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Review of Scientific Instruments

Christopher B Saltonstall, Thomas E Beechem, Jatin Amatya, Jerrold Floro, Pamela M Norris, Patrick E Hopkins
Spectral linewidths are used to assess a variety of physical properties, even as spectral overlap makes quantitative extraction difficult owing to uncertainty. Uncertainty, in turn, can be minimized with the choice of appropriate experimental conditions used in spectral collection. In response, we assess the experimental factors dictating uncertainty in the quantification of linewidth from a Raman experiment highlighting the comparative influence of (1) spectral resolution, (2) signal to noise, and (3) relative peak intensity (RPI) of the overlapping peaks...
January 2019: Review of Scientific Instruments
Hans Moosmüller, W Patrick Arnott
No abstract text is available yet for this article.
January 2019: Review of Scientific Instruments
Duane J McCrory, Mark A Anders, Jason T Ryan, Pragya R Shrestha, Kin P Cheung, Patrick M Lenahan, Jason P Campbell
We report on a novel electron paramagnetic resonance (EPR) technique that merges electrically detected magnetic resonance (EDMR) with a conventional semiconductor wafer probing station. This union, which we refer to as wafer-level EDMR (WL-EDMR), allows EDMR measurements to be performed on an unaltered, fully processed semiconductor wafer. Our measurements replace the conventional EPR microwave cavity or resonator with a very small non-resonant near-field microwave probe. Bipolar amplification effect, spin dependent charge pumping, and spatially resolved EDMR are demonstrated on various planar 4H-silicon carbide metal-oxide-semiconductor field-effect transistor (4H-SiC MOSFET) structures...
January 2019: Review of Scientific Instruments
Yin Song, Arkaprabha Konar, Riley Sechrist, Ved Prakash Roy, Rong Duan, Jared Dziurgot, Veronica Policht, Yassel Acosta Matutes, Kevin J Kubarych, Jennifer P Ogilvie
Multidimensional spectroscopy is the optical analog to nuclear magnetic resonance, probing dynamical processes with ultrafast time resolution. At optical frequencies, the technical challenges of multidimensional spectroscopy have hindered its progress until recently, where advances in laser sources and pulse-shaping have removed many obstacles to its implementation. Multidimensional spectroscopy in the visible and infrared (IR) regimes has already enabled respective advances in our understanding of photosynthesis and the structural rearrangements of liquid water...
January 2019: Review of Scientific Instruments
Hao Zeng, Jian Gao, Peng Ye, Lianping Guo, Ke Liao
Electromagnetic interference (EMI) measurement is essential in wireless communications to avoid both performance degradation and serious fault failures. In this paper, we present the design of an acquisition system for a time-domain EMI measurement receiver intended for monitoring potential EMI. The platform consists of both hardware and software systems. The hardware system is constructed using a modular design method and contains a conditioning module, a data acquisition and processing module, and a clock generation module...
January 2019: Review of Scientific Instruments
N Barbero, G Abbiati, E Enrico, G Amato, E Vittone, H-R Ott, J Mesot, T Shiroka
The investigation of materials under extreme pressure conditions requires high-performance cells whose design invariably involves trade-offs between the maximum achievable pressure, the allowed sample volume, and the possibility of real-time pressure monitoring. With a newly conceived hybrid piston-clamped anvil cell, we offer a relatively simple and versatile system, suitable for nuclear magnetic resonance experiments up to 4.4 GPa. Finite-element models, taking into account mechanical and thermal conditions, were used to optimize and validate the design prior to the realization of the device...
January 2019: Review of Scientific Instruments
D J Lee, W Lee, H K Park, T G Kim
A large-aperture beam splitter has been developed for simultaneous operation of two millimeter-wave diagnostics employing different probe beams in the frequency and polarization, microwave imaging reflectometer (∼85 GHz X-mode), and collective scattering system (300 GHz O-mode), on the Korea Superconducting Tokamak Advanced Research device. The beam splitter was designed based on a polarizer concept (i.e., grid of metal strips on a thin dielectric sheet), and this can be an optimal solution for these two diagnostics...
January 2019: Review of Scientific Instruments
S P Giblin, G Lorusso
We compared the performance of a commercial ammeter and a home-made integrating electrometer in reading ionisation chamber currents less than 100 pA. The integrating electrometer charges a capacitor with the unknown current and measures the resulting rate of change of voltage, whereas the ammeter uses a high-value resistor as the feedback element to an amplifier which converts current to voltage. The noise performance of both systems was very similar for averaging times less than 1000 s. Both systems were calibrated using a reference current source with 1 part per million (ppm) accuracy, revealing an error of 460 ppm in the electrometer indicated current, of unknown origin...
