Low temperature system for a large volume multi-anvil press
A new custom-designed system for a 3000 ton multi-anvil press has been developed to reachtemperatures below roomtemperature athigh pressures. The system was designed to remove heat selectively and conductively from the sample volume through six of the eight tungsten carbide (WC) cubes in direct contact with the octahedralpressurecell. The key components of the system includeCu cooling fins sandwiched between neighboring cube faces and the connectedCu heat exchange chamber through which liquid nitrogen flows. Currently, this system enables us to reachtemperatures down to 220 K atpressures up to 8 GPa, but it can be easily m...
Source: Review of Scientific Instruments - December 6, 2016 Category: Physics Authors: Richard A. Secco and Wenjun Yong Source Type: research
Development of plasma assisted thermal vapor deposition technique for high-quality thin film
The novel technique of Plasma-Assisted VaporDeposition (PAVD) is developed as a newdeposition method for thinmetalfilms. The PAVD technique yields a high-qualitythin film without any heating of the substrate because evaporated particles acquire energy fromplasma that is confined to the inside of theevaporationsource. Experiments ofsilverthin film deposition have been carried out in conditions ofpressure lower than 10−3 Pa. Puresilverplasma generation is verified by the measurement of the Ag-I peak using optical emission spectroscopy. A four point probe and a UV-VIS spectrophotometer are used to measure the electrical and...
Source: Review of Scientific Instruments - December 6, 2016 Category: Physics Authors: Kang-Il Lee, Yong Sup Choi and Hyun Jae Park Source Type: research
Measurement of the electro-optic coefficient during the photoelectric-field assisted poling using a Mach-Zehnder interferometer
This work describes the experimental apparatus based on theMach-Zehnder interferometer formeasuring theelectro-optic coefficient during and after the photo-assisted poling process using a continuous light excitation. We also show that the poling can be performed at cryogenic temperatures. The setup is based on the superposition of aMach-Zehnder AC modulation voltage on theDC bias voltage required to promote the chromophore orientation during light excitation. Theeffect of the reversiblepolarization due to theDC bias voltage applied to thepolymer film is considered to calculate theelectro-optic coefficient during the photo-...
Source: Review of Scientific Instruments - December 6, 2016 Category: Physics Authors: Fl ávio M. Shimizu and José A. Giacometti Source Type: research
Research on ultra-fast vacuum mechanical switch driven by repulsive force actuator
In order to meet the fast operation demands of DC circuit breakers, a high-speed vacuum mechanical switch (VMS) driven by a repulsive force actuator is focused. To improve the drive speed and energy conversion efficiency (ECE) of the actuators, the dynamic characteristics of the double sidedcoil repulsive force actuators are investigated, and two generalizedoptimization design methods focusing on the aspect ratio of the drivingcoils (defined as ARF) and the electrical parameters (defined as EF) are developed.FEM simulation models ’ simulation and tests of VMS prototypes are conducted to verify theoptimization methods. Re...
Source: Review of Scientific Instruments - December 5, 2016 Category: Physics Authors: Zhao Yuan, Junjia He, Yuan Pan, Xin Jing, Canyi Zhong, Ning Zhang, Xiaoguang Wei and Guangfu Tang Source Type: research
Electrostatic energy harvesting device with dual resonant structure for wideband random vibration sources at low frequency
In this paper, we present design and test of a broadbandelectrostaticenergy harvester with a dualresonant structure, which consists of two cantilever-mass subsystems each with a mass attached at the free edge of a cantilever. Comparing to traditionaldevices with singleresonant frequency, the proposeddevice with dualresonant structure canresonate at two frequencies. Furthermore, when one of the cantilever-masses is oscillating atresonance, the vibration amplitude is large enough to make it collide with the other mass, which provides strong mechanical coupling between the two subsystems. Therefore, thisdevice can harvest a d...
