in situ, regardless of natural enamel or ceramics as antagonist materials.
International Nuclear Information System (INIS)
Stine, R.D.; Ross, G.F.; Silvernail, C.
1979-01-01
The overall design of the Antares laser power amplifier is discussed. The power amplifier is the last stage of amplification in the 100-kJ Antares laser. In the power amplifier a single, cylindrical, grid-controlle, cold-cathode electron gun is surrounded by 12 large-aperture CO 2 electron-beam sustained laser discharge sectors. Each power amplifier will deliver 18 kJ and the six modules used in Antares will produce the required 100 kJ for delivery to the target. A large-scale interaction between optical, mechanical, and electrical disciplines is required to meet the design objectives. Significant component advances required by the power amplifier design are discussed
A monolithic integrated photonic microwave filter
Fandiño, Javier S.; Muñoz, Pascual; Doménech, David; Capmany, José
2017-02-01
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.
Monolithically integrated 8-channel WDM reflective modulator
Stopinski, S.T.; Malinowski, M.; Piramidowicz, R.; Smit, M.K.; Leijtens, X.J.M.
2013-01-01
In this work the design and characterization of a monolithically integrated photonic circuit acting as a reflective modulator for eight WDM channels is presented. The chip was designed and fabricated in a generic integration technology
Monolithic Integrated Ceramic Waveguide Filters
Hunter, IC; Sandhu, MY
2014-01-01
Design techniques for a new class of integrated monolithic high permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled TEM filters with the same unloaded Q-Factor. Designs for both chebyshev and asymmetric generalized chebyshev filter are presented, with experimental results for an 1800 MHz chebyshev filter showing excellent agreement with theory.
Amplification factor variable amplifier
Akitsugu, Oshita; Nauta, Bram
2007-01-01
PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ; SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and
Directory of Open Access Journals (Sweden)
Milka Hutagalung
2016-07-01
Full Text Available We consider simulation games played between Spoiler and Duplicator on two Büchi automata in which the choices made by Spoiler can be buffered by Duplicator in two different buffers before she executes them on her structure. Previous work on such games using a single buffer has shown that they are useful to approximate language inclusion problems. We study the decidability and complexity and show that games with two buffers can be used to approximate corresponding problems on finite transducers, i.e. the inclusion problem for rational relations over infinite words.
Environmentally Benign Production of Stretchable and Robust Superhydrophobic Silicone Monoliths.
Davis, Alexander; Surdo, Salvatore; Caputo, Gianvito; Bayer, Ilker S; Athanassiou, Athanassia
2018-01-24
Superhydrophobic materials hold an enormous potential in sectors as important as aerospace, food industries, or biomedicine. Despite this great promise, the lack of environmentally friendly production methods and limited robustness remain the two most pertinent barriers to the scalability, large-area production, and widespread use of superhydrophobic materials. In this work, highly robust superhydrophobic silicone monoliths are produced through a scalable and environmentally friendly emulsion technique. It is first found that stable and surfactantless water-in-polydimethylsiloxane (PDMS) emulsions can be formed through mechanical mixing. Increasing the internal phase fraction of the precursor emulsion is found to increase porosity and microtexture of the final monoliths, rendering them superhydrophobic. Silica nanoparticles can also be dispersed in the aqueous internal phase to create micro/nanotextured monoliths, giving further improvements in superhydrophobicity. Due to the elastomeric nature of PDMS, superhydrophobicity can be maintained even while the material is mechanically strained or compressed. In addition, because of their self-similarity, the monoliths show outstanding robustness to knife-scratch, tape-peel, and finger-wipe tests, as well as rigorous sandpaper abrasion. Superhydrophobicity was also unchanged when exposed to adverse environmental conditions including corrosive solutions, UV light, extreme temperatures, and high-energy droplet impact. Finally, important properties for eventual adoption in real-world applications including self-cleaning, stain-repellence, and blood-repellence are demonstrated.
Temperature Buffer Test. Measurements of water content and density of the excavated buffer material
Energy Technology Data Exchange (ETDEWEB)
Johannesson, Lars-Erik [Clay Technology AB, Lund (Sweden)
2010-12-15
TBT (Temperature Buffer Test) is a joint project between SKB/ANDRA and supported by ENRESA (modeling) and DBE (instrumentation), which aims at understanding and modeling the thermo-hydromechanical behavior of buffers made of swelling clay submitted to high temperatures (over 100 deg C) during the water saturation process. The test was carried out at the - 420 m level in Aespoe HRL in a 8 meters deep and 1.76 m diameter deposition hole, with two heaters (3 m long, 0.6 m diameter), surrounded by a MX-80 bentonite buffer and a confining plug on top anchored with 9 rods. It was installed during spring 2003. The bentonite around upper heater was removed during the period October - December 2009 and the buffer around the lower heater was removed during January - Mars 2010. During dismantling of the buffer, samples were taken on which analyses were made. This report describes the work with the deteroemoeination of the water content and the density of the taken samples. Most of the samples were taken from the buffer by core drilling from the upper surface of each installed bentonite block. The cores had a diameter of about 50 mm and a maximum length equal to the original height of the bentonite blocks (about 500 mm). The water content of the buffer was determined by drying a sample at a temperature of 105 deg C for 24 h and the bulk density was determined by weighing a sample both in the air and immerged in paraffin oil with known density. The water content, dry density, degree of saturation and void ratio of the buffer were then plotted. The plots show that all parts of the buffer had taken up water and the degree of saturation of the buffer varied between 90 - 100%. Large variation in the dry density of the buffer was also observed.
Amplification factor variable amplifier
Akitsugu, Oshita; Nauta, Bram
2010-01-01
PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ;SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and can
Optical properties of pre-colored dental monolithic zirconia ceramics.
Kim, Hee-Kyung; Kim, Sung-Hun
2016-12-01
The purposes of this study were to evaluate the optical properties of recently marketed pre-colored monolithic zirconia ceramics and to compare with those of veneered zirconia and lithium disilicate glass ceramics. Various shades of pre-colored monolithic zirconia, veneered zirconia, and lithium disilicate glass ceramic specimens were tested (17.0×17.0×1.5mm, n=5). CIELab color coordinates were obtained against white, black, and grey backgrounds with a spectrophotometer. Color differences of the specimen pairs were calculated by using the CIEDE2000 (ΔE 00 ) formula. The translucency parameter (TP) was derived from ΔE 00 of the specimen against a white and a black background. X-ray diffraction was used to determine the crystalline phases of monolithic zirconia specimens. Data were analyzed with 1-way ANOVA, Scheffé post hoc, and Pearson correlation testing (α=0.05). For different shades of the same ceramic brand, there were significant differences in L * , a * , b * , and TP values in most ceramic brands. With the same nominal shade (A2), statistically significant differences were observed in L * , a * , b * , and TP values among different ceramic brands and systems (Pceramics of the corresponding nominal shades ranged beyond the acceptability threshold. Due to the high L * values and low a * and b * values, pre-colored monolithic zirconia ceramics can be used with additional staining to match neighboring restorations or natural teeth. Due to their high value and low chroma, unacceptable color mismatch with adjacent ceramic restorations might be expected. Copyright © 2016 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Juvankoski, M.
2013-08-01
Posiva's spent nuclear fuel disposal is based on the KBS-3V concept and on the characteristics of the Olkiluoto site. In this concept single canisters containing spent nuclear fuel surrounded by a bentonite buffer are emplaced in individual vertical boreholes drilled in the floor of deposition tunnels in bedrock at about 420 m depth below ground level. Disk type bentonite blocks are installed at the bottom of the hole and on the top of the disposal canister. Ring type bentonite blocks surround the canisters. This report describes the detailed design of the buffer for a KBS-3V repository. The report presents the design basis, the reference design, and summarises the performance analyses carried out for the design. This report addresses aspects concerning the manufacture, quality control, mechanical strength, chemical resistance, thermal dimensioning, handling of buffer components and material ageing phenomena including the effect of radiation. Interaction of buffer and other engineered barriers are included in the study. The long-term evolution of the repository and its effective drivers are considered if they have an impact on the buffer performance but operational safety aspects are also included because they may affect long-term safety. (orig.)
New 'monolithic' templates and improved protocols for soft lithography and microchip fabrication
International Nuclear Information System (INIS)
Pallandre, Antoine; Pal, Debjani; Lambert, Bertrand de; Viovy, Jean-Louis; Fuetterer, Claus
2006-01-01
We report a new method for fast prototyping and fabrication of polydimethylsiloxane (PDMS) and plastic microfluidic chips. These methods share in common the preparation of monolithic masters which includes the fabrication of the planar support, the 'negative pattern' of the microchannels and the fluidic connectors. The monolithic templates are extremely robust compared to conventional ones made of silicon and SU-8, and easier to produce and cheaper than all-silicon or electroplated templates. In contrast to the above-mentioned methods, our process allows one to cast both micrometre- (e.g. the microchannel) and millimetre-sized structures (e.g. the fluidic connection to the outer world) in a single fabrication step. The 'monolithic template' strategy can be used to fabricate both elastomeric (e.g. poly(dimethyl siloxane (PDMS)) polyester thermoset masters and glassy polymeric (e.g. cyclic olefin copolymer (COC)) devices. In this study we also report on one step fabrication of elastomer chips and on surface modifications of the above mentioned monolithically fabricated masters in order to improve separation of the chip from the template
Failure analysis of various monolithic posterior aesthetic dental crowns using finite element method
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.
Effect of pore size on performance of monolithic tube chromatography of large biomolecules.
Podgornik, Ales; Hamachi, Masataka; Isakari, Yu; Yoshimoto, Noriko; Yamamoto, Shuichi
2017-11-01
Effect of pore size on the performance of ion-exchange monolith tube chromatography of large biomolecules was investigated. Radial flow 1 mL polymer based monolith tubes of different pore sizes (1.5, 2, and 6 μm) were tested with model samples such as 20 mer poly T-DNA, basic proteins, and acidic proteins (molecular weight 14 000-670 000). Pressure drop, pH transient, the number of binding site, dynamic binding capacity, and peak width were examined. Pressure drop-flow rate curves and dynamic binding capacity values were well correlated with the nominal pore size. While duration of the pH transient curves depends on the pore size, it was found that pH duration normalized on estimated surface area was constant, indicating that the ligand density is the same. This was also confirmed by the constant number of binding site values being independent of pore size. The peak width values were similar to those for axial flow monolith chromatography. These results showed that it is easy to scale up axial flow monolith chromatography to radial flow monolith tube chromatography by choosing the right pore size in terms of the pressure drop and capacity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Monolithic pixels on moderate resistivity substrate and sparsifying readout architecture
Giubilato, P; Snoeys, W; Bisello, D; Marchioro, A; Battaglia, M; Demaria, L; Mansuy, S C; Pantano, D; Rousset, J; Mattiazzo, S; Kloukinas, K; Potenza, A; Ikemoto, Y; Rivetti, A; Chalmet, P; Mugnier, H; Silvestrin, L
2013-01-01
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 Fe-55 double peak at room temperature. To achieve high granularity (10-20 mu m pitch pixels) over large detector areas maintaining high readout speed, a complet...
CMOS Current-mode Operational Amplifier
DEFF Research Database (Denmark)
Kaulberg, Thomas
1992-01-01
current-mode feedback amplifier or a constant bandwidth in a transimpedance feedback amplifier. The amplifier is found to have a gain bandwidth product of 8 MHz, an offset current of 0.8 ¿A (signal-range ±700¿A) and a (theoretically) unlimited slew-rate. The amplifier is realized in a standard CMOS 2......A fully differential-input differential-output current-mode operational amplifier (COA) is described. The amplifier utilizes three second generation current-conveyors (CCII) as the basic building blocks. It can be configured to provide either a constant gain-bandwidth product in a fully balanced...
THE CHANGE IN DEFORMATION CHARACTERISTICS OF CONCRETE MONOLITHIC HIGH-RISE BUILDINGS
Directory of Open Access Journals (Sweden)
V. V. Punahin
2009-03-01
Full Text Available In the article results of studies of deformation features of concrete on actuate cement for monolithic high-altitude buildings are presented. It is shown that in construction of the high-altitude monolithic buildings in a summer period of a year one should take into account the character of changing the concrete elasticity and plasticity in time, which differs from the same indices for the concrete of normal hardening.
Qin, Zhang-Na; Yu, Qiong-Wei; Wang, Ren-Qi; Feng, Yu-Qi
2018-04-27
A mixed-mode polymer monolithic column functionalized by arsonic acid groups was prepared by single-step in situ copolymerization of monomers p-methacryloylaminophenylarsonic acid (p-MAPHA) and pentaerythritol triacrylate (PETA). The prepared poly(p-MAPHA-co-PETA) monolithic column has a homogeneous monolithic structure with good permeability and mechanical stability. Zeta potential measurements reveal that the monolithic stationary phase holds a negative surface charge when the mobile phase resides in the pH range of 3.0-8.0. The retention mechanisms of prepared monolithic column are explored by the separation of selected polycyclic aromatic hydrocarbons (PAHs), nucleosides, and three basic compounds. The results indicate that the column functions in three different separation modes associated with reversed-phase chromatography based on hydrophobic interaction, hydrophilic interaction chromatography, and cation-exchange chromatography. The column efficiency of prepared monolithic column is estimated to be 70,000 and 76,000 theoretical plates/m for thiourea and naphthalene, respectively, at a linear flow velocity of 0.85 mm/s using acetonitrile/H 2 O (85/15, v/v) as the mobile phase. Furthermore, an analysis of the retention factors obtained for the PAHs indicates that the prepared monolithic column exhibits good reproducibility with relative standard deviations of 2.9%, 4.0%, and 4.7% based on run-to-run injections, column-to-column preparation, and batch-to-batch preparation, respectively. Finally, we investigate the separation performance of the proposed monolithic column for select phenols, sulfonamides, nucleobases and nucleosides. Copyright © 2018 Elsevier B.V. All rights reserved.
International Nuclear Information System (INIS)
Vazquez, Mercedes; Paull, Brett
2010-01-01
This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed.
Dostal, Jiri
1993-01-01
This book provides the reader with the practical knowledge necessary to select and use operational amplifier devices. It presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits.Provides the reader with practical knowledge necessary to select and use operational amplifier devices. Presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits
Monolithic millimeter-wave and picosecond electronic technologies
International Nuclear Information System (INIS)
Talley, W.K.; Luhmann, N.C.
1996-01-01
Theoretical and experimental studies into monolithic millimeter-wave and picosecond electronic technologies have been undertaken as a collaborative project between the Lawrence Livermore National Laboratory (LLNL) and the University of California Department of Applied Science Coherent Millimeter-Wave Group under the auspices of the Laboratory Directed Research and Development Program at LLNL. The work involves the design and fabrication of monolithic frequency multiplier, beam control, and imaging arrays for millimeter-wave imaging and radar, as well as the development of high speed nonlinear transmission lines for ultra-wideband radar imaging, time domain materials characterization and magnetic fusion plasma applications. In addition, the Coherent Millimeter-Wave Group is involved in the fabrication of a state-of-the-art X-band (∼8-11 GHz) RF photoinjector source aimed at producing psec high brightness electron bunches for advanced accelerator and coherent radiation generation studies
Silicon monolithic microchannel-cooled laser diode array
International Nuclear Information System (INIS)
Skidmore, J. A.; Freitas, B. L.; Crawford, J.; Satariano, J.; Utterback, E.; DiMercurio, L.; Cutter, K.; Sutton, S.
2000-01-01
A monolithic microchannel-cooled laser diode array is demonstrated that allows multiple diode-bar mounting with negligible thermal cross talk. The heat sink comprises two main components: a wet-etched Si layer that is anodically bonded to a machined glass block. The continuous wave (cw) thermal resistance of the 10 bar diode array is 0.032 degree sign C/W, which matches the performance of discrete microchannel-cooled arrays. Up to 1.5 kW/cm 2 is achieved cw at an emission wavelength of ∼808 nm. Collimation of a diode array using a monolithic lens frame produced a 7.5 mrad divergence angle by a single active alignment. This diode array offers high average power/brightness in a simple, rugged, scalable architecture that is suitable for large two-dimensional areas. (c) 2000 American Institute of Physics
Ban, Lu; Han, Xu; Wang, Xian-Hua; Huang, Yan-Ping; Liu, Zhao-Sheng
2013-10-01
To obtain fast separation, ionic liquids were used as porogens first in combination with reversible addition-fragmentation chain transfer (RAFT) polymerization to prepare a new type of molecularly imprinted polymer (MIP) monolith. The imprinted monolithic column was synthesized using a mixture of carprofen (template), 4-vinylpyridine, ethylene glycol dimethacrylate, [BMIM]BF4, and chain transfer agent (CTA). Some polymerization factors, such as template-monomer molar ratio, the degree of crosslinking, the composition of the porogen, and the content of CTA, on the column efficiency and imprinting effect of the resulting MIP monolith were systematically investigated. Affinity screening of structurally similar compounds with the template can be achieved in 200 s on the MIP monolith due to high column efficiency (up to 12,070 plates/m) and good column permeability. Recognition mechanism of the imprinted monolith was also investigated.
Monoliths of activated carbon from coconut shell and impregnation with nickel and copper
International Nuclear Information System (INIS)
Giraldo, Liliana; Moreno, Juan
2008-01-01
A series of different monoliths of activated carbon were prepared from coconut shell By means of chemical activation with phosphoric acid at different concentrations Without using binders or plastics. The monolith that developed the biggest surface area was impregnated by humidic route with solutions of Ni and Cu at different molar relations. The structures were characterized by N2 adsorption at 77 K, and the morphology was explored by means of scanning electron microscopy. The carbonaceous materials obtained, Nickel-Copper-Monolith, were analyzed by Thermal Programmed Reduction (TPR). The experimental results indicated that the activation with the acid generated a micro porosity, with micropores volume between 0.40 and 0.81 cm 3 g-1 and surface areas between 703 and 1450 m 2 g-1, and a good mechanical properties. It shows that, both the copper and the nickel, are fixed to the monolith and TPR's results are interpreted when these molar relation are modified.
Poly(ethylenimine)-Functionalized Monolithic Alumina Honeycomb Adsorbents for CO2 Capture from Air.
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. © 2016 WILEY-VCH Verlag
Package Holds Five Monolithic Microwave Integrated Circuits
Mysoor, Narayan R.; Decker, D. Richard; Olson, Hilding M.
1996-01-01
Packages protect and hold monolithic microwave integrated circuit (MMIC) chips while providing dc and radio-frequency (RF) electrical connections for chips undergoing development. Required to be compact, lightweight, and rugged. Designed to minimize undesired resonances, reflections, losses, and impedance mismatches.
CMOS Current-mode Operational Amplifier
Kaulberg, Thomas
1992-01-01
A fully differential-input differential-output current-mode operational amplifier (COA) is described. The amplifier utilizes three second generation current-conveyors (CCII) as the basic building blocks. It can be configured to provide either a constant gain-bandwidth product in a fully balanced current-mode feedback amplifier or a constant bandwidth in a transimpedance feedback amplifier. The amplifier is found to have a gain bandwidth product of 8 MHz, an offset current of 0.8 ¿A (signal-r...
International Nuclear Information System (INIS)
Wang Yu; Deng Qiliang; Fang Guozhen; Pan Mingfei; Yu Yang; Wang Shuo
2012-01-01
Highlights: ► ILs as functional monomer for capillary monolithic column. ► Separation of alkylbenzenes, thiourea analogues, and amino acids. ► The column generate a stable reversed EOF from pH 2.0 to 12.0. ► The column efficiency of 147,000 plates m −1 was obtained for thiourea. - Abstract: A novel ionic liquid (IL) monolithic capillary column was successfully prepared by thermal free radical copolymerization of IL (1-vinyl-3-octylimidazolium chloride, ViOcIm + Cl − ) together with lauryl methacrylate (LMA) as the binary functional monomers and ethylene dimethacrylate (EDMA) as the cross-linker in binary porogen. The proportion of monomers, porogens and cross-linker in the polymerization mixture was optimized in detail. The resulting IL-monolithic column could not only generate a stable reversed electroosmotic flow (EOF) in a wide pH range (2.0–12.0), but also effectively eliminate the wall adsorption of the basic analytes. The obtained IL-monolithic columns were examined by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). These results indicated that the IL-monolithic capillary column possessed good pore properties, mechanical stability and permeability. The column performance was also evaluated by separating different kinds of compounds, such as alkylbenzenes, thiourea and its analogues, and amino acids. The lowest plate height of ∼6.8 μm was obtained, which corresponded to column efficiency (theoretical plates, N) of ∼147,000 plates m −1 for thiourea. ILs, as a new type of functional monomer, present a promising option in the fabrication of the organic polymer-based monolithic columns in CEC.
EROIC: a BiCMOS pseudo-gaussian shaping amplifier for high-resolution X-ray spectroscopy
Buzzetti, Siro; Guazzoni, Chiara; Longoni, Antonio
2003-10-01
We present the design and complete characterization of a fifth-order pseudo-gaussian shaping amplifier with 1 μs shaping time. The circuit is optimized for the read-out of signals coming from Silicon Drift Detectors for high-resolution X-ray spectroscopy. The novelty of the designed chip stands in the use of a current feedback loop to place the poles in the desired position on the s-plane. The amplifier has been designed in 0.8 μm BiCMOS technology and fully tested. The EROIC chip comprises also the peak stretcher, the peak detector, the output buffer to drive the external ADC and the pile-up rejection system. The circuit needs a single +5 V power supply and the dissipated power is 5 mW per channel. The digital outputs can be directly coupled to standard digital CMOS ICs. The measured integral-non-linearity of the whole chip is below 0.05% and the achieved energy resolution at the Mn Kα line detected by a 5 mm 2 Peltier-cooled Silicon Drift Detector is 167 eV FWHM.
EROIC: a BiCMOS pseudo-gaussian shaping amplifier for high-resolution X-ray spectroscopy
International Nuclear Information System (INIS)
Buzzetti, Siro; Guazzoni, Chiara; Longoni, Antonio
2003-01-01
We present the design and complete characterization of a fifth-order pseudo-gaussian shaping amplifier with 1 μs shaping time. The circuit is optimized for the read-out of signals coming from Silicon Drift Detectors for high-resolution X-ray spectroscopy. The novelty of the designed chip stands in the use of a current feedback loop to place the poles in the desired position on the s-plane. The amplifier has been designed in 0.8 μm BiCMOS technology and fully tested. The EROIC chip comprises also the peak stretcher, the peak detector, the output buffer to drive the external ADC and the pile-up rejection system. The circuit needs a single +5 V power supply and the dissipated power is 5 mW per channel. The digital outputs can be directly coupled to standard digital CMOS ICs. The measured integral-non-linearity of the whole chip is below 0.05% and the achieved energy resolution at the Mn Kα line detected by a 5 mm 2 Peltier-cooled Silicon Drift Detector is 167 eV FWHM
A Ferrite LTCC-Based Monolithic SIW Phased Antenna Array
Nafe, Ahmed A.; Ghaffar, Farhan A.; Farooqui, Muhammad Fahad; Shamim, Atif
2016-01-01
In this work, we present a novel configuration for realizing monolithic SIW-based phased antenna arrays using Ferrite LTCC technology. Unlike the current common schemes for realizing SIW phased arrays that rely on surface-mount component (p-i-n diodes, etc) for controlling the phase of the individual antenna elements, here the phase is tuned by biasing of the ferrite filling of the SIW. This approach eliminates the need for mounting of any additional RF components and enables seamless monolithic integration of phase shifters and antennas in SIW technology. As a proof of concept, a two-element slotted SIW-based phased array is designed, fabricated and measured. The prototype exhibits a gain of 4.9 dBi at 13.2 GHz and a maximum E-plane beam-scanning of 28 degrees using external windings for biasing the phase shifters. Moreover, the array can achieve a maximum beam-scanning of 19 degrees when biased with small windings that are embedded in the package. This demonstration marks the first time a fully monolithic SIW-based phased array is realized in Ferrite LTCC technology and paves the way for future larger-size implementations.
A Ferrite LTCC-Based Monolithic SIW Phased Antenna Array
Nafe, Ahmed
2016-11-17
In this work, we present a novel configuration for realizing monolithic SIW-based phased antenna arrays using Ferrite LTCC technology. Unlike the current common schemes for realizing SIW phased arrays that rely on surface-mount component (p-i-n diodes, etc) for controlling the phase of the individual antenna elements, here the phase is tuned by biasing of the ferrite filling of the SIW. This approach eliminates the need for mounting of any additional RF components and enables seamless monolithic integration of phase shifters and antennas in SIW technology. As a proof of concept, a two-element slotted SIW-based phased array is designed, fabricated and measured. The prototype exhibits a gain of 4.9 dBi at 13.2 GHz and a maximum E-plane beam-scanning of 28 degrees using external windings for biasing the phase shifters. Moreover, the array can achieve a maximum beam-scanning of 19 degrees when biased with small windings that are embedded in the package. This demonstration marks the first time a fully monolithic SIW-based phased array is realized in Ferrite LTCC technology and paves the way for future larger-size implementations.
Ladner, Y; Cretier, G; Faure, K
2015-01-01
Electrochromatography (EC) on a porous monolithic stationary phase prepared within the channels of a microsystem is an attractive alternative for on-chip separation. It combines the separation mechanisms of electrophoresis and liquid chromatography. Moreover, the porous polymer monolithic materials have become popular as stationary phase due to the ease and rapidity of fabrication via free radical photopolymerization. Here, we describe a hexyl acrylate (HA)-based porous monolith which is simultaneously in situ synthesized and anchored to the inner walls of the channel of a cyclic olefin copolymer (COC) device in only 2 min. The baseline separation of a mixture of neurotransmitters including six amino acids and two catecholamines is realized.
21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.
2010-04-01
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Buffered penicillin powder, penicillin powder with... FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered aqueous diluent. (a) Specifications. When reconstituted, each milliliter contains penicillin G procaine equivalent...
Simplified design of IC amplifiers
Lenk, John
1996-01-01
Simplified Design of IC Amplifiers has something for everyone involved in electronics. No matter what skill level, this book shows how to design and experiment with IC amplifiers. For experimenters, students, and serious hobbyists, this book provides sufficient information to design and build IC amplifier circuits from 'scratch'. For working engineers who design amplifier circuits or select IC amplifiers, the book provides a variety of circuit configurations to make designing easier.Provides basics for all phases of practical design.Covers the most popular forms for amplif
Numerical Simulation of Fluid Dynamics in a Monolithic Column
Directory of Open Access Journals (Sweden)
Kazuhiro Yamamoto
2017-01-01
Full Text Available As for the measurement of polycyclic aromatic hydrocarbons (PAHs, ultra-performance liquid chromatography (UPLC is used for PAH identification and densitometry. However, when a solvent containing a substance to be identified passes through a column of UPLC, a dedicated high-pressure-proof device is required. Recently, a liquid chromatography instrument using a monolithic column technology has been proposed to reduce the pressure of UPLC. The present study tested five types of monolithic columns produced in experiments. To simulate the flow field, the lattice Boltzmann method (LBM was used. The velocity profile was discussed to decrease the pressure drop in the ultra-performance liquid chromatography (UPLC system.
Wang, Yu; Deng, Qi-Liang; Fang, Guo-Zhen; Pan, Ming-Fei; Yu, Yang; Wang, Shuo
2012-01-27
A novel ionic liquid (IL) monolithic capillary column was successfully prepared by thermal free radical copolymerization of IL (1-vinyl-3-octylimidazolium chloride, ViOcIm(+)Cl(-)) together with lauryl methacrylate (LMA) as the binary functional monomers and ethylene dimethacrylate (EDMA) as the cross-linker in binary porogen. The proportion of monomers, porogens and cross-linker in the polymerization mixture was optimized in detail. The resulting IL-monolithic column could not only generate a stable reversed electroosmotic flow (EOF) in a wide pH range (2.0-12.0), but also effectively eliminate the wall adsorption of the basic analytes. The obtained IL-monolithic columns were examined by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR). These results indicated that the IL-monolithic capillary column possessed good pore properties, mechanical stability and permeability. The column performance was also evaluated by separating different kinds of compounds, such as alkylbenzenes, thiourea and its analogues, and amino acids. The lowest plate height of ~6.8 μm was obtained, which corresponded to column efficiency (theoretical plates, N) of ~147,000 plates m(-1) for thiourea. ILs, as a new type of functional monomer, present a promising option in the fabrication of the organic polymer-based monolithic columns in CEC. Copyright © 2011 Elsevier B.V. All rights reserved.
Behavior of micro-particles in monolith ceramic membrane filtration with pre-coagulation.
