High-resolution measurements of the exited states (n,pn, (n,dn C-12 cross sections

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Pillon M.

2017-01-01

Full Text Available Measurements of C12 cross sections for the excited states (n,p0 up to (n,p4 and (n,d0, (n,d1 have been carried out. The Van de Graaff neutron generator of the EC-JRC-IRMM laboratory has been used for these measurements. A very thin tritiated target (263 μg/cm2 was employed with deuteron beams energies impinging on the target in the range 2.5–4.0 MeV. Neutrons in the range 18.9–20.7 MeV were produced with an intrinsic energy spread of 0.2–0.25% FWHM. With such narrow neutron energy spread, using a high energy resolution device such as a single crystal diamond detector, several peaks from the outgoing charged particles produced by the (n,pn, (n,dn and also (n,α0 reactions appear in the pulse height spectrum. The peaks can be identified using the reaction Q-values. The diamond detector used for these measurements has shown an intrinsic energy resolution lower than 0.9% FWHM. The analysis of the peaks has permitted to derive the partial carbon reaction cross sections for several excited states. The results are presented in this paper with the associated uncertainties and they are compared with different versions of TENDL compilation when these data are available (e.g. versions 2009, 2010, 2011 and 2015 and also with experimental results available in the EXFOR database.

High-spatial resolution and high-spectral resolution detector for use in the measurement of solar flare hard x rays

International Nuclear Information System (INIS)

Desai, U.D.; Orwig, L.E.

1988-01-01

In the areas of high spatial resolution, the evaluation of a hard X-ray detector with 65 micron spatial resolution for operation in the energy range from 30 to 400 keV is proposed. The basic detector is a thick large-area scintillator faceplate, composed of a matrix of high-density scintillating glass fibers, attached to a proximity type image intensifier tube with a resistive-anode digital readout system. Such a detector, combined with a coded-aperture mask, would be ideal for use as a modest-sized hard X-ray imaging instrument up to X-ray energies as high as several hundred keV. As an integral part of this study it was also proposed that several techniques be critically evaluated for X-ray image coding which could be used with this detector. In the area of high spectral resolution, it is proposed to evaluate two different types of detectors for use as X-ray spectrometers for solar flares: planar silicon detectors and high-purity germanium detectors (HPGe). Instruments utilizing these high-spatial-resolution detectors for hard X-ray imaging measurements from 30 to 400 keV and high-spectral-resolution detectors for measurements over a similar energy range would be ideally suited for making crucial solar flare observations during the upcoming maximum in the solar cycle

Facility for the measurement of proton polarization in nuclear reactions

Energy Technology Data Exchange (ETDEWEB)

Slobodrian, R J; Irshad, M; Labrie, R; Rioux, C; Roy, R; Pigeon, R [Laval Univ., Quebec City (Canada). Lab. de Physique Nucleaire

1979-02-15

A polarimetry facility based on high resolution and high efficiency silicon polarimeters with on-line particle identification is described. It has proven its capability to measure polarization in (/sup 3/He, p(pol)) reaction with cross section levels of 40 ..mu..b/sr.

High-resolution measurements of x rays from ion-atom collisions

International Nuclear Information System (INIS)

Knudson, A.R.

1974-01-01

High resolution measurements of K x-ray spectra produced by ion-atom collisions at MeV energies are presented. These measurements indicate that a distribution of L-shell vacancies accompanies K-shell excitation. The variation of these spectra as a function of incident ion energy and atomic number is discussed. Difficulties in the analysis of these spectra due to rearrangement of vacancies between the time of the collision and the time of x-ray emission are considered. The use of high resolution x-ray measurements to obtain information on projectile ion vacancy configurations is demonstrated by data for Ar ions in KCl. X-ray spectra from Al projectiles in a variety of targets were measured and the effect of target composition on these spectra is discussed

Measuring large-scale social networks with high resolution.

Directory of Open Access Journals (Sweden)

Arkadiusz Stopczynski

Full Text Available This paper describes the deployment of a large-scale study designed to measure human interactions across a variety of communication channels, with high temporal resolution and spanning multiple years-the Copenhagen Networks Study. Specifically, we collect data on face-to-face interactions, telecommunication, social networks, location, and background information (personality, demographics, health, politics for a densely connected population of 1000 individuals, using state-of-the-art smartphones as social sensors. Here we provide an overview of the related work and describe the motivation and research agenda driving the study. Additionally, the paper details the data-types measured, and the technical infrastructure in terms of both backend and phone software, as well as an outline of the deployment procedures. We document the participant privacy procedures and their underlying principles. The paper is concluded with early results from data analysis, illustrating the importance of multi-channel high-resolution approach to data collection.

A high-resolution, multi-stop, time-to-digital converter for nuclear time-of-flight measurements

International Nuclear Information System (INIS)

Spencer, D.F.; Cole, J.; Drigert, M.; Aryaeinejad, R.

2006-01-01

A high-resolution, multi-stop, time-to-digital converter (TDC) was designed and developed to precisely measure the times-of-flight (TOF) of incident neutrons responsible for induced fission and capture reactions on actinide targets. The minimum time resolution is ±1 ns. The TDC design was implemented into a single, dual-wide CAMAC module. The CAMAC bus is used for command and control as well as an alternative data output. A high-speed ECL interface, compatible with LeCroy FERA modules, was also provided for the principle data output path. An Actel high-speed field programmable gate array (FPGA) chip was incorporated with an external oscillator and an internal multiple clock phasing system. This device implemented the majority of the high-speed register functions, the state machine for the FERA interface, and the high-speed counting circuit used for the TDC conversion. An external microcontroller was used to monitor and control system-level changes. In this work we discuss the performance of this TDC module as well as its application

High Resolution Temperature Measurement of Liquid Stainless Steel Using Hyperspectral Imaging

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Wim Devesse

2017-01-01

Full Text Available A contactless temperature measurement system is presented based on a hyperspectral line camera that captures the spectra in the visible and near infrared (VNIR region of a large set of closely spaced points. The measured spectra are used in a nonlinear least squares optimization routine to calculate a one-dimensional temperature profile with high spatial resolution. Measurements of a liquid melt pool of AISI 316L stainless steel show that the system is able to determine the absolute temperatures with an accuracy of 10%. The measurements are made with a spatial resolution of 12 µm/pixel, justifying its use in applications where high temperature measurements with high spatial detail are desired, such as in the laser material processing and additive manufacturing fields.

High-resolution neutron-diffraction measurements to 8 kbar

Science.gov (United States)

Bull, C. L.; Fortes, A. D.; Ridley, C. J.; Wood, I. G.; Dobson, D. P.; Funnell, N. P.; Gibbs, A. S.; Goodway, C. M.; Sadykov, R.; Knight, K. S.

2017-10-01

We describe the capability to measure high-resolution neutron powder diffraction data to a pressure of at least 8 kbar. We have used the HRPD instrument at the ISIS neutron source and a piston-cylinder design of pressure cell machined from a null-scattering titanium zirconium alloy. Data were collected under hydrostatic conditions from an elpasolite perovskite La?NiMnO?; by virtue of a thinner cell wall on the incident-beam side of the cell, it was possible to obtain data in the instrument's highest resolution back-scattering detector banks up to a maximum pressure of 8.5 kbar.

High resolution measurement of the 237Np(n,f) cross section from 100keV to 2MeV

International Nuclear Information System (INIS)

Plattard, S.; Pranal, Y.; Blons, J.

1975-01-01

237 Np fission is one of the reactions utilized in the threshold detector method of neutron spectrometry for the determination of fast neutron spectra in nuclear reactors. Therefore, an accurate knowledge of the energy-dependent fission cross section is essential for a precise generation of the spectral indices of this method. A high resolution measurement of the fission cross section is presented [fr

Method for local temperature measurement in a nanoreactor for in situ high-resolution electron microscopy.

Science.gov (United States)

Vendelbo, S B; Kooyman, P J; Creemer, J F; Morana, B; Mele, L; Dona, P; Nelissen, B J; Helveg, S

2013-10-01

In situ high-resolution transmission electron microscopy (TEM) of solids under reactive gas conditions can be facilitated by microelectromechanical system devices called nanoreactors. These nanoreactors are windowed cells containing nanoliter volumes of gas at ambient pressures and elevated temperatures. However, due to the high spatial confinement of the reaction environment, traditional methods for measuring process parameters, such as the local temperature, are difficult to apply. To address this issue, we devise an electron energy loss spectroscopy (EELS) method that probes the local temperature of the reaction volume under inspection by the electron beam. The local gas density, as measured using quantitative EELS, is combined with the inherent relation between gas density and temperature, as described by the ideal gas law, to obtain the local temperature. Using this method we determined the temperature gradient in a nanoreactor in situ, while the average, global temperature was monitored by a traditional measurement of the electrical resistivity of the heater. The local gas temperatures had a maximum of 56 °C deviation from the global heater values under the applied conditions. The local temperatures, obtained with the proposed method, are in good agreement with predictions from an analytical model. Copyright © 2013 Elsevier B.V. All rights reserved.

High-resolution ultrasonic spectroscopy

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V. Buckin

2018-03-01

Full Text Available High-resolution ultrasonic spectroscopy (HR-US is an analytical technique for direct and non-destructive monitoring of molecular and micro-structural transformations in liquids and semi-solid materials. It is based on precision measurements of ultrasonic velocity and attenuation in analysed samples. The application areas of HR-US in research, product development, and quality and process control include analysis of conformational transitions of polymers, ligand binding, molecular self-assembly and aggregation, crystallisation, gelation, characterisation of phase transitions and phase diagrams, and monitoring of chemical and biochemical reactions. The technique does not require optical markers or optical transparency. The HR-US measurements can be performed in small sample volumes (down to droplet size, over broad temperature range, at ambient and elevated pressures, and in various measuring regimes such as automatic temperature ramps, titrations and measurements in flow.

Cold-target recoil-ion momentum-spectroscopy: First results and future perspectives of a novel high resolution technique for the investigation of collision induced many-particle reactions

International Nuclear Information System (INIS)

Ullrich, J.; Doerner, R.; Mergel, V.; Jagutzki, O.; Spielberger, L.; Schmidt-Boecking, H.

1994-09-01

In order to investigate many-particle reaction dynamics in atomic collisions a novel high-resolution technique has been developed, which determines the momentum and the charge state of the slowly recoiling target ions. Using a very cold, thin, and localized supersonic gas jet target a momentum resolution of better than 0.05 a.u. is obtained by measuring the recoil-ion time-of-flight and the recoil-ion trajectory. Because of the very high detection efficiency of nearly 100% this technique is well suited for many-particle coincidence measurements in ionizing collisions. First experimental results for fast ion and electron impact on helium targets are presented. Future applications in atomic collision physics and related areas are discussed. (orig.)

Localized corrosion information using high resolution measurement devices

DEFF Research Database (Denmark)

Ambat, Rajan

2005-01-01

High performance demand for several engineering alloys and components, and miniaturization of electronics and development of MEMS requires better understanding of local corrosion characteristics frequently down to µm scale. This is because in metallic materials corrosion is a sensitive function...... in conjunction with microstructural analysis, using advanced microscopic tools, becomes very important. Corrosion of microelectronics circuits and MEMs is also a recent problem, which demands measurement resolution down to few microns as the components are extremely small, and measurement needs to be carried out...

High resolution spectroscopy of the 12Lambda B hypernucleus produced by the (e,e'K+) reaction.

Science.gov (United States)

Miyoshi, T; Sarsour, M; Yuan, L; Zhu, X; Ahmidouch, A; Ambrozewicz, P; Androic, D; Angelescu, T; Asaturyan, R; Avery, S; Baker, O K; Bertovic, I; Breuer, H; Carlini, R; Cha, J; Chrien, R; Christy, M; Cole, L; Danagoulian, S; Dehnhard, D; Elaasar, M; Empl, A; Ent, R; Fenker, H; Fujii, Y; Furic, M; Gan, L; Garrow, K; Gasparian, A; Gueye, P; Harvey, M; Hashimoto, O; Hinton, W; Hu, B; Hungerford, E; Jackson, C; Johnston, K; Juengst, H; Keppel, C; Lan, K; Liang, Y; Likhachev, V P; Liu, J H; Mack, D; Margaryan, A; Markowitz, P; Martoff, J; Mkrtchyan, H; Nakamura, S N; Petkovic, T; Reinhold, J; Roche, J; Sato, Y; Sawafta, R; Simicevic, N; Smith, G; Stepanyan, S; Tadevosyan, V; Takahashi, T; Tanida, K; Tang, L; Ukai, M; Uzzle, A; Vulcan, W; Wells, S; Wood, S; Xu, G; Yamaguchi, H; Yan, C

2003-06-13

High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique.

Functional high-resolution computed tomography of pulmonary vascular and airway reactions

International Nuclear Information System (INIS)

Herold, C.J.; Johns Hopkins Medical Institutions, Baltimore, MD; Brown, R.H.; Johns Hopkins Medical Institutions, Baltimore, MD; Johns Hopkins Medical Institutions, Baltimore, MD; Wetzel, R.C.; Herold, S.M.; Zeerhouni, E.A.

1993-01-01

We describe the use of high-resolution computed tomography (HRCT) for assessment of the function of pulmonary vessels and airways. With its excellent spatial resolution, HRCT is able to demonstrate pulmonary structures as small as 300 μm and can be used to monitor changes following various stimuli. HRCT also provides information about structures smaller than 300 μm through measurement of parenchymal background density. To date, sequential, spiral and ultrafast HRCT techniques have been used in a variety of challenges to gather information about the anatomical correlates of traditional physiological measurements, thus making anatomical-physiological correlation possible. HRCT of bronchial reactivity can demonstrate the location and time course of aerosol-induced broncho-constriction and may show changes not apparent on spirometry. HRCT of the pulmonary vascular system visualized adaptations of vessels during hypoxia and intravascular volume loading and elucidates cardiorespiratory interactions. Experimental studies provide a basis for potential clinical applications of this method. (orig.) [de

High-resolution transmission measurements of CO2 at high temperatures for industrial applications

DEFF Research Database (Denmark)

Evseev, Vadim; Fateev, Alexander; Clausen, Sønnik

2012-01-01

. The spectra have been recorded in a high-temperature flow gas cell and using a Fourier transform infrared (FTIR) spectrometer at a nominal resolution of 0.125 cm-1. The volume fractions of CO2 in the measurements were 1,10 and 100%. The measurements have been validated by comparison with medium...

Performance of high-resolution X-band radar for rainfall measurement in The Netherlands

Directory of Open Access Journals (Sweden)

C. Z. van de Beek

2010-02-01

Full Text Available This study presents an analysis of 195 rainfall events gathered with the X-band weather radar SOLIDAR and a tipping bucket rain gauge network near Delft, The Netherlands, between May 1993 and April 1994. The aim of this paper is to present a thorough analysis of a climatological dataset using a high spatial (120 m and temporal (16 s resolution X-band radar. This makes it a study of the potential for high-resolution rainfall measurements with non-polarimetric X-band radar over flat terrain. An appropriate radar reflectivity – rain rate relation is derived from measurements of raindrop size distributions and compared with radar – rain gauge data. The radar calibration is assessed using a long-term comparison of rain gauge measurements with corresponding radar reflectivities as well as by analyzing the evolution of the stability of ground clutter areas over time. Three different methods for ground clutter correction as well as the effectiveness of forward and backward attenuation correction algorithms have been studied. Five individual rainfall events are discussed in detail to illustrate the strengths and weaknesses of high-resolution X-band radar and the effectiveness of the presented correction methods. X-band radar is found to be able to measure the space-time variation of rainfall at high resolution, far greater than what can be achieved by rain gauge networks or a typical operational C-band weather radar. On the other hand, SOLIDAR can suffer from receiver saturation, wet radome attenuation as well as signal loss along the path. During very strong convective situations the signal can even be lost completely. In combination with several rain gauges for quality control, high resolution X-band radar is considered to be suitable for rainfall monitoring over relatively small (urban catchments. These results offer great prospects for the new high resolution polarimetric doppler X-band radar IDRA.

An Investigation of the Complexity of Maillard Reaction Product Profiles from the Thermal Reaction of Amino Acids with Sucrose Using High Resolution Mass Spectrometry

Directory of Open Access Journals (Sweden)

Agnieszka Golon

2014-08-01

Full Text Available Thermal treatment of food changes its chemical composition drastically with the formation of “so-called” Maillard reaction products, being responsible for the sensory properties of food, along with detrimental and beneficial health effects. In this contribution, we will describe the reactivity of several amino acids, including arginine, lysine, aspartic acid, tyrosine, serine and cysteine, with carbohydrates. The analytical strategy employed involves high and ultra-high resolution mass spectrometry followed by chemometric-type data analysis. The different reactivity of amino acids towards carbohydrates has been observed with cysteine and serine, resulting in complex MS spectra with thousands of detectable reaction products. Several compounds have been tentatively identified, including caramelization reaction products, adducts of amino acids with carbohydrates, their dehydration and hydration products, disproportionation products and aromatic compounds based on molecular formula considerations.

High-Resolution Measurement of the 4He(γ,n) Reaction in the Giant Resonance Region

International Nuclear Information System (INIS)

Nilsson, Bjoern

2003-03-01

A comprehensive near-threshold 4 He(gamma,n) absolute cross section measurement has been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. The 20 4 He target, and knocked-out neutrons were detected in a pair of 60 cm x 60 cm vetoed NE213A liquid scintillator arrays. The intense and varying charge-neutral experimental backgrounds were carefully quantified and removed from the data using a precision fitting procedure. Eight average laboratory angles (30, 45, 60, 75, 90, 105, 120, and 135 deg) were investigated for eight photon energy bins (25, 27, 29, 31, 35, 36, 39, and 41 MeV), resulting in 64 differential cross sections. These angular distributions were integrated to produce total cross sections as a function of photon energy. The resulting cross sections peak at 1.9 mb at a photon energy of 27 MeV, and fall off to a near-constant value of 1.1 mb by 36 MeV. Further, they are in excellent agreement with those measured by Sims et al. using tagged photons in the Quasi-Deuteron energy region. Overall, the results favor modern theoretical models which are based upon a charge-symmetric nucleon-nucleon force, in marked contrast to the recommendations made by Calarco et al. in 1983 based on the sparse 4 He(gamma,n) data available at the time

High resolution wind turbine wake measurements with a scanning lidar

DEFF Research Database (Denmark)

Herges, T. G.; Maniaci, D. C.; Naughton, B. T.

2017-01-01

High-resolution lidar wake measurements are part of an ongoing field campaign being conducted at the Scaled Wind Farm Technology facility by Sandia National Laboratories and the National Renewable Energy Laboratory using a customized scanning lidar from the Technical University of Denmark. One...

High-resolution axial MR imaging of tibial stress injuries

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Mammoto Takeo

2012-05-01

Full Text Available Abstract Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries.

High-resolution axial MR imaging of tibial stress injuries

Science.gov (United States)

2012-01-01

Purpose To evaluate the relative involvement of tibial stress injuries using high-resolution axial MR imaging and the correlation with MR and radiographic images. Methods A total of 33 patients with exercise-induced tibial pain were evaluated. All patients underwent radiograph and high-resolution axial MR imaging. Radiographs were taken at initial presentation and 4 weeks later. High-resolution MR axial images were obtained using a microscopy surface coil with 60 × 60 mm field of view on a 1.5T MR unit. All images were evaluated for abnormal signals of the periosteum, cortex and bone marrow. Results Nineteen patients showed no periosteal reaction at initial and follow-up radiographs. MR imaging showed abnormal signals in the periosteal tissue and partially abnormal signals in the bone marrow. In 7 patients, periosteal reaction was not seen at initial radiograph, but was detected at follow-up radiograph. MR imaging showed abnormal signals in the periosteal tissue and entire bone marrow. Abnormal signals in the cortex were found in 6 patients. The remaining 7 showed periosteal reactions at initial radiograph. MR imaging showed abnormal signals in the periosteal tissue in 6 patients. Abnormal signals were seen in the partial and entire bone marrow in 4 and 3 patients, respectively. Conclusions Bone marrow abnormalities in high-resolution axial MR imaging were related to periosteal reactions at follow-up radiograph. Bone marrow abnormalities might predict later periosteal reactions, suggesting shin splints or stress fractures. High-resolution axial MR imaging is useful in early discrimination of tibial stress injuries. PMID:22574840

High-resolution gamma-ray measurement systems using a compact electro- mechanically cooled detector system and intelligent software

International Nuclear Information System (INIS)

Buckley, W.M.; Carlson, J.B.; Neufeld, K.W.

1995-01-01

Obtaining high-resolution gamma-ray measurements using high-purity germanium (HPGe) detectors in the field has been of limited practicality due to the need to use and maintain a supply of liquid nitrogen (LN 2 ). This same constraint limits high-resolution gamma measurements in unattended safeguards or treaty Verification applications. We are developing detectors and software to greatly extend the applicability of high-resolution germanium-based measurements for these situations

Two-photon high-resolution measurement of partial pressure of oxygen in cerebral vasculature and tissue.

Science.gov (United States)

Sakadzić, Sava; Roussakis, Emmanuel; Yaseen, Mohammad A; Mandeville, Emiri T; Srinivasan, Vivek J; Arai, Ken; Ruvinskaya, Svetlana; Devor, Anna; Lo, Eng H; Vinogradov, Sergei A; Boas, David A

2010-09-01

Measurements of oxygen partial pressure (pO(2)) with high temporal and spatial resolution in three dimensions is crucial for understanding oxygen delivery and consumption in normal and diseased brain. Among existing pO(2) measurement methods, phosphorescence quenching is optimally suited for the task. However, previous attempts to couple phosphorescence with two-photon laser scanning microscopy have faced substantial difficulties because of extremely low two-photon absorption cross-sections of conventional phosphorescent probes. Here we report to our knowledge the first practical in vivo two-photon high-resolution pO(2) measurements in small rodents' cortical microvasculature and tissue, made possible by combining an optimized imaging system with a two-photon-enhanced phosphorescent nanoprobe. The method features a measurement depth of up to 250 microm, sub-second temporal resolution and requires low probe concentration. The properties of the probe allowed for direct high-resolution measurement of cortical extravascular (tissue) pO(2), opening many possibilities for functional metabolic brain studies.

Two-photon high-resolution measurement of partial pressure of oxygen in cerebral vasculature and tissue

Science.gov (United States)

Sakadžić, Sava; Roussakis, Emmanuel; Yaseen, Mohammad A.; Mandeville, Emiri T.; Srinivasan, Vivek J.; Arai, Ken; Ruvinskaya, Svetlana; Devor, Anna; Lo, Eng H.; Vinogradov, Sergei A.; Boas, David A.

2010-01-01

The ability to measure oxygen partial pressure (pO2) with high temporal and spatial resolution in three dimensions is crucial for understanding oxygen delivery and consumption in normal and diseased brain. Among existing pO2 measurement methods, phosphorescence quenching is optimally suited for the task. However, previous attempts to couple phosphorescence with two-photon laser scanning microscopy have faced substantial difficulties because of extremely low two-photon absorption cross-sections of conventional phosphorescent probes. Here, we report the first practical in vivo two-photon high-resolution pO2 measurements in small rodents’ cortical microvasculature and tissue, made possible by combining an optimized imaging system with a two-photon-enhanced phosphorescent nanoprobe. The method features a measurement depth of up to 250 µm, sub-second temporal resolution and requires low probe concentration. Most importantly, the properties of the probe allowed for the first direct high-resolution measurement of cortical extravascular (tissue) pO2, opening numerous possibilities for functional metabolic brain studies. PMID:20693997

High resolution wind measurements for offshore wind energy development

Science.gov (United States)

Nghiem, Son Van (Inventor); Neumann, Gregory (Inventor)

2013-01-01

A method, apparatus, system, article of manufacture, and computer readable storage medium provide the ability to measure wind. Data at a first resolution (i.e., low resolution data) is collected by a satellite scatterometer. Thin slices of the data are determined. A collocation of the data slices are determined at each grid cell center to obtain ensembles of collocated data slices. Each ensemble of collocated data slices is decomposed into a mean part and a fluctuating part. The data is reconstructed at a second resolution from the mean part and a residue of the fluctuating part. A wind measurement is determined from the data at the second resolution using a wind model function. A description of the wind measurement is output.

High energy resolution measurement of the sup 238 U neutron capture yield from 1 to 100 keV

Energy Technology Data Exchange (ETDEWEB)

Macklin, R.L. (Tennessee Univ., Knoxville, TN (United States). Dept. of Nuclear Engineering); Perez, R.B. (Tennessee Univ., Knoxville, TN (United States). Dept. of Nuclear Engineering Oak Ridge National Lab., TN (United States)); De Saussure, G.; Ingle, R.W. (Oak Ridge National Lab., TN (United States))

1991-01-01

The purpose of this work is the precise determination of the {sup 238}U neutron capture yield (i.e. the probability of neutron capture) as a function of neutron energy with the highest available neutron energy resolution. The motivation for this undertaking arises from the central role played by the {sup 238}U neutron capture process in the neutron balance of both thermal reactors and fast breeder reactors. The present measurement was performed using the Oak Ridge Electron Linear Accelerator (ORELA) facility. The pulsed beam of neutrons from the ORELA facility is collimated on a sample of {sup 238}U. The neutron capture rate in the sample is measured, as a function of neutron time-of-flight (TOF) by detecting the {gamma}-rays from the {sup 238}U(n, {gamma}){sup 239}U reaction with a large {gamma}-ray detector surrounding the {sup 238}U sample. At each energy, the capture yield is proportional to the observed capture rate divided by the measured intensity of the neutron beam. The constant of proportionality (the normalization constant) is obtained from the ratio of theoretical to experimentally measured areas under small {sup 238}U resonances where the resonance parameters have been determined from high-resolution {sup 238}U transmission measurements. The cross section for the reaction {sup 238}U(n,{gamma}){sup 239}U can be derived from the measured capture yield if one applies appropriate corrections for multiple scattering and resonance self-shielding. Some 200 {sup 238}U neutron resonances in the energy range from 250 eV to 10 keV have been observed which had not been detected in previous measurements. (author).

High-resolution study of the Gamow-Teller strength distribution in the light nuclei 9B and 13N using the (3He,t) charge-exchange reaction at 420 MeV beam energy

International Nuclear Information System (INIS)

Scholl, Clemens

2010-01-01

Excited states in the light nuclei 9 B and 13 C were studied using the ( 3 He,t) charge-exchange reaction on 9 Be and 13 C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The 3 He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ( 3 He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in 13 N were studied, and a total of 20 states were observed in 9 B. Of these, 9 states in 13 C and 10 states in 9 B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei 9 B and 13 N. The only charge-exchange study of 9 B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in 9 B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The results point to a strong difference in spatial structure between the

High-Resolution Wind Measurements for Offshore Wind Energy Development

Science.gov (United States)

Nghiem, Son V.; Neumann, Gregory

2011-01-01

A mathematical transform, called the Rosette Transform, together with a new method, called the Dense Sampling Method, have been developed. The Rosette Transform is invented to apply to both the mean part and the fluctuating part of a targeted radar signature using the Dense Sampling Method to construct the data in a high-resolution grid at 1-km posting for wind measurements over water surfaces such as oceans or lakes.

High resolution simultaneous measurements of airborne radionuclides

International Nuclear Information System (INIS)

Abe, T.; Yamaguchi, Y.; Tanaka, K.; Komura, K.

2006-01-01

High resolution (2-3 hrs) simultaneous measurements of airborne radionuclides, 212 Pb, 210 Pb and 7 Be, have been performed by using extremely low background Ge detectors at Ogoya Underground Laboratory. We have measured above radionuclides at three monitoring points viz, 1) Low Level Radioactivity Laboratory (LLRL) Kanazawa University, 2) Shishiku Plateau (640 m MSL) located about 8 km from LLRL to investigate vertical difference of activity levels, and 3) Hegura Island (10 m MSL) located about 50 km from Noto Peninsula in the Sea of Japan to evaluate the influences of Asian continent or mainland of Japan on the variation to the activity levels. Variations of short-lived 212 Pb concentration showed noticeable time lags between at LLRL and at Shishiku Plateau. These time lags might be caused by change of height of a planetary boundary layer. On the contrary, variations of long-lived 210 Pb and 7 Be showed simultaneity at three locations because of homogeneity of these concentrations all over the area. (author)

Dynamic frequency-domain interferometer for absolute distance measurements with high resolution

International Nuclear Information System (INIS)

Weng, Jidong; Liu, Shenggang; Ma, Heli; Tao, Tianjiong; Wang, Xiang; Liu, Cangli; Tan, Hua

2014-01-01

A unique dynamic frequency-domain interferometer for absolute distance measurement has been developed recently. This paper presents the working principle of the new interferometric system, which uses a photonic crystal fiber to transmit the wide-spectrum light beams and a high-speed streak camera or frame camera to record the interference stripes. Preliminary measurements of harmonic vibrations of a speaker, driven by a radio, and the changes in the tip clearance of a rotating gear wheel show that this new type of interferometer has the ability to perform absolute distance measurements both with high time- and distance-resolution

Dynamic frequency-domain interferometer for absolute distance measurements with high resolution

Science.gov (United States)

Weng, Jidong; Liu, Shenggang; Ma, Heli; Tao, Tianjiong; Wang, Xiang; Liu, Cangli; Tan, Hua

2014-11-01

A unique dynamic frequency-domain interferometer for absolute distance measurement has been developed recently. This paper presents the working principle of the new interferometric system, which uses a photonic crystal fiber to transmit the wide-spectrum light beams and a high-speed streak camera or frame camera to record the interference stripes. Preliminary measurements of harmonic vibrations of a speaker, driven by a radio, and the changes in the tip clearance of a rotating gear wheel show that this new type of interferometer has the ability to perform absolute distance measurements both with high time- and distance-resolution.

High Spectral Resolution Lidar Based on a Potassium Faraday Dispersive Filter for Daytime Temperature Measurement

Directory of Open Access Journals (Sweden)

Abo Makoto

2016-01-01

Full Text Available In this paper, a new high-spectral-resolution lidar technique is proposed for measuring the profiles of atmospheric temperature in daytime. Based on the theory of high resolution Rayleigh scattering, the feasibility and advantages of using potassium (K Faraday dispersive optical filters as blocking filters for measuring atmospheric temperature are demonstrated with a numerical simulation. It was found that temperature profiles could be measured within 1K error for the height of 9 km with a 500 m range resolution in 60 min by using laser pulses with 1mJ/pulse and 1 kHz, and a 50 cm diameter telescope. Furthermore, we are developing compact pulsed laser system for temperature lidar transmitter.

Fallspeed measurement and high-resolution multi-angle photography of hydrometeors in freefall

OpenAIRE

T. J. Garrett; C. Fallgatter; K. Shkurko; D. Howlett

2012-01-01

We describe here a new instrument for imaging hydrometeors in freefall. The Multi-Angle Snowflake Camera (MASC) captures high resolution photographs of hydrometeors from three angles while simultaneously measuring their fallspeed. Based on the stereoscopic photographs captured over the two months of continuous measurements obtained at a high altitude location within the Wasatch Front in Utah, we derive statistics for fallspeed, hydrometeor size, shape, orientation and aspect ratio. From a sel...

The high-resolution extraterrestrial solar spectrum (QASUMEFTS determined from ground-based solar irradiance measurements

Directory of Open Access Journals (Sweden)

J. Gröbner

2017-09-01

Full Text Available A high-resolution extraterrestrial solar spectrum has been determined from ground-based measurements of direct solar spectral irradiance (SSI over the wavelength range from 300 to 500 nm using the Langley-plot technique. The measurements were obtained at the Izaña Atmospheric Research Centre from the Agencia Estatal de Meteorología, Tenerife, Spain, during the period 12 to 24 September 2016. This solar spectrum (QASUMEFTS was combined from medium-resolution (bandpass of 0.86 nm measurements of the QASUME (Quality Assurance of Spectral Ultraviolet Measurements in Europe spectroradiometer in the wavelength range from 300 to 500 nm and high-resolution measurements (0.025 nm from a Fourier transform spectroradiometer (FTS over the wavelength range from 305 to 380 nm. The Kitt Peak solar flux atlas was used to extend this high-resolution solar spectrum to 500 nm. The expanded uncertainties of this solar spectrum are 2 % between 310 and 500 nm and 4 % at 300 nm. The comparison of this solar spectrum with solar spectra measured in space (top of the atmosphere gave very good agreements in some cases, while in some other cases discrepancies of up to 5 % were observed. The QASUMEFTS solar spectrum represents a benchmark dataset with uncertainties lower than anything previously published. The metrological traceability of the measurements to the International System of Units (SI is assured by an unbroken chain of calibrations leading to the primary spectral irradiance standard of the Physikalisch-Technische Bundesanstalt in Germany.

Compact high-resolution echelle-AOTF NIR spectrometer for atmospheric measurements

Science.gov (United States)

Korablev, Oleg I.; Bertaux, Jean-Loup; Vinogradov, Imant I.; Kalinnikov, Yurii K.; Nevejans, D.; Neefs, E.; Le Barbu, T.; Durry, G.

2017-11-01

A new concept of a high-resolution near-IR spectrometer consisting of an echelle grating combined with an acousto-optic tunable filter (AOTF) for separation of diffraction orders, is developed for space-borne studies of planetary atmospheres. A compact design with no moving parts within the mass budget of 3-5 kg allows to reach the resolving power λ/Δλ of 20000-30000. Only a small piece of spectrum in high diffraction orders can be measured at a time, but thanks to flexibility of the AOTF electrical tuning, such pieces of spectrum can be measured randomly and rapidly within the spectral range. This development can be used for accurate measurements of important atmospheric gases, such as CO2 in terrestrial atmosphere, isotopic ratios and minor gases. A spectrometer, based on this principle, SOIR (Solar Occultation InfraRed) is being built for Venus Express (2005) ESA mission. Instruments based on this principle have high potential for the studies of the Earth, in particular for measurements of isotopes of water in the lower atmosphere, either in solar occultation profiling (tangent altitude <10 km), or observing solar glint for integral quantities of the components. Small size of hardware makes them ideal for micro-satellites, which are now agile enough to provide necessary pointing for solar occultation or glint observations. Also, the atmosphere of Mars has never been observed at local scales with such a high spectral resolution. A laboratory prototype consisting of 275-mm echelle spectrometer with Hamamatsu InGaAs 512-pixel linear array and the AOTF has demonstrated λ/Δλ≍30000 in the spectral range of 1-1.7 μm. The next set up, covering the spectral ranges of 1-1.7 μm and 2.3-4.3 μm, and the Venus Express SOIR are briefly discussed.

High speed, High resolution terahertz spectrometers

International Nuclear Information System (INIS)

Kim, Youngchan; Yee, Dae Su; Yi, Miwoo; Ahn, Jaewook

2008-01-01

A variety of sources and methods have been developed for terahertz spectroscopy during almost two decades. Terahertz time domain spectroscopy (THz TDS)has attracted particular attention as a basic measurement method in the fields of THz science and technology. Recently, asynchronous optical sampling (AOS)THz TDS has been demonstrated, featuring rapid data acquisition and a high spectral resolution. Also, terahertz frequency comb spectroscopy (TFCS)possesses attractive features for high precision terahertz spectroscopy. In this presentation, we report on these two types of terahertz spectrometer. Our high speed, high resolution terahertz spectrometer is demonstrated using two mode locked femtosecond lasers with slightly different repetition frequencies without a mechanical delay stage. The repetition frequencies of the two femtosecond lasers are stabilized by use of two phase locked loops sharing the same reference oscillator. The time resolution of our terahertz spectrometer is measured using the cross correlation method to be 270 fs. AOS THz TDS is presented in Fig. 1, which shows a time domain waveform rapidly acquired on a 10ns time window. The inset shows a zoom into the signal with 100ps time window. The spectrum obtained by the fast Fourier Transformation (FFT)of the time domain waveform has a frequency resolution of 100MHz. The dependence of the signal to noise ratio (SNR)on the measurement time is also investigated

Depth of interaction resolution measurements for a high resolution PET detector using position sensitive avalanche photodiodes

International Nuclear Information System (INIS)

Yang Yongfeng; Dokhale, Purushottam A; Silverman, Robert W; Shah, Kanai S; McClish, Mickel A; Farrell, Richard; Entine, Gerald; Cherry, Simon R

2006-01-01

We explore dual-ended read out of LSO arrays with two position sensitive avalanche photodiodes (PSAPDs) as a high resolution, high efficiency depth-encoding detector for PET applications. Flood histograms, energy resolution and depth of interaction (DOI) resolution were measured for unpolished LSO arrays with individual crystal sizes of 1.0, 1.3 and 1.5 mm, and for a polished LSO array with 1.3 mm pixels. The thickness of the crystal arrays was 20 mm. Good flood histograms were obtained for all four arrays, and crystals in all four arrays can be clearly resolved. Although the amplitude of each PSAPD signal decreases as the interaction depth moves further from the PSAPD, the sum of the two PSAPD signals is essentially constant with irradiation depth for all four arrays. The energy resolutions were similar for all four arrays, ranging from 14.7% to 15.4%. A DOI resolution of 3-4 mm (including the width of the irradiation band which is ∼2 mm) was obtained for all the unpolished arrays. The best DOI resolution was achieved with the unpolished 1 mm array (average 3.5 mm). The DOI resolution for the 1.3 mm and 1.5 mm unpolished arrays was 3.7 and 4.0 mm respectively. For the polished array, the DOI resolution was only 16.5 mm. Summing the DOI profiles across all crystals for the 1 mm array only degraded the DOI resolution from 3.5 mm to 3.9 mm, indicating that it may not be necessary to calibrate the DOI response separately for each crystal within an array. The DOI response of individual crystals in the array confirms this finding. These results provide a detailed characterization of the DOI response of these PSAPD-based PET detectors which will be important in the design and calibration of a PET scanner making use of this detector approach

High-Resolution Measurement of the {sup 4}He({gamma},n) Reaction in the Giant Resonance Region

Energy Technology Data Exchange (ETDEWEB)

Nilsson, Bjoern

2003-03-01

A comprehensive near-threshold {sup 4}He(gamma,n) absolute cross section measurement has been performed at the high-resolution tagged-photon facility MAX-lab located in Lund, Sweden. The 20 < Eg < 45 MeV tagged photons (covering the Giant Dipole Resonance energy region) were directed towards a liquid {sup 4}He target, and knocked-out neutrons were detected in a pair of 60 cm x 60 cm vetoed NE213A liquid scintillator arrays. The intense and varying charge-neutral experimental backgrounds were carefully quantified and removed from the data using a precision fitting procedure. Eight average laboratory angles (30, 45, 60, 75, 90, 105, 120, and 135 deg) were investigated for eight photon energy bins (25, 27, 29, 31, 35, 36, 39, and 41 MeV), resulting in 64 differential cross sections. These angular distributions were integrated to produce total cross sections as a function of photon energy. The resulting cross sections peak at 1.9 mb at a photon energy of 27 MeV, and fall off to a near-constant value of 1.1 mb by 36 MeV. Further, they are in excellent agreement with those measured by Sims et al. using tagged photons in the Quasi-Deuteron energy region. Overall, the results favor modern theoretical models which are based upon a charge-symmetric nucleon-nucleon force, in marked contrast to the recommendations made by Calarco et al. in 1983 based on the sparse {sup 4}He(gamma,n) data available at the time.

A high-resolution x-ray spectrometer for a kaon mass measurement

Energy Technology Data Exchange (ETDEWEB)

Phelan, Kevin, E-mail: kevin.phelan@oeaw.ac.at [Stefan Meyer Institute for Subatomic Physics of The Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna (Austria); Suzuki, Ken; Zmeskal, Johann [Stefan Meyer Institute for Subatomic Physics of The Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna (Austria); Tortorella, Daniele [Payr Engineering GmbH, Wiederschwing 25, A-9564 Patergassen (Austria); Bühler, Matthias; Hertrich, Theo [Low Temperature Solutions UG, Bahnhofstraße 21, D-85737 Ismaning (Germany)

2017-02-11

The ASPECT consortium (Adaptable Spectrometer Enabled by Cryogenic Technology) is currently constructing a generalised cryogenic platform for cryogenic detector work which will be able to accommodate a wide range of sensors. The cryogenics system is based on a small mechanical cooler with a further adiabatic demagnetisation stage and will work with cryogenic detectors at sub-Kelvin temperatures. The commercial aim of the consortium is to produce a compact, user-friendly device with an emphasis on reliability and portability which can easily be transported for specialised on-site work, such as beam-lines or telescope facilities. The cryogenic detector platform will accommodate a specially developed cryogenic sensor, either a metallic magnetic calorimeter or a magnetic penetration-depth thermometer. The detectors will be designed to work in various temperatures regions with an emphasis on optimising the various detector resolutions for specific temperatures. One resolution target is of about 10 eV at the energies range typically created in kaonic atoms experiments (soft x-ray energies). A following step will see the introduction of continuous, high-power, sub-Kelvin cooling which will bring the cryogenic basis for a high resolution spectrometer system to the market. The scientific goal of the project will produce an experimental set-up optimised for kaon-mass measurements performing high-resolution x-ray spectroscopy on a beam-line provided foreseeably by the J-PARC (Tokai, Japan) or DAΦNE (Frascati, Italy) facilities.

Development of high speed integrated circuit for very high resolution timing measurements

International Nuclear Information System (INIS)

Mester, Christian

2009-10-01

A multi-channel high-precision low-power time-to-digital converter application specific integrated circuit for high energy physics applications has been designed and implemented in a 130 nm CMOS process. To reach a target resolution of 24.4 ps, a novel delay element has been conceived. This nominal resolution has been experimentally verified with a prototype, with a minimum resolution of 19 ps. To further improve the resolution, a new interpolation scheme has been described. The ASIC has been designed to use a reference clock with the LHC bunch crossing frequency of 40 MHz and generate all required timing signals internally, to ease to use within the framework of an LHC upgrade. Special care has been taken to minimise the power consumption. (orig.)

Development of high speed integrated circuit for very high resolution timing measurements

Energy Technology Data Exchange (ETDEWEB)

Mester, Christian

2009-10-15

A multi-channel high-precision low-power time-to-digital converter application specific integrated circuit for high energy physics applications has been designed and implemented in a 130 nm CMOS process. To reach a target resolution of 24.4 ps, a novel delay element has been conceived. This nominal resolution has been experimentally verified with a prototype, with a minimum resolution of 19 ps. To further improve the resolution, a new interpolation scheme has been described. The ASIC has been designed to use a reference clock with the LHC bunch crossing frequency of 40 MHz and generate all required timing signals internally, to ease to use within the framework of an LHC upgrade. Special care has been taken to minimise the power consumption. (orig.)

High resolution X-ray photoelectron spectroscopy of styrene oxide adsorption and reaction on Ag(1 1 1)

Science.gov (United States)

Piao, H.; Enever, M. C. N.; Adib, K.; Hrbek, J.; Barteau, M. A.

2004-11-01

Synchrotron-based X-ray photoelectron spectroscopy (XPS) has been used to investigate the adsorption and reaction of styrene oxide on Ag(1 1 1). When adsorption is carried out at 250 K or above, ring opening of styrene oxide forms a stable surface oxametallacycle intermediate which eventually reacts at 485 K to regenerate styrene oxide. High resolution XPS is capable of distinguishing the oxametallacycle from molecularly adsorbed and condensed styrene oxide on the basis of different C1s peak separations. The observed separations are well accounted for by the results of DFT calculations.

High-resolution study of the Gamow-Teller strength distribution in the light nuclei {sup 9}B and {sup 13}N using the ({sup 3}He,t) charge-exchange reaction at 420 MeV beam energy

Energy Technology Data Exchange (ETDEWEB)

Scholl, Clemens

2010-07-07

Excited states in the light nuclei {sup 9}B and {sup 13}C were studied using the ({sup 3}He,t) charge-exchange reaction on {sup 9}Be and {sup 13}C targets. The measurements were performed at the research center for nuclear physics (RCNP) in Osaka, Japan, using the magnetic spectrometer Grand Raiden and the dispersive WS course. The {sup 3}He beam with an energy of 420 MeV was accelerated by the RCNP Ring Cyclotron. The Grand Raiden spectrometer and the WS course allow to study the ({sup 3}He,t) charge-exchange reaction with an energy resolution of around 30 keV, which is one order of magnitude better than measurements with the (p,n) charge-exchange reaction. The high resolution allows to better separate individual states and to determine weak excitation strengths because of low background in the spectra. A total of 19 states in {sup 13}N were studied, and a total of 20 states were observed in {sup 9}B. Of these, 9 states in {sup 13}C and 10 states in {sup 9}B were identified as being excited by a Gamow-Teller transition. Charge-exchange reactions are related to beta-decay, and at zero momentum transfer a simple proportionality exists between the cross-section of the charge-exchange experiment and the Fermi (F) or Gamow-Teller (GT) beta-decay strength. While the Fermi strength B(F) is concentrated in the transition to the isobaric analog state, the Gamow-Teller strength B(GT) is scattered among the excited states. The main aim of the present study is to determine the B(GT) strengths in the nuclei {sup 9}B and {sup 13}N. The only charge-exchange study of {sup 9}B was made 30 years ago with the (p,n) reaction and a resolution of around 300-400 keV. Many states, especially at high excitation energy, could not be resolved by that study. The present work was able to separate many weakly excited states with small decay width at high excitation energies (12-19 MeV) in {sup 9}B and determine the B(GT) strength distribution by using recent high-precision beta-decay data. The

High-resolution study of Gamow-Teller transitions in the 47Ti(3He,t)47V reaction

Science.gov (United States)

Ganioǧlu, E.; Fujita, H.; Fujita, Y.; Adachi, T.; Algora, A.; Csatlós, M.; Deaven, J. M.; Estevez-Aguado, E.; Guess, C. J.; Gulyás, J.; Hatanaka, K.; Hirota, K.; Honma, M.; Ishikawa, D.; Krasznahorkay, A.; Matsubara, H.; Meharchand, R.; Molina, F.; Okamura, H.; Ong, H. J.; Otsuka, T.; Perdikakis, G.; Rubio, B.; Scholl, C.; Shimbara, Y.; Susoy, G.; Suzuki, T.; Tamii, A.; Thies, J. H.; Zegers, R. G. T.; Zenihiro, J.

2013-01-01

Given the importance of Gamow-Teller (GT) transitions in nuclear structure and astrophysical nuclear processes, we have studied Tz=+3/2→+1/2, GT transitions starting from the 47Ti nucleus in the (3He,t) charge-exchange reaction at 0∘ and at an intermediate incident energy of 140 MeV/nucleon. The experiments were carried out at the Research Center for Nuclear Physics (RCNP), Osaka, using the high-resolution facility with a high-dispersion beam line and the Grand-Raiden spectrometer. With an energy resolution of 20 keV, individual GT transitions were observed and GT strength was derived for each state populated up to an excitation energy (Ex) of 12.5 MeV. The GT strength was widely distributed from low excitation energy up to 12.5 MeV, where we had to stop the analysis because of the high level density. The distribution of the GT strengths was compared with the results of shell model calculations using the GXPF1 interaction. The calculations could reproduce the experimental GT distributions well. The GT transitions from the ground state of 47Ti and the M1 transitions from the isobaric analog state in 47V to the same low-lying states in 47V are analogous. It was found that the ratios of GT transition strengths to the ground state, the 0.088-MeV state, and the 0.146-MeV state are similar to the ratios of the strengths of the analogous M1 transitions from the isobaric analog state (IAS) to these states. The measured distribution of the GT strengths was also compared with those starting from the Tz=+3/2 nucleus 41K to the Tz=+1/2 nucleus 41Ca.

High-resolution thermal expansion measurements under helium-gas pressure

Science.gov (United States)

Manna, Rudra Sekhar; Wolf, Bernd; de Souza, Mariano; Lang, Michael

2012-08-01

We report on the realization of a capacitive dilatometer, designed for high-resolution measurements of length changes of a material for temperatures 1.4 K ⩽ T ⩽ 300 K and hydrostatic pressure P ⩽ 250 MPa. Helium (4He) is used as a pressure-transmitting medium, ensuring hydrostatic-pressure conditions. Special emphasis has been given to guarantee, to a good approximation, constant-pressure conditions during temperature sweeps. The performance of the dilatometer is demonstrated by measurements of the coefficient of thermal expansion at pressures P ≃ 0.1 MPa (ambient pressure) and 104 MPa on a single crystal of azurite, Cu3(CO3)2(OH)2, a quasi-one-dimensional spin S = 1/2 Heisenberg antiferromagnet. The results indicate a strong effect of pressure on the magnetic interactions in this system.

Complete dipole response in 208Pb from high-resolution polarized proton scattering at 0 deg

International Nuclear Information System (INIS)

Neumann-Cosel, P. von; Kalmykov, Y.; Poltoratska, I.; Ponomarev, V. Yu.; Richter, A.; Wambach, J.; Adachi, T.; Fujita, Y.; Matsubara, H.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Yosoi, M.; Bertulani, C. A.; Carter, J.; Fujita, H.; Dozono, M.; Fujita, K.; Hashimoto, H.; Hatanaka, K.

2009-01-01

The structure of electric and magnetic dipole modes in 208 Pb is investigated in a high-resolution measurement of the (p-vector,p-vector') reaction under 0 deg. First results on the E1 strength in the region of the pygmy dipole resonance are reported.

A digital approach for real time high-rate high-resolution radiation measurements

International Nuclear Information System (INIS)

Gerardi, G.; Abbene, L.

2014-01-01

Modern spectrometers are currently developed by using digital pulse processing (DPP) systems, showing several advantages over traditional analog electronics. The aim of this work is to present digital strategies, in a time domain, for the development of real time high-rate high-resolution spectrometers. We propose a digital method, based on the single delay line (SDL) shaping technique, able to perform multi-parameter analysis with high performance even at high photon counting rates. A robust pulse shape and height analysis (PSHA), applied on single isolated time windows of the detector output waveforms, is presented. The potentialities of the proposed strategy are highlighted through both theoretical and experimental approaches. To strengthen our approach, the implementation of the method on a real-time system together with some experimental results are presented. X-ray spectra measurements with a semiconductor detector are performed both at low and high photon counting rates (up to 1.1 Mcps)

A digital approach for real time high-rate high-resolution radiation measurements

Energy Technology Data Exchange (ETDEWEB)

Gerardi, G.; Abbene, L., E-mail: leonardo.abbene@unipa.it

2014-12-21

Modern spectrometers are currently developed by using digital pulse processing (DPP) systems, showing several advantages over traditional analog electronics. The aim of this work is to present digital strategies, in a time domain, for the development of real time high-rate high-resolution spectrometers. We propose a digital method, based on the single delay line (SDL) shaping technique, able to perform multi-parameter analysis with high performance even at high photon counting rates. A robust pulse shape and height analysis (PSHA), applied on single isolated time windows of the detector output waveforms, is presented. The potentialities of the proposed strategy are highlighted through both theoretical and experimental approaches. To strengthen our approach, the implementation of the method on a real-time system together with some experimental results are presented. X-ray spectra measurements with a semiconductor detector are performed both at low and high photon counting rates (up to 1.1 Mcps)

High resolution measurements and modeling of auroral hydrogen emission line profiles

Directory of Open Access Journals (Sweden)

B. S. Lanchester

Full Text Available Measurements in the visible wavelength range at high spectral resolution (1.3 Å have been made at Longyearbyen, Svalbard (15.8 E,78.2 N during an interval of intense proton precipitation. The shape and Doppler shift of hydrogen Balmer beta line profiles have been compared with model line profiles, using as input ion energy spectra from almost coincident passes of the FAST and DMSP spacecraft. The comparison shows that the simulation contains the important physical processes that produce the profiles, and confirms that measured changes in the shape and peak wave-length of the hydrogen profiles are the result of changing energy input. This combination of high resolution measurements with modeling provides a method of estimating the incoming energy and changes in flux of precipitating protons over Svalbard, for given energy and pitch-angle distributions. Whereas for electron precipitation, information on the incident particles is derived from brightness and brightness ratios which require at least two spectral windows, for proton precipitation the Doppler profile of resulting hydrogen emission is directly related to the energy and energy flux of the incident energetic protons and can be used to gather information about the source region. As well as the expected Doppler shift to shorter wavelengths, the measured profiles have a significant red-shifted component, the result of upward flowing emitting hydrogen atoms.

