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Sample records for irradiated one-sided dual-column

  1. Explosive Bolt Dual-Initiated from One Side

    NASA Technical Reports Server (NTRS)

    Snow, Eric

    2011-01-01

    An explosive bolt has been developed that has a one-sided dual initiation train all the way down to the pyro charge for high reliability, while still allowing the other side of the bolt to remain in place after actuation to act as a thermal seal in an extremely high-temperature environment. This lightweight separation device separates at a single fracture plane, and has as much redundancy/reliability as possible. The initiation train comes into the explosive bolt from one side.

  2. The Torsion of Box Beams with One Side Lacking

    NASA Technical Reports Server (NTRS)

    Cambilargiu, E

    1940-01-01

    The torsion of box beams of rectangular section, the edges of which are strengthened by flanges, and of which one side is lacking, is analyzed by the energy method. The torsional stresses are generally taken up by the bending of the two parallel walls, the rigidity of which is augmented by the third wall. The result was checked experimentally on duralumin and plywood boxes. The torsion recorded was 10 to 30 percent less than that given by the calculation, owing to self-stiffening.

  3. Peptide nanotube aligning side chains onto one side.

    PubMed

    Tabata, Yuki; Mitani, Shota; Kimura, Shunsaku

    2016-06-01

    A novel pseudo cyclic penta-β-peptide composed of a β-naphthylalanine, two β-alanines, and a sequence of ethylenediamine-succinic acid (CP5ES) is synthesized and investigated on peptide nanotube (PNT) formation. When the PNT is formed with the maximum number of intermolecular hydrogen bonds between the cyclic peptides, the sequence enables the alignment of the side chains, naphthyl groups, on one side of the PNT. Microscopic and spectroscopic observations of CP5ES crystals reveal that CP5ES forms rod- or needle-shaped molecular assemblies showing exciton coupling of the Cotton effect and predominant monomer emission, which are different from a reference cyclic tri-β-peptide composed of a β-naphthylalanine and two β-alanines. Insertion of a sequence of ethylenediamine-succinic acid into β-amino acids in the cyclic skeleton is therefore suggested to be effective to make the side chains aligning on one side of the PNT. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. PMID:27282135

  4. Some characteristics of probabilistic one-sided splicing systems

    NASA Astrophysics Data System (ADS)

    Selvarajoo, Mathuri; Fong, Wan Heng; Sarmin, Nor Haniza; Turaev, Sherzod

    2013-04-01

    A theoretical model for DNA computing using the recombination behavior of DNA molecules known as asplicing system has been introduced in 1987. Splicing systems are based on the splicing operation which, informally, cuts two strings at the specific places and attaches the prefix of the first string to the suffix of the second string and the prefix of the second string to the suffix of the first string yielding the new strings. It is known that splicing systems with finite sets of axioms and splicing rules only generate regular languages. Hence, different types of restrictions for splicing systems have been considered to increase the computational power of the languages generated. Recently, probabilistic splicing systems have been introduced where the probabilities are initially associated with the axioms, and the probabilities of the generated strings are computed from the probabilities of the initial strings. In this paper, some properties of probabilistic one-sided splicing systems, which are special types of probabilistic splicing systems, are investigated. We prove that probabilistic one-sided splicing systems can also increase the computational power of the languages generated.

  5. One-side riddled basin below and beyond the blowout bifurcation

    NASA Astrophysics Data System (ADS)

    Yang, H. L.

    2000-10-01

    In this Rapid Comunication we report a phenomenon of a one-side riddled basin where one side of the basin of attraction of an attractor on an invariant subspace (ISS) is globally riddled, while the other side is only locally riddled. This kind of basin appears due to the symmetry breaking with respect to the ISS. This one-side riddled basin can even persist beyond the blowout bifurcation, contrary to the previously reported riddled basins which exist only below the blowout transition. An experimental situation where this phenomenon can be expected is proposed.

