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1

Matsui, H., M. Nakamura, T. Mukai, K. Tsuruda i H. Hayakawa. "Observations of convection in the dayside magnetosphere by the beam instrument on Geotail". Annales Geophysicae 19, nr 3 (31.03.2001): 303–10. http://dx.doi.org/10.5194/angeo-19-303-2001.

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Abstract. We report observations of magnetospheric convection by the beam instrument, EFD-B, on Geotail. The region analyzed in this study is mainly the afternoon sector of the magnetosphere between L = 9.7 - 11.5. When the instrument is operated, electron beams are emitted from guns and some of them return to detectors attached to the main body of the satellite. However, we find that the return beams are often spread over a wide range of satellite spin phase angles, so that the calculated convection is unreliable. In order to remove noisy data, we set up suitable selection criteria. We infer that the convection strength is of the order of 20 km/s. The convection has generally westward and outward components. This indicates that the plasma located at the satellite positions is being convected toward the magnetopause. Moreover, the obtained convection is highly variable because standard deviations are comparable to the strength. We then compare the convection estimated by the beam instrument with that by the particle instrument, LEP. We find that the convections derived from the two instruments are positively correlated, with correlation coefficients above 0.7. The analysis reported here is expected to be useful in the interpretation of the multi-spacecraft data from the Cluster II mission.Key words. Magnetospheric physics (current systems; electric fields; instruments and techniques)
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2

Ehlers, Georg, Morris L. Crow, Yacouba Diawara, Franz X. Gallmeier, Xiaosong Geng, Garrett E. Granroth, Raymond D. Gregory i in. "Modern Trends in Neutron Scattering Instrument Technologies". Instruments 6, nr 3 (29.07.2022): 22. http://dx.doi.org/10.3390/instruments6030022.

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This article reviews some current trends that can be observed in the development of neutron scattering instrument technologies. While the number of neutron scattering facilities worldwide and the number of beam days they offer are largely stable, their scientific impact is increasing through improving instrumental capabilities, new and more versatile instruments, and more efficient data collection protocols. Neutron beams are becoming smaller but more intense, and instruments are being designed to utilize more ‘useful’ neutrons in unit time. This article picks and discusses a few recent developments in the areas of integrated source and instrument design, use of computational tools, new detectors, and experiment automation.
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3

Hundley, Craig R. "Beam and cylinder sound instrument". Journal of the Acoustical Society of America 77, nr 4 (kwiecień 1985): 1632. http://dx.doi.org/10.1121/1.391988.

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Cussen, L. D. "An acceptance-diagram description of beams from focusing monochromators". Journal of Applied Crystallography 35, nr 6 (13.11.2002): 702–12. http://dx.doi.org/10.1107/s0021889802015376.

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`Acceptance' diagrams are used to describe the beams produced by curved segmented (`focusing') monochromators in the kinematic approximation. This semi-analytic semi-graphical method leads to a complete description which is readily visualized in terms of instrument variables. Focusing both in and perpendicular to the scattering plane is considered. Clear relationships are identified between instrument dimensions and the beam produced. The description is directed towards neutron scattering instruments but the formalism should also apply to photons and electrons. It is demonstrated that a monochromator curved both in and perpendicular to the scattering plane (`double focused') on either a straight or curved neutron guide tube from a reactor source can produce a beam of comparable flux to that achievable at the reactor face. Such a beam has spatial dimensions comparable with modern single-crystal samples for inelastic scattering and could thus provide spectacular signal and, even more interestingly, signal to noise ratios for both elastic and inelastic single-crystal spectrometers.
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5

Giannuzzi, Lucille A. "FIB/SEM Dual Beam Instrumentation: Slicing, Dicing, Imaging, and More". Microscopy and Microanalysis 7, S2 (sierpień 2001): 796–97. http://dx.doi.org/10.1017/s1431927600030051.

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In a focused ion beam (FIB) instrument, ions (typically Ga+) obtained from a liquid metal ion source are accelerated down a column at energies up to ∽ 50 keV. The beam of ions is focused by electrostatic and octopole lens systems and the ion dose (and beam diameter) is controlled using real and/or virtual apertures. Beam sizes in FIB instruments on the order of 5-7 nm may be achieved.The versatility of the FIB instrument enables large regions of material (e.g., 500 μm3) to be removed at high beam currents in just a couple of minutes. Lower beam currents (i.e., beam diameters) are usually used to remove smaller amounts of material within the same time frame (e.g., ∽ 5μm3). The introduction of an organometallic gas in close proximity to the target allows for the deposition of metals, SiO2, and other materials, by an ion beam assisted chemical vapor deposition process.
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6

Barker, J. G., C. J. Glinka, J. J. Moyer, M. H. Kim, A. R. Drews i M. Agamalian. "Design and performance of a thermal-neutron double-crystal diffractometer for USANS at NIST". Journal of Applied Crystallography 38, nr 6 (12.11.2005): 1004–11. http://dx.doi.org/10.1107/s0021889805032103.

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An ultra-high-resolution small-angle neutron scattering (USANS) double-crystal diffractometer (DCD) is now in operation at the NIST Center for Neutron Research (NCNR). The instrument uses multiple reflections from large silicon (220) perfect single crystals, before and after the sample, to produce both high beam intensity and a low instrument background suitable for small-angle scattering measurements. The minimum detector background to beam intensity ratio (noise-to-signal, N/S) forq≥ 5 × 10−4 Å−1is 4 × 10−7. The instrument uses 2.38 Å wavelength neutrons on a dedicated thermal neutron beam port, producing a peak flux on the sample of 17300 cm−2 s−1. The typical measurement range of the instrument extends from 3 × 10−5 Å−1to 5 × 10−3 Å−1in scattering wavevector (q), providing information on material structure over the size range from 0.1 µm to 20 µm. This paper describes the design and characteristics of the instrument, the mode of operation, and presents data that demonstrate the instrument's performance.
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7

Letalick, Dietmar, i Ingmar Renhorn. "Instrument for measuring laser‐beam profiles". Review of Scientific Instruments 58, nr 5 (maj 1987): 765–67. http://dx.doi.org/10.1063/1.1139628.

