Scanning optical probe microscopy with submicrometer resolution using an organic photodetector
Kwang H. An, Brendan O'Connor, Kevin P. Pipe, Yiying Zhao, and Max Shtein
A high-resolution scanning optical microscopy technique is demonstrated, in which an organic photodetector on a silicon-based scanning probe cantilever scans a sample, simultaneously recording optical and topographic data with submicrometer resolution, while showing no measurable degradation during ... [Appl. Phys. Lett. 93, 033311 (2008)] published Wed Jul 23, 2008.
Scanning optical probe microscopy with submicrometer resolution using an organic photodetector
Kwang H. An, Brendan O'Connor, Kevin P. Pipe, Yiying Zhao, and Max Shtein
A high-resolution scanning optical microscopy technique is demonstrated, in which an organic photodetector on a silicon-based scanning probe cantilever scans a sample, simultaneously recording optical and topographic data with submicrometer resolution, while showing no measurable degradation during ... [Appl. Phys. Lett. 93, 033311 (2008)] published Wed Jul 23, 2008.
Real-time optical reflectometry enabled by amplified dispersive Fourier transformation
Keisuke Goda, Daniel R. Solli, and Bahram Jalali
The axial scan rate of optical frequency-domain reflectometry and optical coherence tomography can be increased to megahertz frequencies by dispersive Fourier transformation. However, the fundamental connection between dispersion and loss creates a trade-off between detection sensitivity and acquisi ... [Appl. Phys. Lett. 93, 031106 (2008)] published Wed Jul 23, 2008.
High-resolution 17--75 keV backlighters for high energy density experiments
H.-S. Park, B. R. Maddox, E. Giraldez, S. P. Hatchett, L. T. Hudson et al.
1775 keV one- and two-dimensional high-resolution (<10 [mu]m) radiography has been developed using high-intensity short pulse lasers. High energy Kalpha sources are created by fluorescence from hot electrons interacting in the target material after irradiation by lasers with intensity I>10 W/cm. ... [Phys. Plasmas 15, 072705 (2008)] published Wed Jul 23, 2008.
The near-field scanning thermal microscope
Uli F. Wischnath, Joachim Welker, Marco Munzel, and Achim Kittel
We report on the design, characterization, and performance of a near-field scanning thermal microscope capable to detect thermal heat currents mediated by evanescent thermal electromagnetic fields close to the surface of a sample. The instrument operates in ultrahigh vacuum and retains its scanning ... [Rev. Sci. Instrum. 79, 073708 (2008)] published Wed Jul 23, 2008.
Quantitative detection of DNA labeled with magnetic nanoparticles using arrays of MgO-based magnetic tunnel junction sensors
Weifeng Shen, Benaiah D. Schrag, Matthew J. Carter, and Gang Xiao
We have demonstrated the detection of 2.5 [mu]M target DNA labeled with 16 nm FeO nanoparticles (NPs) using arrays of magnetic tunnel junction sensors with (001)-oriented MgO barrier layers. A MTJ sensor bridge was designed to detect the presence of magnetic NPs bonded with target DNA. A raw signa ... [Appl. Phys. Lett. 93, 033903 (2008)] published Tue Jul 22, 2008.
Effect of geometry and multiple-image interactions on tunneling and I-V characteristics of metal-vacuum-metal point-contact junctions
N. M. Miskovsky, P. H. Cutler, T. E. Feuchtwang, S. J. Shepherd, A. A. Lucas et al.
A Green's function formalism has been used to obtain, for the first time, the exact multiple-image interactions for a hyperboloidal-tipplanar-anode model of a metal-whisker point-contact diode. I-V characteristics, including all image interactions, have been calculated for the point-contact junction ... [Appl. Phys. Lett. 37, 189 (2008)] published Tue Jul 22, 2008.
Comments on ''Determination and optimization of frequency response of constant temperature hot-wire anemometers in supersonic flows''
P. Freymuth
A practical limit for the value of low overheat is given. ... [Rev. Sci. Instrum. 51, 857 (2008)] published Tue Jul 22, 2008.
Simple interferometric instrument for evaluating the dynamic stress-optical coefficients and the ratio Poisson's ratio to modulus of elasticity
Demetrios D. Raftopoulos and Stamatios V. Kartalopoulos
A simple prototype opto-electronic-mechanical instrument has been designed and constructed in order to measure optical and mechanical properties of transparent materials. ... [Rev. Sci. Instrum. 51, 853 (2008)] published Tue Jul 22, 2008.
Convenient thermal/vapor barrier for constant temperature water bath
John S. Huang and Mahn Won Kim
We report a simple scheme to install an effective thermal/vapor barrier for precision temperature baths. We have found that by floating on the water surface, a pile of common packing material such as styrofoam pellets fused together by a solvent spray, a ten-fold reduction in the bath temperature fl ... [Rev. Sci. Instrum. 51, 852 (2008)] published Tue Jul 22, 2008.
Simple parallel interface between an optical multichannel analyser detector controller and a microprocessor
Stephen E. Bialkowski
A simple circuit is given which will allow data transfer from a LSI-11 DRV11 parallel interface unit to a PARC 1216 Optical Multichannel Detector Controller. The Circuit for OMA to LSI-11 data transfer is slightly more complicated. Data buffering is used so that data transfer can occur without time- ... [Rev. Sci. Instrum. 51, 850 (2008)] published Tue Jul 22, 2008.