Key words. Ionosphere (auroral ionosphere; particle precipitation – Magnetospheric physics (auroral phenomena

High resolution measurements and modeling of auroral hydrogen emission line profiles

Directory of Open Access Journals (Sweden)

B. S. Lanchester

2003-07-01

Full Text Available Measurements in the visible wavelength range at high spectral resolution (1.3 Å have been made at Longyearbyen, Svalbard (15.8 E,78.2 N during an interval of intense proton precipitation. The shape and Doppler shift of hydrogen Balmer beta line profiles have been compared with model line profiles, using as input ion energy spectra from almost coincident passes of the FAST and DMSP spacecraft. The comparison shows that the simulation contains the important physical processes that produce the profiles, and confirms that measured changes in the shape and peak wave-length of the hydrogen profiles are the result of changing energy input. This combination of high resolution measurements with modeling provides a method of estimating the incoming energy and changes in flux of precipitating protons over Svalbard, for given energy and pitch-angle distributions. Whereas for electron precipitation, information on the incident particles is derived from brightness and brightness ratios which require at least two spectral windows, for proton precipitation the Doppler profile of resulting hydrogen emission is directly related to the energy and energy flux of the incident energetic protons and can be used to gather information about the source region. As well as the expected Doppler shift to shorter wavelengths, the measured profiles have a significant red-shifted component, the result of upward flowing emitting hydrogen atoms.Key words. Ionosphere (auroral ionosphere; particle precipitation – Magnetospheric physics (auroral phenomena

Collective Thomson scattering measurements with high frequency resolution at TEXTOR

DEFF Research Database (Denmark)

Stejner Pedersen, Morten; Nielsen, Stefan Kragh; Korsholm, Søren Bang

2010-01-01

We discuss the development and first results of a receiver system for the collective Thomson scattering (CTS) diagnostic at TEXTOR with frequency resolution in the megahertz range or better. The improved frequency resolution expands the diagnostic range and utility of CTS measurements in general ...... and is a prerequisite for measurements of ion Bernstein wave signatures in CTS spectra. The first results from the new acquisition system are shown to be consistent with theory and with simultaneous measurements by the standard receiver system. © 2010 EURATOM...

High time resolution measurements of the thermosphere from Fabry-Perot Interferometer measurements of atomic oxygen

Directory of Open Access Journals (Sweden)

E. A. K. Ford

2007-06-01

Full Text Available Recent advances in the performance of CCD detectors have enabled a high time resolution study of the high latitude upper thermosphere with Fabry-Perot Interferometers (FPIs to be performed. 10-s integration times were used during a campaign in April 2004 on an FPI located in northern Sweden in the auroral oval. The FPI is used to study the thermosphere by measuring the oxygen red line emission at 630.0 nm, which emits at an altitude of approximately 240 km. Previous time resolutions have been 4 min at best, due to the cycle of look directions normally observed. By using 10 s rather than 40 s integration times, and by limiting the number of full cycles in a night, high resolution measurements down to 15 s were achievable. This has allowed the maximum variability of the thermospheric winds and temperatures, and 630.0 nm emission intensities, at approximately 240 km, to be determined as a few minutes. This is a significantly greater variability than the often assumed value of 1 h or more. A Lomb-Scargle analysis of this data has shown evidence of gravity wave activity with waves with short periods. Gravity waves are an important feature of mesosphere-lower thermosphere (MLT dynamics, observed using many techniques and providing an important mechanism for energy transfer between atmospheric regions. At high latitudes gravity waves may be generated in-situ by localised auroral activity. Short period waves were detected in all four clear nights when this experiment was performed, in 630.0 nm intensities and thermospheric winds and temperatures. Waves with many periodicities were observed, from periods of several hours, down to 14 min. These waves were seen in all parameters over several nights, implying that this variability is a typical property of the thermosphere.

Remote-controlling chemical reactions by light: towards chemistry with high spatio-temporal resolution.

Science.gov (United States)

Göstl, Robert; Senf, Antti; Hecht, Stefan

2014-03-21

The foundation of the chemical enterprise has always been the creation of new molecular entities, such as pharmaceuticals or polymeric materials. Over the past decades, this continuing effort of designing compounds with improved properties has been complemented by a strong effort to render their preparation (more) sustainable by implementing atom as well as energy economic strategies. Therefore, synthetic chemistry is typically concerned with making specific bonds and connections in a highly selective and efficient manner. However, to increase the degree of sophistication and expand the scope of our work, we argue that the modern aspiring chemist should in addition be concerned with attaining (better) control over when and where chemical bonds are being made or broken. For this purpose, photoswitchable molecular systems, which allow for external modulation of chemical reactions by light, are being developed and in this review we are covering the current state of the art of this exciting new field. These "remote-controlled synthetic tools" provide a remarkable opportunity to perform chemical transformations with high spatial and temporal resolution and should therefore allow regulating biological processes as well as material and device performance.

Application of SSNTDs for measurements of fusion reaction products in high-temperature plasma experiments

Energy Technology Data Exchange (ETDEWEB)

Malinowska, A., E-mail: a.malinowska@ipj.gov.p [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Szydlowski, A.; Malinowski, K. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Sadowski, M.J. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Institute of Plasma Physics and Laser Microfusion (IPPLM), 00-908 Warsaw (Poland); Zebrowski, J. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland); Scholz, M.; Paduch, M.; Zielinska, E. [Institute of Plasma Physics and Laser Microfusion (IPPLM), 00-908 Warsaw (Poland); Jaskola, M.; Korman, A. [Andrzej Soltan Institute for Nuclear Studies (IPJ), 05-400 Otwock-Swierk (Poland)

2009-10-15

The paper describes the application of SSNTDs of the PM-355 type to diagnostics of reaction products emitted from high-temperature deuterium plasmas produced in Plasma Focus (PF) facilities. Acceleration processes occurring in plasma lead often to the generation of high-energy ion beams. Such beams induce nuclear reactions and contribute to the emission of fast neutrons, fusion protons and alpha particles from PF discharges with a deuterium gas. Ion measurements are of primary importance for understanding the mechanisms of the physical processes which drive the charged-particle acceleration. The main aim of the present studies was to perform measurements of spatial- and energy-distributions of fusion-reaction protons (about 3 MeV) within a PF facility. Results obtained from energy measurements were compared with the proton-energy spectra computed theoretically. The protons were measured by means of a set of ion pinhole cameras equipped with PM-355 detectors, which were placed at different angles relative to the electrode axis of the PF facility.

The measurement of the presampled MTF of a high spatial resolution neutron imaging system

International Nuclear Information System (INIS)

Cao, Raymond Lei; Biegalski, Steven R.

2007-01-01

A high spatial resolution neutron imaging device was developed at the Mark II TRIGA reactor at University of Texas at Austin. As the modulation transfer function (MTF) is recognized as a well-established parameter for evaluation of imaging system resolution, the aliasing associated with digital sampling adds complexity to its measurement. Aliasing is especially problematic when using a high spatial resolution micro-channel plate (MCP) neutron detector that has a pixel grid size similar to that of a CCD array. To compensate for the aliasing an angulated edge method was used to evaluate the neutron imaging facility, overcoming aliasing by obtaining an oversampled edge spread function (ESF). Baseline correction was applied to the ESF to remove the noticeable trends and the LSF was multiplied by Hann window to obtain a smoothed version of presampled MTF. The computing procedure is confirmed by visual inspection of a testing phantom; in addition, it is confirmed by comparison to the MTF measurement of a scintillation screen with a known MTF curve

Fission fragment yields from heavy-ion-induced reactions measured with a fragment separator

Science.gov (United States)

Tarasov, O. B.; Delaune, O.; Farget, F.; Morrissey, D. J.; Amthor, A. M.; Bastin, B.; Bazin, D.; Blank, B.; Cacéres, L.; Chbihi, A.; Fernández-Dominguez, B.; Grévy, S.; Kamalou, O.; Lukyanov, S. M.; Mittig, W.; Pereira, J.; Perrot, L.; Saint-Laurent, M.-G.; Savajols, H.; Sherrill, B. M.; Stodel, C.; Thomas, J. C.; Villari, A. C.

2018-04-01

The systematic study of fission fragment yields under different initial conditions has provided valuable experimental data for benchmarking models of fission product yields. Nuclear reactions using inverse kinematics coupled to the use of a high-resolution spectrometer with good fragment identification are shown here to be a powerful tool to measure the inclusive isotopic yields of fission fragments. In-flight fusion-fission was used in this work to produce secondary beams of neutron-rich isotopes in the collisions of a 238U beam at 24 MeV/u with 9Be and 12C targets at GANIL using the LISE3 fragment separator. Unique identification of the A, Z, and atomic charge state, q, of fission products was attained with the Δ E- TKE-B ρ- ToF measurement technique. Mass, and atomic number distributions are reported for the two reactions. The results show the importance of different reaction mechanisms in the two cases. The optimal target material for higher yields of neutron-rich high- Z isotopes produced in fusion-fission reactions as a function of projectile energy is discussed.

High resolution resonance studies with the (p,p) and (p,α) reactions

International Nuclear Information System (INIS)

Bilpuch, E.G.; Mitchell, G.E.; Brooks, W.

1985-01-01

Recently the authors have extended their high resolution studies to targets with spin. A series of measurements on non-zero spin targets in the 2s-1d shell is now in progress. In section b the analysis of resonance data for targets with spin is described, with emphasis on s and l mixing. In sections c and d the authors briefly summarize the published data on 27 Al and 25 Mg, while in sections e, f, and g preliminary results for 33 S, 39 K, and 23 Na are described. The relevance of the entrance channel relative phase to a class of parity mixing experiments is discussed in section h

High-Resolution Energy and Intensity Measurements with CVD Diamond at REX-ISOLDE

CERN Document Server

Griesmayer, E; Dobos, D; Wenander, F; Bergoz, J; Bayle, H; Frais-Kölbl, H; Leinweber, J; Aumeyr, T; CERN. Geneva. BE Department

2009-01-01

A novel beam instrumentation device for the HIE-REX (High In-tensity and Energy REX) upgrade has been developed and tested at the On-Line Isotope Mass Separator ISOLDE, located at the European Laboratory for Particle Physics (CERN). This device is based on CVD diamond detector technology and is used for measuring the beam intensity, particle counting and measuring the energy spectrum of the beam. An energy resolution of 0.6% was measured at a carbon ion energy of 22.8 MeV. This corresponds to an energy spread of ± 140 keV.

Low-cost, portable, robust and high-resolution single-camera stereo-DIC system and its application in high-temperature deformation measurements

Science.gov (United States)

Chi, Yuxi; Yu, Liping; Pan, Bing

2018-05-01

A low-cost, portable, robust and high-resolution single-camera stereo-digital image correlation (stereo-DIC) system for accurate surface three-dimensional (3D) shape and deformation measurements is described. This system adopts a single consumer-grade high-resolution digital Single Lens Reflex (SLR) camera and a four-mirror adaptor, rather than two synchronized industrial digital cameras, for stereo image acquisition. In addition, monochromatic blue light illumination and coupled bandpass filter imaging are integrated to ensure the robustness of the system against ambient light variations. In contrast to conventional binocular stereo-DIC systems, the developed pseudo-stereo-DIC system offers the advantages of low cost, portability, robustness against ambient light variations, and high resolution. The accuracy and precision of the developed single SLR camera-based stereo-DIC system were validated by measuring the 3D shape of a stationary sphere along with in-plane and out-of-plane displacements of a translated planar plate. Application of the established system to thermal deformation measurement of an alumina ceramic plate and a stainless-steel plate subjected to radiation heating was also demonstrated.

High-resolution noise substitution to measure overfitting and validate resolution in 3D structure determination by single particle electron cryomicroscopy

International Nuclear Information System (INIS)

Chen, Shaoxia; McMullan, Greg; Faruqi, Abdul R.; Murshudov, Garib N.; Short, Judith M.; Scheres, Sjors H.W.; Henderson, Richard

2013-01-01

Three-dimensional (3D) structure determination by single particle electron cryomicroscopy (cryoEM) involves the calculation of an initial 3D model, followed by extensive iterative improvement of the orientation determination of the individual particle images and the resulting 3D map. Because there is much more noise than signal at high resolution in the images, this creates the possibility of noise reinforcement in the 3D map, which can give a false impression of the resolution attained. The balance between signal and noise in the final map at its limiting resolution depends on the image processing procedure and is not easily predicted. There is a growing awareness in the cryoEM community of how to avoid such over-fitting and over-estimation of resolution. Equally, there has been a reluctance to use the two principal methods of avoidance because they give lower resolution estimates, which some people believe are too pessimistic. Here we describe a simple test that is compatible with any image processing protocol. The test allows measurement of the amount of signal and the amount of noise from overfitting that is present in the final 3D map. We have applied the method to two different sets of cryoEM images of the enzyme beta-galactosidase using several image processing packages. Our procedure involves substituting the Fourier components of the initial particle image stack beyond a chosen resolution by either the Fourier components from an adjacent area of background, or by simple randomisation of the phases of the particle structure factors. This substituted noise thus has the same spectral power distribution as the original data. Comparison of the Fourier Shell Correlation (FSC) plots from the 3D map obtained using the experimental data with that from the same data with high-resolution noise (HR-noise) substituted allows an unambiguous measurement of the amount of overfitting and an accompanying resolution assessment. A simple formula can be used to calculate an

High-resolution noise substitution to measure overfitting and validate resolution in 3D structure determination by single particle electron cryomicroscopy

Energy Technology Data Exchange (ETDEWEB)

Chen, Shaoxia; McMullan, Greg; Faruqi, Abdul R.; Murshudov, Garib N.; Short, Judith M.; Scheres, Sjors H.W.; Henderson, Richard, E-mail: rh15@mrc-lmb.cam.ac.uk

2013-12-15

Three-dimensional (3D) structure determination by single particle electron cryomicroscopy (cryoEM) involves the calculation of an initial 3D model, followed by extensive iterative improvement of the orientation determination of the individual particle images and the resulting 3D map. Because there is much more noise than signal at high resolution in the images, this creates the possibility of noise reinforcement in the 3D map, which can give a false impression of the resolution attained. The balance between signal and noise in the final map at its limiting resolution depends on the image processing procedure and is not easily predicted. There is a growing awareness in the cryoEM community of how to avoid such over-fitting and over-estimation of resolution. Equally, there has been a reluctance to use the two principal methods of avoidance because they give lower resolution estimates, which some people believe are too pessimistic. Here we describe a simple test that is compatible with any image processing protocol. The test allows measurement of the amount of signal and the amount of noise from overfitting that is present in the final 3D map. We have applied the method to two different sets of cryoEM images of the enzyme beta-galactosidase using several image processing packages. Our procedure involves substituting the Fourier components of the initial particle image stack beyond a chosen resolution by either the Fourier components from an adjacent area of background, or by simple randomisation of the phases of the particle structure factors. This substituted noise thus has the same spectral power distribution as the original data. Comparison of the Fourier Shell Correlation (FSC) plots from the 3D map obtained using the experimental data with that from the same data with high-resolution noise (HR-noise) substituted allows an unambiguous measurement of the amount of overfitting and an accompanying resolution assessment. A simple formula can be used to calculate an

Fall speed measurement and high-resolution multi-angle photography of hydrometeors in free fall

OpenAIRE

T. J. Garrett; C. Fallgatter; K. Shkurko; D. Howlett

2012-01-01

We describe here a new instrument for imaging hydrometeors in free fall. The Multi-Angle Snowflake Camera (MASC) captures high-resolution photographs of hydrometeors from three angles while simultaneously measuring their fall speed. Based on the stereoscopic photographs captured over the two months of continuous measurements obtained at a high altitude location within the Wasatch Front in Utah, we derive statistics for fall speed, hydrometeor size, shape, orientation and asp...

High resolution 148Nd(3He, ny) two proton stripping reaction and the structure of the O2+ state in 150Sm

International Nuclear Information System (INIS)

Sharpey-Schafer, J.F.; Dinoko, T.S.; Herbert, M.S.; Orce, J.N.; Papka, P.; Kheswa, B.V.; Ndayishimye, J.; Bvumbi, S.P.; Jones, P.M.; Bucher, T.D.; Lawrie, E.A.; Lawrie, J.J.; Negi, D.; Shirinda, O.; Wiedeking, M.; Vymers, P.; Easton, J.L.; Noncolela, S.P.; Sithole, P.; Khumalo, N.; Majola, S.N.T.; Stankiewicz, M.A.

2014-01-01

The challenge of achieving high resolution in binary reactions involving an outgoing high energy neutron is solved by detecting the γ-ray decay of populated excited states in an array of escape suppressed HPGe detectors in coincidence with fast neutrons detected in a wall of scintillator detectors 2 m down beam of the target. The selectivity of the arrangement is of the order of 1 in 1000. The time-of-flight difference is sufficient to separate fast neutrons from direct reactions from a large background of statistical neutrons from fusion-evaporation reactions. Our interest is in the wavefunction of the 0 2 + state at 740 keV in the N=88 nucleus 150 Sm which, with the 0 2 + state in 100 Ru, are the only two excited states observed in 2β2ν double β-decay. (authors)

Kinematical coincidence method in transfer reactions

Energy Technology Data Exchange (ETDEWEB)

Acosta, L.; Amorini, F. [INFN—Laboratori Nazionali del Sud, Via S. Sofia, Catania (Italy); Auditore, L. [INFN Gruppo Collegato di Messina and Dipartimento di Fisica, Università di Messina (Italy); Berceanu, I. [Institute for Physics and Nuclear Engineering, Bucharest (Romania); Cardella, G., E-mail: cardella@ct.infn.it [INFN—Sezione di Catania, Via S. Sofia, 95123 Catania (Italy); Chatterjiee, M.B. [Saha Institute for Nuclear Physics, Kolkata (India); De Filippo, E. [INFN—Sezione di Catania, Via S. Sofia, 95123 Catania (Italy); Francalanza, L.; Gianì, R. [INFN—Laboratori Nazionali del Sud, Via S. Sofia, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia, Catania (Italy); Grassi, L. [INFN—Sezione di Catania, Via S. Sofia, 95123 Catania (Italy); Rudjer Boskovic Institute, Zagreb (Croatia); Grzeszczuk, A. [Institut of Physics, University of Silesia, Katowice (Poland); La Guidara, E. [INFN—Sezione di Catania, Via S. Sofia, 95123 Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Lanzalone, G. [INFN—Laboratori Nazionali del Sud, Via S. Sofia, Catania (Italy); Facoltà di Ingegneria e Architettura, Università Kore, Enna (Italy); Lombardo, I. [INFN—Laboratori Nazionali del Sud, Via S. Sofia, Catania (Italy); Dipartimento di Scienze Fisiche, Università Federico II and INFN Sezione di Napoli (Italy); Loria, D.; Minniti, T. [INFN Gruppo Collegato di Messina and Dipartimento di Fisica, Università di Messina (Italy); Pagano, E.V. [INFN—Laboratori Nazionali del Sud, Via S. Sofia, Catania (Italy); Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia, Catania (Italy); and others

2013-07-01

A new method to extract high resolution angular distributions from kinematical coincidence measurements in binary reactions is presented. Kinematics is used to extract the center of mass angular distribution from the measured energy spectrum of light particles. Results obtained in the case of {sup 10}Be+p→{sup 9}Be+d reaction measured with the CHIMERA detector are shown. An angular resolution of few degrees in the center of mass is obtained. The range of applicability of the method is discussed.

Measuring high-resolution sky luminance distributions with a CCD camera.

Science.gov (United States)

Tohsing, Korntip; Schrempf, Michael; Riechelmann, Stefan; Schilke, Holger; Seckmeyer, Gunther

2013-03-10

We describe how sky luminance can be derived from a newly developed hemispherical sky imager (HSI) system. The system contains a commercial compact charge coupled device (CCD) camera equipped with a fish-eye lens. The projection of the camera system has been found to be nearly equidistant. The luminance from the high dynamic range images has been calculated and then validated with luminance data measured by a CCD array spectroradiometer. The deviation between both datasets is less than 10% for cloudless and completely overcast skies, and differs by no more than 20% for all sky conditions. The global illuminance derived from the HSI pictures deviates by less than 5% and 20% under cloudless and cloudy skies for solar zenith angles less than 80°, respectively. This system is therefore capable of measuring sky luminance with the high spatial and temporal resolution of more than a million pixels and every 20 s respectively.

Direct Measurements of Half-Cycle Reaction Heats during Atomic Layer Deposition by Calorimetry

Energy Technology Data Exchange (ETDEWEB)

Lownsbury, James M. [Department; Gladden, James A. [Department; Campbell, Charles T. [Department; Department; Kim, In Soo [Materials; Martinson, Alex B. F. [Materials

2017-10-05

We introduce a new high-temperature adsorption calorimeter that approaches the ideal limit of a heat detector whereby the signal at any time is proportional to the heat power being delivered to the sample and prove its sensitivity for measuring pulse-to-pulse heats of half-reactions during atomic layer deposition (ALD) at 400 K. The heat dynamics of amorphous Al2O3 growth via sequential self-limiting surface reaction of trimethylaluminum (TMA) and H2O is clearly resolved. Calibration enables quantitation of the exothermic TMA and H2O half-reactions with high precision, -343 kJ/mol TMA and -251 kJ/mol H2O, respectively. A time resolution better than 1 ms is demonstrated, allowing for the deconvolution of at least two distinct surface reactions during TMA microdosing. It is further demonstrated that this method can provide the heat of reaction versus extent of reaction during each precursors half-reaction, thus providing even richer mechanistic information on the surface processes involved. The broad applicability of this novel calorimeter is demonstrated through excellent signal-to-noise ratios of less exothermic ALD half-reactions to produce TiO2 and MnO.

High resolution (transformers.

Science.gov (United States)

Garcia-Souto, Jose A; Lamela-Rivera, Horacio

2006-10-16

A novel fiber-optic interferometric sensor is presented for vibrations measurements and analysis. In this approach, it is shown applied to the vibrations of electrical structures within power transformers. A main feature of the sensor is that an unambiguous optical phase measurement is performed using the direct detection of the interferometer output, without external modulation, for a more compact and stable implementation. High resolution of the interferometric measurement is obtained with this technique (transformers are also highlighted.

The Palladium-Catalyzed Aerobic Kinetic Resolution of Secondary Alcohols: Reaction Development, Scope, and Applications

KAUST Repository

Ebner, Davidâ C.; Bagdanoff, Jeffreyâ T.; Ferreira, Ericâ M.; McFadden, Ryanâ M.; Caspi, Danielâ D.; Trend, Raissaâ M.; Stoltz, Brianâ M.

2009-01-01

The first palladium-catalyzed enantioselective oxidation of secondary alcohols has been developed, utilizing the readily available diamine (-)-sparteine as a chiral ligand and molecular oxygen as the stoichiometric oxidant. Mechanistic insights regarding the role of the base and hydrogen-bond donors have resulted in several improvements to the original system. Namely, addition of cesium carbonate and tert-butyl alcohol greatly enhances reaction rates, promoting rapid resolutions. The use of chloroform as solvent allows the use of ambient air as the terminal oxidant at 23 degrees C, resulting in enhanced catalyst selectivity. These improved reaction conditions have permitted the successful kinetic resolution of benzylic, allylic, and cyclopropyl secondary alcohols to high enantiomeric excess with good-to-excellent selectivity factors. This catalyst system has also been applied to the desymmetrization of meso-diols, providing high yields of enantioenriched hydroxyketones.

The Palladium-Catalyzed Aerobic Kinetic Resolution of Secondary Alcohols: Reaction Development, Scope, and Applications

KAUST Repository

Ebner, Davidâ C.

2009-12-07

The first palladium-catalyzed enantioselective oxidation of secondary alcohols has been developed, utilizing the readily available diamine (-)-sparteine as a chiral ligand and molecular oxygen as the stoichiometric oxidant. Mechanistic insights regarding the role of the base and hydrogen-bond donors have resulted in several improvements to the original system. Namely, addition of cesium carbonate and tert-butyl alcohol greatly enhances reaction rates, promoting rapid resolutions. The use of chloroform as solvent allows the use of ambient air as the terminal oxidant at 23 degrees C, resulting in enhanced catalyst selectivity. These improved reaction conditions have permitted the successful kinetic resolution of benzylic, allylic, and cyclopropyl secondary alcohols to high enantiomeric excess with good-to-excellent selectivity factors. This catalyst system has also been applied to the desymmetrization of meso-diols, providing high yields of enantioenriched hydroxyketones.

Accurate Mass Measurements for Planetary Microlensing Events Using High Angular Resolution Observations

Directory of Open Access Journals (Sweden)

Jean-Philippe Beaulieu

2018-04-01

Full Text Available The microlensing technique is a unique method to hunt for cold planets over a range of mass and separation, orbiting all varieties of host stars in the disk of our galaxy. It provides precise mass-ratio and projected separations in units of the Einstein ring radius. In order to obtain the physical parameters (mass, distance, orbital separation of the system, it is necessary to combine the result of light curve modeling with lens mass-distance relations and/or perform a Bayesian analysis with a galactic model. A first mass-distance relation could be obtained from a constraint on the Einstein ring radius if the crossing time of the source over the caustic is measured. It could then be supplemented by secondary constraints such as parallax measurements, ideally by using coinciding ground and space-born observations. These are still subject to degeneracies, like the orbital motion of the lens. A third mass-distance relation can be obtained thanks to constraints on the lens luminosity using high angular resolution observations with 8 m class telescopes or the Hubble Space Telescope. The latter route, although quite inexpensive in telescope time is very effective. If we have to rely heavily on Bayesian analysis and limited constraints on mass-distance relations, the physical parameters are determined to 30–40% typically. In a handful of cases, ground-space parallax is a powerful route to get stronger constraint on masses. High angular resolution observations will be able to constrain the luminosity of the lenses in the majority of the cases, and in favorable circumstances it is possible to derive physical parameters to 10% or better. Moreover, these constraints will be obtained in most of the planets to be discovered by the Euclid and WFIRST satellites. We describe here the state-of-the-art approaches to measure lens masses and distances with an emphasis on high angular resolution observations. We will discuss the challenges, recent results and

Scatterings and reactions by means of polarized neutron beam

International Nuclear Information System (INIS)

Koori, N.

1989-01-01

A high resolution polarized neutron beam should be prepared for nuclear physics, which will be planned with the new ring cyclotron at RCNP. Studies on scatterings and reactions by means of polarized neutron beams are reviewed briefly. Beam lines for polarized neutrons are summarized. An example of high resolution measurements of neutron induced reactions is described. (author)

High-Resolution Measurements of Low-Energy Conversion Electrons

CERN Multimedia

Gizon, A; Putaux, J

2002-01-01

Measurements of low-energy internal conversion electrons have been performed with high energy resolution in some N = 105 odd and odd-odd nuclei using a semi-circular spectrograph associated to a specific tape transport system. These experiments aimed to answer the following questions~: \\begin{itemize} \\item Do M3 isomeric transitions exist in $^{183}$Pt and $^{181}$Os, isotones of $^{184}$Au~? \\item Are the neutron configurations proposed to describe the isomeric and ground states of $^{184}$Au right or wrong~? \\item Does it exist an isomeric state in $^{182}$Ir, isotone of $^{181}$Os, $^{183}$Pt and $^{184}$Au~? \\item What are the spin and parity values of the excited states of $^{182}$Ir~? \\end{itemize} In $^{183}$Pt, the 35.0 keV M3 isomeric transition has been clearly observed and the reduced transition probability has been determined. The deduced hindrance factor is close to that observed in the neighbouring odd-odd $^{184}$Au nucleus. This confirms the neutron configurations previously proposed for the ...

Development of high time-resolution laser flash equipment for thermal diffusivity measurements using miniature-size specimens

International Nuclear Information System (INIS)

Shikama, Tatsuo; Namba, Chusei; Kosuda, Michinori; Maeda, Yukio.

1994-01-01

For measurements of thermal diffusivity of miniature-size specimens heavily irradiated by neutrons, a new Q-switched laser-flash instrument was developed. In the present instrument the time-resolution was improved to 0.1 ms by using a laser-pulse width of 25 ns. The realization of high time-resolution made it possible to measure the thermal diffusivity of thin specimens. It is expected that copper of 0.7 mm thick, and SUS 304 of 0.1 mm could be used for the measurements. In case of ATJ graphite, 0.5 mm thick specimen could be used for the reliable measurement in the temperature range of 300-1300 K. (author)

Performance monitoring and response conflict resolution associated with choice stepping reaction tasks.

Science.gov (United States)

Watanabe, Tatsunori; Tsutou, Kotaro; Saito, Kotaro; Ishida, Kazuto; Tanabe, Shigeo; Nojima, Ippei

2016-11-01

Choice reaction requires response conflict resolution, and the resolution processes that occur during a choice stepping reaction task undertaken in a standing position, which requires maintenance of balance, may be different to those processes occurring during a choice reaction task performed in a seated position. The study purpose was to investigate the resolution processes during a choice stepping reaction task at the cortical level using electroencephalography and compare the results with a control task involving ankle dorsiflexion responses. Twelve young adults either stepped forward or dorsiflexed the ankle in response to a visual imperative stimulus presented on a computer screen. We used the Simon task and examined the error-related negativity (ERN) that follows an incorrect response and the correct-response negativity (CRN) that follows a correct response. Error was defined as an incorrect initial weight transfer for the stepping task and as an incorrect initial tibialis anterior activation for the control task. Results revealed that ERN and CRN amplitudes were similar in size for the stepping task, whereas the amplitude of ERN was larger than that of CRN for the control task. The ERN amplitude was also larger in the stepping task than the control task. These observations suggest that a choice stepping reaction task involves a strategy emphasizing post-response conflict and general performance monitoring of actual and required responses and also requires greater cognitive load than a choice dorsiflexion reaction. The response conflict resolution processes appear to be different for stepping tasks and reaction tasks performed in a seated position.

Near-optimum procedure for half-life measurement by high-resolution gamma-ray spectrometry

International Nuclear Information System (INIS)

Parker, J.L.

1989-01-01

A near-optimum procedure for using high-resolution γ-ray spectrometry to measure the half-lives of appropriate γ-ray- emitting-nuclides is presented. Among the important points of the procedure are the employment of the reference source method for implicit correction of pileup and deadtime losses; the use of full-energy peak-area ratios as the fundamental measured quantities; and continuous, high-rate data acquisition to obtain good results in a fraction of a half-life if desired. Equations are given for estimating the precision of the computed half-lives in terms of total measurement time, number of spectral acquisitions, and the precision of peak-area ratios. Results of 169 Yb half-life measurements are given as an example of the procedure's application. 3 refs., 2 tabs

Quantitative and Selective Analysis of Feline Growth Related Proteins Using Parallel Reaction Monitoring High Resolution Mass Spectrometry.

Directory of Open Access Journals (Sweden)

Mårten Sundberg

Full Text Available Today immunoassays are widely used in veterinary medicine, but lack of species specific assays often necessitates the use of assays developed for human applications. Mass spectrometry (MS is an attractive alternative due to high specificity and versatility, allowing for species-independent analysis. Targeted MS-based quantification methods are valuable complements to large scale shotgun analysis. A method referred to as parallel reaction monitoring (PRM, implemented on Orbitrap MS, has lately been presented as an excellent alternative to more traditional selected reaction monitoring/multiple reaction monitoring (SRM/MRM methods. The insulin-like growth factor (IGF-system is not well described in the cat but there are indications of important differences between cats and humans. In feline medicine IGF-I is mainly analyzed for diagnosis of growth hormone disorders but also for research, while the other proteins in the IGF-system are not routinely analyzed within clinical practice. Here, a PRM method for quantification of IGF-I, IGF-II, IGF binding protein (BP -3 and IGFBP-5 in feline serum is presented. Selective quantification was supported by the use of a newly launched internal standard named QPrEST™. Homology searches demonstrated the possibility to use this standard of human origin for quantification of the targeted feline proteins. Excellent quantitative sensitivity at the attomol/μL (pM level and selectivity were obtained. As the presented approach is very generic we show that high resolution mass spectrometry in combination with PRM and QPrEST™ internal standards is a versatile tool for protein quantitation across multispecies.

High resolution photoelectron spectroscopy

International Nuclear Information System (INIS)

Arko, A.J.

1988-01-01

Photoelectron Spectroscopy (PES) covers a very broad range of measurements, disciplines, and interests. As the next generation light source, the FEL will result in improvements over the undulator that are larger than the undulater improvements over bending magnets. The combination of high flux and high inherent resolution will result in several orders of magnitude gain in signal to noise over measurements using synchrotron-based undulators. The latter still require monochromators. Their resolution is invariably strongly energy-dependent so that in the regions of interest for many experiments (h upsilon > 100 eV) they will not have a resolving power much over 1000. In order to study some of the interesting phenomena in actinides (heavy fermions e.g.) one would need resolving powers of 10 4 to 10 5 . These values are only reachable with the FEL

High-Resolution Sonars: What Resolution Do We Need for Target Recognition?

Directory of Open Access Journals (Sweden)

Pailhas Yan

2010-01-01

Full Text Available Target recognition in sonar imagery has long been an active research area in the maritime domain, especially in the mine-counter measure context. Recently it has received even more attention as new sensors with increased resolution have been developed; new threats to critical maritime assets and a new paradigm for target recognition based on autonomous platforms have emerged. With the recent introduction of Synthetic Aperture Sonar systems and high-frequency sonars, sonar resolution has dramatically increased and noise levels decreased. Sonar images are distance images but at high resolution they tend to appear visually as optical images. Traditionally algorithms have been developed specifically for imaging sonars because of their limited resolution and high noise levels. With high-resolution sonars, algorithms developed in the image processing field for natural images become applicable. However, the lack of large datasets has hampered the development of such algorithms. Here we present a fast and realistic sonar simulator enabling development and evaluation of such algorithms.We develop a classifier and then analyse its performances using our simulated synthetic sonar images. Finally, we discuss sensor resolution requirements to achieve effective classification of various targets and demonstrate that with high resolution sonars target highlight analysis is the key for target recognition.

Energetics of small scale turbulence in the lower stratosphere from high resolution radar measurements

Directory of Open Access Journals (Sweden)

J. Dole

2001-08-01

Full Text Available Very high resolution radar measurements were performed in the troposphere and lower stratosphere by means of the PROUST radar. The PROUST radar operates in the UHF band (961 MHz and is located in St. Santin, France (44°39’ N, 2°12’ E. A field campaign involving high resolution balloon measurements and the PROUST radar was conducted during April 1998. Under the classical hypothesis that refractive index inhomogeneities at half radar wavelength lie within the inertial subrange, assumed to be isotropic, kinetic energy and temperature variance dissipation rates were estimated independently in the lower stratosphere. The dissipation rate of temperature variance is proportional to the dissipation rate of available potential energy. We therefore estimate the ratio of dissipation rates of potential to kinetic energy. This ratio is a key parameter of atmospheric turbulence which, in locally homogeneous and stationary conditions, is simply related to the flux Richardson number, Rf .Key words. Meteorology and atmospheric dynamics (turbulence – Radio science (remote sensing

High-resolution investigation of the 35Cl(d, p)36Cl reaction

NARCIS (Netherlands)

Decowski, P.

1971-01-01

The angular distributions of 15 proton groups from the 35C1(d, p)36C1 reaction have been measured with a split-pole magnetic spectrograph at Ed = 7 MeV. The 36C1 doublet at 1.95 MeV could be resolved in the angular distribution measurements. A DWBA analysis yields l-values and spectroscopic factors.

HIGH-TIME-RESOLUTION MEASUREMENTS OF THE POLARIZATION OF THE CRAB PULSAR AT 1.38 GHz

Energy Technology Data Exchange (ETDEWEB)

Słowikowska, Agnieszka [Kepler Institute of Astronomy, University of Zielona Góra, Lubuska 2, 65-265 Zielona Góra (Poland); Stappers, Benjamin W. [Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester M13 9PL (United Kingdom); Harding, Alice K. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); O' Dell, Stephen L.; Elsner, Ronald F.; Weisskopf, Martin C. [Astrophysics Office, NASA Marshall Space Flight Center, ZP12, Huntsville, AL 35812 (United States); Van der Horst, Alexander J. [Astronomical Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)

2015-01-20

Using the Westerbork Synthesis Radio Telescope, we obtained high-time-resolution measurements of the full polarization of the Crab pulsar. At a resolution of 1/8192 of the 34 ms pulse period (i.e., 4.1 μs), the 1.38 GHz linear-polarization measurements are in general agreement with previous lower-time-resolution 1.4 GHz measurements of linear polarization in the main pulse (MP), in the interpulse (IP), and in the low-frequency component (LFC). We find the MP and IP to be linearly polarized at about 24% and 21% with no discernible difference in polarization position angle. However, contrary to theoretical expectations and measurements in the visible, we find no evidence for significant variation (sweep) in the polarization position angle over the MP, the IP, or the LFC. We discuss the implications, which appear to be in contradiction to theoretical expectations. We also detect weak circular polarization in the MP and IP, and strong (≈20%) circular polarization in the LFC, which also exhibits very strong (≈98%) linear polarization at a position angle of 40° from that of the MP or IP. The properties are consistent with the LFC, which is a low-altitude component, and the MP and IP, which are high-altitude caustic components. Current models for the MP and IP emission do not readily account for the absence of pronounced polarization changes across the pulse. We measure IP and LFC pulse phases relative to the MP consistent with recent measurements, which have shown that the phases of these pulse components are evolving with time.

High-resolution spectroscopy of gases for industrial applications

DEFF Research Database (Denmark)

Fateev, Alexander; Clausen, Sønnik

High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing...... databases (e.g. HITRAN, HITEMP or CDSD) can normally be used for absorption spectra calculations at limited temperature/pressure ranges. Therefore experimental measurements of absorption/transmission spectra gases (e.g. CO2, H2O or SO2) at high-resolution and elevated temperatures are essential both...... for analysis of complex experimental data and further development of the databases. High-temperature gas cell facilities available at DTU Chemical Engineering are presented and described. The gas cells and high-resolution spectrometers allow us to perform high-quality reference measurements of gases relevant...

A compact PTR-ToF-MS instrument for airborne measurements of volatile organic compounds at high spatiotemporal resolution

Directory of Open Access Journals (Sweden)

M. Müller

2014-11-01

Full Text Available Herein, we report on the development of a compact proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS for airborne measurements of volatile organic compounds (VOCs. The new instrument resolves isobaric ions with a mass resolving power (m/Δm of ~1000, provides accurate m/z measurements (Δm < 3 mDa, records full mass spectra at 1 Hz and thus overcomes some of the major analytical deficiencies of quadrupole-MS-based airborne instruments. 1 Hz detection limits for biogenic VOCs (isoprene, α total monoterpenes, aromatic VOCs (benzene, toluene, xylenes and ketones (acetone, methyl ethyl ketone range from 0.05 to 0.12 ppbV, making the instrument well-suited for fast measurements of abundant VOCs in the continental boundary layer. The instrument detects and quantifies VOCs in locally confined plumes (< 1 km, which improves our capability of characterizing emission sources and atmospheric processing within plumes. A deployment during the NASA 2013 DISCOVER-AQ mission generated high vertical- and horizontal-resolution in situ data of VOCs and ammonia for the validation of satellite retrievals and chemistry transport models.

Potassium Stable Isotopic Compositions Measured by High-Resolution MC-ICP-MS

Science.gov (United States)

Morgan, Leah E.; Lloyd, Nicholas S.; Ellam, Robert M.; Simon, Justin I.

2012-01-01

Potassium isotopic (K-41/K-39) compositions are notoriously difficult to measure. TIMS measurements are hindered by variable fractionation patterns throughout individual runs and too few isotopes to apply an internal spike method for instrumental mass fractionation corrections. Internal fractionation corrections via the K-40/K-39 ratio can provide precise values but assume identical K-40/K-39 ratios (e.g. 0.05% (1sigma) in [1]); this is appropriate in some cases (e.g. identifying excess K-41) but not others (e.g., determining mass fractionation effects and metrologically traceable isotopic abundances). SIMS analyses have yielded measurements with 0.25% precisions (1sigma) [2]. ICP-MS analyses are significantly affected by interferences from molecular species such as Ar-38H(+) and Ar-40H(+) and instrument mass bias. Single collector ICP-MS instruments in "cold plasma" mode have yielded uncertainties as low as 2% (1sigma, e.g. [3]). Although these precisions may be acceptable for some concentration determinations, they do not resolve isotopic variation in terrestrial materials. Here we present data from a series of measurements made on the Thermo Scientific NEPTUNE Plus multi-collector ICP-MS that demonstrate the ability to make K-41/K-39 ratio measurements with 0.07% precisions (1sigma). These data, collected on NIST K standards, indicate the potential for MC-ICP-MS measurements to look for K isotopic variations at the sub-permil level. The NEPTUNE Plus can sufficiently resolve 39K and 41K from the interfering 38ArH+ and 40ArH+ peaks in wet cold plasma and high-resolution mode. Measurements were made on small but flat, interference-free, plateaus (ca. 50 ppm by mass width for K-41). Although ICP-MS does not yield accurate K-41/K-39 values due to significant instrumental mass fractionation (ca. 6%), this bias can be sufficiently stable over the time required for several measurements so that relative K-41/K-39 values can be precisely determined via sample

Electrochemistry-High Resolution Mass Spectrometry to Study Oxidation Products of Trimethoprim

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Marc-André Lecours

2018-01-01

Full Text Available The study of the fate of emerging organic contaminants (EOCs, especially the identification of transformation products, after water treatment or in the aquatic environment, is a topic of growing interest. In recent years, electrochemistry coupled to mass spectrometry has attracted a lot of attention as an alternative technique to investigate oxidation metabolites of organic compounds. The present study used different electrochemical approaches, such as cyclic voltammetry, electrolysis, electro-assisted Fenton reaction coupled offline to high resolution mass spectrometry and thin-layer flow cell coupled online to high resolution mass spectrometry, to study oxidation products of the anti-infective trimethoprim, a contaminant of emerging concern frequently reported in wastewaters and surface waters. Results showed that mono- and di-hydroxylated derivatives of trimethoprim were generated in electrochemically and possibly tri-hydroxylated derivatives as well. Those compounds have been previously reported as mammalian and bacterial metabolites as well as transformation products of advance oxidation processes applied to waters containing trimethoprim. Therefore, this study confirmed that electrochemical techniques are relevant not only to mimic specific biotransformation reactions of organic contaminants, as it has been suggested previously, but also to study the oxidation reactions of organic contaminants of interest in water treatment. The key role that redox reactions play in the environment make electrochemistry-high resolution mass spectrometry a sensitive and simple technique to improve our understanding of the fate of organic contaminants in the environment.

Marvel Analysis of the Measured High-resolution Rovibronic Spectra of TiO

Science.gov (United States)

McKemmish, Laura K.; Masseron, Thomas; Sheppard, Samuel; Sandeman, Elizabeth; Schofield, Zak; Furtenbacher, Tibor; Császár, Attila G.; Tennyson, Jonathan; Sousa-Silva, Clara

2017-02-01

Accurate, experimental rovibronic energy levels, with associated labels and uncertainties, are reported for 11 low-lying electronic states of the diatomic {}48{{Ti}}16{{O}} molecule, determined using the Marvel (Measured Active Rotational-Vibrational Energy Levels) algorithm. All levels are based on lines corresponding to critically reviewed and validated high-resolution experimental spectra taken from 24 literature sources. The transition data are in the 2-22,160 cm-1 region. Out of the 49,679 measured transitions, 43,885 are triplet-triplet, 5710 are singlet-singlet, and 84 are triplet-singlet transitions. A careful analysis of the resulting experimental spectroscopic network (SN) allows 48,590 transitions to be validated. The transitions determine 93 vibrational band origins of {}48{{Ti}}16{{O}}, including 71 triplet and 22 singlet ones. There are 276 (73) triplet-triplet (singlet-singlet) band-heads derived from Marvel experimental energies, 123(38) of which have never been assigned in low- or high-resolution experiments. The highest J value, where J stands for the total angular momentum, for which an energy level is validated is 163. The number of experimentally derived triplet and singlet {}48{{Ti}}16{{O}} rovibrational energy levels is 8682 and 1882, respectively. The lists of validated lines and levels for {}48{{Ti}}16{{O}} are deposited in the supporting information to this paper.

The investigation of active Martian dune fields using very high resolution photogrammetric measurements

Science.gov (United States)

Kim, Jungrack; Kim, Younghwi; Park, Minseong

2016-10-01

At the present time, arguments continue regarding the migration speeds of Martian dune fields and their correlation with atmospheric circulation. However, precisely measuring the spatial translation of Martian dunes has succeeded only a very few times—for example, in the Nili Patera study (Bridges et al. 2012) using change-detection algorithms and orbital imagery. Therefore, in this study, we developed a generic procedure to precisely measure the migration of dune fields with recently introduced 25-cm resolution orbital imagery specifically using a high-accuracy photogrammetric processor. The processor was designed to trace estimated dune migration, albeit slight, over the Martian surface by 1) the introduction of very high resolution ortho images and stereo analysis based on hierarchical geodetic control for better initial point settings; 2) positioning error removal throughout the sensor model refinement with a non-rigorous bundle block adjustment, which makes possible the co-alignment of all images in a time series; and 3) improved sub-pixel co-registration algorithms using optical flow with a refinement stage conducted on a pyramidal grid processor and a blunder classifier. Moreover, volumetric changes of Martian dunes were additionally traced by means of stereo analysis and photoclinometry. The established algorithms have been tested using high-resolution HIRISE time-series images over several Martian dune fields. Dune migrations were iteratively processed both spatially and volumetrically, and the results were integrated to be compared to the Martian climate model. Migrations over well-known crater dune fields appeared to be almost static for the considerable temporal periods and were weakly correlated with wind directions estimated by the Mars Climate Database (Millour et al. 2015). As a result, a number of measurements over dune fields in the Mars Global Dune Database (Hayward et al. 2014) covering polar areas and mid-latitude will be demonstrated

Estimating reaction rate constants: comparison between traditional curve fitting and curve resolution

NARCIS (Netherlands)

Bijlsma, S.; Boelens, H. F. M.; Hoefsloot, H. C. J.; Smilde, A. K.

2000-01-01

A traditional curve fitting (TCF) algorithm is compared with a classical curve resolution (CCR) approach for estimating reaction rate constants from spectral data obtained in time of a chemical reaction. In the TCF algorithm, reaction rate constants an estimated from the absorbance versus time data

Droplet deposition measurement with high-speed camera and novel high-speed liquid film sensor with high spatial resolution

International Nuclear Information System (INIS)

Damsohn, M.; Prasser, H.-M.

2011-01-01

Highlights: → Development of a sensor for time- and space-resolved droplet deposition in annular flow. → Experimental measurement of droplet deposition in horizontal annular flow to compare readings of the sensor with images of a high-speed camera when droplets are depositing unto the liquid film. → Self-adaptive signal filter based on autoregression to separate droplet impacts in the sensor signal from waves of liquid films. - Abstract: A sensor based on the electrical conductance method is presented for the measurement of dynamic liquid films in two-phase flow. The so called liquid film sensor consists of a matrix with 64 x 16 measuring points, a spatial resolution of 3.12 mm and a time resolution of 10 kHz. Experiments in a horizontal co-current air-water film flow were conducted to test the capability of the sensor to detect droplet deposition from the gas core onto the liquid film. The experimental setup is equipped with the liquid film sensor and a high speed camera (HSC) recording the droplet deposition with a sampling rate of 10 kHz simultaneously. In some experiments the recognition of droplet deposition on the sensor is enhanced by marking the droplets with higher electrical conductivity. The comparison between the HSC and the sensor shows, that the sensor captures the droplet deposition above a certain droplet diameter. The impacts of droplet deposition can be filtered from the wavy structures respectively conductivity changes of the liquid film using a filter algorithm based on autoregression. The results will be used to locally measure droplet deposition e.g. in the proximity of spacers in a subchannel geometry.

Global carbon monoxide vertical distributions from spaceborne high-resolution FTIR nadir measurements

Directory of Open Access Journals (Sweden)

B. Barret

2005-01-01

Full Text Available This paper presents the first global distributions of CO vertical profiles retrieved from a thermal infrared FTS working in the nadir geometry. It is based on the exploitation of the high resolution and high quality spectra measured by the Interferometric Monitor of Greenhouse gases (IMG which flew onboard the Japanese ADEOS platform in 1996-1997. The retrievals are performed with an algorithm based on the Optimal Estimation Method (OEM and are characterized in terms of vertical sensitivity and error budget. It is found that most of the IMG measurements contain between 1.5 and 2.2 independent pieces of information about the vertical distribution of CO from the lower troposphere to the upper troposphere-lower stratosphere (UTLS. The retrievals are validated against coincident NOAA/CMDL in situ surface measurements and NDSC/FTIR total columns measurements. The retrieved global distributions of CO are also found to be in good agreement with the distributions modeled by the GEOS-CHEM 3D CTM, highlighting the ability of IMG to capture the horizontal as well as the vertical structure of the CO distributions.

High resolution hypernuclear spectroscopy at Jefferson Lab Hall A

International Nuclear Information System (INIS)

Garibaldi, F.; Bydžovský, P.; Cisbani, E.; Cusanno, F.; De Leo, R.; Frullani, S.; Iodice, M.; LeRose, J.J.; Markowitz, P.; Millener, D.J.; Urciuoli, G.M.

2013-01-01

The characteristics of the Jefferson Lab electron beam, together with those of the experimental equipment, offer a unique opportunity to study hypernuclear spectroscopy via electromagnetic induced (e,e ′ K + ) reactions. Experiment 94-107 started a systematic study on 1p-shell targets, 12 C, 9 Be and 16 O. For 12 C for the first time measurable strength in the core-excited part of the spectrum between the ground state and the p state was shown in the 12 Λ B spectrum. For 16 O a high-quality 16 Λ N spectrum was produced for the first time with sub-MeV energy resolution. A very precise Λ binding energy value for 16 Λ N, calibrated against the elementary (e,e ′ K + ) reaction on hydrogen, has also been obtained. Preliminary data on the 9 Λ Li spectrum shows some disagreement in strength for the second and third doublet with respect to the theory

High-resolution noise substitution to measure overfitting and validate resolution in 3D structure determination by single particle electron cryomicroscopy.

Science.gov (United States)

Chen, Shaoxia; McMullan, Greg; Faruqi, Abdul R; Murshudov, Garib N; Short, Judith M; Scheres, Sjors H W; Henderson, Richard

2013-12-01

Three-dimensional (3D) structure determination by single particle electron cryomicroscopy (cryoEM) involves the calculation of an initial 3D model, followed by extensive iterative improvement of the orientation determination of the individual particle images and the resulting 3D map. Because there is much more noise than signal at high resolution in the images, this creates the possibility of noise reinforcement in the 3D map, which can give a false impression of the resolution attained. The balance between signal and noise in the final map at its limiting resolution depends on the image processing procedure and is not easily predicted. There is a growing awareness in the cryoEM community of how to avoid such over-fitting and over-estimation of resolution. Equally, there has been a reluctance to use the two principal methods of avoidance because they give lower resolution estimates, which some people believe are too pessimistic. Here we describe a simple test that is compatible with any image processing protocol. The test allows measurement of the amount of signal and the amount of noise from overfitting that is present in the final 3D map. We have applied the method to two different sets of cryoEM images of the enzyme beta-galactosidase using several image processing packages. Our procedure involves substituting the Fourier components of the initial particle image stack beyond a chosen resolution by either the Fourier components from an adjacent area of background, or by simple randomisation of the phases of the particle structure factors. This substituted noise thus has the same spectral power distribution as the original data. Comparison of the Fourier Shell Correlation (FSC) plots from the 3D map obtained using the experimental data with that from the same data with high-resolution noise (HR-noise) substituted allows an unambiguous measurement of the amount of overfitting and an accompanying resolution assessment. A simple formula can be used to calculate an

Energetics of small scale turbulence in the lower stratosphere from high resolution radar measurements

Directory of Open Access Journals (Sweden)

J. Dole

Full Text Available Very high resolution radar measurements were performed in the troposphere and lower stratosphere by means of the PROUST radar. The PROUST radar operates in the UHF band (961 MHz and is located in St. Santin, France (44°39’ N, 2°12’ E. A field campaign involving high resolution balloon measurements and the PROUST radar was conducted during April 1998. Under the classical hypothesis that refractive index inhomogeneities at half radar wavelength lie within the inertial subrange, assumed to be isotropic, kinetic energy and temperature variance dissipation rates were estimated independently in the lower stratosphere. The dissipation rate of temperature variance is proportional to the dissipation rate of available potential energy. We therefore estimate the ratio of dissipation rates of potential to kinetic energy. This ratio is a key parameter of atmospheric turbulence which, in locally homogeneous and stationary conditions, is simply related to the flux Richardson number, R_f .