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8

Nagler, Bob, Brice Arnold, Gary Bouchard, Richard F. Boyce, Richard M. Boyce, Alice Callen, Marc Campell i in. "The Matter in Extreme Conditions instrument at the Linac Coherent Light Source". Journal of Synchrotron Radiation 22, nr 3 (21.04.2015): 520–25. http://dx.doi.org/10.1107/s1600577515004865.

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The LCLS beam provides revolutionary capabilities for studying the transient behavior of matter in extreme conditions. The particular strength of the Matter in Extreme Conditions instrument is that it combines the unique LCLS beam with high-power optical laser beams, and a suite of dedicated diagnostics tailored for this field of science. In this paper an overview of the beamline, the capabilities of the instrumentation, and selected highlights of experiments and commissioning results are presented.
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9

Thomas, F. C. "Diffusion Pumps and Water Chillers". Microscopy Today 9, nr 3 (kwiecień 2001): 28–29. http://dx.doi.org/10.1017/s1551929500056947.

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This note concerns two very important parts of most beam instrument systems; diffusion pumps and water chillers. As we'll see below, the two can be intimately connected.Many SEMs, TEMs and other electron beam instruments contain one or more diffusion pumps as part of their vacuum systems. These are usually vertically-oriented cylindrical objects, perhaps 30 cm high, wrapped in several turns of copper tubing. They are usually placed behind or below the instrument's column, and typically handle high vacuums for tungsten filaments, or backing for ion pumps with other emitter types. Generally, these units are fairly maintenance-free; a change of oil every few years may be all that is required.
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10

Popova, I. I., i F. X. Gallmeier. "Shielding development for the VENUS imaging instrument". Journal of Neutron Research 22, nr 2-3 (20.10.2020): 131–38. http://dx.doi.org/10.3233/jnr-200164.

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VENUS is an imaging instrument that will use a broad range of neutron wavelengths, from epithermal to cold, will include enhanced contrast mechanisms, and will offer novel energy-selective imaging techniques that directly connect the structures, properties, and function of complex engineering materials and systems to reveal practical and fundamental answers about their real-world performance. The instrument is to be built at SNS beam line 10 and will face the decoupled poisoned hydrogen moderator. The driving cost for the instrument is the beam line and instrument cave shielding. Initial scoping analyses were performed to estimate thickness and composition of shielding materials for the instrument cave and beam line. In light of the upcoming Proton Power Upgrade (PPU) project, these transport analyses were performed for proton beam on target at 1.3 GeV and 2 MW.
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11

Krivanek, Ondrej L., Jan Rusz, Juan-Carlos Idrobo, Tracy J. Lovejoy i Niklas Dellby. "Toward Single Mode, Atomic Size Electron Vortex Beams". Microscopy and Microanalysis 20, nr 3 (7.05.2014): 832–36. http://dx.doi.org/10.1017/s143192761400083x.

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AbstractWe propose a practical method of producing a single mode electron vortex beam suitable for use in a scanning transmission electron microscope (STEM). The method involves using a holographic “fork” aperture to produce a row of beams of different orbital angular momenta, as is now well established, magnifying the row so that neighboring beams are separated by about 1 µm, selecting the desired beam with a narrow slit, and demagnifying the selected beam down to 1–2 Å in size. We show that the method can be implemented by adding two condenser lenses plus a selection slit to a straight-column cold-field emission STEM. It can also be carried out in an existing instrument, the monochromated Nion high-energy-resolution monochromated electron energy-loss spectroscopy-STEM, by using its monochromator in a novel way. We estimate that atom-sized vortex beams with ≥20 pA of current should be attainable at 100–200 keV in either instrument.
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12

Pollard, James E. "Beam‐centroid tracking instrument for ion thrusters". Review of Scientific Instruments 65, nr 12 (grudzień 1994): 3733–38. http://dx.doi.org/10.1063/1.1144499.

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13

Paschmann, G., M. Boehm, H. H�fner, R. Frenzel, P. Parigger, F. Melzner, G. Haerendel, C. A. Kletzing, R. B. Torbert i G. Sartori. "The Electron Beam Instrument (F6) on Freja". Space Science Reviews 70, nr 3-4 (listopad 1994): 447–63. http://dx.doi.org/10.1007/bf00756881.

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14

Suryati, Suryati, i Tri Wahyu Widodo. "SIGHT SINGING SEBAGAI STRATEGI PEMBELAJARAN INSTRUMEN PIANO DI PRODI PENDIDIKAN MUSIK ISI YOGYAKARTA". Resital: Jurnal Seni Pertunjukan 21, nr 2 (1.06.2021): 99–112. http://dx.doi.org/10.24821/resital.v21i2.3379.

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Sight Singing is the ability to read the notation and immediately sing the tune in accordance with the melody on the sheet music. Sight Singing is the activity of singing with solmisasi or movabel "do". This study aims to improve the ability to read beam notation in learning mandatory piano instruments using the Sight Singing approach. The Mandatory Piano Instrument course is one of the practical courses that must be taken by all Music Education Study Program students, ISI Yogyakarta. Not all new students in Music Education Study Program can read the beam notation, so this Piano Compulsory Instrument course course is always feared by students who have not read fluent notation. Sight singing as a strategy to enhance the learning of Piano Mandatory Instruments. This research is focused on the application of Sight singing in learning Mandatory Piano Instruments in Music Education Study Program. This research uses Classroom Action Research which can be categorized as a qualitative-experimental research by applying the Sight singing method. The results of this study are the learning process of the Mandatory Piano Instrument with the application of the Sight singing method more effectively to improve the ability to learn to read notation while playing the Piano Instrument, and students can be more expressing, impressed singing by accompanying themselves.
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15

Polonsky, Igor N., Steven P. Love i Anthony B. Davis. "Wide-Angle Imaging Lidar Deployment at the ARM Southern Great Plains Site: Intercomparison of Cloud Property Retrievals". Journal of Atmospheric and Oceanic Technology 22, nr 6 (1.06.2005): 628–48. http://dx.doi.org/10.1175/jtech1741.1.