Source: Review of Scientific Instruments - December 5, 2016 Category: Physics Authors: Yulong Zhang, Tianyang Wang, Ai Zhang, Zhuoteng Peng, Dan Luo, Rui Chen and Fei Wang Source Type: research
The method of pulsed x-ray detection with a diode laser
A new class of pulsedX-ray detection methods by sensing carrier changes in adiode lasercavity has been presented and demonstrated. The proof-of-principle experiments ondetecting pulsedX-ray temporal profile have been done through thediode laser with a multiple quantum well active layer. The result shows that our method can achieve the aim ofdetecting the temporal profile of a pulsedX-ray source. We predict that there is a minimum value for the pre-bias current of thediode laser by analyzing the carrier rate equation, which exists near the threshold current of thediode laser chip in experiments. This behaviour generally agr...
Source: Review of Scientific Instruments - December 5, 2016 Category: Physics Authors: Jun Liu, Xiaoping Ouyang, Zhongbing Zhang, Liang Sheng, Liang Chen, Xinjian Tan and Xiufeng Weng Source Type: research
Publisher ’s Note: “Transmission and fluorescence X-ray absorption spectroscopy cell/flow reactor for powder samples under vacuum or in reactive atmospheres” [Rev. Sci. Instrum. 87, 073108 (2016)]
(Source: Review of Scientific Instruments)
Source: Review of Scientific Instruments - December 2, 2016 Category: Physics Authors: A. S. Hoffman, L. M. Debefve, A. Bendjeriou-Sedjerari, S. Ould-Chikh, Simon R. Bare, J.-M. Basset and B. C. Gates Source Type: research
A new method for measuring the rotational accuracy of rolling element bearings
The rotational accuracy of amachine tool spindle has critical influence upon the geometric shape and surface roughness of finished workpiece. The rotational performance of the rolling element bearings is a main factor which affects the spindle accuracy, especially in the ultra-precisionmachining. In this paper, a new method is developed tomeasure the rotational accuracy of rolling element bearings ofmachine tool spindles. Variable andmeasurable axial preload is applied to seat the rolling elements in the bearing races, which is used to simulate the operating conditions. A high-precision (radial error is less than 300 nm) a...
Source: Review of Scientific Instruments - December 2, 2016 Category: Physics Authors: Ye Chen, Xiangsong Zhao, Weiguo Gao, Gaofeng Hu, Shizhen Zhang and Dawei Zhang Source Type: research
Tunable transportable spectroradiometer based on an acousto-optical tunable filter: Development and optical performance
We describe a high-performance, transportable, versatile spectroradiometer based on an acousto-optical tunable filter (AOTF). The instrument was developed fortemperature metrology, namely, to determine the thermodynamictemperature of black bodies above the Ag freezing point (961.78 °C). Its main design feature is the attenuation of thediffraction side lobes (and, thus, out-of-band stray light) thanks to the use of a double-pass configuration. Theradiofrequency tuning of the AOTF allows continuous, fine, and rapid wavelength control over a widespectral range (650 nm –1000 nm). The instrument tunability can be easily c...
Source: Review of Scientific Instruments - December 2, 2016 Category: Physics Authors: O. Kozlova, A. Sadouni, D. Truong, S. Briaudeau and M. Himbert Source Type: research
Mid-infrared gas absorption sensor based on a broadband external cavity quantum cascade laser
We developed a laserabsorptionsensor based on a pulsed, broadband tunable externalcavityquantum cascade laser (ECQCL) centered at 1285 cm−1. Unlike traditionalinfrared spectroscopy system, a quartz crystal tuning fork (QCTF) as a lightdetector was used for laser signaldetection. Fast Fourier transform was applied to extract vibration intensity information of QCTF. Thesensor system is successfully tested on nitrous oxide (N2O)spectroscopy measurements and compared with a standardinfrared detector. The wide wavelength tunability of ECQCL will allow us to access the fundamental vibrational bands of many chemical agents, whi...