Yonekawa, H; Tomita, Y; Watanabe, Y
2004-01-01
This paper is intended to clarify the characteristics unique to monolith ceramic membranes with pre-coagulation by referring to the behavior of micro-particles. Flow analysis and experiments have proved that monolith ceramic membranes show a unique flow pattern in the channels within the element, causing extremely rapid flocculation in the channel during dead-end filtration. It was assumed that charge-neutralized micro-particles concentrated near the membrane surface grow in size due to flocculation, and as a result, coarse micro-particles were taken up by the shearing force to flow out. As the dead end points of flow in all the channels are located near the end of the channels with higher filterability, most of the flocculated coarse particles are formed to a columnar cake intensively at the dead end point. Therefore cake layer forming on the membrane other than around the dead end point is alleviated. This behavior of particle flocculation and cake formation at the dead end point within the channels are unique characteristics of monolith ceramic membranes. This is why all monolith ceramic membrane water purification systems operating in Japan do not have pretreatment equipment for flocculation and sedimentation.
Novel porous fly-ash containing geopolymer monoliths for lead adsorption from wastewaters
Energy Technology Data Exchange (ETDEWEB)
Novais, Rui M., E-mail: ruimnovais@ua.pt; Buruberri, L.H.; Seabra, M.P.; Labrincha, J.A.
2016-11-15
Highlights: • Porous fly ash containing-geopolymer monoliths for lead adsorption were developed. • Geopolymers’ porosity and pH of the ion solution controls the adsorption capacity. • Lead adsorption by the geopolymer monoliths up to 6.34 mg/g was observed. • These novel adsorbents can be used in packed beds that are easily collected. • The reuse of biomass fly ash wastes as raw material ensures waste valorization. - Abstract: In this study novel porous biomass fly ash-containing geopolymer monoliths were produced using a simple and flexible procedure. Geopolymers exhibiting distinct total porosities (ranging from 41.0 to 78.4%) and low apparent density (between 1.21 and 0.44 g/cm{sup 3}) were fabricated. Afterwards, the possibility of using these innovative materials as lead adsorbents under distinct conditions was evaluated. Results demonstrate that the geopolymers’ porosity and the pH of the ion solution strongly affect the lead adsorption capacity. Lead adsorption by the geopolymer monoliths ranged between 0.95 and 6.34 mg{sub lead}/g{sub geopolymer}. More porous geopolymers presented better lead removal efficiency, while higher pH in the solution reduced their removal ability, since metal precipitation is enhanced. These novel geopolymeric monoliths can be used in packed beds that are easily collected when exhausted, which is a major advantage in comparison with the use of powdered adsorbents. Furthermore, their production encompasses the reuse of biomass fly-ash, mitigating the environmental impact associated with this waste disposal, while decreasing the adsorbents production costs.
Improved-Bandwidth Transimpedance Amplifier
Chapsky, Jacob
2009-01-01
The widest available operational amplifier, with the best voltage and current noise characteristics, is considered for transimpedance amplifier (TIA) applications where wide bandwidth is required to handle fast rising input signals (as for time-of-flight measurement cases). The added amplifier inside the TIA feedback loop can be configured to have slightly lower voltage gain than the bandwidth reduction factor.
Improving Water Quality With Conservation Buffers
Lowrance, R.; Dabney, S.; Schultz, R.
2003-12-01
Conservation buffer technologies are new approaches that need wider application. In-field buffer practices work best when used in combination with other buffer types and other conservation practices. Vegetative barriers may be used in combination with edge-of-field buffers to protect and improve their function and longevity by dispersing runoff and encouraging sediment deposition upslope of the buffer. It's important to understand how buffers can be managed to help reduce nutrient transport potential for high loading of nutrients from manure land application sites, A restored riparian wetland buffer retained or removed at least 59 percent of the nitrogen and 66 percent of the phosphorus that entered from an adjacent manure land application site. The Bear Creek National Restoration Demonstration Watershed project in Iowa has been the site of riparian forest buffers and filter strips creation; constructed wetlands to capture tile flow; stream-bank bioengineering; in-stream structures; and controlling livestock grazing. We need field studies that test various widths of buffers of different plant community compositions for their efficacy in trapping surface runoff, reducing nonpoint source pollutants in subsurface waters, and enhancing the aquatic ecosystem. Research is needed to evaluate the impact of different riparian grazing strategies on channel morphology, water quality, and the fate of livestock-associated pathogens and antibiotics. Integrating riparian buffers and other conservation buffers into these models is a key objective in future model development.
Recent Advances and Uses of Monolithic Columns for the Analysis of Residues and Contaminants in Food
Directory of Open Access Journals (Sweden)
Mónica Díaz-Bao
2015-02-01
Full Text Available Monolithic columns are gaining interest as excellent substitutes to conventional particle-packed columns. These columns show higher permeability and lower flow resistance than conventional liquid chromatography columns, providing high-throughput performance, resolution and separation in short run times. Monoliths possess also great potential for the clean-up and preparation of complex mixtures. In situ polymerization inside appropriate supports allows the development of several microextraction formats, such as in-tube solid-phase and pipette tip-based extractions. These techniques using porous monoliths offer several advantages, including miniaturization and on-line coupling with analytical instruments. Additionally, monoliths are ideal support media for imprinting template-specific sites, resulting in the so-called molecularly-imprinted monoliths, with ultra-high selectivity. In this review, time-saving LC columns and preparative applications applied to the analysis of residues and contaminants in food in 2010–2014 are described, focusing on recent improvements in design and with emphasis in automated on-line systems and innovative materials and formats.
CAISSON TYPE HOLLOW FLOOR SLABS OF MONOLITHIC MULTI-STOREYED BUILDINGS
Directory of Open Access Journals (Sweden)
Malakhova Anna Nikolaevna
2016-06-01
Full Text Available One of the disadvantages of building structures made of reinforced concrete is their considerable weight. One of the trends to decrease the weight of concrete structures, including floor slabs, is the arrangement of voids in the cross-sectional building structures. In Russian and foreign practice paper, cardboard and plastic tubes has been used for creation of voids in the construction of monolithic floor slabs. Lightweight concretes were also used for production of precast hollow core floor slabs. The article provides constructive solutions of precast hollow core floor slabs and solid monolithic slabs that were used in the construction of buildings before wide use of large precast hollow core floor slabs. The article considers the application of caisson hollow core floor slabs for modern monolithic multi-storeyed buildings. The design solutions of such floor slabs, experimental investigations and computer modeling of their operation under load were described in this article. The comparative analysis of the calculation results of computer models of a hollow slabs formed of rod or plastic elements showed the similarity of calculation results.
LePIX: First results from a novel monolithic pixel sensor
International Nuclear Information System (INIS)
Mattiazzo, S.; Battaglia, M.; Bisello, D.; Caselle, M.; Chalmet, P.; Demaria, N.; Giubilato, P.; Ikemoto, Y.; Kloukinas, K.; Mansuy, C.; Marchioro, A.; Mugnier, H.; Pantano, D.; Potenza, A.; Rivetti, A.; Rousset, J.; Silvestrin, L.; Snoeys, W.; Wyss, J.
2013-01-01
We present a monolithic pixel sensor developed in the framework of the LePIX project aimed at tracking/triggering tasks where high granularity, low power consumption, material budget, radiation hardness and production costs are a concern. The detector is built in a 90 nm CMOS process on a substrate of moderate resistivity. This maintains the advantages usually offered by Monolithic Active Pixel Sensors (MAPS), like a low input capacitance, having a single piece detector and using a standard CMOS production line, but offers charge collection by drift from a depleted region and therefore an excellent signal to noise ratio and a radiation tolerance superior to conventional undepleted MAPS. Measurement results obtained with the first prototypes from laser, radioactive source and beam test experiments are described. The excellent signal-to-noise performance is demonstrated by the capability of the device to separate the peaks in the spectrum of a 55 Fe source. We will also highlight the interaction between pixel cell design and architecture which points toward a very precise direction in the development of such depleted monolithic pixel devices for high energy physics
Millimeter-wave power amplifiers
du Preez, Jaco
2017-01-01
This book provides a detailed review of millimeter-wave power amplifiers, discussing design issues and performance limitations commonly encountered in light of the latest research. Power amplifiers, which are able to provide high levels of output power and linearity while being easily integrated with surrounding circuitry, are a crucial component in wireless microwave systems. The book is divided into three parts, the first of which introduces readers to mm-wave wireless systems and power amplifiers. In turn, the second focuses on design principles and EDA concepts, while the third discusses future trends in power amplifier research. The book provides essential information on mm-wave power amplifier theory, as well as the implementation options and technologies involved in their effective design, equipping researchers, circuit designers and practicing engineers to design, model, analyze, test and implement high-performance, spectrally clean and energy-efficient mm-wave systems.
Mechanisms of buffer therapy resistance.
Bailey, Kate M; Wojtkowiak, Jonathan W; Cornnell, Heather H; Ribeiro, Maria C; Balagurunathan, Yoganand; Hashim, Arig Ibrahim; Gillies, Robert J
2014-04-01
Many studies have shown that the acidity of solid tumors contributes to local invasion and metastasis. Oral pH buffers can specifically neutralize the acidic pH of tumors and reduce the incidence of local invasion and metastatic formation in multiple murine models. However, this effect is not universal as we have previously observed that metastasis is not inhibited by buffers in some tumor models, regardless of buffer used. B16-F10 (murine melanoma), LL/2 (murine lung) and HCT116 (human colon) tumors are resistant to treatment with lysine buffer therapy, whereas metastasis is potently inhibited by lysine buffers in MDA-MB-231 (human breast) and PC3M (human prostate) tumors. In the current work, we confirmed that sensitive cells utilized a pH-dependent mechanism for successful metastasis supported by a highly glycolytic phenotype that acidifies the local tumor microenvironment resulting in morphological changes. In contrast, buffer-resistant cell lines exhibited a pH-independent metastatic mechanism involving constitutive secretion of matrix degrading proteases without elevated glycolysis. These results have identified two distinct mechanisms of experimental metastasis, one of which is pH-dependent (buffer therapy sensitive cells) and one which is pH-independent (buffer therapy resistant cells). Further characterization of these models has potential for therapeutic benefit. Copyright © 2014 Neoplasia Press, Inc. Published by Elsevier Inc. All rights reserved.
Yang, Shengchao; Ye, Fanggui; Zhang, Cong; Shen, Shufen; Zhao, Shulin
2015-04-21
In this study, HKUST-1 was synthesized in situ on the porous polymer monolith as the stationary phase for capillary liquid chromatography (cLC). The unique carboxyl functionalized poly(methacrylic acid-co-ethylene dimethacrylate) (poly(MAA-co-EDMA)) monolith was used as a support to directly grow HKUST-1 by a controlled layer-by-layer self-assembly strategy. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry, and Fourier transform infrared spectroscopy of the resulting HKUST-1-poly(MAA-co-EDMA) monoliths indicated that HKUST-1 was successfully grafted onto the pore surface of the poly(MAA-co-EDMA) monolith. The column performance of HKUST-1-poly(MAA-co-EDMA) monoliths for the separation of various small molecules, such as benzenediols, xylenes, ethylbenzenes, and styrenes, was evaluated. The chromatographic performance was found to improve with increasing HKUST-1 density, and the column efficiencies and resolutions of HKUST-1-poly(MAA-co-EDMA) monoliths were 18 320-19 890 plates m(-1) and 1.62-6.42, respectively, for benzenediols. The HKUST-1-poly(MAA-co-EDMA) monolith displayed enhanced resolution for the separation of positional isomers when compared to the traditional C18 and HKUST-1 incorporated polymer monoliths. Hydrophobic, π-π, and hydrogen bonding interactions within the HKUST-1-poly(MAA-co-EDMA) monolith were observed in the separation of small molecules. The results showed that the HKUST-1-poly(MAA-co-EDMA) monoliths are promising stationary phases for cLC.
Oscillators and operational amplifiers
Lindberg, Erik
2005-01-01
A generalized approach to the design of oscillators using operational amplifiers as active elements is presented. A piecewise-linear model of the amplifier is used so that it make sense to investigate the eigenvalues of the Jacobian of the differential equations. The characteristic equation of the general circuit is derived. The dynamic nonlinear transfer characteristic of the amplifier is investigated. Examples of negative resistance oscillators are discussed.
Several fluidic tuned AC Amplifiers were designed and tested. Interstage tuning and feedback designs are considered. Good results were obtained...corresponding Q’s as high as 12. Element designs and test results of one, two, and three stage amplifiers are presented. AC Modulated Carrier Systems
A video Hartmann wavefront diagnostic that incorporates a monolithic microlens array
International Nuclear Information System (INIS)
Toeppen, J.S.; Bliss, E.S.; Long, T.W.; Salmon, J.T.
1991-07-01
we have developed a video Hartmann wavefront sensor that incorporates a monolithic array of microlenses as the focusing elements. The sensor uses a monolithic array of photofabricated lenslets. Combined with a video processor, this system reveals local gradients of the wavefront at a video frame rate of 30 Hz. Higher bandwidth is easily attainable with a camera and video processor that have faster frame rates. When used with a temporal filter, the reconstructed wavefront error is less than 1/10th wave
Advanced digital modulation: Communication techniques and monolithic GaAs technology
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.
Seneviratne, Sashieka
With the growth of smart phones, the demand for more broadband, data centric technologies are being driven higher. As mobile operators worldwide plan and deploy 4th generation (4G) networks such as LTE to support the relentless growth in mobile data demand, the need for strategically positioned pico-sized cellular base stations known as 'pico-cells' are gaining traction. In addition to having to design a transceiver in a much compact footprint, pico-cells must still face the technical challenges presented by the new 4G systems, such as reduced power consumptions and linear amplification of the signals. The RF power amplifier (PA) that amplifies the output signals of 4G pico-cell systems face challenges to minimize size, achieve high average efficiencies and broader bandwidths while maintaining linearity and operating at higher frequencies. 4G standards as LTE use non-constant envelope modulation techniques with high peak to average ratios. Power amplifiers implemented in such applications are forced to operate at a backed off region from saturation. Therefore, in order to reduce power consumption, a design of a high efficiency PA that can maintain the efficiency for a wider range of radio frequency signals is required. The primary focus of this thesis is to enhance the efficiency of a compact RF amplifier suitable for a 4G pico-cell base station. For this aim, an integrated two way Doherty amplifier design in a compact 10mm x 11.5mm2 monolithic microwave integrated circuit using GaN device technology is presented. Using non-linear GaN HFETs models, the design achieves high effi-ciencies of over 50% at both back-off and peak power regions without compromising on the stringent linearity requirements of 4G LTE standards. This demonstrates a 17% increase in power added efficiency at 6 dB back off from peak power compared to conventional Class AB amplifier performance. Performance optimization techniques to select between high efficiency and high linearity operation are
Numerical simulation research on rolling process of monolithic nuclear fuel plate
International Nuclear Information System (INIS)
Wan Jibo; Kong Xiangzhe; Ding Shurong; Xu Hongbin; Huo Yongzhong
2015-01-01
For the strain-rate-dependent constitutive relation of zircaloy cladding in UMo monolithic nuclear fuel plates, the three-dimensional stress updating algorithm was derived out, and the corresponding VUMAT subroutine to define its constitutive relation was developed and validated; the finite element model was built to simulate the frame rolling process of UMo monolithic nuclear fuel plates; with the explicit dynamic finite element method, the evolution rules of the deformation and contact pressure during the rolling process within the composite slab were obtained and analyzed. The research results indicate that it is convenient and efficient to define the strain-rate- dependent constitutive relations of materials with the user-defined material subroutine VUMAT; the rolling-induced contact pressure between the fuel meat and the covers varies with time, and the maximum pressure exits at the symmetric plane along the plate width direction. This study supplies a foundation and a computation method for optimizing the processing parameters to manufacture UMo monolithic nuclear fuel plates. (authors)
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.
New requirements for buffer zones and sign posting contribute to soil fumigant mitigation and protection for workers and bystanders. The buffer provides distance between the pesticide application site and bystanders, reducing exposure risk.
International Nuclear Information System (INIS)
Li, Daxin; Yang, Zhihua; Jia, Dechang; Wang, Shengjin; Duan, Xiaoming; Zhu, Qishuai; Miao, Yang; Rao, Jiancun; Zhou, Yu
2017-01-01
Highlights: •The scale growth for all investigated monoliths at 1500 °C cannot be depicted by a linear or parabolic rate law. •The carbon-rich monoliths oxidize at 1500 °C according to a approximately linear weight loss equation. •The excessive carbon in SiBCN monoliths deteriorates the oxidation resistance. •The oxidation resistance stems from the characteristic oxide structures and increased oxidation resistance of BN(C). -- Abstract: The high temperature oxidation behavior of three SiBCN monoliths: carbon-lean SiBCN with substantial Si metal, carbon-moderate SiBCN and carbon-rich SiBCN with excessive carbon, was investigated at 1500 °C for times up to15 h. Scale growth for carbon-lean and −moderate monoliths at 1500 °C cannot be described by a linear or parabolic rate law, while the carbon-rich monoliths oxidize according to a approximately linear weight loss equation. The microstructures of the oxide scale compose of three distinct layers. The passivating layer of carbon and boron containing amorphous SiO 2 and increased oxidation resistance of BN(C) both benefit the oxidation resistance.
Monolithic Inorganic ZnO/GaN Semiconductors Heterojunction White Light-Emitting Diodes.
Jeong, Seonghoon; Oh, Seung Kyu; Ryou, Jae-Hyun; Ahn, Kwang-Soon; Song, Keun Man; Kim, Hyunsoo
2018-01-31
Monolithic light-emitting diodes (LEDs) that can generate white color at the one-chip level without the wavelength conversion through packaged phosphors or chip integration for photon recycling are of particular importance to produce compact, cost-competitive, and smart lighting sources. In this study, monolithic white LEDs were developed based on ZnO/GaN semiconductor heterojunctions. The electroluminescence (EL) wavelength of the ZnO/GaN heterojunction could be tuned by a post-thermal annealing process, causing the generation of an interfacial Ga 2 O 3 layer. Ultraviolet, violet-bluish, and greenish-yellow broad bands were observed from n-ZnO/p-GaN without an interfacial layer, whereas a strong greenish-yellow band emission was the only one observed from that with an interfacial layer. By controlled integration of ZnO/GaN heterojunctions with different postannealing conditions, monolithic white LED was demonstrated with color coordinates in the range (0.3534, 0.3710)-(0.4197, 0.4080) and color temperatures of 4778-3349 K in the Commission Internationale de l'Eclairage 1931 chromaticity diagram. Furthermore, the monolithic white LED produced approximately 2.1 times higher optical output power than a conventional ZnO/GaN heterojunction due to the carrier confinement effect at the Ga 2 O 3 /n-ZnO interface.
Energy Technology Data Exchange (ETDEWEB)
Do, Manh Huy [Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, Zhejiang (China); College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang (China); Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh (Viet Nam); Cheng, Dang-guo, E-mail: dgcheng@zju.edu.cn [College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang (China); Chen, Fengqiu [Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, Zhejiang (China); College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang (China); Zhan, Xiaoli [College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, Zhejiang (China)
2015-11-15
Although many strategies exist for fabricating hierarchical zeolite monolith, it is still challenging to synthesize pure hierarchical zeolite monolith with intracrystalline meso-/macropores and stability suitable for industrial application in a general and efficient process. Here we describe a simple quasi-solid gel crystallization route to prepare hierarchical self-standing ZSM-5 zeolite monolith via the use of Na{sup +} and OH{sup −} as counterions to modify the breaking and remaking of T–O–T (T = Si or Al) bonds. X-ray diffraction (XRD), scanning electron microcopy (SEM), transmission electron microscopy (TEM), laser scan confocal microscopy (LSCM), N{sub 2} adsorption–desorption, mercury porosimetry, solid-state nuclear magnetic resonance (NMR), and compression mechanical testing were applied to elucidate the structure and mechanical stability of the obtained monolith. The self-standing monolith is composed of self-interconnected meso-/macroporous MFI crystals with tunable intracrystalline meso-/macropores and possesses an unusually mechanical stability with a crushing strength of 5.01 MPa. Combined with controllable structure of the defect-free membrane layer on the monolith top, the self-standing zeolite monolith should widen their potential applications. - Highlights: • Hierarchical self-standing MFI zeolite monoliths were synthesized via a facile method. • Na{sup +} and OH{sup −} are used as counterions for breaking and remaking of T–O–T (T = Si or Al) bonds. • Hierarchical self-standing MFI zeolite monoliths result from zeolite crystal intergrowth. • Self-standing zeolite monolith has an excellent mechanical stability with tunable intracrystalline meso-/macropores.
International Nuclear Information System (INIS)
Wu Chia-Song; Chang Chien-Huang; Liu Hsing-Chung; Lin Tah-Yeong; Wu Hsien-Ming
2010-01-01
This investigation explores a low-noise amplifier (LNA) with a coplanar waveguide (CPW) structure, in which a two-stage amplifier is associated with a cascade schematic circuit, implemented in 0.15-μm GaAs pseudomorphic high electron mobility transistor (pHEMT) technology in a Ka-band (26.5-40.0 GHz) microwave monolithic integrated circuit (MMIC). The experimental results demonstrate that the proposed LNA has a peak gain of 12.53 dB at 30 GHz and a minimum noise figure of 3.3 dB at 29.5 GHz, when biased at a V ds of 2 V and a V gs of -0.6 V with a drain current of 16 mA in the circuit. The results show that the millimeter-wave LNA with coplanar waveguide structure has a higher gain and wider bandwidth than a conventional circuit. Finally, the overall LNA characterization exhibits high gain and low noise, indicating that the LNA has a compact circuit and favorable RF characteristics. The strong RF character exhibited by the LNA circuit can be used in millimeter-wave circuit applications. (semiconductor integrated circuits)
Fiber-based monolithic columns for liquid chromatography.
Ladisch, Michael; Zhang, Leyu
2016-10-01
Fiber-based monoliths for use in liquid chromatographic separations are defined by columns packed with aligned fibers, woven matrices, or contiguous fiber structures capable of achieving rapid separations of proteins, macromolecules, and low molecular weight components. A common denominator and motivating driver for this approach, first initiated 25 years ago, was reducing the cost of bioseparations in a manner that also reduced residence time of retained components while achieving a high ratio of mass to momentum transfer. This type of medium, when packed into a liquid chromatography column, minimized the fraction of stagnant liquid and resulted in a constant plate height for non-adsorbing species. The uncoupling of dispersion from eluent flow rate enabled the surface chemistry of the stationary phase to be considered separately from fluid transport phenomena and pointed to new ways to apply chemistry for the engineering of rapid bioseparations. This paper addresses developments and current research on fiber-based monoliths and explains how the various forms of this type of chromatographic stationary phase have potential to provide new tools for analytical and preparative scale separations. The different stationary phases are discussed, and a model that captures the observed constant plate height as a function of mobile phase velocity is reviewed. Methods that enable hydrodynamically stable fiber columns to be packed and operated over a range of mobile phase flow rates, together with the development of new fiber chemistries, are shown to provide columns that extend the versatility of liquid chromatography using monoliths, particularly at the preparative scale. Graphical Abstract Schematic representation of a sample mixture being separated by a rolled-stationary phase column, resulting separated peaks shown in the chromatogram.
Application of monolithic polycapillary focusing optics in MXRF
International Nuclear Information System (INIS)
Gao, N.; Ponomarev, I.; Xiao, Q.F.; Gibson, W.M.
1996-01-01
A monolithic polycapillary focusing optic, consisting of hundreds of thousands of small tapered glass capillaries, can collect a large solid angle of x rays from a point source and guide them through the capillaries by multiple total reflections to form an intense focused beam. Such a focused beam has many applications in microbeam x-ray fluorescence (MXRF) analysis. Two monolithic polycapillary focusing optics were tested and characterized in a MXRF set-up using a microfocusing x-ray source (50microm x 10microm). For the Cu K α line, the measured focal spot sizes of these optics were 105microm and 43microm Full-Width-Half-Maximum (FWHM), respectively. When the source was operated at 16W, the average Cu K α intensities over the focal spots were measured to be 2.4 x 10 4 photons/s/microm 2 and 8.9 x 10 4 photons/s/microm 2 , respectively. When the authors compared the monolithic optics to straight monocapillary optics (single channel capillary) with approximately the same output beam sizes, intensity gains of 16 and 44 were obtained. The optics were applied to the MXRF set-up to analyze trace elements in various samples and a Minimum Detection Limit (MDL) of about 2 pg was achieved for the transition elements (V, Cr, Mn, and Fe). The optics were also used to map the distributions of trace elements in various samples
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.
International Nuclear Information System (INIS)
Gershenson, M.
1989-01-01
A current amplifier design based on the principle of fluxon propagation in a multi-junction Exponential Flux Shuttle has been investigated. In this design, the critical current of the junction is increased exponentially and the SQUID inductance is a JJ (Josephson Junction) equivalent inductance. Current gain can be achieved by generating fluxons at the low end and dissipating them at the high end where the load is located. Advantages over other types of linear devices are discussed. Two parallel Exponential Flux Shuttles can be used to duplicate flux from a high inductance input coil t a low inductance output. Device performance of the two circuits are evaluated by computer simulation, noise performance is discussed
Rapid determination of amino acids in biological samples using a monolithic silica column.
Song, Yanting; Funatsu, Takashi; Tsunoda, Makoto
2012-05-01
A high-performance liquid chromatography method in which fluorescence detection is used for the simultaneous determination of 21 amino acids is proposed. Amino acids were derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) and then separated on a monolithic silica column (MonoClad C18-HS, 150 mm×3 mm i.d.). A mixture of 25 mM citrate buffer containing 25 mM sodium perchlorate (pH 5.5) and acetonitrile was used as the mobile phase. We found that the most significant factor in the separation was temperature, and a linear temperature gradient from 30 to 49°C was used to control the column temperature. The limits of detection and quantification for all amino acids ranged from 3.2 to 57.2 fmol and 10.8 to 191 fmol, respectively. The calibration curves for the NBD-amino acid had good linearity within the range of 40 fmol to 40 pmol when 6-aminocaproic acid was used as an internal standard. Using only conventional instruments, the 21 amino acids could be analyzed within 10 min. This method was found to be suitable for the quantification of the contents of amino acids in mouse plasma and adrenal gland samples.
A CMOS current-mode operational amplifier
DEFF Research Database (Denmark)
Kaulberg, Thomas
1993-01-01
current-mode feedback amplifier or a constant bandwidth in a transimpedance feedback amplifier. The amplifier is found to have a gain-bandwidth product of 3 MHz, an offset current of 0.8 μA (signal range ±700 μA), and a (theoretically) unlimited slew rate. The amplifier is realized in a standard CMOS 2......A fully differential-input, differential-output, current-mode operational amplifier (COA) is described. The amplifier utilizes three second-generation current conveyors (CCIIs) as the basic building blocks. It can be configured to provide either a constant gain-bandwidth product in a fully balanced...
Modeling of semiconductor optical amplifiers
DEFF Research Database (Denmark)
Mørk, Jesper; Bischoff, Svend; Berg, Tommy Winther
We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed.......We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed....
Ma, Shujuan; Zhang, Haiyang; Li, Ya; Li, Yanan; Zhang, Na; Ou, Junjie; Ye, Mingliang; Wei, Yinmao
2018-02-23
Although several approaches have been developed to fabricate hybrid monoliths, it would still take a few hours to finish the formation of monoliths. Herein, photo-initiated thiol-yne polymerization was first adopted to in situ fabricate hybrid monoliths within the confines of UV-transparent fused-silica capillary. A silicon-containing diyne (1,3-diethynyltetramethyl-disiloxane, DYDS) was copolymerized with three multithiols, 1,6-hexanedithiol, trimethylolpropane tris(3-mercaptopropionate) and pentaerythriol tetrakis(3-mercaptopropionate), by using a binary porogenic system of diethylene glycol diethyl ether (DEGDE)/poly(ethylene glycol) (PEG200) within 10 min. Several characterizations of three hybrid monoliths (assigned as I, II and III, respectively) were performed. The results showed that these hybrid monoliths possessed bicontinuous porous structure, which was remarkably different from that via typical free-radical polymerization. The highest column efficiency of 76,000 plates per meter for butylbenzene was obtained on the column I in reversed-phase liquid chromatography (RPLC). It was observed that the efficiencies for strong-retained butylbenzene were almost close to those of weak-retained benzene, indicating a retention-independent efficient performance of small molecules on hybrid column I. The surface area of this hybrid monolith was very small in the dry state (less than 10.0 m 2 /g), and the chromatographic behavior of hybrid monolithic columns would be possibly explained by radical-mediated step-growth process of thiol-yne polymerization. Finally, the column I was applied for separation of BSA tryptic digest by cLC-MS/MS, indicating satisfactory separation ability for complicated samples. Copyright © 2018 Elsevier B.V. All rights reserved.