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Abstract The Wide-Angle Imaging Lidar (WAIL), a new instrument that measures cloud optical and geometrical properties by means of off-beam lidar returns, was deployed as part of a multi-instrument campaign to probe a cloud field at the Atmospheric Radiation Measurement (ARM) Southern Great Plain (SGP) site on 25 March 2002. WAIL is designed to determine physical and geometrical characteristics using the off-beam component of the lidar return that can be adequately modeled within the diffusion approximation. Using WAIL data, the extinction coefficient and geometrical thickness of a dense cloud layer is estimated, from which optical thickness is inferred. Results from the new methodology agree well with counterparts obtained from other instruments located permanently at the SGP ARM site and from the WAIL-like airborne instrument that flew over the site during our observation period.
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16

Volkert, C. A., i A. M. Minor. "Focused Ion Beam Microscopy and Micromachining". MRS Bulletin 32, nr 5 (maj 2007): 389–99. http://dx.doi.org/10.1557/mrs2007.62.

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AbstractThe fairly recent availability of commercial focused ion beam (FIB) microscopes has led to rapid development of their applications for materials science. FIB instruments have both imaging and micromachining capabilities at the nanometer–micrometer scale; thus, a broad range of fundamental studies and technological applications have been enhanced or made possible with FIB technology. This introductory article covers the basic FIB instrument and the fundamentals of ion–solid interactions that lead to the many unique FIB capabilities as well as some of the unwanted artifacts associated with FIB instruments. The four topical articles following this introduction give overviews of specific applications of the FIB in materials science, focusing on its particular strengths as a tool for characterization and transmission electron microscopy sample preparation, as well as its potential for ion beam fabrication and prototyping.
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17

Alhamd, M. W., Aqeel Maryoosh Jary, Sadeq Naeem Atiyah i Nazar Ali Abbood. "Improve X-ray images using quality assurance tests". Journal of Physics: Conference Series 2114, nr 1 (1.12.2021): 012034. http://dx.doi.org/10.1088/1742-6596/2114/1/012034.

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Abstract In this research, entrance surface doses of patients which are resulted from a classical radiograph in most widespread tests (Chest, skull, abdomen, limbs, …) have been measured with selected instruments in (Specialized surgeries hospital) and one of the private clinic in Baghdad, the instruments are of various origins and different make date. A group of patients (10 patients) for each test and according the average of the resulted doses. Comparison of the patient’s doses, in this research, has been close with the reliable International standards and it has been found that radiological doses are bigger than reference doses ranging (132–1.79) in most of the appliance and the range doses to one whenever the instrument is new and the radiographer has good experience, this increase relates to several functions discussed in the research in detail For the importance of the quality assurance of x-ray instruments, three tests have been performed by three of the instruments only, and these tests are : Beam Alignment test : The Beam Alignment was measured and the x-ray radiograph was found symmetrical round the two axes of the instruments (A, B) but it is about 3 ° away from the vertical axis of the instrument (C). Optical and Radiation Field Congruence Test: The light field coincides with the radiative field in a and b and their mismatch in c. Focal Spot Size Test: The radiation focus area was measured by the star tool and what appeared is that the focus of the x-ray instrument (C) is smaller than the international standards on the contrary of the focus area of the x-ray instrument (E) which is identical with the international standards. From these results reached is that the instruments (A, B) have passed quality assurance tests and they are suitable for work in the present, but the instrument (C) has not passed most of the quality assurance tests, so this instrument should not be used for medical tests This in research is considered the first one for these instruments to evaluate their doses or measure a quality assurance.
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18

Fetherolf, B. L., T. A. Litzinger i K. K. Kuo. "An instrument for measuring high‐power laser beam profiles and beam attenuation". Review of Scientific Instruments 61, nr 1 (styczeń 1990): 7–10. http://dx.doi.org/10.1063/1.1141904.

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19

Baryshev, S. V., N. G. Becker, A. V. Zinovev, C. E. Tripa i I. V. Veryovkin. "Dual-beam versus single-beam depth profiling: Same sample in same instrument". Rapid Communications in Mass Spectrometry 27, nr 24 (11.11.2013): 2828–32. http://dx.doi.org/10.1002/rcm.6749.

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Cash, Jennifer N., Sarah Kearns, Yilai Li i Michael A. Cianfrocco. "High-resolution cryo-EM using beam-image shift at 200 keV". IUCrJ 7, nr 6 (29.10.2020): 1179–87. http://dx.doi.org/10.1107/s2052252520013482.

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Recent advances in single-particle cryo-electron microscopy (cryo-EM) data collection utilize beam-image shift to improve throughput. Despite implementation on 300 keV cryo-EM instruments, it remains unknown how well beam-image-shift data collection affects data quality on 200 keV instruments and the extent to which aberrations can be computationally corrected. To test this, a cryo-EM data set for aldolase was collected at 200 keV using beam-image shift and analyzed. This analysis shows that the instrument beam tilt and particle motion initially limited the resolution to 4.9 Å. After particle polishing and iterative rounds of aberration correction in RELION, a 2.8 Å resolution structure could be obtained. This analysis demonstrates that software correction of microscope aberrations can provide a significant improvement in resolution at 200 keV.
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21

Reinhard, Christina, Michael Drakopoulos, Sharif I. Ahmed, Hans Deyhle, Andrew James, Christopher M. Charlesworth, Martin Burt i in. "Beamline K11 DIAD: a new instrument for dual imaging and diffraction at Diamond Light Source". Journal of Synchrotron Radiation 28, nr 6 (22.10.2021): 1985–95. http://dx.doi.org/10.1107/s1600577521009875.