Key words. Meteorology and atmospheric dynamics (turbulence – Radio science (remote sensing

MARVEL analysis of the measured high-resolution spectra of 14NH3

International Nuclear Information System (INIS)

Al Derzi, Afaf R.; Furtenbacher, Tibor; Tennyson, Jonathan; Yurchenko, Sergei N.; Császár, Attila G.

2015-01-01

Accurate, experimental rotational–vibrational energy levels and line positions, with associated labels and uncertainties, are reported for the ground electronic state of the symmetric-top 14 NH 3 molecule. All levels and lines are based on critically reviewed and validated high-resolution experimental spectra taken from 56 literature sources. The transition data are in the 0.7–17 000 cm −1 region, with a large gap between 7000 and 15 000 cm −1 . The MARVEL (Measured Active Rotational–Vibrational Energy Levels) algorithm is used to determine the energy levels. Out of the 29 450 measured transitions 10 041 and 18 947 belong to ortho- and para- 14 NH 3 , respectively. A careful analysis of the related experimental spectroscopic network (SN) allows 28 530 of the measured transitions to be validated, 18 178 of these are unique, while 462 transitions belong to floating components. Despite the large number of spectroscopic measurements published over the last 80 years, the transitions determine only 30 vibrational band origins of 14 NH 3 , 8 for ortho- and 22 for para- 14 NH 3 . The highest J value, where J stands for the rotational quantum number, for which an energy level is validated is 31. The number of experimental-quality ortho- and para- 14 NH 3 rovibrational energy levels is 1724 and 3237, respectively. The MARVEL energy levels are checked against ones in the BYTe first-principles database, determined previously. The lists of validated lines and levels for 14 NH 3 are deposited in the Supporting Information to this paper. Combination of the MARVEL energy levels with first-principles absorption intensities yields a huge number of experimental-quality rovibrational lines, which should prove to be useful for the understanding of future complex high-resolution spectroscopy on 14 NH 3 ; these lines are also deposited in the Supporting Information to this paper

MARVEL analysis of the measured high-resolution spectra of 14NH3

Science.gov (United States)

Al Derzi, Afaf R.; Furtenbacher, Tibor; Tennyson, Jonathan; Yurchenko, Sergei N.; Császár, Attila G.

2015-08-01

Accurate, experimental rotational-vibrational energy levels and line positions, with associated labels and uncertainties, are reported for the ground electronic state of the symmetric-top 14NH3 molecule. All levels and lines are based on critically reviewed and validated high-resolution experimental spectra taken from 56 literature sources. The transition data are in the 0.7-17 000 cm-1 region, with a large gap between 7000 and 15 000 cm-1. The MARVEL (Measured Active Rotational-Vibrational Energy Levels) algorithm is used to determine the energy levels. Out of the 29 450 measured transitions 10 041 and 18 947 belong to ortho- and para-14NH3, respectively. A careful analysis of the related experimental spectroscopic network (SN) allows 28 530 of the measured transitions to be validated, 18 178 of these are unique, while 462 transitions belong to floating components. Despite the large number of spectroscopic measurements published over the last 80 years, the transitions determine only 30 vibrational band origins of 14NH3, 8 for ortho- and 22 for para-14NH3. The highest J value, where J stands for the rotational quantum number, for which an energy level is validated is 31. The number of experimental-quality ortho- and para-14NH3 rovibrational energy levels is 1724 and 3237, respectively. The MARVEL energy levels are checked against ones in the BYTe first-principles database, determined previously. The lists of validated lines and levels for 14NH3 are deposited in the Supporting Information to this paper. Combination of the MARVEL energy levels with first-principles absorption intensities yields a huge number of experimental-quality rovibrational lines, which should prove to be useful for the understanding of future complex high-resolution spectroscopy on 14NH3; these lines are also deposited in the Supporting Information to this paper.

High resolution resistivity measurements at the Down Ampney research site

International Nuclear Information System (INIS)

Hallam, J.R.; Jackson, P.D.; Rainsbury, M.; Raines, M.

1991-01-01

A new high resolution resistivity surveying method is described for fault detection and characterisation. The resolution is shown to be significantly higher than conventional apparent resistivity profiling when applied to geological discontinuities such as faults. Nominal fault locations have been determined to an accuracy of 0.5 m, as proven by drilling. Two dimensional profiling and image enhancement of the resulting 2-D data set indicated the possibility of subsidiary fractures and/or lateral changes within the clay to clay' fault zone. The increased resolution allows greater confidence to be placed on both the fault detection and lateral perturbations derived from processed resistance and resistivity images. (Author)

High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100-300 Å spectral banda)

Science.gov (United States)

Widmann, K.; Beiersdorfer, P.; Magee, E. W.; Boyle, D. P.; Kaita, R.; Majeski, R.

2014-11-01

We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li+ or Li2 +, which radiate near 199 Å and 135 Å, respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 mÅ at the 200 Å setting and better than 40 mÅ for the 135-Å range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Å Li+ and 65 eV for the 135 Å Li2 + lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

First measurements with new high-resolution gadolinium-GEM neutron detectors

CERN Document Server

Pfeiffer, Dorothea; Birch, Jens; Etxegarai, Maddi; Hall-Wilton, Richard; Höglund, Carina; Hultman, Lars; Llamas-Jansa, Isabel; Oliveri, Eraldo; Oksanen, Esko; Robinson, Linda; Ropelewski, Leszek; Schmidt, Susann; Streli, Christina; Thuiner, Patrik

2016-05-17

European Spallation Source instruments like the macromolecular diffractometer, NMX, require an excellent neutron detection efficiency, high-rate capabilities, time resolution, and an unprecedented spatial resolution in the order of a few hundred micrometers over a wide angular range of the incoming neutrons. For these instruments solid converters in combination with Micro Pattern Gaseous Detectors (MPGDs) are a promising option. A GEM detector with gadolinium converter was tested on a cold neutron beam at the IFE research reactor in Norway. The {\\mu}TPC analysis, proven to improve the spatial resolution in the case of $^{10}$B converters, is extended to gadolinium based detectors. For the first time, a Gd-GEM was successfully operated to detect neutrons with an estimated efficiency of 10% at a wavelength of 2 {\\AA} and a position resolution better than 350 {\\mu}m.

Isotope specific resolution recovery image reconstruction in high resolution PET imaging

Energy Technology Data Exchange (ETDEWEB)

Kotasidis, Fotis A. [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva, Switzerland and Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, M20 3LJ, Manchester (United Kingdom); Angelis, Georgios I. [Faculty of Health Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2006, Sydney (Australia); Anton-Rodriguez, Jose; Matthews, Julian C. [Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester M20 3LJ (United Kingdom); Reader, Andrew J. [Montreal Neurological Institute, McGill University, Montreal QC H3A 2B4, Canada and Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King' s College London, St. Thomas’ Hospital, London SE1 7EH (United Kingdom); Zaidi, Habib [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Geneva Neuroscience Centre, Geneva University, CH-1205 Geneva (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, PO Box 30 001, Groningen 9700 RB (Netherlands)

2014-05-15

Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution

Isotope specific resolution recovery image reconstruction in high resolution PET imaging

International Nuclear Information System (INIS)

Kotasidis, Fotis A.; Angelis, Georgios I.; Anton-Rodriguez, Jose; Matthews, Julian C.; Reader, Andrew J.; Zaidi, Habib

2014-01-01

Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution

Isotope specific resolution recovery image reconstruction in high resolution PET imaging.

Science.gov (United States)

Kotasidis, Fotis A; Angelis, Georgios I; Anton-Rodriguez, Jose; Matthews, Julian C; Reader, Andrew J; Zaidi, Habib

2014-05-01

Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution recovery image reconstruction. The

High-resolution multi-slice PET

International Nuclear Information System (INIS)

Yasillo, N.J.; Chintu Chen; Ordonez, C.E.; Kapp, O.H.; Sosnowski, J.; Beck, R.N.

1992-01-01

This report evaluates the progress to test the feasibility and to initiate the design of a high resolution multi-slice PET system. The following specific areas were evaluated: detector development and testing; electronics configuration and design; mechanical design; and system simulation. The design and construction of a multiple-slice, high-resolution positron tomograph will provide substantial improvements in the accuracy and reproducibility of measurements of the distribution of activity concentrations in the brain. The range of functional brain research and our understanding of local brain function will be greatly extended when the development of this instrumentation is completed

High resolution alpha-autoradiography for measurement of 10B distribution in subcellular scale using CR-39 and AFM

International Nuclear Information System (INIS)

Amemiya, K.; Takahashi, H.; Yasuda, N.

2000-01-01

In order to measure 10 B distribution in tumor tissues for BNCT at subcellular scale, we have developed a new method for high resolution alpha-autoradiography using contact X-ray microscopy technique with CR-39 plastic track detectors. Sliced sections of boron-injected brain tumors in rats were mounted on CR-39 and irradiated with thermal neutrons at KUR. Then the samples were exposed to soft X-rays from a laser plasma source. After etching the CR-39 in NaOH solution for a short time (1-5 min.), transmission X-ray image of tumor cells appeared as relief on CR-39 surface, and could be observed with the atomic force microscopy (AFM). Very small etch pits of about 100 nm in diameter corresponding to particle tracks from 10 B(n, α) 7 Li reactions were also observed in the image simultaneously. This method provides an accurate distribution of 10 B inside the cell. (author)

Aspects of kinematical coincidence measurements of excitation energy division in damped reactions

International Nuclear Information System (INIS)

Toke, J.; Schroeder, W.U.; Huizenga, J.R.; Rochester Univ., NY

1990-01-01

It is shown that the finite resolution inherent in the kinematical coincidence method leads to systematic errors in the deduced (primary) physical quantities if the latter are calculated based on mass and linear momentum conservation equations alone. As an example, application of this method for measuring excitation energy of the fragments from damped reactions is reviewed. In such a case, finite resolution effects generate significant instrumental, or 'background' correlations between the physical quantities reconstructed in a straightforward fashion, hence, if not accounted for, they may lead to the qualitative misinterpretation of the data. Experimental measures are discussed which appear necessary in order to ensure proper accuracy of the finite resolution corrections. An alternative method of data analysis is presented which is much less susceptible to the finite resolution effects discussed. (orig.)

Comparison of high-resolution Scheimpflug and high-frequency ultrasound biomicroscopy to anterior-segment OCT corneal thickness measurements

Directory of Open Access Journals (Sweden)

Kanellopoulos AJ

2013-11-01

Full Text Available Anastasios John Kanellopoulos,1,2 George Asimellis1 1Laservision.gr Eye Institute, Athens, Greece; 2New York University Medical School, New York, NY, USA Background: The purpose of this study was to compare and correlate central corneal thickness in healthy, nonoperated eyes with three advanced anterior-segment imaging systems: a high-resolution Scheimpflug tomography camera (Oculyzer II, a spectral-domain anterior-segment optical coherence tomography (AS-OCT system, and a high-frequency ultrasound biomicroscopy (HF-UBM system. Methods: Fifty eyes randomly selected from 50 patients were included in the study. Inclusion criteria were healthy, nonoperated eyes examined consecutively by the same examiner. Corneal imaging was performed by three different methods, ie, Oculyzer II, spectral-domain AS-OCT, and FH-UBM. Central corneal thickness measurements were compared using scatter diagrams, Bland-Altman plots (with bias and 95% confidence intervals, and two-paired analysis. Results: The coefficient of determination (r2 between the Oculyzer II and AS-OCT measurements was 0.895. Likewise, the coefficient was 0.893 between the Oculyzer II and HF-UBM and 0.830 between the AS-OCT and HF-UBM. The trend line coefficients of linearity were 0.925 between the Oculyzer II and the AS-OCT, 1.006 between the Oculyzer II and HF-UBM, and 0.841 between the AS-OCT and HF-UBM. The differences in average corneal thickness between the three pairs of CCT measurements were –6.86 µm between the Oculyzer II and HF-UBM, –12.20 µm between the AS-OCT and Oculyzer II, and +19.06 µm between the HF-UBM and AS-OCT. Conclusion: The three methods used for corneal thickness measurement are highly correlated. Compared with the Scheimplug and ultrasound devices, the AS-OCT appears to report a more accurate, but overally thinner corneal pachymetry. Keywords: anterior eye segment, high-frequency ultrasound biomicroscopy, optical coherence tomography, high-resolution Pentacam

High resolution time-of-flight measurements in small and large scintillation counters

International Nuclear Information System (INIS)

D'Agostini, G.; Marini, G.; Martellotti, G.; Massa, F.; Rambaldi, A.; Sciubba, A.

1981-01-01

In a test run, the experimental time-of-flight resolution was measured for several different scintillation counters of small (10 x 5 cm 2 ) and large (100 x 15 cm 2 and 75 x 25 cm 2 ) area. The design characteristics were decided on the basis of theoretical Monte Carlo calculations. We report results using twisted, fish-tail, and rectangular light- guides and different types of scintillator (NE 114 and PILOT U). Time resolution up to approx. equal to 130-150 ps fwhm for the small counters and up to approx. equal to 280-300 ps fwhm for the large counters were obtained. The spatial resolution from time measurements in the large counters is also reported. The results of Monte Carlo calculations on the type of scintillator, the shape and dimensions of the light-guides, and the nature of the external wrapping surfaces - to be used in order to optimize the time resolution - are also summarized. (orig.)

High-Resolution UV Relay Lens for Particle Size Distribution Measurements Using Holography

Energy Technology Data Exchange (ETDEWEB)

Malone, Robert M.; Capelle, Gene A.; Frogget, Brent C.; Grover, Mike; Kaufman, Morris I.; Pazuchanics, Peter; Sorenson, Danny S.; Stevens, Gerald D.; Tibbits, Aric; Turley, William D.

2008-08-29

Shock waves passing through a metal sample can produce ejecta particulates at a metal-vacuum interface. Holography records particle size distributions by using a high-power, short-pulse laser to freeze particle motion. The sizes of the ejecta particles are recorded using an in-line Fraunhofer holography technique. Because the holographic plate would be destroyed in an energetic environment, a high-resolution lens has been designed to relay the interference fringes to a safe environment. Particle sizes within a 12-mm-diameter, 5-mm-thick volume are recorded onto holographic film. To achieve resolution down to 0.5 μm, ultraviolet laser (UV) light is needed. The design and assembly of a nine-element lens that achieves >2000 lp/mm resolution and operates at f/0.89 will be described. To set up this lens system, a doublet lens is temporarily attached that enables operation with 532-nm laser light and 1100 lp/mm resolution. Thus, the setup and alignment are performed with green light, but the dynamic recording is done with UV light. During setup, the 532-nm beam provides enough focus shift to accommodate the placement of a resolution target outside the ejecta volume; this resolution target does not interfere with the calibrated wires and pegs surrounding the ejecta volume. A television microscope archives images of resolution patterns that prove that the calibration wires, interference filter, holographic plate, and relay lenses are in their correct positions. Part of this lens is under vacuum, at the point where the laser illumination passes through a focus. Alignment and tolerancing of this high-resolution lens will be presented, and resolution variation through the 5-mm depth of field will be discussed.

High resolution optical spectroscopy of air-induced electrical instabilities in n-type polymer semiconductors.

Science.gov (United States)

Di Pietro, Riccardo; Sirringhaus, Henning

2012-07-03

We use high-resolution charge-accumulation optical spectroscopy to measure charge accumulation in the channel of an n-type organic field-effect transistor. We monitor the degradation of device performance in air, correlate the onset voltage shift with the reduction of charge accumulated in the polymer semiconductor, and explain the results in view of the redox reaction between the polymer, water and oxygen in the accumulation layer. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-resolution X-ray diffraction studies of multilayers

DEFF Research Database (Denmark)

Christensen, Finn Erland; Hornstrup, Allan; Schnopper, H. W.

1988-01-01

High-resolution X-ray diffraction studies of the perfection of state-of-the-art multilayers are presented. Data were obtained using a triple-axis perfect-crystal X-ray diffractometer. Measurements reveal large-scale figure errors in the substrate. A high-resolution triple-axis set up is required...

Quantitative measurement of zinc secretion from pancreatic islets with high temporal resolution using droplet-based microfluidics.

Science.gov (United States)

Easley, Christopher J; Rocheleau, Jonathan V; Head, W Steven; Piston, David W

2009-11-01

We assayed glucose-stimulated insulin secretion (GSIS) from live, murine islets of Langerhans in microfluidic devices by the downstream formation of aqueous droplets. Zinc ions, which are cosecreted with insulin from beta-cells, were quantitatively measured from single islets with high temporal resolution using a fluorescent indicator, FluoZin-3. Real-time storage of secretions into droplets (volume of 0.470 +/- 0.009 nL) effectively preserves the temporal chemical information, allowing reconstruction of the secretory time record. The use of passive flow control within the device removes the need for syringe pumps, requiring only a single hand-held syringe. Under stimulatory glucose levels (11 mM), bursts of zinc as high as approximately 800 fg islet(-1) min(-1) were measured. Treatment with diazoxide effectively blocked zinc secretion, as expected. High temporal resolution reveals two major classes of oscillations in secreted zinc, with predominate periods at approximately 20-40 s and approximately 5-10 min. The more rapid oscillation periods match closely with those of intraislet calcium oscillations, while the slower oscillations are consistent with insulin pulses typically measured in bulk islet experiments or in the bloodstream. This droplet sampling technique should be widely applicable to time-resolved cellular secretion measurements, either in real-time or for postprocessing.

High resolution NMR imaging using a high field yokeless permanent magnet.

Science.gov (United States)

Kose, Katsumi; Haishi, Tomoyuki

2011-01-01

We measured the homogeneity and stability of the magnetic field of a high field (about 1.04 tesla) yokeless permanent magnet with 40-mm gap for high resolution nuclear magnetic resonance (NMR) imaging. Homogeneity was evaluated using a 3-dimensional (3D) lattice phantom and 3D spin-echo imaging sequences. In the central sphere (20-mm diameter), peak-to-peak magnetic field inhomogeneity was about 60 ppm, and the root-mean-square was 8 ppm. We measured room temperature, magnet temperature, and NMR frequency of the magnet simultaneously every minute for about 68 hours with and without the thermal insulator of the magnet. A simple mathematical model described the magnet's thermal property. Based on magnet performance, we performed high resolution (up to [20 µm](2)) imaging with internal NMR lock sequences of several biological samples. Our results demonstrated the usefulness of the high field small yokeless permanent magnet for high resolution NMR imaging.

High resolution NMR imaging using a high field yokeless permanent magnet

International Nuclear Information System (INIS)

Kose, Katsumi; Haishi, Tomoyuki

2011-01-01

We measured the homogeneity and stability of the magnetic field of a high field (about 1.04 tesla) yokeless permanent magnet with 40-mm gap for high resolution nuclear magnetic resonance (NMR) imaging. Homogeneity was evaluated using a 3-dimensional (3D) lattice phantom and 3D spin-echo imaging sequences. In the central sphere (20-mm diameter), peak-to-peak magnetic field inhomogeneity was about 60 ppm, and the root-mean-square was 8 ppm. We measured room temperature, magnet temperature, and NMR frequency of the magnet simultaneously every minute for about 68 hours with and without the thermal insulator of the magnet. A simple mathematical model described the magnet's thermal property. Based on magnet performance, we performed high resolution (up to [20 μm] 2 ) imaging with internal NMR lock sequences of several biological samples. Our results demonstrated the usefulness of the high field small yokeless permanent magnet for high resolution NMR imaging. (author)

Application of the high-spin isomer beams to the secondary fusion reaction and the measurement of g-factor

International Nuclear Information System (INIS)

Watanabe, H.; Asahi, K.; Kishida, T.; Ueno, H.; Sato, W.; Yoshimi, A.; Kobayashi, Y.; Kameda, D.; Miyoshi, H.; Fukuchi, T.; Wakabayashi, Y.; Sasaki, T.; Kibe, M.; Hokoiwa, N.; Odahara, A.; Cederwall, B.; Lagergren, K.; Podolyak, Zs.; Ishihara, M.; Gono, Y.

2004-01-01

A technique for providing high-spin isomers as probes of the fusion reaction and the measurement of g-factor has been worked out at RIKEN. In the study of the fusion reaction 12 C( 145m Sm,xn) 157-x Er, the γ rays emitted from the fusion-evaporation residue 154 Er have been successfully observed. The nuclear g-factor of the T 1/2 = 28 ns high-spin isomer in 149 Dy has been measured with the γ-ray TDPAD method

The investigation of Martian dune fields using very high resolution photogrammetric measurements and time series analysis

Science.gov (United States)

Kim, J.; Park, M.; Baik, H. S.; Choi, Y.

2016-12-01

At the present time, arguments continue regarding the migration speeds of Martian dune fields and their correlation with atmospheric circulation. However, precisely measuring the spatial translation of Martian dunes has rarely conducted only a very few times Therefore, we developed a generic procedure to precisely measure the migration of dune fields with recently introduced 25-cm resolution High Resolution Imaging Science Experimen (HIRISE) employing a high-accuracy photogrammetric processor and sub-pixel image correlator. The processor was designed to trace estimated dune migration, albeit slight, over the Martian surface by 1) the introduction of very high resolution ortho images and stereo analysis based on hierarchical geodetic control for better initial point settings; 2) positioning error removal throughout the sensor model refinement with a non-rigorous bundle block adjustment, which makes possible the co-alignment of all images in a time series; and 3) improved sub-pixel co-registration algorithms using optical flow with a refinement stage conducted on a pyramidal grid processor and a blunder classifier. Moreover, volumetric changes of Martian dunes were additionally traced by means of stereo analysis and photoclinometry. The established algorithms have been tested using high-resolution HIRISE images over a large number of Martian dune fields covering whole Mars Global Dune Database. Migrations over well-known crater dune fields appeared to be almost static for the considerable temporal periods and were weakly correlated with wind directions estimated by the Mars Climate Database (Millour et al. 2015). Only over a few Martian dune fields, such as Kaiser crater, meaningful migration speeds (>1m/year) compared to phtotogrammetric error residual have been measured. Currently a technical improved processor to compensate error residual using time series observation is under developing and expected to produce the long term migration speed over Martian dune

High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100–300 Å spectral band

Energy Technology Data Exchange (ETDEWEB)

Widmann, K., E-mail: widmann1@llnl.gov; Beiersdorfer, P.; Magee, E. W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Boyle, D. P.; Kaita, R.; Majeski, R. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2014-11-15

We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li{sup +} or Li{sup 2+}, which radiate near 199 Å and 135 Å, respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 mÅ at the 200 Å setting and better than 40 mÅ for the 135-Å range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Å Li{sup +} and 65 eV for the 135 Å Li{sup 2+} lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

High-resolution absorption measurements of NH₃ at high temperatures: 500–2100cm⁻¹

DEFF Research Database (Denmark)

Barton, Emma J.; Yurchenko, Sergei N.; Tennyson, Jonathan

2015-01-01

High-resolution absorption spectra of NH3 in the region 500–2100 cm -1 at temperatures up to1027 1C and approximately atmospheric pressure (1013±20 mbar) are measured. NH3 concentrations of 1000 ppm,0.5% and 1% in volume fraction were used in the measurements. Spectra are recorded in high tempera...... to a variational line list, BYTe, and experimental energy levels determined using the MARVEL procedure. Approximately 2000 lines have been assigned, of which 851are newly assigned to mainly hot bands involving vibrational states as high as v2=5....

High-resolution measurement and mapping of tungstate in waters, soils and sediments using the low-disturbance DGT sampling technique

Energy Technology Data Exchange (ETDEWEB)

Guan, Dong-Xing [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Williams, Paul N. [Institute for Global Food Security, School of Biological Sciences, Queen’s University Belfast, Belfast BT9 7BL (United Kingdom); Xu, Hua-Cheng [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008 (China); Li, Gang [Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Luo, Jun, E-mail: esluojun@nju.edu.cn [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Ma, Lena Q. [State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023 (China); Soil and Water Science Department, University of Florida, Gainesville, FL 32611 (United States)

2016-10-05

Highlights: • Two high-resolution diffusive gradients in thin-films samplers were characterized. • For the first time DGT was applied to study the bioavailability of W in soils. • 1D and 2D high resolution profiling of W fluxes across the SWI were obtained. • The apparent diffusion W fluxes across two micro-interfaces were calculated. - Abstract: Increasing tungsten (W) use for industrial and military applications has resulted in greater W discharge into natural waters, soils and sediments. Risk modeling of W transport and fate in the environment relies on measurement of the release/mobilization flux of W in the bulk media and the interfaces between matrix compartments. Diffusive gradients in thin-films (DGT) is a promising passive sampling technique to acquire such information. DGT devices equipped with the newly developed high-resolution binding gels (precipitated zirconia, PZ, or ferrihydrite, PF, gels) or classic/conventional ferrihydrite slurry gel were comprehensively assessed for measuring W in waters. {sup Ferrihydrite}DGT can measure W at various ionic strengths (0.001–0.5 mol L{sup −1} NaNO{sub 3}) and pH (4–8), while {sup PZ}DGT can operate across slightly wider environmental conditions. The three DGT configurations gave comparable results for soil W measurement, showing that typically W resupply is relatively poorly sustained. 1D and 2D high-resolution W profiling across sediment—water and hotspot—bulk media interfaces from Lake Taihu were obtained using {sup PZ}DGT coupled with laser ablation ICP–MS measurement, and the apparent diffusion fluxes across the interfaces were calculated using a numerical model.

New high resolution measurements of open and hidden charm production in proton-nucleus collisions at √{ s} = 110GeV with LHCb

Science.gov (United States)

Maurice, Émilie; LHCb Collaboration

2017-11-01

Open and hidden charm production in nucleus-nucleus collisions is considered as a key probe of Quark Gluon Plasma (QGP) formation. In the search of specific QGP effects, proton-nucleus collisions are used as the reference as they account for the corresponding Cold Nuclear Matter (CNM) effects. The LHCb experiment, thanks to its System for Measuring Overlap with Gas (SMOG) can be operated in a fixed target mode with the LHC beams, at an intermediate center-of-mass energy between nominal SPS and RHIC energies. In 2015, for the first time, reactions of incident LHC proton beams on noble gas targets have been recorded by the LHCb experiment at a center-of-mass energy of 110 GeV and within the center-of-mass rapidity range - 2.77 high resolution measurements on open and hidden charm production obtained under these conditions are presented.

Targets for high-resolution studies with heavy-ion reactions

International Nuclear Information System (INIS)

Erskine, J.R.

1975-01-01

Target problems in heavy ion reaction studies are discussed, including non-uniformity in thickness effects and the inability to fully compensate for reaction-site effects, both problems becoming more serious the heavier the ion. For the non-uniformity effects, the flatness of the target is very critical. Other problems not yet solved are beam-spot heating and the buildup of carbon

Measurement and analysis of cross sections for (p,x) reactions on natural molybdenum

International Nuclear Information System (INIS)

Challan, M. B.; Comsan, M.N.H.; Abou-Zeid, M.A.

2006-01-01

Excitation functions (EFs) for the reactions n atMo(p,x) 92m Nb, and n atMo(p,x) 94 , 95m , 95g , 96 m, +g , 99m Tc up to 18 MeV from threshold have been measured employing the stacked foil activation technique, and using high resolution HPGe gamma spectrometry. Utilizing the simultaneous measurement of the excitation function of n atCu(p,x) 62 Zn, n atCu(p,x) 63 Zn, n atCu(p,x) 65 Zn, and n atTi(p,x) 48 V monitor reactions. The theoretical analysis of the EFs has been done using both the semi-classical as well as quantum mechanical codes which include compound nucleus and pre-equilibrium (PE) emission into consideration. In general, theoretical calculations agree well with the experimental data. Effect of various free parameters used in the calculations has also been discussed. A significant contribution of pre-equilibrium component has been observed at these energies

High resolution data acquisition

Science.gov (United States)

Thornton, Glenn W.; Fuller, Kenneth R.

1993-01-01

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

High spatial resolution measurement of depth-of-interaction of a PET LSO crystal

International Nuclear Information System (INIS)

Simon, A.; Kalinka, G.; Novak, D.; Sipos, A.; Vegh, J.; Molnar, J.

2004-01-01

Complete text of publication follows. A new type of experimental technique to investigate the depth-of-interaction (DOI) dependence in small scintillator elements designed for high-resolution animal PET [1] has been introduced at our institute, recently. A lutetium oxyorthosilicate (LSO) crystal (2x2x10 mm 3 ) was irradiated with a highly focused 2 MeV He + beam at the ATOMKI nuclear microprobe laboratory. Pulse height spectra from a photomultiplier (PMT) attached to one end of the LSO crystal were collected in list mode. Sequential scans of 1000x1000 μm 2 areas along the 10 mm long crystal were made to get high lateral resolution images of pulse height spectra at different distances from the window of the PMT. A mean pulse height algorithm was applied to each pixel to generate two dimensional intensity images and the corresponding spectra of 100 μmx1 mm areas. Representative pulse height spectra are shown in Fig. 1 for different distances between the position of irradiation and the PMT. The mean value of the pulse height spectrum describing the position of the full energy peak is a way to measure DOI effects. It is seen that the closer the DOI to the PMT-end of the crystal the higher the energy of the peak. The centre of the detected peak varies about 30 % along the lateral side of the crystal. This effect is due to the increasing number of reflections with associated loss of light when the distance between the DOI position and the light collecting PMT grows. Further these results, no difference in the light intensity was found depending on which position across (perpendicular to the length of) the crystal was irradiated with the microbeam. The obtained results of the overall DOI dependence confirm previous measurements on LSO crystals with similar geometry and wrapping but based on collimated gamma-ray irradiation. Since the present experimental setup allows obtaining data with several orders of magnitude better spatial resolution (from μm up to mm) than with

High resolution measurement of the velocity profiles of channel flows using the particle image velocimetry technique

International Nuclear Information System (INIS)

Nor Azizi Mohamed

2000-01-01

The high resolution velocity profiles of a uniform steady channel flow and a flow beneath waves were obtained using the particle image velocimetry (PIV) technique. The velocity profiles for each flow were calculated for both components. It is shown that the profiles obtained are very precise, displaying the point velocities from a few millimeters from the bottom of the channel up to the water surface across the water depth. In the case of the wave-induced flow, the profiles are shown under the respective wave phases and given in a plane representation. High resolution measurement of point velocities in a flow is achievable using PIV and invaluable when applied to a complex flow. (Author)

High resolution investigation of the 30Si(þ, þ)30Si reaction

NARCIS (Netherlands)

Walinga, J.; Rinsvelt, H.A. van; Endt, P.M.

The differential cross section for elastic scattering of protons on 30Si was measured with surface barrier counters at four angles. Thirty-six 30Si(þ, γ)31P resonances are known in the Ep=1–2MeV region. Fifteen of these were also observed in the 30Si(þ, þ)30Si reaction, with natural widths varying

Accurate 238U(n , 2 n )237U reaction cross-section measurements from 6.5 to 14.8 MeV

Science.gov (United States)

Krishichayan, Bhike, M.; Tornow, W.; Tonchev, A. P.; Kawano, T.

2017-10-01

The cross section for the 238U(n ,2 n )237U reaction has been measured in the incident neutron energy range from 6.5 to 14.8 MeV in small energy steps using an activation technique. Monoenergetic neutron beams were produced via the 2H(d ,n )3He and 3H(d ,n )4He reactions. 238U targets were activated along with Au and Al monitor foils to determine the incident neutron flux. The activity of the reaction products was measured in TUNL's low-background counting facility using high-resolution γ -ray spectroscopy. The results are compared with previous measurements and latest data evaluations. Statistical-model calculations, based on the Hauser-Feshbach formalism, have been carried out using the CoH3 code and are compared with the experimental results. The present self-consistent and high-quality data are important for stockpile stewardship and nuclear forensic purposes as well as for the design and operation of fast reactors.

The implementing of high resolution time measuring circuit based on FPGA

International Nuclear Information System (INIS)

Zhang Ji; Zeng Yun; Wang Zheng; Li Quiju; Lu Jifang; Wu Jinyuan

2011-01-01

It presents the implementing of TDC based on FPGA. The fine timing function part is accomplished through the time interpolators that are composed of the carry chain of intrinsic adders in FPGA. This architecture dates back to the latest technology-WUTDC (Wave Union TDC) that is developed to sub-divide the ultra-wide bins and improve the measure resolution. The board and the online test have been proved that the linearity of converters is satisfying and the time resolution is better than 40 ps. (authors)

Development of High Resolution Resonance Ionization Mass Spectrometry for Neutron Dosimetry Technique with93Nb(n,n'93mNb Reaction

Directory of Open Access Journals (Sweden)

Tomita Hideki

2016-01-01

Full Text Available We have proposed an advanced technique to measure the 93mNb yield precisely by Resonance Ionization Mass Spectrometry, instead of conventional characteristic X-ray spectroscopy. 93mNb-selective resonance ionization is achievable by distinguishing the hyperfine splitting of the atomic energy levels between 93Nb and 93mNb at high resolution. In advance of 93mNb detection, we could successfully demonstrate high resolution resonant ionization spectroscopy of stable 93Nb using an all solid-state, narrow-band and tunable Ti:Sapphire laser system operated at 1 kHz repetition rate.

Fall speed measurement and high-resolution multi-angle photography of hydrometeors in free fall

Directory of Open Access Journals (Sweden)

T. J. Garrett

2012-11-01

Full Text Available We describe here a new instrument for imaging hydrometeors in free fall. The Multi-Angle Snowflake Camera (MASC captures high-resolution photographs of hydrometeors from three angles while simultaneously measuring their fall speed. Based on the stereoscopic photographs captured over the two months of continuous measurements obtained at a high altitude location within the Wasatch Front in Utah, we derive statistics for fall speed, hydrometeor size, shape, orientation and aspect ratio. From a selection of the photographed hydrometeors, an illustration is provided for how the instrument might be used for making improved microwave scattering calculations. Complex, aggregated snowflake shapes appear to be more strongly forward scattering, at the expense of reduced back-scatter, than heavily rimed graupel particles of similar size.

Measurement of 167Er(n,p)167Ho reaction at 13.5 and 14.8 MeV

International Nuclear Information System (INIS)

Luo, Junhua; Liu, Jun; Han, Jiuning; Jiang, Li; Liu, Rong; Ge, Suhong; Liu, Zhenlai

2013-01-01

We have measured the 167 Er(n,p) 167 Ho cross-sections at two different neutron energies 13.5 and 14.8 MeV. Measurements were performed at Pd-300 neutron generator of Chinese Academy of Engineering Physics (CAEP) with monoenergetic neutrons produced via the 3 H(d,n) 4 He reaction using a tritium–titanium (T–Ti) target. Induced gamma activities were measured by a high-resolution gamma-ray spectrometer with high-purity germanium (HPGe) detector. The data for 167 Er(n,p) 167 Ho reaction cross-sections are reported to be 2.2±0.6 and 2.8±1.4 mb at 13.5±0.2 and 14.8±0.2 MeV incident neutron energies, respectively. The cross sections were also estimated with the TALYS-1.4 nuclear model code and compared with experimental data found in the literature, and with the comprehensive evaluation data in ENDF/B-VII.1 and JEFF-3.1/A libraries. - Highlights: • D–T neutron source was used to measure cross sections using activation method. • 27 Al(n,α) 24 Na was used as the monitor for the measurement. • The cross sections for the 167 Er(n,p) 167 Ho reactions have been measured. • Contribution of the interfering reaction 170 Er(n,α) 167 Dy was subtracted. • The results were compared with previous data and with evaluation data

Achieving sensitive, high-resolution laser spectroscopy at CRIS

Energy Technology Data Exchange (ETDEWEB)

Groote, R. P. de [Instituut voor Kern- en Stralingsfysica, KU Leuven (Belgium); Lynch, K. M., E-mail: kara.marie.lynch@cern.ch [EP Department, CERN, ISOLDE (Switzerland); Wilkins, S. G. [The University of Manchester, School of Physics and Astronomy (United Kingdom); Collaboration: the CRIS collaboration

2017-11-15

The Collinear Resonance Ionization Spectroscopy (CRIS) experiment, located at the ISOLDE facility, has recently performed high-resolution laser spectroscopy, with linewidths down to 20 MHz. In this article, we present the modifications to the beam line and the newly-installed laser systems that have made sensitive, high-resolution measurements possible. Highlights of recent experimental campaigns are presented.

Conceptual design of high resolution and reliable density measurement system on helical reactor FFHR-d1 and demonstration on LHD

International Nuclear Information System (INIS)

Akiyama, T.; Yasuhara, R.; Isobe, M.; Sakamoto, R.; Goto, T.; Kawahata, K.; Sagara, A.; Nakayama, K.; Okajima, S.

2014-10-01

This paper describes a conceptual design of the density measurement system on the helical reactor FFHR-d1 based on its quantitative operation scenario. The density measurement is required to meet the reactor design, and to have a high density resolution of the order of 10 17 m -3 with a time resolution of 10 ms and high reliability (no fringe jump). “A dispersion interferometer” is designed and a prototype is tested and installed on LHD, which can realize a demo relevant density plasma. The prototype demonstrates the feasibility on a demo reactor. (author)

Parents' reactions to the diagnosis of cerebral palsy: associations between resolution, age and severity of disability

NARCIS (Netherlands)

Schuengel, C.; Rentinck, I.C.M.; Stolk, J.; Voorman, J.M.; Loots, G.M.P.; Ketelaar, M.; Gorter, J.W.; Becher, J.G.

2009-01-01

Background: For parents, receiving a diagnosis, typically in early childhood, that their child has cerebral palsy may conjure up high distress and anxiety. Resolution of these initial reactions may help parents to focus on the challenges and needs of their children. Aims of the study were to test

Parents' reactions to the diagnosis of cerebral palsy: associations between resolution, age and severity of disability

NARCIS (Netherlands)

Schuengel, C.; Rentinck, I.C.M.; Stolk, J.; Voorman, J.M.; Loots, G.M.P.; Ketelaar, M.; Gorter, J.W.; Becher, J.G.

2009-01-01

BACKGROUND: For parents, receiving a diagnosis, typically in early childhood, that their child has cerebral palsy may conjure up high distress and anxiety. Resolution of these initial reactions may help parents to focus on the challenges and needs of their children. AIMS: of the study were to test

Parents' reactions to the diagnosis of cerebral palsy : associations between resolution, age and severity of disability

NARCIS (Netherlands)

Schuengel, C.; Rentinck, I. C. M.; Stolk, J.; Voorman, J. M.; Loots, G. M. P.; Ketelaar, M.; Gorter, J. W.; Becher, J. G.

Background For parents, receiving a diagnosis, typically in early childhood, that their child has cerebral palsy may conjure up high distress and anxiety. Resolution of these initial reactions may help parents to focus on the challenges and needs of their children. Aims of the study were to test

Digital pulse processing techniques for high resolution amplitude measurement of radiation detector

International Nuclear Information System (INIS)

Singhai, P.; Roy, A.; Dhara, P.; Chatterjee, S.

2012-01-01

The digital pulse processing techniques for high resolution amplitude measurement of radiation detector pulse is an effective replacement of expensive and bulky analog processing as the digital domain offers higher channel density and at the same time it is cheaper. We have demonstrated a prototype digital setup with highspeed sampling ADC with sampling frequency of 80-125 MHz followed by series of IIR filters for pulse shaping in a trigger-less acquisition mode. The IIR filters, peak detection algorithm and the data write-out logic was written on VHDL and implemented on FPGA. We used CAMAC as the read out platform. In conjunction with the full hardware implementation we also used a mixed platform with VME digitizer card with raw-sample read out using C code. The rationale behind this mixed platform is to test out various filter algorithms quickly on C and also to benchmark the performance of the chip level ADCs against the standard commercial digitizer in terms of noise or resolution. The paper describes implementation of both the methods with performance obtained in both the methods. (author)

A chronometric exploration of high-resolution 'sensitive TMS masking' effects on subjective and objective measures of vision.

Science.gov (United States)

de Graaf, Tom A; Herring, Jim; Sack, Alexander T

2011-03-01

Transcranial magnetic stimulation (TMS) can induce masking by interfering with ongoing neural activity in early visual cortex. Previous work has explored the chronometry of occipital involvement in vision by using single pulses of TMS with high temporal resolution. However, conventionally TMS intensities have been high and the only measure used to evaluate masking was objective in nature. Recent studies have begun to incorporate subjective measures of vision, alongside objective ones. The current study goes beyond previous work in two regards. First, we explored both objective vision (an orientation discrimination task) and subjective vision (a stimulus visibility rating on a four-point scale), across a wide range of time windows with high temporal resolution. Second, we used a very sensitive TMS-masking paradigm: stimulation was at relatively low TMS intensities, with a figure-8 coil, and the small stimulus was difficult to discriminate already at baseline level. We hypothesized that this should increase the effective temporal resolution of our paradigm. Perhaps for this reason, we are able to report a rather interesting masking curve. Within the classical-masking time window, previously reported to encompass broad SOAs anywhere between 60 and 120 ms, we report not one, but at least two dips in objective performance, with no masking in-between. The subjective measure of vision did not mirror this pattern. These preliminary data from our exploratory design suggest that, with sensitive TMS masking, we might be able to reveal visual processes in early visual cortex previously unreported.

High resolution measurement of light in terrestrial ecosystems using photodegrading dyes.

Directory of Open Access Journals (Sweden)

Javier Roales

Full Text Available Incoming solar radiation is the main determinant of terrestrial ecosystem processes, such as primary production, litter decomposition, or soil mineralization rates. Light in terrestrial ecosystems is spatially and temporally heterogeneous due to the interaction among sunlight angle, cloud cover and tree-canopy structure. To integrate this variability and to know light distribution over time and space, a high number of measurements are needed, but tools to do this are usually expensive and limited. An easy-to-use and inexpensive method that can be used to measure light over time and space is needed. We used two photodegrading fluorescent organic dyes, rhodamine WT (RWT and fluorescein, for the quantification of light. We measured dye photodegradation as the decrease in fluorescence across an irradiance gradient from full sunlight to deep shade. Then, we correlated it to accumulated light measured with PAR quantum sensors and obtained a model for this behavior. Rhodamine WT and fluorescein photodegradation followed an exponential decay curve with respect to accumulated light. Rhodamine WT degraded slower than fluorescein and remained unaltered after exposure to temperature changes. Under controlled conditions, fluorescence of both dyes decreased when temperatures increased, but returned to its initial values after cooling to the pre-heating temperature, indicating no degradation. RWT and fluorescein can be used to measure light under a varying range of light conditions in terrestrial ecosystems. This method is particularly useful to integrate solar radiation over time and to measure light simultaneously at different locations, and might be a better alternative to the expensive and time consuming traditional light measurement methods. The accuracy, low price and ease of this method make it a powerful tool for intensive sampling of large areas and for developing high resolution maps of light in an ecosystem.

Coating Thickness Measurement of the Simulated TRISO-Coated Fuel Particles using an Image Plate and a High Resolution Scanner

International Nuclear Information System (INIS)

Kim, Woong Ki; Kim, Yeon Ku; Jeong, Kyung Chai; Lee, Young Woo; Kim, Bong Goo; Eom, Sung Ho; Kim, Young Min; Yeo, Sung Hwan; Cho, Moon Sung

2014-01-01

In this study, the thickness of the coating layers of 196 coated particles was measured using an Image Plate detector, high resolution scanner and digital image processing techniques. The experimental results are as follows. - An X-ray image was acquired for 196 simulated TRISO-coated fuel particles with ZrO 2 kernel using an Image Plate with high resolution in a reduced amount of time. - We could observe clear boundaries between coating layers for 196 particles. - The geometric distortion error was compensated for the calculation. - The coating thickness of the TRISO-coated fuel particles can be nondestructively measured using X-ray radiography and digital image processing technology. - We can increase the number of TRISO-coated particles to be inspected by increasing the number of Image Plate detectors. A TRISO-coated fuel particle for an HTGR (high temperature gas-cooled reactor) is composed of a nuclear fuel kernel and outer coating layers. The coating layers consist of buffer PyC (pyrolytic carbon), inner PyC (I-PyC), SiC, and outer PyC (O-PyC) layer. The coating thickness is measured to evaluate the soundness of the coating layers. X-ray radiography is one of the nondestructive alternatives for measuring the coating thickness without generating a radioactive waste. Several billion particles are subject to be loaded in a reactor. A lot of sample particles should be tested as much as possible. The acquired X-ray images for the measurement of coating thickness have included a small number of particles because of the restricted resolution and size of the X-ray detector. We tried to test many particles for an X-ray exposure to reduce the measurement time. In this experiment, an X-ray image was acquired for 196 simulated TRISO-coated fuel particles using an image plate and high resolution scanner with a pixel size of 25Χ25 μm 2 . The coating thickness for the particles could be measured on the image

High-resolution X-ray television and high-resolution video recorders

International Nuclear Information System (INIS)

Haendle, J.; Horbaschek, H.; Alexandrescu, M.

1977-01-01

The improved transmission properties of the high-resolution X-ray television chain described here make it possible to transmit more information per television image. The resolution in the fluoroscopic image, which is visually determined, depends on the dose rate and the inertia of the television pick-up tube. This connection is discussed. In the last few years, video recorders have been increasingly used in X-ray diagnostics. The video recorder is a further quality-limiting element in X-ray television. The development of function patterns of high-resolution magnetic video recorders shows that this quality drop may be largely overcome. The influence of electrical band width and number of lines on the resolution in the X-ray television image stored is explained in more detail. (orig.) [de

High resolution spectroscopy in the microwave and far infrared

Science.gov (United States)

Pickett, Herbert M.

1990-01-01

High resolution rotational spectroscopy has long been central to remote sensing techniques in atmospheric sciences and astronomy. As such, laboratory measurements must supply the required data to make direct interpretation of data for instruments which sense atmospheres using rotational spectra. Spectral measurements in the microwave and far infrared regions are also very powerful tools when combined with infrared measurements for characterizing the rotational structure of vibrational spectra. In the past decade new techniques were developed which have pushed high resolution spectroscopy into the wavelength region between 25 micrometers and 2 mm. Techniques to be described include: (1) harmonic generation of microwave sources, (2) infrared laser difference frequency generation, (3) laser sideband generation, and (4) ultrahigh resolution interferometers.

Estimation of residual stress in cold rolled iron-disks from strain measurements on the high resolution Fourier diffractometer

International Nuclear Information System (INIS)

Aksenov, V.L.; Balagurov, A.M.; Taran, Yu.V.

1995-01-01

The results of estimating residual stresses in cold rolled iron disks by measurements with the high resolution Fourier diffractometer (HRFD) at the IBR-2 pulsed reactor are presented. These measurements were made for calibration of magnetic and ultrasonic measurements carried out at the Fraunhofer-Institute for Nondestructive Testing in Saarbrucken (Germany). The tested objects were cold rolled steel disks of 2.5 mm thickness and diameter of about 500 mm used for forming small, gas pressure tanks. Neutron diffraction experiments were carried out at the scattering angle 2θ=+152 d eg with resolution Δd/d=1.5·10 -3 . The gauge volume was chosen according to the magnetic measurements lateral resolution 20x20 mm 2 . In the nearest future the neutron diffraction measurements with cold rolled iron disks at the scattering angle 2θ=±90 0 are planned. Also the texture analysis will be included in the Rietveld refinement procedure for more correct calculation of residual stress fields in the cold rolled materials. 8 refs., 10 figs., 1 tab

High resolution measurements of Cyg X-1 from rockets

International Nuclear Information System (INIS)

Rothschild, R.E.; Boldt, E.A.; Holt, S.S.; Serlemitsos, P.J.

1976-01-01

Cyg X-1 was observed on two occasions (Oct. 4, 1973 and Oct. 3, 1974) by the Goddard x-ray rocket payload. This payload consisted of two gas proportional counters (xenon--methane with 710 cm 2 and argon--methane with 610 cm 2 ) using the same 128 channel pulse height analyzer and having 320 μs temporal resolution on the 1973 flight and 160 μs resolution on the 1974 flight. During both flights bursts of 1 ms duration were observed with very high statistical certainty. To date all 13 of these bursts have been analyzed for spectral and temporal character, and the results of this analysis are presented. The spectra of overall x-ray emission from both flights are also presented. In a source known for its variability it is remarkable that the spectra taken one year apart are virtually identical

a Study of Vibrational Mode Coupling in 2-FLUOROETHANOL and 1,2-DIFLUOROETHANE Using High-Resolution Infrared Spectroscopy.

Science.gov (United States)

Mork, Steven Wayne

High resolution infrared spectroscopy was used to examine intramolecular vibrational interactions in 2 -fluoroethanol (2FE) and 1,2-difluoroethane (DFE). A high resolution infrared spectrophotometer capable of better than 10 MHz spectral resolution was designed and constructed. The excitation source consists of three lasers: an argon-ion pumped dye laser which pumps a color -center laser. The infrared beam from the color-center laser is used to excite sample molecules which are rotationally and vibrationally cooled in a supersonic molecular beam. Rovibrational excitation of the sample molecules is detected by monitoring the kinetic energy of the molecular beam with a bolometer. The high resolution infrared spectrum of 2FE was collected and analyzed over the 2977-2990 cm^ {-1}^ectral region. This region contains the asymmetric CH stretch on the fluorinated carbon. The spectrum revealed extensive perturbations in the rotational fine structure. Analysis of these perturbations has provided a quantitative measure of selective vibrational mode coupling between the C-H stretch and its many neighboring dark vibrational modes. Interestingly, excitation of the C-H stretch is known to induce a photoisomerization reaction between 2FE's Gg^' and Tt conformers. Implications of the role of mode coupling in the reaction mechanism are also addressed. Similarly, the high resolution infrared spectrum of DFE was collected and analyzed over the 2978-2996 cm ^{-1}^ectral region. This region contains the symmetric combination of asymmetric C-H stretches in DFE. Perturbations in the rotational fine structure indicate vibrational mode coupling to a single dark vibrational state. The dark state is split by approximately 19 cm^{-1} due to tunneling between two identical gauche conformers. The coupling mechanism is largely anharmonic with a minor component of B/C-plane Coriolis coupling. Effects of centrifugal distortion along the molecular A-axis are also observed. The coupled vibrational

Design and development of high-resolution atomic beam fluorescence spectroscopy facility for isotope shift and hyperfine structure measurements

International Nuclear Information System (INIS)

Acharyulu, G.V.S.G.; Sankari, M.; Kiran Kumar, P.V.; Suryanarayana, M.V.

2012-01-01

A high-resolution atomic beam fluorescence spectroscopy facility for the determination of isotope shifts and hyperfine structure in atomic species has been designed and developed. A resistively heated graphite tube atomic beam source was designed, tested and integrated into a compact interaction chamber for atomic beam fluorescence experiments. The design of the laser-atom interaction chamber and the source has been modified in a phased manner so as to achieve sub-Doppler resolution. The system has been used to record the hyperfine spectrum of the D2 transitions of Rb and K isotopes. The spectral resolution achieved is ∼ 26 MHz and is adequate to carry out high resolution measurement of isotope shifts and hyperfine structure of various atomic species. The other major advantage of the source is that it requires very small amounts of sample for achieving very good signal to noise ratio. (author)

Use of SSNTD for measuring nuclear reactions

Energy Technology Data Exchange (ETDEWEB)

Bakr, M H [Division of Baic Nucl. Sc., NRC, Atomic Energy Authority Cairo (Egypt)

1997-12-31

Solid state nuclear track detectors (SSNTD) technique in nuclear reactions is reviewed. Special attention is given to the study of Makrofol-E films using a proposed optimum etching solution. The etching rate was 10.5 Mm/ hour. The energy resolution was measured and estimated to be 600 and 400 KeV in the energy ranges 1-2 MeV and 2-3 MeV respectively. Based on these results, the sensitivity threshold for gamma-particles in Makrofol-E is shifted up to 1 MeV, otherwise, there will be no discrimination between the etch - pits of gamma- particles with energies ranging from 0 to 1 MeV. The full angular distribution of the gamma-groups were measured in one run by means of a SSNTD sheel surrounding the target. A scattering chamber designed for gamma-particle angular distribution measurements is described. An example of the influence of energy loss in degrading Al foils in eliminating the energy angle dependence is given. The numerous curves of the range -energy dependence of gamma - particles in Makrofol - E after passing Al foils of different thicknesses are scaled in one schematic normograph. The later simplifies the process of choosing the suitable Al foil thickness or of determining the range- energy relation. The angular distributions of five gamma- groups from the {sup 56} Co (P, gamma) {sup 56} Fe reaction in the proton energy 1.6 -2.4 MeV have been measured using the designed chamber. A Makrofol - E film of 200 Mm thickness was exposed to the reaction products for 5 hours. This time was enough to get the angular distribution for (d/d) in the range 5-72 Mm barn/ster.