HIGH AVERAGE POWER OPTICAL FEL AMPLIFIERS
International Nuclear Information System (INIS)
2005-01-01
Historically, the first demonstration of the optical FEL was in an amplifier configuration at Stanford University [l]. There were other notable instances of amplifying a seed laser, such as the LLNL PALADIN amplifier [2] and the BNL ATF High-Gain Harmonic Generation FEL [3]. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance FEL's with average power of 100 kW or more. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting Energy Recovery Linacs (ERL) combine well with the high-gain FEL amplifier to produce unprecedented average power FELs. This combination has a number of advantages. In particular, we show that for a given FEL power, an FEL amplifier can introduce lower energy spread in the beam as compared to a traditional oscillator. This properly gives the ERL based FEL amplifier a great wall-plug to optical power efficiency advantage. The optics for an amplifier is simple and compact. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Linac which is under construction at Brookhaven National Laboratory's Collider-Accelerator Department
Lin, Hui; Zhang, Zhenbin; Dong, Jing; Liu, Zhongshan; Ou, Junjie; Zou, Hanfa
2013-09-01
A new organic-inorganic hybrid monolith was prepared by the ring-opening polymerization of octaglycidyldimethylsilyl polyhedral oligomeric silsesquioxane (POSS) with 1,4-butanediamine (BDA) using 1-propanol, 1,4-butanediol, and PEG 10,000 as a porogenic system. Benefiting from the moderate phase separation process, the resulting poly(POSS-co-BDA) hybrid monolith possessed a uniform microstructure and exhibited excellent performance in chromatographic applications. Neutral, acidic, and basic compounds were successfully separated on the hybrid monolith in capillary LC (cLC), and high column efficiencies were achieved in all of the separations. In addition, as the amino groups could generate a strong EOF, the hybrid monolith was also applied in CEC for the separation of neutral and polar compounds, and a satisfactory performance was obtained. These results demonstrate that the poly(POSS-co-BDA) hybrid monolith is a good separation media in chromatographic separations of various types of compounds by both cLC and CEC. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Microchip-based monolithic column for high performance liquid chromatography
National Aeronautics and Space Administration — We have developed microchip based monolithic columns that can be used for liquid chromatography of small organic molecules, as well as, macromolecules such as...
Kurdi, Said El; Muaileq, Dina Abu; Alhazmi, Hassan A; Bratty, Mohammed Al; Deeb, Sami El
2017-06-27
HPLC stationary phases of monolithic and fused core type can be used to achieve fast chromatographic separation as an alternative to UPLC. In this study, monolithic and fused core stationary phases are compared for fast separation of four fat-soluble vitamins. Three new methods on the first and second generation monolithic silica RP-18e columns and a fused core pentafluoro-phenyl propyl column were developed. Application of three fused core columns offered comparable separations of retinyl palmitate, DL-α-tocopheryl acetate, cholecalciferol and menadione in terms of elution speed and separation efficiency. Separation was achieved in approx. 5 min with good resolution (Rs > 5) and precision (RSD ≤ 0.6 %). Monolithic columns showed, however, a higher number of theoretical plates, better precision and lower column backpressure than the fused core column. The three developed methods were successfully applied to separate and quantitate fat-soluble vitamins in commercial products.
Electrospun amplified fiber optics.
Morello, Giovanni; Camposeo, Andrea; Moffa, Maria; Pisignano, Dario
2015-03-11
All-optical signal processing is the focus of much research aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for efficient signal transmission. However, the complex fabrication methods involving high-temperature processes performed in a highly pure environment slow the fabrication process and make amplified components expensive with respect to an ideal, high-throughput, room temperature production. Here, we report on near-infrared polymer fiber amplifiers working over a band of ∼20 nm. The fibers are cheap, spun with a process entirely carried out at room temperature, and shown to have amplified spontaneous emission with good gain coefficients and low levels of optical losses (a few cm(-1)). The amplification process is favored by high fiber quality and low self-absorption. The found performance metrics appear to be suitable for short-distance operations, and the large variety of commercially available doping dyes might allow for effective multiwavelength operations by electrospun amplified fiber optics.
Study of monolithic prestressed reinforced concrete overhead road.
Directory of Open Access Journals (Sweden)
Ya.I. Kovalchyk
2011-12-01
Full Text Available Results of inspection and testing of monolithic prestressed reinforced concrete road trestle built in Kyiv are considered. The analysis of the gained results has shown that parametres correspond to the requirements of current standards on design of bridges.
Monolithic all-PM femtosecond Yb-doped fiber laser using photonic bandgap fibers
DEFF Research Database (Denmark)
Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry
2009-01-01
We present a monolithic Yb fiber laser, dispersion managed by an all-solid photonic bandgap fiber, and pulse compressed in a hollow-core photonic crystal fiber. The laser delivers 9 nJ, 275-fs long pulses at 1035 nm.......We present a monolithic Yb fiber laser, dispersion managed by an all-solid photonic bandgap fiber, and pulse compressed in a hollow-core photonic crystal fiber. The laser delivers 9 nJ, 275-fs long pulses at 1035 nm....
Low frequency seismic noise acquisition and analysis with tunable monolithic horizontal sensors
Acernese, Fausto; De Rosa, Rosario; Giordano, Gerardo; Romano, Rocco; Vilasi, Silvia; Barone, Fabrizio
2011-04-01
In this paper we describe the scientific data recorded mechanical monolithic horizontal sensor prototypes located in the Gran Sasso Laboratory of the INFN. The mechanical monolithic sensors, developed at the University of Salerno, are placed, in thermally insulating enclosures, onto concrete slabs connected to the bedrock. The main goal of this experiment is to characterize seismically the sites in the frequency band 10-4 ÷ 10Hz and to get all the necessary information to optimize the sensor.
Guo, Jialiang; Xiao, Yuan; Lin, Yuanjing; Zhang, Qiaoxuan; Chang, Yiqun; Crommen, Jacques; Jiang, Zhengjin
2016-05-15
In order to investigate the effect of the linking spacer on the enantioseparation ability of β-cyclodextrin (β-CD) functionalized polymeric monoliths, three β-CD-functionalized organic polymeric monoliths with different spacer lengths were prepared by using three amino-β-CDs, i.e. mono-6-amino-6-deoxy-β-CD, mono-6-ethylenediamine-6-deoxy-β-CD, mono-6-hexamethylenediamine-6-deoxy-β-CD, as starting materials. These amino-β-CDs reacted with glycidyl methacrylate to produce functional monomers which were then copolymerized with ethylene dimethacrylate. The enantioseparation ability of the three monoliths was evaluated using 14 chiral acidic compounds, including mandelic acid derivatives, nonsteroidal anti-inflammatory drugs, N-derivatized amino acids, and chiral herbicides under optimum chromatographic conditions. Notably, the poly(GMA-NH2-β-CD-co-EDMA) column provides higher enantioresolution and enantioselectivity than the poly(GMA-EDA-β-CD-co-EDMA) and poly(GMA-HDA-β-CD-co-EDMA) columns for most tested chiral analytes. Furthermore, the enantioseparation performance of triazole-linker containing monoliths was compared to that of ethylenediamine-linker containing monoliths. The results indicate that the enantioselectivity of β-CD monolithic columns is strongly related to the length and type of spacer tethering β-CD to the polymeric support. Copyright © 2016 Elsevier B.V. All rights reserved.
Signature-based store checking buffer
Sridharan, Vilas; Gurumurthi, Sudhanva
2015-06-02
A system and method for optimizing redundant output verification, are provided. A hardware-based store fingerprint buffer receives multiple instances of output from multiple instances of computation. The store fingerprint buffer generates a signature from the content included in the multiple instances of output. When a barrier is reached, the store fingerprint buffer uses the signature to verify the content is error-free.
International Nuclear Information System (INIS)
Ratti, L.; Manghisoni, M.; Re, V.; Speziali, V.; Traversi, G.; Bettarini, S.; Calderini, G.; Cenci, R.; Giorgi, M.; Forti, F.; Morsani, F.; Rizzo, G.
2006-01-01
This work studies the feasibility of a new implementation of CMOS monolithic active pixel sensors (MAPS) for applications to charged particle tracking. As compared to standard three MOSFET MAPS, where the charge signal is readout by a source follower, the proposed front-end scheme relies upon a charge sensitive amplifier (CSA), embedded in the elementary pixel cell, to perform charge-to-voltage conversion. The area required for the integration of the front-end electronics is mostly provided by the collecting electrode, which consists of a deep n-type diffusion, available as a shielding frame for n-channel devices in deep submicron, triple well CMOS technologies. Based on the above concept, a chip, which includes several test structures differing in the sensitive element area, has been fabricated in a 0.13μm CMOS process. In this paper, the criteria underlying the design of the pixel level analog processor will be presented, together with some preliminary experimental results demonstrating the feasibility of the proposed approach
DEFF Research Database (Denmark)
Lafleur, Josiane P; Senkbeil, Silja; Novotny, Jakub
2015-01-01
A novel, rapid and simple method for the preparation of emulsion-templated monoliths in microfluidic channels based on thiol-ene chemistry is presented. The method allows monolith synthesis and anchoring inside thiol-ene microchannels in a single photoinitiated step. Characterization by scanning...... electron microscopy showed that the methanol-based emulsion templating process resulted in a network of highly interconnected and regular thiol-ene beads anchored solidly inside thiol-ene microchannels. Surface area measurements indicate that the monoliths are macroporous, with no or little micro...
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.
International Nuclear Information System (INIS)
Lepetit, J.; Poussier, E.
1984-01-01
This amplifier comprises an inverter transformer, the primary circuit of which receives a pulse and the secondary circuit of which is connected to several amplifying elements in parallel. The inverter transformer is made of coaxial cable segments winded around a magnetic torus; the cable cores connected in series constitute the primary circuit and the braiding of cables, connected in parallel, are the secondary circuit. The transformer comprises, besides, delay lines in series with each braiding of the secondary circuit, these ones are such that pulses issued from each braiding arrive together to the secondary circuit connectors. This invention applies, noticeably in the case of a high voltage amplifier, to the control of deflection blocks of particles used in medicine or in particle accelerators [fr
Yun, Ruida; Sthalekar, Chirag; Joyner, Valencia M
2011-01-01
This paper presents the design and measurement results of two avalanche photodiode structures (APDs) and a novel frequency-mixing transimpedance amplifier (TIA), which are key building blocks towards a monolithically integrated optical sensor front end for near-infrared (NIR) spectroscopy applications. Two different APD structures are fabricated in an unmodified 0.18 \\im CMOS process, one with a shallow trench isolation (STI) guard ring and the other with a P-well guard ring. The APDs are characterized in linear mode. The STI bounded APD demonstrates better performance and exhibits 3.78 A/W responsivity at a wavelength of 690 nm and bias voltage of 10.55 V. The frequency-mixing TIA (FM-TIA) employs a T-feedback network incorporating gate-controlled transistors for resistance modulation, enabling the simultaneous down-conversion and amplification of the high frequency modulated photodiode (PD) current. The TIA achieves 92 dS Ω conversion gain with 0.5 V modulating voltage. The measured IIP(3) is 10.6/M. The amplifier together with the 50 Ω output buffer draws 23 mA from a1.8 V power supply.
International Nuclear Information System (INIS)
Radeka, V.; Rescia, S.; Rehn, L.A.; Manfredi, P.F.; Speziali, V.
1991-11-01
The outstanding noise and radiation hardness characteristics of epitaxial-channel junction field-effect transistors (JFET) suggest that a monolithic preamplifier based upon them may be able to meet the strict specifications for calorimetry at high luminosity colliders. Results obtained so far with a buried layer planar technology, among them an entire monolithic charge-sensitive preamplifier, are described
A fluidic/pneumatic interface amplifier
Limbert, D. E.; Kegel, T. M.
The development of a low cost, reliable, linear pressure amplifier to interface Laminar Proportional Amplifiers (LPA) to pneumatic controllers is presented. The amplifier consists of an LPA input stage and an output stage consisting of a venturi in series with a bellows nozzle valve. The LPA output drives the bellows nozzle valve thereby altering the flowrate through the venturi. The pressure within the venturi throat region, which is the amplifier output, changes with the flowrate. Non-linear characteristics, due to supersonic flow within the venturi, are altered through the use of feedback to the LPA input. A computer based model, to aid in optimizing the amplifier design, is developed. This model incorporates the effects of shock waves and boundary layers within the venturi. Good correspondence between the model and an experimental prototype is shown.
Rubin, Mark
2017-01-01
The present research investigated different types of social class identification as moderators of the negative relation between social class and mental health problems. Psychology undergraduates (N = 355) completed an online survey that included measures of social class, mental health and well-being, and three aspects of social class identification: importance of identity, salience of identity, and perceived self-class similarity. Perceived self-class similarity buffered the negative associat...
Directory of Open Access Journals (Sweden)
Kurdi Said El
2017-06-01
Full Text Available HPLC stationary phases of monolithic and fused core type can be used to achieve fast chromatographic separation as an alternative to UPLC. In this study, monolithic and fused core stationary phases are compared for fast separation of four fat-soluble vitamins. Three new methods on the first and second generation monolithic silica RP-18e columns and a fused core pentafluoro-phenyl propyl column were developed. Application of three fused core columns offered comparable separations of retinyl palmitate, DL-α-tocopheryl acetate, cholecalciferol and menadione in terms of elution speed and separation efficiency. Separation was achieved in approx. 5 min with good resolution (Rs > 5 and precision (RSD ≤ 0.6 %. Monolithic columns showed, however, a higher number of theoretical plates, better precision and lower column backpressure than the fused core column. The three developed methods were successfully applied to separate and quantitate fat-soluble vitamins in commercial products.
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. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Amplifier for nuclear spectrometry
International Nuclear Information System (INIS)
Suarez Canner, E.
1996-01-01
The spectroscopy amplifier model AE-020 is designed to adjust suitable the pulses coming from nuclear radiation detectors. Due to is capacity and specifications, the amplifier can be used together with high and medium resolution spectroscopy system
Tilma, B.W.; Jiao, Y.; Kotani, J.; Smalbrugge, B.; Ambrosius, H.P.M.M.; Thijs, P.J.A.; Leijtens, X.J.M.; Nötzel, R.; Smit, M.K.; Bente, E.A.J.M.
2012-01-01
In this paper we present the design and characterization of a monolithically integrated tunable laser for optical coherence tomography in medicine. This laser is the first monolithic photonic integrated circuit containing quantum-dot amplifiers, phase modulators and passive components. We
Li, Qianjin; Liu, Zhen
2015-01-01
Boronate affinity monolithic columns have been developed into an important means for the selective recognition and capture of cis-diol-containing biomolecules, such as glycoproteins, nucleosides and saccharides. The ligands of boronic acids are playing an important role in boronate affinity monolithic columns. Although several boronate affinity monoliths with high affinity toward cis-diol-containing biomolecules have been reported, only few publications are focused on their detailed procedures for preparation and characterization. This chapter describes in detail the preparation and characterization of a boronate affinity monolithic column applying 2,4-difluoro-3-formyl-phenylboronic acid (DFFPBA) as a ligand. The DFFPBA-functionalized monolithic column not only exhibited an ultrahigh boronate affinity toward cis-diol-containing biomolecules, but also showed great potential for the selective enrichment of cis-diol-containing biomolecules in real samples.
Singh, Gurpreet; Singh, Maninder Lal
2015-08-01
A new four wave mixing (FWM) model for an optical network with amplifiers and a comparative analysis among three proposed amplifiers placement techniques have been presented in this paper. The FWM model is validated with the experimental measured data. The novelty of this model is its uniqueness that on direct substitutions of network parameters like length, it works even for unequal inter amplifier separations. The novelty of the analysis done among three schemes is that it presents fair choice of amplifiers placement methods for varied total system length. The appropriateness of these three schemes has been analyzed on the basis of critical system length, critical number of amplifiers and critical bit error rate (10-9) in presence of four wave mixing (FWM) and amplified spontaneous emission noise (ASE). The implementation of analysis done has been given with the help of an example of a regenerative metropolitan area network (MAN). The results suggest that the decreasing fiber section scheme should be avoided for placements of amplifiers and schemes IUFS and EFS shows their importance interchangeably for different set of parameters.
Semiconductor quantum-dot lasers and amplifiers
DEFF Research Database (Denmark)
Hvam, Jørn Märcher; Borri, Paola; Ledentsov, N. N.
2002-01-01
-power surface emitting VCSELs. We investigated the ultrafast dynamics of quantum-dot semiconductor optical amplifiers. The dephasing time at room temperature of the ground-state transition in semiconductor quantum dots is around 250 fs in an unbiased amplifier, decreasing to below 50 fs when the amplifier...... is biased to positive net gain. We have further measured gain recovery times in quantum dot amplifiers that are significantly lower than in bulk and quantum-well semiconductor optical amplifiers. This is promising for future demonstration of quantum dot devices with high modulation bandwidth...
NIF/LMJ prototype amplifier mechanical design
International Nuclear Information System (INIS)
Horvath, J.
1996-10-01
Amplifier prototypes for the National Ignition Facility and the Laser Megajoule will be tested at Lawrence Livermore National Laboratory. The prototype amplifier, which is an ensemble of modules from LLNL and Centre d'Etudes de Limeil-Valenton, is cassette-based with bottom access for maintenance. A sealed maintenance transfer vehicle which moves optical cassettes between the amplifier and the assembly cleanroom, and a vacuum gripper which holds laser slabs during cassette assembly will also be tested. The prototype amplifier will be used to verify amplifier optical performance, thermal recovery time, and cleanliness of mechanical operations
A low-voltage sense amplifier with two-stage operational amplifier clamping for flash memory
Guo, Jiarong
2017-04-01
A low-voltage sense amplifier with reference current generator utilizing two-stage operational amplifier clamp structure for flash memory is presented in this paper, capable of operating with minimum supply voltage at 1 V. A new reference current generation circuit composed of a reference cell and a two-stage operational amplifier clamping the drain pole of the reference cell is used to generate the reference current, which avoids the threshold limitation caused by current mirror transistor in the traditional sense amplifier. A novel reference voltage generation circuit using dummy bit-line structure without pull-down current is also adopted, which not only improves the sense window enhancing read precision but also saves power consumption. The sense amplifier was implemented in a flash realized in 90 nm flash technology. Experimental results show the access time is 14.7 ns with power supply of 1.2 V and slow corner at 125 °C. Project supported by the National Natural Science Fundation of China (No. 61376028).
Material Engineering for Monolithic Semiconductor Mode-Locked Lasers
DEFF Research Database (Denmark)
Kulkova, Irina
This thesis is devoted to the materials engineering for semiconductor monolithic passively mode-locked lasers (MLLs) as a compact energy-efficient source of ultrashort optical pulses. Up to the present day, the achievement of low-noise sub-picosecond pulse generation has remained a challenge...
International Nuclear Information System (INIS)
Horvath, J. A.
1998-01-01
Mechanical assembly and maintenance of the prototype National Ignition Facility amplifiers in the Amplifier Module Prototype Laboratory (AMPLAB) at Lawrence Livermore National Laboratory requires specialized equipment designed to manipulate large and delicate amplifier components in a safe and clean manner. Observations made during the operation of this assembly and maintenance equipment in AMPLAB provide design guidance for similar tools being built for the National Ignition Facility. Fixtures used for amplifier frame installation, laser slab and flashlamp cassette assembly, transport, and installation, and in-situ blastshield exchange are presented. Examples include a vacuum slab gripper, slab handling clean crane, slab cassette assembly fixture, sealed transport vehicle for slab cassette movement between the cleanroom and amplifier, slab cassette transfer fixture between the cleanroom and transport vehicle, and equipment needed for frame assembly unit, blastshield, an d flashlamp cassette installation and removal. The use of these tools for amplifier assembly, system reconfiguration, reflector replacement, and recovery from an abnormal occurrence such as a flashlamp explosion is described. Observations are made on the design and operation of these tools and their contribution to the final design
Individual optimization of InAlGaAsP-InP sections for 1.55-μm passively mode-locked lasers
DEFF Research Database (Denmark)
Kulkova, Irina; Larsson, David; Semenova, Elizaveta
2012-01-01
We present integrated single QW semiconductor optical amplifier and MQW electroabsorber modulator based on InAlGaAsP-InP materials for application in a monolithic mode-locked laser. Optimized structures with high-quality butt-joint interfaces are demonstrated.......We present integrated single QW semiconductor optical amplifier and MQW electroabsorber modulator based on InAlGaAsP-InP materials for application in a monolithic mode-locked laser. Optimized structures with high-quality butt-joint interfaces are demonstrated....
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.
Monolithic Parallel Tandem Organic Photovoltaic Cell with Transparent Carbon Nanotube Interlayer
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.
Developing suitable buffers to capture transport cycling behavior
DEFF Research Database (Denmark)
Madsen, Thomas; Schipperijn, Jasper; Christiansen, Lars Breum
2014-01-01
units (e.g., home-buffer-based neighborhoods) are not necessarily representative for environmental exposure. An increased understanding of appropriate neighborhoods is needed. GPS cycling tracks from 78 participants for 7 days form the basis for the development and testing of different neighborhood...... buffers for transport cycling. The percentage of GPS points per square meter was used as indicator of the effectiveness of a series of different buffer types, including home-based network buffers, shortest route to city center buffers, and city center-directed ellipse-shaped buffers. The results show...... center-directed ellipse-shaped buffers yielded better results than traditional home-based network buffer types. The ellipse-shaped buffer types could therefore be considered an alternative to more traditional buffers or administrative units in future studies of transport cycling behavior....
RESEARCH NEEDS IN RIPARIAN BUFFER RESTORATION
Riparian buffer restorations are used as management tools to produce favorable water quality impacts; moreover, the basis for riparian buffers as an instrument of water quality restoration rests on a relatively firm foundation. However, the extent to which buffers can restore rip...
Design for an 8 Meter Monolithic UV/OIR Space Telescope
Stahl, H. Philip; Postman, Marc; Hornsby, Linda; Hopkins, Randall; Mosier, Gary E.; Pasquale, Bert A.; Arnold, William R.
2009-01-01
ATLAST-8 is an 8-meter monolithic UV/optical/NIR space observatory to be placed in orbit at Sun-Earth L2 by NASA's planned Ares V cargo launch vehicle. The ATLAST-8 will yield fundamental astronomical breakthroughs. The mission concept utilizes two enabling technologies: planned Ares-V launch vehicle (scheduled for 2019) and autonomous rendezvous and docking (AR&D). The unprecedented Ares-V payload and mass capacity enables the use of a massive, monolithic, thin-meniscus primary mirror - similar to a VLT or Subaru. Furthermore, it enables simple robust design rules to mitigate cost, schedule and performance risk. AR&D enables on-orbit servicing, extending mission life and enhancing science return.
Directory of Open Access Journals (Sweden)
Agnieszka Ciemięga
2017-08-01
Full Text Available The performance of monolithic silica microreactors activated with sulphonic acid groups and a packed bed reactor with Amberlyst 15 resin were compared in the esterification of acetic acid with n-butanol. The monolithic microreactors were made of single silica rods with complex pore architecture, differing in the size of mesopores, and in particular, flow-through macropores which significantly affected the flow characteristic of the continuous system. The highest ester productivity of 105.2 mol·molH+−1·h−1 was achieved in microreactor M1 with the largest porosity, characterized by a total pore volume of 4 cm3·g−1, mesopores with 20 nm diameter, and large flow-through macropores 30–50 μm in size. The strong impact of the permeability of the monoliths on a reaction kinetics was shown.
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.
Buffer sizing for multi-hop networks
Shihada, Basem
2014-01-28
A cumulative buffer may be defined for an interference domain in a wireless mesh network and distributed among nodes in the network to maintain or improve capacity utilization of network resources in the interference domain without increasing packet queuing delay times. When an interference domain having communications links sharing resources in a network is identified, a cumulative buffer size is calculated. The cumulative buffer may be distributed among buffers in each node of the interference domain according to a simple division or according to a cost function taking into account a distance of the communications link from the source and destination. The network may be monitored and the cumulative buffer size recalculated and redistributed when the network conditions change.
Pitris, St.; Vagionas, Ch.; Kanellos, G. T.; Kisacik, R.; Tekin, T.; Broeke, R.; Pleros, N.
2016-03-01
At the dawning of the exaflop era, High Performance Computers are foreseen to exploit integrated all-optical elements, to overcome the speed limitations imposed by electronic counterparts. Drawing from the well-known Memory Wall limitation, imposing a performance gap between processor and memory speeds, research has focused on developing ultra-fast latching devices and all-optical memory elements capable of delivering buffering and switching functionalities at unprecedented bit-rates. Following the master-slave configuration of electronic Flip-Flops, coupled SOA-MZI based switches have been theoretically investigated to exceed 40 Gb/s operation, provided a short coupling waveguide. However, this flip-flop architecture has been only hybridly integrated with silica-on-silicon integration technology exhibiting a total footprint of 45x12 mm2 and intra-Flip-Flop coupling waveguide of 2.5cm, limited at 5 Gb/s operation. Monolithic integration offers the possibility to fabricate multiple active and passive photonic components on a single chip at a close proximity towards, bearing promises for fast all-optical memories. Here, we present for the first time a monolithically integrated all-optical SR Flip-Flop with coupled master-slave SOA-MZI switches. The photonic chip is integrated on a 6x2 mm2 die as a part of a multi-project wafer run using library based components of a generic InP platform, fiber-pigtailed and fully packaged on a temperature controlled ceramic submount module with electrical contacts. The intra Flip-Flop coupling waveguide is 5 mm long, reducing the total footprint by two orders of magnitude. Successful flip flop functionality is evaluated at 10 Gb/s with clear open eye diagram, achieving error free operation with a power penalty of 4dB.
Monolithic pixels on moderate resistivity substrate and sparsifying readout architecture
International Nuclear Information System (INIS)
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.
2013-01-01
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 55 Fe 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
Energy Technology Data Exchange (ETDEWEB)
Lin, Shu-Ling; Wang, Chih-Chieh; Fuh, Ming-Ren, E-mail: msfuh@scu.edu.tw
2016-10-05
In this study, divinylbenzene (DVB) was used as the cross-linker to prepare alkyl methacrylate (AlMA) monoliths for incorporating π-π interactions between the aromatic analytes and AlMA-DVB monolithic stationary phases in capillary LC analysis. Various AlMA/DVB ratios were investigated to prepare a series of 30% AlMA-DVB monolithic stationary phases in fused-silica capillaries (250-μm i.d.). The physical properties (such as porosity, permeability, and column efficiency) of the synthesized AlMA-DVB monolithic columns were investigated for characterization. Isocratic elution of phenol derivatives was first employed to evaluate the suitability of the prepared AlMA-DVB columns for small molecule separation. The run-to-run (0.16–1.20%, RSD; n = 3) and column-to-column (0.26–2.95%, RSD; n = 3) repeatabilities on retention times were also examined using the selected AlMA-DVB monolithic columns. The π-π interactions between the aromatic ring and the DVB-based stationary phase offered better recognition on polar analytes with aromatic moieties, which resulted in better separation resolution of aromatic analytes on the AlMA-DVB monolithic columns. In order to demonstrate the capability of potential environmental and/or food safety applications, eight phenylurea herbicides with single benzene ring and seven sulfonamide antibiotics with polyaromatic moieties were analyzed using the selected AlMA-DVB monolithic columns. - Highlights: • First investigation on chromatographic selectivity of AlMA-DVB monolithic columns. • Good run-to-run/column-to-column repeatability (<3%) on AlMA-DVB monolithic columns. • Efficient separation of phenylurea herbicides and sulfonamides on AlMA-DVB columns.
Monolithic microwave integrated circuit with integral array antenna
International Nuclear Information System (INIS)
Stockton, R.J.; Munson, R.E.
1984-01-01
A monolithic microwave integrated circuit including an integral array antenna. The system includes radiating elements, feed network, phasing network, active and/or passive semiconductor devices, digital logic interface circuits and a microcomputer controller simultaneously incorporated on a single substrate by means of a controlled fabrication process sequence
Preparation and characterization of Au/CeO{sub 2}-Al{sub 2}O{sub 3} monoliths
Energy Technology Data Exchange (ETDEWEB)
Gawel, Bartlomiej; Lambrechts, Kalle [Ugelstad Laboratory, Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway); Oye, Gisle, E-mail: gisle.oye@chemeng.ntnu.no [Ugelstad Laboratory, Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim (Norway)
2012-05-15
Highlights: Black-Right-Pointing-Pointer A facile method for preparing Au/CeO{sub 2}-Al{sub 2}O{sub 3} monoliths with hierarchical porosity. Black-Right-Pointing-Pointer Continuous-flow testing of the monoliths in liquid-phase oxidation of glucose. Black-Right-Pointing-Pointer Increased catalytic activity in the presence of cerium oxide (stirred-batch tests). - Abstract: Porous CeO{sub 2}-Al{sub 2}O{sub 3} monoliths with hierarchical pore structure were prepared by mixing boehmite particles with solutions containing different amounts of cerium chloride and aluminum nitrate. The monoliths were functionalized with gold nanoparticles using the incipient wetness method. The resulting materials were characterized by X-ray diffraction, nitrogen sorption, mercury porosimetry, UV-vis spectroscopy and transmission electron microscopy. The catalysts were tested in liquid phase glucose oxidation, comparing continuously stirred batch reactor and continuous-flow fix-bed reactor setups.