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The Dual Imaging and Diffraction (DIAD) beamline at Diamond Light Source is a new dual-beam instrument for full-field imaging/tomography and powder diffraction. This instrument provides the user community with the capability to dynamically image 2D and 3D complex structures and perform phase identification and/or strain mapping using micro-diffraction. The aim is to enable in situ and in operando experiments that require spatially correlated results from both techniques, by providing measurements from the same specimen location quasi-simultaneously. Using an unusual optical layout, DIAD has two independent beams originating from one source that operate in the medium energy range (7–38 keV) and are combined at one sample position. Here, either radiography or tomography can be performed using monochromatic or pink beam, with a 1.4 mm × 1.2 mm field of view and a feature resolution of 1.2 µm. Micro-diffraction is possible with a variable beam size between 13 µm × 4 µm and 50 µm × 50 µm. One key functionality of the beamline is image-guided diffraction, a setup in which the micro-diffraction beam can be scanned over the complete area of the imaging field-of-view. This moving beam setup enables the collection of location-specific information about the phase composition and/or strains at any given position within the image/tomography field of view. The dual beam design allows fast switching between imaging and diffraction mode without the need of complicated and time-consuming mode switches. Real-time selection of areas of interest for diffraction measurements as well as the simultaneous collection of both imaging and diffraction data of (irreversible) in situ and in operando experiments are possible.
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22

Sporea, Dan, Andrei Stăncălie, Nicu Becherescu, Martin Becker i Manfred Rothhardt. "An Electron Beam Profile Instrument Based on FBGs". Sensors 14, nr 9 (25.08.2014): 15786–801. http://dx.doi.org/10.3390/s140915786.

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23

Paschmann, G., J. M. Quinn, R. B. Torbert, H. Vaith, C. E. McIlwain, G. Haerendel, O. H. Bauer i in. "The Electron Drift Instrument on Cluster: overview of first results". Annales Geophysicae 19, nr 10/12 (30.09.2001): 1273–88. http://dx.doi.org/10.5194/angeo-19-1273-2001.

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Abstract. EDI measures the drift velocity of artificially injected electron beams. From this drift velocity, the perpendicular electric field and the local magnetic field gradients can be deduced when employing different electron energies. The technique requires the injection of two electron beams at right angles to the magnetic field and the search for those directions within the plane that return the beams to their associated detectors after one or more gyrations. The drift velocity is then derived from the directions of the two beams and/or from the difference in their times-of-flight, measured via amplitude-modulation and coding of the emitted electron beams and correlation with the signal from the returning electrons. After careful adjustment of the control parameters, the beam recognition algorithms, and the onboard magnetometer calibrations during the commissioning phase, EDI is providing excellent data over a wide range of conditions. In this paper, we present first results in a variety of regions ranging from the polar cap, across the magnetopause, and well into the magnetosheath.Key words. Electron drift velocity (electric fields; plasma convection; instruments and techniques)
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Verniero, J. L., B. D. G. Chandran, D. E. Larson, K. Paulson, B. L. Alterman, S. Badman, S. D. Bale i in. "Strong Perpendicular Velocity-space Diffusion in Proton Beams Observed by Parker Solar Probe". Astrophysical Journal 924, nr 2 (1.01.2022): 112. http://dx.doi.org/10.3847/1538-4357/ac36d5.

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Abstract The SWEAP instrument suite on Parker Solar Probe (PSP) has detected numerous proton beams associated with coherent, circularly polarized, ion-scale waves observed by PSP’s FIELDS instrument suite. Measurements during PSP Encounters 4−8 revealed pronounced complex shapes in the proton velocity distribution functions (VDFs), in which the tip of the beam undergoes strong perpendicular diffusion, resulting in VDF level contours that resemble a “hammerhead.” We refer to these proton beams, with their attendant “hammerhead” features, as the ion strahl. We present an example of these observations occurring simultaneously with a 7 hr ion-scale wave storm and show results from a preliminary attempt at quantifying the occurrence of ion-strahl broadening through three-component ion VDF fitting. We also provide a possible explanation of the ion perpendicular scattering based on quasilinear theory and the resonant scattering of beam ions by parallel-propagating, right circularly polarized, fast magnetosonic/whistler waves.
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Berujon, Sebastien, Eric Ziegler i Peter Cloetens. "X-ray pulse wavefront metrology using speckle tracking". Journal of Synchrotron Radiation 22, nr 4 (9.05.2015): 886–94. http://dx.doi.org/10.1107/s1600577515005433.

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An instrument allowing the quantitative analysis of X-ray pulsed wavefronts is presented and its processing method explained. The system relies on the X-ray speckle tracking principle to accurately measure the phase gradient of the X-ray beam from which beam optical aberrations can be deduced. The key component of this instrument, a semi-transparent scintillator emitting visible light while transmitting X-rays, allows simultaneous recording of two speckle images at two different propagation distances from the X-ray source. The speckle tracking procedure for a reference-less metrology mode is described with a detailed account on the advanced processing schemes used. A method to characterize and compensate for the imaging detector distortion, whose principle is also based on speckle, is included. The presented instrument is expected to find interest at synchrotrons and at the new X-ray free-electron laser sources under development worldwide where successful exploitation of beams relies on the availability of an accurate wavefront metrology.
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Bloomer, C., M. E. Newton, G. Rehm i P. S. Salter. "A single-crystal diamond X-ray pixel detector with embedded graphitic electrodes". Journal of Synchrotron Radiation 27, nr 3 (31.03.2020): 599–607. http://dx.doi.org/10.1107/s160057752000140x.