Source: Review of Scientific Instruments - December 2, 2016 Category: Physics Authors: Juan Sun, Hao Deng, Ningwu Liu, Hongliang Wang, Benli Yu and Jingsong Li Source Type: research
Small optic suspensions for Advanced LIGO input optics and other precision optical experiments
We report on the design and performance of smallopticsuspensions developed to suppress seismic motion of out-of-cavityoptics in the inputoptics subsystem of the Advanced LaserInterferometer Gravitational WaveObservatory. These compact single stagesuspensions provide isolation in all six degrees of freedom of theoptic, local sensing and actuation in three of them, and passive damping for the other three. (Source: Review of Scientific Instruments)
Source: Review of Scientific Instruments - November 30, 2016 Category: Physics Authors: G. Ciani, M. A. Arain, S. M. Aston, D. Feldbaum, P. Fulda, J. Gleason, M. Heintze, R. M. Martin, C. L. Mueller, D. M. Nanda Kumar, A. Pele, D. H. Reitze, P. Sainathan, D. B. Tanner, L. F. Williams and G. Mueller Source Type: research
A simple approach to spectrally resolved fluorescence and bright field microscopy over select regions of interest
A standard wide field invertedmicroscope was converted to a spatially selective spectrally resolvedmicroscope through the addition of a polarizing beam splitter, a pair ofpolarizers, an amplitude-mode liquid crystal-spatial light modulator, and a USBspectrometer. The instrument is capable of simultaneously imaging and acquiringspectra over user defined regions of interest. Themicroscope can also be operated in a bright-field mode to acquireabsorption spectra of micron scale objects. The utility of the instrument is demonstrated on three different samples. First, the instrument is used to resolve three differently labeled f...
Source: Review of Scientific Instruments - November 29, 2016 Category: Physics Authors: Peter D. Dahlberg, Christopher T. Boughter, Nabil F. Faruk, Lu Hong, Young Hoon Koh, Matthew A. Reyer, Alon Shaiber, Aiman Sherani, Jiacheng Zhang, Justin E. Jureller and Adam T. Hammond Source Type: research
Absolute calibration of the OMEGA streaked optical pyrometer for temperature measurements of compressed materials
We present a simple closed-form equation for thebrightness temperature as a function of streak-camera signal derived from thiscalibration. Error estimates indicate thatbrightness temperature can be inferred to a precision of (Source: Review of Scientific Instruments)
Source: Review of Scientific Instruments - November 29, 2016 Category: Physics Authors: M. C. Gregor, R. Boni, A. Sorce, J. Kendrick, C. A. McCoy, D. N. Polsin, T. R. Boehly, P. M. Celliers, G. W. Collins, D. E. Fratanduono, J. H. Eggert and M. Millot Source Type: research
Real-time energy measurement of high repetition rate ultrashort laser pulses using pulse integration and FPGA processing
Real-time energy measurement using pulse integration method for high repetition rate ultrashort laser pulses based on FPGA (Field-Programmable Gate Array) and high-speed pipeline ADC (Analog-to-Digital Convertor) is introduced in this paper. There are two parts contained in this method: pulse integration and real-timedata processing. The pulse integration circuit will convert the pulse to the step type signals which are linear to the laser pulse energy. Through the real-timedata processing part, the amplitude of the step signals will be obtained by ADC sampling and conducting calculation in real time in FPGA. The test resu...
Source: Review of Scientific Instruments - November 29, 2016 Category: Physics Authors: Qi-jie Tang, Dong-xu Yang, Jian Wang, Yi Feng, Hong-fei Zhang and Teng-yun Chen Source Type: research
A novel system of coils for magnetobiology research
A novel system ofcoils fortestingin vitro magnetobiological effects was designed, simulated, and built. Opposite to what is usual, the system generates a controlled gradient ofmagnetic field. This feature is introduced to allow the assessment of multiple values of the field in a singleexperiment. The apparatus consists of two flattened orthogonalcoils, which permit independent control of two of the spatial components of the field. Geometry ofdesign, combined with the use of a standard multi-well microplate forcellular culture, allows for simultaneoustesting of 96 different field conditions. The system, intended to increase...
Source: Review of Scientific Instruments - November 29, 2016 Category: Physics Authors: L. Makinistian Source Type: research