Influence of Incomplete Mixing on the OH-Isoprene Reaction in the Lower Troposphere - Measurements Above the Amazon Rain Forest and General Considerations

Science.gov (United States)

Sörgel, M.; Dlugi, R. J. W.; Berger, M.; Mallik, C.; Tsokankunku, A.; Zelger, M.; Acevedo, O. C.; Dias, N. L.; Hofzumahaus, A.; Kesselmeier, J.; Kramm, G.; Marno, D. R.; Martinez, M.; Nölscher, A.; H G, O.; Pfannerstill, E.; Bourtsoukidis, E.; Rohrer, F.; Tauer, S.; Williams, J.; Yanez Serrano, A. M.; Andreae, M. O.; Harder, H.

2017-12-01

Incomplete mixing of reactants in the atmosphere (segregation) causes reduced reaction rates compared to laboratory values derived for well mixed conditions. To adequately determine the actual reaction rates in a variety of natural environments where the distribution of sources and sinks leads to inhomogeneous distribution of reactants, the intensity of segregation (IS) has to be taken into account. Although, there has been considerable progress in modeling IS in the boundary layer within the last 30 years, calculations from direct observations are still sparse as high time resolution and time synchronization are required. OH-radicals are the most important oxidizing agent in the atmosphere, and are therefore regarded as the detergent of the atmosphere, reacting with the majority of atmospheric pollutants and therefore accelerating their removal from the atmosphere. Hence, to understand atmospheric self-cleansing, we need to quantify and understand the budgets (sources and sinks) of OH. As it is a fast reacting compound, for some of its reactants mixing will limit the reaction rate. The reaction of isoprene and OH radicals has gained considerable interest in recent years since large discrepancies between modeled and measured OH have been found mainly in high isoprene environments. This motivated not only laboratory studies on unknown recycling mechanisms for OH in this reaction, but also modeling work and field studies on the effect of segregation on this reaction. We measured OH radicals, isoprene and other species that are either precursors of OH or promote OH recycling (e.g. O3, NOx, HO2, H2O) with high time resolution (1-10 Hz) closely above a rain forest canopy (at 41 m above ground level) at the ATTO (Amazon Tall Tower Observatory) site (02°08'38.8''S, 58°59'59.5''W). The site is characterized by high isoprene (up to 20 ppb) and low NO (50 -500 ppt). Simultaneous measurements of OH and isoprene with high time resolution so far have been sparse. To our

High resolution studies of pion-nucleus reaction mechanism

International Nuclear Information System (INIS)

Morris, C.L.

1983-01-01

Pion inelastic scattering is generally well described as a first order process using the DWIA. This is especially true for a large body of inelastic scattering data to low-lying collective states which is well-described by form factors obtained in (e,e') and the DWIA. Some data for which this model does not work are presented. Higher order reaction mechanisms have been invoked to explain some of these data. However, no model of these second order processes gives a satisfactory explanation of the entire data set. Experimentally, more data for pion-induced transitions to low-spin unnatural-parity states which have been studied by other probes would be useful in sorting out the reaction mechanisms responsible for the anomalous cross sections observed for the 1 + states in 12 C. Theoretically, a consistent evaluation of possible second-order diagrams in inelastic scattering, such as is being attempted for DCX 22 , would be useful

Pyrosequencing™ : A one-step method for high resolution HLA typing

Directory of Open Access Journals (Sweden)

Marincola Francesco M

2003-11-01

Full Text Available Abstract While the use of high-resolution molecular typing in routine matching of human leukocyte antigens (HLA is expected to improve unrelated donor selection and transplant outcome, the genetic complexity of HLA still makes the current methodology limited and laborious. Pyrosequencing™ is a gel-free, sequencing-by-synthesis method. In a Pyrosequencing reaction, nucleotide incorporation proceeds sequentially along each DNA template at a given nucleotide dispensation order (NDO that is programmed into a pyrosequencer. Here we describe the design of a NDO that generates a pyrogram unique for any given allele or combination of alleles. We present examples of unique pyrograms generated from each of two heterozygous HLA templates, which would otherwise remain cis/trans ambiguous using standard sequencing based typing (SBT method. In addition, we display representative data that demonstrate long read and linear signal generation. These features are prerequisite of high-resolution typing and automated data analysis. In conclusion Pyrosequencing is a one-step method for high resolution DNA typing.

Benchmarking NaI(Tl) Electron Energy Resolution Measurements

International Nuclear Information System (INIS)

Mengesha, Wondwosen; Valentine, J D.

2002-01-01

A technique for validating electron energy resolution results measured using the modified Compton coincidence technique (MCCT) has been developed. This technique relies on comparing measured gamma-ray energy resolution with calculated values that were determined using the measured electron energy resolution results. These gamma-ray energy resolution calculations were based on Monte Carlo photon transport simulations, the measured NaI(Tl) electron response, a simplified cascade sequence, and the measured electron energy resolution results. To demonstrate this technique, MCCT-measured NaI(Tl) electron energy resolution results were used along with measured gamma-ray energy resolution results from the same NaI(Tl) crystal. Agreement to within 5% was observed for all energies considered between the calculated and measured gamma-ray energy resolution results for the NaI(Tl) crystal characterized. The calculated gamma-ray energy resolution results were also compared with previously published gamma-ray energy resolution measurements with good agreement (<10%). In addition to describing the validation technique that was developed in this study and the results, a brief review of the electron energy resolution measurements made using the MCCT is provided. Based on the results of this study, it is believed that the MCCT-measured electron energy resolution results are reliable. Thus, the MCCT and this validation technique can be used in the future to characterize the electron energy resolution of other scintillators and to determine NaI(Tl) intrinsic energy resolution

High-Resolution Mass Spectrometers

Science.gov (United States)

Marshall, Alan G.; Hendrickson, Christopher L.

2008-07-01

Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

Combined local current distribution measurements and high resolution neutron radiography of operating direct methanol fuel cells

Energy Technology Data Exchange (ETDEWEB)

Schroeder, Alexander; Wippermann, Klaus [Forschungszentrum Juelich GmbH (Germany). Inst. of Energy Research, IEF-3: Fuel Cells; Sanders, Tilman [RWTH Aachen (DE). Inst. for Power Electronics and Electrical Drives (ISEA); Arlt, Tobias [Helmholtz Centre Berlin (Germany). Inst. for Applied Materials

2010-07-01

Neutron radiography allows the investigation of the local fluid distribution in direct methanol fuel cells (DMFCs) under operating conditions. Spatial resolutions in the order of some tens of micrometers at the full test cell area are achieved. This offers the possibility to study practice-oriented, large stack cells with an active area of several hundred cm{sup 2} as well as specially designed, small test cells with an area of some cm{sup 2}. Combined studies of high resolution neutron radiography and segmented cell measurements are especially valuable, because they enable a correlation of local fluid distribution and local performance [1, 2]. The knowledge of this interdependency is essential to optimise the water management and performance respecting a homogeneous fluid, current and temperature distribution and to achieve high performance and durability of DMFCs. (orig.)

A high-resolution study of the sup 20 Ne( sup 3 He,t) sup 20 Na reaction and the sup 19 Ne(p,. gamma. ) sup 20 Na reaction rate

Energy Technology Data Exchange (ETDEWEB)

Smith, M S; Magnus, P V; Hahn, K I; Howard, A J; Parker, P D [A.W. Wright Nuclear Structure Lab., Yale Univ., New Haven, CT (United States); Champagne, A E; Mao, Z Q [Dept. of Physics, Princeton Univ., NJ (United States)

1992-01-13

A high-precision measurement of the {sup 20}Ne({sup 3}He,t){sup 20}Na reaction has been made using implanted {sup 20}Ne transmission targets to obtain pertinent information on the low-energy resonances in the {sup 19}Ne(p,{gamma}){sup 20}Na reaction. Resonance energies (447{+-}5, 658{+-}5, 787{+-}5, and 857{+-}5 keV) and upper limits on total intrinsic widths (<10, <6, <10, and <16 keV) have been measured for four excited states above the 2.199 MeV proton threshold in {sup 20}Na. The stellar {sup 19}Ne(p,{gamma}){sup 20}Na reaction rate is calculated for temperatures between 1x10{sup 8} and 1x10{sup 9} K. When combined with a recent study of the {sup 15}O({alpha},{gamma}){sup 19}Ne reaction, a new estimate is made of the conditions required for breakout from the Hot CNO cylce to the rapid proton capture process. (orig.).

Isotopic composition of neon in the galactic cosmic rays: a high resolution measurement

International Nuclear Information System (INIS)

Greiner, D.E.; Wiedenbeck, M.E.; Bieser, F.S.; Crawford, H.J.; Heckman, H.H.; Lindstrom, P.J.

1979-06-01

A measurement of the isotopic composition of galactic cosmic ray neon in the energy range 70 to 260 MeV/amu has been made using the U.C. Berkeley HKH instrument aboard ISEE-3. A combination of high resolution and good statistical accuracy makes possible a precise determination of the local interplanetary neon composition. We find 22 Ne/ 20 Ne = 0.64 +- 0.07 and 21 Ne/ 20 Ne < 0.30 in local interplanetary space. These ratios, when interpreted in using standard galactic propagation and solar modulation models, yield cosmic ray source abundances which are inconsistent with a solar-like source composition

Constraining Stochastic Parametrisation Schemes Using High-Resolution Model Simulations

Science.gov (United States)

Christensen, H. M.; Dawson, A.; Palmer, T.

2017-12-01

Stochastic parametrisations are used in weather and climate models as a physically motivated way to represent model error due to unresolved processes. Designing new stochastic schemes has been the target of much innovative research over the last decade. While a focus has been on developing physically motivated approaches, many successful stochastic parametrisation schemes are very simple, such as the European Centre for Medium-Range Weather Forecasts (ECMWF) multiplicative scheme `Stochastically Perturbed Parametrisation Tendencies' (SPPT). The SPPT scheme improves the skill of probabilistic weather and seasonal forecasts, and so is widely used. However, little work has focused on assessing the physical basis of the SPPT scheme. We address this matter by using high-resolution model simulations to explicitly measure the `error' in the parametrised tendency that SPPT seeks to represent. The high resolution simulations are first coarse-grained to the desired forecast model resolution before they are used to produce initial conditions and forcing data needed to drive the ECMWF Single Column Model (SCM). By comparing SCM forecast tendencies with the evolution of the high resolution model, we can measure the `error' in the forecast tendencies. In this way, we provide justification for the multiplicative nature of SPPT, and for the temporal and spatial scales of the stochastic perturbations. However, we also identify issues with the SPPT scheme. It is therefore hoped these measurements will improve both holistic and process based approaches to stochastic parametrisation. Figure caption: Instantaneous snapshot of the optimal SPPT stochastic perturbation, derived by comparing high-resolution simulations with a low resolution forecast model.

A simple and rapid method for high-resolution visualization of single-ion tracks

Directory of Open Access Journals (Sweden)

Masaaki Omichi

2014-11-01

Full Text Available Prompt determination of spatial points of single-ion tracks plays a key role in high-energy particle induced-cancer therapy and gene/plant mutations. In this study, a simple method for the high-resolution visualization of single-ion tracks without etching was developed through the use of polyacrylic acid (PAA-N, N’-methylene bisacrylamide (MBAAm blend films. One of the steps of the proposed method includes exposure of the irradiated films to water vapor for several minutes. Water vapor was found to promote the cross-linking reaction of PAA and MBAAm to form a bulky cross-linked structure; the ion-track scars were detectable at a nanometer scale by atomic force microscopy. This study demonstrated that each scar is easily distinguishable, and the amount of generated radicals of the ion tracks can be estimated by measuring the height of the scars, even in highly dense ion tracks. This method is suitable for the visualization of the penumbra region in a single-ion track with a high spatial resolution of 50 nm, which is sufficiently small to confirm that a single ion hits a cell nucleus with a size ranging between 5 and 20 μm.

A simple and rapid method for high-resolution visualization of single-ion tracks

Energy Technology Data Exchange (ETDEWEB)

Omichi, Masaaki [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan); Center for Collaborative Research, Anan National College of Technology, Anan, Tokushima 774-0017 (Japan); Choi, Wookjin; Sakamaki, Daisuke; Seki, Shu, E-mail: seki@chem.eng.osaka-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan); Tsukuda, Satoshi [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Sugimoto, Masaki [Japan Atomic Energy Agency, Takasaki Advanced Radiation Research Institute, Gunma, Gunma 370-1292 (Japan)

2014-11-15

Prompt determination of spatial points of single-ion tracks plays a key role in high-energy particle induced-cancer therapy and gene/plant mutations. In this study, a simple method for the high-resolution visualization of single-ion tracks without etching was developed through the use of polyacrylic acid (PAA)-N, N’-methylene bisacrylamide (MBAAm) blend films. One of the steps of the proposed method includes exposure of the irradiated films to water vapor for several minutes. Water vapor was found to promote the cross-linking reaction of PAA and MBAAm to form a bulky cross-linked structure; the ion-track scars were detectable at a nanometer scale by atomic force microscopy. This study demonstrated that each scar is easily distinguishable, and the amount of generated radicals of the ion tracks can be estimated by measuring the height of the scars, even in highly dense ion tracks. This method is suitable for the visualization of the penumbra region in a single-ion track with a high spatial resolution of 50 nm, which is sufficiently small to confirm that a single ion hits a cell nucleus with a size ranging between 5 and 20 μm.

Quantifying the Uncertainty in High Spatial and Temporal Resolution Synthetic Land Surface Reflectance at Pixel Level Using Ground-Based Measurements

Science.gov (United States)

Kong, J.; Ryu, Y.

2017-12-01

Algorithms for fusing high temporal frequency and high spatial resolution satellite images are widely used to develop dense time-series land surface observations. While many studies have revealed that the synthesized frequent high spatial resolution images could be successfully applied in vegetation mapping and monitoring, validation and correction of fused images have not been focused than its importance. To evaluate the precision of fused image in pixel level, in-situ reflectance measurements which could account for the pixel-level heterogeneity are necessary. In this study, the synthetic images of land surface reflectance were predicted by the coarse high-frequency images acquired from MODIS and high spatial resolution images from Landsat-8 OLI using the Flexible Spatiotemporal Data Fusion (FSDAF). Ground-based reflectance was measured by JAZ Spectrometer (Ocean Optics, Dunedin, FL, USA) on rice paddy during five main growth stages in Cheorwon-gun, Republic of Korea, where the landscape heterogeneity changes through the growing season. After analyzing the spatial heterogeneity and seasonal variation of land surface reflectance based on the ground measurements, the uncertainties of the fused images were quantified at pixel level. Finally, this relationship was applied to correct the fused reflectance images and build the seasonal time series of rice paddy surface reflectance. This dataset could be significant for rice planting area extraction, phenological stages detection, and variables estimation.

High-resolution γ-ray spectroscopy of hyperfragments produced by stopped K- reactions

International Nuclear Information System (INIS)

Miwa, K.; Tanida, K.; Akikawa, H.; Fukao, Y.; Hiyama, E.; Hotchi, H.; Imai, K.; Miura, Y.; Mizunuma, K.; Nakamura, S.N.; Niiyama, M.; Ota, S.; Saha, P.K.; Takahashi, H.; Takahashi, T.; Tamura, H.; Terashima, S.; Togawa, M.; Ukai, M.

2005-01-01

We performed an experiment to measure γ rays of hyperfragments produced by stopped K- reactions on light (A= 1/2+) in 7 Λ Li with 10 B, 11 B and 12 C targets and obtained the γ-ray intensity to be (7.5+/-1.6)x10-4 per stopped K- for 10 B target. In addition, a candidate for a new hypernuclear γ ray was observed. These results show that this method is quite suitable for the systematic study of hypernuclei

High-resolution Tangential AXUV Arrays for Radiated Power Density Measurements on NSTX-U

Energy Technology Data Exchange (ETDEWEB)

Delgado-Aparicio, L [PPPL; Bell, R E [PPPL; Faust, I [MIT; Tritz, K [The Johns Hopkins University, Baltimore, MD, 21209, USA; Diallo, A [PPPL; Gerhardt, S P [PPPL; Kozub, T A [PPPL; LeBlanc, B P [PPPL; Stratton, B C [PPPL

2014-07-01

Precise measurements of the local radiated power density and total radiated power are a matter of the uttermost importance for understanding the onset of impurity-induced instabilities and the study of particle and heat transport. Accounting of power balance is also needed for the understanding the physics of various divertor con gurations for present and future high-power fusion devices. Poloidal asymmetries in the impurity density can result from high Mach numbers and can impact the assessment of their flux-surface-average and hence vary the estimates of P[sub]rad (r, t) and (Z[sub]eff); the latter is used in the calculation of the neoclassical conductivity and the interpretation of non-inductive and inductive current fractions. To this end, the bolometric diagnostic in NSTX-U will be upgraded, enhancing the midplane coverage and radial resolution with two tangential views, and adding a new set of poloidally-viewing arrays to measure the 2D radiation distribution. These systems are designed to contribute to the near- and long-term highest priority research goals for NSTX-U which will integrate non-inductive operation at reduced collisionality, with high-pressure, long energy-confinement-times and a divertor solution with metal walls.

ANL high resolution injector

International Nuclear Information System (INIS)

Minehara, E.; Kutschera, W.; Hartog, P.D.; Billquist, P.

1985-01-01

The ANL (Argonne National Laboratory) high-resolution injector has been installed to obtain higher mass resolution and higher preacceleration, and to utilize effectively the full mass range of ATLAS (Argonne Tandem Linac Accelerator System). Preliminary results of the first beam test are reported briefly. The design and performance, in particular a high-mass-resolution magnet with aberration compensation, are discussed. 7 refs., 5 figs., 2 tabs

Rapid detection of the positive side reactions in vanadium flow batteries

International Nuclear Information System (INIS)

Liu, Le; Li, Zhaohua; Xi, Jingyu; Zhou, Haipeng; Wu, Zenghua; Qiu, Xinping

2017-01-01

Highlights: • A method for rapid measurement of the positive side reactions in VFB is presented. • The SOC of positive electrolytes can be detected with resolution of 0.002%. • Side reaction ratios at different charge currents, flow rates are obtained. - Abstract: We present an optical detection method for rapid measurement of the positive side reactions in vanadium flow batteries (VFB). By measuring the transmittance of the positive electrolytes in VFB, the states of charge (SOC) of the positive electrolytes can be detected at very high resolution (better than 0.002% in the SOC range from 98% to 100%), due to the nonlinear transmittance spectra caused by the interactions between V(IV) and V(V) ions. The intensity of the positive side reactions of a VFB can be rapidly measured by a few steps, attributing to the fact that the positive side reactions occur only during the high voltage charging process. The ratios of the positive side reactions at different charge currents and different flow rates are obtained while causing no damage to the battery. This optical detection method can rapidly determine the optimal parameters of the VFB system, providing new means for studying the electrochemical reactions in the VFB system and rapid test in industrial production of VFBs.

High temperature reactions between molybdenum and metal halides

International Nuclear Information System (INIS)

Boeroeczki, A.; Dobos, G.; Josepovits, V.K.; Hars, Gy.

2006-01-01

Good colour rendering properties, high intensity and efficacy are of vital importance for high-end lighting applications. These requirements can be achieved by high intensity discharge lamps doped with different metal halide additives (metal halide lamps). To improve their reliability, it is very important to understand the different failure processes of the lamps. In this paper, the corrosion reactions between different metal halides and the molybdenum electrical feed-through electrode are discussed. The reactions were studied in the feed-through of real lamps and on model samples too. X-ray photoelectron spectroscopy (XPS) was used to establish the chemical states. In case of the model samples we have also used atomic absorption spectroscopy (AAS) to measure the reaction product amounts. Based on the measurement results we were able to determine the most corrosive metal halide components and to understand the mechanism of the reactions

Measurements of activation cross-sections for the 101Ru(n,p)101Tc reaction for neutrons with energies between 13 and 15 MeV

International Nuclear Information System (INIS)

Junhua Luo; Peking University, Beijing; Jiuning Han; Suhong Ge; Zhenlai Liu; Guihua Sun; Rong Liu; Li Jiang

2013-01-01

In this study, activation cross-sections were measured for the 101 Ru(n,p) 101 Tc reaction at three different neutron energies from 13.5 to 14.8 MeV. The fast neutrons were produced via the 3 H(d,n) 4 He reaction on K-400 neutron generator. Induced gamma activities were measured by a high-resolution gamma-ray spectrometer with high-purity germanium detector. Measurements were corrected for gamma-ray attenuations, random coincidence (pile-up), dead time and fluctuation of neutron flux. The data for 101 Ru(n,p) 101 Tc reaction cross-sections are reported to be 15.7 ± 2.0, 18.4 ± 2.7 and 22.0 ± 2.4 mb at 13.5 ± 0.2, 14.1 ± 0.2, and 14.8 ± 0.2 MeV incident neutron energies, respectively. Results were compared with the previous works. (author)

Enhanced emission of high-energy photons perpendicular to the reaction plane in α+Th reactions

International Nuclear Information System (INIS)

Tegner, P.; Marianski, B.; Morsch, H.P.; Rogge, M.; Bargholtz, C.; Decowski, P.; Zemlo, L.

1991-01-01

High-energy photon and neutron emission has been measured in coincidence with fission fragments in α+ 232 Th reactions at 170 MeV. From measurements parallel and perpendicular to the fission plane, anisotropies relative to the reaction plane were determined. The in-plane/out-of-plane intensity ratio is 0.72(7) for photons with energies above 20 MeV and 11(3) for neutrons at 35 MeV. The result for high-energy photons can be explained by nucleon-nucleon bremsstrahlung if the initial flow of nucleons has a correlation to the reaction plane similar to the one observed for fast neutrons

Security camera resolution measurements: Horizontal TV lines versus modulation transfer function measurements.

Energy Technology Data Exchange (ETDEWEB)

Birch, Gabriel Carisle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Griffin, John Clark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-01-01

The horizontal television lines (HTVL) metric has been the primary quantity used by division 6000 related to camera resolution for high consequence security systems. This document shows HTVL measurements are fundamen- tally insufficient as a metric to determine camera resolution, and propose a quantitative, standards based methodology by measuring the camera system modulation transfer function (MTF), the most common and accepted metric of res- olution in the optical science community. Because HTVL calculations are easily misinterpreted or poorly defined, we present several scenarios in which HTVL is frequently reported, and discuss their problems. The MTF metric is discussed, and scenarios are presented with calculations showing the application of such a metric.

Detectors for high resolution dynamic pet

International Nuclear Information System (INIS)

Derenzo, S.E.; Budinger, T.F.; Huesman, R.H.

1983-05-01

This report reviews the motivation for high spatial resolution in dynamic positron emission tomography of the head and the technical problems in realizing this objective. We present recent progress in using small silicon photodiodes to measure the energy deposited by 511 keV photons in small BGO crystals with an energy resolution of 9.4% full-width at half-maximum. In conjunction with a suitable phototube coupled to a group of crystals, the photodiode signal to noise ratio is sufficient for the identification of individual crystals both for conventional and time-of-flight positron tomography

Simultaneous observations of structure function parameter of refractive index using a high-resolution radar and the DataHawk small airborne measurement system

Science.gov (United States)

Scipión, Danny E.; Lawrence, Dale A.; Milla, Marco A.; Woodman, Ronald F.; Lume, Diego A.; Balsley, Ben B.

2016-09-01

The SOUSY (SOUnding SYstem) radar was relocated to the Jicamarca Radio Observatory (JRO) near Lima, Peru, in 2000, where the radar controller and acquisition system were upgraded with state-of-the-art parts to take full advantage of its potential for high-resolution atmospheric sounding. Due to its broad bandwidth (4 MHz), it is able to characterize clear-air backscattering with high range resolution (37.5 m). A campaign conducted at JRO in July 2014 aimed to characterize the lower troposphere with a high temporal resolution (8.1 Hz) using the DataHawk (DH) small unmanned aircraft system, which provides in situ atmospheric measurements at scales as small as 1 m in the lower troposphere and can be GPS-guided to obtain measurements within the beam of the radar. This was a unique opportunity to make coincident observations by both systems and to directly compare their in situ and remotely sensed parameters. Because SOUSY only points vertically, it is only possible to retrieve vertical radar profiles caused by changes in the refractive index within the resolution volume. Turbulent variations due to scattering are described by the structure function parameter of refractive index Cn2. Profiles of Cn2 from the DH are obtained by combining pressure, temperature, and relative humidity measurements along the helical trajectory and integrated at the same scale as the radar range resolution. Excellent agreement is observed between the Cn2 estimates obtained from the DH and SOUSY in the overlapping measurement regime from 1200 m up to 4200 m above sea level, and this correspondence provides the first accurate calibration of the SOUSY radar for measuring Cn2.

Cross sections measurement of isomeric states formation in nuclear reactions induced by neutrons of 14 Mev and comparison with statistical theories

International Nuclear Information System (INIS)

El Bardouni, T.

1989-01-01

Excitation functions of some (n,2n), (n,p) and (n,alpha) reactions on isotopes taken in different mass regions have been measured around 14 Mev. We give more interest to reactions leading to residual nucleus in isomeric states. Quasi-monoenergetic neutrons are produced via the T(d,n)alpha reaction and activation technique is combined to high resolution gamma-ray spectrometry. In the measurement of samples activities, we have scanned carefully the different origins of uncertainties and taken into account all necessary corrections. We have also carried out a detailed study about the nuclear reactions theory (compound nucleus and Geometry Dependent Hybrid Models) in order to compare our measurements results and theoretical calculations. The EMPIRE code (based on compound nucleus and Geometry Dependent Hybrid Models), that we have adapted on IBM Personal Computer, allows us to reproduce with great satisfaction the measured excitation functions without adjusting the models parameters. So we can rely on the EMPIRE code, as it is done in its work, in the prediction of some nuclear reactions excitation functions that cannot be determined by means of activation technique and gamma-ray spectrometry. 88 refs., 43 figs., 16 tabs., 1 chart. (author)

Direct analysis of prostaglandin-E2 and -D2 produced in an inflammatory cell reaction and its application for activity screening and potency evaluation using turbulent flow chromatography liquid chromatography-high resolution mass spectrometry.

Science.gov (United States)

Shin, Jeong-Sook; Peng, Lei; Kang, Kyungsu; Choi, Yongsoo

2016-09-09

Direct analysis of prostaglandin-E2 (PGE2) and -D2 (PGD2) produced from a RAW264.7 cell-based reaction was performed by liquid chromatography high-resolution mass spectrometry (LC-HRMS), which was online coupled with turbulent flow chromatography (TFC). The capability of this method to accurately measure PG levels in cell reaction medium containing cytokines or proteins as a reaction byproduct was cross-validated by two conventional methods. Two methods, including an LC-HRMS method after liquid-liquid extraction (LLE) of the sample and a commercial PGE2 enzyme-linked immunosorbent assay (ELISA), showed PGE2 and/or PGD2 levels almost similar to those obtained by TFC LC-HRMS over the reaction time after LPS stimulation. After the cross-validation, significant analytical throughputs, allowing simultaneous screening and potency evaluation of 80 natural products including 60 phytochemicals and 20 natural product extracts for the inhibition of the PGD2 produced in the cell-based inflammatory reaction, were achieved using the TFC LC-HRMS method developed. Among the 60 phytochemicals screened, licochalcone A and formononetin inhibited PGD2 production the most with IC50 values of 126 and 151nM, respectively. For a reference activity, indomethacin and diclofenac were used, measuring IC50 values of 0.64 and 0.21nM, respectively. This method also found a butanol extract of Akebia quinata Decne (AQ) stem as a promising natural product for PGD2 inhibition. Direct and accurate analysis of PGs in the inflammatory cell reaction using the TFC LC-HRMS method developed enables the high-throughput screening and potency evaluation of as many as 320 samples in less than 48h without changing a TFC column. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthetic Pulse Dilation - PMT Model for high bandwidth gamma measurements

Science.gov (United States)

Geppert-Kleinrath, H.; Herrmann, H. W.; Kim, Y. H.; Zylstra, A. B.; Meaney, K. D.; Lopez, F. E.; Khater, H.; Horsfield, C. J.; Gales, S.; Leatherland, A.; Hilsabeck, T.; Kilkenny, J. D.; Hares, J. D.; Dymoke-Bradshaw, T.; Milnes, J.

2017-10-01

The Cherenkov mechanism used in Gas Cherenkov Detectors (GCD) is exceptionally fast. However, the temporal resolution of GCDs, such as the Gamma Reaction History diagnostic (GRH), is limited by the current state-of-the-art photomultiplier tube (PMT) to 100 ps. The new pulse dilation - PMT (PD-PMT) for NIF allows for a temporal resolution comparable to that of the gas cell, or of 10ps. Enhanced resolution will contribute to the quest for ignition in a crucial way through precision measurement of reaction history and areal density (ρ R) history, leading to better constrained models. Features such as onset of alpha heating, shock reverberations and burn truncation due to dynamically evolving failure modes will become visible for the first time. PD-PMT will be deployed on GCD-3 at NIF in 2018. Our synthetic PD-PMT model evaluates the capabilities of these future measurements, as well as minimum yield requirements for measurements performed in a well at 3.9 m from target chamber center (TCC), and within a diagnostic inserter at 0.2m from TCC.

Free radicals. High-resolution spectroscopy and molecular structure

International Nuclear Information System (INIS)

Hirota, E.

1983-01-01

High-resolution, high-sensitivity spectroscopy using CW laser and microwave sources has been applied to free radicals and transient molecules to establish their existence and to explore their properties in detail. The radicals studied were mainly generated by discharge-induced reactions. A few molecules are used as typical examples to illustrate the results so far obtained. The molecular and electronic structures of free radicals, intramolecular motions of large amplitudes in some labile molecules, and metastable electronic states of carbenes are given special emphasis. The significance of the present spectroscopic results in other related fields such as astronomy and atmospheric chemistry is stressed. 4 figures, 3 tables

High-resolution nuclear magnetic resonance measurements in inhomogeneous magnetic fields: A fast two-dimensional J-resolved experiment

Energy Technology Data Exchange (ETDEWEB)

Huang, Yuqing; Cai, Shuhui; Yang, Yu; Sun, Huijun; Lin, Yanqin, E-mail: linyq@xmu.edu.cn, E-mail: chenz@xmu.edu.cn; Chen, Zhong, E-mail: linyq@xmu.edu.cn, E-mail: chenz@xmu.edu.cn [Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen 361005 (China); Lin, Yung-Ya [Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095 (United States)

2016-03-14

High spectral resolution in nuclear magnetic resonance (NMR) is a prerequisite for achieving accurate information relevant to molecular structures and composition assignments. The continuous development of superconducting magnets guarantees strong and homogeneous static magnetic fields for satisfactory spectral resolution. However, there exist circumstances, such as measurements on biological tissues and heterogeneous chemical samples, where the field homogeneity is degraded and spectral line broadening seems inevitable. Here we propose an NMR method, named intermolecular zero-quantum coherence J-resolved spectroscopy (iZQC-JRES), to face the challenge of field inhomogeneity and obtain desired high-resolution two-dimensional J-resolved spectra with fast acquisition. Theoretical analyses for this method are given according to the intermolecular multiple-quantum coherence treatment. Experiments on (a) a simple chemical solution and (b) an aqueous solution of mixed metabolites under externally deshimmed fields, and on (c) a table grape sample with intrinsic field inhomogeneity from magnetic susceptibility variations demonstrate the feasibility and applicability of the iZQC-JRES method. The application of this method to inhomogeneous chemical and biological samples, maybe in vivo samples, appears promising.

A high resolution large dynamic range TDC circuit implementation

International Nuclear Information System (INIS)

Lei Wuhu; Liu Songqiu; Ye Weiguo; Han Hui; Li Pengyu

2003-01-01

Time measurement technology is usually used in nuclear experimentation. There are many methods of time measurement. The implementation method of Time to Digital Conversion (TDC) by means of electronic is a classical technology. The range and resolution of TDC is different according with different usage. A wide range and high resolution TDC circuit, including its theory and implementation way, is introduced in this paper. The test result is also given. (authors)

A high resolution large dynamic range TDC circuit implementation

International Nuclear Information System (INIS)

Lei Wuhu; Liu Songqiu; Li Pengyu; Han Hui; Ye Yanlin

2005-01-01

Time measurement technology is usually used in nuclear experimentation. There are many methods of time measurement. The implementation method of Time to Digital Conversion (TDC) by means of electronics is a classical technology. The range and resolution of TDC is different according with different usage. A wide range and high resolution TDC circuit, including its theory and implementation way, is introduced in this paper. The test result is also given. (authors)

Comparison of measured and calculated reaction rate distributions in an scwr-like test lattice

Energy Technology Data Exchange (ETDEWEB)

Raetz, Dominik, E-mail: dominik.raetz@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Jordan, Kelly A., E-mail: kelly.jordan@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Murphy, Michael F., E-mail: mike.murphy@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Perret, Gregory, E-mail: gregory.perret@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Chawla, Rakesh, E-mail: rakesh.chawla@psi.ch [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, EPFL (Switzerland)

2011-04-15

High resolution gamma-ray spectroscopy measurements were performed on 61 rods of an SCWR-like fuel lattice, after irradiation in the central test zone of the PROTEUS zero-power research reactor at the Paul Scherrer Institute in Switzerland. The derived reaction rates are the capture rate in {sup 238}U (C{sub 8}) and the total fission rate (F{sub tot}), and also the reaction rate ratio C{sub 8}/F{sub tot}. Each of these has been mapped rod-wise on the lattice and compared to calculated results from whole-reactor Monte Carlo simulations with MCNPX. Ratios of calculated to experimental values (C/E's) have been assessed for the C{sub 8}, F{sub tot} and C{sub 8}/F{sub tot} distributions across the lattice. These C/E's show excellent agreement between the calculations and the measurements. For the {sup 238}U capture rate distribution, the 1{sigma} level in the comparisons corresponds to an uncertainty of {+-}0.8%, while for the total fission rate the corresponding value is {+-}0.4%. The uncertainty for C{sub 8}/F{sub tot}, assessed as a reaction rate ratio characterizing each individual rod position in the test lattice, is significantly higher at {+-}2.2%. To determine the reproducibility of these results, the measurements were performed twice, once in 2006 and again in 2009. The agreement between these two measurement sets is within the respective statistical uncertainties.

High temperature and high resolution uv photoelectron spectroscopy using supersonic molecular beams

International Nuclear Information System (INIS)

Wang, Lai-Sheng; Reutt-Robey, J.E.; Niu, B.; Lee, Y.T.; Shirley, D.A.

1989-07-01

A high temperature molecular beam source with electron bombardment heating has been built for high resolution photoelectron spectroscopic studies of high temperature species and clusters. This source has the advantages of: producing an intense, continuous, seeded molecular beam, eliminating the interference of the heating mechanism from the photoelectron measurement. Coupling the source with our hemispherical electron energy analyzer, we can obtain very high resolution HeIα (584 angstrom) photoelectron spectra of high temperature species. Vibrationally-resolved photoelectron spectra of PbSe, As 2 , As 4 , and ZnCl 2 are shown to demonstrate the performance of the new source. 25 refs., 8 figs., 1 tab

Nanometer-scale displacement measurement with high resolution using dual cavity Fabry-Pérot interferometer for biomimetic robots.

Science.gov (United States)

Lee, Jin-Hyuk; Kim, Dae-Hyun

2014-10-01

A sensor of a biomimetic robot has to measure very small environmental changes such as, nanometer scale strains or displacements. Fiber optic sensor can be also one of candidates for the biomimetic sensor because the sensor is like thread and the shape of the sensor is similar to muscle fiber. A fiber optic interferometer, which is an optical-based sensor, can measure displacement precisely, so such device has been widely studied for the measurement of displacement on a nanometer-scale. Especially, a Quadrature Phase-Shifted Fiber Fabry-Pérot interferometer (QPS-FFPI) uses phase-information for this measurement, allowing it to provide a precision result with high resolution. In theory, the QPS-FFPI generates two sinusoidal signals of which the phase difference should be 90 degrees for the exact measurement of the displacement. In order to guarantee the condition of the phase difference, the relative adjustment of the cavities of the optical fibers is required. However, with such precise adjustment it is very hard to fix the proper difference of the two cavities for quadrature-phase-shifting. In this paper, a dual-cavity FFPI is newly proposed to measure the displacement on a nanometer-scale with a specific type of signal processing. In the signal processing, a novel phase-compensation algorithm is applied to force the phase difference to be exactly 90 degrees without any physical adjustment. As a result, the paper shows that the phase-compensated dual-cavity FFPI can effectively measure nanometer-scale displacement with high resolution under dynamic conditions.

Oxygen 18 concentration profile measurements near the surface by 18O(p,α)15N resonance reaction

International Nuclear Information System (INIS)

Amsel, G.; David, D.

1975-01-01

The method of spectrum reduction in nuclear reaction microanalysis does not allow to obtain depth resolutions better than the order of 2000A. Resolutions of the order of 200A may be obtained by using the narrow resonance technique, when applied to thin films. The latter technique was extended to thick targets, with deep concentration profiles presenting a sharp gradient near the surface. This method is presented and illustrated by the study of 18 O profiles in oxygen diffusion measurements in growing ZrO 2 , using the 629keV resonance of the reaction 18 O(p,α) 15 N [fr

High resolution ultrasonic densitometer

International Nuclear Information System (INIS)

Dress, W.B.

1983-01-01

The velocity of torsional stress pulses in an ultrasonic waveguide of non-circular cross section is affected by the temperature and density of the surrounding medium. Measurement of the transit times of acoustic echoes from the ends of a sensor section are interpreted as level, density, and temperature of the fluid environment surrounding that section. This paper examines methods of making these measurements to obtain high resolution, temperature-corrected absolute and relative density and level determinations of the fluid. Possible applications include on-line process monitoring, a hand-held density probe for battery charge state indication, and precise inventory control for such diverse fluids as uranium salt solutions in accountability storage and gasoline in service station storage tanks

Simultaneous observations of structure function parameter of refractive index using a high-resolution radar and the DataHawk small airborne measurement system

Directory of Open Access Journals (Sweden)

D. E. Scipión

2016-09-01

Full Text Available The SOUSY (SOUnding SYstem radar was relocated to the Jicamarca Radio Observatory (JRO near Lima, Peru, in 2000, where the radar controller and acquisition system were upgraded with state-of-the-art parts to take full advantage of its potential for high-resolution atmospheric sounding. Due to its broad bandwidth (4 MHz, it is able to characterize clear-air backscattering with high range resolution (37.5 m. A campaign conducted at JRO in July 2014 aimed to characterize the lower troposphere with a high temporal resolution (8.1 Hz using the DataHawk (DH small unmanned aircraft system, which provides in situ atmospheric measurements at scales as small as 1 m in the lower troposphere and can be GPS-guided to obtain measurements within the beam of the radar. This was a unique opportunity to make coincident observations by both systems and to directly compare their in situ and remotely sensed parameters. Because SOUSY only points vertically, it is only possible to retrieve vertical radar profiles caused by changes in the refractive index within the resolution volume. Turbulent variations due to scattering are described by the structure function parameter of refractive index Cn2. Profiles of Cn2 from the DH are obtained by combining pressure, temperature, and relative humidity measurements along the helical trajectory and integrated at the same scale as the radar range resolution. Excellent agreement is observed between the Cn2 estimates obtained from the DH and SOUSY in the overlapping measurement regime from 1200 m up to 4200 m above sea level, and this correspondence provides the first accurate calibration of the SOUSY radar for measuring Cn2.

Classification of high resolution satellite images

OpenAIRE

Karlsson, Anders

2003-01-01

In this thesis the Support Vector Machine (SVM)is applied on classification of high resolution satellite images. Sveral different measures for classification, including texture mesasures, 1st order statistics, and simple contextual information were evaluated. Additionnally, the image was segmented, using an enhanced watershed method, in order to improve the classification accuracy.

High-resolution smile measurement and control of wavelength-locked QCW and CW laser diode bars

Science.gov (United States)

Rosenkrantz, Etai; Yanson, Dan; Klumel, Genady; Blonder, Moshe; Rappaport, Noam; Peleg, Ophir

2018-02-01

High-power linewidth-narrowed applications of laser diode arrays demand high beam quality in the fast, or vertical, axis. This requires very high fast-axis collimation (FAC) quality with sub-mrad angular errors, especially where laser diode bars are wavelength-locked by a volume Bragg grating (VBG) to achieve high pumping efficiency in solid-state and fiber lasers. The micron-scale height deviation of emitters in a bar against the FAC lens causes the so-called smile effect with variable beam pointing errors and wavelength locking degradation. We report a bar smile imaging setup allowing FAC-free smile measurement in both QCW and CW modes. By Gaussian beam simulation, we establish optimum smile imaging conditions to obtain high resolution and accuracy with well-resolved emitter images. We then investigate the changes in the smile shape and magnitude under thermal stresses such as variable duty cycles in QCW mode and, ultimately, CW operation. Our smile measurement setup provides useful insights into the smile behavior and correlation between the bar collimation in QCW mode and operating conditions under CW pumping. With relaxed alignment tolerances afforded by our measurement setup, we can screen bars for smile compliance and potential VBG lockability prior to assembly, with benefits in both lower manufacturing costs and higher yield.

Study on a high resolution positron emission tomography scanner for brain study

International Nuclear Information System (INIS)

Nohara, N.; Tomitani, T.; Yamamoto, M.; Murayama, H.; Tanaka, E.

1990-01-01

The spatial resolution of positron emission tomography (PET) scanners is usually limited by the finite size of crystals such as bismuth germanate (BGO). To attain high resolution as well as high sensitivity, it is essential to use a large number of small BGO crystals arranged in close-packing on circular rings. In developing high resolution PET scanners, however, there are two physical factors limiting the spatial resolution. One is the finite range of positrons before annihilation and the other the deviation from 180 degrees of annihilation photons. The effect of the factors on the spatial resolution has been evaluated for positron-emitting sources as a function of detector ring radius. A high resolution PET scanner has been developed for brain study, aiming to have spatial resolutions as high as less than 4-mm FWHM in tomographic plane and less than 6-mm FWHM in axial direction at the detector ring center. For the goal of the high resolutions a multi-segment type of photomultiplier tubes has been specially designed and developed, which allows one tube to be directly coupled by four BGO crystals. The scanner consists of five detector rings of 47-cm in diameter, using all 1200 BGO crystals each measuring 5 mm x 12 mm x 30 mm. The scanner provides simultaneous 9 images by combination of in-plane and cross-plane, offering a 24-cm dia. x7.4-cm field-of-view. Physical performance of the scanner was investigated. At the ring center, the spatial resolution in the tomographic plane was measured to be 3.5-mm FWHM. The axial resolution was measured to be 5.7-mm FWHM for in-plane and 5.3-mm FWHM for cross-plane. Sensitivity for a 20-cm dia. uniform source was measured to be 9.5 kcps/μCi/ml for in-plane and 15.3 kcps/μCi/ml for cross-plane. (J.P.N.)

High-resolution disruption halo current measurements using Langmuir probes in Alcator C-Mod

Science.gov (United States)

Tinguely, R. A.; Granetz, R. S.; Berg, A.; Kuang, A. Q.; Brunner, D.; LaBombard, B.

2018-01-01

Halo currents generated during disruptions on Alcator C-Mod have been measured with Langmuir ‘rail’ probes. These rail probes are embedded in a lower outboard divertor module in a closely-spaced vertical (poloidal) array. The dense array provides detailed resolution of the spatial dependence (~1 cm spacing) of the halo current distribution in the plasma scrape-off region with high time resolution (400 kHz digitization rate). As the plasma limits on the outboard divertor plate, the contact point is clearly discernible in the halo current data (as an inversion of current) and moves vertically down the divertor plate on many disruptions. These data are consistent with filament reconstructions of the plasma boundary, from which the edge safety factor of the disrupting plasma can be calculated. Additionally, the halo current ‘footprint’ on the divertor plate is obtained and related to the halo flux width. The voltage driving halo current and the effective resistance of the plasma region through which the halo current flows to reach the probes are also investigated. Estimations of the sheath resistance and halo region resistivity and temperature are given. This information could prove useful for modeling halo current dynamics.

High resolution simultaneous measurements of airborne radionuclides in the pan-Japan sea area

International Nuclear Information System (INIS)

Yamaguchi, Y.; Abe, T.; Murata, Y.M.; Manikandan, N.; Tanaka, K.; Komura, K.

2006-01-01

By the use of ultra low background Ge detectors at Ogoya Underground Laboratory (OUL), it became possible to detect extremely low levels of environmental radionuclides. In this study, we tried to measure high resolution simultaneous measurements of airborne radionuclides at three monitoring points, i.e., 1) Low Level Radioactivity Laboratory (LLRL 40m asl) in Nomi City as the regular monitoring point, 2) Hegura Island Located 50 km from Noto Peninsula in the Sea of Japan to investigate the influence of Asian continent or mainland of Japan, and 3) Shishiku Plateau (640m asl) located about 8 km from LLRL to know vertical difference. Pb-210 and Be-7 were measured nondestructively by ultra low background gamma spectrometry at OUL, Po-210 by alpha spectrometry using Si detectors after the chemical treatment. Various interesting results on the concentrations and variation patterns of airborne radionuclides were obtained, particularly, during drastic meteorological changes such as the passage of typhoon, snow fall and so on. We have been analyzing the influence of the arrival of yellow sand occurred in this spring. (author)

SRS station 16.3: high-resolution applications

CERN Document Server

Murphy, B M; Golshan, M; Moore, M; Reid, J; Kowalski, G

2001-01-01

Station 16.3 is a high-resolution X-ray diffraction beamline at Daresbury Laboratory Synchrotron Radiation Source. The data presented demonstrate the high-resolution available on the station utilising the recently commissioned four-reflection Si 1 1 1 monochromator and three-reflection Si 1 1 1 analyser. For comparison, a reciprocal space map of the two-bounce Si 1 1 1 monochromator and two-bounce analyser is also shown. Operation of the station is illustrated with examples for silicon, and for diamond. Lattice parameter variations were measured with accuracies in the part per million range and lattice tilts at the arc second level (DuMond, Phys. Rev. 52 (1937) 872).

Gold finger formation studied by high-resolution mass spectrometry and in silico methods

NARCIS (Netherlands)

Laskay, Ü.A.; Garino, C.; Tsybin, Y.O.; Salassa, L.; Casini, A.

2015-01-01

High-resolution mass spectrometry and quantum mechanics/molecular mechanics studies were employed for characterizing the formation of two gold finger (GF) domains from the reaction of zinc fingers (ZF) with gold complexes. The influence of both the gold oxidation state and the ZF coordination sphere

High resolution backscattering instruments

International Nuclear Information System (INIS)

Coldea, R.

2001-01-01

The principle of operation of indirect-geometry time-of-flight spectrometers are presented, including the IRIS at the ISIS spallation neutron source. The key features that make those types of spectrometers ideally suited for low-energy spectroscopy are: high energy resolution over a wide dynamic range, and simultaneous measurement over a large momentum transfer range provided by the wide angular detector coverage. To exemplify these features are discussed of single-crystal experiments of the spin dynamics in the two-dimensional frustrated quantum magnet Cs 2 CuCl 4 . (R.P.)

The Ring Counter (RCo): A high resolution IC-Si-CsI(Tl) device for heavy ion reaction studies at 10-30 MeV/A

International Nuclear Information System (INIS)

Moroni, A.; Bruno, M.; Bardelli, L.; Barlini, S.; Brambilla, S.; Casini, G.; Cavaletti, R.; Chiari, M.; Cortesi, A.; D'Agostino, M.; De Sanctis, J.; Geraci, E.; Giordano, G.; Giussani, A.; Gramegna, F.; Guiot, B.; Kravchuk, V.; Lanchais, A.; Margagliotti, G.V.; Nannini, A.; Ordine, A.; Piantelli, S.; Vannini, G.; Vannucci, L.

2006-01-01

An annular detector (Ring Counter, RCo) is presented, which has been designed and built to detect and identify in mass and charge light charged particles and fragments with very low energy thresholds and high energy resolution. It complements the GARFIELD apparatus, operating at INFN Laboratori Nazionali di Legnaro, to detect the forward emitted products of nuclear heavy ion reactions. It consists of eight sectors of a three-stage telescope, each one formed by an ionization chamber followed by eight strips of a silicon detector and by two CsI(Tl) scintillators. Construction features and performances are described and discussed in details

New High-Resolution Absorption Cross-Section Measurements of HCFC-142B in the Mid-Ir

Science.gov (United States)

Le Bris, Karine; Strong, Kimberly; Melo, Stella

2009-06-01

HCFC-142b (1-chloro-1,1-difluoroethane) is a temporary substitute for ozone-depleting chlorofluorocarbons (CFCs). However, due to its high absorption cross-sections in the mid-IR, HCFC-142b is also a highly potent greenhouse gas, now detectable from space by satellite missions. So far, the accuracy of the retrieval has been limited by the lack of reference data in a range of temperatures compatible with atmospheric observations. We present new absorption cross section measurements of HCFC-142b at high-resolution (0.02 cm^{-1}) from 223 K to 283 K in the 600 cm^{-1}- 4000 cm^{-1} spectral window. The composite spectra are calculated for each temperature from a set of acquisitions at different pressures by Fourier transform spectroscopy.

High-resolution 3D dose distribution measured for two low-energy x-ray brachytherapy seeds: 125I and 103Pd

International Nuclear Information System (INIS)

Massillon-JL, G.; Minniti, R.; Mitch, M.G.; Soares, C.G.; Hearn, R.A.

2011-01-01

In this work, we have investigated the 3D absorbed dose distribution around 125 I and 103 Pd low-energy photon brachytherapy seeds using a high-spatial-resolution gel scanning system to address the current difficulty in measuring absorbed dose at close distances to these sources as a consequence of high dose rate gradient. A new version of BANG-gel coupled with a small format laser CT scanner has been used. Measurements were performed with 100 μm resolution in all dimensions. In particular, radial dose function and absorbed dose rate in the plane parallel to the sources longitudinal-axis were derived at radial distances smaller than or equal to 1 cm. In addition, the energy dependence was evaluated, finding that, within measurement uncertainties, the gel response is independent of the energy for energy photon values between 20 keV and 1250 keV. We have observed that at distances larger than 1.4 mm from the source, the delivered dose is similar to predictions from published Monte Carlo calculations (MC) for the 125 I seed. For distances between 1 mm and 3 mm, differences in magnitude and shape are significant for the 103 Pd seed, where an enhancement is observed. In the enhancement region, a difference of up to 70% in the radial dose function was obtained. Such observation suggests a contribution from other radionuclides emitting beta-particles or electrons, and not considered by MC. To understand the effect, spectrometry measurements were performed. A small contribution of 102 Rh/ 102m Rh radionuclide relative to 103 Pd was observed and its importance on the absorbed dose measured at close distances to the seed is time dependent and consequently, avoids reproducible measurements. Finally, the results obtained in this work underscore the importance of using high-spatial-resolution and water-equivalent detectors for measuring absorbed dose in low-energy photon radiation fields.

Resolution-recovery-embedded image reconstruction for a high-resolution animal SPECT system.