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The first experimental results from a new transmissive diagnostic instrument for synchrotron X-ray beamlines are presented. The instrument utilizes a single-crystal chemical-vapour-deposition diamond plate as the detector material, with graphitic wires embedded within the bulk diamond acting as electrodes. The resulting instrument is an all-carbon transmissive X-ray imaging detector. Within the instrument's transmissive aperture there is no surface metallization that could absorb X-rays, and no surface structures that could be damaged by exposure to synchrotron X-ray beams. The graphitic electrodes are fabricated in situ within the bulk diamond using a laser-writing technique. Two separate arrays of parallel graphitic wires are fabricated, running parallel to the diamond surface and perpendicular to each other, at two different depths within the diamond. One array of wires has a modulated bias voltage applied; the perpendicular array is a series of readout electrodes. X-rays passing through the detector generate charge carriers within the bulk diamond through photoionization, and these charge carriers travel to the nearest readout electrode under the influence of the modulated electrical bias. Each of the crossing points between perpendicular wires acts as an individual pixel. The simultaneous read-out of all pixels is achieved using a lock-in technique. The parallel wires within each array are separated by 50 µm, determining the pixel pitch. Readout is obtained at 100 Hz, and the resolution of the X-ray beam position measurement is 600 nm for a 180 µm size beam.
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Matsui, I., T. Katsuta, T. Kawasaki, S. Hayashi, T. Furutsu, T. Onai, K. Myochin i in. "Development of a 1MV-Field-Emission Electron Microscope I. Instrument". Microscopy and Microanalysis 6, S2 (sierpień 2000): 1138–39. http://dx.doi.org/10.1017/s1431927600038186.

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We have developed 100-kV, 200-kV, and 350-kV cold-field-emission transmission electron microscopes (FE-TEMs) successively up to this time. Using these instruments, we have been studying the magnetic structure of materials, high-resolution imaging by electron holography, and dynamic observation of the vortex in superconductors by Lorentz microscopy. To make more progress in our research, we need a better electron beam in terms of coherency, beam brightness, and penetration. Here, we report a new lMV-cold-field-emission transmission electron microscope we have developed. Historically, the pioneering projects on a lMV-field-emission scanning transmission electron microscope (FE-STEM) (Zeitler and Crewe, 1974) and a 1.6MV FE-STEM (Jouffrey et al., 1984) have been reported. In 1988, Maruse and Shimoyama obtained a lMV-field-emission beam using their 1.25MV-STEM connected to a field-emission gun. Since then, continuous improvements in beam brightness has been made.The target specifications of our 1 MV-cold-field-emission TEM (H-1000FT) are as follows: Acceleration voltage: 1MV, high-voltage stability :
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Visser, Bradley, Jannis Röhrbein, Peter Steigmeier, Luka Drinovec, Griša Močnik i Ernest Weingartner. "A single-beam photothermal interferometer for in situ measurements of aerosol light absorption". Atmospheric Measurement Techniques 13, nr 12 (23.12.2020): 7097–111. http://dx.doi.org/10.5194/amt-13-7097-2020.

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Abstract. We have developed a novel single-beam photothermal interferometer and present here its application for the measurement of aerosol light absorption. The use of only a single laser beam allows for a compact optical set-up and significantly easier alignment compared to standard dual-beam photothermal interferometers, making it ideal for field measurements. Due to a unique configuration of the reference interferometer arm, light absorption by aerosols can be determined directly – even in the presence of light-absorbing gases. The instrument can be calibrated directly with light-absorbing gases, such as NO2, and can be used to calibrate other light absorption instruments. The detection limits (1σ) for absorption for 10 and 60 s averaging times were determined to be 14.6 and 7.4 Mm−1, respectively, which for a mass absorption cross section of 10 m2 g−1 leads to equivalent black carbon concentration detection limits of 1460 and 740 ng m−3, respectively. The detection limit could be reduced further by improvements to the isolation of the instrument and the signal detection and processing schemes employed.
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Holt, R. A. "A Comprehensive Approach to in Situ Stress Measurement". Advances in X-ray Analysis 29 (1985): 29–35. http://dx.doi.org/10.1154/s0376030800010089.

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Recent developments in position sensitive detectors (PSD's), solid state power and computer technologies make it possible to design accurate instruments for in-situ stress measurement. Such instruments require compromises in the interests of portability, size and speed stiich may limit accuracy and/or versatility. Furthermore, extraction of a stress tensor from X-ray data is not always straightforward and considerable research is required before an instrument for X-ray stress measurement can be treated as a “black box” to be given to an uneducated operator.The development of a new instrument for in-situ stress measurement is described in this paper. It was conceived as a field instrument with two position-sensitive proportional counters (PSPC's) for use in the single exposure mode (SET), and incorporates precise angular qontrol of the incident X-ray beam and data analysis to eliminate irregular Bragg peaks owing to coarse grain structure, An experimental instrument was built tc test the concept (1).
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30

Andersen, Ken Holst, Mads Bertelsen, Luca Zanini, Esben Bryndt Klinkby, Troels Schönfeldt, Phillip Martin Bentley i Jan Saroun. "Optimization of moderators and beam extraction at the ESS". Journal of Applied Crystallography 51, nr 2 (12.03.2018): 264–81. http://dx.doi.org/10.1107/s1600576718002406.

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A global approach coupling the moderator to the beam extraction system has been applied for the design optimization of the thermal and cold moderators of the European Spallation Source (ESS), which will be the brightest neutron source in the world for condensed-matter studies. The design is based on the recently developed high-brightness low-dimensional moderator concepts.Para-hydrogen is used for the cold neutron source, while thermal neutrons are provided by moderation in water. The overall moderation configuration was chosen in order to satisfy a range of requirements on bispectral extraction, beamport configuration and instrument performance. All instruments are served by a single moderator assembly above the target, arranged in a `butterfly' geometry with a height of 3 cm. This was determined to be the optimal height for trade-off between high brightness and efficient guide illumination, by analysis of the performance of 23 instruments, based on the reference suite of the ESS Technical Design Report. The concept of `brilliance transfer' is introduced to quantify the performance of the neutron optical system from the source to the sample. The target monolith incorporates a grid of 42 neutron beamports with an average separation of 6°, allowing a free choice between cold and thermal neutron sources at all instrument positions. With the large number of beamports and the space below the target available for future moderators, ample opportunities are available for future upgrades.
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31

Danilatos, Gerasimos D. "Radiofrequency Gaseous Detection Device". Microscopy and Microanalysis 6, nr 1 (styczeń 2000): 12–20. http://dx.doi.org/10.1017/s1431927600000027.