Moyna, Áine; Connolly, Damian; Nesterenko, Ekaterina; Nesterenko, Pavel N; Paull, Brett
2013-03-01
Lauryl methacrylate-co-ethylene dimethacrylate monoliths were polymerised within fused silica capillaries and subsequently photo-grafted with varying amounts of glycidyl methacrylate (GMA). The grafted monoliths were then further modified with iminodiacetic acid (IDA), resulting in a range of chelating ion-exchange monoliths of increasing capacity. The IDA functional groups were attached via ring opening of the epoxy group on the poly(GMA) structure. Increasing the amount of attached poly(GMA), via photo-grafting with increasing concentrations of GMA, from 15 to 35%, resulted in a proportional and controlled increase in the complexation capacity of the chelating monoliths. Scanning capacitively coupled contactless conductivity detection (sC(4)D) was used to characterise and verify homogenous distribution of the chelating ligand along the length of the capillaries non-invasively. Chelation ion chromatographic separations of selected transition and heavy metals were carried out, with retention factor data proportional to the concentration of grafted poly(GMA). Average peak efficiencies of close to 5,000 N/m were achieved, with the isocratic separation of Na, Mg(II), Mn(II), Co(II), Cd(II) and Zn(II) possible on a 250-mm-long monolith. Multiple monolithic columns produced to the same recipes gave RSD data for retention factors of ions). The monolithic chelating ion-exchanger was applied to the separation of alkaline earth and transition metal ions spiked in natural and potable waters.
Jiang, Xiaoya; Zhang, Doudou; Li, Xueying; Wang, Xixi; Bai, Ligai; Liu, Haiyan; Yan, Hongyuan
2017-05-10
A novel polymer-based monolithic column was prepared via redox initiation system within the confines of a stainless steel column with 4.6mm i.d. In the processes, hemin and lauryl methacrylate were used as co-monomers; ethylene dimethacrylate as crosslinking agent; n-butyl alcohol, ethanediol, and N, N-dimethylformamide as tri-porogens; benzoyl peroxide and N, N-dimethyl aniline as redox initiation system. The resulting polymer-based monolithic columns were characterized by scanning electron microscopy, nitrogen adsorption-desorption instrument, and mercury intrusion porosimeter, respectively. The results illustrated that the improved monolith had relative uniform porous structure, good permeability, and low back pressure. Aromatic compounds were used to test the chromatographic behavior of the monolith, resulting in highest column efficiency of 19 880 plates per meter with reversed-phase mechanism. Furthermore, the homemade monolith was used as the stationary phase of high performance liquid chromatography to separate proteins from complex bio-matrix, including human plasma, egg white, and snailase. The results showed that the monolithic column occupied good separation ability with these complex bio-samples. Excellent specific character of the homemade hemin-based monolith was that it could simultaneously remove high-abundance proteins (including human serum albumin, immunoglobulin G, and human fibrinogen) from human plasma and separate other proteins to different fractions. Copyright © 2017 Elsevier B.V. All rights reserved.
Buffer-regulated biocorrosion of pure magnesium.
Kirkland, Nicholas T; Waterman, Jay; Birbilis, Nick; Dias, George; Woodfield, Tim B F; Hartshorn, Richard M; Staiger, Mark P
2012-02-01
Magnesium (Mg) alloys are being actively investigated as potential load-bearing orthopaedic implant materials due to their biodegradability in vivo. With Mg biomaterials at an early stage in their development, the screening of alloy compositions for their biodegradation rate, and hence biocompatibility, is reliant on cost-effective in vitro methods. The use of a buffer to control pH during in vitro biodegradation is recognised as critically important as this seeks to mimic pH control as it occurs naturally in vivo. The two different types of in vitro buffer system available are based on either (i) zwitterionic organic compounds or (ii) carbonate buffers within a partial-CO(2) atmosphere. This study investigated the influence of the buffering system itself on the in vitro corrosion of Mg. It was found that the less realistic zwitterion-based buffer did not form the same corrosion layers as the carbonate buffer, and was potentially affecting the behaviour of the hydrated oxide layer that forms on Mg in all aqueous environments. Consequently it was recommended that Mg in vitro experiments use the more biorealistic carbonate buffering system when possible.
Monolithic integration of microfluidic channels and semiconductor lasers
Cran-McGreehin, Simon J.; Dholakia, Kishan; Krauss, Thomas F.
2006-08-01
We present a fabrication method for the monolithic integration of microfluidic channels into semiconductor laser material. Lasers are designed to couple directly into the microfluidic channel, allowing submerged particles pass through the output beams of the lasers. The interaction between particles in the channel and the lasers, operated in either forward or reverse bias, allows for particle detection, and the optical forces can be used to trap and move particles. Both interrogation and manipulation are made more amenable for lab-on-a-chip applications through monolithic integration. The devices are very small, they require no external optical components, have perfect intrinsic alignment, and can be created with virtually any planar configuration of lasers in order to perform a variety of tasks. Their operation requires no optical expertise and only low electrical power, thus making them suitable for computer interfacing and automation. Insulating the pn junctions from the fluid is the key challenge, which is overcome by using photo-definable SU8-2000 polymer.
Development of stable monolithic wide-field Michelson interferometers.
Wan, Xiaoke; Ge, Jian; Chen, Zhiping
2011-07-20
Bulk wide-field Michelson interferometers are very useful for high precision applications in remote sensing and astronomy. A stable monolithic Michelson interferometer is a key element in high precision radial velocity (RV) measurements for extrasolar planets searching and studies. Thermal stress analysis shows that matching coefficients of thermal expansion (CTEs) is a critical requirement for ensuring interferometer stability. This requirement leads to a novel design using BK7 and LAK7 materials, such that the monolithic interferometer is free from thermal distortion. The processes of design, fabrication, and testing of interferometers are described in detail. In performance evaluations, the field angle is typically 23.8° and thermal sensitivity is typically -2.6×10(-6)/°C near 550 nm, which corresponds to ∼800 m/s/°C in the RV scale. Low-cost interferometer products have been commissioned in multiple RV instruments, and they are producing high stability performance over long term operations. © 2011 Optical Society of America
European Research on THz Vacuum Amplifiers
DEFF Research Database (Denmark)
Brunetti, F.; Cojocarua, C.-S.; de Rossi, A.
2010-01-01
The OPTHER (OPtically Driven TeraHertz AmplifiERs) project represents a considerable advancement in the field of high frequency amplification. The design and realization of a THz amplifier within this project is a consolidation of efforts at the international level from the main players...... of the European research, academy and industry in vacuum electronics. This paper describes the status of the project and progress towards the THz amplifier realization....
Integrated amplifying circuit with MOS transistors
Energy Technology Data Exchange (ETDEWEB)
Baylac, B; Merckel, G; Meunier, P
1974-01-25
The invention relates to a feedback-pass-band amplifier with MOS-transistors. The differential stage of conventional amplifiers is changed into an adding state, whereas the differential amplification stages are changed into amplifier inverter stages. All MOS transistors used in that amplifier are of similar configuration and are interdigitized, whereby the operating speed dispersion is reduced. This can be applied to obtaining a measurement channel for proportional chambers.
Microstructural characteristics of HIP-bonded monolithic nuclear fuels with a diffusion barrier
Jue, Jan-Fong; Keiser, Dennis D.; Breckenridge, Cynthia R.; Moore, Glenn A.; Meyer, Mitchell K.
2014-05-01
Due to the limitation of maximum uranium load achievable by dispersion fuel type, the Global Threat Reduction Initiative is developing an advanced monolithic fuel to convert US high-performance research reactors to low-enriched uranium. Hot-isostatic-press (HIP) bonding was the single process down-selected to bond monolithic U-Mo fuel meat to aluminum alloy cladding. A diffusion barrier was applied to the U-Mo fuel meat by roll-bonding process to prevent extensive interaction between fuel meat and aluminum-alloy cladding. Microstructural characterization was performed on fresh fuel plates fabricated at Idaho National Laboratory. Interfaces between the fuel meat, the cladding, and the diffusion barrier, as well as between the U-10Mo fuel meat and the Al-6061 cladding, were characterized by scanning electron microscopy. Preliminary results indicate that the interfaces contain many different phases while decomposition, second phases, and chemical banding were also observed in the fuel meat. The important attributes of the HIP-bonded monolithic fuel are: line. Some of these attributes might be critical to the irradiation performance of monolithic U-10Mo nuclear fuel. There are several issues or concerns that warrant more detailed study, such as precipitation along the cladding-to-cladding bond line, chemical banding, uncovered fuel-zone edge, and the interaction layer between the U-Mo fuel meat and zirconium. Future post-irradiation examination results will focus, among other things, on identifying in-reactor failure mechanisms and, eventually, directing further fresh fuel characterization efforts.
Imaging monolithic silicon detector telescopes
International Nuclear Information System (INIS)
Amorini, F.; Sipala, V.; Cardella, G.; Boiano, C.; Carbone, B.; Cosentino, L.; Costa, E.; Di Pietro, A.; Emanuele, U.; Fallica, G.; Figuera, P.; Finocchiaro, P.; La Guidara, E.; Marchetta, C.; Pappalardo, A.; Piazza, A.; Randazzo, N.; Rizzo, F.; Russo, G.V.; Russotto, P.
2008-01-01
We show the results of some test beams performed on a new monolithic strip silicon detector telescope developed in collaboration with the INFN and ST-microelectronics. Using an appropriate design, the induction on the ΔE stages, generated by the charge released in the E stage, was used to obtain the position of the detected particle. The position measurement, together with the low threshold for particle charge identification, allows the new detector to be used for a large variety of applications due to its sensitivity of only a few microns measured in both directions
Urban, Jiří T.
2011-09-26
An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. © 2011 Wiley Periodicals, Inc.
Urban, Jiří T.; Švec, František; Frechet, Jean
2011-01-01
An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. © 2011 Wiley Periodicals, Inc.
Urban, Jiri; Svec, Frantisek; Fréchet, Jean M J
2012-02-01
An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37°C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel. Copyright © 2011 Wiley Periodicals, Inc.
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.
Sahli, Florent
2017-10-09
Perovskite/silicon tandem solar cells are increasingly recognized as promising candidates for next-generation photovoltaics with performance beyond the single-junction limit at potentially low production costs. Current designs for monolithic tandems rely on transparent conductive oxides as an intermediate recombination layer, which lead to optical losses and reduced shunt resistance. An improved recombination junction based on nanocrystalline silicon layers to mitigate these losses is demonstrated. When employed in monolithic perovskite/silicon heterojunction tandem cells with a planar front side, this junction is found to increase the bottom cell photocurrent by more than 1 mA cm−2. In combination with a cesium-based perovskite top cell, this leads to tandem cell power-conversion efficiencies of up to 22.7% obtained from J–V measurements and steady-state efficiencies of up to 22.0% during maximum power point tracking. Thanks to its low lateral conductivity, the nanocrystalline silicon recombination junction enables upscaling of monolithic perovskite/silicon heterojunction tandem cells, resulting in a 12.96 cm2 monolithic tandem cell with a steady-state efficiency of 18%.
Directory of Open Access Journals (Sweden)
Natalita Maulani Nursam
2017-12-01
Full Text Available Dye-sensitized solar cells (DSSC are widely developed due to their attractive appearance and simple fabrication processes. One of the challenges that arise in the DSSC fabrication involves high material cost associated with the cost of conductive substrate. DSSC with monolithic configuration was then developed on the basis of this motivation. In this contribution, titanium dioxide-based monolithic type DSSCs were fabricated on a single fluorine-doped transparent oxide coated glass using porous ZrO2 as spacer. Herein, the catalytic material for the counter-electrode was varied using carbon composite and platinum in order to analyze their effect on the solar cell efficiency. Four-point probe measurement revealed that the carbon composite exhibited slightly higher conductivity with a sheet resistance of 9.8 Ω/sq and 10.9 Ω/sq for carbon and platinum, respectively. Likewise, the photoconversion efficiency of the monolithic cells with carbon counter-electrode almost doubled the efficiency of the cells with platinum counter-electrode. Our results demonstrate that carbon could outperform the performance of platinum as catalytic material in monolithic DSSC.
Sahli, Florent; Kamino, Brett A.; Werner, Jé ré mie; Brä uninger, Matthias; Paviet-Salomon, Bertrand; Barraud, Loris; Monnard, Raphaë l; Seif, Johannes Peter; Tomasi, Andrea; Jeangros, Quentin; Hessler-Wyser, Aï cha; De Wolf, Stefaan; Despeisse, Matthieu; Nicolay, Sylvain; Niesen, Bjoern; Ballif, Christophe
2017-01-01
Perovskite/silicon tandem solar cells are increasingly recognized as promising candidates for next-generation photovoltaics with performance beyond the single-junction limit at potentially low production costs. Current designs for monolithic tandems rely on transparent conductive oxides as an intermediate recombination layer, which lead to optical losses and reduced shunt resistance. An improved recombination junction based on nanocrystalline silicon layers to mitigate these losses is demonstrated. When employed in monolithic perovskite/silicon heterojunction tandem cells with a planar front side, this junction is found to increase the bottom cell photocurrent by more than 1 mA cm−2. In combination with a cesium-based perovskite top cell, this leads to tandem cell power-conversion efficiencies of up to 22.7% obtained from J–V measurements and steady-state efficiencies of up to 22.0% during maximum power point tracking. Thanks to its low lateral conductivity, the nanocrystalline silicon recombination junction enables upscaling of monolithic perovskite/silicon heterojunction tandem cells, resulting in a 12.96 cm2 monolithic tandem cell with a steady-state efficiency of 18%.
Buffer protection in the installation phase
International Nuclear Information System (INIS)
Wimelius, Hans; Pusch, Roland
2008-12-01
The research and development of the design and construction of the SKB's repository for final disposal of spent reactor fuel is conducted along several paths ('lines'). Issues concerning the bedrock are dealt with in the 'rock line' and those related to buffer and backfill in deposition holes and tunnels are considered in the 'buffer line' and 'backfill line', respectively. These lines also deal with sub-activities that are coupled to several other lines. One of them includes development of techniques for protecting buffer blocks from moisture and water in the installation phase. Techniques and methods for placement and removal of the 'buffer protection sheet' are dealt with in the 'buffer line'. The removal is, however, considered as being part of the backfilling sequence. Since the performance of the sheet is of fundamental importance to the placement and function of the buffer it deserves particular attention. Thus, the removal of the rubber sheet that serves to protect the buffer blocks in the installation phase may be difficult and can cause significant problems that may require retrieval of already placed canister, buffer and backfill. These matters are in focus in the present report. Arrangements for protecting already placed buffer blocks from moist air and water have been tested in earlier large-scale experiments, i.e. the Prototype Repository project at Aespoe but the experience from them has called for more effective protection of the clay blocks as described in the present report. Focus is on the construction of foundation components at the bottom of the deposition holes required for establishing a tight seal between rock and buffer blocks, and on the protection sheet and arrangements for limiting water pressure on it. Special attention is paid to the drainage of the space between rock and protection sheet that is necessary for avoiding failure of the sheet and to systems for achieving this and for providing alarm signals if the allowed pressure is
Mathematical Modelling of Optimization of Structures of Monolithic Coverings Based on Liquid Rubbers
Turgumbayeva, R. Kh; Abdikarimov, M. N.; Mussabekov, R.; Sartayev, D. T.
2018-05-01
The paper considers optimization of monolithic coatings compositions using a computer and MPE methods. The goal of the paper was to construct a mathematical model of the complete factorial experiment taking into account its plan and conditions. Several regression equations were received. Dependence between content components and parameters of rubber, as well as the quantity of a rubber crumb, was considered. An optimal composition for manufacturing the material of monolithic coatings compositions was recommended based on experimental data.
Novel design of low-jitter 10 GHz all-active monolithic mode-locked lasers
DEFF Research Database (Denmark)
Larsson, David; Yvind, Kresten; Christiansen, Lotte Jin
2004-01-01
Using a novel design, we have fabricated 10 GHz all-active monolithic mode-locked semiconductor lasers that generate 1.4 ps pulses with record-low timing jitter. The dynamical properties of lasers with 1 and 2 QWs are compared.......Using a novel design, we have fabricated 10 GHz all-active monolithic mode-locked semiconductor lasers that generate 1.4 ps pulses with record-low timing jitter. The dynamical properties of lasers with 1 and 2 QWs are compared....
Power Amplifiers in CMOS Technology: A contribution to power amplifier theory and techniques
Acar, M.
2011-01-01
In order to meet the demands from the market on cheaper, miniaturized mobile communications devices realization of RF power amplifiers in the mainstream CMOS technology is essential. In general, CMOS Power Amplifiers (PAs) require high voltage to decrease the matching network losses and for high
International Nuclear Information System (INIS)
Belforte, S.; Dell'Orso, M.; Donati, S.
1996-01-01
The Hit Buffer is part of the Silicon Vertex Tracker, a trigger processor dedicated to the reconstruction of particle trajectories in the Silicon Vertex Detector and the Central Tracking Chamber of the Collider Detector at Fermilab. The Hit Buffer is a high speed data-traffic node, where thousands of words are received in arbitrary order and simultaneously organized in an internal structured data base, to be later promptly retrieved and delivered in response to specific requests. The Hit Buffer is capable of processing data at a rate of 25 MHz, thanks to the use of special fast devices like Cache-Tag RAMs and high performance Erasable Programmable Logic Devices from the XILINX XC7300 family
Regional waste treatment with monolith disposal for low-level radioactive waste
International Nuclear Information System (INIS)
Forsberg, C.W.
1983-01-01
An alternative system is proposed for the disposal of low-level radioactive waste. This system, called REgional Treatment with MOnolith Disposal (RETMOD), is based on integrating three commercial technologies: automated package warehousing, whole-barrel rotary kiln incineration, and cement-based grouts for radioactive waste disposal. In the simplified flowsheet, all the sludges, liquids, resins, and combustible wastes are transported to regional facilities where they are incinerated. The ash is then mixed with special cement-based grouts, and the resulting mixture is poured into trenches to form large waste-cement monoliths. Wastes that do not require treatment, such as damaged and discarded equipment, are prepositioned in the trenches with the waste-cement mixture poured on top. The RETMOD system may provide higher safety margins by conversion of wastes into a solidified low-leach form, creation of low-surface area waste-cement monoliths, and centralization of waste processing into a few specialized facilities. Institutional problems would be simplified by placing total responsibility for safe disposal on the disposal site operator. Lower costs may be realized through reduced handling costs, the economics of scale, simplified operations, and less restrictive waste packaging requirements
Optical Regeneration and Noise in Semiconductor Devices
DEFF Research Database (Denmark)
Öhman, Filip
2005-01-01
In this report all-optical 2R-regeneration in optical communication systems is investigated. A simple regenerator device based on concatenated semiconductor optical amplifiers (SOAs) and electro absorbers (EAs) is introduced and examined. Experiments show that the monolithic SOA-EA 2R-regenerator......In this report all-optical 2R-regeneration in optical communication systems is investigated. A simple regenerator device based on concatenated semiconductor optical amplifiers (SOAs) and electro absorbers (EAs) is introduced and examined. Experiments show that the monolithic SOA-EA 2R...
Enhanced performance CCD output amplifier
Dunham, Mark E.; Morley, David W.
1996-01-01
A low-noise FET amplifier is connected to amplify output charge from a che coupled device (CCD). The FET has its gate connected to the CCD in common source configuration for receiving the output charge signal from the CCD and output an intermediate signal at a drain of the FET. An intermediate amplifier is connected to the drain of the FET for receiving the intermediate signal and outputting a low-noise signal functionally related to the output charge signal from the CCD. The amplifier is preferably connected as a virtual ground to the FET drain. The inherent shunt capacitance of the FET is selected to be at least equal to the sum of the remaining capacitances.
Zhou, Chanyuan; Chen, Xiaoman; Du, Zhuo; Li, Gongke; Xiao, Xiaohua; Cai, Zongwei
2017-05-19
A hybrid monolithic column based on aminophenylboronic acid (APBA)-functionalized graphene oxide (GO) has been developed and used for selective enrichment of glycoproteins. The APBA/GO composites were homogeneously incorporated into a polymer monolithic column with the help of oligomer matrix and followed by in situ polymerization. The effect of dispersion of APBA/GO composites in the polymerization mixture on the performance of the monolithic column was explored in detail. The presence of graphene oxide not only enlarged the BET surface area from 6.3m 2 /g to 169.4m 2 /g, but also provided abundant boronic acid moieties for glycoprotein extraction, which improved the enrichment selectivity and efficiency for glycoproteins. The APBA/GO hybrid monolithic column was incorporated into a sequential injection system, which facilitated online extraction of proteins. Combining the superior properties of extraordinary surface area of GO and the affinity interaction of APBA to glycoproteins, the APBA/GO hybrid monolithic column showed higher enrichment factors for glycoproteins than other proteins without cis-diol-containing groups. Also, under comparable or even shorter processing time and without the addition of any organic solvent, it showed higher binding capacity toward glycoproteins compared with the conventional boronate affinity monolithic column. The practical applicability of this system was demonstrated by processing of egg white samples for extraction of ovalbumin and ovotransferrin, and satisfactory results were obtained by assay with SDS-PAGE. Copyright © 2017 Elsevier B.V. All rights reserved.
Zeng, Jiao; Liu, Shengquan; Wang, Menglin; Yao, Shouzhuo; Chen, Yingzhuang
2017-05-01
In this work, a porous structure and good permeability monolithic column was polymerized in UV transparent fused-silica capillaries via photo-initiated thiol-ene click polymerization of 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane (TMTVS), pentaerythritol tetra(3-mercaptopropionate)(PETMP), itaconic acid, respectively, in the presence of porogenic solvents (tetrahydrofuranand methanol) and an initiator (2,2-dimethoxy-2-phenylacetophenone) (DMPA) within 30 min. The physical properties of this monolith were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and nitrogen adsorption/desorption measurements. For an overall evaluation of the monolith in chromatographic application, separations of polycyclic aromatic hydrocarbons (PAHs), phenols, amides and bases were carried out. The column efficiency of this monolith could be as high as 112 560 N/m. It also possesses a potential application in fabrication of monoliths with high efficiency for c-LC. In addition, the resulting monolithic column demonstrated the potential use in analysis of environment waters. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Transmission characteristics of acoustic amplifier in thermoacoustic engine
International Nuclear Information System (INIS)
Sun Daming; Qiu Limin; Wang Bo; Xiao Yong
2008-01-01
Thermoacoustic engines are promising in practical applications for the merits of simple configuration, reliable operation and environmentally friendly working gas. An acoustic amplifier can increase the output pressure amplitude of a thermoacoustic engine (TE) and improve the matching between the engine and its load. In order to make full use of an acoustic amplifier, the transmission characteristics are studied based on linear thermoacoustic theory. Computational and experimental results show that the amplifying ability of an acoustic amplifier is mainly determined by its geometry parameters and output resistance impedance. The amplifying ability of an acoustic amplifier with appropriate length and diameter reaches its maximum when the output resistance impedance is infinite. It is also shown that the acoustic amplifier consumes an amount of acoustic power when amplifying pressure amplitude and the acoustic power consumption increases with amplifying ratio. Furthermore, a novel cascade acoustic amplifier is proposed, which has a much stronger amplifying ability with reduced acoustic power consumption. In experiments, a two-stage cascade acoustic amplifier amplifies the pressure ratio from 1.177 to 1.62 and produces a pressure amplitude of 0.547 MPa with nitrogen of 2.20 MPa as working gas. Good agreements are obtained between the theoretical analysis and experimental results. This research is instructive for comprehensively understanding the mechanism and making full use of the acoustic amplifier
Electrodialysis operation with buffer solution
Hryn, John N [Naperville, IL; Daniels, Edward J [Orland Park, IL; Krumdick, Greg K [Crete, IL
2009-12-15
A new method for improving the efficiency of electrodialysis (ED) cells and stacks, in particular those used in chemical synthesis. The process entails adding a buffer solution to the stack for subsequent depletion in the stack during electrolysis. The buffer solution is regenerated continuously after depletion. This buffer process serves to control the hydrogen ion or hydroxide ion concentration so as to protect the active sites of electrodialysis membranes. The process enables electrodialysis processing options for products that are sensitive to pH changes.
Tanemura, T.; Soganci, I. M.; Oyama, T.; Ohyama, T.; Mino, S.; Williams, K. A.; Calabretta, N.; Dorren, H. J S; Nakano, Y.
2010-01-01
We demonstrate large-capacity high-resolution optical buffer, comprising 1×16 InP switch and ultra-compact delay lines based on thin-cladding highly nonlinear fibers. Silica-PLC-based pitch converter is employed to realize uniform coupling from all 16 switch ports simultaneously.
Buffered Communication Analysis in Distributed Multiparty Sessions
Deniélou, Pierre-Malo; Yoshida, Nobuko
Many communication-centred systems today rely on asynchronous messaging among distributed peers to make efficient use of parallel execution and resource access. With such asynchrony, the communication buffers can happen to grow inconsiderately over time. This paper proposes a static verification methodology based on multiparty session types which can efficiently compute the upper bounds on buffer sizes. Our analysis relies on a uniform causality audit of the entire collaboration pattern - an examination that is not always possible from each end-point type. We extend this method to design algorithms that allocate communication channels in order to optimise the memory requirements of session executions. From these analyses, we propose two refinements methods which respect buffer bounds: a global protocol refinement that automatically inserts confirmation messages to guarantee stipulated buffer sizes and a local protocol refinement to optimise asynchronous messaging without buffer overflow. Finally our work is applied to overcome a buffer overflow problem of the multi-buffering algorithm.
Catalytic Oxidation of Cyanogen Chloride over a Monolithic Oxidation Catalyst
National Research Council Canada - National Science Library
Campbell, Jeffrey
1997-01-01
The catalytic oxidation of cyanogen chloride was evaluated over a monolithic oxidation catalyst at temperatures between 200 and 300 deg C in air employing feed concentrations between 100 and 10,000 ppm...
Buffer protection in the installation phase
Energy Technology Data Exchange (ETDEWEB)
Wimelius, Hans (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Pusch, Roland (Geodevelopment International AB, Lund (Sweden))
2008-12-15
The research and development of the design and construction of the SKB's repository for final disposal of spent reactor fuel is conducted along several paths ('lines'). Issues concerning the bedrock are dealt with in the 'rock line' and those related to buffer and backfill in deposition holes and tunnels are considered in the 'buffer line' and 'backfill line', respectively. These lines also deal with sub-activities that are coupled to several other lines. One of them includes development of techniques for protecting buffer blocks from moisture and water in the installation phase. Techniques and methods for placement and removal of the 'buffer protection sheet' are dealt with in the 'buffer line'. The removal is, however, considered as being part of the backfilling sequence. Since the performance of the sheet is of fundamental importance to the placement and function of the buffer it deserves particular attention. Thus, the removal of the rubber sheet that serves to protect the buffer blocks in the installation phase may be difficult and can cause significant problems that may require retrieval of already placed canister, buffer and backfill. These matters are in focus in the present report. Arrangements for protecting already placed buffer blocks from moist air and water have been tested in earlier large-scale experiments, i.e. the Prototype Repository project at Aespoe but the experience from them has called for more effective protection of the clay blocks as described in the present report. Focus is on the construction of foundation components at the bottom of the deposition holes required for establishing a tight seal between rock and buffer blocks, and on the protection sheet and arrangements for limiting water pressure on it. Special attention is paid to the drainage of the space between rock and protection sheet that is necessary for avoiding failure of the sheet and to systems for achieving
Liu, Jianfei; Chen, Xiangli; Wang, Pei; Fu, Xuwei; Liu, Kaiqiang; Fang, Yu
2017-08-01
Porous polymeric monoliths with densities as low as ≈0.060 g cm -3 are prepared in a gel-emulsion template way, of which the stabilizer employed is a newly discovered acidified aramid fiber that is so efficient that 0.05% (w/v, accounts for continuous phase) is enough to gel the system. The porous monoliths as obtained can be dried at ambient conditions, avoiding energy-consuming processes. Importantly, the monoliths show selective adsorption to HCHO, and the corresponding adsorption capacity (M6) is ≈2700 mg g -1 , the best result that is reported until now. More importantly, the monoliths can be reused after drying. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Baicu, Simona C; Taylor, Michael J
2002-08-01
Control of acidity and preventing intracellular acidosis are recognized as critical properties of an effective organ preservation solution. Buffer capacity and efficiency are therefore important for comparing the relative merits of preservation fluids for optimum hypothermic storage, but these parameters are not available for the variety of organ preservation solutions of interest in transplantation today. Moreover, buffer capacity is dependent upon both concentration and pH such that buffer capacity is not easily predicted for a complex solution containing multiple buffer species. Using standard electrometric methods to measure acid dissociation constants, this study was undertaken to determine the maximum and relative buffer capacities of a variety of new and commonly used hypothermic preservation solutions as a function of temperature. The reference data provided by these measurements show that comparative buffer capacity and efficiency vary widely between the commonly used solutions. Moreover, the fluids containing zwitterionic sulfonic acid buffers such as Hepes possess superior buffering for alpha-stat pH regulation in the region of physiological importance.