January 2019: Review of Scientific Instruments
A Serrano-Muñoz, S Frayle-Pérez, A Reyes, Y Almeida, E Altshuler, G Viera-López
The precise and continuous tracking of millimetric-sized walkers-such as ants-is quite important in behavioral studies. However, due to technical limitations, most studies concentrate on trajectories within areas no more than 100 times bigger than the size of the walker or longer trajectories at the expense of either accuracy or continuity. Our work describes a scientific instrument designed to push the boundaries of precise and continuous motion analysis up to 1000 body lengths or more. It consists of a mobile robotic platform that uses digital image processing techniques to track the targets in real time by calculating their spatial position...
January 2019: Review of Scientific Instruments
Xin Xu, Wei-Heng Shih, Wan Y Shih
Mammography is the only Food and Drug Administration approved breast cancer screening method. The drawback of the tumor image in a mammogram is the lack of tumor depth information as it is only a 2-dimensional projection of a 3-dimensional (3D) tumor. In this work, we investigated 3D tumor imaging by assessing tumor depth information using a set of piezoelectric fingers (PEFs) with different probe sizes which were known to be capable of eliciting tissue elastic responses to different depths and tested it on model tumor tissues consisted of gelatin with suspended clay inclusions...
January 2019: Review of Scientific Instruments
M J Rosenberg, D B Thorn, N Izumi, D Williams, M Rowland, G Torres, M Haugh, P Hillyard, N Adelman, T Schuler, M A Barrios, J P Holder, M B Schneider, K B Fournier, D K Bradley, S P Regan
The sensitivity of Fuji SR and MS image plates (IPs) used in x-ray spectrometers on OMEGA and the National Ignition Facility has been measured using two techniques. A set of radioisotopes has been used to constrain image-plate sensitivity between 6 and 60 keV, while a Manson source has been used to expose image plates to x rays at energies between 1.5 and 8 keV. These data have shown variation in sensitivity on the order of 5% for a given IP type and scanner settings. The radioisotope technique has also been used to assess IP fading properties for MS-type plates over long times...
January 2019: Review of Scientific Instruments
Libo Zhao, Yunyun Luo, Xiangxiang Huang, Xiangyang Zhou, Rahman -Hebibul, Jianjun Ding, Zhikang Li, Zhuangde Jiang
A novel microsensor has been designed for the measurement of thermal conductivity of fluids based on the three omega (3ω) method. First, we theoretically analyzed the heat conduction using the 3ω method to demonstrate the mechanism of the microsensor to measure the thermal conductivity of a fluid. For the main structure of the microsensor, a heater was supported by the thin dielectric layers. In order to obtain the optimal parameters, we used the finite element method to simulate the working condition of the microsensor...
January 2019: Review of Scientific Instruments
Marco Grisi, Gaurasundar Marc Conley, Pascal Sommer, Jacques Tinembart, Giovanni Boero
We present the design and performance of a broad-band single-chip integrated transceiver specifically conceived for nuclear magnetic resonance magnetometry. The single-chip transceiver is realized using a standard silicon complementary metal-oxide-semiconductor integrated circuit technology. A radio-frequency (RF) transmit amplifier, a transmit/receive switch, a low noise RF receive amplifier, a quadrature (IQ)-mixer, and two intermediate frequency amplifiers are integrated on a single silicon chip of 1.8 mm2 ...
January 2019: Review of Scientific Instruments
Anitha V P, Priyavandana J Rathod, Jayesh Raval, Renu Bahl, Y C Saxena
A washer-gun based plasma system has been developed to enable high power microwave (HPM)-plasma interaction in a system for microwave plasma experiments. The critical pre-requisites of the plasma are density, ne ∼ (1-10) × 1017 m-3 , uniformity over a radial extent ≈10 cm and axial extent ≈20-30 cm, an axial density gradient of scale-length Ln ≈ wavelength of HPM, and ambient pressure low enough to maintain electron-neutral collision frequency much less than plasma frequency. The system developed deploys a ten stage pulse forming network, discharged to the washer-gun to produce pulsed (τpulse ∼ 100 μs) discharges that get ejected into an experimental chamber...