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A radiofrequency gaseous detection device is proposed for use with instruments employing charged particle beams, such as electron microscopes and ion beam technologies, as well as for detection of ionizing radiations as in proportional counters. An alternating (oscillating) electromagnetic field in the radiofrequency range is applied in a gaseous environment of the instrument. Both the frequency and amplitude of oscillation are adjustable. The electron or ion beam interacts with a specimen and releases free electrons in the gas. Similarly, an ionizing radiation source releases free electrons in the gas. The free electrons are acted upon by the alternating electromagnetic field and undergo an oscillatory motion resulting in multiple collisions with the gas molecules, or atoms. At sufficiently low pressures, the oscillating electrons also collide with surrounding walls. These processes result in an amplified electron signal and an amplified photon signal in a controlled discharge. The amplified signals, which are proportional to the initial number of free electrons, are collected by suitable means for further processing and analysis.
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32

Smiljanic, I., I. Bozovic Jelisavcic, G. Kacarevic, N. Vukasinovic, I. Vidakovic i V. Rekovic. "Systematic uncertainties in integrated luminosity measurement at CEPC". Journal of Instrumentation 17, nr 09 (1.09.2022): P09014. http://dx.doi.org/10.1088/1748-0221/17/09/p09014.

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Abstract The very forward region is one of the most challenging regions to instrument at a future e + e - collider. At CEPC, machine-detector interface includes, among others, a calorimeter dedicated for precision measurement of the integrated luminosity at a per mill level or better. Here we review a feasibility of such precision, from the point of view of systematic effects arising from luminometer mechanical precision and positioning, beam-related requirements and physics background from two-photon processes. The impact of the beam energy spread and its uncertainty on the integrated luminosity precision is also discussed, as well as the achievable beam energy spread precision with the post-CDR CEPC beams.
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33

Smiljanic, I., I. Bozovic Jelisavcic, G. Kacarevic, N. Vukasinovic, I. Vidakovic i V. Rekovic. "Erratum: Systematic uncertainties in integrated luminosity measurement at CEPC". Journal of Instrumentation 17, nr 12 (1.12.2022): E12001. http://dx.doi.org/10.1088/1748-0221/17/12/e12001.

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Abstract The very forward region is one of the most challenging regions to instrument at a future e+e− collider. At CEPC, machine-detector interface includes, among others, a calorimeter dedicated for precision measurement of the integrated luminosity at a per mill level or better. Here we review a feasibility of such precision, from the point of view of systematic effects arising from luminometer mechanical precision and positioning, beam-related requirements and physics background from two-photon processes. The impact of the beam energy spread and its uncertainty on the integrated luminosity precision is also discussed, as well as the achievable beam energy spread precision with the post-CDR CEPC beams.
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34

Kachatkou, Anton, Nicholas Kyele, Peter Scott i Roelof van Silfhout. "In situX-ray beam imaging using an off-axis magnifying coded aperture camera system". Journal of Synchrotron Radiation 20, nr 4 (18.05.2013): 596–602. http://dx.doi.org/10.1107/s0909049513011060.

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An imaging model and an image reconstruction algorithm for a transparent X-ray beam imaging and position measuring instrument are presented. The instrument relies on a coded aperture camera to record magnified images of the footprint of the incident beam on a thin foil placed in the beam at an oblique angle. The imaging model represents the instrument as a linear system whose impulse response takes into account the image blur owing to the finite thickness of the foil, the shape and size of camera's aperture and detector's point-spread function. The image reconstruction algorithm first removes the image blur using the modelled impulse response function and then corrects for geometrical distortions caused by the foil tilt. The performance of the image reconstruction algorithm was tested in experiments at synchrotron radiation beamlines. The results show that the proposed imaging system produces images of the X-ray beam cross section with a quality comparable with images obtained using X-ray cameras that are exposed to the direct beam.
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35

Postek, Michael T. "Calibration of Electron Microscopes: How to do this, how often, pit-falls and problems". Microscopy Today 10, nr 5 (wrzesień 2002): 26–30. http://dx.doi.org/10.1017/s1551929500058338.

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SEM Instrument calibration is something most people don't always realize they need to do. Images look about right so the magnification seems close enough. Today, measurements are being done in specialized scanned beam metrology instruments everyday, so correct magnification calibration is very important. Calibration is probably more acknowledged from the point of the transmission electron microscope than for the scanning microscope. But, it still needs to be done. Today, people can buy SEM's that cost around $100,000 (refurbished ones somewhat less) to $2.5M with one instrument model from one manufacturer costing about $8M. Believe it or not, often the instrument buyer thinks that as soon as they get the instrument into their facility (since it is new and they paid a lot of money for it) that it is perfect and everything is correct.
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36

Marraccini, Philip J., i Nabeel A. Riza. "Multimode laser beam analyzer instrument using electrically programmable optics". Review of Scientific Instruments 82, nr 12 (grudzień 2011): 123107. http://dx.doi.org/10.1063/1.3669535.

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37

Wurzer, Helmut, Rainer Mäckel, Jürgen Lademann, Hans-Jürgen Weigmann, Heike Audring i Hans-Dieter Ließ. "Aerosol-Beam-Koagulator – Ein neues Instrument zur kontaktlosen Softkoagulation". Biomedizinische Technik/Biomedical Engineering 42, s2 (1997): 354–55. http://dx.doi.org/10.1515/bmte.1997.42.s2.354.

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38

Pureti, R., B. Douhard, D. Joris, A. Merkulov i W. Vandervorst. "Cesium/Xenon dual beam sputtering in a Cameca instrument". Surface and Interface Analysis 46, S1 (22.09.2014): 25–30. http://dx.doi.org/10.1002/sia.5658.

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39

Matsuo, Masaru, i Yuezhen Bin. "Education program for controversial defect of recent X-ray instrument termed as a simultaneous small angle X-ray scattering and wide angle X-ray diffraction measuring instrument". Pure and Applied Chemistry 90, nr 6 (27.06.2018): 969–87. http://dx.doi.org/10.1515/pac-2017-0801.