Mitov, Gergo; Anastassova-Yoshida, Yana; Nothdurft, Frank Phillip; von See, Constantin; Pospiech, Peter
2016-02-01
The aim of this study was to evaluate the fracture resistance and fracture behavior of monolithic zirconia crowns in accordance with the preparation design and aging simulation method. An upper first molar was prepared sequentially with three different preparation designs: shoulderless preparation, 0.4 mm chamfer and 0.8 mm chamfer preparation. For each preparation design, 30 monolithic zirconia crowns were fabricated. After cementation on Cr-Co alloy dies, the following artificial aging procedures were performed: (1) thermal cycling and mechanical loading (TCML): 5000 cycles of thermal cycling 5℃-55℃ and chewing simulation (1,200,000 cycles, 50 N); (2) Low Temperature Degradation simulation (LTD): autoclave treatment at 137℃, 2 bar for 3 hours and chewing simulation; and (3) no pre-treatment (control group). After artificial aging, the crowns were loaded until fracture. The mean values of fracture resistance varied between 3414 N (LTD; 0.8 mm chamfer preparation) and 5712 N (control group; shoulderless preparation). Two-way ANOVA analysis showed a significantly higher fracture loads for the shoulderless preparation, whereas no difference was found between the chamfer preparations. In contrast to TCML, after LTD simulation the fracture strength of monolithic zirconia crowns decreased significantly. The monolithic crowns tested in this study showed generally high fracture load values. Preparation design and LTD simulation had a significant influence on the fracture strength of monolithic zirconia crowns.
Towards Optimal Buffer Size in Wi-Fi Networks
Showail, Ahmad J.
2016-01-19
Buffer sizing is an important network configuration parameter that impacts the quality of data traffic. Falling memory cost and the fallacy that ‘more is better’ lead to over provisioning network devices with large buffers. Over-buffering or the so called ‘bufferbloat’ phenomenon creates excessive end-to-end delay in today’s networks. On the other hand, under-buffering results in frequent packet loss and subsequent under-utilization of network resources. The buffer sizing problem has been studied extensively for wired networks. However, there is little work addressing the unique challenges of wireless environment. In this dissertation, we discuss buffer sizing challenges in wireless networks, classify the state-of-the-art solutions, and propose two novel buffer sizing schemes. The first scheme targets buffer sizing in wireless multi-hop networks where the radio spectral resource is shared among a set of con- tending nodes. Hence, it sizes the buffer collectively and distributes it over a set of interfering devices. The second buffer sizing scheme is designed to cope up with recent Wi-Fi enhancements. It adapts the buffer size based on measured link characteristics and network load. Also, it enforces limits on the buffer size to maximize frame aggregation benefits. Both mechanisms are evaluated using simulation as well as testbed implementation over half-duplex and full-duplex wireless networks. Experimental evaluation shows that our proposal reduces latency by an order of magnitude.
Yang, Shengchao; Ye, Fanggui; Lv, Qinghui; Zhang, Cong; Shen, Shufen; Zhao, Shulin
2014-09-19
Metal-organic framework (MOF) HKUST-1 nanoparticles have been incorporated into poly(glycidyl methacrylate-co-ethylene dimethacrylate) (HKUST-1-poly(GMA-co-EDMA)) monoliths to afford stationary phases with enhanced chromatographic performance of small molecules in the reversed phase capillary liquid chromatography. The effect of HKUST-1 nanoparticles in the polymerization mixture on the performance of the monolithic column was explored in detail. While the bare poly(GMA-co-EDMA) monolith exhibited poor resolution (RsHKUST-1 nanoparticles to the polymerization mixture provide high increased resolution (Rs≥1.3) and high efficiency ranged from 16,300 to 44,300plates/m. Chromatographic performance of HKUST-1-poly(GMA-co-EDMA) monolith was demonstrated by separation of various analytes including polycyclic aromatic hydrocarbons, ethylbenzene and styrene, phenols and aromatic acids using a binary polar mobile phase (CH3CN/H2O). The HKUST-1-poly(GMA-co-EDMA) monolith displayed enhanced hydrophobic and π-π interaction characteristics in the reversed phase separation of test analytes compared to the bare poly(GMA-co-EDMA) monolith. The experiment results showed that HKUST-1-poly(GMA-co-EDMA) monoliths are an alternative to enhance the chromatographic separation of small molecules. Copyright © 2014 Elsevier B.V. All rights reserved.
Riesová, Martina; Svobodová, Jana; Tošner, Zdeněk; Beneš, Martin; Tesařová, Eva; Gaš, Bohuslav
2013-09-17
The complexation of buffer constituents with the complexation agent present in the solution can very significantly influence the buffer properties, such as pH, ionic strength, or conductivity. These parameters are often crucial for selection of the separation conditions in capillary electrophoresis or high-pressure liquid chromatography (HPLC) and can significantly affect results of separation, particularly for capillary electrophoresis as shown in Part II of this paper series (Beneš, M.; Riesová, M.; Svobodová, J.; Tesařová, E.; Dubský, P.; Gaš, B. Anal. Chem. 2013, DOI: 10.1021/ac401381d). In this paper, the impact of complexation of buffer constituents with a neutral complexation agent is demonstrated theoretically as well as experimentally for the model buffer system composed of benzoic acid/LiOH or common buffers (e.g., CHES/LiOH, TAPS/LiOH, Tricine/LiOH, MOPS/LiOH, MES/LiOH, and acetic acid/LiOH). Cyclodextrins as common chiral selectors were used as model complexation agents. We were not only able to demonstrate substantial changes of pH but also to predict the general complexation characteristics of selected compounds. Because of the zwitterion character of the common buffer constituents, their charged forms complex stronger with cyclodextrins than the neutral ones do. This was fully proven by NMR measurements. Additionally complexation constants of both forms of selected compounds were determined by NMR and affinity capillary electrophoresis with a very good agreement of obtained values. These data were advantageously used for the theoretical descriptions of variations in pH, depending on the composition and concentration of the buffer. Theoretical predictions were shown to be a useful tool for deriving some general rules and laws for complexing systems.
Monolithic stabilized Yb-fiber All-PM laser directly delivering nJ-level femtosecond pulses
DEFF Research Database (Denmark)
Turchinovich, Dmitry; Liu, Xiaomin; Lægsgaard, Jesper
2008-01-01
We present a monolithic, self-starting, all-PM, stabilized Yb-fiber laser, pulse-compressed in a hollow-core PM photonic crystal fiber, providing the 370 fs pulses of 4 nJ energy with high mode quality.......We present a monolithic, self-starting, all-PM, stabilized Yb-fiber laser, pulse-compressed in a hollow-core PM photonic crystal fiber, providing the 370 fs pulses of 4 nJ energy with high mode quality....
Šesták, Jozef; Thormann, Wolfgang
2017-08-25
Part I on head-column field-amplified sample stacking comprised a detailed study of the electrokinetic injection of a weak base across a short water plug into a phosphate buffer at low pH. The water plug is converted into a low conductive acidic zone and cationic analytes become stacked at the interface between this and a newly formed phosphoric acid zone. The fundamentals of electrokinetic processes occurring thereafter were studied experimentally and with computer simulation and are presented as part II. The configuration analyzed represents a discontinuous buffer system. Computer simulation revealed that the phosphoric acid zone at the plug-buffer interface becomes converted into a migrating phosphate buffer plug which corresponds to the cationically migrating system zone of the phosphate buffer system. Its mobility is higher than that of the analytes such that they migrate behind the system zone in a phosphate buffer comparable to the applied background electrolyte. The temporal behaviour of the current and the conductivity across the water plug were monitored and found to reflect the changes in the low conductivity plug. Determination of the buffer flow in the capillary revealed increased pumping caused by the mismatch of electroosmosis within the low conductivity plug and the buffer. This effect becomes elevated with increasing water plug length. For plug lengths up to 1% of the total column length the flow quickly drops to the electroosmotic flow of the buffer and simulations with experimentally determined current and flow values predict negligible band dispersion and no loss of resolution for both low and large molecular mass components. Copyright © 2017 Elsevier B.V. All rights reserved.
Final amplifier design and mercury
International Nuclear Information System (INIS)
Rose, E.A.; Hanson, D.E.
1991-01-01
The final amplifier for the Mercury KrF excimer facility is being designed. The design exercise involves extensive modeling to predict amplifier performance. Models of the pulsed-power system, including a Child-Langmuir diode with closure, electron-beam energy deposition, KrF laser kinetics, amplified spontaneous emission (ASE), a time-dependent laser extraction in the presence of ASE are presented as a design package. The design exercise indicates that the energy objective of Phase I -- 100 joules -- will be met
A monolithic silicon detector telescope
International Nuclear Information System (INIS)
Cardella, G.; Amorini, F.; Cabibbo, M.; Di Pietro, A.; Fallica, G.; Franzo, G.; Figuera, P.; Papa, M.; Pappalardo, G.; Percolla, G.; Priolo, F.; Privitera, V.; Rizzo, F.; Tudisco, S.
1996-01-01
An ultrathin silicon detector (1 μm) thick implanted on a standard 400 μm Si-detector has been built to realize a monolithic telescope detector for simultaneous charge and energy determination of charged particles. The performances of the telescope have been tested using standard alpha sources and fragments emitted in nuclear reactions with different projectile-target colliding systems. An excellent charge resolution has been obtained for low energy (less than 5 MeV) light nuclei. A multi-array lay-out of such detectors is under construction to charge identify the particles emitted in reactions induced by low energy radioactive beams. (orig.)
A pulse amplifier for nuclear instrumentation
International Nuclear Information System (INIS)
Martin, D.; Cliff, P.
1987-01-01
A Class-A 1 Watt amplifier has been designed and optimized for nanosecond pulses. Spanning .01MHz to 1300Mhz, signal gain is 26dB with gain flatness of 1dB. The amplifier drive +- 10 volts across 500 with 350ps risetime. Each amplifier is housed in a 2-wide NIM
Nursam, Natalita M; Wang, Xingdong; Tan, Jeannie Z Y; Caruso, Rachel A
2016-07-13
Porous nitrogen-modified titania (N-titania) monoliths with tailored morphologies were prepared using phase separation and agarose gel templating techniques. The doping and templating process were simultaneously carried out in a one-pot step using alcohol amine-assisted sol-gel chemistry. The amount of polymer used in the monoliths that were prepared using phase separation was shown to affect both the physical and optical properties: higher poly(ethylene glycol) content increased the specific surface area, porosity, and visible light absorption of the final materials. For the agarose-templated monoliths, the infiltration conditions affected the monolith morphology. A porous monolith with high surface area and the least shrinkage was obtained when the N containing alkoxide precursor was infiltrated into the agarose scaffolds at 60 °C. The effect of the diverse porous morphologies on the photocatalytic activity of N-titania was studied for the decomposition of methylene blue (MB) under visible and UV light irradiation. The highest visible light activity was achieved by the agarose-templated N-titania monolith, in part due to higher N incorporation. This sample also showed better UV activity, partly because of the higher specific surface area (up to 112 m(2) g(-1)) compared to the phase separation-induced monoliths (up to 103 m(2) g(-1)). Overall, agarose-templated, porous N-titania monoliths provided better features for effectively removing the MB contaminant.
10Gbps monolithic silicon FTTH transceiver for PON
Zhang, J.; Liow, T. Y.; Lo, G. Q.; Kwong, D. L.
2010-05-01
We propose a new passive optical network (PON) configuration and a novel silicon photonic transceiver architecture for optical network unit (ONU), eliminating the need for an internal laser source in ONU. We adopt dual fiber network configuration. The internal light source in each of the ONUs is eliminated. Instead, an extra seed laser source in the optical line termination (OLT) operates in continuous wave mode to serve the ONUs in the PON as a shared and centralized laser source. λ1 from OLT Tx and λ2 from the seed laser are combined by using a WDM combiner and connected to serve the multiple ONUs through the downstream fibers. The ONUs receive the data in λ1. Meanwhile, the ONUs encode and transmit data in λ2, which are sent back to OLT. The monolithic ONU transceiver contains a wavelength-division-multiplexing (WDM) filter component, a silicon modulator and a Ge photo-detector. The WDM in ONU selectively guides λ1 to the Ge-PD where the data in λ1 are detected and converted to electrical signals, and λ2 to the transmitter where the light is modulated by upstream data. The modulated optical signals in λ2 from ONUs are connected back to OLT through upstream fibers. The monolithic ONU transceiver chip size is only 2mm by 4mm. The crosstalk between the Tx and Rx is measured to be less than -20dB. The transceiver chip is integrated on a SFP+ transceiver board. Both Tx and Rx demonstrated data rate capabilities of up to 10Gbps. By implementing this scheme, the ONU transceiver size can be significantly reduced and the assembly processes will be greatly simplified. The results demonstrate the feasibility of mass manufacturing monolithic silicon ONU transceivers via low cost
A TORC2-Akt feedforward topology underlies HER3 resiliency in HER2-amplified cancers
Amin, Dhara N.; Ahuja, Deepika; Yaswen, Paul; Moasser, Mark M.
2015-01-01
The requisite role of HER3 in HER2-amplified cancers is beyond what would be expected as a dimerization partner or effector substrate and it exhibits a substantial degree of resiliency that mitigates the effects of HER2-inhibitor therapies. To better understand the roots of this resiliency, we conducted an in-depth chemical-genetic interrogation of the signaling network downstream of HER3. A unique attribute of these tumors is the deregulation of TORC2. The upstream signals that ordinarily maintain TORC2 signaling are lost in these tumors, and instead TORC2 is driven by Akt. We find that in these cancers HER3 functions as a buffering arm of an Akt-TORC2 feed-forward loop that functions as a self-perpetuating module. This network topology alters the role of HER3 from a conditionally engaged ligand-driven upstream physiologic signaling input to an essential component of a concentric signaling throughput highly competent at preservation of homeostasis. The competence of this signaling topology is evident in its response to perturbation at any of its nodes. Thus a critical pathophysiological event in the evolution of HER2-amplified cancers is the loss of the input signals that normally drive TORC2 signaling, repositioning it under Akt dependency and fundamentally altering the role of HER3. This reprogramming of the downstream network topology is a key aspect in the pathogenesis of HER2-amplified cancers and constitutes a formidable barrier in the targeted therapy of these cancers. PMID:26438156
Role of the substrate in monolithic AlGaAs nonlinear nanoantennas
Directory of Open Access Journals (Sweden)
Gili Valerio Flavio
2017-06-01
Full Text Available We report the effect of the aluminum oxide substrate on the emission of monolithic AlGaAs-on-insulator nonlinear nanoantennas. By coupling nonlinear optical measurements with electron diffraction and microscopy observations, we find that the oxidation-induced stress causes negligible crystal deformation in the AlGaAs nanostructures and only plays a minor role in the polarization state of the harmonic field. This result highlights the reliability of the wet oxidation of thick AlGaAs optical substrates and further confirms the bulk χ(2 origin of second harmonic generation at 1.55 μm in these nanoantennas, paving the way for the development of AlGaAs-on-insulator monolithic metasurfaces.
A compact narrow-linewidth laser with a low-Q monolithic cavity
International Nuclear Information System (INIS)
Peng, Yu
2013-01-01
We demonstrate an approach to narrowing the linewidth of a diode laser to around 15×10 3 Hz with a compact setup of confocal and parallel monolithic Fabry–Perot cavities (MFCs). Resonances of the confocal and parallel MFCs with low finesse are obtained. Diode lasers with optical feedback from confocal and parallel monolithic MFCs are demonstrated. The frequency could be tuned 80×10 6 Hz by changing the grating position of the external cavity diode laser based on the confocal MFC, and 100×10 6 Hz by tuning the temperature of the plane MFC over 0.02 ° C for the external cavity diode laser based on the parallel MFC. (paper)
SODR Memory Control Buffer Control ASIC
Hodson, Robert F.
1994-01-01
The Spacecraft Optical Disk Recorder (SODR) is a state of the art mass storage system for future NASA missions requiring high transmission rates and a large capacity storage system. This report covers the design and development of an SODR memory buffer control applications specific integrated circuit (ASIC). The memory buffer control ASIC has two primary functions: (1) buffering data to prevent loss of data during disk access times, (2) converting data formats from a high performance parallel interface format to a small computer systems interface format. Ten 144 p in, 50 MHz CMOS ASIC's were designed, fabricated and tested to implement the memory buffer control function.
An Implantable CMOS Amplifier for Nerve Signals
DEFF Research Database (Denmark)
Nielsen, Jannik Hammel; Lehmann, Torsten
2003-01-01
In this paper, a low noise high gain CMOS amplifier for minute nerve signals is presented. The amplifier is constructed in a fully differential topology to maximize noise rejection. By using a mixture of weak- and strong inversion transistors, optimal noise suppression in the amplifier is achieved....... A continuous-time current-steering offset-compensation technique is utilized in order to minimize the noise contribution and to minimize dynamic impact on the amplifier input nodes. The method for signal recovery from noisy nerve signals is presented. A prototype amplifier is realized in a standard digital 0...
Monolithically integrated Helmholtz coils by 3-dimensional printing
Energy Technology Data Exchange (ETDEWEB)
Li, Longguang [Department of Electrical Engineering, University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Abedini-Nassab, Roozbeh; Yellen, Benjamin B., E-mail: yellen@duke.edu [Department of Electrical Engineering, University of Michigan–Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240 (China); Department of Mechanical Engineering and Materials Science, Duke University, P.O. Box 90300, Hudson Hall, Durham, North Carolina 27708 (United States)
2014-06-23
3D printing technology is of great interest for the monolithic fabrication of integrated systems; however, it is a challenge to introduce metallic components into 3D printed molds to enable broader device functionality. Here, we develop a technique for constructing a multi-axial Helmholtz coil by injecting a eutectic liquid metal Gallium Indium alloy (EGaIn) into helically shaped orthogonal cavities constructed in a 3D printed block. The tri-axial solenoids each carry up to 3.6 A of electrical current and produce magnetic field up to 70 G. Within the central section of the coil, the field variation is less than 1% and is in agreement with theory. The flow rates and critical pressures required to fill the 3D cavities with liquid metal also agree with theoretical predictions and provide scaling trends for filling the 3D printed parts. These monolithically integrated solenoids may find future applications in electronic cell culture platforms, atomic traps, and miniaturized chemical analysis systems based on nuclear magnetic resonance.
Monolithically integrated Helmholtz coils by 3-dimensional printing
International Nuclear Information System (INIS)
Li, Longguang; Abedini-Nassab, Roozbeh; Yellen, Benjamin B.
2014-01-01
3D printing technology is of great interest for the monolithic fabrication of integrated systems; however, it is a challenge to introduce metallic components into 3D printed molds to enable broader device functionality. Here, we develop a technique for constructing a multi-axial Helmholtz coil by injecting a eutectic liquid metal Gallium Indium alloy (EGaIn) into helically shaped orthogonal cavities constructed in a 3D printed block. The tri-axial solenoids each carry up to 3.6 A of electrical current and produce magnetic field up to 70 G. Within the central section of the coil, the field variation is less than 1% and is in agreement with theory. The flow rates and critical pressures required to fill the 3D cavities with liquid metal also agree with theoretical predictions and provide scaling trends for filling the 3D printed parts. These monolithically integrated solenoids may find future applications in electronic cell culture platforms, atomic traps, and miniaturized chemical analysis systems based on nuclear magnetic resonance.
International Nuclear Information System (INIS)
Tai, I.; Hasegawa, K.
1975-01-01
This paper reports on the improvement of frequency characteristics of a logarithmic amplifier with a Paterson transdiode connection. The improvement of the response speed has been achieved by using a phase compensation technique. Small signal response analyses of the logging circuit revealed the effects of a series resistor Rsub(p) and a parallel capacitance Csub(p) on the response of the circuit. The improvement of the frequency characteristics are remarkable at higher current levels. These facts were proved by the practical logarithmic amplifier. (auth.)
Monolithic Yb-fiber femtosecond laser using photonic crystal fiber
DEFF Research Database (Denmark)
Liu, Xiaomin; Lægsgaard, Jesper; Turchinovich, Dmitry
2008-01-01
We demonstrate, both experimentally and theoretically, an environmentally stable monolithic all-PM modelocked femtosecond Yb-fiber laser, with laser output pulse compressed in a spliced-on low-loss hollow-core photonic crystal fiber. Our laser provides direct fiber-end delivery of 4 nJ pulses...
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...
Flashlamp excited fluid laser amplified
International Nuclear Information System (INIS)
1976-01-01
The patent describes a laser amplifier with chambers for containing and amplifying an intensifier medium. It serves the need for a large impulse repetition rate and high intensities as required e.g. for laser isotope separation
Design considerations for RF power amplifiers demonstrated through a GSM/EDGE power amplifier module
Baltus, P.G.M.; Bezooijen, van A.; Huijsing, J.H.; Steyaert, M.; Roermund, van A.H.M.
2002-01-01
This paper describes the design considerations for RF power amplifiers in general, including trends in systems, linearity and efficiency, the PA environment, implementation is sues and technology. As an example a triple-band (900/1800/1900MHz) dual mode (GSMIEdge) power amplifier module is described
Dynamic mechanical properties of buffer material
International Nuclear Information System (INIS)
Takaji, Kazuhiko; Taniguchi, Wataru
1999-11-01
The buffer material is expected to maintain its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. over a long period of time. Natural clay is mentioned as a material that can relatively satisfy above. Among the kinds of natural clay, bentonite when compacted is superior because (i) it has exceptionally low water permeability and properties to control the movement of water in buffer, (ii) it fills void spaces in the buffer and fractures in the host rock as it swells upon water uptake, (iii) it has the ability to exchange cations and to adsorb cationic radioelements. In order to confirm these functions for the purpose of safety assessment, it is necessary to evaluate buffer properties through laboratory tests and engineering-scale tests, and to make assessments based on the ranges in the data obtained. This report describes the procedures, test conditions, results and examinations on the buffer material of dynamic triaxial tests, measurement of elastic wave velocity and liquefaction tests that aim at getting hold of dynamic mechanical properties. We can get hold of dependency on the shearing strain of the shearing modulus and hysteresis damping constant, the application for the mechanical model etc. by dynamic triaxial tests, the acceptability of maximum shearing modulus obtained from dynamic triaxial tests etc. by measurement of elastic wave velocity and dynamic strength caused by cyclic stress etc. by liquefaction tests. (author)
The buffer/container experiment: results, synthesis, issues
International Nuclear Information System (INIS)
Graham, J.; Chandler, N.A.; Dixon, D.A.; Roach, P.J.; To, T.; Wan, A.W.L.
1997-12-01
A large in-ground experiment has examined how heat affects the performance of the dense sand bentonite 'buffer' that has been proposed for use in the Canadian Nuclear Fuel Waste Management Program. The experiment was performed by Atomic Energy of Canada Limited at its Underground Research Laboratory, Lac du Bonnet, Manitoba between 1991 and 1994. The experiment placed a full-size heater representing a container of nuclear fuel waste in a 1.24-m diameter borehole filled with buffer below the floor of a room excavated at 240-m depth in granitic rock of the Canadian Shield. The buffer and surrounding rock were extensively instrumented for temperatures, total pressures, water pressures, suctions, and rock displacements. Power was provided to the heater for almost 900 days. The experiment showed that good rock conditions can be pre-selected, a borehole can be drilled, and buffer can be placed at controlled densities and water contents. The instrumentation generally worked well, and an extensive data base was successfully organized. Drying was observed in buffer close to the heater. This caused some desiccation cracking. However the cracks only extended approximately one third of the distance to the buffer-rock interface and did not form an advective pathway. Following sampling at the time of decommissioning, cracked samples of buffer were transported to the laboratory and given access to water. The hydraulic conductivities and swelling pressures of these resaturated samples were very similar to those of uncracked buffer. A good balance was achieved between the mass of water flowing into the experiment from the surrounding rock and the increased mass of water in the buffer. A good understanding was developed of the relationships between suctions, water contents, and total pressures in buffer near the buffer-rock interface. Comparisons between measurements and predictions of measured parameters show that a good understanding has been developed of the processes operating
The buffer/container experiment: results, synthesis, issues
Energy Technology Data Exchange (ETDEWEB)
Graham, J. [Univ. of Manitoba, Dept. of Civil Engineering, Winnipeg, MB (Canada); Chandler, N.A.; Dixon, D.A.; Roach, P.J.; To, T.; Wan, A.W.L
1997-12-01
A large in-ground experiment has examined how heat affects the performance of the dense sand bentonite 'buffer' that has been proposed for use in the Canadian Nuclear Fuel Waste Management Program. The experiment was performed by Atomic Energy of Canada Limited at its Underground Research Laboratory, Lac du Bonnet, Manitoba between 1991 and 1994. The experiment placed a full-size heater representing a container of nuclear fuel waste in a 1.24-m diameter borehole filled with buffer below the floor of a room excavated at 240-m depth in granitic rock of the Canadian Shield. The buffer and surrounding rock were extensively instrumented for temperatures, total pressures, water pressures, suctions, and rock displacements. Power was provided to the heater for almost 900 days. The experiment showed that good rock conditions can be pre-selected, a borehole can be drilled, and buffer can be placed at controlled densities and water contents. The instrumentation generally worked well, and an extensive data base was successfully organized. Drying was observed in buffer close to the heater. This caused some desiccation cracking. However the cracks only extended approximately one third of the distance to the buffer-rock interface and did not form an advective pathway. Following sampling at the time of decommissioning, cracked samples of buffer were transported to the laboratory and given access to water. The hydraulic conductivities and swelling pressures of these resaturated samples were very similar to those of uncracked buffer. A good balance was achieved between the mass of water flowing into the experiment from the surrounding rock and the increased mass of water in the buffer. A good understanding was developed of the relationships between suctions, water contents, and total pressures in buffer near the buffer-rock interface. Comparisons between measurements and predictions of measured parameters show that a good understanding has been developed of the processes
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....
International comparison of observation-specific spatial buffers
DEFF Research Database (Denmark)
Frank, Lawrence D; Fox, Eric H; Ulmer, Jared M
2017-01-01
the relative differences in resulting explanatory power on self-reported physical activity outcomes. BEMs were developed in five countries using 'sausage,' 'detailed-trimmed,' and 'detailed,' network buffers at a distance of 1 km around participant household addresses (n = 5883). RESULTS: BEM values were...... significantly different (p trimmed buffer comparisons and 89% of sausage versus detailed network buffer comparisons. Results showed that BEM coefficients in physical activity models did not differ significantly across buffering methods, and in most cases BEM...
Challenges in higher order mode Raman amplifiers
DEFF Research Database (Denmark)
Rottwitt, Karsten; Nielsen, Kristian; Friis, Søren Michael Mørk
2015-01-01
A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed......A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed...
Directory of Open Access Journals (Sweden)
Anne Galarneau
2016-04-01
Full Text Available Silica monoliths featuring either mesopores or flow-through macropores and mesopores in their skeleton are prepared by combining spinodal phase separation and sol-gel condensation. The macroporous network is first generated by phase separation in acidic medium in the presence of polyethyleneoxides while mesoporosity is engineered in a second step in alkaline medium, possibly in the presence of alkylammonium cations as surfactants. The mesoporous monoliths, also referred as aerogels, are obtained in the presence of alkylpolyethylene oxides in acidic medium without the use of supercritical drying. The impact of the experimental conditions on pore architecture of the monoliths regarding the shape, the ordering, the size and the connectivity of the mesopores is comprehensively discussed based on a critical appraisal of the different models used for textural analysis.
Honma, K.; Handa, K.; Akinaga, W.; Doi, M.; Matsuzaki, O.
This paper describes the design and the performance of the S-band low noise amplifier and the S-band high power amplifier that have been developed for the Usuda Deep Space Station of the Institute of Space and Astronautical Science (ISAS), Japan. The S-band low noise amplifier consists of a helium gas-cooled parametric amplifier followed by three-stage FET amplifiers and has a noise temperature of 8 K. The high power amplifier is composed of two 28 kW klystrons, capable of transmitting 40 kW continuously when two klystrons are combined. Both subsystems are operating quite satisfactorily in the tracking of Sakigake and Suisei, the Japanese interplanetary probes for Halley's comet exploration, launched by ISAS in 1985.