Science.gov (United States)

Zeraatkar, Navid; Sajedi, Salar; Farahani, Mohammad Hossein; Arabi, Hossein; Sarkar, Saeed; Ghafarian, Pardis; Rahmim, Arman; Ay, Mohammad Reza

2014-11-01

The small-animal High-Resolution SPECT (HiReSPECT) is a dedicated dual-head gamma camera recently designed and developed in our laboratory for imaging of murine models. Each detector is composed of an array of 1.2 × 1.2 mm(2) (pitch) pixelated CsI(Na) crystals. Two position-sensitive photomultiplier tubes (H8500) are coupled to each head's crystal. In this paper, we report on a resolution-recovery-embedded image reconstruction code applicable to the system and present the experimental results achieved using different phantoms and mouse scans. Collimator-detector response functions (CDRFs) were measured via a pixel-driven method using capillary sources at finite distances from the head within the field of view (FOV). CDRFs were then fitted by independent Gaussian functions. Thereafter, linear interpolations were applied to the standard deviation (σ) values of the fitted Gaussians, yielding a continuous map of CDRF at varying distances from the head. A rotation-based maximum-likelihood expectation maximization (MLEM) method was used for reconstruction. A fast rotation algorithm was developed to rotate the image matrix according to the desired angle by means of pre-generated rotation maps. The experiments demonstrated improved resolution utilizing our resolution-recovery-embedded image reconstruction. While the full-width at half-maximum (FWHM) radial and tangential resolution measurements of the system were over 2 mm in nearly all positions within the FOV without resolution recovery, reaching around 2.5 mm in some locations, they fell below 1.8 mm everywhere within the FOV using the resolution-recovery algorithm. The noise performance of the system was also acceptable; the standard deviation of the average counts per voxel in the reconstructed images was 6.6% and 8.3% without and with resolution recovery, respectively. Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Magnetic properties of iron oxide-based nanoparticles: Study using Mössbauer spectroscopy with a high velocity resolution and magnetization measurements

Energy Technology Data Exchange (ETDEWEB)

Ushakov, M.V. [Institute of Physics and Technology, Ural Federal University, Ekaterinburg 620002 (Russian Federation); Oshtrakh, M.I., E-mail: oshtrakh@gmail.com [Institute of Physics and Technology, Ural Federal University, Ekaterinburg 620002 (Russian Federation); Felner, I. [Racah Institute of Physics, The Hebrew University, Jerusalem (Israel); Semenova, A.S.; Kellerman, D.G. [Institute of Solid State Chemistry, Ural Branch, Russian Academy of Sciences, Ekaterinburg 620990 (Russian Federation); Šepelák, V. [Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Semionkin, V.A. [Institute of Physics and Technology, Ural Federal University, Ekaterinburg 620002 (Russian Federation); Morais, P.C. [School of Chemistry and Chemical Engineering, Anhui University, Hefei 230601 (China); Universidade de Brasília, Instituto de Física, DF, Brasília 70910-900 (Brazil)

2017-06-01

We review the results of the study of magnetite, maghemite and nickel ferrite nanoparticles (NPs), applying for magnetic fluids, using Mössbauer spectroscopy with a high velocity resolution and magnetization measurements. The Mössbauer spectra of these NPs were fitted using a large number of magnetic sextets reflecting NPs complicity. The presence of polar molecules at the magnetite surface in magnetic fluid increases the NPs magnetic moment and the median hyperfine magnetic field. However, surface coating of maghemite NPs with dimeracptosuccinic acid decreases the median hyperfine magnetic field. An example of nickel ferrite NPs demonstrated a new physical model based on distribution of Ni{sup 2+} in the local microenvironment of Fe{sup 3+} which can explain a large number of magnetic sextets in the Mössbauer spectra measured with a high velocity resolution.

Differential cross section measurement of the {sup 12}C(e,e{sup '}pp){sup 10}Be{sub g.s.} reaction

Energy Technology Data Exchange (ETDEWEB)

Makek, M.; Bosnar, D.; Friscic, I. [University of Zagreb, Department of Physics, Faculty of Science, Zagreb (Croatia); Achenbach, P.; Ayerbe Gayoso, C.; Bernauer, J.C.; Boehm, R.; Denig, A.; Distler, M.O.; Merkel, H.; Mueller, U.; Nungesser, L.; Pochodzalla, J.; Sanches Majos, S.; Schlimme, B.S.; Schwamb, M.; Walcher, T. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); Barbieri, C. [University of Surrey, Department of Physics, Guildford (United Kingdom); Giusti, C. [Universita degli Studi di Pavia, Dipartimento di Fisica, Pavia (Italy); INFN, Sezione di Pavia (Italy); Collaboration: A1 Collaboration

2016-09-15

The differential cross section was measured for the {sup 12}C(e,e{sup '}pp){sup 10}Be{sub g.s.} reaction at energy and momentum transfers of 163 MeV and 198 MeV/c, respectively. The measurement was performed at the Mainz Microtron by using two high-resolution magnetic spectrometers of the A1 Collaboration and a newly developed silicon detector telescope. The overall resolution of the detector system was sufficient to distinguish the ground state from the first excited state in {sup 10}Be. We chose a super-parallel geometry that minimizes the effect of two-body currents and emphasizes the effect of nucleon-nucleon correlations. The obtained differential cross section is compared to the theoretical results of the Pavia reaction code in which different processes leading to two-nucleon knockout are accounted for microscopically. The comparison shows a strong sensitivity to nuclear-structure input and the measured cross section is seen to be dominated by the interplay between long- and short-range nucleon-nucleon correlations. Microscopic calculations based on the ab initio self-consistent Green's function method give a reasonable description of the experimental cross section. (orig.)

High-resolution computer-aided moire

Science.gov (United States)

Sciammarella, Cesar A.; Bhat, Gopalakrishna K.

1991-12-01

This paper presents a high resolution computer assisted moire technique for the measurement of displacements and strains at the microscopic level. The detection of micro-displacements using a moire grid and the problem associated with the recovery of displacement field from the sampled values of the grid intensity are discussed. A two dimensional Fourier transform method for the extraction of displacements from the image of the moire grid is outlined. An example of application of the technique to the measurement of strains and stresses in the vicinity of the crack tip in a compact tension specimen is given.

High Angular Resolution Measurements of the Anisotropy of Reflectance of Sea Ice and Snow

Science.gov (United States)

Goyens, C.; Marty, S.; Leymarie, E.; Antoine, D.; Babin, M.; Bélanger, S.

2018-01-01

We introduce a new method to determine the anisotropy of reflectance of sea ice and snow at spatial scales from 1 m2 to 80 m2 using a multispectral circular fish-eye radiance camera (CE600). The CE600 allows measuring radiance simultaneously in all directions of a hemisphere at a 1° angular resolution. The spectral characteristics of the reflectance and its dependency on illumination conditions obtained from the camera are compared to those obtained with a hyperspectral field spectroradiometer manufactured by Analytical Spectral Device, Inc. (ASD). Results confirm the potential of the CE600, with the suggested measurement setup and data processing, to measure commensurable sea ice and snow hemispherical-directional reflectance factor, HDRF, values. Compared to the ASD, the reflectance anisotropy measured with the CE600 provides much higher resolution in terms of directional reflectance (N = 16,020). The hyperangular resolution allows detecting features that were overlooked using the ASD due to its limited number of measurement angles (N = 25). This data set of HDRF further documents variations in the anisotropy of the reflectance of snow and ice with the geometry of observation and illumination conditions and its spectral and spatial scale dependency. Finally, in order to reproduce the hyperangular CE600 reflectance measurements over the entire 400-900 nm spectral range, a regression-based method is proposed to combine the ASD and CE600 measurements. Results confirm that both instruments may be used in synergy to construct a hyperangular and hyperspectral snow and ice reflectance anisotropy data set.

The effect of pattern overlap on the accuracy of high resolution electron backscatter diffraction measurements

Energy Technology Data Exchange (ETDEWEB)

Tong, Vivian, E-mail: v.tong13@imperial.ac.uk [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom); Jiang, Jun [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom); Wilkinson, Angus J. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Britton, T. Ben [Department of Materials, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom)

2015-08-15

High resolution, cross-correlation-based, electron backscatter diffraction (EBSD) measures the variation of elastic strains and lattice rotations from a reference state. Regions near grain boundaries are often of interest but overlap of patterns from the two grains could reduce accuracy of the cross-correlation analysis. To explore this concern, patterns from the interior of two grains have been mixed to simulate the interaction volume crossing a grain boundary so that the effect on the accuracy of the cross correlation results can be tested. It was found that the accuracy of HR-EBSD strain measurements performed in a FEG-SEM on zirconium remains good until the incident beam is less than 18 nm from a grain boundary. A simulated microstructure was used to measure how often pattern overlap occurs at any given EBSD step size, and a simple relation was found linking the probability of overlap with step size. - Highlights: • Pattern overlap occurs at grain boundaries and reduces HR-EBSD accuracy. • A test is devised to measure the accuracy of HR-EBSD in the presence of overlap. • High pass filters can sometimes, but not generally, improve HR-EBSD measurements. • Accuracy of HR-EBSD remains high until the reference pattern intensity is <72%. • 9% of points near a grain boundary will have significant error for 200nm step size in Zircaloy-4.

Development of high-resolution two-dimensional magnetic field measurement system by use of printed-circuit technology

Science.gov (United States)

Akimitsu, Moe; Qinghong, Cao; Sawada, Asuka; Hatano, Hironori; Tanabe, Hiroshi; Ono, Yasushi; TS-Group Team

2017-10-01

We have developed a new-types of high-resolution magnetic probe array for our new magnetic reconnection experiments: TS-3U (ST, FRC: R =0.2m, 2017-) and TS-4U (ST, FRC: R =0.5m, 2018-), using the advanced printed-circuit technology. They are equipped with all three-components of magnetic pick-up coils whose size is 1-5mm x 3mm. Each coil is composed of two-sided coil pattern with line width of 0.05mm. We can install two or three printed arrays in a single glass (ceramic) tube for two or three component measurements. Based on this new probe technique, we started high-resolution and high-accuracy measurement of the current sheet thickness and studied its plasma parameter dependence. We found that the thickness of current sheet increases inversely with the guide toroidal field. It is probably determined by the ion gyroradius in agreement with the particle simulation by Horiuchi etc. While the reconnection speed is steady under low guide field condition, it is observed to oscillate in the specific range of guide field, suggesting transition from the quasi-steady reconnection to the intermittent reconnection. Cause and mechanism for intermittent reconnection will be discussed using the current sheet dissipation and dynamic balance between plasma inflow and outflow. This work supported by JSPS KAKENHI Grant Numbers 15H05750, 15K14279 and 17H04863.

Gamma strength functions and level densities from high-resolution inelastic proton scattering at very forward angles

Science.gov (United States)

Bassauer, Sergej; Neumann-Cosel, Peter von; Tamii, Atsushi

2017-09-01

Inelastic proton scattering at energies of a few 100 MeV and forward angles including 0∘ provides a novel method to measure gamma strength functions (GSF) in nuclei in an energy range of about 5-23 MeV. The experiments provide not only the E1 but also the M1 part of the GSF. The latter is poorly known in heavy nuclei. A case study of 208Pb indicates that the systematics proposed for the M1-GSF in RIPL-3 needs to be substantially revised. Comparison with gamma decay data (e.g. from the Oslo method) allows to test the generalised Brink-Axel (BA) hypothesis in the energy region of the pygmy dipole resonance (PDR) crucial for the modelling of (n,γ) and (γ,n) reactions in astrophysical reaction networks. A fluctuation analysis of the high-resolution data also provides a direct measure of level densities in the energy region well above the neutron threshold, where hardly any experimental information is available.

Magnetic Resonance Super-resolution Imaging Measurement with Dictionary-optimized Sparse Learning

Directory of Open Access Journals (Sweden)

Li Jun-Bao

2017-06-01

Full Text Available Magnetic Resonance Super-resolution Imaging Measurement (MRIM is an effective way of measuring materials. MRIM has wide applications in physics, chemistry, biology, geology, medical and material science, especially in medical diagnosis. It is feasible to improve the resolution of MR imaging through increasing radiation intensity, but the high radiation intensity and the longtime of magnetic field harm the human body. Thus, in the practical applications the resolution of hardware imaging reaches the limitation of resolution. Software-based super-resolution technology is effective to improve the resolution of image. This work proposes a framework of dictionary-optimized sparse learning based MR super-resolution method. The framework is to solve the problem of sample selection for dictionary learning of sparse reconstruction. The textural complexity-based image quality representation is proposed to choose the optimal samples for dictionary learning. Comprehensive experiments show that the dictionary-optimized sparse learning improves the performance of sparse representation.

Atomic-resolution measurements with a new tunable diode laser-based interferometer

DEFF Research Database (Denmark)

Silver, R.M.; Zou, H.; Gonda, S.

2004-01-01

is lightweight and is mounted directly on an ultra-high vacuum scanning tunneling microscope capable of atomic resolution. We report the simultaneous acquisition of an atomic resolution image, while the relative lateral displacement of the tip along the sample distance is measured with the new tunable diode...

Use of high-resolution ultrasound to measure changes in plantar fascia thickness resulting from tissue creep in runners and walkers.

Science.gov (United States)

Welk, Aaron B; Haun, Daniel W; Clark, Thomas B; Kettner, Norman W

2015-01-01

This study sought to use high-resolution ultrasound to measure changes in plantar fascia thickness as a result of tissue creep generated by walking and running. Independent samples of participants were obtained. Thirty-six walkers and 25 runners walked on a treadmill for 10 minutes or ran for 30 minutes, respectively. Standardized measures of the thickness of the plantar fascia were obtained in both groups using high-resolution ultrasound. The mean thickness of the plantar fascia was measured immediately before and after participation. The mean plantar fascia thickness was decreased by 0.06 ± 0.33 mm SD after running and 0.03 ± 0.22 mm SD after walking. The difference between groups was not significant. Although the parameters of this study did not produce significant changes in the plantar fascia thickness, a slightly higher change in the mean thickness of the plantar fascia in the running group deserves further investigation. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

Environmental high resolution electron microscopy and applications to chemical science

OpenAIRE

Boyes, Edward; Gai, Pratibha

2017-01-01

An environmental cell high resolution electron microscope (EHREM) has been developed for in situ studies of dynamic chemical reactions on the atomic scale. It allows access to metastable intermediate phases of catalysts and to sequences of reversible microstructural and chemical development associated with the activation, deactivation and poisoning of a catalyst. Materials transported through air can be restored or recreated and samples damaged, e.g. by dehydration, by the usual vacuum enviro...

Ultra-high resolution protein crystallography

International Nuclear Information System (INIS)

Takeda, Kazuki; Hirano, Yu; Miki, Kunio

2010-01-01

Many protein structures have been determined by X-ray crystallography and deposited with the Protein Data Bank. However, these structures at usual resolution (1.5< d<3.0 A) are insufficient in their precision and quantity for elucidating the molecular mechanism of protein functions directly from structural information. Several studies at ultra-high resolution (d<0.8 A) have been performed with synchrotron radiation in the last decade. The highest resolution of the protein crystals was achieved at 0.54 A resolution for a small protein, crambin. In such high resolution crystals, almost all of hydrogen atoms of proteins and some hydrogen atoms of bound water molecules are experimentally observed. In addition, outer-shell electrons of proteins can be analyzed by the multipole refinement procedure. However, the influence of X-rays should be precisely estimated in order to derive meaningful information from the crystallographic results. In this review, we summarize refinement procedures, current status and perspectives for ultra high resolution protein crystallography. (author)

Activation cross-section measurements of some proton induced reactions on Ni, Co and Mo for proton activation analysis (PAA) purposes

International Nuclear Information System (INIS)

Alharbi, A.A.; Alzahrani, J.; Azzam, A.; Nuclear Research Center, Cairo

2011-01-01

The experimental proton induced reaction cross sections on some elements of the Havar alloy were measured using the activation method and the well established stacked-foil technique combined with high resolution gamma-ray spectroscopy. They included the reactions nat Ni(p,x) 57 Ni, nat Co(p,x) 58(m+g) Co and nat Mo(p,x) 94g,95g,96(m+g) Tc, the aim being to obtain reliable data in the proton energy range up to 26 MeV for some important reactions to be used in the proton activation analysis of steel or other alloys. Irradiations were performed using the CS-30 Cyclotron at KFSH and RC, Riyadh, Saudi Arabia. The activity measurements were carried out in PNU laboratories, Riyadh, Saudi Arabia. The experimental excitation functions for the investigated reactions were constructed and compared with the performed computed theoretical nuclear model calculations using two different codes: ALICE-IPPE and TALYS. A comparison between our measured cross-section values and the available published data is also presented, with a view to checking the consistency of the reported experimental work from various laboratories.

Application of the Oslo method to high resolution gamma spectra

Science.gov (United States)

Simon, A.; Guttormsen, M.; Larsen, A. C.; Beausang, C. W.; Humby, P.

2015-10-01

Hauser-Feshbach statistical model is a widely used tool for calculation of the reaction cross section, in particular for astrophysical processes. The HF model requires as an input an optical potential, gamma-strength function (GSF) and level density (LD) to properly model the statistical properties of the nucleus. The Oslo method is a well established technique to extract GSFs and LDs from experimental data, typically used for gamma-spectra obtained with scintillation detectors. Here, the first application of the Oslo method to high-resolution data obtained using the Ge detectors of the STARLITER setup at TAMU is discussed. The GSFs and LDs extracted from (p,d) and (p,t) reactions on 152154 ,Sm targets will be presented.

High-resolution gamma ray attenuation density measurements on mining exploration drill cores, including cut cores

Science.gov (United States)

Ross, P.-S.; Bourke, A.

2017-01-01

Physical property measurements are increasingly important in mining exploration. For density determinations on rocks, one method applicable on exploration drill cores relies on gamma ray attenuation. This non-destructive method is ideal because each measurement takes only 10 s, making it suitable for high-resolution logging. However calibration has been problematic. In this paper we present new empirical, site-specific correction equations for whole NQ and BQ cores. The corrections force back the gamma densities to the "true" values established by the immersion method. For the NQ core caliber, the density range extends to high values (massive pyrite, 5 g/cm3) and the correction is thought to be very robust. We also present additional empirical correction factors for cut cores which take into account the missing material. These "cut core correction factors", which are not site-specific, were established by making gamma density measurements on truncated aluminum cylinders of various residual thicknesses. Finally we show two examples of application for the Abitibi Greenstone Belt in Canada. The gamma ray attenuation measurement system is part of a multi-sensor core logger which also determines magnetic susceptibility, geochemistry and mineralogy on rock cores, and performs line-scan imaging.

A Decade of High-Resolution Arctic Sea Ice Measurements from Airborne Altimetry

Science.gov (United States)

Duncan, K.; Farrell, S. L.; Connor, L. N.; Jackson, C.; Richter-Menge, J.

2017-12-01

Satellite altimeters carried on board ERS-1,-2, EnviSat, ICESat, CryoSat-2, AltiKa and Sentinel-3 have transformed our ability to map the thickness and volume of the polar sea ice cover, on seasonal and decadal time-scales. The era of polar satellite altimetry has coincided with a rapid decline of the Arctic ice cover, which has thinned, and transitioned from a predominantly multi-year to first-year ice cover. In conjunction with basin-scale satellite altimeter observations, airborne surveys of the Arctic Ocean at the end of winter are now routine. These surveys have been targeted to monitor regions of rapid change, and are designed to obtain the full snow and ice thickness distribution, across a range of ice types. Sensors routinely deployed as part of NASA's Operation IceBridge (OIB) campaigns include the Airborne Topographic Mapper (ATM) laser altimeter, the frequency-modulated continuous-wave snow radar, and the Digital Mapping System (DMS). Airborne measurements yield high-resolution data products and thus present a unique opportunity to assess the quality and characteristics of the satellite observations. We present a suite of sea ice data products that describe the snow depth and thickness of the Arctic ice cover during the last decade. Fields were derived from OIB measurements collected between 2009-2017, and from reprocessed data collected during ad-hoc sea ice campaigns prior to OIB. Our bespoke algorithms are designed to accommodate the heterogeneous sea ice surface topography, that varies at short spatial scales. We assess regional and inter-annual variability in the sea ice thickness distribution. Results are compared to satellite-derived ice thickness fields to highlight the sensitivities of satellite footprints to the tails of the thickness distribution. We also show changes in the dynamic forcing shaping the ice pack over the last eight years through an analysis of pressure-ridge sail-height distributions and surface roughness conditions

SU-E-I-40: New Method for Measurement of Task-Specific, High-Resolution Detector System Performance

Energy Technology Data Exchange (ETDEWEB)

Loughran, B; Singh, V; Jain, A; Bednarek, D; Rudin, S [University at Buffalo, Buffalo, NY (United States)

2014-06-01

Purpose: Although generalized linear system analytic metrics such as GMTF and GDQE can evaluate performance of the whole imaging system including detector, scatter and focal-spot, a simplified task-specific measured metric may help to better compare detector systems. Methods: Low quantum-noise images of a neuro-vascular stent with a modified ANSI head phantom were obtained from the average of many exposures taken with the high-resolution Micro-Angiographic Fluoroscope (MAF) and with a Flat Panel Detector (FPD). The square of the Fourier Transform of each averaged image, equivalent to the measured product of the system GMTF and the object function in spatial-frequency space, was then divided by the normalized noise power spectra (NNPS) for each respective system to obtain a task-specific generalized signal-to-noise ratio. A generalized measured relative object detectability (GM-ROD) was obtained by taking the ratio of the integral of the resulting expressions for each detector system to give an overall metric that enables a realistic systems comparison for the given detection task. Results: The GM-ROD provides comparison of relative performance of detector systems from actual measurements of the object function as imaged by those detector systems. This metric includes noise correlations and spatial frequencies relevant to the specific object. Additionally, the integration bounds for the GM-ROD can be selected to emphasis the higher frequency band of each detector if high-resolution image details are to be evaluated. Examples of this new metric are discussed with a comparison of the MAF to the FPD for neuro-vascular interventional imaging. Conclusion: The GM-ROD is a new direct-measured task-specific metric that can provide clinically relevant comparison of the relative performance of imaging systems. Supported by NIH Grant: 2R01EB002873 and an equipment grant from Toshiba Medical Systems Corporation.

High-resolution investigations of edge effects in neutron imaging

International Nuclear Information System (INIS)

Strobl, M.; Kardjilov, N.; Hilger, A.; Kuehne, G.; Frei, G.; Manke, I.

2009-01-01

Edge enhancement is the main effect measured by the so-called inline or propagation-based neutron phase contrast imaging method. The effect has originally been explained by diffraction, and high spatial coherence has been claimed to be a necessary precondition. However, edge enhancement has also been found in conventional imaging with high resolution. In such cases the effects can produce artefacts and hinder quantification. In this letter the edge effects at cylindrical shaped samples and long straight edges have been studied in detail. The enhancement can be explained by refraction and total reflection. Using high-resolution imaging, where spatial resolutions better than 50 μm could be achieved, refraction and total reflection peaks - similar to diffraction patterns - could be separated and distinguished.

Airborne High Spectral Resolution Lidar Aerosol Measurements during MILAGRO and TEXAQS/GOMACCS

Science.gov (United States)

Ferrare, Richard; Hostetler, Chris; Hair, John; Cook Anthony; Harper, David; Burton, Sharon; Clayton, Marian; Clarke, Antony; Russell, Phil; Redemann, Jens

2007-01-01

Two1 field experiments conducted during 2006 provided opportunities to investigate the variability of aerosol properties near cities and the impacts of these aerosols on air quality and radiative transfer. The Megacity Initiative: Local and Global Research Observations (MILAGRO) /Megacity Aerosol Experiment in Mexico City (MAX-MEX)/Intercontinental Chemical Transport Experiment-B (INTEX-B) joint experiment conducted during March 2006 investigated the evolution and transport of pollution from Mexico City. The Texas Air Quality Study (TEXAQS)/Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS) (http://www.al.noaa.gov/2006/) conducted during August and September 2006 investigated climate and air quality in the Houston/Gulf of Mexico region. During both missions, the new NASA Langley airborne High Spectral Resolution Lidar (HSRL) was deployed on the NASA Langley B200 King Air aircraft and measured profiles of aerosol extinction, backscattering, and depolarization to: 1) characterize the spatial and vertical distributions of aerosols, 2) quantify aerosol extinction and optical thickness contributed by various aerosol types, 3) investigate aerosol variability near clouds, 4) evaluate model simulations of aerosol transport, and 5) assess aerosol optical properties derived from a combination of surface, airborne, and satellite measurements.

Low-resolution gamma-ray measurements of uranium enrichment

International Nuclear Information System (INIS)

Sprinkle, J.K. Jr.; Christiansen, A.; Cole, R.; Collins, M.L.

1996-01-01

Facilities that process special nuclear material perform periodic inventories. In bulk facilities that process low-enriched uranium, these inventories and their audits are based primarily on weight and enrichment measurements. Enrichment measurements determine the 211 U weight fraction of the uranium compound from the passive gamma-ray emissions of the sample. Both international inspectors and facility operators rely on the capability to make in-field gamma-ray measurements of uranium enrichment. These users require rapid, portable measurement capability. Some in-field measurements have been biased, forcing the inspectors to resort to high-resolution measurements or mass spectrometry to accomplish their goals

Recent applications of gas chromatography with high-resolution mass spectrometry.

Science.gov (United States)

Špánik, Ivan; Machyňáková, Andrea

2018-01-01

Gas chromatography coupled to high-resolution mass spectrometry is a powerful analytical method that combines excellent separation power of gas chromatography with improved identification based on an accurate mass measurement. These features designate gas chromatography with high-resolution mass spectrometry as the first choice for identification and structure elucidation of unknown volatile and semi-volatile organic compounds. Gas chromatography with high-resolution mass spectrometry quantitative analyses was previously focused on the determination of dioxins and related compounds using magnetic sector type analyzers, a standing requirement of many international standards. The introduction of a quadrupole high-resolution time-of-flight mass analyzer broadened interest in this method and novel applications were developed, especially for multi-target screening purposes. This review is focused on the development and the most interesting applications of gas chromatography coupled to high-resolution mass spectrometry towards analysis of environmental matrices, biological fluids, and food safety since 2010. The main attention is paid to various approaches and applications of gas chromatography coupled to high-resolution mass spectrometry for non-target screening to identify contaminants and to characterize the chemical composition of environmental, food, and biological samples. The most interesting quantitative applications, where a significant contribution of gas chromatography with high-resolution mass spectrometry over the currently used methods is expected, will be discussed as well. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High spatiotemporal resolution measurement of regional lung air volumes from 2D phase contrast x-ray images.

Science.gov (United States)

Leong, Andrew F T; Fouras, Andreas; Islam, M Sirajul; Wallace, Megan J; Hooper, Stuart B; Kitchen, Marcus J

2013-04-01

Described herein is a new technique for measuring regional lung air volumes from two-dimensional propagation-based phase contrast x-ray (PBI) images at very high spatial and temporal resolution. Phase contrast dramatically increases lung visibility and the outlined volumetric reconstruction technique quantifies dynamic changes in respiratory function. These methods can be used for assessing pulmonary disease and injury and for optimizing mechanical ventilation techniques for preterm infants using animal models. The volumetric reconstruction combines the algorithms of temporal subtraction and single image phase retrieval (SIPR) to isolate the image of the lungs from the thoracic cage in order to measure regional lung air volumes. The SIPR algorithm was used to recover the change in projected thickness of the lungs on a pixel-by-pixel basis (pixel dimensions ≈ 16.2 μm). The technique has been validated using numerical simulation and compared results of measuring regional lung air volumes with and without the use of temporal subtraction for removing the thoracic cage. To test this approach, a series of PBI images of newborn rabbit pups mechanically ventilated at different frequencies was employed. Regional lung air volumes measured from PBI images of newborn rabbit pups showed on average an improvement of at least 20% in 16% of pixels within the lungs in comparison to that measured without the use of temporal subtraction. The majority of pixels that showed an improvement was found to be in regions occupied by bone. Applying the volumetric technique to sequences of PBI images of newborn rabbit pups, it is shown that lung aeration at birth can be highly heterogeneous. This paper presents an image segmentation technique based on temporal subtraction that has successfully been used to isolate the lungs from PBI chest images, allowing the change in lung air volume to be measured over regions as small as the pixel size. Using this technique, it is possible to measure

High resolution solar observations

International Nuclear Information System (INIS)

Title, A.

1985-01-01

Currently there is a world-wide effort to develop optical technology required for large diffraction limited telescopes that must operate with high optical fluxes. These developments can be used to significantly improve high resolution solar telescopes both on the ground and in space. When looking at the problem of high resolution observations it is essential to keep in mind that a diffraction limited telescope is an interferometer. Even a 30 cm aperture telescope, which is small for high resolution observations, is a big interferometer. Meter class and above diffraction limited telescopes can be expected to be very unforgiving of inattention to details. Unfortunately, even when an earth based telescope has perfect optics there are still problems with the quality of its optical path. The optical path includes not only the interior of the telescope, but also the immediate interface between the telescope and the atmosphere, and finally the atmosphere itself

Marker-referred movement measurement with grey-scale coordinate extraction for high-resolution real-time 3D at 100 Hz

NARCIS (Netherlands)

Furnée, E.H.; Jobbá, A.; Sabel, J.C.; Veenendaal, H.L.J. van; Martin, F.; Andriessen, D.C.W.G.

1997-01-01

A review of early history in photography highlights the origin of cinefilm as a scientific tool for image-based measurement of human and animal motion. The paper is concerned with scanned-area video sensors (CCD) and a computer interface for the real-time, high-resolution extraction of image

Grain rotation and lattice deformation during photoinduced chemical reactions revealed by in situ X-ray nanodiffraction.

Science.gov (United States)

Huang, Zhifeng; Bartels, Matthias; Xu, Rui; Osterhoff, Markus; Kalbfleisch, Sebastian; Sprung, Michael; Suzuki, Akihiro; Takahashi, Yukio; Blanton, Thomas N; Salditt, Tim; Miao, Jianwei

2015-07-01

In situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) have been used to investigate many physical science phenomena, ranging from phase transitions, chemical reactions and crystal growth to grain boundary dynamics. A major limitation of in situ XRD and TEM is a compromise that has to be made between spatial and temporal resolution. Here, we report the development of in situ X-ray nanodiffraction to measure high-resolution diffraction patterns from single grains with up to 5 ms temporal resolution. We observed, for the first time, grain rotation and lattice deformation in chemical reactions induced by X-ray photons: Br(-) + hv → Br + e(-) and e(-) + Ag(+) → Ag(0). The grain rotation and lattice deformation associated with the chemical reactions were quantified to be as fast as 3.25 rad s(-1) and as large as 0.5 Å, respectively. The ability to measure high-resolution diffraction patterns from individual grains with a temporal resolution of several milliseconds is expected to find broad applications in materials science, physics, chemistry and nanoscience.

A Numerical Method to Generate High Temporal Resolution Precipitation Time Series by Combining Weather Radar Measurements with a Nowcast Model

DEFF Research Database (Denmark)

Nielsen, Jesper Ellerbæk; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

2014-01-01

The topic of this paper is temporal interpolation of precipitation observed by weather radars. Precipitation measurements with high spatial and temporal resolution are, in general, desired for urban drainage applications. An advection-based interpolation method is developed which uses methods...

An angle encoder for super-high resolution and super-high accuracy using SelfA

Science.gov (United States)

Watanabe, Tsukasa; Kon, Masahito; Nabeshima, Nobuo; Taniguchi, Kayoko

2014-06-01

Angular measurement technology at high resolution for applications such as in hard disk drive manufacturing machines, precision measurement equipment and aspherical process machines requires a rotary encoder with high accuracy, high resolution and high response speed. However, a rotary encoder has angular deviation factors during operation due to scale error or installation error. It has been assumed to be impossible to achieve accuracy below 0.1″ in angular measurement or control after the installation onto the rotating axis. Self-calibration (Lu and Trumper 2007 CIRP Ann. 56 499; Kim et al 2011 Proc. MacroScale; Probst 2008 Meas. Sci. Technol. 19 015101; Probst et al Meas. Sci. Technol. 9 1059; Tadashi and Makoto 1993 J. Robot. Mechatronics 5 448; Ralf et al 2006 Meas. Sci. Technol. 17 2811) and cross-calibration (Probst et al 1998 Meas. Sci. Technol. 9 1059; Just et al 2009 Precis. Eng. 33 530; Burnashev 2013 Quantum Electron. 43 130) technologies for a rotary encoder have been actively discussed on the basis of the principle of circular closure. This discussion prompted the development of rotary tables which achieve reliable and high accuracy angular verification. We apply these technologies for the development of a rotary encoder not only to meet the requirement of super-high accuracy but also to meet that of super-high resolution. This paper presents the development of an encoder with 221 = 2097 152 resolutions per rotation (360°), that is, corresponding to a 0.62″ signal period, achieved by the combination of a laser rotary encoder supplied by Magnescale Co., Ltd and a self-calibratable encoder (SelfA) supplied by The National Institute of Advanced Industrial Science & Technology (AIST). In addition, this paper introduces the development of a rotary encoder to guarantee ±0.03″ accuracy at any point of the interpolated signal, with respect to the encoder at the minimum resolution of 233, that is, corresponding to a 0.0015″ signal period after

Process-independent radiative-correction formula for single-tag and double-tag measurements of γγ reactions

International Nuclear Information System (INIS)

Ong, S.; Kessler, P.

1988-01-01

A simple and process-independent formula is given for radiative corrections in single-tag and double-tag measurements of γγ reactions. Its conditions of validity are that (i) in the γγ process itself all particles produced are detected and (ii) final-state particles, including the tagged electron(s), are measured with a good resolution in energy and momentum

A high resolution x-ray fluorescence spectrometer for near edge absorption studies

International Nuclear Information System (INIS)

Stojanoff, V.; Hamalainen, K.; Siddons, D.P.; Hastings, J.B.; Berman, L.E.; Cramer, S.; Smith, G.

1991-01-01

A high resolution fluorescence spectrometer using a Johann geometry in a back scattering arrangement was developed. The spectrometer, with a resolution of 0.3 eV at 6.5 keV, combined with an incident beam, with a resolution of 0.7 eV, form the basis of a high resolution instrument for measuring x-ray absorption spectra. The advantages of the instrument are illustrated with the near edge absorption spectrum of dysprosium nitrate. 10 refs., 4 figs

High resolution study of high mass pairs and high transverse momentum particles

International Nuclear Information System (INIS)

Smith, S.R.

1983-01-01

Preliminary experiments involving the high resolution spectrometer (experiment 605) at Fermilab are described. The spectrometer is designed for the study of pairs of particles at large invariant masses and single particles at large transverse momenta. A number of applications of the apparatus in the study of Drell-Yan processes, e.g. transverse momentum measurement, are discussed

Diagnostic technique for measuring fusion reaction rate for inertial confinement fusion experiments at Shen Guang-III prototype laser facility

International Nuclear Information System (INIS)

Wang Feng; Peng Xiao-Shi; Liu Shen-Ye; Xu Tao; Kang Dong-Guo

2013-01-01

A study is conducted using a two-dimensional simulation program (Lared-s) with the goal of developing a technique to evaluate the effect of Rayleigh-Taylor growth in a neutron fusion reaction region. Two peaks of fusion reaction rate are simulated by using a two-dimensional simulation program (Lared-s) and confirmed by the experimental results. A neutron temporal diagnostic (NTD) system is developed with a high temporal resolution of ∼ 30 ps at the Shen Guang-III (SG-III) prototype laser facility in China, to measure the fusion reaction rate history. With the shape of neutron reaction rate curve and the spherical harmonic function in this paper, the degree of Rayleigh-Taylor growth and the main source of the neutron yield in our experiment can be estimated qualitatively. This technique, including the diagnostic system and the simulation program, may provide important information for obtaining a higher neutron yield in implosion experiments of inertial confinement fusion

Measurement needs guided by synthetic radar scans in high-resolution model output

Science.gov (United States)

Varble, A.; Nesbitt, S. W.; Borque, P.

2017-12-01

Microphysical and dynamical process interactions within deep convective clouds are not well understood, partly because measurement strategies often focus on statistics of cloud state rather than cloud processes. While processes cannot be directly measured, they can be inferred with sufficiently frequent and detailed scanning radar measurements focused on the life cycleof individual cloud regions. This is a primary goal of the 2018-19 DOE ARM Cloud, Aerosol, and Complex Terrain Interactions (CACTI) and NSF Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaigns in central Argentina, where orographic deep convective initiation is frequent with some high-impact systems growing into the tallest and largest in the world. An array of fixed and mobile scanning multi-wavelength dual-polarization radars will be coupled with surface observations, sounding systems, multi-wavelength vertical profilers, and aircraft in situ measurements to characterize convective cloud life cycles and their relationship with environmental conditions. While detailed cloud processes are an observational target, the radar scan patterns that are most ideal for observing them are unclear. They depend on the locations and scales of key microphysical and dynamical processes operating within the cloud. High-resolution simulations of clouds, while imperfect, can provide information on these locations and scales that guide radar measurement needs. Radar locations are set in the model domain based on planned experiment locations, and simulatedorographic deep convective initiation and upscale growth are sampled using a number of different scans involving RHIs or PPIs with predefined elevation and azimuthal angles that approximately conform with radar range and beam width specifications. Each full scan pattern is applied to output atsingle model time steps with time step intervals that depend on the length of time

High-resolution measurement of the unsteady velocity field to evaluate blood damage induced by a mechanical heart valve.

Science.gov (United States)

Bellofiore, Alessandro; Quinlan, Nathan J

2011-09-01

We investigate the potential of prosthetic heart valves to generate abnormal flow and stress patterns, which can contribute to platelet activation and lysis according to blood damage accumulation mechanisms. High-resolution velocity measurements of the unsteady flow field, obtained with a standard particle image velocimetry system and a scaled-up model valve, are used to estimate the shear stresses arising downstream of the valve, accounting for flow features at scales less than one order of magnitude larger than blood cells. Velocity data at effective spatial and temporal resolution of 60 μm and 1.75 kHz, respectively, enabled accurate extraction of Lagrangian trajectories and loading histories experienced by blood cells. Non-physiological stresses up to 10 Pa were detected, while the development of vortex flow in the wake of the valve was observed to significantly increase the exposure time, favouring platelet activation. The loading histories, combined with empirical models for blood damage, reveal that platelet activation and lysis are promoted at different stages of the heart cycle. Shear stress and blood damage estimates are shown to be sensitive to measurement resolution.

Synthesis and electroplating of high resolution insulated carbon nanotube scanning probes for imaging in liquid solutions.

Science.gov (United States)

Roberts, N A; Noh, J H; Lassiter, M G; Guo, S; Kalinin, S V; Rack, P D

2012-04-13

High resolution and isolated scanning probe microscopy (SPM) is in demand for continued development of energy storage and conversion systems involving chemical reactions at the nanoscale as well as an improved understanding of biological systems. Carbon nanotubes (CNTs) have large aspect ratios and, if leveraged properly, can be used to develop high resolution SPM probes. Isolation of SPM probes can be achieved by depositing a dielectric film and selectively etching at the apex of the probe. In this paper the fabrication of a high resolution and isolated SPM tip is demonstrated using electron beam induced etching of a dielectric film deposited onto an SPM tip with an attached CNT at the apex.

High-resolution bent-crystal spectrometer for the ultra-soft x-ray region

International Nuclear Information System (INIS)

Beiersdorfer, P.; von Goeler, S.; Bitter, M.; Hill, K.W.; Hulse, R.A.; Walling, R.S.

1988-10-01

A multichannel vacuum Brag-crystal spectrometer has been developed for high-resolution measurements of the line emission from tokamak plasmas in the wavelength region between 4 and 25 /angstrom/. The spectrometer employs a bent crystal in Johann geometry and a microchannel-plate intensified photodiode array. The instrument is capable of measuring high-resolution spectra (λ/Δλ ∼ 3000) with fast time resolution (4 msec per spectrum) and good spatial resolution (3 cm). The spectral bandwidth is Δλ/λ 0 = 8/angstrom/. A simple tilt mechanism allows access to different wavelength intervals. In order to illustrate the utility of the new spectrometer, time- and space-resolved measurements of the n = 3 to n = 2 spectrum of selenium from the Princeton Large Torus tokamak plasmas are presented. The data are used to determine the plasma transport parameters and to infer the radial distribution of fluorinelike, neonlike, and sodiumlike ions of selenium in the plasma. The new ultra-soft x-ray spectrometer has thus enabled us to demonstrate the utility of high-resolution L-shell spectroscopy of neonlike ions as a fusion diagnostic. 43 refs., 23 figs

Hyper-resolution urban flood modeling using high-resolution radar precipitation and LiDAR data

Science.gov (United States)

Noh, S. J.; Lee, S.; Lee, J.; Seo, D. J.

2016-12-01

Floods occur most frequently among all natural hazards, often causing widespread economic damage and loss of human lives. In particular, urban flooding is becoming increasingly costly and difficult to manage with a greater concentration of population and assets in urban centers. Despite of known benefits for accurate representation of small scale features and flow interaction among different flow domains, which have significant impact on flood propagation, high-resolution modeling has not been fully utilized due to expensive computation and various uncertainties from model structure, input and parameters. In this study, we assess the potential of hyper-resolution hydrologic-hydraulic modeling using high-resolution radar precipitation and LiDAR data for improved urban flood prediction and hazard mapping. We describe a hyper-resolution 1D-2D coupled urban flood model for pipe and surface flows and evaluate the accuracy of the street-level inundation information produced. For detailed geometric representation of urban areas and for computational efficiency, we use 1 m-resolution topographical data, processed from LiDAR measurements, in conjunction with adaptive mesh refinement. For street-level simulation in large urban areas at grid sizes of 1 to 10 m, a hybrid parallel computing scheme using MPI and openMP is also implemented in a high-performance computing system. The modeling approach developed is applied for the Johnson Creek Catchment ( 40 km2), which makes up the Arlington Urban Hydroinformatics Testbed. In addition, discussion will be given on availability of hyper-resolution simulation archive for improved real-time flood mapping.

A highly versatile automatized setup for quantitative measurements of PHIP enhancements

Science.gov (United States)

Kiryutin, Alexey S.; Sauer, Grit; Hadjiali, Sara; Yurkovskaya, Alexandra V.; Breitzke, Hergen; Buntkowsky, Gerd

2017-12-01

The design and application of a versatile and inexpensive experimental extension to NMR spectrometers is described that allows to carry out highly reproducible PHIP experiments directly in the NMR sample tube, i.e. under PASADENA condition, followed by the detection of the NMR spectra of hyperpolarized products with high spectral resolution. Employing this high resolution it is feasible to study kinetic processes in the solution with high accuracy. As a practical example the dissolution of hydrogen gas in the liquid and the PHIP kinetics during the hydrogenation reaction of Fmoc-O-propargyl-L-tyrosine in acetone-d6 are monitored. The timing of the setup is fully controlled by the pulse-programmer of the NMR spectrometer. By flushing with an inert gas it is possible to efficiently quench the hydrogenation reaction in a controlled fashion and to detect the relaxation of hyperpolarization without a background reaction. The proposed design makes it possible to carry out PHIP experiments in an automatic mode and reliably determine the enhancement of polarized signals.

High-Resolution State-Selected Ion-Molecule Reaction Studies Using Pulsed Field Ionization Photoelectron-Secondary Ion Coincidence Method

National Research Council Canada - National Science Library

Qian, X

2003-01-01

We have developed an octopole-quadrupole photoionization apparatus at the Advanced Light Source for absolute integral cross-section measurements of rovibrational-state-selected ion-molecule reactions...

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors

DEFF Research Database (Denmark)

Andersen, Thomas; Jensen, Robert; Christensen, M. K.

2012-01-01

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal...

High-resolution coded-aperture design for compressive X-ray tomography using low resolution detectors

Science.gov (United States)

Mojica, Edson; Pertuz, Said; Arguello, Henry

2017-12-01

One of the main challenges in Computed Tomography (CT) is obtaining accurate reconstructions of the imaged object while keeping a low radiation dose in the acquisition process. In order to solve this problem, several researchers have proposed the use of compressed sensing for reducing the amount of measurements required to perform CT. This paper tackles the problem of designing high-resolution coded apertures for compressed sensing computed tomography. In contrast to previous approaches, we aim at designing apertures to be used with low-resolution detectors in order to achieve super-resolution. The proposed method iteratively improves random coded apertures using a gradient descent algorithm subject to constraints in the coherence and homogeneity of the compressive sensing matrix induced by the coded aperture. Experiments with different test sets show consistent results for different transmittances, number of shots and super-resolution factors.

High resolution eddy current microscopy

Science.gov (United States)

Lantz, M. A.; Jarvis, S. P.; Tokumoto, H.

2001-01-01

We describe a sensitive scanning force microscope based technique for measuring local variations in resistivity by monitoring changes in the eddy current induced damping of a cantilever with a magnetic tip oscillating above a conducting sample. To achieve a high sensitivity, we used a cantilever with an FeNdBLa particle mounted on the tip. Resistivity measurements are demonstrated on a silicon test structure with a staircase doping profile. Regions with resistivities of 0.0013, 0.0041, and 0.022 Ω cm are clearly resolved with a lateral resolution of approximately 180 nm. For this range of resistivities, the eddy current induced damping is found to depend linearly on the sample resistivity.

Dynamic Raman imaging system with high spatial and temporal resolution

Science.gov (United States)

Wang, Lei; Dai, Yinzhen; He, Hao; Lv, Ruiqi; Zong, Cheng; Ren, Bin

2017-09-01

There is an increasing need to study dynamic changing systems with significantly high spatial and temporal resolutions. In this work, we integrated point-scanning, line-scanning, and wide-field Raman imaging techniques into a single system. By using an Electron Multiplying CCD (EMCCD) with a high gain and high frame rate, we significantly reduced the time required for wide-field imaging, making it possible to monitor the electrochemical reactions in situ. The highest frame rate of EMCDD was ˜50 fps, and the Raman images for a specific Raman peak can be obtained by passing the signal from the sample through the Liquid Crystal Tunable Filter. The spatial resolutions of scanning imaging and wide-field imaging with a 100× objective (NA = 0.9) are 0.5 × 0.5 μm2 and 0.36 × 0.36 μm2, respectively. The system was used to study the surface plasmon resonance of Au nanorods, the surface-enhanced Raman scattering signal distribution for Au Nanoparticle aggregates, and dynamic Raman imaging of an electrochemical reacting system.

Auroral radar measurements at 16-cm wavelength with high range and time resolution

International Nuclear Information System (INIS)

Schlegel, K.; Turunen, T.; Moorcroft, D.R.

1990-01-01

Auroral radar measurements performed with the EISCAT facility are presented. Backscatter cross sections of the irregularities produced by the two-stream (Farley-Buneman) or gradient drift plasma instabilities have been recorded with a range separation of 1.5 km, corresponding to a spacing of successive values in height of about 0.4 km. The apparent height profiles of the backscatter have a width of about 5-6 km and occur between 95 and 112 km altitude, with a mean at 104 km. Very often, fast motions of the backscatter layers are observed which can be explained as fast moving ionospheric structures controlled by magnetospheric convection. The maximal time resolution of the measurements is 12.5 ms. The statistics of the backscatter amplitudes at this time resolution is close to a Rice distribution with a Rice parameter a ∼ 3.7. The observed backscatter spectra do not change significantly in shape when the integration time is reduced from 5 s to 100 ms

Tumour size measurement in a mouse model using high resolution MRI

International Nuclear Information System (INIS)

Montelius, Mikael; Ljungberg, Maria; Horn, Michael; Forssell-Aronsson, Eva

2012-01-01

Animal models are frequently used to assess new treatment methods in cancer research. MRI offers a non-invasive in vivo monitoring of tumour tissue and thus allows longitudinal measurements of treatment effects, without the need for large cohorts of animals. Tumour size is an important biomarker of the disease development, but to our knowledge, MRI based size measurements have not yet been verified for small tumours (10 −2 –10 −1 g). The aim of this study was to assess the accuracy of MRI based tumour size measurements of small tumours on mice. 2D and 3D T2-weighted RARE images of tumour bearing mice were acquired in vivo using a 7 T dedicated animal MR system. For the 3D images the acquired image resolution was varied. The images were exported to a PC workstation where the tumour mass was determined assuming a density of 1 g/cm 3 , using an in-house developed tool for segmentation and delineation. The resulting data were compared to the weight of the resected tumours after sacrifice of the animal using regression analysis. Strong correlations were demonstrated between MRI- and necropsy determined masses. In general, 3D acquisition was not a prerequisite for high accuracy. However, it was slightly more accurate than 2D when small (<0.2 g) tumours were assessed for inter- and intraobserver variation. In 3D images, the voxel sizes could be increased from 160 3 μm 3 to 240 3 μm 3 without affecting the results significantly, thus reducing acquisition time substantially. 2D MRI was sufficient for accurate tumour size measurement, except for small tumours (<0.2 g) where 3D acquisition was necessary to reduce interobserver variation. Acquisition times between 15 and 50 minutes, depending on tumour size, were sufficient for accurate tumour volume measurement. Hence, it is possible to include further MR investigations of the tumour, such as tissue perfusion, diffusion or metabolic composition in the same MR session

Shuttle high resolution accelerometer package experiment results - Atmospheric density measurements between 60-160 km

Science.gov (United States)

Blanchard, R. C.; Hinson, E. W.; Nicholson, J. Y.

1988-01-01

Indirect or inferred values of atmospheric density encountered by the Shuttle Orbiter during reentry have been calculated from acceleration measurements made by the High Resolution Accelerometer Package (HiRAP) and the Orbiter Inertial Measurement Unit (IMU) liner accelerometers. The atmospheric density data developed from this study represent a significant gain with respect to the body of data collected to date by various techniques in the altitude range of 60 to 160 km. The data are unique in that they cover a very wide horizontal range during each flight and provide insight into the actual density variations encountered along the reentry flight path. The data, which were collected over about 3 years, are also characterized by variations in solar activity, geomagnetic index, and local solar time. Comparison of the flight-derived densities with various atmospheric models have been made, and analyses have attempted to characterize the data and to show correlation with selected physical variables.

Day and Night Variability of CO2 Fluxes and Priming Effects under zea Mays Measured in High Resolution

Science.gov (United States)

Splettstoesser, Thomas; Pausch, Johanna

2017-04-01

Plant induced increase of soil organic matter turnover rates contribute to carbon emissions in agricultural land use systems. In order to better understand these rhizosphere priming effects, we conducted an experiment which enabled us to monitor CO2 fluxes under Zea mays plants in high resolution. The experiment was conducted in a climate chamber where the plants were grown in tightly sealed boxes for 40 days and CO2 efflux from soil was measured twice a day. Continuous 13C-CO2 label was used to allow differentiation between plant- and soil-derived CO2.This enabled us to monitor root respiration and soil organic matter turnover in the early stages of plant growth and to highlight changes in soil CO2 emissions and priming effects between day and night. The measurements were conducted with a PICARRO G2131-I C high-precision isotopic CO2 Analyzer (PICARRO INC.) utilizing an automated valve system governed by a CR1000 data logger (Campbell Scientific). After harvest roots and shoots were analyzed for 13C content. Microbial biomass, root length density and enzymatic activities in soil were measured and linked to soil organic matter turnover rates. Results show an increased soil CO2 efflux at day time periods and an overall increase with increasing plant biomass. No difference in chloroform fumigation extractable microbial biomass has been found but a strong negative priming effect was measured in the short experimental period, suggesting that the microbes shifted to the utilization of plant exudates without actual microbial growth triggered by the new labile C input. This is coherent with the observed shift in enzyme kinetics. With this experimental setup we show that measurement of priming effects in high resolution can be achieved.

High temporal resolution in situ measurement of the effective particle size characteristics of fluvial suspended sediment.

Science.gov (United States)

Williams, N D; Walling, D E; Leeks, G J L

2007-03-01

This paper reports the use of a LISST-100 device to monitor the effective particle size characteristics of suspended sediment in situ, and at a quasi-continuous temporal resolution. The study site was located on the River Exe at Thorverton, Devon, UK. This device has not previously been utilized in studies of fluvial suspended sediment at the storm event scale, and existing studies of suspended sediment dynamics have not involved such a high temporal resolution for extended periods. An evaluation of the field performance of the instrument is presented, with respect to innovative data collection and analysis techniques. It was found that trends in the effective particle size distribution (EPSD) and degree of flocculation of suspended sediment at the study site were highly complex, and showed significant short-term variability that has not previously been documented in the fluvial environment. The collection of detailed records of EPSD facilitated interpretation of the dynamic evolution of the size characteristics of suspended sediment, in relation to its likely source and delivery and flocculation mechanisms. The influence of measurement frequency is considered in terms of its implications for future studies of the particle size of fluvial suspended sediment employing in situ data acquisition.