Pressure distribution in gaskets of high pressure devices
J. Kamarad
The values of the coefficient of internal friction [mu] and the yield stress sigma of materials which are used in gaskets of high pressure devices, are given. The mathematical expressions, based on the analysis of the real pressure distribution in the gasket of Bridgman anvils enables one to calcula ... [Rev. Sci. Instrum. 51, 848 (2008)] published Tue Jul 22, 2008.
Some properties of Nuclepore filters
Tar-pin Chen, Michael J. DiPirro, Bidyut Bhattacharyya, and Francis M. Gasparini
We present the results of various measurements we have made to characterize Nuclepore filters. These include nitrogen and helium adsorption isotherms, heat capacity and SEM studies of pore size distribution and pore density. ... [Rev. Sci. Instrum. 51, 846 (2008)] published Tue Jul 22, 2008.
High isolation duplexing switch for a pulsed NMR spectrometer
Chester O. Britt, Tony C. Moore, and Chas. G. Wade
A duplexing switch for a pulsed NMR spectrometer is described which produces high isolation and low loss when used as the series switch. ... [Rev. Sci. Instrum. 51, 845 (2008)] published Tue Jul 22, 2008.
Design and performance of a UHV fatigue drive
T. K. G. Swami and Y. W. Chung
A simple fatigue drive that permits fatiguing of specimens in the flexural mode at rates up to 30 Hz under ultrahigh vacuum conditions has been built and successfully tested in fatigue-enhanced photoemission studies. ... [Rev. Sci. Instrum. 51, 842 (2008)] published Tue Jul 22, 2008.
High pressure and low temperature cell for x-ray diffuse scattering studies
A. H. Moudden, L. Gatebois, F. Denoyer, and M. Lambert
We present the details of design and construction of a high pressure cell for x-ray diffuse scattering experiments up to 5 kbar and down to 77 degrees K. Exciting preliminary results on thiourea are presented as a test of its performance. ... [Rev. Sci. Instrum. 51, 836 (2008)] published Tue Jul 22, 2008.
Intensity dependent time resolution and dynamic range of photochron picosecond streak cameras II. Linear photoelectric recording
D. J. Bradley, S. F. Bryant, and W. Sibbett
By using an optical multichannel analyser to replace film as the recording medium a completely linear recording streak camera has been constructed with a time resolution of less than 3 ps, and an improved dynamic range of ~150. It has also been found possible to dispense with an image intensifier an ... [Rev. Sci. Instrum. 51, 824 (2008)] published Tue Jul 22, 2008.
Proportional response photon counter
S. Mitra, A. K. Sinha, and S. C. Roy
A scintillation counter whose detection efficiency is linearly proportional to the energy of the interacting photon has been developed by combining a suitable filter with a conventional NaI(Tl) crystal. A general theory has been developed from which the material and optimum filter thickness for a pa ... [Rev. Sci. Instrum. 51, 821 (2008)] published Tue Jul 22, 2008.
Stopped-flow apparatus for the study of fast reactions in solution under high pressure.
K. Heremans, J. Snauwaert, and J. Rijkenberg
A stopped flow apparatus is described to study fast reactions in solution up to 1.2 kbar. The reaction course is followed optically. The apparatus is capable of measuring reactions with a half life of 20 ms. ... [Rev. Sci. Instrum. 51, 806 (2008)] published Tue Jul 22, 2008.
Use of nonlinear least mean squares fitting to achieve compensated electrical filters
Ann H. Sanders and David S. Cannell
The results of using nonlinear least-mean-squares fitting procedures to compensate passive electrical filters for the effects of frequency-dependent losses in the inductors by changes in the other components are reported. This technique, when applied to third- and fifth-order low-pass Chebysheff fil ... [Rev. Sci. Instrum. 51, 799 (2008)] published Tue Jul 22, 2008.
Computer controlled absorption spectrometer for gas phase samples
F. W. Arndt and J.Robert Huber
A computer controlled absorption spectrometer featuring a rotating tube which contains the sample and reference cells is described. The high sensitivity of this instrument makes it suitable for dilute gasphase absorption measurements. ... [Rev. Sci. Instrum. 51, 786 (2008)] published Tue Jul 22, 2008.
Time dependence of rate-dependent photomultiplier gain and its implications
Mikio Yamashita
Time dependences of rate-dependent photomultiplier gain were measured precisely in two particular tubes for various count rate changes. Most of the measured time dependences are shown to be well described by three exponential components. While the corresponding time constants remain unchanged for di ... [Rev. Sci. Instrum. 51, 768 (2008)] published Tue Jul 22, 2008.
Digital data acquisition and analysis of striated muscle diffraction patterns with a direct memory access microprocessor system
Kenneth P. Roos, Ronald J. Baskin, Richard L. Lieber, James W. Cline, and Paul J. Paolini
A microprocessor based data acquisition computing system has been developed to examine dynamic changes in light diffraction patterns from single skeletal muscle fibers. A significant improvement in digital data acquisition rate compared to previous designs has been achieved by utilizing a fast dedic ... [Rev. Sci. Instrum. 51, 762 (2008)] published Tue Jul 22, 2008.
Optimized linear variable differential transformer displacement transducer for cryogenic use
N. C. Sponagle and D. L. Atherton
A simple procedure is given for optimizing the performance and coil dimensions of an Ellis and Walstrom type moving coil, linear variable differential transformer displacement transducer as well as a method of compensating for changes in calibration at different operating temperatures. The resulting ... [Rev. Sci. Instrum. 51, 759 (2008)] published Tue Jul 22, 2008.