The Health Risk Assessment of Pb and Cr leachated from fly ash monolith landfill
International Nuclear Information System (INIS)
Hung, Ming-Lung; Wu, Sheng-Yao; Chen, Yen-Chuan; Shih, Hsiu-Ching; Yu, Yue-Hwa; Ma, Hwong-wen
2009-01-01
As of 2004, nearly two hundred thousand tons of fly ash monoliths are created each year in Taiwan to confine heavy metals for reducing the leaching quantity by precipitation. However, due to abnormal monolith fracture, poorly liner quality or exceeding usage over designed landfill capacity, serious groundwater pollution of the landfills has been reported. This research focuses on Pb and Cr leaching from monolithic landfill to assess the risk of groundwater pollution in the vicinity. The methodology combines water budget simulations using HELP model with fate and risk simulations using MMSOILS model for 5 kinds of landfill structures and 2 types of leaching models, and calculates the risk distribution over 400 grids in the down gradient direction of groundwater. The results demonstrated that the worst liner quality will cause the largest risk and the most significant exposure pathway is groundwater intake, which accounted for 98% of the total risk. Comparing Pb and Cr concentrations in the groundwater with the drinking water standards, only 14.25% of the total grids are found to be under 0.05 mg/L of Pb, and over 96.5% of the total grids are in the safety range of Cr. It indicates that Pb leaching from fly ash monolithic landfills may cause serious health risks. Without consideration of the parameters uncertainty, the cancer and noncancer risk of Pb with the sanitary landfill method was 4.23E-07 and 0.63, respectively, both under acceptable levels. However, by considering the parameters uncertainty, the non-carcinogenic risk of Pb became 1.43, exceeding the acceptable level. Only under the sealed landfill method was the hazard quotient below 1. It is important to use at least the sealed landfill for fly ash monoliths containing lead to effectively reduce health risks.
Yi, Dong Kee
2008-09-01
A reverse microemulsion technique has been used to synthesize quantum dot nanocomposites within a SiO2 surface coating. With this approach, the unique optical properties of the CdSe/ZnS quantum dots were preserved. CdSe/ZnS/SiO2 nanoparticles were homogeneously distributed in a tetramethyl orthosilicate ethanol solution and gelation process was initiated within a 10 min, and was left over night at room temperature and dried fully to achieve a solid SiO, monolith. The resulting monolith was transparent and fluorescent under ultraviolet (UV) lamp. Moreover the monolith produced was crack-free. Further studies on the photo stability of the monolith were performed using a high power UV LED device. Remarkably, quantum dots in the SiO, monolith showed better photo stability compared with those dispersed in a polymer matrix.
Multi-Buffer Simulations for Trace Language Inclusion
Directory of Open Access Journals (Sweden)
Milka Hutagalung
2016-09-01
Full Text Available We consider simulation games played between Spoiler and Duplicator on two Büchi automata in which the choices made by Spoiler can be buffered by Duplicator in several buffers before she executes them on her structure. We show that the simulation games are useful to approximate the inclusion of trace closures of languages accepted by finite-state automata, which is known to be undecidable. We study the decidability and complexity and show that the game with bounded buffers can be decided in polynomial time, whereas the game with one unbounded and one bounded buffer is highly undecidable. We also show some sufficient conditions on the automata for Duplicator to win the game (with unbounded buffers.
Small signal microwave amplifier design
Grosch, Theodore
2000-01-01
This book explains techniques and examples for designing stable amplifiers for high-frequency applications in which the signal is small and the amplifier circuit is linear. An in-depth discussion of linear network theory provides the foundation needed to develop actual designs. Examples throughout the book will show you how to apply the knowledge gained in each chapter leading to the complex design of low noise amplifiers. Many exercises at the end of each chapter will help students to practice their skills. The solutions to these design problems are available in an accompanying solutions book
Heat conductivity of buffer materials
International Nuclear Information System (INIS)
Boergesson, L.; Fredrikson, Anders; Johannesson, L.E.
1994-11-01
The report deals with the thermal conductivity of bentonite based buffer materials. An improved technique for measuring the thermal conductivity of buffer materials is described. Measurements of FLAC calculations applying this technique have led to a proposal of how standardized tests should be conducted and evaluated. The thermal conductivity of bentonite with different void ratio and degree of water saturation has been determined in the following different ways: * Theoretically according to three different investigations by other researchers. * Laboratory measurements with the proposed method. * Results from back-calculated field tests. Comparison and evaluation showed that these results agreed very well, when the buffer material was almost water saturated. However, the influence of the degree of saturation was not very well predicted with the theoretical methods. Furthermore, the field tests showed that the average thermal conductivity in situ of buffer material (compacted to blocks) with low degree of water saturation was lower than expected from laboratory tests. 12 refs, 29 figs, 11 tabs
Reliability Analysis and Optimal Design of Monolithic Vertical Wall Breakwaters
DEFF Research Database (Denmark)
Sørensen, John Dalsgaard; Burcharth, Hans F.; Christiani, E.
1994-01-01
Reliability analysis and reliability-based design of monolithic vertical wall breakwaters are considered. Probabilistic models of the most important failure modes, sliding failure, failure of the foundation and overturning failure are described . Relevant design variables are identified...
THE BUFFER CAPACITY OF AIRWAY EPITHELIAL SECRETIONS
Directory of Open Access Journals (Sweden)
Dusik eKim
2014-06-01
Full Text Available The pH of airway epithelial secretions influences bacterial killing and mucus properties and is reduced by acidic pollutants, gastric reflux, and respiratory diseases such as cystic fibrosis (CF. The effect of acute acid loads depends on buffer capacity, however the buffering of airway secretions has not been well characterized. In this work we develop a method for titrating micro-scale (30 µl volumes and use it to study fluid secreted by the human airway epithelial cell line Calu-3, a widely used model for submucosal gland serous cells. Microtitration curves revealed that HCO3- is the major buffer. Peak buffer capacity (β increased from 17 to 28 mM/pH during forskolin stimulation, and was reduced by >50% in fluid secreted by cystic fibrosis transmembrane conductance regulator (CFTR-deficient Calu-3 monolayers, confirming an important role of CFTR in HCO3- secretion. Back-titration with NaOH revealed non-volatile buffer capacity due to proteins synthesized and released by the epithelial cells. Lysozyme and mucin concentrations were too low to buffer Calu-3 fluid significantly, however model titrations of porcine gastric mucins at concentrations near the sol-gel transition suggest that mucins may contribute to the buffer capacity of ASL in vivo. We conclude that CFTR-dependent HCO3- secretion and epithelially-derived proteins are the predominant buffers in Calu-3 secretions.
Long-lived monolithic micro-optics for multispectral GRIN applications.
Lepicard, Antoine; Bondu, Flavie; Kang, Myungkoo; Sisken, Laura; Yadav, Anupama; Adamietz, Frederic; Rodriguez, Vincent; Richardson, Kathleen; Dussauze, Marc
2018-05-09
The potential for realizing robust, monolithic, near-surface refractive micro-optic elements with long-lived stability is demonstrated in visible and infrared transmitting glasses capable of use in dual band applications. Employing an enhanced understanding of glass chemistry and geometric control of mobile ion migration made possible with electrode patterning, flat, permanent, thermally-poled micro-optic structures have been produced and characterized. Sub-surface (t~5-10 µm) compositional and structural modification during the poling process results in formation of spatially-varying refractive index profiles, exhibiting induced Δn changes up to 5 × 10 -2 which remain stable for >15 months. The universality of this approach applied to monolithic vis-near infrared [NIR] oxide and NIR-midwave infrared [MIR] chalcogenide glass materials is demonstrated for the first time. Element size, shape and gradient profile variation possible through pattern design and fabrication is shown to enable a variety of design options not possible using other GRIN process methodologies.
Kim, Hee-Kyung; Kim, Sung-Hun; Lee, Jai-Bong; Ha, Seung-Ryong
2016-06-01
Surface polishing or glazing may increase the appearance of depth of monolithic zirconia restorations. The purpose of this in vitro study was to investigate the effects of surface treatments on the translucency, opalescence, and surface texture of dental monolithic zirconia ceramics. Forty-five monolithic zirconia specimens (16.3×16.4×2.0 mm) were divided into groups I to V, according to the number of colorings each received. Each group was then divided into 3 subgroups (n=3) according to the surface treatment: N=no treatment; P=polished; and G=glazed. CIElab color coordinates were obtained relative to D65 on a reflection spectrophotometer. The translucency parameter (TP) and opalescence parameter (OP) were calculated. One specimen per subgroups I and V was selected for evaluation of surface roughness (Ra) and was examined with scanning electron microscopy (SEM). Data were analyzed with 2-way ANOVA and pairwise comparisons (α=.05). Statistical powers were verified to evaluate results (α=.05). The interaction effects of surface treatments combined with the number of colorings were significant for TP, OP, and Ra (P.05), whereas glazing significantly decreased OP and Ra in most groups. SEM images demonstrated that surface treatments affected the surface texture of monolithic zirconia ceramics. Surface treatments combined with coloring strongly affect the surface texture of dental monolithic zirconia ceramics. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Wang, Hongwei; Ou, Junjie; Lin, Hui; Liu, Zhongshan; Huang, Guang; Dong, Jing; Zou, Hanfa
2014-11-07
Two kinds of hybrid monolithic columns were prepared by using methacrylate epoxy cyclosiloxane (epoxy-MA) as functional monomer, containing three epoxy moieties and one methacrylate group. One column was in situ fabricated by ring-opening polymerization of epoxy-MA and 1,10-diaminodecane (DAD) using a porogenic system consisting of isopropanol (IPA), H2O and ethanol at 65°C for 12h. The other was prepared by free radical polymerization of epoxy-MA and ethylene dimethacrylate (EDMA) using 1-propanol and 1,4-butanediol as the porogenic solvents at 60°C for 12h. Two hybrid monoliths were investigated on the morphology and chromatographic assessment. Although two kinds of monolithic columns were prepared with epoxy-MA, their morphologies looked rather different. It could be found that the epoxy-MA-DAD monolith possessed higher column efficiencies (25,000-34,000plates/m) for the separation of alkylbenzenes than the epoxy-MA-EDMA monolith (12,000-13,000plates/m) in reversed-phase nano-liquid chromatography (nano-LC). Depending on the remaining epoxy or methacrylate groups on the surface of two pristine monoliths, the epoxy-MA-EDMA monolith could be easily modified with 1-octadecylamine (ODA) via ring-opening reaction, while the epoxy-MA-DAD monolith could be modified with stearyl methacrylate (SMA) via free radical reaction. The chromatographic performance for the separation of alkylbenzenes on SMA-modified epoxy-MA-DAD monolith was remarkably improved (42,000-54,000 plates/m) when compared with that on pristine epoxy-MA-DAD monolith, while it was not obviously enhanced on ODA-modified epoxy-MA-EDMA monolith when compared with that on pristine epoxy-MA-EDMA monolith. The enhancement of the column efficiency of epoxy-MA-DAD monolith after modification might be ascribed to the decreased mass-transfer resistence. The two kinds of hybrid monoliths were also applied for separations of six phenols and seven basic compounds in nano-LC. Copyright © 2014 Elsevier B.V. All
Qiao, Xiaoqiang; Zhang, Niu; Han, Manman; Li, Xueyun; Qin, Xinying; Shen, Shigang
2017-03-01
A novel periodic imidazolium-bridged hybrid monolithic column was developed. With diene imidazolium ionic liquid 1-allyl-3-vinylimidazolium bromide as both cross-linker and organic functionalized reagent, a new periodic imidazolium-bridged hybrid monolithic column was facilely prepared in capillary with homogeneously distributed cationic imidazolium by a one-step free-radical polymerization with polyhedral oligomeric silsesquioxane methacryl substituted. The successful preparation of the new column was verified by Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analysis, and surface area analysis. Most interestingly, the bonded amount of 1-allyl-3-vinylimidazolium bromide of the new column is three times higher than that of the conventional imidazolium-embedded hybrid monolithic column and the specific surface area of the column reached 478 m 2 /g. The new column exhibited high stability, excellent separation efficiency, and enhanced separation selectivity. The column efficiency reached 151 000 plates/m for alkylbenzenes. Furthermore, the new column was successfully used for separation of highly polar nucleosides and nucleic acid bases with pure water as mobile phase and even bovine serum albumin tryptic digest. All these results demonstrate the periodic imidazolium-bridged hybrid monolithic column is a good separation media and can be used for chromatographic separation of small molecules and complex biological samples with high efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Roper, Kimberley A; Berry, Malcolm B; Ley, Steven V
2013-01-01
The application of a monolithic form of triphenylphosphine to the Ramirez gem-dibromoolefination reaction using flow chemistry techniques is reported. A variety of gem-dibromides were synthesised in high purity and excellent yield following only removal of solvent and no further off-line purification. It is also possible to perform the Appel reaction using the same monolith and the relationship between the mechanisms of the two reactions is discussed.
Gough, Dara Van; Huber, Dale L.; Bunker, Bruce C.; Roberts, Mark E.
2017-01-24
A programmable pH buffer comprises a copolymer that changes pK.sub.a at a lower critical solution temperature (LCST) in water. The copolymer comprises a thermally programmable polymer that undergoes a hydrophobic-to-hydrophilic phase change at the LCST and an electrolytic polymer that exhibits acid-base properties that are responsive to the phase change. The programmable pH buffer can be used to sequester CO.sub.2 into water.
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.
Jones, Brad H; Lodge, Timothy P
2009-02-11
Nanoporous ceramic with a unique pore structure was derived from an all-hydrocarbon polymeric bicontinuous microemulsion (BmuE). The BmuE was designed to allow facile removal of one phase, resulting in a nanoporous polymer monolith with BmuE-like structure. The pores were filled with a commercially available, polymeric precursor to nonoxide, Si-based ceramics. Pyrolysis resulted in a monolith of nanoporous ceramic, stable to at least 1000 degrees C, with a BmuE-like pore structure. The pore structure is disordered and 3-D continuous. Microscopy and gas sorption measurements suggest a well-defined pore size distribution spanning roughly 60-100 nm, sizes previously unattainable through related techniques.
DEFF Research Database (Denmark)
Jeppesen, Palle
1997-01-01
Noise in optical amplifiers is discussed on the basis of photons and electromagntic fields. Formulas for quantum noise from spontaneous emission, signal-spontaneous beat noise and spontaneous-spontaneous beat noise are derived.......Noise in optical amplifiers is discussed on the basis of photons and electromagntic fields. Formulas for quantum noise from spontaneous emission, signal-spontaneous beat noise and spontaneous-spontaneous beat noise are derived....
A buffer overflow detection based on inequalities solution
International Nuclear Information System (INIS)
Xu Guoai; Zhang Miao; Yang Yixian
2007-01-01
A new buffer overflow detection model based on Inequalities Solution was designed, which is based on analyzing disadvantage of the old buffer overflow detection technique and successfully converting buffer overflow detection to Inequalities Solution. The new model can conquer the disadvantage of the old technique and improve efficiency of buffer overflow detection. (authors)
Zhang, Doudou; Zhang, Qian; Bai, Ligai; Han, Dandan; Liu, Haiyan; Yan, Hongyuan
2018-05-01
An ionic-liquid-based polymer monolithic column was synthesized by free radical polymerization within the confines of a stainless-steel column (50 mm × 4.6 mm id). In the processes, ionic liquid and stearyl methacrylate were used as dual monomers, ethylene glycol dimethacrylate as the cross-linking agent, and polyethylene glycol 200 and isopropanol as co-porogens. Effects of the prepolymerization solution components on the properties of the resulting monoliths were studied in detail. Scanning electron microscopy, nitrogen adsorption-desorption measurements, and mercury intrusion porosimetry were used to investigate the morphology and pore size distribution of the prepared monoliths, which showed that the homemade ionic-liquid-based monolith column possessed a relatively uniform macropore structure with a total macropore specific surface area of 44.72 m 2 /g. Compared to a non-ionic-liquid-based monolith prepared under the same conditions, the ionic-liquid-based monolith exhibited excellent selectivity and high performance for separating proteins from complex biosamples, such as egg white, snailase, bovine serum albumin digest solution, human plasma, etc., indicating promising applications in the fractionation and analysis of proteins from the complex biosamples in proteomics research. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Ito, Kazuaki; Nomura, Ryosuke; Fujii, Takuya; Tanaka, Masahito; Tsumura, Tomoaki; Shibata, Hiroyuki; Hirokawa, Takeshi
2012-11-01
A method was developed for determination of inorganic anions, including nitrite (NO(2)(-)), nitrate (NO(3)(-)), bromide (Br(-)), and iodide (I(-)), in seawater by ion chromatography (IC). The IC system used two dilauryldimethylammonium bromide (DDAB)-coated monolithic ODS columns (50 × 4.6 mm i.d. and 100 × 4.6 mm i.d.) connected in series for separation of the ions. Aqueous NaCl (0.5 mol/L; flow rate, 3 mL/min) containing 5 mmol/L phosphate buffer (pH 5) was used as the eluent, and detection was with a UV detector at 225 nm. The monolithic ODS columns were coated and equilibrated with a 1-mmol/L DDAB solution (in H(2)O/methanol, 90:10 v/v). The hydrophilic ions (NO(2)(-), NO(3)(-), and Br(-)) were separated within 3 min and the retention time of I(-) was 16 min. No interferences from matrix ions, such as chloride and sulfate ions, were observed in 35 ‰ artificial seawater. The detection limits were 0.6 μg/L for NO(2)(-), 1.1 μg/L for NO(3)(-), 70 μg/L for Br(-), and 1.6 μg/L for I(-) with a 200-μL sample injection. The performance of the coated columns was maintained without addition of DDAB in the eluent. The IC system was successfully applied to real seawater samples with recovery rates of 94-108 % for all ions.
Amplified spontaneous emissions in a high-gain laser amplifier
International Nuclear Information System (INIS)
Osada, Hidenori; Gamo, Hideya.
1978-01-01
The gain and line-narrowing of the amplified spontaneous emissions(ASE) in a partially homogeneous high-gain Xe 3.51 μm laser amplifier were studied theoretically and experimentally with emphasis of saturation effect. The unidirectionally travelling ASE was generated by conveniently using optical isolators and used as a broadband radiation source. It has properties of 10 μW/mm 2 in intensity with fluctuation of less than 1% in 5 hours, 43.5 MHz of the linewidth and 1.0 x 10 -3 radians of beam divergence. The measured saturation intensity was 4.85 μW/mm 2 and a small signal gain was 0.1 cm -1 . The theoretical prediction of the line-narrowing shows reasonablly good agreement with the measured one. (author)
Dual-range linearized transimpedance amplifier system
Wessendorf, Kurt O.
2010-11-02
A transimpedance amplifier system is disclosed which simultaneously generates a low-gain output signal and a high-gain output signal from an input current signal using a single transimpedance amplifier having two different feedback loops with different amplification factors to generate two different output voltage signals. One of the feedback loops includes a resistor, and the other feedback loop includes another resistor in series with one or more diodes. The transimpedance amplifier system includes a signal linearizer to linearize one or both of the low- and high-gain output signals by scaling and adding the two output voltage signals from the transimpedance amplifier. The signal linearizer can be formed either as an analog device using one or two summing amplifiers, or alternately can be formed as a digital device using two analog-to-digital converters and a digital signal processor (e.g. a microprocessor or a computer).
Detection of Non-Amplified Genomic DNA
Corradini, Roberto
2012-01-01
This book offers a state-of-the-art overview on non amplified DNA detection methods and provides chemists, biochemists, biotechnologists and material scientists with an introduction to these methods. In fact all these fields have dedicated resources to the problem of nucleic acid detection, each contributing with their own specific methods and concepts. This book will explain the basic principles of the different non amplified DNA detection methods available, highlighting their respective advantages and limitations. The importance of non-amplified DNA sequencing technologies will be also discussed. Non-amplified DNA detection can be achieved by adopting different techniques. Such techniques have allowed the commercialization of innovative platforms for DNA detection that are expected to break into the DNA diagnostics market. The enhanced sensitivity required for the detection of non amplified genomic DNA has prompted new strategies that can achieve ultrasensitivity by combining specific materials with specifi...
Magnetorheological elastomer and its application on impact buffer
International Nuclear Information System (INIS)
Fu, J; Yu, M; Zhu, L X; Dong, X M
2013-01-01
In this study, a new magnetorheological elastomer (MRE) based buffer is proposed and its vibration isolation performance is investigated. The MRE buffer with a compact structure is first designed in order to accomplish the maximization of the variable stiffness range. The working characteristics of the MRE buffer are then measured and the model of MRE is established. On the basis of the experimental data, the control model of the MRE buffer is also formulated. A two-degree-of-freedom dynamic model with an MRE buffer is then developed. An intelligent control strategy, human simulated intelligent control (HSIC), is proposed to reduce the impact during the drop crash. Finally, the proposed MRE buffer and controller are validated numerically and experimentally. The results show that the proposed MRE buffer and the control strategy can reduce the impact acceleration effectively.
Is there a role for amplifiers in sexual selection?
Gualla, Filippo; Cermelli, Paolo; Castellano, Sergio
2008-05-21
The amplifier hypothesis states that selection could favour the evolution of traits in signallers that improve the ability of receivers to extract honest information from other signals or cues. We provide a formal definition of amplifiers based on the receiver's mechanisms of signal perception and we present a game-theoretical model in which males advertise their quality and females use sequential-sampling tactics to choose among prospective mates. The main effect of an amplifier on the female mating strategy is to increase her mating threshold, making the female more selective as the effectiveness of the amplifier increases. The effects of the amplifier on male advertising strategy depends both on the context and on the types of the amplifier involved. We consider two different contexts for the evolution of amplifiers (when the effect of amplifiers is on signals and when it is on cues) and two types of amplifiers (the 'neutral amplifier', when it improves quality assessment without altering male attractiveness, and the 'attractive amplifier', when it improves both quality assessment and male attractiveness). The game-theoretical model provides two main results. First, neutral and attractive amplifiers represent, respectively, a conditional and an unconditional signalling strategy. In fact, at the equilibrium, neutral amplifiers are displayed only by males whose advertising level lays above the female acceptance threshold, whereas attractive amplifiers are displayed by all signalling males, independent of their quality. Second, amplifiers of signals increase the differences in advertising levels between amplifying and not-amplifying males, but they decrease the differences within each group, so that the system converges towards an 'all-or-nothing' signalling strategy. By applying concepts from information theory, we show that the increase in information transfer at the perception level due to the amplifier of signals is contrasted by a decrease in information
An Implantable CMOS Amplifier for Nerve Signals
DEFF Research Database (Denmark)
Nielsen, Jannik Hammel; Lehmann, Torsten
2001-01-01
In this paper, a low noise high gain CMOS amplifier for minute nerve signals is presented. By using a mixture of weak- and strong inversion transistors, optimal noise suppression in the amplifier is achieved. A continuous-time offset-compensation technique is utilized in order to minimize impact...... on the amplifier input nodes. The method for signal recovery from noisy nerve signals is presented. A prototype amplifier is realized in a standard digital 0.5 μm CMOS single poly, n-well process. The prototype amplifier features a gain of 80 dB over a 3.6 kHz bandwidth, a CMRR of more than 87 dB and a PSRR...
Operational amplifiers theory and design
Huijsing, Johan
2017-01-01
This proven textbook guides readers to a thorough understanding of the theory and design of operational amplifiers (OpAmps). The core of the book presents systematically the design of operational amplifiers, classifying them into a periodic system of nine main overall configurations, ranging from one gain stage up to four or more stages. This division enables circuit designers to recognize quickly, understand, and choose optimal configurations. Characterization of operational amplifiers is given by macro models and error matrices, together with measurement techniques for their parameters. Definitions are given for four types of operational amplifiers depending on the grounding of their input and output ports. Many famous designs are evaluated in depth, using a carefully structured approach enhanced by numerous figures. In order to reinforce the concepts introduced and facilitate self-evaluation of design skills, the author includes problems with detailed solutions, as well as simulation exercises. Provides te...
Directory of Open Access Journals (Sweden)
Andrzej Szczurek
2018-05-01
Full Text Available Electromagnetic shielding is a topic of high importance for which lightweight materials are highly sought. Porous carbon materials can meet this goal, but their structure needs to be controlled as much as possible. In this work, cellular carbon monoliths of well-defined porosity and cell size were prepared by a template method, using sacrificial paraffin spheres as the porogen and resorcinol-formaldehyde (RF resin as the carbon precursor. Physicochemical studies were carried out for investigating the conversion of RF resin into carbon, and the final cellular monoliths were investigated in terms of elemental composition, total porosity, surface area, micropore volumes, and micro/macropore size distributions. Electrical and electromagnetic (EM properties were investigated in the static regime and in the Ka-band, respectively. Due to the phenolic nature of the resin, the resultant carbon was glasslike, and the special preparation protocol that was used led to cellular materials whose cell size increased with density. The materials were shown to be relevant for EM shielding, and the relationships between those properties and the density/cell size of those cellular monoliths were elucidated.
Zhao, Hongyan; Wang, Yizhou; Cheng, Heyong; Wang, Yuanchao
2017-08-01
Single-walled carbon nanohorns have received great interest for their unique properties and diverse potential applications. Herein, we demonstrated the feasibility of single-walled carbon nanohorns incorporated poly(styrene-divinylbenzene) monolith as the stationary phase for capillary electrochromatography, which were prepared by one-step in situ copolymerization. Single-walled carbon nanohorns were dispersed in styrene to give a stable and homogeneous suspension. The monolithic column gave effective separation for a wide range of aromatic compounds, which was based on hydrophobicity and π-π electrostatic stacking of single-walled carbon nanohorns. The precisions of migration time and peak area varied in the ranges of 1.4-1.9% for intraday trials and 1.7-3.5% for interday trials, and 3.2-6.7% for intraday trials and 4.1-7.4% for interday trials, and 3.6-7.2% for inter-column trials and 5.2-21.3% for inter-column trials, respectively, indicating the good reproducibility of single-walled carbon nanohorns embedded monolithic columns. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Audo, Kevin; Alouini, Mehdi
2018-03-01
An absorption mechanism based on second-harmonic generation (SHG) is successfully implemented as a buffer reservoir in a solid-state Er,Yb:Glass laser emitting at the telecom wavelength. We show that a slight absorption mechanism based on SHG rate conversion of 0.016% using a beta barium borate crystal enables the canceling out of the excess intensity noise at the relaxation oscillation frequency, i.e., 35 dB reduction, as well as canceling the amplified spontaneous emission beating at the free spectral range resonances of the laser lying in the gigahertz range. Laser robustness is discussed.
Wideband Low Noise Amplifiers Exploiting Thermal Noise Cancellation
Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram
2005-01-01
Low Noise Amplifiers (LNAs) are commonly used to amplify signals that are too weak for direct processing for example in radio or cable receivers. Traditionally, low noise amplifiers are implemented via tuned amplifiers, exploiting inductors and capacitors in resonating LC-circuits. This can render
Energy Technology Data Exchange (ETDEWEB)
Lin, Shu-Ling; Wu, Yu-Ru; Lin, Tzuen-Yeuan; Fuh, Ming-Ren, E-mail: msfuh@scu.edu.tw
2015-04-29
Highlights: • Methacrylic acid (MAA) was used to increase hydrophilicity of polymeric monoliths. • Fast separation of phenol derivatives was achieved in 5 min using MAA-incorporated column. • Separations of aflatoxins and phenicol antibiotics were achieved using MAA-incorporated column. - Abstract: In this study, methacrylic acid (MAA) was incorporated with alkyl methacrylates to increase the hydrophilicity of the synthesized ethylene dimethacrylate-based (EDMA-based) monoliths for separating polar small molecules by capillary LC analysis. Different alkyl methacrylate–MAA ratios were investigated to prepare a series of 30% alkyl methacrylate–MAA–EDMA monoliths in fused-silica capillaries (250-μm i.d.). The porosity, permeability, and column efficiency of the synthesized MAA-incorporated monolithic columns were characterized. A mixture of phenol derivatives is employed to evaluate the applicability of using the prepared monolithic columns for separating small molecules. Fast separation of six phenol derivatives was achieved in 5 min with gradient elution using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. In addition, the effect of acetonitrile content in mobile phase on retention factor and plate height as well as the plate height-flow velocity curves were also investigated to further examine the performance of the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column. Moreover, the applicability of prepared polymer-based monolithic column for potential food safety applications was also demonstrated by analyzing five aflatoxins and three phenicol antibiotics using the selected poly(lauryl methacrylate-co-MAA-co-EDMA) monolithic column.
Park, Sin Young; Cheong, Won Jo
2015-09-01
This study introduces a preparation method for polymer-encased monolith frits with improved durability for liquid chromatography columns. The inner surface of the polyether ether ketone tubing is pretreated with sulfuric acid in the presence of catalysts (vanadium oxide and sodium sulfate). The tubing was rinsed with water and acetone, flushed with nitrogen, and treated with glycidyl methacrylate. After washing, the monolith reaction mixture composed of lauryl methacrylate, ethylene glycol dimethacrylate, initiator, and porogenic solvent was filled in the tubing and subjected to in situ polymerization. The tubing was cut into thin slices and used as frits for microcolumns. To check their durability, the frit slices were placed in a vial and a heavy impact was applied on the vial by a vortex mixer for various periods. The frits made in the presence of catalysts were found to be more durable than those made without catalysts. Furthermore, when the monolith-incorporated tubing was used as a chromatography column, the column prepared in the presence of catalysts resulted in a better separation efficiency. The separation performance of the columns installed with the polyether ether ketone encased monolith frits was comparable to that of the columns installed with the commercial stainless-steel screen frits. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The thermodynamic-buffer enzymes.