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Abstract Simultaneous rotations of sample and X-ray detected counter are needed to evaluate orientation distribution of crystallites and amorphous chains oriented predominantly parallel to the film surface in addition to exact diffraction peak profiles obtained without the complicated intensity corrections. The rotation mode is known as “θ–2θ scanning” system (θ: film, 2θ: counter). The system has been mainly used in research and development institutes. However, such instruments are not produced at present. Recently, small angle X-ray scattering (SAXS) and wide angle X-ray diffraction (WAXD) intensities have been measured by using X-ray beam generated along one direction. The brand name of the instrument is “a simultaneous SAXS and WAXD measuring instrument”. The X-ray beam generated by the instrument has surely high luminance providing high degree resolution of peak profiles by diffraction and/or scattering. The sample stage and detector, however, are fixed, since the intensities for SAXS and WAXD are obtained by the digital display of the number of X-ray photons detected on the imaging plate. Such optical system contains controversial defect on evaluating orientation of crystal planes parallel to the surface of films prepared by T-die and inflation methods as well as the exact profile. The imaging plate cannot detect the diffraction intensity from the crystal planes existing in the angle range between incident beam and Bragg angle associated with the diffraction peak position of the individual crystal planes.
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40

Dewhurst, C. D. "Novel multiple-beam very small angle neutron scattering (VSANS) using a conventional SANS instrument". Journal of Applied Crystallography 47, nr 4 (14.06.2014): 1180–89. http://dx.doi.org/10.1107/s1600576714012801.

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This article demonstrates how a small-angle neutron scattering (SANS) instrument, such as D33 at the Institut Laue–Langevin, can be configured without extensive modification to produce multiple highly collimated beams for measurements at the smallest scattering angles. This extends the range of material length scales able to be studied to greater than 1 µm, almost one order of magnitude greater than that of a conventional SANS instrument. The multiple-beam configuration uses the intrinsic properties of the neutron guide system and source and sample apertures with no additional optical devices or precise aperture array alignments. Up to several hundred individual beams, separated in angle by fractions of a degree in both the horizontal and vertical directions, can be extracted, which focus at the sample and diverge towards the distant neutron detector. This is particularly useful for the study of small samples, which can be probed at the smallest scattering angles while retaining sufficient neutron flux because of the use of multiple beams. The resulting data on the area neutron detector consist of multiple scattering or diffraction images which extend over and overlap those produced by neighboring beams. While the principle of the technique is rather simple, analysis of the overlapping SANS patterns requires the development of software techniques to extract the single scattering function.
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41

Lyngh, D., N. de la Cour, L. Åström, J. Koning, B. Jönsson, S. Ghatnekar Nilsson, C. Hall i in. "Engineering and prototyping of ESS neutron beam extraction system". Journal of Neutron Research 22, nr 2-3 (20.10.2020): 109–18. http://dx.doi.org/10.3233/jnr-200155.

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In the development of the European Spallation Source, the engineering phase of the Neutron Beam Extraction System is approaching its end. Currently, prototyping is ongoing to verify and increase the understanding of the manufacturing limitations in relation to the engineering aspects and beam extraction requirements from the instruments. After that the manufacturing of the suite of 16 neutron beam port inserts (NBPI) and light shutter systems (LSS) are phased into final detail design and manufacturing. The NBPIs have been developed as a close collaboration between ESS’ instruments design coordinators and intricately integrate a set of copper optics within a controlled atmosphere within the target monolith pressure vessel. The NBPIs therefore includes not only a processed atmosphere but also enables fine alignment of the optics assemblies within it, but also includes a system for inserting it into a very precisely aligned and measured position. Outside the NBPIs, along the neutron beam paths, sits the Neutron Beam Windows and sequentially, the LSS which incorporates an optical bridge beam guide before the beam enters the bunker area and the individual instrument beam transports. ESS have chosen the concept of LSS, which generates demanding requirements for alignment of moving shutter parts. These system parts are placed in the bunker area and bunker basement, areas that are partly accessible during maintenance periods.
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42

Torkar, K., H. Arends, W. Baumjohann, C. P. Escoubet, A. Fazakerley, M. Fehringer, G. Fremuth i in. "Spacecraft potential control for Double Star". Annales Geophysicae 23, nr 8 (8.11.2005): 2813–23. http://dx.doi.org/10.5194/angeo-23-2813-2005.

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Abstract. The spacecraft potential of Double Star TC-1 is positive in large parts of the orbits due to the photo-effect from solar EUV irradiation. These positive potentials typically disturb low energy plasma measurements on board. The potential can be reduced, and thereby the particle measurements improved, by emitting a positive ion beam. This method has successfully been applied on several other spacecraft and it has also been chosen for TC-1. The instrument TC-1/ASPOC is a derivative of the Cluster/ASPOC instruments, from which it has inherited many features. The paper describes the adaptations and further developments made for the ion emitters and the electronics. The instrument performs very well and can support higher beam currents than on Cluster. The expected significant improvement of the low energy particle measurements on board was indeed observed. The modifications of the electron distributions are analysed for a one-time interval when the spacecraft was located in the magnetosheath. The change in the potential due to the ion beam was determined, and first studies of the 3-D electron distributions in response to the spacecraft potential control have been performed, which indicate that the method works as expected.
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43

Steinmeyer, P. A. "Special Application of the Debye Microdiffractometer". Advances in X-ray Analysis 29 (1985): 251–56. http://dx.doi.org/10.1154/s0376030800010338.

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The Debye microdiffractometer, a recently developed instrument, enables diffraction patterns to be obtained from very small samples or from selected areas of samples. The instrument discussed here, a Rigaku Model 2870E1 microdiffractometer, features an annular sealed proportional counter which is moved along the primary beam axis for two theta scanning, as seen in Figure 1, This configuration allows most of a Debye cone to be detected, making the use of a primary bean typically less than 100 microns in diameter practical. An integral microscope facilitates sample positioning for diffraction from selected areas of a specimen. The capability of the Instrument is apparent from the diffractometer traces of Figure 2, in which intermetallie compounds in a braze joint are identified.
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44

Zhang, Lei, i Zhi Yong Hao. "Model Analysis and Optimization Design for Mg-Based Instrument Panel Beam Assembly". Advanced Materials Research 681 (kwiecień 2013): 204–8. http://dx.doi.org/10.4028/www.scientific.net/amr.681.204.