Application of sintered diamond tipped ultra high pressure apparatus to cryogenic experiments
F. P. Bundy and K. J. Dunn
The sintered diamond tipped, opposed piston, ultra high pressure apparatus developed in this laboratory in 1975 has been adapted to cryogenic experimentation by replacing the steel binding rings with nonbrittle stainless steel ones, and by providing it with a special stainless steel, squirrel-cage t ... [Rev. Sci. Instrum. 51, 753 (2008)] published Tue Jul 22, 2008.
Method for the measurement of temperature in shock compression of solids
Hiroshi Sugiura, Ken-ichi Kondo, and Akira Sawaoka
A new optical measurement method for obtaining the temperature of solids during shock compression has been developed. Spectral measurements of thermal radiation produced during shock compression of fused silica have been made, and the shock temperature estimated from the spectrum. This method is les ... [Rev. Sci. Instrum. 51, 750 (2008)] published Tue Jul 22, 2008.
Flash x-ray tube for diffraction studies on a two-stage light-gas gun
Quintin Johnson, A. C. Mitchell, and Ian D. Smith
A flash x-ray tube has been fabricated and has been driven by a Blumlein pulse generator to peak voltages of 60 to 80 kV and peak anode currents of 8 to 10 kA. The pulse width, dependent upon the anode-cathode spacing, can be made ~80-ns wide, and a small spot or line focus is possible. These featur ... [Rev. Sci. Instrum. 51, 741 (2008)] published Tue Jul 22, 2008.
Technique for measuring cooling patterns in ion source grids by infrared scanning
L. R. Grisham, H. P. Eubank, and H. W. Kugel
Many plasma souces designed for neutral beam injection heating of plasmas now employ copper beam acceleration grids which are water cooled by small capillary tubes fed from one or more headers. To prevent thermally-induced warpage of these grids it is essential that one be able to detect inhomogenei ... [Rev. Sci. Instrum. 51, 738 (2008)] published Tue Jul 22, 2008.
Quasi--dc extraction of 70 keV, 5 A ion beam
Y. Okumura, S. Matsuda, Y. Mizutani, Y. Ohara, and T. Ohga
An ion source that produces a high energy ion beam in quasi-dc mode has been fabricated and tested. The significant features of the source are effectively cooled accelerator grids with properly shaped apertures and a carefully cooled douPIGatron plasma generator. To opeate the source quasi-continuou ... [Rev. Sci. Instrum. 51, 728 (2008)] published Tue Jul 22, 2008.
Multicusp negative ion source
K. W. Ehlers and K. N. Leung
The characteristics of a steady state, surface conversion, multiline-cusp negative ion source have been investigated for the production of high-energy neutral beams. With the presence of cesium, this source has been operated at a neutral pressure of 1 x 10 Torr to generate a H ion current greater th ... [Rev. Sci. Instrum. 51, 721 (2008)] published Tue Jul 22, 2008.
Intense 3 ns neutron source
J. Chang and R. J. Leeper
A 3 ns pulsed beam-target neutron source has been developed to simulate a thermonuclear neutron burst from an inertial confinement fusion target. The yield from the neutron source is equivalent to an isotropic source producing ~3 x 10 DD and ~2 x 10 DT neutrons into 4 pi steradians per pulse. The un ... [Rev. Sci. Instrum. 51, 715 (2008)] published Tue Jul 22, 2008.
Electron energy loss microanalysis system with high collection efficiency
Dale E. Johnson
An electron energy loss spectrometry system is described in which the lenses of an electron microscope are used with a straight edge magnetic sector energy analyzer to significantly improve the performance over that of the magnetic sector alone. An order of magnitude improvement in performance is de ... [Rev. Sci. Instrum. 51, 705 (2008)] published Tue Jul 22, 2008.
System for combined SIMS-AES-XPS studies of solids
M. A. Frisch, W. Reuter, and K. Wittmaack
We have have assembled a system for combined surface and thin film studies by SIMS, AES and XPS. The SIMS and AES investigations are performed in the same UHV chamber, while for XPS measurements the sample is transfered into the XPS system via an isolation valve. The SIMS-AES and XPS units can be op ... [Rev. Sci. Instrum. 51, 695 (2008)] published Tue Jul 22, 2008.
Simple, fast rise time, high repetition rate Pockels cell driver
B. Plourde, M. E. Mack, and E. Verro
A thyratron Pockels cell driver capable of optically switching Pockels cells of up to 2.5 cm aperture in 6 ns at repetition rates of up to 1000 Hz is described. The circuit is based on a modified HY-2 thyratron. ... [Rev. Sci. Instrum. 51, 549 (2008)] published Tue Jul 22, 2008.
Design of a guarded electrode
R. E. Collins and O. R. French
A simple technique is described for constructing a plane guarded electrode which has a very small gap between electrode and guard ring. ... [Rev. Sci. Instrum. 51, 547 (2008)] published Tue Jul 22, 2008.
Broad beam ion source operation with four common gases
S. Pak and J. R. Sites
A Kaufman-type broad beam ion source, used for sputtering and etching purposes, has been operated with Ar, Kr, O and N gas inputs over a wide range of beam energies (2001200 eV) and gas flow rates (110 sccm). The maximum ion beam current density for each gas saturates at about 2.5 mA/cm as gas flow ... [Rev. Sci. Instrum. 51, 536 (2008)] published Tue Jul 22, 2008.