Stucki, J W
1980-08-01
Oxidative phosphorylation operates at optimal efficiency if and only if the condition of conductance matching L33/L11 = square root 1-q2 is fulfilled. In this relation L11 is the phenomenological conductance of phosphorylation, L33 the phenomenological conductance of the load, i.e. the irreversible ATP-utilizing processes in the cell, and q the degree of coupling of oxidative phosphorylation driven by respiration. Since during short time intervals L11 and q are constant whereas L33 fluctuates in the cell, oxidative phosphorylation would only rarely operate at optimal efficiency due to violation of conductance matching. This paper demonstrates that the reversible ATP-utilizing reaction catalyzed by adenylate kinase can effectively compensate deviations from conductance matching in the presence of a fluctuating L33 and hence allows oxidative phosphorylation to operate at optimal efficiency in the cell. Since the adenylate kinase reaction was found to buffer a thermodynamic potential, i.e. the phosphate potential, this finding was generalized to the concept of thermodynamic buffering. The thermodynamic buffering ability of the adenylate kinase reaction was demonstrated by experiments with incubated rat-liver mitochondria. Considerations of changes introduced in the entropy production by the adenylate kinase reaction allowed to establish the theoretical framework for thermodynamic buffering. The ability of thermodynamic buffering to compensate deviations from conductance matching in the presence of fluctuating loads was demonstrated by computer simulations. The possibility of other reversible ATP-utilizing reactions, like the ones catalyzed by creatine kinase and arginine kinase, to contribute to thermodynamic buffering is discussed. Finally, the comparison of the theoretically calculated steady-stae cytosolic adenine nucleotide concentrations with experimental data from perfused livers demonstrated that in livers from fed rats conductance matching is fulfilled on a
Martinović, Tamara; Josić, Djuro
2017-11-01
The experiences in the production and application of polymethacrylate-based monolithic supports, since their development almost thirty years ago, are presented. The main driving force for the development of new chromatographic supports was the necessity for the isolation and separation of physiologically active biopolymers and their use for therapeutic purposes. For this sake, a development of a method for fast separation, preventing denaturation and preserving their biological activity was necessary. Development of polysaccharide-based supports, followed by the introduction of polymer-based chromatographic media, is shortly described. This development was followed by the advances in monolithic media that are now used for both large- and small-scale separation of biopolymers and nanoparticles. Finally, a short overview is given about the applications of monoliths for sample displacement chromatography, resulting in isolation of physiologically active biomolecules, such as proteins, protein complexes, and nucleic acid, as well as high-throughput sample preparation for proteomic investigations. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
International Nuclear Information System (INIS)
Kaanta, Bradley C; Zhang, Xin; Chen, Hua
2010-01-01
The monolithic integration of a high sensitivity detector with a gas chromatography (GC) separation column creates many potential advantages over the discrete components of a traditional chromatography system. In miniaturized high-speed GC systems, component interconnections can cause crucial errors and loss of fidelity during detection and analysis. A monolithically integrated device would eliminate the need to create helium-tight interconnections, which are bulky and labor intensive. Additionally, batch fabrication of integrated devices that no longer require expensive and fragile detectors can decrease the cost of micro GC systems through economies of scale. We present the design, fabrication and operation of a monolithic GC separation column and detector. Our device is able to separate nitrogen, methane and carbon dioxide within 30 s. This method of device integration could be applied to the existing wealth of column geometries and chemistries designed for specialized applications.
DEFF Research Database (Denmark)
Burcharth, Hans F.; Christiani, Erik; Sørensen, John Dalsgaard
1995-01-01
The main object is to present a set of calibrated partial coefficients for monolithic vertical breakwater failure modes. A preliminary design of the monolithic breakwater will be considered, which will be designed from existing partial coefficients, documented in Eurocode 7 (1994). From this desi...
Phase noise in RF and microwave amplifiers.
Boudot, Rodolphe; Rubiola, Enrico
2012-12-01
Understanding amplifier phase noise is a critical issue in many fields of engineering and physics, such as oscillators, frequency synthesis, telecommunication, radar, and spectroscopy; in the emerging domain of microwave photonics; and in exotic fields, such as radio astronomy, particle accelerators, etc. Focusing on the two main types of base noise in amplifiers, white and flicker, the power spectral density of the random phase φ(t) is Sφ(f) = b(0) + b(-1)/f. White phase noise results from adding white noise to the RF spectrum in the carrier region. For a given RF noise level, b(0) is proportional to the reciprocal of the carrier power P(0). By contrast, flicker results from a near-dc 1/f noise-present in all electronic devices-which modulates the carrier through some parametric effect in the semiconductor. Thus, b(-1) is a parameter of the amplifier, constant in a wide range of P(0). The consequences are the following: Connecting m equal amplifiers in parallel, b(-1) is 1/m times that of one device. Cascading m equal amplifiers, b(-1) is m times that of one amplifier. Recirculating the signal in an amplifier so that the gain increases by a power of m (a factor of m in decibels) as a result of positive feedback (regeneration), we find that b(-1) is m(2) times that of the amplifier alone. The feedforward amplifier exhibits extremely low b(-1) because the carrier is ideally nulled at the input of its internal error amplifier. Starting with an extensive review of the literature, this article introduces a system-oriented model which describes the phase flickering. Several amplifier architectures (cascaded, parallel, etc.) are analyzed systematically, deriving the phase noise from the general model. There follow numerous measurements of amplifiers using different technologies, including some old samples, and in a wide frequency range (HF to microwaves), which validate the theory. In turn, theory and results provide design guidelines and give suggestions for CAD and
Integration trends in monolithic power ICs: Application and technology challenges
Rose, M.; Bergveld, H.J.
2016-01-01
This paper highlights the general trend towards further monolithic integration in power applications by enabling power management and interfacing solutions in advanced CMOS nodes. The need to combine high-density digital circuits, power-management circuits, and robust interfaces in a single
International Nuclear Information System (INIS)
Lippold, H.; Foerster, I.
1980-01-01
Losses of fertilizer nitrogen by denitrification were determined in soil monoliths from two sites (loess chernozem and clay ranker). The monoliths were isolated by driving plastic pipes into the plots, and fertilized with 15 N-labelled ammonium nitrate. Emission spectrometric techniques were applied to measure the N 2 and N 2 O quantities released in the isolated atmospheric layer above the monolith. The considerable losses, especially on grassland soils (up to a maximum of 30 kg N/ha), indicate the influence of rainfalls and mean temperature at the 5 dates of sampling (end of March to mid-October). (author)
Vlakh, E G; Stepanova, M A; Korneeva, Yu M; Tennikova, T B
2016-09-01
The series of macroporous monolithic molecularly imprinted monoliths differed by pore size, column length (volume) and amount of template used for imprinting was synthesized using methacrylic acid and glycerol dimethacrylate as co-monomers and antibiotic ciprofloxacin as a template. The prepared monoliths were characterized regarding to their permeability, pore size, porosity, and resistance to the flow of a mobile phase. The surface morphology was also analyzed. The slight dependence of imprinting factor on flow rate, as well as its independence on pore size of macroporous molecularly imprinted monolithic media was observed. The column obtained at different conditions exhibited different affinity of ciprofloxacin to the imprinted sites that was characterized with Kdiss values in the range of 10(-5)-10(-4)M. The solid-phase extraction of ciprofloxacin from such biological liquids as human blood serum, human urine and cow milk serum was performed using the developed monolithic columns. In all cases, the extraction was found to be 95.0-98.6%. Additionally, the comparison of extraction of three fluoroqinolone analogues, e.g. ciprofloxacin, levofloxacin and moxifloxacin, from human blood plasma was carried out. Contrary to ciprofloxacin extracted with more than 95%, this parameter did not exceed 40% for its analogues. Copyright © 2016 Elsevier B.V. All rights reserved.
Enhanced Gain in Photonic Crystal Amplifiers
DEFF Research Database (Denmark)
Ek, Sara; Semenova, Elizaveta; Hansen, Per Lunnemann
2012-01-01
We experimentally demonstrate enhanced gain in the slow-light regime of quantum well photonic crystal amplifiers. A strong gain enhancement is observed with the increase of the group refractive index, due to light slow-down. The slow light enhancement is shown in a amplified spontaneous emission....... These results are promising for short and efficient semiconductor optical amplifiers. This effect will also benefit other devices, such as mode locked lasers....
Doped LZO buffer layers for laminated conductors
Paranthaman, Mariappan Parans [Knoxville, TN; Schoop, Urs [Westborough, MA; Goyal, Amit [Knoxville, TN; Thieme, Cornelis Leo Hans [Westborough, MA; Verebelyi, Darren T [Oxford, MA; Rupich, Martin W [Framingham, MA
2010-03-23
A laminated conductor includes a metallic substrate having a surface, a biaxially textured buffer layer supported by the surface of the substrate, the biaxially textured buffer layer comprising LZO and a dopant for mitigating metal diffusion through the LZO, and a biaxially textured conductor layer supported by the biaxially textured buffer layer.
Buffer regulation of calcium puff sequences
International Nuclear Information System (INIS)
Fraiman, Daniel; Dawson, Silvina Ponce
2014-01-01
Puffs are localized Ca 2+ signals that arise in oocytes in response to inositol 1,4,5-trisphosphate (IP 3 ). They are the result of the liberation of Ca 2+ from the endoplasmic reticulum through the coordinated opening of IP 3 receptor/channels clustered at a functional release site. The presence of buffers that trap Ca 2+ provides a mechanism that enriches the spatio–temporal dynamics of cytosolic calcium. The expression of different types of buffers along the cell's life provides a tool with which Ca 2+ signals and their responses can be modulated. In this paper we extend the stochastic model of a cluster of IP 3 R-Ca 2+ channels introduced previously to elucidate the effect of buffers on sequences of puffs at the same release site. We obtain analytically the probability laws of the interpuff time and of the number of channels that participate of the puffs. Furthermore, we show that under typical experimental conditions the effect of buffers can be accounted for in terms of a simple inhibiting function. Hence, by exploring different inhibiting functions we are able to study the effect of a variety of buffers on the puff size and interpuff time distributions. We find the somewhat counter-intuitive result that the addition of a fast Ca 2+ buffer can increase the average number of channels that participate of a puff. (paper)
Buffer regulation of calcium puff sequences.
Fraiman, Daniel; Dawson, Silvina Ponce
2014-02-01
Puffs are localized Ca(2 +) signals that arise in oocytes in response to inositol 1,4,5-trisphosphate (IP3). They are the result of the liberation of Ca(2 +) from the endoplasmic reticulum through the coordinated opening of IP3 receptor/channels clustered at a functional release site. The presence of buffers that trap Ca(2 +) provides a mechanism that enriches the spatio-temporal dynamics of cytosolic calcium. The expression of different types of buffers along the cell's life provides a tool with which Ca(2 +) signals and their responses can be modulated. In this paper we extend the stochastic model of a cluster of IP3R-Ca(2 +) channels introduced previously to elucidate the effect of buffers on sequences of puffs at the same release site. We obtain analytically the probability laws of the interpuff time and of the number of channels that participate of the puffs. Furthermore, we show that under typical experimental conditions the effect of buffers can be accounted for in terms of a simple inhibiting function. Hence, by exploring different inhibiting functions we are able to study the effect of a variety of buffers on the puff size and interpuff time distributions. We find the somewhat counter-intuitive result that the addition of a fast Ca(2 +) buffer can increase the average number of channels that participate of a puff.
Directory of Open Access Journals (Sweden)
Kimberley A. Roper
2013-09-01
Full Text Available The application of a monolithic form of triphenylphosphine to the Ramirez gem-dibromoolefination reaction using flow chemistry techniques is reported. A variety of gem-dibromides were synthesised in high purity and excellent yield following only removal of solvent and no further off-line purification. It is also possible to perform the Appel reaction using the same monolith and the relationship between the mechanisms of the two reactions is discussed.
A 60-GHz rectenna for monolithic wireless sensor tags
Gao, H.; Johannsen, U.; Matters - Kammerer, M.; Milosevic, D.; Smolders, A.B.; Roermund, van A.H.M.; Baltus, P.G.M.
2013-01-01
This paper presents the design of a 60-GHz rectenna with an on-chip antenna and rectifier in 65nm CMOS technology. The rectenna is often the bottleneck in realizing a fully-integrated monolithic wireless sensor tag. In this paper, problems of the mm-wave rectifier are discussed, and the
Chambers, Stuart D.
2011-12-15
Monolithic poly(glycidyl methacrylate-co-ethylene dimethacrylate) and poly(butyl methacrylate-co-ethylene dimethacrylate) capillary columns, which incorporate the new monomer [6,6]-phenyl-C 61-butyric acid 2-hydroxyethyl methacrylate ester, have been prepared and their chromatographic performance have been tested for the separation of small molecules in the reversed phase. While addition of the C60-fullerene monomer to the glycidyl methacrylate-based monolith enhanced column efficiency 18-fold, to 85 000 plates/m at a linear velocity of 0.46 mm/s and a retention factor of 2.6, when compared to the parent monolith, the use of butyl methacrylate together with the carbon nanostructured monomer afforded monolithic columns with an efficiency for benzene exceeding 110 000 plates/m at a linear velocity of 0.32 mm/s and a retention factor of 4.2. This high efficiency is unprecedented for separations using porous polymer monoliths operating in an isocratic mode. Optimization of the chromatographic parameters affords near baseline separation of 6 alkylbenzenes in 3 min with an efficiency of 64 000 plates/m. The presence of 1 wt % or more of water in the polymerization mixture has a large effect on both the formation and reproducibility of the monoliths. Other factors such as nitrogen exposure, polymerization conditions, capillary filling method, and sonication parameters were all found to be important in producing highly efficient and reproducible monoliths. © 2011 American Chemical Society.
Static mechanical properties of buffer material
International Nuclear Information System (INIS)
Takaji, Kazuhiko; Suzuki, Hideaki
1999-11-01
The buffer material is expected to maintain its low water permeability, self-sealing properties, radionuclides adsorption and retardation properties, thermal conductivity, chemical buffering properties, overpack supporting properties, stress buffering properties, etc. over a long period of time. Natural clay is mentioned as a material that can relatively satisfy above. Among the kinds of natural clay, bentonite when compacted is superior because (i) it has exceptionally low water permeability and properties to control the movement of water in buffer, (ii) it fills void spaces in the buffer and fractures in the host rock as it swells upon water uptake, (iii) it has the ability to exchange cations and to adsorb cationic radioelements. In order to confirm these functions for the purpose of safety assessment, it is necessary to evaluate buffer properties through laboratory tests and engineering-scale tests, and to make assessments based on the ranges in the data obtained. This report describes the procedures, test conditions, results and examinations on the buffer material of unconfined compression tests, one-dimensional consolidation tests, consolidated-undrained triaxial compression tests and consolidated-undrained triaxial creep tests that aim at getting hold of static mechanical properties. We can get hold of the relationship between the dry density and tensile stress etc. by Brazilian tests, between the dry density and unconfined compressive strength etc. by unconfined compression tests, between the consolidation stress and void ratio etc. by one-dimensional consolidation tests, the stress pass of each effective confining pressure etc. by consolidated-undrained triaxial compression tests and the axial strain rate with time of each axial stress etc. by consolidated-undrained triaxial creep tests. (author)
Optimization of protein buffer cocktails using Thermofluor.
Reinhard, Linda; Mayerhofer, Hubert; Geerlof, Arie; Mueller-Dieckmann, Jochen; Weiss, Manfred S
2013-02-01
The stability and homogeneity of a protein sample is strongly influenced by the composition of the buffer that the protein is in. A quick and easy approach to identify a buffer composition which increases the stability and possibly the conformational homogeneity of a protein sample is the fluorescence-based thermal-shift assay (Thermofluor). Here, a novel 96-condition screen for Thermofluor experiments is presented which consists of buffer and additive parts. The buffer screen comprises 23 different buffers and the additive screen includes small-molecule additives such as salts and nucleotide analogues. The utilization of small-molecule components which increase the thermal stability of a protein sample frequently results in a protein preparation of higher quality and quantity and ultimately also increases the chances of the protein crystallizing.
BUFFER CAPACITY IN HETEROGENEOUS MULTICOMPONENT SYSTEMS. REVIEW
Directory of Open Access Journals (Sweden)
Oxana Spinu
2015-12-01
Full Text Available The quantitative basis of the theory of buffer properties for two-phase acid-base buffer systems and for multicomponent heterogeneous systems has been derived. The analytical equations with respect to all components for diverse multicomponent systems were deduced. It has been established, that the buffer capacities of components are mutually proportional.
Buffer lining manufacturing method for radioactive waste container
International Nuclear Information System (INIS)
Kawakami, Susumu; Sugino, Hiroyuki
1998-01-01
A recessed portion is formed on an upper surface of a filler layer made of a buffer powder filled into a container main body, the upper portion of the vessel main body is closed by a shrinkable liquid tight film. It is placed in a pressurizing container and pressed to mold a buffer lining base material integrated with the vessel main body. A flat upper surface and a containing space are formed by shaving to form a buffer lining. A disposing vessel containing radioactive wastes is inserted into the containing space, and the containing space is closed by a buffer block. The upper surface is sealed by a lid. With such a constitution, since a buffer lining integrated with the vessel main body can be formed easily inside the vessel main body, the disposing vessel can be contained in the containing vessel in a state surrounded by the buffer easily and stably without laying or piling over a large quantity of buffer blocks. (T.M.)
International Nuclear Information System (INIS)
Mun, K. H.; Seok, S. D.; Song, K. D.; Kim, I. C.
1999-01-01
A preliminary economic comparison study was performed for KALIMER(Korea Advanced LIquid MEtal Reactor)between a modular plant type with 8 150MWe modules and a 1200MWe monolithic plant type. In both cases of FOAK (First-Of-A-Kind) Plant and NOAK (Nth-Of-A-Kind) Plant, the result says that the economics of monolithic plant is superior to its modular plant. In case of NOAK plant comparison, however, the cost difference is not significant. It means that modular plant can compete with monolithic plant in capital cost if it makes efforts of cost reduction and technical progress on the assumption that the same type of NOAK plant will be constructed continuously
Characterization and testing of monolithic RERTR fuel plates
Energy Technology Data Exchange (ETDEWEB)
Keiser, D.D.; Jue, J.F.; Burkes, D.E. [Idaho National Lab., Idaho Falls, ID (United States)
2007-07-01
Monolithic fuel plates are being developed as a LEU (low enrichment uranium) fuel for application in research reactors throughout the world. These fuel plates are comprised of a U-Mo alloy foil encased in aluminum alloy cladding. Three different fabrication techniques have been looked at for producing monolithic fuel plates: hot isostatic pressing (HIP), transient liquid phase bonding (TLPB), and friction stir welding (FSW). Of these three techniques, HIP and FSW are currently being emphasized. As part of the development of these fabrication techniques, fuel plates are characterized and tested to determine properties like hardness and the bond strength at the interface between the fuel and cladding. Testing of HIP-made samples indicates that the foil/cladding interaction behavior depends on the Mo content in the UMo foil, the measured hardness values are quite different for the fuel, cladding, and interaction zone phase and Ti, Zr and Nb are the most effective diffusion barriers. For FSW samples, there is a dependence of the bond strength at the foil/cladding interface on the type of tool that is employed for performing the actual FSW process. (authors)
A system for biasing a differential amplifier
International Nuclear Information System (INIS)
Barbier, Daniel; Ittel, J.M.; Poujois, Robert
1975-01-01
This invention concerns a system for biasing a differential amplifier. It particularly applies to the integrated differential amplifiers designed with MOS field effect transistors. Variations in the technological parameters may well cause the amplifying transistors to work outside their usual operational area, in other words outside the linear part of the transfer characteristic. To ensure that these transistors function correctly, it is necessary that the value of the voltage difference at the output be equally null. To do this and to centre on the so called 'rest' point of the amplifier transfer charateristic, the condition will be set that the output potentials of each amplifier transistor should have a zero value or a constant value as sum. With this in view, the bias on the source (generally a transistor powered by its grid bias voltage) supplying current to the two amplifying transistors fitted in parallel, is permanently adjusted in a suitable manner [fr
Comparison of monolithic silica and polymethacrylate capillary columns for LC
Czech Academy of Sciences Publication Activity Database
Moravcová, D.; Jandera, P.; Urban, J.; Planeta, Josef
2004-01-01
Roč. 27, 10-11 (2004), s. 789-800 ISSN 1615-9306 R&D Projects: GA ČR(CZ) GA203/02/0023 Keywords : monolithic column s * capillary HPLC * column testing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.927, year: 2004
Buffer Sizing in 802.11 Wireless Mesh Networks
Jamshaid, Kamran; Shihada, Basem; Xia, Li; Levis, Philip
2011-01-01
We analyze the problem of buffer sizing for TCP flows in 802.11-based Wireless Mesh Networks. Our objective is to maintain high network utilization while providing low queueing delays. The problem is complicated by the time-varying capacity of the wireless channel as well as the random access mechanism of 802.11 MAC protocol. While arbitrarily large buffers can maintain high network utilization, this results in large queueing delays. Such delays may affect TCP stability characteristics, and also increase queueing delays for other flows (including real-time flows) sharing the buffer. In this paper we propose sizing link buffers collectively for a set of nodes within mutual interference range called the 'collision domain'. We aim to provide a buffer just large enough to saturate the available capacity of the bottleneck collision domain that limits the carrying capacity of the network. This neighborhood buffer is distributed over multiple nodes that constitute the network bottleneck; a transmission by any of these nodes fully utilizes the available spectral resource for the duration of the transmission. We show that sizing routing buffers collectively for this bottleneck allows us to have small buffers (as low as 2 - 3 packets) at individual nodes without any significant loss in network utilization. We propose heuristics to determine these buffer sizes in WMNs. Our results show that we can reduce the end-to-end delays by 6× to 10× at the cost of losing roughly 5% of the network capacity achievable with large buffers.
Buffer Sizing in 802.11 Wireless Mesh Networks
Jamshaid, Kamran
2011-10-01
We analyze the problem of buffer sizing for TCP flows in 802.11-based Wireless Mesh Networks. Our objective is to maintain high network utilization while providing low queueing delays. The problem is complicated by the time-varying capacity of the wireless channel as well as the random access mechanism of 802.11 MAC protocol. While arbitrarily large buffers can maintain high network utilization, this results in large queueing delays. Such delays may affect TCP stability characteristics, and also increase queueing delays for other flows (including real-time flows) sharing the buffer. In this paper we propose sizing link buffers collectively for a set of nodes within mutual interference range called the \\'collision domain\\'. We aim to provide a buffer just large enough to saturate the available capacity of the bottleneck collision domain that limits the carrying capacity of the network. This neighborhood buffer is distributed over multiple nodes that constitute the network bottleneck; a transmission by any of these nodes fully utilizes the available spectral resource for the duration of the transmission. We show that sizing routing buffers collectively for this bottleneck allows us to have small buffers (as low as 2 - 3 packets) at individual nodes without any significant loss in network utilization. We propose heuristics to determine these buffer sizes in WMNs. Our results show that we can reduce the end-to-end delays by 6× to 10× at the cost of losing roughly 5% of the network capacity achievable with large buffers.
Optical properties and light irradiance of monolithic zirconia at variable thicknesses.
Sulaiman, Taiseer A; Abdulmajeed, Aous A; Donovan, Terrence E; Ritter, André V; Vallittu, Pekka K; Närhi, Timo O; Lassila, Lippo V
2015-10-01
The aims of this study were to: (1) estimate the effect of polishing on the surface gloss of monolithic zirconia, (2) measure and compare the translucency of monolithic zirconia at variable thicknesses, and (3) determine the effect of zirconia thickness on irradiance and total irradiant energy. Four monolithic partially stabilized zirconia (PSZ) brands; Prettau® (PRT, Zirkonzahn), Bruxzir® (BRX, Glidewell), Zenostar® (ZEN, Wieland), Katana® (KAT, Noritake), and one fully stabilized zirconia (FSZ); Prettau Anterior® (PRTA, Zirkonzahn) were used to fabricate specimens (n=5/subgroup) with different thicknesses (0.5, 0.7, 1.0, 1.2, 1.5, and 2.0mm). Zirconia core material ICE® Zircon (ICE, Zirkonzahn) was used as a control. Surface gloss and translucency were evaluated using a reflection spectrophotometer. Irradiance and total irradiant energy transmitted through each specimen was quantified using MARC® Resin Calibrator. All specimens were then subjected to a standardized polishing method and the surface gloss, translucency, irradiance, and total irradiant energy measurements were repeated. Statistical analysis was performed using two-way ANOVA and post-hoc Tukey's tests (pgloss was significantly affected by polishing (p<0.05), regardless of brand and thickness. Translucency values ranged from 5.65 to 20.40 before polishing and 5.10 to 19.95 after polishing. The ranking from least to highest translucent (after polish) was: BRX=ICE=PRT
Characterization of polymer monolithic stationary phases for capillary HPLC
Czech Academy of Sciences Publication Activity Database
Moravcová, D.; Jandera, P.; Urban, J.; Planeta, Josef
2003-01-01
Roč. 26, č. 11 (2003), s. 1005-1016 ISSN 1615-9306 R&D Projects: GA ČR GA203/02/0023 Institutional research plan: CEZ:AV0Z4031919; CEZ:MSM 253100002 Keywords : monolithic column s * capillary HPLC * column testing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.108, year: 2003
Analysis of diffusive mass transport in a cracked buffer
International Nuclear Information System (INIS)
Garisto, N.C.; Garisto, F.
1989-11-01
In the disposal vault design for the Canadian Nuclear Fuel Waste Management Program, cylindrical containers of used nuclear fuel would be placed in vertical boreholes in rock and surrounded with a bentonite-based buffer material. The buffer is expected to absorb and/or retard radionuclides leaching from the fuel after the containers fail. There is some evidence, however, that the buffer may be susceptible to cracking. In this report we investigate numerically the consequences of cracking on uranium diffusion through the buffer. The derivation of the mass-transport equations and the numerical solution method are presented for the solubility-limited diffusion of uranium in a cracked buffer system for both swept-away and semi-impermeable boundary conditions at the rock-buffer interface. The results indicate that for swept-away boundary conditions the total uranium flux through the cracked buffer system is, as expected, greater than through the uncracked buffer. The effect of the cracks is strongly dependent on the ratio D/D eff , where D and D eff are the pore-water and the effective buffer diffusion coefficient, respectively. However, although a decrease in D eff enhances the effect of cracks on the total cumulative flux (relative to the uncracked buffer), it also decreases the total cumulative flux through the cracked buffer system (relative to a cracked buffer with a larger D eff value). Finally, for semi-impermeable boundary conditions, the effect of cracks on the total radionuclide flux is relatively small
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.)
Fabrication of Monolithic Bridge Structures by Vacuum-Assisted Capillary-Force Lithography
Kwak, Rhokyun; Jeong, Hoon Eui; Suh, Kahp Y.
2009-01-01
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
Solid-state disk amplifiers for fusion-laser systems
Energy Technology Data Exchange (ETDEWEB)
Martin, W.E.; Trenholme, J.B.; Linford, G.J.; Yarema, S.M.; Hurley, C.A.
1981-09-01
We review the design, performance, and operation of large-aperture (10 to 46 cm) solid-state disk amplifiers for use in laser systems. We present design data, prototype tests, simulations, and projections for conventional cylindrical pump-geometry amplifiers and rectangular pump-geometry disk amplifiers. The design of amplifiers for the Nova laser system is discussed.