High spatial and spectral resolution measurements of Jupiter's auroral regions using Gemini-North-TEXES

Science.gov (United States)

Sinclair, J. A.; Orton, G. S.; Greathouse, T. K.; Lacy, J.; Giles, R.; Fletcher, L. N.; Vogt, M.; Irwin, P. G.

2017-12-01

Jupiter exhibits auroral emission at a multitude of wavelengths. Auroral emission at X-ray, ultraviolet and near-infrared wavelengths demonstrate the precipitation of ion and electrons in Jupiter's upper atmosphere, at altitudes exceeding 250 km above the 1-bar level. Enhanced mid-infrared emission of CH4, C2H2, C2H4 and further hydrocarbons is also observed coincident with Jupiter's auroral regions. Retrieval analyses of infrared spectra from IRTF-TEXES (Texas Echelon Cross Echelle Spectrograph on NASA's Infrared Telescope Facility) indicate strong heating at the 1-mbar level and evidence of ion-neutral chemistry, which enriches the abundances of unsaturated hydrocarbons (Sinclair et al., 2017b, doi:10.1002/2017GL073529, Sinclair et al., 2017c (under review)). The extent to which these phenomena in the stratosphere are correlated and coupled physically with the shorter-wavelength auroral emission originating from higher altitudes has been a challenge due to the limited spatial resolution available on the IRTF. Smaller-scale features observed in the near-infrared and ultraviolet emission, such as the main `oval', transient `swirls' and dusk-active regions within the main oval (e.g. Stallard et al., 2014, doi:10.1016/j/Icarus.2015.12.044, Nichols et al., 2017, doi: 10.1002/2017GL073029) are potentially being blurred in the mid-infrared by the diffraction-limited resolution (0.7") of IRTF's 3-metre primary aperture. However, on March 17-19th 2017, we obtained spectral measurements of H2 S(1), CH4, C2H2, C2H4 and C2H6 emission of Jupiter's high latitudes using TEXES on Gemini-North, which has a 8-metre primary aperture. This rare opportunity combines the superior spectral resolving power of TEXES and the high spatial resolution provided by Gemini-North's 8-metre aperture. We will perform a retrieval analyses to determine the 3D distributions of temperature, C2H2, C2H4 and C2H6. The morphology will be compared with near-contemporaneous measurements of H3+ emission from

High resolution computed tomography of positron emitters

International Nuclear Information System (INIS)

Derenzo, S.E.; Budinger, T.F.; Cahoon, J.L.; Huesman, R.H.; Jackson, H.G.

1976-10-01

High resolution computed transaxial radionuclide tomography has been performed on phantoms containing positron-emitting isotopes. The imaging system consisted of two opposing groups of eight NaI(Tl) crystals 8 mm x 30 mm x 50 mm deep and the phantoms were rotated to measure coincident events along 8960 projection integrals as they would be measured by a 280-crystal ring system now under construction. The spatial resolution in the reconstructed images is 7.5 mm FWHM at the center of the ring and approximately 11 mm FWHM at a radius of 10 cm. We present measurements of imaging and background rates under various operating conditions. Based on these measurements, the full 280-crystal system will image 10,000 events per sec with 400 μCi in a section 1 cm thick and 20 cm in diameter. We show that 1.5 million events are sufficient to reliably image 3.5-mm hot spots with 14-mm center-to-center spacing and isolated 9-mm diameter cold spots in phantoms 15 to 20 cm in diameter

Urban Boundary Extraction and Urban Sprawl Measurement Using High-Resolution Remote Sensing Images: a Case Study of China's Provincial

Science.gov (United States)

Wang, H.; Ning, X.; Zhang, H.; Liu, Y.; Yu, F.

2018-04-01

Urban boundary is an important indicator for urban sprawl analysis. However, methods of urban boundary extraction were inconsistent, and construction land or urban impervious surfaces was usually used to represent urban areas with coarse-resolution images, resulting in lower precision and incomparable urban boundary products. To solve above problems, a semi-automatic method of urban boundary extraction was proposed by using high-resolution image and geographic information data. Urban landscape and form characteristics, geographical knowledge were combined to generate a series of standardized rules for urban boundary extraction. Urban boundaries of China's 31 provincial capitals in year 2000, 2005, 2010 and 2015 were extracted with above-mentioned method. Compared with other two open urban boundary products, accuracy of urban boundary in this study was the highest. Urban boundary, together with other thematic data, were integrated to measure and analyse urban sprawl. Results showed that China's provincial capitals had undergone a rapid urbanization from year 2000 to 2015, with the area change from 6520 square kilometres to 12398 square kilometres. Urban area of provincial capital had a remarkable region difference and a high degree of concentration. Urban land became more intensive in general. Urban sprawl rate showed inharmonious with population growth rate. About sixty percent of the new urban areas came from cultivated land. The paper provided a consistent method of urban boundary extraction and urban sprawl measurement using high-resolution remote sensing images. The result of urban sprawl of China's provincial capital provided valuable urbanization information for government and public.

High-resolution continuous flow analysis setup for water isotopic measurement from ice cores using laser spectroscopy

Science.gov (United States)

Emanuelsson, B. D.; Baisden, W. T.; Bertler, N. A. N.; Keller, E. D.; Gkinis, V.

2014-12-01

2013 Roosevelt Island Climate Evolution (RICE) ice core processing campaign achieved high precision measurements, in particular for δD, with high temporal resolution for the upper part of the core, where a seasonally resolved isotopic signal is preserved.

Validation of meter-scale surface faulting offset measurements from high-resolution topographic data

Science.gov (United States)

Salisbury, Barrett; Haddad, D.E.; Rockwell, T.K.; Arrowsmith, R.; Madugo, C.; Zielke, O.; Scharer, Katherine M.

2015-01-01

Studies of active fault zones have flourished with the availability of high-resolution topographic data, particularly where airborne light detection and ranging (lidar) and structure from motion (SfM) data sets provide a means to remotely analyze submeter-scale fault geomorphology. To determine surface offset at a point along a strike-slip earthquake rupture, geomorphic features (e.g., stream channels) are measured days to centuries after the event. Analysis of these and cumulatively offset features produces offset distributions for successive earthquakes that are used to understand earthquake rupture behavior. As researchers expand studies to more varied terrain types, climates, and vegetation regimes, there is an increasing need to standardize and uniformly validate measurements of tectonically displaced geomorphic features. A recently compiled catalog of nearly 5000 earthquake offsets across a range of measurement and reporting styles provides insight into quality rating and uncertainty trends from which we formulate best-practice and reporting recommendations for remote studies. In addition, a series of public and beginner-level studies validate the remote methodology for a number of tools and emphasize considerations to enhance measurement accuracy and precision for beginners and professionals. Our investigation revealed that (1) standardizing remote measurement methods and reporting quality rating schemes is essential for the utility and repeatability of fault-offset measurements; (2) measurement discrepancies often involve misinterpretation of the offset geomorphic feature and are a function of the investigator’s experience; (3) comparison of measurements made by a single investigator in different climatic regions reveals systematic differences in measurement uncertainties attributable to variation in feature preservation; (4) measuring more components of a displaced geomorphic landform produces more consistently repeatable estimates of offset; and (5

Validation of meter-scale surface faulting offset measurements from high-resolution topographic data

KAUST Repository

Salisbury, J. Barrett

2015-10-24

Studies of active fault zones have flourished with the availability of high-resolution topographic data, particularly where airborne light detection and ranging (lidar) and structure from motion (SfM) data sets provide a means to remotely analyze submeter- scale fault geomorphology. To determine surface offset at a point along a strike-slip earthquake rupture, geomorphic features (e.g., stream channels) are measured days to centuries after the event. Analysis of these and cumulatively offset features produces offset distributions for successive earthquakes that are used to understand earthquake rupture behavior. As researchers expand studies to more varied terrain types, climates, and vegetation regimes, there is an increasing need to standardize and uniformly validate measurements of tectonically displaced geomorphic features. A recently compiled catalog of nearly 5000 earthquake offsets across a range of measurement and reporting styles provides insight into quality rating and uncertainty trends from which we formulate best-practice and reporting recommendations for remote studies. In addition, a series of public and beginner-level studies validate the remote methodology for a number of tools and emphasize considerations to enhance measurement accuracy and precision for beginners and professionals. Our investigation revealed that (1) standardizing remote measurement methods and reporting quality rating schemes is essential for the utility and repeatability of fault-offset measurements; (2) measurement discrepancies often involve misinterpretation of the offset geomorphic feature and are a function of the investigator\\'s experience; (3) comparison of measurements made by a single investigator in different climatic regions reveals systematic differences in measurement uncertainties attributable to variation in feature preservation; (4) measuring more components of a displaced geomorphic landform produces more consistently repeatable estimates of offset; and (5

Study of highly excited high spin states via the (HI, α) reaction

International Nuclear Information System (INIS)

Kubono, S.

1982-01-01

Three subjects are discussed in this paper. 1) The mechanism of (HI, α) reactions is briefly studied. 2) Possible excitation of molecular resonance states of 12 C- 12 C in 24 Mg through the 12 C( 16 O, α) 24 Mg reaction were investigated. A precise measurement of the level widths in 24 Mg did not support the previous report that the molecular states seen in 12 C + 12 C scattering had been excited in the transfer reaction 12 C( 16 O, α) 24 Mg. 3) Highly excited states in 28 Si, which have a large parentage of 12 C- 16 O, were also studied via the 12 C( 20 Ne, α) 28 Si reaction. An angular correlation measurement revealed the lowest 8 + and 10 + states at 14.00 and 15.97 MeV, respectively, which were selectively excited in the 12 C( 20 Ne, α) reaction. These results suggest a possible new band in 28 Si. (author)

Gamma strength functions and level densities from high-resolution inelastic proton scattering at very forward angles

Directory of Open Access Journals (Sweden)

Bassauer Sergej

2017-01-01

Full Text Available Inelastic proton scattering at energies of a few 100 MeV and forward angles including 0∘ provides a novel method to measure gamma strength functions (GSF in nuclei in an energy range of about 5–23 MeV. The experiments provide not only the E1 but also the M1 part of the GSF. The latter is poorly known in heavy nuclei. A case study of 208Pb indicates that the systematics proposed for the M1-GSF in RIPL-3 needs to be substantially revised. Comparison with gamma decay data (e.g. from the Oslo method allows to test the generalised Brink-Axel (BA hypothesis in the energy region of the pygmy dipole resonance (PDR crucial for the modelling of (n,γ and (γ,n reactions in astrophysical reaction networks. A fluctuation analysis of the high-resolution data also provides a direct measure of level densities in the energy region well above the neutron threshold, where hardly any experimental information is available.

Berkeley High-Resolution Ball

International Nuclear Information System (INIS)

Diamond, R.M.

1984-10-01

Criteria for a high-resolution γ-ray system are discussed. Desirable properties are high resolution, good response function, and moderate solid angle so as to achieve not only double- but triple-coincidences with good statistics. The Berkeley High-Resolution Ball involved the first use of bismuth germanate (BGO) for anti-Compton shield for Ge detectors. The resulting compact shield permitted rather close packing of 21 detectors around a target. In addition, a small central BGO ball gives the total γ-ray energy and multiplicity, as well as the angular pattern of the γ rays. The 21-detector array is nearly complete, and the central ball has been designed, but not yet constructed. First results taken with 9 detector modules are shown for the nucleus 156 Er. The complex decay scheme indicates a transition from collective rotation (prolate shape) to single- particle states (possibly oblate) near spin 30 h, and has other interesting features

A Study of Correlations among Image Resolution, Reaction Time, and Extent of Motion in Remote Motor Interactions

Directory of Open Access Journals (Sweden)

Zoltán Rusák

2014-01-01

Full Text Available Motor interaction in virtual sculpting, dance trainings, and physiological rehabilitation requires close virtual proximity of users, which may be hindered by low resolution of images and system latency. This paper reports on the results of our investigation aiming to explore the pros and cons of using ultrahigh 4K resolution displays (4096 × 2160 pixels in remote motor interaction. 4K displays are able to overcome the problem of visible pixels and they are able to show more accurate image details on the level of textures, shadows, and reflections. It was our assumption that such image details can not only satisfy visual comfort of the users, but also provide detailed visual cues and improve the reaction time of users in motor interaction. To validate this hypothesis, we explored the relationships between the reaction time of subjects responding to a series of action-reaction type of games and resolution of the image used in an experiment. The results of our experiment showed that the subjects’ reaction time is significantly shorter in 4K images than in HD or VGA images in motor interaction with small motion envelope.

Eddy covariance measurements with high-resolution time-of-flight aerosol mass spectrometry: a new approach to chemically resolved aerosol fluxes

Directory of Open Access Journals (Sweden)

D. K. Farmer

2011-06-01

Full Text Available Although laboratory studies show that biogenic volatile organic compounds (VOCs yield substantial secondary organic aerosol (SOA, production of biogenic SOA as indicated by upward fluxes has not been conclusively observed over forests. Further, while aerosols are known to deposit to surfaces, few techniques exist to provide chemically-resolved particle deposition fluxes. To better constrain aerosol sources and sinks, we have developed a new technique to directly measure fluxes of chemically-resolved submicron aerosols using the high-resolution time-of-flight aerosol mass spectrometer (HR-AMS in a new, fast eddy covariance mode. This approach takes advantage of the instrument's ability to quantitatively identify both organic and inorganic components, including ammonium, sulphate and nitrate, at a temporal resolution of several Hz. The new approach has been successfully deployed over a temperate ponderosa pine plantation in California during the BEARPEX-2007 campaign, providing both total and chemically resolved non-refractory (NR PM₁ fluxes. Average deposition velocities for total NR-PM₁ aerosol at noon were 2.05 ± 0.04 mm s⁻¹. Using a high resolution measurement of the NH₂⁺ and NH₃⁺ fragments, we demonstrate the first eddy covariance flux measurements of particulate ammonium, which show a noon-time deposition velocity of 1.9 ± 0.7 mm s⁻¹ and are dominated by deposition of ammonium sulphate.

An angle encoder for super-high resolution and super-high accuracy using SelfA

International Nuclear Information System (INIS)

Watanabe, Tsukasa; Kon, Masahito; Nabeshima, Nobuo; Taniguchi, Kayoko

2014-01-01

Angular measurement technology at high resolution for applications such as in hard disk drive manufacturing machines, precision measurement equipment and aspherical process machines requires a rotary encoder with high accuracy, high resolution and high response speed. However, a rotary encoder has angular deviation factors during operation due to scale error or installation error. It has been assumed to be impossible to achieve accuracy below 0.1″ in angular measurement or control after the installation onto the rotating axis. Self-calibration (Lu and Trumper 2007 CIRP Ann. 56 499; Kim et al 2011 Proc. MacroScale; Probst 2008 Meas. Sci. Technol. 19 015101; Probst et al Meas. Sci. Technol. 9 1059; Tadashi and Makoto 1993 J. Robot. Mechatronics 5 448; Ralf et al 2006 Meas. Sci. Technol. 17 2811) and cross-calibration (Probst et al 1998 Meas. Sci. Technol. 9 1059; Just et al 2009 Precis. Eng. 33 530; Burnashev 2013 Quantum Electron. 43 130) technologies for a rotary encoder have been actively discussed on the basis of the principle of circular closure. This discussion prompted the development of rotary tables which achieve reliable and high accuracy angular verification. We apply these technologies for the development of a rotary encoder not only to meet the requirement of super-high accuracy but also to meet that of super-high resolution. This paper presents the development of an encoder with 2 21 = 2097 152 resolutions per rotation (360°), that is, corresponding to a 0.62″ signal period, achieved by the combination of a laser rotary encoder supplied by Magnescale Co., Ltd and a self-calibratable encoder (SelfA) supplied by The National Institute of Advanced Industrial Science and Technology (AIST). In addition, this paper introduces the development of a rotary encoder to guarantee ±0.03″ accuracy at any point of the interpolated signal, with respect to the encoder at the minimum resolution of 2 33 , that is, corresponding to a 0.0015″ signal period

High-resolution spectroscopy of gases for industrial applications

OpenAIRE

Fateev, Alexander; Clausen, Sønnik

2012-01-01

High-resolution spectroscopy of gases is a powerful technique which has various fundamental and practical applications: in situ simultaneous measurements of gas temperature and gas composition, radiative transfer modeling, validation of existing and developing of new databases and etc. Existing databases (e.g. HITRAN, HITEMP or CDSD) can normally be used for absorption spectra calculations at limited temperature/pressure ranges. Therefore experimental measurements of absorption/transmission s...

High-Resolution Experimental Investigation of mass transfer enhancement by chemical oxidation from DNAPL entrapped in variable-aperture fractures

Science.gov (United States)

Arshadi, M.; Rajaram, H.; Detwiler, R. L.; Jones, T.

2012-12-01

Permanganate oxidation of DNAPL- contaminated fractured rock is an effective remediation technology. Permanganate ion reacts with dissolved DNAPL in a bi-molecular oxidation-reduction reaction. The consumption of dissolved DNAPL in this reaction results in increased concentration gradients away from the free-phase DNAPL, resulting in reaction-enhanced mass transfer, which accelerates contaminant removal. The specific objective of our research was to perform high-resolution non-intrusive experimental studies of permanganate oxidation in a 15.24 × 15.24 cm, transparent, analog, variable-aperture fracture with complex initial TCE entrapped phase geometry. Our experimental system uses light-transmission techniques to accurately measure both fracture aperture and the evolution of individual entrapped DNAPL blobs during the remediation experiments at high resolution (pixel size : 6.2×10-3 cm). Three experiments were performed with different flow rates and permanganate inflow concentrations to observe DNAPL-permanganate interactions across a broader range of conditions. Prior to initiating each experiment, the aperture field within the fracture was measured. The oxidation experiment was initiated by TCE injection into the water saturated fracture till the TCE reached the outflow end, followed by water re-injection through the fracture. The flowing water mobilized some TCE. We continued injection of water till TCE mobilization ceased, leaving behind the residual TCE entrapped within the variable-aperture fracture. Subsequently, permanganate injection through the fracture resulted in propagation of a fingered reaction front into the fracture. We developed image processing algorithms to analyze the evolution of DNAPL phase geometry over the duration of the experiment. The permanganate consumption rate varied significantly within the fracture due to the complex flow and DNAPL concentration fields. Precipitated MnO2 was clearly evident on the downstream side of DNAPL blobs

Reaction-time-resolved measurements of laser-induced fluorescence in a shock tube with a single laser pulse

Science.gov (United States)

Zabeti, S.; Fikri, M.; Schulz, C.

2017-11-01

Shock tubes allow for the study of ultra-fast gas-phase reactions on the microsecond time scale. Because the repetition rate of the experiments is low, it is crucial to gain as much information as possible from each individual measurement. While reaction-time-resolved species concentration and temperature measurements with fast absorption methods are established, conventional laser-induced fluorescence (LIF) measurements with pulsed lasers provide data only at a single reaction time. Therefore, fluorescence methods have rarely been used in shock-tube diagnostics. In this paper, a novel experimental concept is presented that allows reaction-time-resolved LIF measurements with one single laser pulse using a test section that is equipped with several optical ports. After the passage of the shock wave, the reactive mixture is excited along the center of the tube with a 266-nm laser beam directed through a window in the end wall of the shock tube. The emitted LIF signal is collected through elongated sidewall windows and focused onto the entrance slit of an imaging spectrometer coupled to an intensified CCD camera. The one-dimensional spatial resolution of the measurement translates into a reaction-time-resolved measurement while the species information can be gained from the spectral axis of the detected two-dimensional image. Anisole pyrolysis was selected as the benchmark reaction to demonstrate the new apparatus.

High-resolution measurement, line identification, and spectral modeling of the Kβ spectrum of heliumlike argon emitted by a laser-produced plasma using a gas-puff target

International Nuclear Information System (INIS)

Skobelev, I.Y.; Faenov, A.Y.; Dyakin, V.M.; Fiedorowicz, H.; Bartnik, A.; Szczurek, M.; Beiersdorfer, P.; Nilsen, J.; Osterheld, A.L.

1997-01-01

We present an analysis of the spectrum of satellite transitions to the He-β line in ArXVII. High-resolution measurements of the spectra from laser-heated Ar-gas-puff targets are made with spectral resolution of 10000 and spatial resolution of better than 50 μm. These are compared with tokamak measurements. Several different lines are identified in the spectra and the spectral analysis is used to determine the plasma parameters in the gas-puff laser-produced plasma. The data complement those from tokamak measurements to provide more complete information on the satellite spectra. copyright 1997 The American Physical Society

Measurement of isotopic cross sections of the fission fragments produced in 500 AMeV 208Pb + p reaction

International Nuclear Information System (INIS)

Fernandez-Dominguez, B.

2003-03-01

The aim of this work is the study of the fission fragments produced in the spallation reaction 208 Pb + p at 500 AMeV. The fission fragments from Z=23 up to Z=59 have been detected and identified by using the inverse kinematics technique with the high-resolution spectrometer FRS. The production cross sections and the recoil velocities of 430 nuclei have been measured. The measured data have been compared with previous data. The isotopic distributions show a high precision. However, the absolute value of the fission cross section is higher than expected. From the experimental data the characteristics of the average fissioning system have been reconstructed (Z fis , A fis , E* fis ). In addition, the number of post-fission neutrons emitted from the fission fragments, v post , has been determined by using a new method. The experimental data have been compared to the two-steps models describing the spallation reaction. The impact of the model parameters on the observables has been analysed and the reasons Leading to the observed differences between the codes are also presented. This analyse shows a good agreement with the INCL4+ABLA code. (author)

Analysis of twenty five impurities in uranium matrix by ICP-MS with iron measurement optimized by using reaction collision cell, cold plasma or medium resolution

International Nuclear Information System (INIS)

Quemet, Alexandre; Brennetot, Rene; Chevalier, Emilie; Prian, Edwina; Laridon, Anne-Laure; Fichet, Pascal; Goutelard, Florence; Mariet, Clarisse; Laszak, Ivan

2012-01-01

An analytical procedure was developed to determine the concentration of 25 impurities (Li, Be, Ti, V. Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, Ag, Cd, In, Sm, Eu, Gd, Dy, W, Pb, Bi and Th) in a uranium matrix using the quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). The dissolution of U 3 O 8 powder was made with a mixture of hydrochloric acid and nitric acid. Then, a selective separation of uranium using the UTEVA column was used before measurement by Q-ICP-MS. The procedure developed was verified using the Certified Reference Material 'Morille'. The analytical results agree well except for 5 elements where values are underestimated (Li, Be, In, Pb and Bi). Among the list of impurities, iron was particularly investigated because it is well known that this element possesses a polyatomic interference that increases the detection limit. A comparison between iron detection limits obtained with different methods was performed. Iron polyatomic interference was at least reduced, or at best entirely resolved in some cases, by using the cold plasma or the collision/reaction cell with several gases (He, NH 3 and CH 4 ). High-resolution ICP-MS was used to compare the results obtained. A detection limit as low as 8 ng L -1 was achieved. (authors)

Ambulatory Measurement of Ground Reaction Forces

NARCIS (Netherlands)

Veltink, Peter H.; Liedtke, Christian; Droog, Ed

2004-01-01

The measurement of ground reaction forces is important in the biomechanical analysis of gait and other motor activities. It is the purpose of this study to show the feasibility of ambulatory measurement of ground reaction forces using two six degrees of freedom sensors mounted under the shoe. One

Development of a high-resolution cavity-beam position monitor

Directory of Open Access Journals (Sweden)

Yoichi Inoue

2008-06-01

Full Text Available We have developed a high-resolution cavity-beam position monitor (BPM to be used at the focal point of the ATF2, which is a test beam line that is now being built to demonstrate stable orbit control at ∼nanometer resolution. The design of the cavity structure was optimized for the Accelerator Test Facility (ATF beam in various ways. For example, the cavity has a rectangular shape in order to isolate two dipole modes in orthogonal directions, and a relatively thin gap that is less sensitive to trajectory inclination. A two stage homodyne mixer with highly sensitive electronics and phase-sensitive detection was also developed. Two BPM blocks, each containing two cavity BPMs, were installed in the existing ATF beam line using a rigid support frame. After testing the basic characteristics, we measured the resolution using three BPMs. The system demonstrated 8.7 nm position resolution over a dynamic range of 5  μm.

Development of a high-resolution cavity-beam position monitor

Science.gov (United States)

Inoue, Yoichi; Hayano, Hitoshi; Honda, Yosuke; Takatomi, Toshikazu; Tauchi, Toshiaki; Urakawa, Junji; Komamiya, Sachio; Nakamura, Tomoya; Sanuki, Tomoyuki; Kim, Eun-San; Shin, Seung-Hwan; Vogel, Vladimir

2008-06-01

We have developed a high-resolution cavity-beam position monitor (BPM) to be used at the focal point of the ATF2, which is a test beam line that is now being built to demonstrate stable orbit control at ˜nanometer resolution. The design of the cavity structure was optimized for the Accelerator Test Facility (ATF) beam in various ways. For example, the cavity has a rectangular shape in order to isolate two dipole modes in orthogonal directions, and a relatively thin gap that is less sensitive to trajectory inclination. A two stage homodyne mixer with highly sensitive electronics and phase-sensitive detection was also developed. Two BPM blocks, each containing two cavity BPMs, were installed in the existing ATF beam line using a rigid support frame. After testing the basic characteristics, we measured the resolution using three BPMs. The system demonstrated 8.7 nm position resolution over a dynamic range of 5μm.

High-resolution photocurrent microscopy using near-field cathodoluminescence of quantum dots

Directory of Open Access Journals (Sweden)

Heayoung P. Yoon

2013-06-01

Full Text Available We report a fast, versatile photocurrent imaging technique to visualize the local photo response of solar energy devices and optoelectronics using near-field cathodoluminescence (CL from a homogeneous quantum dot layer. This approach is quantitatively compared with direct measurements of high-resolution Electron Beam Induced Current (EBIC using a thin film solar cell (n-CdS / p-CdTe. Qualitatively, the observed image contrast is similar, showing strong enhancement of the carrier collection efficiency at the p-n junction and near the grain boundaries. The spatial resolution of the new technique, termed Q-EBIC (EBIC using quantum dots, is determined by the absorption depth of photons. The results demonstrate a new method for high-resolution, sub-wavelength photocurrent imaging measurement relevant for a wide range of applications.

High-Resolution Gamma-Ray Imaging Measurements Using Externally Segmented Germanium Detectors

Science.gov (United States)

Callas, J.; Mahoney, W.; Skelton, R.; Varnell, L.; Wheaton, W.

1994-01-01

Fully two-dimensional gamma-ray imaging with simultaneous high-resolution spectroscopy has been demonstrated using an externally segmented germanium sensor. The system employs a single high-purity coaxial detector with its outer electrode segmented into 5 distinct charge collection regions and a lead coded aperture with a uniformly redundant array (URA) pattern. A series of one-dimensional responses was collected around 511 keV while the system was rotated in steps through 180 degrees. A non-negative, linear least-squares algorithm was then employed to reconstruct a 2-dimensional image. Corrections for multiple scattering in the detector, and the finite distance of source and detector are made in the reconstruction process.

High Time Resolution Astrophysics

CERN Document Server

Phelan, Don; Shearer, Andrew

2008-01-01

High Time Resolution Astrophysics (HTRA) is an important new window to the universe and a vital tool in understanding a range of phenomena from diverse objects and radiative processes. This importance is demonstrated in this volume with the description of a number of topics in astrophysics, including quantum optics, cataclysmic variables, pulsars, X-ray binaries and stellar pulsations to name a few. Underlining this science foundation, technological developments in both instrumentation and detectors are described. These instruments and detectors combined cover a wide range of timescales and can measure fluxes, spectra and polarisation. These advances make it possible for HTRA to make a big contribution to our understanding of the Universe in the next decade.

Measurements of atmospheric mercury with high time resolution: recent applications in environmental research and monitoring.

Science.gov (United States)

Ebinghaus, R; Kock, H H; Schmolke, S R

2001-11-01

In the past five years automated high time-resolution measurements of mercury species in ambient air have promoted remarkable progress in the understanding of the spatial distribution, short-term variability, and fate of this priority pollutant in the lower troposphere. Examples show the wide range of possible applications of these techniques in environmental research and monitoring. Presented applications of measurement methods for total gaseous mercury (TGM) include long-term monitoring of atmospheric mercury at a coastal station, simultaneous measurements during a south-to-north transect measurement campaign covering a distance of approximately 800 km, the operation on board of a research aircraft, and the quantification of mercury emissions from naturally enriched surface soils. First results obtained with a new method for the determination of reactive gaseous mercury (RGM) are presented. Typical background concentrations of TGM are between 1.5 and 2 ng m(-3) in the lower troposphere. Concentrations of RGM have been determined at a rural site in Germany between 2 and 35 pg m(-3). Flux measurements over naturally enriched surface soils in the Western U.S.A. have revealed emission fluxes of up to 200 ng Hg m(-1) h(-1) under dry conditions.

High-Resolution PET Detector. Final report

International Nuclear Information System (INIS)

Karp, Joel

2014-01-01

The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface

Elementary reaction rate measurements at high temperatures by tunable-laser flash-absorption

Energy Technology Data Exchange (ETDEWEB)

Hessler, J.P. [Argonne National Laboratory, IL (United States)

1993-12-01

The major objective of this program is to measure thermal rate coefficients and branching ratios of elementary reactions. To perform these measurements, the authors constructed an ultrahigh-purity shock tube to generate temperatures between 1000 and 5500 K. The tunable-laser flash-absorption technique is used to measure the rate of change of the concentration of species which absorb below 50,000 cm{sup {minus}1} e.g.: OH, CH, and CH{sub 3}. This technique is being extended into the vacuum-ultraviolet spectral region where one can measure atomic species e.g.: H, D, C, O, and N; and diatomic species e.g.: O{sub 2}, CO, and OH.

Time resolution performance studies of contemporary high speed photomultipliers

International Nuclear Information System (INIS)

Leskovar, B.; Lo, C.C.

1978-01-01

The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single phtoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed high speed photomultipliers. Descriptions are given of both the measuring techniques and the measuring systems. 16 refs

High spin states excited by the (p, t) reaction on lead isotopes

Energy Technology Data Exchange (ETDEWEB)

Kumabe, I.; Hyakutake, M. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering; Yuasa, K.; Yamagata, T.; Kishimoto, S.; Ikegami, H.; Muraoka, M [eds.

1980-01-01

In order to find high spin states the sup(204, 206, 208)Pb (p, t) reactions have been investigated with RCNP isochronous cyclotron and a high resolution magnetic spectrograph ''RAIDEN''. The experimental angular distributions were analyzed by DWBA calculations, and the lowest 10/sup +/, 12/sup +/ (i sub(13/2))/sup 2/ and 11/sup -/ (i sub(13/2), h sub(9/2)) states in /sup 202/Pb, /sup 204/Pb and /sup 206/Pb were established.

High-Resolution 3 T MR Microscopy Imaging of Arterial Walls

International Nuclear Information System (INIS)

Sailer, Johannes; Rand, Thomas; Berg, Andreas; Sulzbacher, Irene; Peloschek, P.; Hoelzenbein, Thomas; Lammer, Johannes

2006-01-01

Purpose. To achieve a high spatial resolution in MR imaging that allows for clear visualization of anatomy and even histology and documentation of plaque morphology in in vitro samples from patients with advanced atherosclerosis. A further objective of our study was to evaluate whether T2-weighted high-resolution MR imaging can provide accurate classification of atherosclerotic plaque according to a modified American Heart Association classification. Methods. T2-weighted images of arteries were obtained in 13 in vitro specimens using a 3 T MR unit (Medspec 300 Avance/Bruker, Ettlingen, Germany) combined with a dedicated MR microscopy system. Measurement parameters were: T2-weighted sequences with TR 3.5 sec, TE 15-120 msec; field of view (FOV) 1.4 x 1.4; NEX 8; matrix 192; and slice thickness 600 μm. MR measurements were compared with corresponding histologic sections. Results. We achieved excellent spatial and contrast resolution in all specimens. We found high agreement between MR images and histology with regard to the morphology and extent of intimal proliferations in all but 2 specimens. We could differentiate fibrous caps and calcifications from lipid plaque components based on differences in signal intensity in order to differentiate hard and soft atheromatous plaques. Hard plaques with predominantly intimal calcifications were found in 7 specimens, and soft plaques with a cholesterol/lipid content in 5 cases. In all specimens, hemorrhage or thrombus formation, and fibrotic and hyalinized tissue could be detected on both MR imaging and histopathology. Conclusion. High-resolution, high-field MR imaging of arterial walls demonstrates the morphologic features, volume, and extent of intimal proliferations with high spatial and contrast resolution in in vitro specimens and can differentiate hard and soft plaques

A high resolution detector for H0 → γγ

International Nuclear Information System (INIS)

Atiya, M.S.; Kycia, T.F.

1991-01-01

SSC detectors represent a challenging departure, both in size and precision, from currently operating detectors. In this note we enumerate some of the benefits of using high magnetic fields both to simplify the detector and improve its resolution and sensitivity. We have chosen an arrangement optimized to search for the reaction H 0 → γγ. The arrangement also has the excellent momentum resolution for muons and electrons considered critical for the discovery of such processes as H 0 → Z 0 Z 0 → ell + ell - ell + ell - , H 0 → Z 0 Z 0 → ell + ell - ell + ell - , new and narrow vector bosons, and bound states of extra generational quarks. This detection scheme represents an improvement in the H 0 → γγ mass resolution of at least a factor of 7 beyond the best currently proposed detectors. In addition, we have a significantly improved rejection of common H 0 → γγ backgrounds. As indeed most experiments do not exceed their initial projections, this extra factor could insure the unambiguous discovery of this decay should it indeed occur. As no reasonably realistic detector can achieve excellent detection for all physics signatures we chose to give tip on excellent hadron calorimetry. For Higgs masses between 80 and 150 GeV/c 2 the Higgs decay into two photons is an excellent signature. To date, all attempts to search for this decay mode have centered on the use of electromagnetic calorimetry. We are proposing a different approach. We will convert the two photons close to the production point and measure the momenta of the electron pairs

Contribution to the understanding of ion-gas reactions in ICP-MS collision reaction cells: application to the resolution of isobaric and polyatomic interferences

International Nuclear Information System (INIS)

Quemet, A.

2012-01-01

Inductively Coupled Plasma Mass Spectrometry (ICP-MS) emerged as the most essential technique in inorganic analytical chemistry thanks to its numerous assets, particularly its flexibility, its sensitivity and its reproducibility. As part of the elementary and isotopic analysis of irradiated fuel and transmutation target, the analyst is faced with a complex mass spectrum, due to the presence of many radionuclides. ICP-MS can not differentiate ions with the same mass, which induces isobaric and polyatomic interferences when the ions at the same mass are different chemical species. Last generations of ICP-MS have introduced collision reaction cells. It can in situ reduce these isobaric or polyatomic interferences. The cell is a multipole (quadrupole, hexapole or octupole) device filled with a collision and/or reaction gas. The gas molecules collide or possibly react with the ion beam, which eliminates or reduces interferences. Such resolution of interferences is based on the difference of chemical behaviours between the analyte and the interfering species: the choice of the gas is crucial. A better understanding of the 'ion - gas' reaction should help choosing the reacting gases. Three ICP-MS, with the different cell geometries, were used for this study: Perkin Elmer Elan DRC e (quadrupole), Thermo Fischer X serie II (hexapole) and Agilent Technologies 7700x (octupole). The effects of the cell geometry on different experimental parameters and on the resolution of the 56 Fe + / 40 Ar 16 O + polyatomic interferences were examined to measure iron at trace or ultra-trace level. This preliminary study was applied to measure iron as impurities in uranium oxide, the method was then validated with a Certified Reference Material. The reactivities of transition metals (Zr, Ru, Pd, Ag, Cd, Sn), lanthanides (La, Ce, Nd, Sm, Eu, Gd, Dy, Er and Yb) and actinides (U, Np, Pu, Am and Cm), elements of interest in the nuclear field, are studied with numerous gases (O 2 , CO, CO 2 , N 2

High resolution inelastic gamma-ray measurements with a white neutron source from 1 to 200 MeV

Energy Technology Data Exchange (ETDEWEB)

Nelson, R.O.; Laymon, C.M.; Wender, S.A.

1990-01-01

Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n,{alpha}), (n,n{alpha}), (n,p), (n,np), (n,nnp) and (n,xn) for 1 {le} {times} {le} 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation function measurements and greatly extends the energy range for such data. The results of these measurements will provide a database for interpretation of gamma-ray spectra from the planned Mars Observer mission, aid in radiation transport calculations, allow verification of nuclear reaction models, and improve the evaluated neutron reaction data base.

High resolution inelastic gamma-ray measurements with a white neutron source from 1 to 200 MeV

International Nuclear Information System (INIS)

Nelson, R.O.; Laymon, C.M.; Wender, S.A.

1990-01-01

Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n,α), (n,nα), (n,p), (n,np), (n,nnp) and (n,xn) for 1 ≤ x ≤ 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation function measurements and greatly extends the energy range for such data. The results of these measurements will provide a database for interpretation of gamma-ray spectra from the planned Mars Observer mission, aid in radiation transport calculations, allow verification of nuclear reaction models, and improve the evaluated neutron reaction data base

High-lying neutron hole strengths observed in pick-up reactions

International Nuclear Information System (INIS)

Gales, S.

1980-01-01

Neutron-hole states in orbits well below the Fermi surface have been observed in a number of medium-heavy nuclei from A=90 to 209 using one nucleon pick-up reactions. The excitation energies, angular distributions of such broad and enhanced structures will be discussed. The fragmentation of the neutron-hole strengths as well as the spreading of such simple mode of excitations into more complex states are compared to recent calculations within the quasiparticle-phonon or the single particle-vibration coupling nuclear models. We report on recent measurements of J for inner-hole states in 89 Zr and 115 Sn 119 Sn using the analyzing power of the (p,d) and (d,t) reactions. Large enhancement of cross-sections are observed at high excitation energy in the study of the (p,t) reactions on Zr, Cd, Sn, Te and Sm isotopes. The systematic features of such high-lying excitation are related to the ones observed in one neutron pick-up experiments. The origin of such concentration of two neutron-hole strengths in Cd and Sn isotopes will be discussed. Preliminary results obtained in the study of the (α, 6 He) reaction at 218 MeV incident energy on 90 Zr, 118 Sn and 208 Pb targets are presented and compared to the (p,t) results. Finally the properties of hole-analog states populated in neutron pick-up reactions (from 90 Zr to 208 Pb) will be presented

High-resolution satellite image segmentation using Hölder exponents

Indian Academy of Sciences (India)

Keywords. High resolution image; texture analysis; segmentation; IKONOS; Hölder exponent; cluster. ... are that. • it can be used as a tool to measure the roughness ... uses reinforcement learning to learn the reward values of ..... The numerical.

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, A.V.; Veldhuizen, E.J. van; Westerberg, L.; Lyapin, V.G.; Aleklett, K.; Loveland, W.; Bondorf, J.; Jakobsson, B.; Whitlow, H.J.; El Bouanani, M

2000-10-01

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate (MCP) time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of {approx}35 keV/nucleon from the interactions of 400 MeV/nucleon {sup 16}O with {sup nat}Xe gas targets.

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products

International Nuclear Information System (INIS)

Kuznetsov, A.V.; Loveland, W.; Jakobsson, B.; Whitlow, H.J.; Bouanani, M. El; Univ. of North Texas, Denton, TX

2000-01-01

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of ∼ 35 keV/nucleon from the interactions of 400 MeV/nucleon 16 O with nat Xe gas targets

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, A.V. [V.G.Khlopin Radium Institute, St. Petersburg (Russian Federation); Uppsala Univ. (Sweden). The Svedberg Lab.; Veldhuizen, E.J. van; Aleklett, K. [Uppsala Univ., (Sweden). Dept. of Radiation Sciences; Westerberg, L. [Uppsala University (Sweden). The Svedberg Lab.; Lyapin, V.G. [V.G.Khlopin Radium Institute, St. Petersburg (Russian Federation); Loveland, W. [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry; Bondorf, J. [Niels Bohr Inst., Copenhagen (Denmark); Jakobsson, B. [Lund Univ. (Sweden). Dept. of Physics; Whitlow, H.J. [Lund Univ. (Sweden). Dept. of Nuclear Physics; Bouanani, M. El [Lund Univ. (Sweden). Dept. of Nuclear Physics; Univ. of North Texas, Denton, TX (United States). Dept. of Physics

2000-07-01

A compact Ultra High Vacuum (UHV) compatible instrument for time of flight energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of {approx} 35 keV/nucleon from the interactions of 400 MeV/nucleon {sup 16}O with {sup nat} Xe gas targets.

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products

International Nuclear Information System (INIS)

Kuznetsov, A.V.; Veldhuizen, E.J. van; Westerberg, L.; Lyapin, V.G.; Aleklett, K.; Loveland, W.; Bondorf, J.; Jakobsson, B.; Whitlow, H.J.; El Bouanani, M.

2000-01-01

A compact Ultra-High Vacuum (UHV) compatible instrument for time of flight-energy measurements of slow heavy reaction products from nuclear reactions has been designed and tested at the CELSIUS storage ring in Uppsala. The construction is based on MicroChannel Plate (MCP) time detectors of the electron mirror type and silicon p-i-n diodes, and permits the detectors to be stacked side-by-side to achieve large solid angle coverage. This kind of telescope measures the Time of Flight (ToF) and Energy (E) of the particle from which one can reconstruct mass. The combination of an ultra-thin cluster gas-jet target and thin carbon emitter foils allows one to measure heavy residues down to an energy of ∼35 keV/nucleon from the interactions of 400 MeV/nucleon 16 O with nat Xe gas targets

A High Resolution Capacitive Sensing System for the Measurement of Water Content in Crude Oil

Science.gov (United States)

Aslam, Muhammad Zubair; Tang, Tong Boon

2014-01-01

This paper presents the design of a non-intrusive system to measure ultra-low water content in crude oil. The system is based on a capacitance to phase angle conversion method. Water content is measured with a capacitance sensor comprising two semi-cylindrical electrodes mounted on the outer side of a glass tube. The presence of water induces a capacitance change that in turn converts into a phase angle, with respect to a main oscillator. A differential sensing technique is adopted not only to ensure high immunity against temperature variation and background noise, but also to eliminate phase jitter and amplitude variation of the main oscillator that could destabilize the output. The complete capacitive sensing system was implemented in hardware and experiment results using crude oil samples demonstrated that a resolution of ±50 ppm of water content in crude oil was achieved by the proposed design. PMID:24967606

A High Resolution Capacitive Sensing System for the Measurement of Water Content in Crude Oil

Directory of Open Access Journals (Sweden)

Muhammad Zubair Aslam

2014-06-01

Full Text Available This paper presents the design of a non-intrusive system to measure ultra-low water content in crude oil. The system is based on a capacitance to phase angle conversion method. Water content is measured with a capacitance sensor comprising two semi-cylindrical electrodes mounted on the outer side of a glass tube. The presence of water induces a capacitance change that in turn converts into a phase angle, with respect to a main oscillator. A differential sensing technique is adopted not only to ensure high immunity against temperature variation and background noise, but also to eliminate phase jitter and amplitude variation of the main oscillator that could destabilize the output. The complete capacitive sensing system was implemented in hardware and experiment results using crude oil samples demonstrated that a resolution of ±50 ppm of water content in crude oil was achieved by the proposed design.

High-resolution flood modeling of urban areas using MSN_Flood

Directory of Open Access Journals (Sweden)

Michael Hartnett

2017-07-01

Full Text Available Although existing hydraulic models have been used to simulate and predict urban flooding, most of these models are inadequate due to the high spatial resolution required to simulate flows in urban floodplains. Nesting high-resolution subdomains within coarser-resolution models is an efficient solution for enabling simultaneous calculation of flooding due to tides, surges, and high river flows. MSN_Flood has been developed to incorporate moving boundaries around nested domains, permitting alternate flooding and drying along the boundary and in the interior of the domain. Ghost cells adjacent to open boundary cells convert open boundaries, in effect, into internal boundaries. The moving boundary may be multi-segmented and non-continuous, with recirculating flow across the boundary. When combined with a bespoke adaptive interpolation scheme, this approach facilitates a dynamic internal boundary. Based on an alternating-direction semi-implicit finite difference scheme, MSN_Flood was used to hindcast a major flood event in Cork City resulting from the combined pressures of fluvial, tidal, and storm surge processes. The results show that the model is computationally efficient, as the 2-m high-resolution nest is used only in the urban flooded region. Elsewhere, lower-resolution nests are used. The results also show that the model is highly accurate when compared with measured data. The model is capable of incorporating nested sub-domains when the nested boundary is multi-segmented and highly complex with lateral gradients of elevation and velocities. This is a major benefit when modelling urban floodplains at very high resolution.

High frequency, high time resolution time-to-digital converter employing passive resonating circuits.

Science.gov (United States)

Ripamonti, Giancarlo; Abba, Andrea; Geraci, Angelo

2010-05-01

A method for measuring time intervals accurate to the picosecond range is based on phase measurements of oscillating waveforms synchronous with their beginning and/or end. The oscillation is generated by triggering an LC resonant circuit, whose capacitance is precharged. By using high Q resonators and a final active quenching of the oscillation, it is possible to conjugate high time resolution and a small measurement time, which allows a high measurement rate. Methods for fast analysis of the data are considered and discussed with reference to computing resource requirements, speed, and accuracy. Experimental tests show the feasibility of the method and a time accuracy better than 4 ps rms. Methods aimed at further reducing hardware resources are finally discussed.

High frequency, high time resolution time-to-digital converter employing passive resonating circuits

International Nuclear Information System (INIS)

Ripamonti, Giancarlo; Abba, Andrea; Geraci, Angelo

2010-01-01

A method for measuring time intervals accurate to the picosecond range is based on phase measurements of oscillating waveforms synchronous with their beginning and/or end. The oscillation is generated by triggering an LC resonant circuit, whose capacitance is precharged. By using high Q resonators and a final active quenching of the oscillation, it is possible to conjugate high time resolution and a small measurement time, which allows a high measurement rate. Methods for fast analysis of the data are considered and discussed with reference to computing resource requirements, speed, and accuracy. Experimental tests show the feasibility of the method and a time accuracy better than 4 ps rms. Methods aimed at further reducing hardware resources are finally discussed.

Time resolution performance studies of contemporary high speed photomultipliers

International Nuclear Information System (INIS)

Leskovar, B.; Lo, C.C.

1977-01-01

The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single photoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed RCS 8850 and C31024 high speed photomultipliers. Descriptions are given of both the measuring techniques and the measuring systems

Comparison of high resolution computed tomography and pulmonary function tests in diagnosis of mild emphysema

International Nuclear Information System (INIS)

Kuwano, Kazuyoshi; Matsuba, Kenichi; Ikeda, Togo

1989-01-01

To assess the ability of high resolution CT scan and pulmonary function tests in detecting and grading mild emphysema, we correlated the high resolution CT scan and pulmonary function tests with the pathologic grade of emphysema and the destructive index of lung specimens from 42 patients undergoing thoracotomy for solitary pulmonary nodules. Using the high resolution CT scan, we could identify the pathologic grade of mild and moderate emphysema. By measuring diffusing capacity per unit alveolar gas volume (DLco/VA), it seemed to be possible to detect the mildest degree of alveolar destruction assessed by the destructive index, which was not detected by high resolution CT scan. The reason for these results seemed to be that we assessed the severity of emphysema by detecting the air space enlargement on high resolution CT scan images caused by the destruction of alveolar walls, which were detectable by measuring DLco/VA. We conclude that it is possible to detect mild emphysema using the combination of high resolution CT scan and pulmomary function tests. (author)

Characterization Of Ocean Wind Vector Retrievals Using ERS-2 High-Resolution Long-Term Dataset And Buoy Measurements

Science.gov (United States)

Polverari, F.; Talone, M.; Crapolicchio, R. Levy, G.; Marzano, F.

2013-12-01

The European Remote-sensing Satellite (ERS)-2 scatterometer provides wind retrievals over Ocean. To satisfy the needs of high quality and homogeneous set of scatterometer measurements, the European Space Agency (ESA) has developed the project Advanced Scatterometer Processing System (ASPS) with which a long-term dataset of new ERS-2 wind products, with an enhanced resolution of 25km square, has been generated by the reprocessing of the entire ERS mission. This paper presents the main results of the validation work of such new dataset using in situ measurements provided by the Prediction and Research Moored Array in the Tropical Atlantic (PIRATA). The comparison indicates that, on average, the scatterometer data agree well with buoys measurements, however the scatterometer tends to overestimates lower winds and underestimates higher winds.

High energy resolution and first time-dependent positron annihilation induced Auger electron spectroscopty

International Nuclear Information System (INIS)

Mayer, Jakob

2010-01-01

It was the aim of this thesis to improve the existing positron annihilation induced Auger spectrometer at the highly intense positron source NEPOMUC (NEutron induced POsitron source MUniCh) in several ways: Firstly, the measurement time for a single spectrum should be reduced from typically 12 h to roughly 1 h or even less. Secondly, the energy resolution, which amounted to ΔE/E∼10%, should be increased by at least one order of magnitude in order to make high resolution positron annihilation induced Auger spectroscopy (PAES)-measurements of Auger transitions possible and thus deliver more information about the nature of the Auger process. In order to achieve these objectives, the PAES spectrometer was equipped with a new electron energy analyzer. For its ideal operation all other components of the Auger analysis chamber had to be adapted. Particularly the sample manipulation and the positron beam guidance had to be renewed. Simulations with SIMION registered ensured the optimal positron lens parameters. After the adjustment of the new analyzer and its components, first measurements illustrated the improved performance of the PAES setup: Firstly, the measurement time for short overview measurements was reduced from 3 h to 420 s. The measurement time for more detailed Auger spectra was shortened from 12 h to 80 min. Secondly, even with the reduced measurement time, the signal to noise ratio was also enhanced by one order of magnitude. Finally, the energy resolution was improved to ΔE/E 2,3 VV-transition with PAES. Thus, within this thesis two objectives were achieved: Firstly, the PAES spectrometer was renewed and improved by at least one order of magnitude with respect to the signal to noise ratio, the measurement time and the energy resolution. Secondly, several measurements have been carried out, demonstrating the high performance of the spectrometer. Amongst them are first dynamic PAES measurements and a high resolution measurement of the CuM 2,3 VV

High Time Resolution Measurements of VOCs from Vehicle Cold Starts: The Air Toxic Cold Start Pulse

Science.gov (United States)

Jobson, B. T.; Huangfu, Y.; Vanderschelden, G. S.

2017-12-01

Pollutants emitted during motor vehicle cold starts, especially in winter in some climates, is a significant source of winter time air pollution. While data exist for CO, NO, and total hydrocarbon emissions from federal testing procedures for vehicle emission certification, little is known about the emission rates of individual volatile organic compounds, in particular the air toxics benzene, formaldehyde, and acetaldehyde. Little is known about the VOC speciation and temperature dependence for cold starts. The US EPA vehicle emission model MOVES assumes that cold start emissions have the same speciation profile as running emissions. We examined this assumption by measuring cold start exhaust composition for 4 vehicles fueled with E10 gasoline over a temperature range of -4°C to 10°C in winter of 2015. The extra cold start emissions were determined by comparison with emissions during engine idling. In addition to CO and NOx measurements a proton transfer reaction mass spectrometer was used to measure formaldehyde, acetaldehyde, benzene, toluene, and C2-alkylbenzenes at high time resolution to compare with the cold start emission speciation profiles used in the EPA MOVES2014 model. The results show that after the vehicle was started, CO mixing ratios can reach a few percent of the exhaust and then drop to several ppmv within 2 minutes of idling, while NOx showed different temporal behaviors among the four vehicles. VOCs displayed elevated levels during cold start and the peak mixing ratios can be two orders higher than idling phase levels. Molar emission ratios relative to toluene were used to compare with the emission ratio used in MOVES2014 and we found the formaldehyde-to-toluene emission ratio was about 0.19, which is 5 times higher than the emission ratio used in MOVES2014 and the acetaldehyde-to-toluene emission ratios were 0.86-0.89, which is 8 times higher than the ones in MOVES2014. The C2-alkylbenzene-to-toluene ratio agreed well with moves. Our results

Gamma-ray emission spectrum from thermonuclear fusion reactions without intrinsic broadening

DEFF Research Database (Denmark)

Nocente, M.; Källne, J.; Salewski, Mirko

2015-01-01

First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution instrume......First principle calculations of the gamma-ray energy spectrum arising from thermonuclear reactions without intrinsic broadening in fusion plasmas are presented, extending the theoretical framework needed to interpret measurements up to the accuracy level enabled by modern high resolution...... instruments. An analytical formula for the spectrum from Maxwellian plasmas, which extends to higher temperatures than the results previously available in the literature, has been derived and used to discuss the assumptions and limitations of earlier models. In case of radio-frequency injection, numerical...... results based on a Monte Carlo method are provided, focusing in particular on improved relations between the peak shift and width from the reaction and the temperature of protons accelerated by radio-frequency heating.The results presented in this paper significantly improve the accuracy of diagnostic...