High pressure apparatus for PVT measurements of liquids and plastic crystals at low temperatures
R. Landau and A. Wurflinger
A high pressure apparatus for determining PVT data of liquids and plastic crystals and volume changes which might accompany phase transitions is described. In the present investigation the PVT data of acetonitrile have been determined from +40 degrees to 50 degrees C and up to 3000 bar, including ... [Rev. Sci. Instrum. 51, 533 (2008)] published Tue Jul 22, 2008.
High efficiency melting furnace
H. G. Riveros, W. K. Cory, R. Toca, and E. Cabrera
With a hot plate and a spherical mirror, a highly efficient crucible heating furnace was theoretically calculated and constructed. The upper part of the crucible provides free access to the melt, as is needed in the Czochralski crystal growth technique. For the design, the heat radiation flow betwee ... [Rev. Sci. Instrum. 51, 528 (2008)] published Tue Jul 22, 2008.
A magnetic-reluctance thickness gauge for high conductivity, ferromagnetic films
S. R. Ryan and A. R. Ryan
A magnetic comparator for measuring the thickness of high conductivity, ferromagnetic films is described. The instrument compares the reluctance of a standard sample to that of a film of unknown thickness at the same value of magnetic field intensity to insure that the permeability is the same for b ... [Rev. Sci. Instrum. 51, 521 (2008)] published Tue Jul 22, 2008.
High precision [sup 3]He-vapor-pressure gauge for use to 0.3 K
D. S. Greywall and P. A. Busch
The design and performance of a compact, high precision, capacitive, vapor-pressure gauge is described. The gauge was constructed using a thin electrodeposited copper diaphragm. ... [Rev. Sci. Instrum. 51, 509 (2008)] published Tue Jul 22, 2008.
Low energy ion beam transport by permanent magnets
K. W. Ehlers and K. N. Leung
The guiding of a 300 eV divergent hydrogen ion beam by a surface magnetic field generated by samarium cobalt magnets has been investigated. It was found that magnets arranged in a multi-ring-cusp configuration produced the best beam transport efficiency. ... [Rev. Sci. Instrum. 51, 500 (2008)] published Tue Jul 22, 2008.
The GaAs spin polarized electron source
D. T. Pierce, R. J. Celotta, G.-C. Wang, W. N. Unertl, A. Galejs et al.
The design, construction, operation, and performance of a spin polarized electron source utilizing photoemission from negative electron affinity (NEA) GaAs are presented in detail. A polarization of 432% is produced using NEA GaAs (100). The polarization can be easily modulated without affecting oth ... [Rev. Sci. Instrum. 51, 478 (2008)] published Tue Jul 22, 2008.
Surface ionization source for heavy ions
B. Rasser, D. I. C. Pearson, and M. Remy
An ion source using the surface ionization process is described. Elements whose ionization potentials are below or around 6 eV may be ionized in the source. The element vapour to be ionized is passed through one or more rhenium grids on which surface ionization occurs. The source is tested for diffe ... [Rev. Sci. Instrum. 51, 474 (2008)] published Tue Jul 22, 2008.
Experimental study of ion beamlet steering by aperture displacement in two-stage accelerator
Y. Okumura, Y. Mizutani, and Y. Ohara
The steering of ion beamlets in a two-stage accelerator has been measured as functions of both aperture displacement and field intensity ratio between extraction and acceleration regions. Three different types of displacement have been investigated; i.e., displacement of (1) plasma grid, (2) gradien ... [Rev. Sci. Instrum. 51, 471 (2008)] published Tue Jul 22, 2008.
Random array grid collimators
E. E. Fenimore and R. L. Blake
X-ray collimators using grid patterns which are random offer several significant advantages over collimators using periodic grids. In particular, random array grid collimators (RAGC's) eliminate the requirement that there be very closely spaced grids if a wide field of obscuration outside the centra ... [Rev. Sci. Instrum. 51, 445 (2008)] published Tue Jul 22, 2008.
Detection of cathodoluminescence of Giemsa stain and its applications
S. Basu
Giemsa stain shows an intense and durable cathodoluminescence (CL) when studied at 2030 kV with a quartz transmission light pipephotomultiplier system in a scanning electron microscope. Clear CL images of Giemsa-stained chromatin, nuclei, and chromosomes were recorded at low electron does (approxima ... [Rev. Sci. Instrum. 51, 435 (2008)] published Tue Jul 22, 2008.
Microcomputer-based data acquisition and stabilization system for piezoelectrically scanned Fabry-Perot interferomter
Masayoshi Yamada, Hiroyuki Ikeshima, and Yutaka Takahashi
A microcomputer-based data acquisition and stabilization system is presented for piezoelectrically scanned plane-parallel Fabry-Perot interferometers which typically required some form of active stabilization system for long-term operation. The microcomputer takes the place of the programable ramp g ... [Rev. Sci. Instrum. 51, 431 (2008)] published Tue Jul 22, 2008.
Fast pulsed gas valve
C. J. Keyser, M. Dembinski, and P. K. John
A fast valve which can inject gas pulses with durations from 25 to 400 [mu]s into a vacuum system is described. Quantities up to 5 Torr l can be injected. A pressure rise time of ~0.5 Torr/[mu]s has been determined at the valve opening. A fast opening time is achieved by having a magnetically accele ... [Rev. Sci. Instrum. 51, 425 (2008)] published Tue Jul 22, 2008.