January 2019: Review of Scientific Instruments
Xiang Wang, Chengda Dai, Qingsong Wang, Long Hao, Jinsong Bai, Yuying Yu, Qiang Wu, Hua Tan, Jianbo Hu, Guoqiang Luo, Qiang Shen, Lianmeng Zhang
A three-stage gas gun, composed of a two-stage gas gun and the add-on part, has been developed to launch high-Z (tantalum, for example) flyer plates up to 10 km/s for ultrahigh-pressure Hugoniot measurements. Great care has been taken to optimize the add-on part in which a specially designed graded density impactor is employed to quasi-isentropically accelerate the high-Z flyer plate for maximizing its impact velocity. The shock wave in the target generated by the flyer plate is characterized with the flatness of the shock-front better than 1 ns in the concerned area and the uncertainty of the shock-wave velocity less than 2%, thus satisfying the requirements for high-precision Hugoniot measurements...
January 2019: Review of Scientific Instruments
S P Theocharous, S N Bland, D Yanuka, A Rososhek, M P Olbinado, A Rack, Ya E Krasik
We describe the first use of synchrotron radiation to probe pulsed power driven high energy density physics experiments. Multi-frame x-ray radiography with interframe spacing of 704 ns and temporal resolution of <100 ps was used to diagnose the electrical explosion of different wire configurations in water including single copper and tungsten wires, parallel copper wire pairs, and copper x-pinches. Such experiments are of great interest to a variety of areas including equation of state studies and high pressure materials research, but the optical diagnostics that are usually employed in these experiments are unable to probe the areas behind the shock wave generated in the water, as well as the internal structure of the exploding material...
January 2019: Review of Scientific Instruments
Oleksandr Romanenko, Vladimir Havranek, Anna Mackova, Marie Davidkova, Mariapompea Cutroneo, Alexander G Ponomarev, Gyula Nagy, James Stammers
The Tandetron Laboratory of the Nuclear Physics Institute of the Czech Academy of Sciences is equipped with five beam lines associated with a 3 MV tandem electrostatic accelerator model 4130 MC from High Voltage Engineering Europa B.V. This accelerator is coupled with two duoplasmatron sources and a single sputter ion source and provides ions from hydrogen to gold. One of these lines is a nuclear microbeam facility, utilizing ion beams of micro- and sub-micro sizes for materials research by use of particle induced x-ray emission spectroscopy, particle induced gamma emission, Rutherford back-scattering spectroscopy, and scanning transmission ion microscopy methods as well as for ion beam writing...
January 2019: Review of Scientific Instruments
R Kube, F M Bianchi, D Brunner, B LaBombard
Understanding the statistics of fluctuation driven flows in the boundary layer of magnetically confined plasmas is desired to accurately model the lifetime of the vacuum vessel components. Mirror Langmuir probes (MLPs) are a novel diagnostic that uniquely allow us to sample the plasma parameters on a time scale shorter than the characteristic time scale of their fluctuations. Sudden large-amplitude fluctuations in the plasma degrade the precision and accuracy of the plasma parameters reported by MLPs for cases in which the probe bias range is of insufficient amplitude...
January 2019: Review of Scientific Instruments
Philipp Bohr, Heiko Stettin, Jörg Läuger
Rheometric investigations using cone-plate geometries are one of the most basic flow situations. This publication presents our findings on the analytic solution for the velocity field in the gap between two conical boundaries for rheometric flows, which has been designed by us and is referred to as "cone-pan." The formulae are derived from the Navier-Stokes-equation in a suitable coordinate system and found in accordance with previous findings. We experimentally verify the formulae for Newtonian fluids and investigate in brief the limits of stability of this flow experimentally and from a literature discussion...
January 2019: Review of Scientific Instruments
Theo Cremers, Niek Janssen, Edwin Sweers, Sebastiaan Y T van de Meerakker
Zeeman deceleration is a relatively new technique used to obtain full control over the velocity of paramagnetic atoms or molecules in a molecular beam. We present a detailed description of a multistage Zeeman decelerator that has recently become operational in our laboratory [Cremers et al., Phys. Rev. A 98, 033406 (2018)] and that is specifically optimized for crossed molecular beams scattering experiments. The decelerator consists of an alternating array of 100 solenoids and 100 permanent hexapoles to guide or decelerate beams of paramagnetic atoms or molecules...
January 2019: Review of Scientific Instruments
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