High-resolution spatiotemporal strain mapping reveals non-uniform deformation in micropatterned elastomers

Science.gov (United States)

Aksoy, B.; Rehman, A.; Bayraktar, H.; Alaca, B. E.

2017-04-01

Micropatterns are generated on a vast selection of polymeric substrates for various applications ranging from stretchable electronics to cellular mechanobiological systems. When these patterned substrates are exposed to external loading, strain field is primarily affected by the presence of microfabricated structures and similarly by fabrication-related defects. The capturing of such nonhomogeneous strain fields is of utmost importance in cases where study of the mechanical behavior with a high spatial resolution is necessary. Image-based non-contact strain measurement techniques are favorable and have recently been extended to scanning tunneling microscope and scanning electron microscope images for the characterization of mechanical properties of metallic materials, e.g. steel and aluminum, at the microscale. A similar real-time analysis of strain heterogeneity in elastomers is yet to be achieved during the entire loading sequence. The available measurement methods for polymeric materials mostly depend on cross-head displacement or precalibrated strain values. Thus, they suffer either from the lack of any real-time analysis, spatiotemporal distribution or high resolution in addition to a combination of these factors. In this work, these challenges are addressed by integrating a tensile stretcher with an inverted optical microscope and developing a subpixel particle tracking algorithm. As a proof of concept, the patterns with a critical dimension of 200 µm are generated on polydimethylsiloxane substrates and strain distribution in the vicinity of the patterns is captured with a high spatiotemporal resolution. In the field of strain measurement, there is always a tradeoff between minimum measurable strain value and spatial resolution. Current noncontact techniques on elastomers can deliver a strain resolution of 0.001% over a minimum length of 5 cm. More importantly, inhomogeneities within this quite large region cannot be captured. The proposed technique can

High-resolution spatiotemporal strain mapping reveals non-uniform deformation in micropatterned elastomers

International Nuclear Information System (INIS)

Aksoy, B; Alaca, B E; Rehman, A; Bayraktar, H

2017-01-01

Micropatterns are generated on a vast selection of polymeric substrates for various applications ranging from stretchable electronics to cellular mechanobiological systems. When these patterned substrates are exposed to external loading, strain field is primarily affected by the presence of microfabricated structures and similarly by fabrication-related defects. The capturing of such nonhomogeneous strain fields is of utmost importance in cases where study of the mechanical behavior with a high spatial resolution is necessary. Image-based non-contact strain measurement techniques are favorable and have recently been extended to scanning tunneling microscope and scanning electron microscope images for the characterization of mechanical properties of metallic materials, e.g. steel and aluminum, at the microscale. A similar real-time analysis of strain heterogeneity in elastomers is yet to be achieved during the entire loading sequence. The available measurement methods for polymeric materials mostly depend on cross-head displacement or precalibrated strain values. Thus, they suffer either from the lack of any real-time analysis, spatiotemporal distribution or high resolution in addition to a combination of these factors. In this work, these challenges are addressed by integrating a tensile stretcher with an inverted optical microscope and developing a subpixel particle tracking algorithm. As a proof of concept, the patterns with a critical dimension of 200 µ m are generated on polydimethylsiloxane substrates and strain distribution in the vicinity of the patterns is captured with a high spatiotemporal resolution. In the field of strain measurement, there is always a tradeoff between minimum measurable strain value and spatial resolution. Current noncontact techniques on elastomers can deliver a strain resolution of 0.001% over a minimum length of 5 cm. More importantly, inhomogeneities within this quite large region cannot be captured. The proposed technique can

Ultra-high resolution AMOLED

Science.gov (United States)

Wacyk, Ihor; Prache, Olivier; Ghosh, Amal

2011-06-01

AMOLED microdisplays continue to show improvement in resolution and optical performance, enhancing their appeal for a broad range of near-eye applications such as night vision, simulation and training, situational awareness, augmented reality, medical imaging, and mobile video entertainment and gaming. eMagin's latest development of an HDTV+ resolution technology integrates an OLED pixel of 3.2 × 9.6 microns in size on a 0.18 micron CMOS backplane to deliver significant new functionality as well as the capability to implement a 1920×1200 microdisplay in a 0.86" diagonal area. In addition to the conventional matrix addressing circuitry, the HDTV+ display includes a very lowpower, low-voltage-differential-signaling (LVDS) serialized interface to minimize cable and connector size as well as electromagnetic emissions (EMI), an on-chip set of look-up-tables for digital gamma correction, and a novel pulsewidth- modulation (PWM) scheme that together with the standard analog control provides a total dimming range of 0.05cd/m2 to 2000cd/m2 in the monochrome version. The PWM function also enables an impulse drive mode of operation that significantly reduces motion artifacts in high speed scene changes. An internal 10-bit DAC ensures that a full 256 gamma-corrected gray levels are available across the entire dimming range, resulting in a measured dynamic range exceeding 20-bits. This device has been successfully tested for operation at frame rates ranging from 30Hz up to 85Hz. This paper describes the operational features and detailed optical and electrical test results for the new AMOLED WUXGA resolution microdisplay.

Air pollutant dispersion from a large semi-enclosed stadium in an urban area: high-resolution CFD modeling versus full-scale measurements

NARCIS (Netherlands)

Hooff, van T.A.J.; Blocken, B.J.E.; Seppelt, R.; Voinov, A.A.; Lange, S.; Bankamp, D.

2012-01-01

Abstract: High-resolution CFD simulations and full-scale measurements have been performed to assess the dispersion of air pollutants (CO2) from the large semi-enclosed Amsterdam ArenA football stadium. The dispersion process is driven by natural ventilation by the urban wind flow and by buoyancy,

High resolution sequence stratigraphy in China

International Nuclear Information System (INIS)

Zhang Shangfeng; Zhang Changmin; Yin Yanshi; Yin Taiju

2008-01-01

Since high resolution sequence stratigraphy was introduced into China by DENG Hong-wen in 1995, it has been experienced two development stages in China which are the beginning stage of theory research and development of theory research and application, and the stage of theoretical maturity and widely application that is going into. It is proved by practices that high resolution sequence stratigraphy plays more and more important roles in the exploration and development of oil and gas in Chinese continental oil-bearing basin and the research field spreads to the exploration of coal mine, uranium mine and other strata deposits. However, the theory of high resolution sequence stratigraphy still has some shortages, it should be improved in many aspects. The authors point out that high resolution sequence stratigraphy should be characterized quantitatively and modelized by computer techniques. (authors)

Development of AMS high resolution injector system

International Nuclear Information System (INIS)

Bao Yiwen; Guan Xialing; Hu Yueming

2008-01-01

The Beijing HI-13 tandem accelerator AMS high resolution injector system was developed. The high resolution energy achromatic system consists of an electrostatic analyzer and a magnetic analyzer, which mass resolution can reach 600 and transmission is better than 80%. (authors)

MIPAS-ENVISAT limb-sounding measurements: trade-off study for improvement of horizontal resolution.

Science.gov (United States)

Ridolfi, Marco; Magnani, Luca; Carlotti, Massimo; Dinelli, Bianca Maria

2004-11-01

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is a limb-scanning spectrometer that has operated onboard the Environmental Satellite since the end of March 2002. Common features of limb-scanning experiments are both high vertical resolution and poor horizontal resolution. We exploit the two-dimensional geo-fit retrieval approach [Appl. Opt. 40, 1872-1875 (2001)] to investigate the possibility of improving the horizontal resolution of MIPAS measurements. Two different strategies are considered for this purpose, one exploiting the possibility (offered by the geo-fit analysis method) for an arbitrary definition of the retrieval grid, the other based on the possibility of saving measurement time by degrading the spectral resolution of the interferometer. The performances of the two strategies are compared in terms of the trade-off between the attained horizontal resolution and the retrieval precision. We find that for ozone it is possible to improve by a factor of 2 the horizontal resolution, which in the nominal measurement plan is approximately 530 km. This improvement corresponds to a degradation of the retrieval precision, which on average varies from a factor of 1.4 to 2.5, depending on the adopted spectral resolution.

Resolution enhancement of low quality videos using a high-resolution frame

NARCIS (Netherlands)

Pham, T.Q.; Van Vliet, L.J.; Schutte, K.

2006-01-01

This paper proposes an example-based Super-Resolution (SR) algorithm of compressed videos in the Discrete Cosine Transform (DCT) domain. Input to the system is a Low-Resolution (LR) compressed video together with a High-Resolution (HR) still image of similar content. Using a training set of

Development of an Internally-Calibrated Wide-Band Airborne Microwave Radiometer to Provide High-Resolution Wet-Tropospheric Path Delay Measurements for SWOT (HAMMR - High-frequency Airborne Microwave and Millimeter-wave Radiometer)

Data.gov (United States)

National Aeronautics and Space Administration — Development of an Internally-Calibrated Wide-Band Airborne Microwave Radiometer to Provide High-Resolution Wet-Tropospheric Path Delay Measurements for SWOT (HAMMR -...

Resolving mass flux at high spatial and temporal resolution using GRACE intersatellite measurements

DEFF Research Database (Denmark)

Rowlands, D. D.; Luthcke, S. B.; Klosko, S. M.

2005-01-01

resolution. Using 4° × 4° blocks at 10-day intervals, we estimate the mass of surplus or deficit water over a 52° × 60° grid centered on the Amazon basin for July 2003. We demonstrate that the recovered signals are coherent and correlate well with the expected hydrological signal....... the estimation of static monthly parameters. Through an analysis of the GRACE data residuals, we show that the fundamental temporal and spatial resolution of the GRACE data is 10 days and 400 km. We present an approach similar in concept to altimetric methods that recovers submonthly mass flux at a high spatial...

Large microcalorimeter arrays for high-resolution X- and gamma-rayspectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hoover, A.S., E-mail: ahoover@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hoteling, N.; Rabin, M.W. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Ullom, J.N.; Bennett, D.A. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Karpius, P.J.; Vo, D.T. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Doriese, W.B.; Hilton, G.C.; Horansky, R.D.; Irwin, K.D.; Kotsubo, V. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Lee, D.W. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Vale, L.R. [National Institute of Standards and Technology, Boulder, CO 80305 (United States)

2011-10-01

Microcalorimeter detectors provide unprecedented energy resolution for the measurement of X-rays and soft gamma-rays. Energy resolution in the 100 keV region can be up to an order of magnitude better than planar high-purity germanium (HPGe) detectors. The technology is well-suited to analysis of materials with complex spectra presenting closely spaced photopeaks. One application area is the measurement and assay of nuclear materials for safeguards and fuel cycle applications. In this paper, we discuss the operation and performance of a 256-pixel array, and present results of a head-to-head comparison of isotopic determination measurements with high-purity germanium using a plutonium standard. We show that the uncertainty of a single measurement is smaller for the microcalorimeter data compared to the HPGe data when photopeak areas are equal. We identify several key areas where analysis codes can be optimized that will likely lead to improvement in the microcalorimeter performance.

High-resolution x-ray imaging using a structured scintillator

Energy Technology Data Exchange (ETDEWEB)

Hormozan, Yashar, E-mail: hormozan@kth.se; Sychugov, Ilya; Linnros, Jan [Materials and Nano Physics, School of Information and Communication Technology, KTH Royal Institute of Technology, Electrum 229, Kista, Stockholm SE-16440 (Sweden)

2016-02-15

Purpose: In this study, the authors introduce a new generation of finely structured scintillators with a very high spatial resolution (a few micrometers) compared to conventional scintillators, yet maintaining a thick absorbing layer for improved detectivity. Methods: Their concept is based on a 2D array of high aspect ratio pores which are fabricated by ICP etching, with spacings (pitches) of a few micrometers, on silicon and oxidation of the pore walls. The pores were subsequently filled by melting of powdered CsI(Tl), as the scintillating agent. In order to couple the secondary emitted photons of the back of the scintillator array to a CCD device, having a larger pixel size than the pore pitch, an open optical microscope with adjustable magnification was designed and implemented. By imaging a sharp edge, the authors were able to calculate the modulation transfer function (MTF) of this finely structured scintillator. Results: The x-ray images of individually resolved pores suggest that they have been almost uniformly filled, and the MTF measurements show the feasibility of a few microns spatial resolution imaging, as set by the scintillator pore size. Compared to existing techniques utilizing CsI needles as a structured scintillator, their results imply an almost sevenfold improvement in resolution. Finally, high resolution images, taken by their detector, are presented. Conclusions: The presented work successfully shows the functionality of their detector concept for high resolution imaging and further fabrication developments are most likely to result in higher quantum efficiencies.

High resolution, high speed ultrahigh vacuum microscopy

International Nuclear Information System (INIS)

Poppa, Helmut

2004-01-01

The history and future of transmission electron microscopy (TEM) is discussed as it refers to the eventual development of instruments and techniques applicable to the real time in situ investigation of surface processes with high resolution. To reach this objective, it was necessary to transform conventional high resolution instruments so that an ultrahigh vacuum (UHV) environment at the sample site was created, that access to the sample by various in situ sample modification procedures was provided, and that in situ sample exchanges with other integrated surface analytical systems became possible. Furthermore, high resolution image acquisition systems had to be developed to take advantage of the high speed imaging capabilities of projection imaging microscopes. These changes to conventional electron microscopy and its uses were slowly realized in a few international laboratories over a period of almost 40 years by a relatively small number of researchers crucially interested in advancing the state of the art of electron microscopy and its applications to diverse areas of interest; often concentrating on the nucleation, growth, and properties of thin films on well defined material surfaces. A part of this review is dedicated to the recognition of the major contributions to surface and thin film science by these pioneers. Finally, some of the important current developments in aberration corrected electron optics and eventual adaptations to in situ UHV microscopy are discussed. As a result of all the path breaking developments that have led to today's highly sophisticated UHV-TEM systems, integrated fundamental studies are now possible that combine many traditional surface science approaches. Combined investigations to date have involved in situ and ex situ surface microscopies such as scanning tunneling microscopy/atomic force microscopy, scanning Auger microscopy, and photoemission electron microscopy, and area-integrating techniques such as x-ray photoelectron

A high resolution solar atlas for fluorescence calculations

Science.gov (United States)

Hearn, M. F.; Ohlmacher, J. T.; Schleicher, D. G.

1983-01-01

The characteristics required of a solar atlas to be used for studying the fluorescence process in comets are examined. Several sources of low resolution data were combined to provide an absolutely calibrated spectrum from 2250 A to 7000A. Three different sources of high resolution data were also used to cover this same spectral range. The low resolution data were then used to put each high resolution spectrum on an absolute scale. The three high resolution spectra were then combined in their overlap regions to produce a single, absolutely calibrated high resolution spectrum over the entire spectral range.

Isotope specific resolution recovery image reconstruction in high resolution PET imaging

OpenAIRE

Kotasidis Fotis A.; Kotasidis Fotis A.; Angelis Georgios I.; Anton-Rodriguez Jose; Matthews Julian C.; Reader Andrew J.; Reader Andrew J.; Zaidi Habib; Zaidi Habib; Zaidi Habib

2014-01-01

Purpose: Measuring and incorporating a scanner specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However due to the short half life of clinically used isotopes other long lived isotopes not used in clinical practice are used to perform the PSF measurements. As such non optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction usuall...

Adaptive optics with pupil tracking for high resolution retinal imaging.

Science.gov (United States)

Sahin, Betul; Lamory, Barbara; Levecq, Xavier; Harms, Fabrice; Dainty, Chris

2012-02-01

Adaptive optics, when integrated into retinal imaging systems, compensates for rapidly changing ocular aberrations in real time and results in improved high resolution images that reveal the photoreceptor mosaic. Imaging the retina at high resolution has numerous potential medical applications, and yet for the development of commercial products that can be used in the clinic, the complexity and high cost of the present research systems have to be addressed. We present a new method to control the deformable mirror in real time based on pupil tracking measurements which uses the default camera for the alignment of the eye in the retinal imaging system and requires no extra cost or hardware. We also present the first experiments done with a compact adaptive optics flood illumination fundus camera where it was possible to compensate for the higher order aberrations of a moving model eye and in vivo in real time based on pupil tracking measurements, without the real time contribution of a wavefront sensor. As an outcome of this research, we showed that pupil tracking can be effectively used as a low cost and practical adaptive optics tool for high resolution retinal imaging because eye movements constitute an important part of the ocular wavefront dynamics.

Integrated High Resolution Monitoring of Mediterranean vegetation

Science.gov (United States)

Cesaraccio, Carla; Piga, Alessandra; Ventura, Andrea; Arca, Angelo; Duce, Pierpaolo; Mereu, Simone

2017-04-01

The study of the vegetation features in a complex and highly vulnerable ecosystems, such as Mediterranean maquis, leads to the need of using continuous monitoring systems at high spatial and temporal resolution, for a better interpretation of the mechanisms of phenological and eco-physiological processes. Near-surface remote sensing techniques are used to quantify, at high temporal resolution, and with a certain degree of spatial integration, the seasonal variations of the surface optical and radiometric properties. In recent decades, the design and implementation of global monitoring networks involved the use of non-destructive and/or cheaper approaches such as (i) continuous surface fluxes measurement stations, (ii) phenological observation networks, and (iii) measurement of temporal and spatial variations of the vegetation spectral properties. In this work preliminary results from the ECO-SCALE (Integrated High Resolution Monitoring of Mediterranean vegetation) project are reported. The project was manly aimed to develop an integrated system for environmental monitoring based on digital photography, hyperspectral radiometry , and micrometeorological techniques during three years of experimentation (2013-2016) in a Mediterranean site of Italy (Capo Caccia, Alghero). The main results concerned the analysis of chromatic coordinates indices from digital images, to characterized the phenological patterns for typical shrubland species, determining start and duration of the growing season, and the physiological status in relation to different environmental drought conditions; then the seasonal patterns of canopy phenology, was compared to NEE (Net Ecosystem Exchange) patterns, showing similarities. However, maximum values of NEE and ER (Ecosystem respiration), and short term variation, seemed mainly tuned by inter annual pattern of meteorological variables, in particular of temperature recorded in the months preceding the vegetation green-up. Finally, green signals

CeBr3 as a room-temperature, high-resolution gamma-ray detector

International Nuclear Information System (INIS)

Guss, Paul; Reed, Michael; Yuan Ding; Reed, Alexis; Mukhopadhyay, Sanjoy

2009-01-01

Cerium bromide (CeBr 3 ) has become a material of interest in the race for high-resolution gamma-ray spectroscopy at room temperature. This investigation quantified the potential of CeBr 3 as a room-temperature, high-resolution gamma-ray detector. The performance of CeBr 3 crystals was compared to other scintillation crystals of similar dimensions and detection environments. Comparison of self-activity of CeBr 3 to cerium-doped lanthanum tribromide (LaBr 3 :Ce) was performed. Energy resolution and relative intrinsic efficiency were measured and are presented.

Determination of the resonance parameters for 232Th from high resolution transmission and capture measurements at GELINA

International Nuclear Information System (INIS)

Brusegan, A.; Schillebeeckx, P.; Lobo, G.; Borella, A.; Volev, K.; Janeva, N.

2003-01-01

To deduce the resonance parameters for 232 Th in the resolved resonance region, high resolution transmission and capture measurements are being performed. The measurements are performed at the Time-Of-Flight facility GELINA. A comparison of experimental data resulting from capture (top) and transmission (bottom) are shown. The transmission measurements are performed at a 50 m flight path. The neutron are detected with a 0.25' thick lithium glass (NE912) placed in an Al sphere and viewed by a 5' EMI KQB photomultiplier orthogonal to the neutron beam axis. The injection of a stabilised light pulse in the detector during the measurements provided an efficient tool to control to better than 1% the gain of the entire electronics. The experimental set-up includes a sample-changer, placed at 23 m from the neutron source, which is driven by the acquisition system. The determination of the flight path length, was based on transmission of the 6.673 eV resonance of 238 U. We summarise, for the different energy regions of interest, the scheduled measurement conditions: the operation frequency of the accelerator and the target thickness. A simultaneous analysis of the data using REFIT will result in the resonance parameters from 0 to 4 keV. We show the result of a resonance shape analysis for the resonances at 21.8 and 23.5 eV. The resulting resonance parameters are important for the energy calibration and normalisation of the capture measurements in both the resolved and unresolved resonance region. The capture measurements are completed and were performed at a 60 m flight path. The sample consisted of a metallic natural thorium disc of 8 cm diameter and 1.0 mm thick, corresponding to a thickness of 3.176 10 -3 at/b. The neutron flux was measured with an ionisation chamber loaded with three back-to-back layers of about 40 μg/cm 2 10 B. The gamma rays, originating from the 232 Th(n,γ) reaction, were detected by four C 6 D 6 -based liquid scintillators (NE230) placed

Paracoccidioidomycosis: High-resolution computed tomography-pathologic correlation

International Nuclear Information System (INIS)

Marchiori, Edson; Valiante, Paulo Marcos; Mano, Claudia Mauro; Zanetti, Glaucia; Escuissato, Dante L.; Souza, Arthur Soares; Capone, Domenico

2011-01-01

Objective: The purpose of this study was to describe the high-resolution computed tomography (HRCT) features of pulmonary paracoccidioidomycosis and to correlate them with pathologic findings. Methods: The study included 23 adult patients with pulmonary paracoccidioidomycosis. All patients had undergone HRCT, and the images were retrospectively analyzed by two chest radiologists, who reached decisions by consensus. An experienced lung pathologist reviewed all pathological specimens. The HRCT findings were correlated with histopathologic data. Results: The predominant HRCT findings included areas of ground-glass opacities, nodules, interlobular septal thickening, airspace consolidation, cavitation, and fibrosis. The main pathological features consisted of alveolar and interlobular septal inflammatory infiltration, granulomas, alveolar exudate, cavitation secondary to necrosis, and fibrosis. Conclusion: Paracoccidioidomycosis can present different tomography patterns, which can involve both the interstitium and the airspace. These abnormalities can be pathologically correlated with inflammatory infiltration, granulomatous reaction, and fibrosis.

Maximum likelihood positioning algorithm for high-resolution PET scanners

International Nuclear Information System (INIS)

Gross-Weege, Nicolas; Schug, David; Hallen, Patrick; Schulz, Volkmar

2016-01-01

Purpose: In high-resolution positron emission tomography (PET), lightsharing elements are incorporated into typical detector stacks to read out scintillator arrays in which one scintillator element (crystal) is smaller than the size of the readout channel. In order to identify the hit crystal by means of the measured light distribution, a positioning algorithm is required. One commonly applied positioning algorithm uses the center of gravity (COG) of the measured light distribution. The COG algorithm is limited in spatial resolution by noise and intercrystal Compton scatter. The purpose of this work is to develop a positioning algorithm which overcomes this limitation. Methods: The authors present a maximum likelihood (ML) algorithm which compares a set of expected light distributions given by probability density functions (PDFs) with the measured light distribution. Instead of modeling the PDFs by using an analytical model, the PDFs of the proposed ML algorithm are generated assuming a single-gamma-interaction model from measured data. The algorithm was evaluated with a hot-rod phantom measurement acquired with the preclinical HYPERION II D PET scanner. In order to assess the performance with respect to sensitivity, energy resolution, and image quality, the ML algorithm was compared to a COG algorithm which calculates the COG from a restricted set of channels. The authors studied the energy resolution of the ML and the COG algorithm regarding incomplete light distributions (missing channel information caused by detector dead time). Furthermore, the authors investigated the effects of using a filter based on the likelihood values on sensitivity, energy resolution, and image quality. Results: A sensitivity gain of up to 19% was demonstrated in comparison to the COG algorithm for the selected operation parameters. Energy resolution and image quality were on a similar level for both algorithms. Additionally, the authors demonstrated that the performance of the ML

High-resolution SPECT for small-animal imaging

International Nuclear Information System (INIS)

Qi Yujin

2006-01-01

This article presents a brief overview of the development of high-resolution SPECT for small-animal imaging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pinhole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection efficiency. (authors)

Drug-induced lung disease: High-resolution CT and histological findings

International Nuclear Information System (INIS)

Cleverley, Joanne R.; Screaton, Nicholas J.; Hiorns, Melanie P.; Flint, Julia D.A.; Mueller, Nestor L.

2002-01-01

AIM: To compare the parenchymal high-resolution computed tomography (HRCT) appearances with histological findings in patients with drug-induced lung disease and to determine the prognostic value of HRCT. MATERIALS AND METHODS: Drug history, HRCT features, histological findings and outcome at 3 months in 20 patients with drug induced-lung disease were reviewed retrospectively. The HRCT images were assessed for the pattern and distribution of abnormalities and classified as most suggestive of interstitial pneumonitis/fibrosis, diffuse alveolar damage (DAD), organizing pneumonia (OP) reaction, or a hypersensitivity reaction. RESULTS: On histopathological examination there were eight cases of interstitial pneumonitis/fibrosis, five of DAD, five of OP reactions, one of hypersensitivity reaction and one of pulmonary eosinophilia. The most common abnormalities on HRCT were ground-glass opacities (n = 17), consolidation (n = 14), interlobular septal thickening (n = 15) and centrilobular nodules (n 8). HRCT interpretation and histological diagnosis were concordant in only nine (45%) of 20 patients. The pattern, distribution, and extent of HRCT abnormalities were of limited prognostic value: all eight patients with histological findings of OP, hypersensitivity reaction, or eosinophilic infiltrate improved on follow-up compared to only five of 13 patients with interstitial pneumonitis/fibrosis or DAD. CONCLUSION: In many cases of drug-induced lung injury HRCT is of limited value in determining the histological pattern and prognosis. Cleverly, J.R. et al

3D high spectral and spatial resolution imaging of ex vivo mouse brain

International Nuclear Information System (INIS)

Foxley, Sean; Karczmar, Gregory S.; Domowicz, Miriam; Schwartz, Nancy

2015-01-01

Purpose: Widely used MRI methods show brain morphology both in vivo and ex vivo at very high resolution. Many of these methods (e.g., T 2 * -weighted imaging, phase-sensitive imaging, or susceptibility-weighted imaging) are sensitive to local magnetic susceptibility gradients produced by subtle variations in tissue composition. However, the spectral resolution of commonly used methods is limited to maintain reasonable run-time combined with very high spatial resolution. Here, the authors report on data acquisition at increased spectral resolution, with 3-dimensional high spectral and spatial resolution MRI, in order to analyze subtle variations in water proton resonance frequency and lineshape that reflect local anatomy. The resulting information compliments previous studies based on T 2 * and resonance frequency. Methods: The proton free induction decay was sampled at high resolution and Fourier transformed to produce a high-resolution water spectrum for each image voxel in a 3D volume. Data were acquired using a multigradient echo pulse sequence (i.e., echo-planar spectroscopic imaging) with a spatial resolution of 50 × 50 × 70 μm 3 and spectral resolution of 3.5 Hz. Data were analyzed in the spectral domain, and images were produced from the various Fourier components of the water resonance. This allowed precise measurement of local variations in water resonance frequency and lineshape, at the expense of significantly increased run time (16–24 h). Results: High contrast T 2 * -weighted images were produced from the peak of the water resonance (peak height image), revealing a high degree of anatomical detail, specifically in the hippocampus and cerebellum. In images produced from Fourier components of the water resonance at −7.0 Hz from the peak, the contrast between deep white matter tracts and the surrounding tissue is the reverse of the contrast in water peak height images. This indicates the presence of a shoulder in the water resonance that is not

Computer-supported resolution of measurement conflicts: a case-study in materials science

NARCIS (Netherlands)

de Jong, Hidde; Mars, Nicolaas; van der Vet, P.E.

1999-01-01

Resolving conflicts between different measurements ofa property of a physical system may be a key step in a discovery process. With the emergence of large-scale databases and knowledge bases with property measurements, computer support for the task of conflict resolution has become highly desirable.

Mistic winds, a microsatellite constellation approach to high-resolution observations of the atmosphere using infrared sounding and 3d winds measurements

Science.gov (United States)

Maschhoff, K. R.; Polizotti, J. J.; Aumann, H. H.; Susskind, J.

2016-10-01

MISTiC Winds is an approach to improve short-term weather forecasting based on a miniature high resolution, wide field, thermal emission spectrometry instrument that will provide global tropospheric vertical profiles of atmospheric temperature and humidity at high (3-4 km) horizontal and vertical ( 1 km) spatial resolution. MISTiC's extraordinarily small size, payload mass of less than 15 kg, and minimal cooling requirements can be accommodated aboard a 27U-class CubeSat or an ESPA-Class micro-satellite. Low fabrication and launch costs enable a LEO sunsynchronous sounding constellation that would collectively provide frequent IR vertical profiles and vertically resolved atmospheric motion vector wind observations in the troposphere. These observations are highly complementary to present and emerging environmental observing systems, and would provide a combination of high vertical and horizontal resolution not provided by any other environmental observing system currently in operation. The spectral measurements that would be provided by MISTiC Winds are similar to those of NASA's AIRS that was built by BAE Systems and operates aboard the AQUA satellite. These new observations, when assimilated into high resolution numerical weather models, would revolutionize short-term and severe weather forecasting, save lives, and support key economic decisions in the energy, air transport, and agriculture arenas-at much lower cost than providing these observations from geostationary orbit. In addition, this observation capability would be a critical tool for the study of transport processes for water vapor, clouds, pollution, and aerosols. Key remaining technical risks are being reduced through laboratory and airborne testing under NASA's Instrument Incubator Program.

A Virtual Study of Grid Resolution on Experiments of a Highly-Resolved Turbulent Plume

Science.gov (United States)

Maisto, Pietro M. F.; Marshall, Andre W.; Gollner, Michael J.; Fire Protection Engineering Department Collaboration

2017-11-01

An accurate representation of sub-grid scale turbulent mixing is critical for modeling fire plumes and smoke transport. In this study, PLIF and PIV diagnostics are used with the saltwater modeling technique to provide highly-resolved instantaneous field measurements in unconfined turbulent plumes useful for statistical analysis, physical insight, and model validation. The effect of resolution was investigated employing a virtual interrogation window (of varying size) applied to the high-resolution field measurements. Motivated by LES low-pass filtering concepts, the high-resolution experimental data in this study can be analyzed within the interrogation windows (i.e. statistics at the sub-grid scale) and on interrogation windows (i.e. statistics at the resolved scale). A dimensionless resolution threshold (L/D*) criterion was determined to achieve converged statistics on the filtered measurements. Such a criterion was then used to establish the relative importance between large and small-scale turbulence phenomena while investigating specific scales for the turbulent flow. First order data sets start to collapse at a resolution of 0.3D*, while for second and higher order statistical moments the interrogation window size drops down to 0.2D*.

Recent research on nuclear reaction using high-energy proton and neutron

Energy Technology Data Exchange (ETDEWEB)

Shibata, Tokushi [Tokyo Univ., Tanashi (Japan). Inst. for Nuclear Study

1997-11-01

The presently available high-energy neutron beam facilities are introduced. Then some interesting research on nuclear reaction using high-energy protons are reported such as the intermediate mass fragments emission and neutron spectrum measurements on various targets. As the important research using high-energy neutron, the (p,n) reactions on Mn, Fe, and Ni, the elastic scattering of neutrons, and the shielding experiments are discussed. (author)

UDECON: deconvolution optimization software for restoring high-resolution records from pass-through paleomagnetic measurements

Science.gov (United States)

Xuan, Chuang; Oda, Hirokuni

2015-11-01

The rapid accumulation of continuous paleomagnetic and rock magnetic records acquired from pass-through measurements on superconducting rock magnetometers (SRM) has greatly contributed to our understanding of the paleomagnetic field and paleo-environment. Pass-through measurements are inevitably smoothed and altered by the convolution effect of SRM sensor response, and deconvolution is needed to restore high-resolution paleomagnetic and environmental signals. Although various deconvolution algorithms have been developed, the lack of easy-to-use software has hindered the practical application of deconvolution. Here, we present standalone graphical software UDECON as a convenient tool to perform optimized deconvolution for pass-through paleomagnetic measurements using the algorithm recently developed by Oda and Xuan (Geochem Geophys Geosyst 15:3907-3924, 2014). With the preparation of a format file, UDECON can directly read pass-through paleomagnetic measurement files collected at different laboratories. After the SRM sensor response is determined and loaded to the software, optimized deconvolution can be conducted using two different approaches (i.e., "Grid search" and "Simplex method") with adjustable initial values or ranges for smoothness, corrections of sample length, and shifts in measurement position. UDECON provides a suite of tools to view conveniently and check various types of original measurement and deconvolution data. Multiple steps of measurement and/or deconvolution data can be compared simultaneously to check the consistency and to guide further deconvolution optimization. Deconvolved data together with the loaded original measurement and SRM sensor response data can be saved and reloaded for further treatment in UDECON. Users can also export the optimized deconvolution data to a text file for analysis in other software.

Resolution of a High Performance Cavity Beam Position Monitor System

International Nuclear Information System (INIS)

Walston, S.; Chung, C.; Fitsos, P.; Gronberg, J.; Ross, M.; Khainovski, O.; Kolomensky, Y.; Loscutoff, P.; Slater, M.; Thomson, M.; Ward, D.; Boogert, S.; Vogel, V.; Meller, R.; Lyapin, A.; Malton, S.; Miller, D.; Frisch, J.; Hinton, S.; May, J.; McCormick, D.; Smith, S.; Smith, T.; White, G.; Orimoto, T.; Hayano, H.; Honda, Y.; Terunuma, N.; Urakawa, J.

2005-01-01

International Linear Collider (ILC) interaction region beam sizes and component position stability requirements will be as small as a few nanometers. It is important to the ILC design effort to demonstrate that these tolerances can be achieved - ideally using beam-based stability measurements. It has been estimated that RF cavity beam position monitors (BPMs) could provide position measurement resolutions of less than one nanometer and could form the basis of the desired beam-based stability measurement. We have developed a high resolution RF cavity BPM system. A triplet of these BPMs has been installed in the extraction line of the KEK Accelerator Test Facility (ATF) for testing with its ultra-low emittance beam. A metrology system for the three BPMs was recently installed. This system employed optical encoders to measure each BPM's position and orientation relative to a zero-coefficient of thermal expansion carbon fiber frame and has demonstrated that the three BPMs behave as a rigid-body to less than 5 nm. To date, we have demonstrated a BPM resolution of less than 20 nm over a dynamic range of +/- 20 microns

European Collaboration for High-Resolution Measurements of Neutron Cross Sections between 1 MeV and 250 MeV

CERN Multimedia

Leal, L C; Kitis, G; Guber, K H; Yuasa nakagawa, K; Koehler, P E; Quaranta, A

2002-01-01

The experimental determination of neutron cross section data has always been of primary importance in Nuclear Physics. Many of the salient features of nuclear levels and densities can be determined from the resonant structure of such cross sections and of their decay scheme. An associated importance of precise neutron induced reaction cross sections has resulted from the worldwide interest in Accelerator Driven Systems (ADS) that has emerged at CERN and elsewhere. Many applications, such as accelerator-based transmutation of nuclear waste, energy amplification medical research, astrophysical applications and also fusion research require nuclear data that quantitatively and qualitatively go beyond the presently available traditional evaluation.\\\\ \\\\We consider a spallation driven TOF facility at the CERN-PS with an unprecedented neutron flux (1000 times the existing ones) in the broad energy range between 1 eV and 250 MeV and with very high energy resolution. The present concept for an intense neutron source m...

Analysis of twenty five impurities in uranium matrix by ICP-MS with iron measurement optimized by using reaction collision cell, cold plasma or medium resolution.

Science.gov (United States)

Quemet, Alexandre; Brennetot, Rene; Chevalier, Emilie; Prian, Edwina; Laridon, Anne-Laure; Mariet, Clarisse; Fichet, Pascal; Laszak, Ivan; Goutelard, Florence

2012-09-15

An analytical procedure was developed to determine the concentration of 25 impurities (Li, Be, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, Ag, Cd, In, Sm, Eu, Gd, Dy, W, Pb, Bi and Th) in a uranium matrix using the quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS). The dissolution of U(3)O(8) powder was made with a mixture of hydrochloric acid and nitric acid. Then, a selective separation of uranium using the UTEVA column was used before measurement by Q-ICP-MS. The procedure developed was verified using the Certified Reference Material "Morille". The analytical results agree well except for 5 elements where values are underestimated (Li, Be, In, Pb and Bi). Among the list of impurities, iron was particularly investigated because it is well known that this element possesses a polyatomic interference that increases the detection limit. A comparison between iron detection limits obtained with different methods was performed. Iron polyatomic interference was at least reduced, or at best entirely resolved in some cases, by using the cold plasma or the collision/reaction cell with several gases (He, NH(3) and CH(4)). High-resolution ICP-MS was used to compare the results obtained. A detection limit as low as 8 ng L(-1) was achieved. Copyright © 2012 Elsevier B.V. All rights reserved.

Planning exercise for the resolution of high level waste tank safety issues

International Nuclear Information System (INIS)

Bunting, J.; Saveland, J.

1992-01-01

Several conditions have been found to exist within high level radioactive waste storage tanks at the Hanford site which could lead to uncontrolled exothermic reactions and/or to the release of tank contents into the environment. These conditions have led to the establishment of four priority 1 safety issues for the Hanford tanks. Resolution of these safety issues will require the coordinated efforts of professionals in chemical, nuclear, operations, safety, and other technical areas. A coordinated and integrated approach is necessary in order to achieve resolution in the shortest possible time, while ensuring that the steps taken do not complicate the later jobs of vitrification and ultimate disposal. This paper describes the purpose, process, and results of an effort to develop a suggested approach. (author)

High resolution time integration for SN radiation transport

International Nuclear Information System (INIS)

Thoreson, Greg; McClarren, Ryan G.; Chang, Jae H.

2009-01-01

First-order, second-order, and high resolution time discretization schemes are implemented and studied for the discrete ordinates (S N ) equations. The high resolution method employs a rate of convergence better than first-order, but also suppresses artificial oscillations introduced by second-order schemes in hyperbolic partial differential equations. The high resolution method achieves these properties by nonlinearly adapting the time stencil to use a first-order method in regions where oscillations could be created. We employ a quasi-linear solution scheme to solve the nonlinear equations that arise from the high resolution method. All three methods were compared for accuracy and convergence rates. For non-absorbing problems, both second-order and high resolution converged to the same solution as the first-order with better convergence rates. High resolution is more accurate than first-order and matches or exceeds the second-order method

TH-CD-201-09: High Spatial Resolution Absorbed Dose to Water Measurements Using Optical Calorimetry in Megavoltage External Beam Therapy

Energy Technology Data Exchange (ETDEWEB)

Flores-Martinez, E; DeWerd, L [School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI (United States); Radtke, J [University of Wisconsin, Madison, WI (United States)

2016-06-15

Purpose: To develop and implement a high spatial resolution calorimeter methodology to measure absorbed dose to water (ADW) using phase shifts (PSs) of light passing through a water phantom and to compare measurements with theoretical calculations. Methods: Radiation-induced temperature changes were measured using the PSs of a He-Ne laser beam passing through a (10×10×10) cm{sup 3} water phantom. PSs were measured using a Michelson interferometer and recording the time-dependent fringe patterns on a CCD camera. The phantom was positioned at the center of the radiation field. A Varian 21EX was used to deliver 500 MU from a 9 MeV beam using a (6×6) cm{sup 2} cone. A 127cm SSD was used and the PSs were measured at depths ranging from of 1.90cm to 2.10cm in steps of 0.05cm by taking profiles at the corresponding rows across the image. PSs were computed by taking the difference between pre- and post-irradiation image frames and then measuring the amplitude of the resulting image profiles. An amplitude-to-PS calibration curve was generated using a piezoelectric transducer to mechanically induce PSs between 0.05 and 1.50 radians in steps of 0.05 radians. The temperature dependence of the refractive index of water at 632.8nm was used to convert PSs to ADW. Measured results were compared with ADW values calculated using the linac output calibration and commissioning data. Results: Milli-radian resolution in PS measurement was achieved using the described methodology. Measured radiation-induced PSs ranged from 0.10 ± 0.01 to 0.12 ± 0.01 radians at the investigated depths. After converting PSs to ADW, measured and calculated ADW values agreed within the measurement uncertainty. Conclusion: This work shows that interferometer-based calorimetry measurements are capable of achieving sub-millimeter resolution measuring 2D temperature/dose distributions, which are particularly useful for characterizing beams from modalities such as SRS, proton therapy, or microbeams.

Self consistently calibrated photopyroelectric calorimeter for the high resolution simultaneous absolute measurement of the specific heat and of the thermal conductivity

Directory of Open Access Journals (Sweden)

U. Zammit

2012-03-01

Full Text Available High temperature resolution study of the specific heat and of the thermal conductivity over the smecticA-nematic and nematic-isotropic phase transitions in octylcynobephenyl liquid crystal using a new photopyroelectric calorimetry configuration are reported, where, unlike previously adopted ones, no calibration is required other than the procedure used during the actual measurement. This makes photopyroelectric calorimetry suitable for “absolute” measurements of the thermal parameters like most other existing conventional calorimetric techniques where, however, the thermal conductivity cannot be measured.

Performance of a high resolution cavity beam position monitor system

Science.gov (United States)

Walston, Sean; Boogert, Stewart; Chung, Carl; Fitsos, Pete; Frisch, Joe; Gronberg, Jeff; Hayano, Hitoshi; Honda, Yosuke; Kolomensky, Yury; Lyapin, Alexey; Malton, Stephen; May, Justin; McCormick, Douglas; Meller, Robert; Miller, David; Orimoto, Toyoko; Ross, Marc; Slater, Mark; Smith, Steve; Smith, Tonee; Terunuma, Nobuhiro; Thomson, Mark; Urakawa, Junji; Vogel, Vladimir; Ward, David; White, Glen

2007-07-01

It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than 1 nm. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 μrad over a dynamic range of approximately ±20 μm.

High tracking resolution detectors. Final Technical Report

International Nuclear Information System (INIS)

Vasile, Stefan; Li, Zheng

2010-01-01

High-resolution tracking detectors based on Active Pixel Sensor (APS) have been valuable tools in Nuclear Physics and High-Energy Physics research, and have contributed to major discoveries. Their integration time, radiation length and readout rate is a limiting factor for the planed luminosity upgrades in nuclear and high-energy physics collider-based experiments. The goal of this program was to demonstrate and develop high-gain, high-resolution tracking detector arrays with faster readout, and shorter radiation length than APS arrays. These arrays may operate as direct charged particle detectors or as readouts of high resolution scintillating fiber arrays. During this program, we developed in CMOS large, high-resolution pixel sensor arrays with integrated readout, and reset at pixel level. Their intrinsic gain, high immunity to surface and moisture damage, will allow operating these detectors with minimal packaging/passivation requirements and will result in radiation length superior to APS. In Phase I, we designed and fabricated arrays with calorimetric output capable of sub-pixel resolution and sub-microsecond readout rate. The technical effort was dedicated to detector and readout structure development, performance verification, as well as to radiation damage and damage annealing.

High resolution muon computed tomography at neutrino beam facilities

International Nuclear Information System (INIS)

Suerfu, B.; Tully, C.G.

2016-01-01

X-ray computed tomography (CT) has an indispensable role in constructing 3D images of objects made from light materials. However, limited by absorption coefficients, X-rays cannot deeply penetrate materials such as copper and lead. Here we show via simulation that muon beams can provide high resolution tomographic images of dense objects and of structures within the interior of dense objects. The effects of resolution broadening from multiple scattering diminish with increasing muon momentum. As the momentum of the muon increases, the contrast of the image goes down and therefore requires higher resolution in the muon spectrometer to resolve the image. The variance of the measured muon momentum reaches a minimum and then increases with increasing muon momentum. The impact of the increase in variance is to require a higher integrated muon flux to reduce fluctuations. The flux requirements and level of contrast needed for high resolution muon computed tomography are well matched to the muons produced in the pion decay pipe at a neutrino beam facility and what can be achieved for momentum resolution in a muon spectrometer. Such an imaging system can be applied in archaeology, art history, engineering, material identification and whenever there is a need to image inside a transportable object constructed of dense materials

Accelerated high-resolution photoacoustic tomography via compressed sensing

Science.gov (United States)

Arridge, Simon; Beard, Paul; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

2016-12-01

Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining model-based, variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: first, we describe and model two general spatial sub-sampling schemes. Then, we discuss how to implement them using the FP interferometer and demonstrate the potential of these novel compressed sensing PAT devices through simulated data from a realistic numerical phantom and through measured data from a dynamic experimental phantom as well as from in vivo experiments. Our results show that images with good spatial resolution and contrast can be obtained from highly sub-sampled PAT data if variational image reconstruction techniques that describe the tissues structures with suitable sparsity-constraints are used. In particular, we examine the use of total variation (TV) regularization enhanced by Bregman iterations. These novel reconstruction strategies offer new opportunities to dramatically increase the acquisition speed of photoacoustic scanners that employ point-by-point sequential scanning as well as reducing the channel count of parallelized schemes that use detector arrays.

Ultra high resolution tomography

Energy Technology Data Exchange (ETDEWEB)

Haddad, W.S.

1994-11-15

Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

Crossed Optical Fiber Sensor Arrays for High-Spatial-Resolution Sensing: Application to Dissolved Oxygen Concentration Measurements

Directory of Open Access Journals (Sweden)

M. Veronica Rigo

2012-01-01

Full Text Available Optical fiber sensors using luminescent probes located along an optical fiber in the cladding of this fiber are of great interest for monitoring physical and chemical properties in their environment. The interrogation of a luminophore with a short laser pulse propagating through the fiber core allows for the measurement of the location of these luminophores. To increase the spatial resolution of such a measurements and to measure multiple analytes and properties in a confined space, a crossed optical fiber sensing platform can be employed. Here we describe the application of this platform to measuring the concentration of dissolved oxygen. The sensor is based on luminescence quenching of a ruthenium complex immobilized in a highly crosslinked film and covalently attached to the optical fibers. Both luminescence-intensity and luminescence-lifetime changes of the sensor molecules in response to changes in the concentration of oxygen dissolved in water are reported. For luminescence-intensity measurements, a second adjacent sensor region is employed as reference to account for laser pulse energy fluctuations. Enhanced quenching response in water is demonstrated by the use of organically modified poly(ethylene glycol precursors, which increase the hydrophobicity of the film surface.

A high resolution β-detector

International Nuclear Information System (INIS)

Charon, Y.; Cuzon, J.C.; Tricoire, H.; Valentin, L.

1987-01-01

We present a detector which associates a charge coupled device to a light amplifier. This image sensor must detect weak β-activity, with a 10 μm resolution and should replace the autoradiographic films used for molecular hybridization. The best results are obtained with the 35 S emittor, for which the resolution and the efficiency are respectively 20 μm and 100% (relative to the measured standard source)

Measurement of Dynamic Urethral Pressures with a High Resolution Manometry System in Continent and Incontinent Women

Science.gov (United States)

Kirby, Anna C; Tan-Kim, Jasmine; Nager, Charles W.

2015-01-01

Objectives Female stress urinary incontinence (SUI) is caused by urethral dysfunction during dynamic conditions, but current technology has limitations in measuring urethral pressures under dynamic conditions. An 8-French high resolution manometry catheter (HRM) currently in clinical use in gastroenterology may accurately measure urethral pressures under dynamic conditions because it has a 25ms response rate and circumferential pressure sensors along the length of the catheter (ManoScan® ESO, Given Imaging). We evaluated the concordance, repeatability, and tolerability of this catheter. Methods We measured resting, cough, and strain maximum urethral closure pressures (MUCPs) using HRM and measured resting MUCPs with water perfusion side-hole catheter urethral pressure profilometry (UPP) in 37 continent and 28 stress incontinent subjects. Maneuvers were repeated after moving the HRM catheter along the urethral length to evaluate whether results depend on catheter positioning. Visual analog pain scores evaluated the comfort of HRM compared to UPP. Results The correlation coefficient for resting MUCPs measured by HRM vs. UPP was high (r = 0.79, prest, cough, and strain with HRM: r= 0.92, 0.89, and 0.89. Mean MUCPs (rest, cough, strain) were higher in continent than incontinent subjects (all p continent subjects during cough and strain maneuvers compared to rest. Conclusions This preliminary study shows that HRM is concordant with standard technology, repeatable, and well tolerated in the urethra. Incontinent women have more impairment of their urethral closure pressures during cough and strain than continent women. PMID:25185595

Measurement of dynamic urethral pressures with a high-resolution manometry system in continent and incontinent women.

Science.gov (United States)

Kirby, Anna C; Tan-Kim, Jasmine; Nager, Charles W

2015-01-01

Female stress urinary incontinence is caused by urethral dysfunction during dynamic conditions, but current technology has limitations in measuring urethral pressures under these conditions. An 8-French high-resolution manometry (HRM) catheter currently in clinical use in gastroenterology may accurately measure urethral pressures under dynamic conditions because it has a 25-millisecond response rate and circumferential pressure sensors along the length of the catheter (ManoScan ESO; Given Imaging, Yoqneam, Israel). We evaluated the concordance, repeatability, and tolerability of this catheter. We measured resting, cough, and strain maximum urethral closure pressures (MUCPs) using HRM and measured resting MUCPs with water-perfusion side-hole catheter urethral pressure profilometry (UPP) in 37 continent and 28 stress-incontinent subjects. Maneuvers were repeated after moving the HRM catheter along the urethral length to evaluate whether results depend on catheter positioning. Visual analog pain scores evaluated the comfort of HRM compared to UPP. The correlation coefficient for resting MUCPs measured by HRM versus UPP was high (r = 0.79, P rest, cough, and strain with HRM: r = 0.92, 0.89, and 0.89. Mean MUCPs (rest, cough, and strain) were higher in continent than in incontinent subjects (all P continent subjects during cough and strain maneuvers compared to rest. This preliminary study shows that HRM is concordant with standard technology, repeatable, and well tolerated in the urethra. Incontinent women have more impairment of their urethral closure pressures during cough and strain than continent women.

High-resolution lattice-spacing comparator using SR

International Nuclear Information System (INIS)

Zhang, Xiaowei; Sugiyama, Hiroshi; Ando, Masami

2004-01-01

A novel lattice spacing measurement using a high-resolution self-reference d-spacing comparator has been described. Self selection of monochromatic synchrotron x-rays by a monolithic double channel-cut-crystal monochromator (MDCM) comprising silicon 2,6,4 and 6,2,4 reflections may lead to a stable, highly-collimated and narrow bandwidth beam. Also if utilizing 2,6,4 and 6,2,4 Bragg planes of a silicon sample, the interval between two associated Bragg peaks for the X-rays with wavelength of 0.13438 nm can be extremely small, so that the diffraction angle can be determined with high precision and the traveling time from one peak to the other can be marvelously reduced by the order of at least three compared to the established classical methods such as the Bond method. Thus this so-called self-reference comparator method can dramatically save measurement time and provide an absolute measurement on the basis of the x-ray wavelength of the MDCM, therefore a lattice spacing measurement with uncertainty of 10 -8 , for the 1mm 2 area on a silicon crystal within measurement time of a few ten seconds and has been achieved. (author)

High-resolution hydrogen profiling in AlGaN/GaN heterostructures grown by different epitaxial methods

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Posada Flores, F; Redondo-Cubero, A; Bengoechea, A; Brana, A F; Munoz, E [Instituto de Sistemas Optoelectronicos y Microtecnologia (ISOM) and Dpto. IngenierIa Electronica (DIE), ETSI de Telecomunicacion, Universidad Politecnica de Madrid, E-28040 Madrid (Spain); Gago, R [Centro de Micro-Analisis de Materiales, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Jimenez, A [Dpto. Electronica, Escuela Politecnica Superior, Universidad de Alcala, E-28805 Alcala de Henares, Madrid (Spain); Grambole, D, E-mail: fposada@die.upm.e [Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf, PF 51019, D-01314 Dresden (Germany)

2009-03-07

Hydrogen (H) incorporation into AlGaN/GaN heterostructures used in high electron mobility transistors, grown by different methods, is studied by high-resolution depth profiling. Samples grown on sapphire and Si(1 1 1) substrates by molecular-beam epitaxy and metal-organic vapour phase epitaxy; involving H-free and H-containing precursors, were analysed to evaluate the eventual incorporation of H into the wafer. The amount of H was measured by means of nuclear reaction analysis (NRA) using the {sup 1}H({sup 15}N,{alpha}{gamma}){sup 12}C reaction up to a depth of {approx}110 nm into the heterostructures. Interestingly, the H profiles are similar in all the samples analysed, with an increasing H content towards the surface and a negligible H incorporation into the GaN layer (0.24 {+-} 0.08 at%) or at the AlGaN/GaN interface. Therefore, NRA shows that H uptake is not related to the growth process or technique employed and that H contamination may be due to external sources after growth. The eventual correlation between topographical defects on the AlGaN surface and the H concentration are also discussed.