Beamlet steering by aperture displacement in ion sources with large acceleration-deceleration ratio
J. R. Conrad
The steering of ion beamlets by aperture displacement is studied analytically and numerically for the case of triode extractors with large acceleration-deceleration ratios. Here the acceleration-deceleration ratio epsilon is defined by epsilon[equivalent]V/V, where V and V are the potentials applied ... [Rev. Sci. Instrum. 51, 418 (2008)] published Tue Jul 22, 2008.
Heat capacity cryostat and novel methods of analysis for small specimens in the 1.5--10 K range
E. M. Forgan and S. Nedjat
We describe a method for measuring heat capacity of small specimens in the 1.510 K range by means of thermal relaxation over that range. Our methods of calibration and analysis make use of the simple properties of the thermal link between specimen and its surroundings, and offer several advantages. ... [Rev. Sci. Instrum. 51, 411 (2008)] published Tue Jul 22, 2008.
Inserting thermocouples directly through infrared windows
Clifton W. Draper and William O. Pessel
Small holes, approximately 0.25 mm diameter, are drilled through IR windows (NaCl, KCl, CsBr) 3.2 mm thick. Thermocouples wires (0.13 mm diam) are inserted and sealed with ''Vacseal,'' a silicone resin. After curing, a reasonably durable-vacuum proof seal exits. The method provides a very simple, in ... [Rev. Sci. Instrum. 51, 258 (2008)] published Tue Jul 22, 2008.
Economical replacement for gold O-ring type gaskets in metal vacuum systems
Edward M. Beaver
A technique for fabricating O-ring type gaskets from electrical utility wire is described, including criteria for successful welds using facilities readily available in the average laboratory. ... [Rev. Sci. Instrum. 51, 254 (2008)] published Tue Jul 22, 2008.
High pressure pressure-jump apparatus
K. Heremans, F. Ceuterick, and J. Rijkenberg
A pressure jump relaxation technique is described to study fast reactions in solution under pressure up to 1.5 kbar. The mechanical relaxation time of the instrument is 0.5 ms. ... [Rev. Sci. Instrum. 51, 252 (2008)] published Tue Jul 22, 2008.
Circuit for the measurement of surface potential changes by the static capacitor method
R. W. Pasco and P. J. Ficalora
Circuitry is presented for the measurement of surface potential changes upon adsorption of gases on a metal foil or film by the static capacitor method. The circuit operates in the usual manner applying a backing off potential which opposes the flow of current from the cell comprised of the foil or ... [Rev. Sci. Instrum. 51, 246 (2008)] published Tue Jul 22, 2008.
Highly flexible pulse programmer for NMR applications
J. Dart, D. P. Burum, and W. K. Rhim
A pulse generator for NMR application is described. Eighteen output channels are provided to allow use in both single and double resonance experiments. Complex pulse sequences may be generated by loading instructions into a 256-word by 16-bit program memory. Features of the pulse generator include p ... [Rev. Sci. Instrum. 51, 224 (2008)] published Tue Jul 22, 2008.
Precision two-compartment bomb calorimeter for combustion in fluorine
H. Lenski and D. Bohler
An isothermally jacketed liquid calorimeter permitting thermochemical studies on spontaneous combustion in fluorine has been built and tested. The fluorine storage tank was located outside the calorimeter vessel, thus lowering the heat capacity of the system and its thermal inertia. Particular atten ... [Rev. Sci. Instrum. 51, 221 (2008)] published Tue Jul 22, 2008.
Mechanical aids for the alignment of four-circle single-crystal diffractometers
Stephen Guggenheim and Joseph Schreckeis
Two simple mechanical devices are described to aid in the alignment of x-ray four-circle single-crystal diffractometers. The first is a table mounted on the goniostat for use as a reference plane; the second a telescoping pointer for positioning the collimators. Suggestions for use are applied to a ... [Rev. Sci. Instrum. 51, 1138 (2008)] published Tue Jul 22, 2008.
A method for measuring small rotational velocities for a couette-type viscometer
John G. Berberian
A parallel plate capacitor assembly is used to measure the angular rotation in viscosity measurements using a Couette-type viscometer. This measurement coupled with a time base permits extremely small angle velocities to be measured thus permitting large viscosities (ca. 10 Pa s) to be determined. S ... [Rev. Sci. Instrum. 51, 1136 (2008)] published Tue Jul 22, 2008.
Inexpensive timing circuit for a Q-switched solid-state laser using NE555 Timers
N. Subhash and K. Sathianandan
A simple circuit using NE555 Timers for controlling a low repetition rate (upto 10 pulses/min.) Q-switched solid-state laser is described. This circuit produces two pulses, one for firing the flashlamp and the other for driving the electro-optic Q-switch, whose delay can be continuously varied up to ... [Rev. Sci. Instrum. 51, 1130 (2008)] published Tue Jul 22, 2008.
Simple electron beam guiding system including automatic capture circuitry
W. Stein, M. Schulenburg, and F. Freund
The spatial stability of the point of impact of an electron beam is a stringent requirement in some experiments such as soft x-ray spectroscopy using a focussing curved crystal spectrometer. The occasinally poor design of moderately priced electron guns, thermal instabilities, electromagnetic stray ... [Rev. Sci. Instrum. 51, 1126 (2008)] published Tue Jul 22, 2008.