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Based on the basic structure in the practical installation condition, the static model of the instrument panel (IP) beam assembly is developed. To reduce the weight, Mg is substituted for steel as the material of the structure. The finite element software is used to evaluate the constraint modal performance, rigidness and strength withstanding the specific load. After the comparison of model analysis with different materials, the Mg-based IP beam assembly is optimized to achieve the performance the steel-based one has. The process offers the reference to the lightweight design of Mg-based IP beam assembly.
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45

BOUFFARD, FRANÇOIS, i JEAN-MARC THÉRIAULT. "BACKGROUND CONTRIBUTIONS IN DIRECT AND DIFFERENTIAL FOURIER TRANSFORM LWIR MEASUREMENTS: A COMPARATIVE ANALYSIS". International Journal of High Speed Electronics and Systems 18, nr 02 (czerwiec 2008): 263–75. http://dx.doi.org/10.1142/s0129156408005333.

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In order to assess the differences between background clutter using the CATSI instrument in direct (single-beam) and differential (double-beam) mode, a survey of background measurements was undertaken. Measurements include samples of sky, mountains, forest, buildings, roads and snow during springtime in the long wave infrared using both single-beam and double-beam interferometry. It is found that background distribution and statistics in these two modes are significantly different, with the differential mode presenting less variation than the direct mode. This may impact the ability to detect atmospheric contaminants. This analysis was performed in order to better understand the difference between operating a standard and a differential FTIR instrument.
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46

Markó, Gergely, Péter Primusz i József Péterfalvi. "Measuring the Bearing Capacity of Forest Roads with an Improved Benkelman Beam Apparatus". Acta Silvatica et Lignaria Hungarica 9, nr 1 (1.12.2013): 97–109. http://dx.doi.org/10.2478/aslh-2013-0008.

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Abstract Bearing capacity measurements of roads were traditionally carried out using the Benkelman beam. The Benkelman beam measurements provide the maximum vertical deflection of the pavement under 50 kN of wheel load. Nowadays the bearing capacity of public roads is measured with falling weight deflectometers. Falling weight deflectometer measurements provide the full deflection basin. It is convenient to use these high precision instruments on forest roads, but their application is inefficient and costly. The Department of Forest Opening Up developed a new method to measure the full deflection basin with the Benkelman beam. Besides the instrument improvement the authors developed a new method for the processing of the deflection basin data. Results are presented through the case study of a 2nd class opening up forest road.
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47

Danilatos, Gerasimos D., Matthew R. Phillips i John V. Nailon. "Electron Beam Current Loss at the High-Vacuum– High-Pressure Boundary in the Environmental Scanning Electron Microscope". Microscopy and Microanalysis 7, nr 5 (wrzesień 2001): 397–406. http://dx.doi.org/10.1007/s10005-001-0008-0.

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AbstractA significant loss in electron probe current can occur before the electron beam enters the specimen chamber of an environmental scanning electron microscope (ESEM). This loss results from electron scattering in a gaseous jet formed inside and downstream (above) the pressure-limiting aperture (PLA), which separates the high-pressure and high-vacuum regions of the microscope. The electron beam loss above the PLA has been calculated for three different ESEMs, each with a different PLA geometry: an ElectroScan E3, a Philips XL30 ESEM, and a prototype instrument. The mass thickness of gas above the PLA in each case has been determined by Monte Carlo simulation of the gas density variation in the gas jet. It has been found that the PLA configurations used in the commercial instruments produce considerable loss in the electron probe current that dramatically degrades their performance at high chamber pressure and low accelerating voltage. These detrimental effects are minimized in the prototype instrument, which has an optimized thin-foil PLA design.
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48

Furusaka, M., S. Takeda, A. Homma, F. Fujita, T. Miyata, Y. Kiyanagi i M. Ohnuma. "Multi-Incident Beam Compact Time-Of-Flight SANS Instrument with 1 Millimeter Diameter beams". Journal of Physics: Conference Series 340 (8.02.2012): 012027. http://dx.doi.org/10.1088/1742-6596/340/1/012027.

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49

Saif, M. T. A., i N. C. MacDonald. "Microinstruments for submicron material studies". Journal of Materials Research 13, nr 12 (grudzień 1998): 3353–56. http://dx.doi.org/10.1557/jmr.1998.0454.

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We present two microinstruments for submicron scale material characterization. One of the instruments applies torsion on two single crystal silicon bars with square cross sections,1 and 2.25 μm2, until fracture. The maximum shear stress prior to fracture is found tobe 5.6 and 2.6 GPa, respectively. The second instrument applies tension on a composite (aluminum-silicon dioxide) beam, 1 × 1.5 μm2 in cross section. The beam fails at 220 μN.In both the experiments, the samples are designed, patterned, and cofabricated with the instruments. The microinstruments' small size, low thermal mass, vacuum compatibility, and built-in vibration isolation allow material characterization to be performed over a wide range of environmental conditions: high vacuum (electron microscopy and surface analysis), high humidity, high pressure, and high and low temperatures.
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50

PARK, Sungil, Young-Soo HAN i Gwang-Min SUN. "Neutron Research Resumes at the Research Reactor HANARO". Physics and High Technology 31, nr 11 (30.11.2022): 2–8. http://dx.doi.org/10.3938/phit.31.042.

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HANARO, the only large-scale multipurpose research reactor in Korea, houses the neutron research facility with a diverse set of scientific instrumentation. After a long hiatus marred by trips and the following lengthy shutdowns, HANARO is now back on track. With the addition of the cold neutron source, new cold-neutron instruments are available with the previously operating thermal-neutron beam lines, making the total available neutron scattering instruments to users 9. While there is a plan to add an in-beam Mossbauer instrument and a Positron-annihilation spectrometer in the future, the focus is on recovering the user base at the moment. Achieving stable operation in the currently not-so-favorable regulatory environment remains a big challenge for the research facility.
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