Measurement of the ³He(e,e'p)pn Reaction at High Missing Energies and Momenta

Energy Technology Data Exchange (ETDEWEB)

Benmokhtar, Fatiha [Rutgers Univ., New Brunswick, NJ (United States)

2004-10-01

We investigate the structure of ³He through the measurement of quasielastic ³He(e,e'). The measurements use the high duty factor electron beam and the high-precision two-spectrometer system in Hall A of the Thomas Jefferson National Accelerator Facility (TJNAF). The measurements were performed in perpendicular kinematics at fixed momentum and energy transfer by the electron, |$\\vec{q}$|= 1.5 GeV/c and omega = 837 MeV, respectively. A description of the reaction in the plane wave impulse approximation is presented. The experimental equipment is described in detail. For the measurements, the kinematics of the experiment are given. The procedures to remove backgrounds and perform radiative corrections, are also discussed in detail. The detailed method of performing radiative corrections in particular is novel to this work. Finally, the resulting cross sections, distorted spectral functions, and asymmetry ATL are presented, and the physics implications are discussed. We extracted cross sections and distorted spectral functions up to high missing momentum, pm up to 1 GeV/c, and up to high missing energies, Em up to 140 MeV, the pion production threshold. The experimental data are much higher in statistics and much more extensive in kinematic coverage than any previous measurement. Theoretical predictions are in good agreement with the data, leading to the conclusion that the cross section at large missing momenta is strongly enhanced by nucleon-nucleon correlations, with additional enhancement from final-state interactions. The conventional NN correlations present in a modern three-body nuclear wave function, along with a modern reaction mechanism theory, appear sufficient to explain the data; there is no strong indication of a need to include any additional exotic physics, such as quark degrees of freedom.

High-resolution spectroscopy diagnostics for measuring impurity ion temperature and velocity on the COMPASS tokamak

Energy Technology Data Exchange (ETDEWEB)

Weinzettl, Vladimir, E-mail: vwei@ipp.cas.cz [Institute of Plasma Physics ASCR, Prague (Czech Republic); Shukla, Gaurav [Institute of Plasma Physics ASCR, Prague (Czech Republic); Department of Applied Physics, Ghent University, Ghent (Belgium); Faculty of Mathematics and Physics, Charles University in Prague, Prague (Czech Republic); Ghosh, Joydeep [Institute for Plasma Research, Bhat, Gandhinagar (India); Melich, Radek; Panek, Radomir [Institute of Plasma Physics ASCR, Prague (Czech Republic); Tomes, Matej; Imrisek, Martin; Naydenkova, Diana [Institute of Plasma Physics ASCR, Prague (Czech Republic); Faculty of Mathematics and Physics, Charles University in Prague, Prague (Czech Republic); Varju, Josef [Institute of Plasma Physics ASCR, Prague (Czech Republic); Pereira, Tiago [Instituto de Plasmas e Fusão Nuclear, Lisboa (Portugal); Instituto Superior Técnico, Universidade de Lisboa, Lisboa (Portugal); Gomes, Rui [Instituto de Plasmas e Fusão Nuclear, Lisboa (Portugal); Abramovic, Ivana; Jaspers, Roger [Eindhoven University of Technology, Eindhoven (Netherlands); Pisarik, Michael [SQS Vlaknova optika a.s., Nova Paka (Czech Republic); Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague (Czech Republic); Odstrcil, Tomas [Max-Planck-Institut fur Plasmaphysik, Garching (Germany); Van Oost, Guido [Department of Applied Physics, Ghent University, Ghent (Belgium)

2015-10-15

Highlights: • We built a new diagnostic of poloidal plasma rotation on the COMPASS tokamak. • Improvements in throughput via toroidal integration and fiber optimizations shown. • Poloidal rotation and ion temperature measured in L- and H-mode and during RMP. • Design and parameters of a new CXRS diagnostic for COMPASS are introduced. - Abstract: High-resolution spectroscopy is a powerful tool for the measurement of plasma rotation as well as ion temperature using the Doppler shift of the emitted spectral lines and their Doppler broadening, respectively. Both passive and active diagnostic variants for the COMPASS tokamak are introduced. The passive diagnostic focused on the C III lines at about 465 nm is utilized for the observation of the poloidal plasma rotation. The current set-up of the measuring system is described, including the intended high-throughput optics upgrade. Different options to increase the fiber collection area are mentioned, including a flower-like fiber bundle, and the use of micro-lenses or tapered fibers. Recent measurements of poloidal plasma rotation of the order of 0–6 km/s are shown. The design of the new active diagnostic using a deuterium heating beam and based on charge exchange recombination spectroscopy (C VI line at 529 nm) is introduced. The tool will provide both space (0.5–5 cm) and time (10 ms) resolved toroidal plasma rotation and ion temperature profiles. The results of the Simulation of Spectra code used to examine the feasibility of charge exchange measurements on COMPASS are shown and connected with a selection of the spectrometer coupled with the CCD camera.

High-resolution spectroscopy diagnostics for measuring impurity ion temperature and velocity on the COMPASS tokamak

International Nuclear Information System (INIS)

Weinzettl, Vladimir; Shukla, Gaurav; Ghosh, Joydeep; Melich, Radek; Panek, Radomir; Tomes, Matej; Imrisek, Martin; Naydenkova, Diana; Varju, Josef; Pereira, Tiago; Gomes, Rui; Abramovic, Ivana; Jaspers, Roger; Pisarik, Michael; Odstrcil, Tomas; Van Oost, Guido

2015-01-01

Highlights: • We built a new diagnostic of poloidal plasma rotation on the COMPASS tokamak. • Improvements in throughput via toroidal integration and fiber optimizations shown. • Poloidal rotation and ion temperature measured in L- and H-mode and during RMP. • Design and parameters of a new CXRS diagnostic for COMPASS are introduced. - Abstract: High-resolution spectroscopy is a powerful tool for the measurement of plasma rotation as well as ion temperature using the Doppler shift of the emitted spectral lines and their Doppler broadening, respectively. Both passive and active diagnostic variants for the COMPASS tokamak are introduced. The passive diagnostic focused on the C III lines at about 465 nm is utilized for the observation of the poloidal plasma rotation. The current set-up of the measuring system is described, including the intended high-throughput optics upgrade. Different options to increase the fiber collection area are mentioned, including a flower-like fiber bundle, and the use of micro-lenses or tapered fibers. Recent measurements of poloidal plasma rotation of the order of 0–6 km/s are shown. The design of the new active diagnostic using a deuterium heating beam and based on charge exchange recombination spectroscopy (C VI line at 529 nm) is introduced. The tool will provide both space (0.5–5 cm) and time (10 ms) resolved toroidal plasma rotation and ion temperature profiles. The results of the Simulation of Spectra code used to examine the feasibility of charge exchange measurements on COMPASS are shown and connected with a selection of the spectrometer coupled with the CCD camera.

Measuring true localization accuracy in super resolution microscopy with DNA-origami nanostructures

International Nuclear Information System (INIS)

Reuss, Matthias; Blom, Hans; Brismar, Hjalmar; Fördős, Ferenc; Högberg, Björn; Öktem, Ozan

2017-01-01

A common method to assess the performance of (super resolution) microscopes is to use the localization precision of emitters as an estimate for the achieved resolution. Naturally, this is widely used in super resolution methods based on single molecule stochastic switching. This concept suffers from the fact that it is hard to calibrate measures against a real sample (a phantom), because true absolute positions of emitters are almost always unknown. For this reason, resolution estimates are potentially biased in an image since one is blind to true position accuracy, i.e. deviation in position measurement from true positions. We have solved this issue by imaging nanorods fabricated with DNA-origami. The nanorods used are designed to have emitters attached at each end in a well-defined and highly conserved distance. These structures are widely used to gauge localization precision. Here, we additionally determined the true achievable localization accuracy and compared this figure of merit to localization precision values for two common super resolution microscope methods STED and STORM. (paper)

High resolution and simultaneous monitoring of airborne radionuclides

International Nuclear Information System (INIS)

Abe, T.; Yamaguchi, Y.; Muguntha Manikandan, N.; Komura, K.

2005-01-01

By using 11 extremely low background Ge detectors at Ogoya Underground Laboratory, it became possible to investigate temporal variations of airborne 212 Pb (T 1/2 =10.6 h) along with 210 Pb and 7 Be with order of magnitude higher time resolution. Then, we have measured airborne nuclides at three monitoring points, (1) roof of our laboratory (LLRL; 40 m ASL), (2) Shinshiku Plateau (640 m ASL) located about 8 km from LLRL as a comparison of vertical distribution, and (3) Hegura Island (10 m ASL) at about 50 km from Wajima located north of Noto Peninsula facing on the Sea of Japan (about 180 km to the north-northeast of LLRL), to investigate influence of Asian continent. Airborne nuclides were collected by high volume air samplers at intervals of a few hours at either two or three points simultaneously. In the same manner, high resolution monitoring was carried out also at the time of passage of typhoon and cold front. In this study, we observed drastic temporal variations of airborne radionuclides and correlations of multiple monitoring points. The results indicate that high resolution and simultaneous monitoring is very useful to understand dynamic state of variations of airborne nuclides due to short and long-term air-mass movement. (author)

Absolute high-resolution Se+ photoionization cross-section measurements with Rydberg-series analysis

International Nuclear Information System (INIS)

Esteves, D. A.; Bilodeau, R. C.; Sterling, N. C.; Phaneuf, R. A.; Kilcoyne, A. L. D.; Red, E. C.; Aguilar, A.

2011-01-01

Absolute single photoionization cross-section measurements for Se + ions were performed at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory using the photo-ion merged-beams technique. Measurements were made at a photon energy resolution of 5.5 meV from 17.75 to 21.85 eV spanning the 4s 2 4p 3 4 S 3/2 o ground-state ionization threshold and the 2 P 3/2 o , 2 P 1/2 o , 2 D 5/2 o , and 2 D 3/2 o metastable state thresholds. Extensive analysis of the complex resonant structure in this region identified numerous Rydberg series of resonances and obtained the Se 2+ 4s 2 4p 23 P 2 and 4s 2 4p 21 S 0 state energies. In addition, particular attention was given to removing significant effects in the measurements due to a small percentage of higher-order undulator radiation.

Decay Time Measurement for Different Energy Depositions of Plastic Scintillator Fabricated by High Temperature Polymerization Reaction

Energy Technology Data Exchange (ETDEWEB)

Lee, Cheol Ho; Son, Jaebum; Lee, Sangmin; Kim, Tae Hoon; Kim, Yong-Kyun [Hanyang University, Seoul (Korea, Republic of)

2016-10-15

Plastic scintillators are based on organic fluorite. They have many advantages such as fast rise and decay time, high optical transmission, ease of manufacturing, low cost, and large available size. For these reasons they are widely used for particle identification. Also, protection of people against a variety of threats (such as nuclear, radiological, and explosive) represents a true challenge along with the continuing development of science and technology. The plastic scintillator is widely used in various devise, which serves for nuclear, photonics, quantum, and high-energy physics. The plastic scintillator is probably the most widely used organic detector, and polystyrene is one of the most widely used materials in the making of the plastic scintillator detector. Thus, a styrene monomer as a solvent was used to fabricate the plastic scintillator by using high temperature polymerization reaction, and then the emission wavelength and the decay times for different energy depositions were measured by using the fabricated plastic scintillator. A plastic scintillator was fabricated to measure decay time for different energy depositions using the high temperature polymerization. Emission wavelength was measured of 426.05 nm to confirm a scintillator property using the spectrophotometer. Four gamma-ray sources (Cs-137, Co-60, Na-22, and Ba-133) were used to evaluate effect for decay time of different energy depositions. The average decay time of the fabricated plastic scintillator was measured to approximately 4.72 ns slightly higher more than commercial plastic scintillator. In future, light output and linearity will be measured to evaluate other property compared with the commercial scintillator.

Decay Time Measurement for Different Energy Depositions of Plastic Scintillator Fabricated by High Temperature Polymerization Reaction

International Nuclear Information System (INIS)

Lee, Cheol Ho; Son, Jaebum; Lee, Sangmin; Kim, Tae Hoon; Kim, Yong-Kyun

2016-01-01

Plastic scintillators are based on organic fluorite. They have many advantages such as fast rise and decay time, high optical transmission, ease of manufacturing, low cost, and large available size. For these reasons they are widely used for particle identification. Also, protection of people against a variety of threats (such as nuclear, radiological, and explosive) represents a true challenge along with the continuing development of science and technology. The plastic scintillator is widely used in various devise, which serves for nuclear, photonics, quantum, and high-energy physics. The plastic scintillator is probably the most widely used organic detector, and polystyrene is one of the most widely used materials in the making of the plastic scintillator detector. Thus, a styrene monomer as a solvent was used to fabricate the plastic scintillator by using high temperature polymerization reaction, and then the emission wavelength and the decay times for different energy depositions were measured by using the fabricated plastic scintillator. A plastic scintillator was fabricated to measure decay time for different energy depositions using the high temperature polymerization. Emission wavelength was measured of 426.05 nm to confirm a scintillator property using the spectrophotometer. Four gamma-ray sources (Cs-137, Co-60, Na-22, and Ba-133) were used to evaluate effect for decay time of different energy depositions. The average decay time of the fabricated plastic scintillator was measured to approximately 4.72 ns slightly higher more than commercial plastic scintillator. In future, light output and linearity will be measured to evaluate other property compared with the commercial scintillator

Evaluation and optimization of the High Resolution Research Tomograph (HRRT)

International Nuclear Information System (INIS)

Knoess, C.

2004-01-01

Positron Emission Tomography (PET) is an imaging technique used in medicine to determine qualitative and quantitative metabolic parameters in vivo. The High Resolution Research Tomograph (HRRT) is a new high resolution tomograph that was designed for brain studies (312 mm transaxial field-of-view (FOV), 252 mm axial FOV). The detector blocks are arranged in a quadrant sharing design and consist of two crystal layers with dimensions of 2.1 mm x 2.1 mm x 7.5 mm. The main detector material is the newly developed scintillator lutetium oxyorthosilicate (LSO). Events from the different crystal layers are distinguished by Pulse Shape Discrimination (PSD) to gain Depth of Interaction (DOI) information. This will improve the spatial resolution, especially at the edges of the FOV. A prototype of the tomograph was installed at the Max-Planck Institute for Neurological Research in Cologne, Germany in 1999 and was evaluated with respect to spatial resolution, sensitivity, scatter fraction, and count rate behavior. These performance measurements showed that this prototype provided a spatial resolution of around 2.5 mm in a volume big enough to contain the human brain. A comparison with a single layer HRRT prototype showed a 10% worsening of the resolution, despite the fact that DOI was used. Without DOI, the resolution decreased considerably. The sensitivity, as measured with a 22 Na point source, was 46.5 cps/kBq for an energy window of 350-650 keV and 37.9 cps/kBq for an energy window of 400-650 keV, while the scatter fractions were 56% for 350-650 keV and 51% for 400-650 keV, respectively. A daily quality check was developed and implemented that uses the uniform, natural radioactive background of the scintillator material LSO. In 2001, the manufacturer decided to build a series of additional HRRT scanners to try to improve the design (detector electronics, transmission source design, and shielding against out-of-FOV activity) and to eliminate problems (difficult detector

A fragmentation study of kaempferol using electrospray quadrupole time-of-flight mass spectrometry at high mass resolution

Science.gov (United States)

March, Raymond E.; Miao, Xiu-Sheng

2004-02-01

A mass spectrometric method based on the combined use of electrospray ionization, collision-induced dissociation and tandem mass spectrometry at high mass resolution has been applied to an investigation of the structural characterization of protonated and deprotonated kaempferol (3,5,7,4'-tetrahydroxyflavone). Low-energy product ion mass spectra of [M+H]+ ions showed simple fragmentations of the C ring that permitted characterization of the substituents in the A and B rings. In addition, four rearrangement reactions accompanied by losses of C2H2O, CHO[radical sign], CO, and H2O were observed. Low-energy product ion mass spectra of [M-H]- ions showed only four rearrangement reactions accompanied by losses of OH[radical sign], CO, CH2O, and C2H2O. The use of elevated cone voltages permitted observation of product ion mass spectra of selected primary and secondary fragment ions so that each fragment ion reported was observed as a direct product of its immediate precursor ion. Product ion mass spectra examined at high mass resolution allowed unambiguous determination of the elemental composition of fragment ions and resolution of two pairs of isobars. Fragmentation mechanisms and ion structures have been proposed.

Reaction mechanism in high energy heavy-ion collisions

International Nuclear Information System (INIS)

Tanihata, Isao.

1982-04-01

The reaction mechanism in high energy heavy-ion collision is discussed. The discussion is mainly based on the experimental data. Empirical equations have been given for the total cross-sections of nucleus-nucleus reactions and the reaction cross-sections. These cross-sections are well described by the geometrical size of the colliding nuclei. The cross-sections are also understood by microscopic calculation. The charged particle multiplicity gives additional information about the geometrical aspect of heavy ion collision. The data suggested that the total energy, independent of projectile size, is most important for determining the multiplicity. The inclusive proton spectrum in a heavy ion collision showed two distinct regions. The one is the fragment region, and the other the participant region. The spectral shapes of inclusive pion spectra are reasonably well explained by the Coulomb interaction of pions with nuclear fragments. The high energy heavy ion reaction occurs in the overlap region of the projectile and target. This has been tested by measuring the number of participants for various reactions. The space and the time structure of the collision are also discussed in this paper as well as the dynamical aspects of the collision. (Kato, T.)

A new PET detector concept for compact preclinical high-resolution hybrid MR-PET

Science.gov (United States)

Berneking, Arne; Gola, Alberto; Ferri, Alessandro; Finster, Felix; Rucatti, Daniele; Paternoster, Giovanni; Jon Shah, N.; Piemonte, Claudio; Lerche, Christoph

2018-04-01

This work presents a new PET detector concept for compact preclinical hybrid MR-PET. The detector concept is based on Linearly-Graded SiPM produced with current FBK RGB-HD technology. One 7.75 mm x 7.75 mm large sensor chip is coupled with optical grease to a black coated 8 mm x 8 mm large and 3 mm thick monolithic LYSO crystal. The readout is obtained from four readout channels with the linear encoding based on integrated resistors and the Center of Gravity approach. To characterize the new detector concept, the spatial and energy resolutions were measured. Therefore, the measurement setup was prepared to radiate a collimated beam to 25 different points perpendicular to the monolithic scintillator crystal. Starting in the center point of the crystal at 0 mm / 0 mm and sampling a grid with a pitch of 1.75 mm, all significant points of the detector were covered by the collimator beam. The measured intrinsic spatial resolution (FWHM) was 0.74 +/- 0.01 mm in x- and 0.69 +/- 0.01 mm in the y-direction at the center of the detector. At the same point, the measured energy resolution (FWHM) was 13.01 +/- 0.05 %. The mean intrinsic spatial resolution (FWHM) over the whole detector was 0.80 +/- 0.28 mm in x- and 0.72 +/- 0.19 mm in y-direction. The energy resolution (FWHM) of the detector was between 13 and 17.3 % with an average energy resolution of 15.7 +/- 1.0 %. Due to the reduced thickness, the sensitivity of this gamma detector is low but still higher than pixelated designs with the same thickness due to the monolithic crystals. Combining compact design, high spatial resolution, and high sensitivity, the detector concept is particularly suitable for applications where the scanner bore size is limited and high resolution is required - as is the case in small animal hybrid MR-PET.

High energy resolution and first time-dependent positron annihilation induced Auger electron spectroscopty

Energy Technology Data Exchange (ETDEWEB)

Mayer, Jakob

2010-04-03

It was the aim of this thesis to improve the existing positron annihilation induced Auger spectrometer at the highly intense positron source NEPOMUC (NEutron induced POsitron source MUniCh) in several ways: Firstly, the measurement time for a single spectrum should be reduced from typically 12 h to roughly 1 h or even less. Secondly, the energy resolution, which amounted to {delta}E/E{approx}10%, should be increased by at least one order of magnitude in order to make high resolution positron annihilation induced Auger spectroscopy (PAES)-measurements of Auger transitions possible and thus deliver more information about the nature of the Auger process. In order to achieve these objectives, the PAES spectrometer was equipped with a new electron energy analyzer. For its ideal operation all other components of the Auger analysis chamber had to be adapted. Particularly the sample manipulation and the positron beam guidance had to be renewed. Simulations with SIMION {sup registered} ensured the optimal positron lens parameters. After the adjustment of the new analyzer and its components, first measurements illustrated the improved performance of the PAES setup: Firstly, the measurement time for short overview measurements was reduced from 3 h to 420 s. The measurement time for more detailed Auger spectra was shortened from 12 h to 80 min. Secondly, even with the reduced measurement time, the signal to noise ratio was also enhanced by one order of magnitude. Finally, the energy resolution was improved to {delta}E/E < 1. The exceptional surface sensitivity and elemental selectivity of PAES was demonstrated in measurements of Pd and Fe, both coated with Cu layers of varying thickness. PAES showed that with 0.96 monolayer of Cu on Fe, more than 55% of the detected Auger electrons stem from Cu. In the case of the Cu coated Pd sample 0.96 monolayer of Cu resulted in a Cu Auger fraction of more than 30% with PAES and less than 5% with electron induced Auger spectroscopy

High resolution kilometric range optical telemetry in air by radio frequency phase measurement

Energy Technology Data Exchange (ETDEWEB)

Guillory, Joffray; García-Márquez, Jorge; Truong, Daniel; Wallerand, Jean-Pierre [Laboratoire Commun de Métrologie LNE-Cnam (LCM), LNE, 1 rue Gaston Boissier, 75015 Paris (France); Šmíd, Radek [Laboratoire Commun de Métrologie LNE-Cnam (LCM), LNE, 1 rue Gaston Boissier, 75015 Paris (France); Institute of Scientific Instruments of the CAS, Kralovopolska 147, 612 64 Brno (Czech Republic); Alexandre, Christophe [Centre d’Études et de Recherche en Informatique et Communications (CEDRIC), Cnam, 292 rue St-Martin, 75003 Paris (France)

2016-07-15

We have developed an optical Absolute Distance Meter (ADM) based on the measurement of the phase accumulated by a Radio Frequency wave during its propagation in the air by a laser beam. In this article, the ADM principle will be described and the main results will be presented. In particular, we will emphasize how the choice of an appropriate photodetector can significantly improve the telemeter performances by minimizing the amplitude to phase conversion. Our prototype, tested in the field, has proven its efficiency with a resolution better than 15 μm for a measurement time of 10 ms and distances up to 1.2 km.

A high resolution portable spectroscopy system

International Nuclear Information System (INIS)

Kulkarni, C.P.; Vaidya, P.P.; Paulson, M.; Bhatnagar, P.V.; Pande, S.S.; Padmini, S.

2003-01-01

Full text: This paper describes the system details of a High Resolution Portable Spectroscopy System (HRPSS) developed at Electronics Division, BARC. The system can be used for laboratory class, high-resolution nuclear spectroscopy applications. The HRPSS consists of a specially designed compact NIM bin, with built-in power supplies, accommodating a low power, high resolution MCA, and on-board embedded computer for spectrum building and communication. A NIM based spectroscopy amplifier and a HV module for detector bias are integrated (plug-in) in the bin. The system communicates with a host PC via a serial link. Along-with a laptop PC, and a portable HP-Ge detector, the HRPSS offers a laboratory class performance for portable applications

ASIC for time-of-flight measurements with picosecond timing resolution

Energy Technology Data Exchange (ETDEWEB)

Stankova, Vera; Shen, Wei; Harion, Tobias [Kirchhoff-Institute for Physics, Heidelberg Univ. (Germany)

2015-07-01

The Positron Emission Tomography (PET) images are especially affected by a high level of noise. This noise affects the potential to detect and discriminate the tumor in relation to the background. Including Time-of-Flight information, with picosecond time resolution, within the conventional PET scanners will improve the signal-to-noise ratio (SNR) and in sequence the quality of the medical images. A mix-mode ASIC (STIC3) has been developed for high precision timing measurements with Silicon Photomultipliers (SiPM). The STiC3 is 64-channel chip, with fully differential analog front-end for crosstalk and electronic noise immunity. It integrates Time to Digital Converters (TDC) with time binning of 50.2 ps for time and energy measurements. Measurements of the of the analog front-end show a time jitter less than 20 ps and jitter of the TDC together with the digital part is around 37 ps. Further the timing of a channel has been tested by injecting a pulse into two channels and measuring the time difference of the recorded timestamps. A Coincidence Time Resolution (CTR) of 215 ps FWHM has been obtained with 3.1 x 3.1 x 15 mm{sup 2} LYSO:Ce scintillator crystals and Hamamatsu SiPM matric (S12643-050CN(x)). Characterization measurements with the chip and its performances are presented.

High resolution measurements of solar induced chlorophyll fluorescence in the Fraunhofer oxigen bands

Science.gov (United States)

Mazzoni, M.; Agati, G.; Cecchi, G.; Toci, G.; Mazzinghi, P.

2017-11-01

Spectra of solar radiance reflected by leaves close to the Fraunhofer bands show the net contribution of chlorophyll fluorescence emission which adds to the reflected solar spectra. In a laboratory experiment, a low stray light, high resolution, 0.85 m double monochromator was used to filter radiation living leaves still attached to the plant in correspondence of the 687 nm and 760 nm O2 absorption bands. Reference spectra from a non fluorescent white reference were also acquired. Acquisition was performed by a Microchannel plate (MCP) intensified diode array with 512 elements. A fit of the spectral data outside the absorption lines allowed to retrieve the spectral base-line as a function of wavelength for the reference panel and the leaf. Reflectance functions were determined extending the Plascyck equation system to all the resolved lines of the oxygen absorption bands and using the base-lines for the continuum values. Fluorescence was deduced from the same equation system, using both the measured leaf and reference radiance spectra and the leaf reflectance fitting function.

Functional high-resolution computed tomography of pulmonary vascular and airway reactions. Experimental results. Funktionelle HR-CT der Lunge. Experimentelle Untersuchungen pulmonaler Gefaess- und Atemwegsreaktionen

Energy Technology Data Exchange (ETDEWEB)

Herold, C.J. (Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria) Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Radiology); Brown, R.H. (Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Radiology Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Anesthesiology and Intensive Care Medicine Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Physiology); Wetzel, R.C.; Herold, S.M. (Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Anesthesiology and Intensive Care Medicine); Zeerhouni, E.A. (Johns Hopkins Medical Institutions, Baltimore, MD (United States). Dept. of Radiology)

1993-03-01

We describe the use of high-resolution computed tomography (HRCT) for assessment of the function of pulmonary vessels and airways. With its excellent spatial resolution, HRCT is able to demonstrate pulmonary structures as small as 300 [mu]m and can be used to monitor changes following various stimuli. HRCT also provides information about structures smaller than 300 [mu]m through measurement of parenchymal background density. To date, sequential, spiral and ultrafast HRCT techniques have been used in a variety of challenges to gather information about the anatomical correlates of traditional physiological measurements, thus making anatomical-physiological correlation possible. HRCT of bronchial reactivity can demonstrate the location and time course of aerosol-induced broncho-constriction and may show changes not apparent on spirometry. HRCT of the pulmonary vascular system visualized adaptations of vessels during hypoxia and intravascular volume loading and elucidates cardiorespiratory interactions. Experimental studies provide a basis for potential clinical applications of this method. (orig.).

3D high spectral and spatial resolution imaging of ex vivo mouse brain

Energy Technology Data Exchange (ETDEWEB)

Foxley, Sean, E-mail: sean.foxley@ndcn.ox.ac.uk; Karczmar, Gregory S. [Department of Radiology, University of Chicago, Chicago, Illinois 60637 (United States); Domowicz, Miriam [Department of Pediatrics, University of Chicago, Chicago, Illinois 60637 (United States); Schwartz, Nancy [Department of Pediatrics, Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois 60637 (United States)

2015-03-15

Purpose: Widely used MRI methods show brain morphology both in vivo and ex vivo at very high resolution. Many of these methods (e.g., T{sub 2}{sup *}-weighted imaging, phase-sensitive imaging, or susceptibility-weighted imaging) are sensitive to local magnetic susceptibility gradients produced by subtle variations in tissue composition. However, the spectral resolution of commonly used methods is limited to maintain reasonable run-time combined with very high spatial resolution. Here, the authors report on data acquisition at increased spectral resolution, with 3-dimensional high spectral and spatial resolution MRI, in order to analyze subtle variations in water proton resonance frequency and lineshape that reflect local anatomy. The resulting information compliments previous studies based on T{sub 2}{sup *} and resonance frequency. Methods: The proton free induction decay was sampled at high resolution and Fourier transformed to produce a high-resolution water spectrum for each image voxel in a 3D volume. Data were acquired using a multigradient echo pulse sequence (i.e., echo-planar spectroscopic imaging) with a spatial resolution of 50 × 50 × 70 μm{sup 3} and spectral resolution of 3.5 Hz. Data were analyzed in the spectral domain, and images were produced from the various Fourier components of the water resonance. This allowed precise measurement of local variations in water resonance frequency and lineshape, at the expense of significantly increased run time (16–24 h). Results: High contrast T{sub 2}{sup *}-weighted images were produced from the peak of the water resonance (peak height image), revealing a high degree of anatomical detail, specifically in the hippocampus and cerebellum. In images produced from Fourier components of the water resonance at −7.0 Hz from the peak, the contrast between deep white matter tracts and the surrounding tissue is the reverse of the contrast in water peak height images. This indicates the presence of a shoulder in

High-efficient method for spectrometric data real time processing with increased resolution of a measuring channel

International Nuclear Information System (INIS)

Ashkinaze, S.I.; Voronov, V.A.; Nechaev, Yu.I.

1988-01-01

Solution of reduction problem as a mean to increase spectrometric tract resolution when it is realized using the digit-by-digit modified method and special strategy, significantly reducing the time of processing, is considered. The results presented confirm that the complex measurement tract plus microcomputer is equivalent to the use of the tract with a higher resolution, and the use of the digit-by-digit modified method permits to process spectrometric information in real time scale

First measurement of the 34S(p ,γ )35Cl reaction rate through indirect methods for presolar nova grains

Science.gov (United States)

Gillespie, S. A.; Parikh, A.; Barton, C. J.; Faestermann, T.; José, J.; Hertenberger, R.; Wirth, H.-F.; de Séréville, N.; Riley, J. E.; Williams, M.

2017-08-01

Sulphur isotopic ratio measurements may help to establish the astrophysical sites in which certain presolar grains were formed. Nova model predictions of the 34S/32S ratio are, however, unreliable due to the lack of an experimental 34S(p ,γ )35Cl reaction rate. To this end, we have measured the 34S(3He,d )35Cl reaction at 20 MeV using a high resolution quadrupole-dipole-dipole-dipole magnetic spectrograph. Twenty-two levels over 6.2 MeV rate has been determined using a Monte Carlo method. Hydrodynamic nova model calculations have been performed using this new reaction rate. These models show that remaining uncertainties in the 34S(p ,γ ) rate affect nucleosynthesis predictions by less than a factor of 1.4, and predict a 34S/32S isotopic ratio of 0.014-0.017. Since recent type II supernova models predict 34S/32S=0.026 -0.053 , the 34S/32S isotopic ratio may be used, in conjunction with other isotopic signatures, to distinguish presolar grains from oxygen-neon nova and type II supernova origin. Our results address a key nuclear physics uncertainty on which recent considerations discounting the nova origin of several grains depend.

High-resolution CT of airway reactivity

International Nuclear Information System (INIS)

Herold, C.J.; Brown, R.H.; Hirshman, C.A.; Mitzner, W.; Zerhouni, E.A.

1990-01-01

Assessment of airway reactivity has generally been limited to experimental nonimaging models. This authors of this paper used high-resolution CT (HRCT) to evaluate airway reactivity and to calculate airway resistance (Raw) compared with lung resistance (RL). Ten anesthetized and ventilated dogs were investigated with HRCT (10 contiguous 2-mm sections through the lower lung lobes) during control state, following aerosol histamine challenge, and following posthistamine hyperinflation. The HRCT scans were digitized, and areas of 10 airways per dog (diameter, 1-10 mm) were measured with a computer edging process. Changes in airway area and Raw (calculated by 1/[area] 2 ) were measured. RL was assessed separately, following the same protocol. Data were analyzed by use of a paired t-test with significance at p < .05

DEVELOPMENT OF A HIGH RATE HIGH RESOLUTION DETECTOR FOR EXAFS EXPERIMENTS.

Energy Technology Data Exchange (ETDEWEB)

DE GERONIMO,G.; O CONNOR,P.; BEUTTENMULLER,R.H.; LI,Z.; KUCZEWSKI,A.J.; SIDDONS,D.P.

2002-11-10

A new detector for EXAFS experiments is being developed. It is based on a multi-element Si sensor and dedicated readout ASICs. The sensor is composed of 384 pixels, each having 1 mm{sup 2} area, arranged in four quadrants of 12 x 8 elements, and wire-bonded to 32-channel front-end ASICs. Each channel implements low noise preamplification with self-adaptive continuous reset, high order shaper, band-gap referenced baseline stabilizer, one threshold comparator and two DAC adjustable window comparators, each followed by a 24-bit counter. Fabricated in 0.35{micro}m CMOS dissipates about 8mW per channel. First measurements show at room temperature a resolution of 14 rms electrons without the detector and of 40 rms electrons (340eV) with the detector connected and biased. Cooling at -35C a FWHM of 205eV (167eV from electronics) was measured at the Mn-K{alpha} line. A resolution of about 300eV was measured for rates approaching 100kcps/cm{sup 2} per channel, corresponding to an overall rate in excess of 10MHz/cm{sup 2}. A channel-to-channel threshold dispersion after DACs adjustment of 2.5 rms electrons was also measured.

High Resolution Elevation Contours

Data.gov (United States)

Minnesota Department of Natural Resources — This dataset contains contours generated from high resolution data sources such as LiDAR. Generally speaking this data is 2 foot or less contour interval.

First high-statistics and high-resolution recoil-ion data from the WITCH retardation spectrometer

Science.gov (United States)

Finlay, P.; Breitenfeldt, M.; Porobić, T.; Wursten, E.; Ban, G.; Beck, M.; Couratin, C.; Fabian, X.; Fléchard, X.; Friedag, P.; Glück, F.; Herlert, A.; Knecht, A.; Kozlov, V. Y.; Liénard, E.; Soti, G.; Tandecki, M.; Traykov, E.; Van Gorp, S.; Weinheimer, Ch.; Zákoucký, D.; Severijns, N.

2016-07-01

The first high-statistics and high-resolution data set for the integrated recoil-ion energy spectrum following the β^+ decay of 35Ar has been collected with the WITCH retardation spectrometer located at CERN-ISOLDE. Over 25 million recoil-ion events were recorded on a large-area multichannel plate (MCP) detector with a time-stamp precision of 2ns and position resolution of 0.1mm due to the newly upgraded data acquisition based on the LPC Caen FASTER protocol. The number of recoil ions was measured for more than 15 different settings of the retardation potential, complemented by dedicated background and half-life measurements. Previously unidentified systematic effects, including an energy-dependent efficiency of the main MCP and a radiation-induced time-dependent background, have been identified and incorporated into the analysis. However, further understanding and treatment of the radiation-induced background requires additional dedicated measurements and remains the current limiting factor in extracting a beta-neutrino angular correlation coefficient for 35Ar decay using the WITCH spectrometer.

Extension of least squares spectral resolution algorithm to high-resolution lipidomics data

Energy Technology Data Exchange (ETDEWEB)

Zeng, Ying-Xu [Department of Chemistry, University of Bergen, PO Box 7803, N-5020 Bergen (Norway); Mjøs, Svein Are, E-mail: svein.mjos@kj.uib.no [Department of Chemistry, University of Bergen, PO Box 7803, N-5020 Bergen (Norway); David, Fabrice P.A. [Bioinformatics and Biostatistics Core Facility, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL) and Swiss Institute of Bioinformatics (SIB), Lausanne (Switzerland); Schmid, Adrien W. [Proteomics Core Facility, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne (Switzerland)

2016-03-31

Lipidomics, which focuses on the global study of molecular lipids in biological systems, has been driven tremendously by technical advances in mass spectrometry (MS) instrumentation, particularly high-resolution MS. This requires powerful computational tools that handle the high-throughput lipidomics data analysis. To address this issue, a novel computational tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. The algorithm features the customized generation of a lipid compound library and mass spectral library, which covers the major lipid classes such as glycerolipids, glycerophospholipids and sphingolipids. Next, the algorithm performs least squares resolution of spectra and chromatograms based on the theoretical isotope distribution of molecular ions, which enables automated identification and quantification of molecular lipid species. Currently, this methodology supports analysis of both high and low resolution MS as well as liquid chromatography-MS (LC-MS) lipidomics data. The flexibility of the methodology allows it to be expanded to support more lipid classes and more data interpretation functions, making it a promising tool in lipidomic data analysis. - Highlights: • A flexible strategy for analyzing MS and LC-MS data of lipid molecules is proposed. • Isotope distribution spectra of theoretically possible compounds were generated. • High resolution MS and LC-MS data were resolved by least squares spectral resolution. • The method proposed compounds that are likely to occur in the analyzed samples. • The proposed compounds matched results from manual interpretation of fragment spectra.

Extension of least squares spectral resolution algorithm to high-resolution lipidomics data

International Nuclear Information System (INIS)

Zeng, Ying-Xu; Mjøs, Svein Are; David, Fabrice P.A.; Schmid, Adrien W.

2016-01-01

Lipidomics, which focuses on the global study of molecular lipids in biological systems, has been driven tremendously by technical advances in mass spectrometry (MS) instrumentation, particularly high-resolution MS. This requires powerful computational tools that handle the high-throughput lipidomics data analysis. To address this issue, a novel computational tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. The algorithm features the customized generation of a lipid compound library and mass spectral library, which covers the major lipid classes such as glycerolipids, glycerophospholipids and sphingolipids. Next, the algorithm performs least squares resolution of spectra and chromatograms based on the theoretical isotope distribution of molecular ions, which enables automated identification and quantification of molecular lipid species. Currently, this methodology supports analysis of both high and low resolution MS as well as liquid chromatography-MS (LC-MS) lipidomics data. The flexibility of the methodology allows it to be expanded to support more lipid classes and more data interpretation functions, making it a promising tool in lipidomic data analysis. - Highlights: • A flexible strategy for analyzing MS and LC-MS data of lipid molecules is proposed. • Isotope distribution spectra of theoretically possible compounds were generated. • High resolution MS and LC-MS data were resolved by least squares spectral resolution. • The method proposed compounds that are likely to occur in the analyzed samples. • The proposed compounds matched results from manual interpretation of fragment spectra.

Characterisation of PM2.5 concentrations and turbulent fluxes on a island of the Venice lagoon using high temporal resolution measurements

Energy Technology Data Exchange (ETDEWEB)

Donateo, A.; Contini, D.; Cesari, D. [CNR-ISAC, Istituto di Scienze dell' Atmosfera e del Clima, Lecce (Italy); Belosi, F.; Santachiara, G.; Prodi, F. [CNR-ISAC, Istituto di Scienze dell' Atmosfera e del Clima, Bologna (Italy); Gambaro, A. [Venice Univ. (Italy). Environmental Sciences Dept.

2012-08-15

This work presents an analysis of PM2.5 concentrations and vertical turbulent fluxes on an island of the Venice lagoon. Data were collected during three measurement campaigns in spring, summer and winter periods. Measurements were taken with a high-resolution optical PM2.5 detector, coupled with a micrometeorological station that allowed the evaluation of the vertical turbulent fluxes of PM2.5 using the eddy-correlation technique. The main objective of this paper is to analyse the daily and seasonal pattern in PM2.5 concentrations and fluxes and to discuss their correlation with the main meteorological and micrometeorological parameters using high temporal resolution measurements. Observed data showed a seasonal pattern in turbulent fluxes with daytime average positive value during winter and negative during summer. Deposition velocities, ranged from -60 to 20 mm/s, appeared to be mainly influenced by atmospheric stability. There were larger emissions in cases of high wind velocities blowing from water sector indicating a significant potential contribution of sea spray to PM2.5 fluxes. The local atmospheric circulation, due to the orography of the area, was characterised by diurnal winds coming from the Adriatic Sea and nocturnal wind coming from the Alps. This circulation influenced deposition velocity creating an increase of negative fluxes in the morning at the starting of the sea breeze. A diurnal pattern in concentration has been observed and it is similar for all three measurement campaigns, with higher concentrations in nocturnal periods. The daily pattern was investigated in terms of its correlation with meteorological and micro-meteorological parameters, and was found highly correlated with the diurnal pattern of boundary layer height (BLH) and with relative humidity. (orig.)

Aircraft micro-doppler feature extraction from high range resolution profiles

CSIR Research Space (South Africa)

Berndt, RJ

2015-10-01

Full Text Available The use of high range resolution measurements and the micro-Doppler effect produced by rotating or vibrating parts of a target has been well documented. This paper presents a technique for extracting features related to helicopter rotors...

Ultra-high resolution coded wavefront sensor

KAUST Repository

Wang, Congli

2017-06-08

Wavefront sensors and more general phase retrieval methods have recently attracted a lot of attention in a host of application domains, ranging from astronomy to scientific imaging and microscopy. In this paper, we introduce a new class of sensor, the Coded Wavefront Sensor, which provides high spatio-temporal resolution using a simple masked sensor under white light illumination. Specifically, we demonstrate megapixel spatial resolution and phase accuracy better than 0.1 wavelengths at reconstruction rates of 50 Hz or more, thus opening up many new applications from high-resolution adaptive optics to real-time phase retrieval in microscopy.

High resolution microphotonic needle for endoscopic imaging (Conference Presentation)

Science.gov (United States)

Tadayon, Mohammad Amin; Mohanty, Aseema; Roberts, Samantha P.; Barbosa, Felippe; Lipson, Michal

2017-02-01

GRIN (Graded index) lens have revolutionized micro endoscopy enabling deep tissue imaging with high resolution. The challenges of traditional GRIN lenses are their large size (when compared with the field of view) and their limited resolution. This is because of the relatively weak NA in standard graded index lenses. Here we introduce a novel micro-needle platform for endoscopy with much higher resolution than traditional GRIN lenses and a FOV that corresponds to the whole cross section of the needle. The platform is based on polymeric (SU-8) waveguide integrated with a microlens micro fabricated on a silicon substrate using a unique molding process. Due to the high index of refraction of the material the NA of the needle is much higher than traditional GRIN lenses. We tested the probe in a fluorescent dye solution (19.6 µM Alexa Flour 647 solution) and measured a numerical aperture of 0.25, focal length of about 175 µm and minimal spot size of about 1.6 µm. We show that the platform can image a sample with the field of view corresponding to the cross sectional area of the waveguide (80x100 µm2). The waveguide size can in principle be modified to vary size of the imaging field of view. This demonstration, combined with our previous work demonstrating our ability to implant the high NA needle in a live animal, shows that the proposed system can be used for deep tissue imaging with very high resolution and high field of view.

Direct comparison of high-temporal-resolution CINE MRI with Doppler ultrasound for assessment of diastolic dysfunction in mice.

Science.gov (United States)

Roberts, Thomas A; Price, Anthony N; Jackson, Laurence H; Taylor, Valerie; David, Anna L; Lythgoe, Mark F; Stuckey, Daniel J

2017-10-01

Diastolic dysfunction is a sensitive early indicator of heart failure and can provide additional data to conventional measures of systolic function. Transmitral Doppler ultrasound, which measures the one-dimensional flow of blood through the mitral valve, is currently the preferred method for the measurement of diastolic function, but the measurement of the left ventricular volume changes using high-temporal-resolution cinematic magnetic resonance imaging (CINE MRI) is an alternative approach which is emerging as a potentially more robust and user-independent technique. Here, we investigated the performance of high-temporal-resolution CINE MRI and compared it with ultrasound for the detection of diastolic dysfunction in a mouse model of myocardial infarction. An in-house, high-temporal-resolution, retrospectively gated CINE sequence was developed with a temporal resolution of 1 ms. Diastolic function in mice was assessed using a custom-made, open-source reconstruction package. Early (E) and late (A) left ventricular filling phases were easily identifiable, and these measurements were compared directly with high-frequency, pulsed-wave, Doppler ultrasound measurements of mitral valve inflow. A repeatability study established that high-temporal-resolution CINE MRI and Doppler ultrasound showed comparable accuracy when measuring E/A in normal control mice. However, when applied in a mouse model of myocardial infarction, high-temporal-resolution CINE MRI indicated diastolic heart failure (E/A = 0.94 ± 0.11), whereas ultrasound falsely detected normal cardiac function (E/A = 1.21 ± 0.11). The addition of high-temporal-resolution CINE MRI to preclinical imaging studies enhances the library of sequences available to cardiac researchers and potentially identifies diastolic heart failure early in disease progression. © 2017 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.

Studies of fission fragment yields via high-resolution γ-ray spectroscopy

Science.gov (United States)

Wilson, J. N.; Lebois, M.; Qi, L.; Amador-Celdran, P.; Bleuel, D.; Briz, J. A.; Carroll, R.; Catford, W.; Witte, H. De; Doherty, D. T.; Eloirdi, R.; Georgiev, G.; Gottardo, A.; Goasduff, A.; Hadyñska-Klek, K.; Hauschild, K.; Hess, H.; Ingeberg, V.; Konstantinopoulos, T.; Ljungvall, J.; Lopez-Martens, A.; Lorusso, G.; Lozeva, R.; Lutter, R.; Marini, P.; Matea, I.; Materna, T.; Mathieu, L.; Oberstedt, A.; Oberstedt, S.; Panebianco, S.; Podolyak, Zs.; Porta, A.; Regan, P. H.; Reiter, P.; Rezynkina, K.; Rose, S. J.; Sahin, E.; Seidlitz, M.; Serot, O.; Shearman, R.; Siebeck, B.; Siem, S.; Smith, A. G.; Tveten, G. M.; Verney, D.; Warr, N.; Zeiser, F.; Zielinska, M.

2018-03-01

Precise spectroscopic information on the fast neutron induced fission of the 238U(n,f) reaction was recently gained using a new technique which involved coupling of the Miniball high resolution y-ray spectrometer and the LICORNE directional neutron source. The experiment allowed measurement of the isotopic fission yields for around 40 even-even nuclei at an incident neutron energy of around 2 MeV where yield data are very sparse. In addition spectroscopic information on very neutron-rich fission products was obtained. Results were compared to models, both the JEFF-3.1.1 data base and the GEF code, and large discrepancies for the S1 fission mode in the Sn/Mo isotope pair were discovered. This suggests that current models are overestimating the role played by spherical shell effects in fast neutron induced fission. In late 2017 and 2018 the nu-ball hybrid spectrometer will be constructed at the IPN Orsay to perform further experimental investigations with directional neutrons coupled to a powerful hybrid Ge/LaBr3 detector array. This will open up new possibilities for measurements of fission yields for fast-neutron-induced fission using the spectroscopic technique and will be complimentary to other methods being developed.

Studies of fission fragment yields via high-resolution γ-ray spectroscopy

Directory of Open Access Journals (Sweden)

Wilson J.N.

2018-01-01

Full Text Available Precise spectroscopic information on the fast neutron induced fission of the 238U(n,f reaction was recently gained using a new technique which involved coupling of the Miniball high resolution y-ray spectrometer and the LICORNE directional neutron source. The experiment allowed measurement of the isotopic fission yields for around 40 even-even nuclei at an incident neutron energy of around 2 MeV where yield data are very sparse. In addition spectroscopic information on very neutron-rich fission products was obtained. Results were compared to models, both the JEFF-3.1.1 data base and the GEF code, and large discrepancies for the S1 fission mode in the Sn/Mo isotope pair were discovered. This suggests that current models are overestimating the role played by spherical shell effects in fast neutron induced fission. In late 2017 and 2018 the nu-ball hybrid spectrometer will be constructed at the IPN Orsay to perform further experimental investigations with directional neutrons coupled to a powerful hybrid Ge/LaBr3 detector array. This will open up new possibilities for measurements of fission yields for fast-neutron-induced fission using the spectroscopic technique and will be complimentary to other methods being developed.

Breaking New Ground with High Resolution Turn-By-Turn BPMs at the ESRF

CERN Document Server

Farvacque, L; Scheidt, K

2001-01-01

This High-Resolution, Turn-by-Turn BPM system is a low-cost extension to the existing BPM system, based on the RF-multiplexing concept, used for slow Closed-Orbit measurements. With this extension Beam Position measurements in both planes, at all (224) BPMs in the 844 m ESRF Storage Ring, for up to 2048 Orbit Turns with 1 μm resolution are performed. The data acquisition is synchronised to a single, flat 1 μs, transverse deflection kick to the 1μs beamfill in the 2.8μs revolution period. The high quality of this synchronisation, together with the good reproducibility of the deflection kick and the overall stability of the Closed Orbit beam allows to repeat the kick and acquisition in many cycles. The subsequent averaging of the data obtained in these cycles yields the 1um resolution. The latter allows lattice measurements with high precision such as the localisation of very small focussing errors and modulation in Beta values and phase advances. It also finds an unique ...

High resolution deformation measurements at active volcanoes: a new remote sensing technology

Science.gov (United States)

Hort, M. K.; Scharff, L.; Gerst, A.; Meier, K.; Falk, S.; Peters, G.; Ripepe, M.

2013-12-01

It is known from observations at different volcanoes using ULP seismic observations that the volcanic edifice deforms slightly prior to an eruption. It can be expected that immediately prior to an eruption the largest deformation should occur in the vicinity of the vent. However, placing instruments at the vent is impossible as they will be destroyed during an eruption. Here we present new, high temporal resolution (up to 300Hz) deformation measurement that utilizes the phase information of a frequency modulated Doppler radar system. We decompose the Doppler signal into two parts, one part which allows us to measure speeds significantly above 0.5m/s (i.e. the movement of volcanic ash and clasts). The other part utilizes the slow phase changes of the signal reflected from non-moving objects, i.e. the volcanic edifice. This signal is used to measure very slow and longer term deformations, which are the main subject of this study. The method has been tested measuring the displacement of high rise buildings during strong winds. It can be shown that displacements down to 50 μm can be resolved without a problem. We apply this method to different data sets collected at Stromboli volcano, Italy, as well as Santiaguito volcano, Guatemala. At Stromboli we observed the NE crater once in 2008 and once in 2011. During both campaigns we observe on average a displacement between 1 and 5mm before different eruptions. This displacement can be interpreted as a widening of the conduit prior to an eruption. In a couple of cases even an oscillatory movement is observed with frequencies of about 0.5Hz. Finite element modeling of the rise of a pressurized slug indicates that deformations at the crater rim on the order of a 1mm or less are certainly reasonable. In the case of Santiaguito volcano prior to an eruption we observe a pre eruptive displacement 5-15mm and after the end of an eruption a displacement of up to 1m before the next eruption occurs. This can be interpreted as in