Simple analytic method for microwave cavity Q determination
Zdenek Frait and Carl E. Patton
A simple method for the accurate determination of the quality factor, Q, of a reflection microwave cavity is described. ... [Rev. Sci. Instrum. 51, 1092 (2008)] published Tue Jul 22, 2008.
A wide range high sensitivity film balance
Bernard M. Abraham, Kenjiro Miyano, Kurt Buzard, and John B. Ketterson
A film balance has been constructed that features a wide range (~80 dynes/cm) and high sensitivity (~10 dyne/cm). The device is rugged, simple to operate and can be repeatedly assembled/disassembled in cycles (for cleanings) without affecting its mechanical parameters (nullpoint and sensitivity). ... [Rev. Sci. Instrum. 51, 1083 (2008)] published Tue Jul 22, 2008.
High sensitivity pulse-counting mass spectrometer system for noble gas analysis
C. M. Hohenberg
A pulse-counting mass spectrometer is described which is comprised of a new ion source of cylindrical geometry, with exceptional optical properties (the Baur source), a dual focal plane externally adjustable collector slits, and a 17-stage Allen-type electron multiplier, all housed in a metal 21 cm ... [Rev. Sci. Instrum. 51, 1075 (2008)] published Tue Jul 22, 2008.
High current source of He[sup - ] ions
E. B. Hooper, Jr, P. A. Pincosy, P. Poulsen, C. F. Burrell, L. R. Grisham et al.
A negative helium ion beam of 70 mA at 10.5 kV has been produced by charge exchange in sodium. The production is studied as a function of sodium line density, beam energy and background helium gas density. The characteristics of this high current He source are analyzed to determine the design requir ... [Rev. Sci. Instrum. 51, 1066 (2008)] published Tue Jul 22, 2008.
Instrumentation for the size determination of submicron particulates systems by sideway light scattering method
K. Suda
A new submicron particle counter using a low output HeNe laser (unpolarized, 8 mW) is proposed for in situ measurement of particulates. The design is based on calculations and experimental checks of factors governing the signal-to-noise ratio. Right angle scattering is found to be the most suitalbe ... [Rev. Sci. Instrum. 51, 1049 (2008)] published Tue Jul 22, 2008.
High pressure stopped-flow apparatus for the rapid mixing and subsequent study of two fluids under high hydrostatic pressures
Daniel M. Karan and Robert I. Macey
A stopped-flow apparatus is described for the rapid mixing and subsequent study of two dissimilar fluids under pressures up to 1200 bar. The device consists of two identical pressure chambers which contain the two fluids, a third pressure chamber which contains gas to maintain the pressure in the sy ... [Rev. Sci. Instrum. 51, 1042 (2008)] published Tue Jul 22, 2008.
Speer carbon resistors as pressure gauges
S. M. Wasim, R. Aldana, and F. Cabrera
A study has been made of the resistance pressure characteristics of a number of Speer carbon resistors in the temperature range between 295 K and 76 K under hydrostatic pressure of up to 10.5 kbar. It is found that the resistance of the resistors decreases markedly with pressure. The results are qui ... [Rev. Sci. Instrum. 51, 1040 (2008)] published Tue Jul 22, 2008.
Improved pressure calibration system using the ruby R[sub 1] fluorescence
Hubert E. King, Jr and Charles T. Prewitt
When measuring pressures in the diamond anvil cell, undersirable line broadening and wavelength shifts result if small ruby crystals are used in a calibration system designed for large ones. These effects can be eliminated through the proper choice of objective lens, condensing lens, and slit system ... [Rev. Sci. Instrum. 51, 1037 (2008)] published Tue Jul 22, 2008.
An automated relaxation calorimeter with extended temperature range
B. F. Griffing and S. A. Shivashankar
A computer-automated thermal relaxation calorimeter for use in the temperature range 4380 K is described. The system can be utilized to make absolute measurements on fairly small (20 mg.) samples which may be of low thermal conductivity. A new hybrid sweep-decay mode of operation for measuring heats ... [Rev. Sci. Instrum. 51, 1030 (2008)] published Tue Jul 22, 2008.
Curved-crystal (LiF) x-ray focussing array for fluorescence EXAFS in dilute samples
M. Marcus, L. S. Powers, A. R. Storm, B. M. Kincaid, and B Chance
A focussing monochromator array for detection of fluorescence EXAFS (Extended Xray Absorption Edge Fine Structure) is described. The array is made of LiF crystals, specially prepared for large mosaic spread. Design criteria, performance specifications, and details of fabrication and crystal preparat ... [Rev. Sci. Instrum. 51, 1023 (2008)] published Tue Jul 22, 2008.
Wheatstone bridge fed from a bilateral constant current source
C. Velayudhan and Daniel Oommen
A simple inexpensive scheme of an electronic amplifier for Wheatstone bridge application is presented. The bridge is excited from a bilateral constant current square wave source. The advantage of constant current drive is presented. ... [Rev. Sci. Instrum. 51, 397 (2008)] published Tue Jul 22, 2008.
Low energy ion counting efficiency of a Johnston electron multiplier
R. E. Stickel, Jr., F. G. Kellert, K. A. Smith, F. B. Dunning, and R. F. Stebbings
We report a measurement of the absolute efficiency of a Johnston Laboratories MMl electron multiplier for detection of 24 keV Ne. The measured detection efficiency depends both on ion impact energy and on the magnitude and direction of an externally applied electric field near the first dynode. ... [Rev. Sci. Instrum. 51, 396 (2008)] published Tue Jul 22, 2008.