  6. One-side riddled basin below and beyond the blowout bifurcation

    PubMed

    Yang

    2000-10-01

    In this Rapid Comunication we report a phenomenon of a one-side riddled basin where one side of the basin of attraction of an attractor on an invariant subspace (ISS) is globally riddled, while the other side is only locally riddled. This kind of basin appears due to the symmetry breaking with respect to the ISS. This one-side riddled basin can even persist beyond the blowout bifurcation, contrary to the previously reported riddled basins which exist only below the blowout transition. An experimental situation where this phenomenon can be expected is proposed. PMID:11089070

  7. Diagnosing the Causes and Severity of One-sided Message Contention

    SciTech Connect

    Tallent, Nathan R.; Vishnu, Abhinav; van Dam, Hubertus; Daily, Jeffrey A.; Kerbyson, Darren J.; Hoisie, Adolfy

    2015-02-11

    Two trends suggest network contention for one-sided messages is poised to become a performance problem that concerns application developers: an increased interest in one-sided programming models and a rising ratio of hardware threads to network injection bandwidth. Unfortunately, it is difficult to reason about network contention and one-sided messages because one-sided tasks can either decrease or increase contention. We present effective and portable techniques for diagnosing the causes and severity of one-sided message contention. To detect that a message is affected by contention, we maintain statistics representing instantaneous (non-local) network resource demand. Using lightweight measurement and modeling, we identify the portion of a message's latency that is due to contention and whether contention occurs at the initiator or target. We attribute these metrics to program statements in their full static and dynamic context. We characterize contention for an important computational chemistry benchmark on InfiniBand, Cray Aries, and IBM Blue Gene/Q interconnects. We pinpoint the sources of contention, estimate their severity, and show that when message delivery time deviates from an ideal model, there are other messages contending for the same network links. With a small change to the benchmark, we reduce contention up to 50% and improve total runtime as much as 20%.

  8. Supporting the Global Arrays PGAS Model Using MPI One-Sided Communication

    SciTech Connect

    Dinan, James; Balaji, Pavan; Hammond, Jeffrey R.; Krishnamoorthy, Sriram; Tipparaju, Vinod

    2012-05-21

    The industry-standard Message Passing Interface (MPI) provides one-sided communication functionality and is available on virtually every parallel computing system. However, it is believed that MPI’s one-sided model is not rich enough to support higher-level global address space parallel programming models. We present the first successful application of MPI one-sided communication as a runtime system for a PGAS model, Global Arrays (GA). This work has an immediate impact on users of GA applications, such as NWChem, who often must wait several months to a year or more before GA becomes available on a new architecture. We explore challenges present in the application of MPI-2 to PGAS models and motivate new features in the upcoming MPI-3 standard. The performance of our system is evaluated on several popular high-performance computing architectures through communication benchmarking and application benchmarking using the NWChem computational chemistry suite.

  9. [Multiresidue analysis of organophosphorus pesticides in vegetables and fruits using dual-column GC-FPD, -NPD].

    PubMed

    Ueno, E; Oshima, H; Saito, I; Matsumoto, H

    2001-12-01

    We investigated simultaneous and consecutive analytical methods for pesticide residues in large numbers of vegetable and fruit samples. Extraction of the sample with acetonitrile was followed by a salting-out step using a graduated cylinder. Co-extractives were removed by gel permeation chromatography (GPC) and the pesticide eluate was separated to 2 fractions. Firstly, the second fraction (85-125 mL) was passed through a silica-gel mini-column. After putting a Florisil mini-column before the silica-gel mini-column, the first fraction (55-85 mL) was passed through the tandem mini-columns, which were then eluted with 15 mL of 50% acetone/petroleum ether. The eluate was subjected to dual-column GC with dual FPD (P mode, column Rtx-OPPesticides) and NPD (column Rtx-200) detectors. Recoveries of 63 organophosphorus pesticides from fortified spinach, tomato, apple and strawberry, ranged from 71 to 126% with RSD values of 1-18%, except for the RSDs of omethoate, isoxathion, and pyraclofos (20% <). Detection limits of pesticides were 0.5-2 ng/g. Surveillance of pesticides in vegetables and fruits was carried out by using the present method. From 20 out of 30 samples, 15 pesticides (39 in total) were detected. The results indicated that the present method can be applied as an efficient and reliable tool for monitoring organophosphorus pesticide residues in vegetables and fruits. PMID:11875824

  10. One-Sided Nonparametric Comparison of Treatments with a Standard for Unequal Sample Sizes.

    ERIC Educational Resources Information Center

    Chakraborti, S.; Gibbons, Jean D.