International Nuclear Information System (INIS)
Floris, Patrick; Twamley, Brendan; Nesterenko, Pavel N.; Paull, Brett; Connolly, Damian
2014-01-01
Polymer monoliths in capillary (100 μm i.d.) and polypropylene pipette tip formats (vol: 20 μL) were modified with gold nano-particles (AuNP) and subsequently used for flow-through catalytic reactions. Specifically, methacrylate monoliths were modified with amine-reactive monomers using a two-step photografting method and then reacted with ethylenediamine to provide amine attachment sites for the subsequent immobilisation of 4 nm, 7 nm or 16 nm AuNP. This was achieved by flushing colloidal suspensions of gold nano-particles through each aminated polymer monolith which resulted in a multi-point covalent attachment of gold via the lone pair of electrons on the nitrogen of the free amine groups. Field emission scanning electron microscopy and scanning capacitively coupled conductivity detection was used to characterise the surface coverage of AuNP on the monoliths. The catalytic activity of AuNP immobilised on the polymer monoliths in both formats was then demonstrated using the reduction of Fe(III) to Fe(II) by sodium borohydride as a model reaction by monitoring the reduction in absorbance of the hexacyanoferrate (III) complex at 420 nm. Catalytic activity was significantly enhanced on monoliths modified with smaller AuNP with almost complete reduction (95 %) observed when using monoliths agglomerated with 7 nm AuNPs. (author)
Directory of Open Access Journals (Sweden)
Franziska Weichelt
2010-12-01
Full Text Available Porous monolithic inorganic/polymeric hybrid materials have been prepared via ring-opening metathesis copolymerization starting from a highly polar monomer, i.e., cis-5-cyclooctene-trans-1,2-diol and a 7-oxanorborn-2-ene-derived cross-linker in the presence of porogenic solvents and two types of inorganic nanoparticles (i.e., CaCO3 and calcium hydroxyapatite, respectively using the third-generation Grubbs initiator RuCl2(Py2(IMesH2(CHPh. The physico-chemical properties of the monolithic materials, such as pore size distribution and microhardness were studied with regard to the nanoparticle type and content. Moreover, the reinforced monoliths were tested for the possible use as scaffold materials in tissue engineering, by carrying out cell cultivation experiments with human adipose tissue-derived stromal cells.
BENTO buffer development program in Finland - Key issues
International Nuclear Information System (INIS)
Autio, J.; Korkiala-Tanttu, L.; Vaehaenen, M.; Koskinen, K.; Korkeakoski, P.; Haapala, K.
2010-01-01
Document available in extended abstract form only. Posiva launched a programme, BENTO, to develop technology of using bentonite in spent nuclear fuel repositories. The main purpose of the BENTO programme is to produce buffer designs and verify that they fulfil the requirements, especially safety requirements. To achieve this objective, resources and the level of expertise and know-how has to be increased. There are several uncertainties related to the functioning of the buffer components at present. An issue is defined as being significant if there is sufficient uncertainty that the buffer system might not fulfil the requirements because of the issue. These significant issues need to be resolved in order to develop a proper design and to verify the fulfilment of the requirements. The list of significant issues may change with time. Therefore it is crucial to develop adequate expertise, know-how and laboratory facilities to manage the changes. Moreover, there is confidence that by solving the open issues a defendable construction license application can be submitted in 2012. The basic nature of the programme is a combination of material and process research with the design and manufacturing of buffer components to produce feasible buffer design with proven long-term functional properties. The development work carried out under BENTO-programme has been initially divided into four different projects. During the course of work the number of projects and their content can be adjusted. The four BENTO projects are: 1. Manufacturing (MANU); 2. Design (DESI); 3. Modelling (MODE); 4. Material and Process Research (MARE). BENTO programme aims at producing feasible buffer designs which fulfil the requirements specified in Posiva's requirement management system. The designs are produced in DESI-project by following the design development scheme which starts from specification of design basis and ends in documented detailed designs and therefore DESIgn is specified as one
Liu, Chusheng; Li, Haibin; Wang, Qiqin; Crommen, Jacques; Zhou, Haibo; Jiang, Zhengjin
2017-08-04
The quest for higher column efficiency is one of the major research areas in polymer-based monolithic column fabrication. In this research, two novel polymer-based HILIC monolithic columns with 400μm I.D.×800μm O.D. were prepared based on the thermally initiated co-polymerization of N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl) ammonium betaine (SPP) and ethylene glycol dimethacrylate (EDMA) or N,N'-methylenebisacrylamide (MBA). In order to obtain a satisfactory performance in terms of column permeability, mechanical stability, efficiency and selectivity, the polymerization parameters were systematically optimized. Column efficiencies as high as 142, 000 plates/m and 120, 000 plates/m were observed for the analysis of neutral compounds at 0.6mm/s on the poly(SPP-co-MBA) and poly(SPP-co-EDMA) monoliths, respectively. Furthermore, the Van Deemter plots for thiourea on the two monoliths were compared with that on a commercial silica based ZIC-HILIC column (3.5μm, 200Å, 150mm×300μm I.D.) using ACN/H 2 O (90/10, v/v) as the mobile phase at room temperature. It was noticeable that the Van Deemter curves for both monoliths, particularly the poly(SPP-co-MBA) monolith, are significantly flatter than that obtained for the ZIC-HILIC column, which indicates that in spite of their larger internal diameters, they yield better overall efficiency, with less peak dispersion, across a much wider range of usable linear velocities. A clearly better separation performance was also observed for nucleobases, nucleosides, nucleotides and small peptides on the poly(SPP-co-MBA) monolith compared to the ZIC-HILIC column. It is particularly worth mentioning that these 400μm I.D. polymer-based HILIC monolithic columns exhibit enhanced mechanical strength owing to the thicker capillary wall of the fused-silica capillaries. Copyright © 2017 Elsevier B.V. All rights reserved.
Zhong, Jing; Bai, Ligai; Qin, Junxiao; Wang, Jiafei; Hao, Mengbei; Yang, Gengliang
2015-04-01
A novel organic monolithic stationary phase was prepared for high-performance liquid chromatography (HPLC) by in situ copolymerization. In which, triallyl isocyanurate (TAIC) and trimethylolpropane triacrylate (TMPTA) in a binary porogenic solvent consisting of polyethylene glycol 200 and 1, 2-propanediol were used. The resultant monoliths with different column properties (e.g., morphology and pressure) were optimized by adjusting the ratio of TMPTA/TAIC and the composition of porogenic solvent. The resulting poly(TAIC-co-TMPTA) monolith showed a relatively homogeneous structure, good permeability and mechanical stability. The chemical group of the monolith was assayed by the infrared spectra method, the morphology of monolithic material was studied by scanning electron microscopy and the pore size distribution was determined by a mercury porosimeter. A series of small molecules were used to evaluate the column performance in terms of hydrophobic mode. At an optimized flow rate of 1.0 mL min(-1), the theoretical plate number of analyte was >15,000 plates m(-1). These applications demonstrated that the monoliths could be successfully used as the stationary phase in conjunction with HPLC to separate small molecules from the mixture. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Energy Technology Data Exchange (ETDEWEB)
Neretnieks, Ivars [Dept. of Chemical Engineering and Technology, Royal Institute of Technology, Stockholm (Sweden)
2006-12-15
The compacted bentonite buffer that surrounds the canister with spent fuel is designed not to allow water to flow through it in any appreciable quantities. Should the buffer be severely damaged water could flow to the canister and bring with it corrosive agent such as sulphide. This could speed up the rate of copper corrosion. Should the canister have a damage or be corroded so that the spent fuel inside the canister comes in contact with the water radionuclides could dissolve in the water and be carried away. Two modes of canister damage and their consequences for solute transport are explored in this report. In one case the buffer can potentially be eroded by the water seeping in the fractures in the surrounding rock and attain a high hydraulic conductivity allowing water to flow through it, at least locally. In another case it is conjectured that the buffer is cemented and becomes brittle. Then a crack could conceivably form in the cemented buffer allowing water to flow through it directly to the canister surface. Both cases are hypothetical although in the erosion case the erosion rate could possibly be quantified. The cases studied are to be seen as exploratory calculations for 'what if' cases. Some worst case assumptions have been used to explore bounding scenarios. Thus for the erosion case it is assumed that the hydraulic conductivity is so high that the buffer exerts negligible resistance to water flow. This implies that all the water that can flow through the fractures intersecting the deposition hole can reach the canister. Similarly for the cemented buffer case it is assumed that the crack in the buffer directly connects the rock fracture to the canister surface. For these circumstances it is found that the flowrate that can enter the deposition hole will be approximately two times as large as the water flow that would pass a projected area equal to that of the deposition hole. Thus if the flux in the rock some distance from the deposition
International Nuclear Information System (INIS)
Neretnieks, Ivars
2006-12-01
The compacted bentonite buffer that surrounds the canister with spent fuel is designed not to allow water to flow through it in any appreciable quantities. Should the buffer be severely damaged water could flow to the canister and bring with it corrosive agent such as sulphide. This could speed up the rate of copper corrosion. Should the canister have a damage or be corroded so that the spent fuel inside the canister comes in contact with the water radionuclides could dissolve in the water and be carried away. Two modes of canister damage and their consequences for solute transport are explored in this report. In one case the buffer can potentially be eroded by the water seeping in the fractures in the surrounding rock and attain a high hydraulic conductivity allowing water to flow through it, at least locally. In another case it is conjectured that the buffer is cemented and becomes brittle. Then a crack could conceivably form in the cemented buffer allowing water to flow through it directly to the canister surface. Both cases are hypothetical although in the erosion case the erosion rate could possibly be quantified. The cases studied are to be seen as exploratory calculations for 'what if' cases. Some worst case assumptions have been used to explore bounding scenarios. Thus for the erosion case it is assumed that the hydraulic conductivity is so high that the buffer exerts negligible resistance to water flow. This implies that all the water that can flow through the fractures intersecting the deposition hole can reach the canister. Similarly for the cemented buffer case it is assumed that the crack in the buffer directly connects the rock fracture to the canister surface. For these circumstances it is found that the flowrate that can enter the deposition hole will be approximately two times as large as the water flow that would pass a projected area equal to that of the deposition hole. Thus if the flux in the rock some distance from the deposition hole is 1
Liquid growth hormone: preservatives and buffers
DEFF Research Database (Denmark)
Kappelgaard, Anne-Marie; Anders, Bojesen; Skydsgaard, Karen
2004-01-01
injection are dependent on the preservative used in the formulation and the concentration of GH. Injection pain may also be related to the buffer substance and injection volume. A liquid formulation of GH, Norditropi SimpleXx, has been developed that dispenses with the need for reconstitution before...... solution. More pain was also reported following large volume injections and following injections with solutions containing high protein concentrations. In summary, optimization of the preservative and buffer content of a liquid GH formulation may reduce injection pain and lead to improved patient...... administration. The formulation uses phenol (3 mg/ml) as a preservative (to protect product from microbial degradation or contamination) and histidine as a buffer. Alternative preservatives used in other GH formulations include m-cresol (9 mg/ml) and benzyl alcohol (3-9 mg/ml). Buffering agents include citrate...
Multi-pass amplifier architecture for high power laser systems
Manes, Kenneth R; Spaeth, Mary L; Erlandson, Alvin C
2014-04-01
A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.
Wang, Jiafei; Bai, Ligai; Wei, Zhen; Qin, Junxiao; Ma, Yamin; Liu, Haiyan
2015-06-01
An ionic liquid was incorporated into the porous polymer monoliths to afford stationary phases with enhanced chromatographic performance for small molecules in reversed-phase high-performance liquid chromatography. The effect of the ionic liquid in the polymerization mixture on the performance of the monoliths was studied in detail. While monoliths without ionic liquid exhibited poor resolution and low efficiency, the addition of ionic liquid to the polymerization mixture provides highly increased resolution and high efficiency. The chromatographic performances of the monoliths were demonstrated by the separations of various small molecules including aromatic hydrocarbons, isomers, and homologues using a binary polar mobile phase. The present column efficiency reached 27 000 plates/m, which showed that the ionic liquid monoliths are alternative stationary phases in the separation of small molecules by high-performance liquid chromatography. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Design of an 1800nm Raman amplifier
DEFF Research Database (Denmark)
Svane, Ask Sebastian; Rottwitt, Karsten
2013-01-01
We present the experimental results for a Raman amplifier that operates at 1810 nm and is pumped by a Raman fiber laser at 1680 nm. Both the pump laser and the Raman amplifier is polarization maintaining. A challenge when scaling Raman amplifiers to longer wavelengths is the increase...... in transmission loss, but also the reduction in the Raman gain coefficient as the amplifier wavelength is increased. Both polarization components of the Raman gain is characterized, initially for linearly co-polarized signal and pump, subsequently linearly polarized orthogonal signal and pump. The noise...
Transferrable monolithic III-nitride photonic circuit for multifunctional optoelectronics
Shi, Zheng; Gao, Xumin; Yuan, Jialei; Zhang, Shuai; Jiang, Yan; Zhang, Fenghua; Jiang, Yuan; Zhu, Hongbo; Wang, Yongjin
2017-12-01
A monolithic III-nitride photonic circuit with integrated functionalities was implemented by integrating multiple components with different functions into a single chip. In particular, the III-nitride-on-silicon platform is used as it integrates a transmitter, a waveguide, and a receiver into a suspended III-nitride membrane via a wafer-level procedure. Here, a 0.8-mm-diameter suspended device architecture is directly transferred from silicon to a foreign substrate by mechanically breaking the support beams. The transferred InGaN/GaN multiple-quantum-well diode (MQW-diode) exhibits a turn-on voltage of 2.8 V with a dominant electroluminescence peak at 453 nm. The transmitter and receiver share an identical InGaN/GaN MQW structure, and the integrated photonic circuit inherently works for on-chip power monitoring and in-plane visible light communication. The wire-bonded monolithic photonic circuit on glass experimentally demonstrates in-plane data transmission at 120 Mb/s, paving the way for diverse applications in intelligent displays, in-plane light communication, flexible optical sensors, and wearable III-nitride optoelectronics.
CMOS monolithic active pixel sensors for high energy physics
Energy Technology Data Exchange (ETDEWEB)
Snoeys, W., E-mail: walter.snoeys@cern.ch
2014-11-21
Monolithic pixel detectors integrating sensor matrix and readout in one piece of silicon are only now starting to make their way into high energy physics. Two major requirements are radiation tolerance and low power consumption. For the most extreme radiation levels, signal charge has to be collected by drift from a depletion layer onto a designated collection electrode without losing the signal charge elsewhere in the in-pixel circuit. Low power consumption requires an optimization of Q/C, the ratio of the collected signal charge over the input capacitance [1]. Some solutions to combine sufficient Q/C and collection by drift require exotic fabrication steps. More conventional solutions up to now require a simple in-pixel readout circuit. Both high voltage CMOS technologies and Monolithic Active Pixel Sensors (MAPS) technologies with high resistivity epitaxial layers offer high voltage diodes. The choice between the two is not fundamental but more a question of how much depletion can be reached and also of availability and cost. This paper tries to give an overview.
Immobilization of trypsin on sub-micron skeletal polymer monolith
Energy Technology Data Exchange (ETDEWEB)
Yao Chunhe [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Qi Li, E-mail: qili@iccas.ac.cn [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Hu Wenbin [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Wang Fuyi [Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Yang Gengliang [College of Pharmacy, Hebei University, Baoding 071002 (China)
2011-04-29
A new kind of immobilized trypsin reactor based on sub-micron skeletal polymer monolith has been developed. Covalent immobilization of trypsin on this support was performed using the epoxide functional groups in either a one- or a multi-step reaction. The proteolytic activity of the immobilized trypsin was measured by monitoring the formation of N-{alpha}-benzoyl-L-arginine (BA) which is the digestion product of a substrate N-{alpha}-benzoyl-L-arginine ethyl ester (BAEE). Results showed that the digestion speed was about 300 times faster than that performed in free solution. The performance of such an enzyme reactor was further demonstrated by digesting protein myoglobin. It has been found that the protein digestion could be achieved in 88 s at 30 deg. C, which is comparable to 24 h digestion in solution at 37 {sup o}C. Furthermore, the immobilized trypsin exhibits increased stability even after continuous use compared to that in free solution. The present monolithic enzyme-reactor provides a promising platform for the proteomic research.
International Nuclear Information System (INIS)
Cardona, Ana I.; Candal, Roberto; Sanchez, Benigno; Avila, Pedro; Rebollar, Moises
2004-01-01
In this article, the comparative results of the photocatalytic oxidation of trichloroethylene (TCE) alone and a mixture of chlorinated hydrocarbons (trichloroethylene, perchloroethylene and chloroform) in gas phase, obtained with three different monolithic catalysts in a flat reactor frontally illuminated with a Xenon lamp are presented. The three catalysts incorporate titanium dioxide (TiO 2 ) as active phase on a magnesium silicate support, by means of different procedures: (i) incorporation of commercial TiO 2 powder into the silicate matrix ('massic monolith'); (ii) sol-gel coating of the silicate support; (iii) impregnation with a commercial TiO 2 aqueous suspension of the same silicate support. In the first case, the massic monolith was made from a 50:50 w/w mixture of magnesium silicate and 'Titafrance G5' TiO 2 powder. In the second case, a magnesium silicate monolith was coated with several layers of an aqueous TiO 2 sol prepared from hydrolysis and condensation of titanium tetra-isopropoxide (Ti(OC 3 H 7 ) 4 ) in excess of acidified water (acid catalysis). The third catalyst was prepared by impregnating the same silicate support with several layers of 'Titafrance G5' TiO 2 powder water suspension. All the catalysts were thermal treated under comparable conditions in order to fix the TiO 2 active phase to the silicate support. Although the performance of the massic monolith was better than the sol-gel monolith, the latter is of great interest because this technique allows the chemical composition of the active films to be easily modified
Capillary trap column with strong cation-exchange monolith for automated shotgun proteome analysis.
Wang, Fangjun; Dong, Jing; Jiang, Xiaogang; Ye, Mingliang; Zou, Hanfa
2007-09-01
A 150 microm internal diameter capillary monolithic column with a strong cation-exchange stationary phase was prepared by direct in situ polymerization of ethylene glycol methacrylate phosphate and bisacrylamide in a trinary porogenic solvent consisting dimethylsulfoxide, dodecanol, and N,N'-dimethylformamide. This phosphate monolithic column exhibits higher dynamic binding capacity, faster kinetic adsorption of peptides, and more than 10 times higher permeability than the column packed with commercially available strong cation-exchange particles. It was applied as a trap column in a nanoflow liquid chromatography-tandem mass spectrometry system for automated sample injection and online multidimensional separation. It was observed that the sample could be loaded at a flow rate as high as 40 microL/min with a back pressure of approximately 1300 psi and without compromising the separation efficiency. Because of its good orthogonality to the reversed phase separation mechanism, the phosphate monolithic trap column was coupled with a reversed-phase column for online multidimensional separation of 19 microg of the tryptic digest of yeast proteins. A total of 1522 distinct proteins were identified from 5608 unique peptides (total of 54,780 peptides) at the false positive rate only 0.46%.
Multiple excitation regenerative amplifier inertial confinement system
International Nuclear Information System (INIS)
George, V.E.; Haas, R.A.; Krupke, W.F.; Schlitt, L.G.
1980-01-01
The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation
DEFF Research Database (Denmark)
Borri, P.; Langbein, W.; Hvam, Jørn Märcher
2001-01-01
The ultrafast gain dynamics in an electrically pumped InAs/InGaAs/GaAs quantum-dot amplifier are measured at room temperature with femtosecond resolution, and compared with results on an InGaAsP bulk amplifier. The role of spectral hole burning and carrier heating in the recovery of the gain...
DEFF Research Database (Denmark)
Sitchinava, Nodar; Zeh, Norbert
2012-01-01
We present the parallel buffer tree, a parallel external memory (PEM) data structure for batched search problems. This data structure is a non-trivial extension of Arge's sequential buffer tree to a private-cache multiprocessor environment and reduces the number of I/O operations by the number of...... in the optimal OhOf(psortN + K/PB) parallel I/O complexity, where K is the size of the output reported in the process and psortN is the parallel I/O complexity of sorting N elements using P processors....
Fortier, Julien; Truax, Benoit; Gagnon, Daniel; Lambert, France
2015-05-01
In many temperate agricultural areas, riparian forests have been converted to cultivated land, and only narrow strips of herbaceous vegetation now buffer many farm streams. The afforestation of these riparian zones has the potential to increase carbon (C) storage in agricultural landscapes by creating a new biomass sink for atmospheric CO2. Occurring at the same time, the storage of nitrogen (N) and phosphorus (P) in plant biomass, is an important water quality function that may greatly vary with types of riparian vegetation. The objectives of this study were (1) to compare C, N and P storage in aboveground, belowground and detrital biomass for three types of riparian vegetation cover (9-year-old hybrid poplar buffers, herbaceous buffers and natural woodlots) across four agricultural sites and (2) to determine potential vegetation cover effects on soil nutrient supply rate in the riparian zone. Site level comparisons suggest that 9-year-old poplar buffers have stored 9-31 times more biomass C, 4-10 times more biomass N, and 3-7 times more biomass P than adjacent non managed herbaceous buffers, with the largest differences observed on the more fertile sites. The conversion of these herbaceous buffers to poplar buffers could respectively increase C, N and P storage in biomass by 3.2-11.9 t/ha/yr, 32-124 kg/ha/yr and 3.2-15.6 kg/ha/yr, over 9 years. Soil NO3 and P supply rates during the summer were respectively 57% and 66% lower in poplar buffers than in adjacent herbaceous buffers, potentially reflecting differences in nutrient storage and cycling between the two buffer types. Biomass C ranged 49-160 t/ha in woodlots, 33-110 t/ha in poplar buffers and 3-4 t/ha in herbaceous buffers. Similar biomass C stocks were found in the most productive poplar buffer and three of the four woodlots studied. Given their large and varied biomass C stocks, conservation of older riparian woodlots is equally important for C balance management in farmland. In addition, the
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.
The OPTHER Project: Progress toward the THz Amplifier
DEFF Research Database (Denmark)
Paoloni, C; Brunetti, F; Di Carlo, A
2011-01-01
This paper describes the status of the OPTHER (OPtically driven TeraHertz AmplifiERs) project and progress toward the THz amplifier realization. This project represents a considerable advancement in the field of high frequency amplification. The design and realization of a THz amplifier within...... this project is a consolidation of efforts at the international level from the leading scientific and industrial European organizations working with vacuum electronics....
Moisture Buffer Value of Building Materials
DEFF Research Database (Denmark)
Rode, Carsten; Peuhkuri, Ruut; Time, Berit
2007-01-01
When building materials are in contact with indoor air they have some effect to moderate the variations of indoor humidity in occupied buildings. But so far there has been a lack of a standardized quantity to characterize the moisture buffering capability of materials. It has been the objective o...... is a test protocol which expresses how materials should be tested for determination of their Moisture Buffer Value. Finally, the paper presents some of the results of a Round Robin Test on various typical building materials that has been carried out in the project....... of a recent Nordic project to define such a quantity, and to declare it in the form of a NORDTEST method. The Moisture Buffer Value is the figure that has been developed in the project as a way to appraise the moisture buffer effect of materials, and the value is described in the paper. Also explained...
Directory of Open Access Journals (Sweden)
N. Kurose
2014-12-01
Full Text Available We have grown conductive aluminum nitride (AlN layers using the spontaneous via holes formation technique on an n+-Si substrate for vertical-type device fabrication. The size and density of the via holes are controlled through the crystal growth conditions used for the layer, and this enables the conductance of the layer to be controlled. Using this technique, we demonstrate the fabrication of a vertical-type deep ultraviolet (DUV photo-sensor. This technique opens up the possibility of fabrication of monolithically integrated on-chip DUV sensors and DUV light-emitting devices (LEDs, including amplifiers, controllers and other necessary functional circuits, on a Si substrate.
Ito, Kazuaki; Takayama, Yohichi; Makabe, Nobuyuki; Mitsui, Ryo; Hirokawa, Takeshi
2005-08-12
A fast and highly sensitive ion chromatographic method using monolithic ODS columns was developed for the determination of nitrite (NO2-) and nitrate (NO3-) in seawater. Two monolithic ODS columns (50 mm x 4.6 mm i.d. + 100 mm x 4.6 mm i.d.) connected in series were coated and equilibrated with 5 mM cetyltrimethylammonium chloride (CTAC) aqueous solution. The column efficiency with 0.5 M NaCl as the mobile phase did not decrease in spite of the increase in flow rate of the mobile phase. Thus, good chromatograms were obtained within 3 minutes for NO2- and NO3 in artificial seawater without interferences by coexisting ions. The detection limit (S/N = 3) with UV detection at 225 nm was 0.8 and 1.6 microg/L for NO2- and NO3-, respectively. The characteristics of the monolithic CTA(+)-coated ODS columns were discussed. The present method was successfully applied to the fast and sensitive determination of NO2- and NO3- in real seawater samples.
Affinity monolith chromatography: A review of general principles and applications.
Li, Zhao; Rodriguez, Elliott; Azaria, Shiden; Pekarek, Allegra; Hage, David S
2017-11-01
Affinity monolith chromatography, or AMC, is a liquid chromatographic method in which the support is a monolith and the stationary phase is a biological-binding agent or related mimic. AMC has become popular for the isolation of biochemicals, for the measurement of various analytes, and for studying biological interactions. This review will examine the principles and applications of AMC. The materials that have been used to prepare AMC columns will be discussed, which have included various organic polymers, silica, agarose, and cryogels. Immobilization schemes that have been used in AMC will also be considered. Various binding agents and applications that have been reported for AMC will then be described. These applications will include the use of AMC for bioaffinity chromatography, immunoaffinity chromatography, dye-ligand affinity chromatography, and immobilized metal-ion affinity chromatography. The use of AMC with chiral stationary phases and as a tool to characterize biological interactions will also be examined. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Monolithic Magneto-Optical Nanocomposites of Barium Hexaferrite Platelets in PMMA.
Ferk, Gregor; Krajnc, Peter; Hamler, Anton; Mertelj, Alenka; Cebollada, Federico; Drofenik, Miha; Lisjak, Darja
2015-06-12
The incorporation of magnetic barium hexaferrite nanoparticles in a transparent polymer matrix of poly(methyl methacrylate) (PMMA) is reported for the first time. The barium hexaferrite nanoplatelets doped with Sc(3+), i.e., BaSc0.5Fe11.5O12 (BaHF), having diameters in the range 20 to 130 nm and thicknesses of approximately 5 nm, are synthesized hydrothermally and stabilized in 1-butanol with dodecylbenzenesulfonic acid. This method enables the preparation of monolithic nanocomposites by admixing the BaHF suspension into a liquid monomer, followed by in-situ, bulk free-radical polymerization. The PMMA retains its transparency for loadings of BaHF nanoparticles up to 0.27 wt.%, meaning that magnetically and optically anisotropic, monolithic nanocomposites can be synthesized when the polymerization is carried out in a magnetic field. The excellent dispersion of the magnetic nanoparticles, coupled with a reasonable control over the magnetic properties achieved in this investigation, is encouraging for the magneto-optical applications of these materials.
LePix-A high resistivity, fully depleted monolithic pixel detector
Giubilato, P; Mugnier, H; Bisello, D; Marchioro, A; Snoeys, W; Denes, P; Pantano, D; Rousset, J; Mattiazzo, S; Kloukinas, K; Potenza, A; Rivetti, A; Chalmet, P
2013-01-01
The LePix project explores monolithic pixel sensors fabricated in a 90 nm CMOS technology built over a lightly doped substrate. This approach keeps the advantages usually offered by Monolithic Active Pixel Sensors (MAPS), like a low input capacitance, having a single piece detector and using a standard CMOS production line, and adds the benefit of charge collection by drift from a depleted region several tens of microns deep into the substrate, therefore providing an excellent signal to noise ratio and a radiation tolerance superior to conventional un-depleted MAPS. Such sensors are expected to offer significant cost savings and reduction of power consumption for the same performance, leading to the use of much less material in the detector (less cooling and less copper), addressing one of the main limitations of present day particle tracking systems. The latest evolution of the project uses detectors thinned down to 50 mu m to obtain back illuminated sensors operated in full depletion mode. By back processin...
Cheap C18-modified silica monolith particles as HPLC stationary phase of good separation efficiency
Energy Technology Data Exchange (ETDEWEB)
Ali, Ashraf; Ali, Faiz; Cheong, Woo Jo [Dept. of of Chemistry, Inha University, Incheon (Korea, Republic of)
2015-06-15
The columns packed with particles have a high efficiency but they are accompanied with a high column back pressure due to lower permeability, while the monolithic columns have a high permeability but they result in inferior separation efficiency for the analysis of small molecules in HPLC. In our laboratory,we have been using the pseudo-monolithic silica particles with C-18 ligand or polystyrene film. The column to column reproducibility was evaluated based on three columns made of three different batches of silica monolith particles, and better than 4.5% in N, and 1.6% in retention time were observed. The day to day reproducibility of a single column for three consecutive days was found better than 1.5% both in N and retention time. The van Deemter plots were derived for awide range of flow rates. The trends of van Deemter plots were similar to those of common patterns and the optimal flow rate was found to be 25 μL/min.
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.
Electroactive monolithic μchip for electrochemically-responsive chromatography
Power, Aoife
2013-01-01
The EMμ project’s focus is ultimately, the development of an electroactive monolith that can be incorporated into a microfluidic system for electroanalytical applications such as sensing and electrochemically-controlled extractions and separations. To date our have made several significant advances to achieving this end goal. Firstly a facile fabrication method which allows for the production of fully disposable, gasket–free thin–layer cells suitable for EMμ was developed. A polydimethylsilox...