Some modifications of electric circuitry for internal friction measurements of U-shape specimens
O. Yoshinari, M. Koiwa, H. Sugawara, and I. Satoh
Some modifications of the electric circuitry are described for the apparatus of the internal friction measurement of thin wire specimens; the apparatus has been developed by Franklin et al. The improved apparatus has been successfully used in the internal friction measurements of cold-worked vanadiu ... [Rev. Sci. Instrum. 51, 394 (2008)] published Tue Jul 22, 2008.
Sample cell for EXAFS measurements on molten materials at elevated temperatures
J. C. Mikkelsen, Jr., J. B. Boyce, and R. Allen
We describe the design, fabrication, and utilization of a simple sample cell for extended x-ray absorption fine structure (EXAFS) measurements at elevated temperature. The cell is rigid, inert, easy to fabricate, cheap and effective in maintaining the critical specimen dimensions of both solid and l ... [Rev. Sci. Instrum. 51, 388 (2008)] published Tue Jul 22, 2008.
Adaptation of an ultrahigh vacuum angle-resolving photoemission chamber for sample manipulation and rotation
W. A. Royer
A sample-manipulator attachment to a UHV angle-resolving photoemission system is described which permits the sample to be rotated azimuthally and to be transported to a LEED/Auger optics. The manipulator may be assembled from readily available commercial parts. ... [Rev. Sci. Instrum. 51, 386 (2008)] published Tue Jul 22, 2008.
Wheatstone bridge technique for magnetostriction measurements
Michael Sullivan
A basic Wheatstone bridge, with additional electronic instrumentation, has been used in the measurement of magnetostriction. This method allows a resolution of ~10% on measurements of magnetostrictions less than 0.75 parts per million. ... [Rev. Sci. Instrum. 51, 382 (2008)] published Tue Jul 22, 2008.
Construction of a new unclipped digital correlator for quasielastic light scattering
Walter Lempert and C. H. Wang
An unclipped digital correlator that we have built has been described. Our digital correlator can be easily incorporated (with only a moderate cost) in an established light scattering laboratory equipped with a computer. ... [Rev. Sci. Instrum. 51, 380 (2008)] published Tue Jul 22, 2008.
Mechanical properties of Stycast-1266 at low temperatures
Tatsuo Hashimoto and Akira Ikushima
Young's modulus, the critical tensile stress, and the fracture stress of Stycast-1266 have been determined by the tension test as functions of temperature between room temperature and 2.2 K. ... [Rev. Sci. Instrum. 51, 378 (2008)] published Tue Jul 22, 2008.
Bifurcated fiber luminometer
R. E. Grojean and J. A. Sousa
Measurements of luminescence in turbid media or in situ at inaccessible or hazardous locations is facilitated through the use of a random, bifurcated optical fiber bundle. ... [Rev. Sci. Instrum. 51, 377 (2008)] published Tue Jul 22, 2008.
Narrow energy distribution of output electrons from a modified single channel electron multiplier
Nobuyoshi Koshida, Makoto Kunii, and Shigetomo Yoshida
New methods which reduce the unfavorable energy spread of output electrons from a single channel electron multiplier are presented. A modified output electrode produces a pronounced narrowing effect on the energy distribution without much affect on the gain. A simplified analysis of the field inside ... [Rev. Sci. Instrum. 51, 365 (2008)] published Tue Jul 22, 2008.
Effect of heat leaks in platinum resistance thermometry
E. Goldratt, Y. Yeshurun, and A. J. Greenfield
The effect of heat leaks in platinum resistance thermometry is analyzed. An experimental method is proposed for estimating the magnitude of this effect. Results are reported for the measurement of the temperature of a hot, solid body under different heat-leak configurations. Design criteria for ther ... [Rev. Sci. Instrum. 51, 361 (2008)] published Tue Jul 22, 2008.
Two-filter monitor for atmospheric [sup 222]Rn
S. D. Schery, D. H. Gaeddert, and M. H. Wilkening
A two-filter, continuous monitor has been developed for atmospheric Rn. Features include a sensitivity of better than 0.01 pCi/l, a high specificity for Rn, and immediate start up capability. The monitor has been computer modeled to facilitate calibration and selection of operating parameters. The f ... [Rev. Sci. Instrum. 51, 338 (2008)] published Tue Jul 22, 2008.
Automatic, tracking, peak timer
D. J. Holcomb and T. Koczynski
We have designed an inexpensive instrument for automatically measuring time of flight for repetitive signals. It is stable in the presence of noise resembling the real signal. Specific peaks in a multipeak signal can be timed to an accuracy of about 10 ns with the present design. The output is eithe ... [Rev. Sci. Instrum. 51, 310 (2008)] published Tue Jul 22, 2008.
Multiscaler-microcomputer interface
Leo Wolpert
An interface which enables data transfer to or from a microcomputer is described. Data transfer from an analyser uses the printer output under interface control. To put the processed data into a form acceptable to the analyser, the output of the microcomputer is converted by the interface into pulse ... [Rev. Sci. Instrum. 51, 299 (2008)] published Tue Jul 22, 2008.
A fully stabilized Brillouin spectrometer with high contrast and high resolution
R. Vacher, H. Sussner, and M. v. Schickfus
Using a triple-pass plane and a confocal FabryPerot interferometers in tandem, we have constructed a Brillouin spectrometer with a frequency resolution of 10 and a contrast of more than 10. Our system is controlled and fully stabilized by a desktop calculator, allowing efficient data collection for ... [Rev. Sci. Instrum. 51, 288 (2008)] published Tue Jul 22, 2008.
Tunable laboratory extended x-ray absorption fine structure system
G. G. Cohen, D. A. Fischer, J. Colbert, and N. J. Shevchik
A new sensitive x-ray monochromator and detector system for performing extended x-ray absorption fine structure (EXAFS) measurements in the laboratory is described. The monochromator combines x-ray focusing optics with rapid elemental tunability. The detection system effectively removes glitches fro ... [Rev. Sci. Instrum. 51, 273 (2008)] published Tue Jul 22, 2008.
IR pyrometry in diamond anvil cell above 400 K
P. Shuker, A. Melchior, Y. Assor, D. Belker, and E. Sterer
Temperature measurements in a laser heated diamond anvil cell (DAC) are currently limited to temperatures above 1000 K using optics and detectors in the visible range. We have built a pyrometer in the IR range and expanded the lower limit of temperature detection to 400 K. The pyrometer is designe ... [Rev. Sci. Instrum. 79, 073908 (2008)] published Tue Jul 22, 2008.
Invited Review Article: Accurate and fast nanopositioning with piezoelectric tube scanners: Emerging trends and future challenges
S. O. Reza Moheimani
Piezoelectric tube scanners have emerged as the most widely used nanopositioning technology in modern scanning probe microscopes. Despite their impressive properties, their fast and accurate operations are hindered due to complications such as scan induced mechanical vibrations, hysteresis nonlinear ... [Rev. Sci. Instrum. 79, 071101 (2008)] published Tue Jul 22, 2008.
Toner Penetration into Porous Substrates
Elina Hakola, Jorma Koskinen, Ulla Forsstrom, and Pirkko Oittinen
The penetration of toner into porous substrates is studied using cross sections and topographical maps of the toner layer. Toner penetrates readily into the pores of the substrate and the penetration depth is larger than previously stated. As the toner enters the fixing stage, its temperature increa ... [J. Imaging Sci. Technol. 52, 040501 (2008)] published Fri Jul 18, 2008.
Multivariate statistical projection methods to perform robust feature extraction and classification in surface grading
Jose Manuel Prats-Montalban, Fernando Lopez, Jose M. Valiente, and Alberto Ferrer
We present an innovative way to simultaneously perform feature extraction and classification for the quality-control issue of surface grading by applying two multivariate statistical projection methods: SIMCA and PLS-DA. These tools have been applied to compress the color texture data that describe ... [J. Electron. Imaging 17, 031106 (2008)] published Fri Jul 18, 2008.
On-chip integration of high-frequency electron paramagnetic resonance spectroscopy and Hall-effect magnetometry
H. M. Quddusi, C. M. Ramsey, J. C. Gonzalez-Pons, J. J. Henderson, E. del Barco et al.
A sensor that integrates high-sensitivity micro-Hall effect magnetometry and high-frequency electron paramagnetic resonance spectroscopy capabilities on a single semiconductor chip is presented. The Hall-effect magnetometer (HEM) was fabricated from a two-dimensional electron gas GaAs/AlGaAs heteros ... [Rev. Sci. Instrum. 79, 074703 (2008)] published Fri Jul 18, 2008.
Development of an ion beam alignment system for real-time scanning tunneling microscope observation of dopant-ion irradiation
Takefumi Kamioka, Kou Sato, Yutaka Kazama, Takanobu Watanabe, and Iwao Ohdomari
An ion beam alignment system has been developed in order to realize real-time scanning tunneling microscope (STM) observation of dopant-ion irradiation that has been difficult due to the low emission intensity of the liquid-metal-ion-source (LMIS) containing dopant atoms. The alignment system is ins ... [Rev. Sci. Instrum. 79, 073707 (2008)] published Fri Jul 18, 2008.
A combined reflectometry and quartz crystal microbalance with dissipation setup for surface interaction studies
Guoliang Wang, Michael Rodahl, Malin Edvardsson, Sofia Svedhem, Gabriel Ohlsson et al.
We have developed an instrument for surface interaction studies, which combines a newly invented four detector optical reflectometry setup with quartz crystal microbalance with dissipation (QCM-D) monitoring. The design is such that data from both techniques can be obtained simultaneously on the sam ... [Rev. Sci. Instrum. 79, 075107 (2008)] published Fri Jul 18, 2008.
Development of a low-temperature photoelectron spectroscopy instrument using an electrospray ion source and a cryogenically controlled ion trap
Xue-Bin Wang and Lai-Sheng Wang
The ability to control ion temperatures is critical for gas phase spectroscopy and has been a challenge in chemical physics. A low-temperature photoelectron spectroscopy instrument has been developed for the investigation of complex anions in the gas phase, including multiply charged anions, solvate ... [Rev. Sci. Instrum. 79, 073108 (2008)] published Fri Jul 18, 2008.
Calibrating the Yule--Nielsen Modified Spectral Neugebauer Model with Ink Spreading Curves Derived from Digitized RGB Calibration Patch Images
N. P. Garg, A. K. Singla, and R. D. Hersch
The YuleNielsen modified spectral Neugebauer model (YNSN) enhanced for accounting for ink spreading in the different ink superposition conditions requires a spectrophotometer to measure the reflectances of halftone calibration patches in order to compute the ink spreading curves mapping nominal ink ... [J. Imaging Sci. Technol. 52, 040908 (2008)] published Thu Jul 17, 2008.