    1992-01-01

    The one-sided problem of comparing treatments with a standard on the basis of data available in the context of a one-way analysis of variance is examined, and the methodology of S. Chakraborti and J. D. Gibbons (1991) is extended to the case of unequal sample sizes. (SLD)

  11. Processing and Representation of Arguments in One-Sided Texts about Disputed Topics

    ERIC Educational Resources Information Center

    Wolfe, Michael B.; Tanner, Shawna M.; Taylor, Andrew R.

    2013-01-01

    We examine students' processing and representation of arguments and counterarguments in one-sided scientific texts. In Experiment 1, students read texts about evolution and TV violence. Sentence reading times indicated that subjects slowed down reading to the extent that arguments were both more consistent, and inconsistent, with the text…

  12. Optimizing Bandwidth Limited Problems Using One-SidedCommunication and Overlap

    SciTech Connect

    Bell, Christian; Bonachea, Dan; Nishtala, Rajesh; Yelick, Katherine

    2005-10-14

    Partitioned Global Address Space languages like Unified Parallel C (UPC) are typically valued for their expressiveness, especially for computations with fine-grained random accesses. In this paper we show that the one-sided communication model used in these languages also has a significant performance advantage for bandwidth-limited applications. We demonstrate this benefit through communication microbenchmarks and a case-study that compares UPC and MPI implementations of the NAS Fourier Transform (FT) benchmark. Our optimizations rely on aggressively overlapping communication with computation but spreading communication events throughout the course of the local computation. This alleviates the potential communication bottleneck that occurs when the communication is packed into a single phase (e.g., the large all-to-all in a multidimensional FFT). Even though the new algorithms require more messages for the same total volume of data, the resulting overlap leads to speedups of over 1.75x and 1.9x for the two-sided and one-sided implementations, respectively, when compared to the default NAS Fortran/MPI release. Our best one-sided implementations show an average improvement of 15 percent over our best two-sided implementations. We attribute this difference to the lower software overhead of one-sided communication, which is partly fundamental to the semantic difference between one-sided and two-sided communication. Our UPC results use the Berkeley UPC compiler with the GASNet communication system, and demonstrate the portability and scalability of that language and implementation, with performance approaching 0.5TFlop/s on the FT benchmark running on 512 processors.

  13. Analyzing One-Sided vs. Two-Sided Subduction Arising from Mantle Convection Simulations

    NASA Astrophysics Data System (ADS)

    Kaplan, M. S.; Becker, T. W.

    2013-12-01

    Purely thermal plate tectonic generation models struggle to consistently reproduce one-sided subduction as is observed on Earth (Tackley 2000; Van Heck and Tackley 2008; Foley and Becker 2009), and instead produce two-sided subduction where the subducting slab contains a significant flux of material from both plates. The models of Crameri et al. (2012) demonstrate that the implementation of a free upper surface boundary condition and the inclusion of a weak hydrated crust can facilitate one-sided subduction. We employ a similar model configuration to Crameri et al. (2012) to further investigate the dynamics and energetics which are associated with one-sided vs. two-sided subduction. We use a 2D finite difference code based off of the algorithms of I2ELVIS (Gerya and Yuen 2007) where material parameters are tracked on Lagrangian markers and the Stokes and Energy equations are solved on a Cartesian grid. A free surface is implemented by a low viscosity and density 'sticky air layer' (Schmeling et al., 2008; Crameri et al., 2012) with the stabilization routine of Duretz et al. (2011) to prevent the 'drunken seaman' instability (Kaus et al., 2010). The effects of a weak crust, shear heating, a free surface or free slip upper mechanical boundary condition, plasticity as a function of depth or pressure, and the sticky air layer thermal conductivity on one-sided vs. two-sided subduction are investigated. When we observe one-sided subduction it is transient and can smoothly evolve back to a two-sided configuration. In our models, 'sidedness' is a spectrum, rather than either discretely one or two sided, and the models move between the two regimes throughout the model runs. We observe that the thermal conductivity of the sticky air layer can influence the dynamics of the convective domain. Elevated values of thermal conductivity compared to those of rock must be implemented in the sticky air layer in order to maintain a constant temperature at the surface of the convective

  14. Detecting faked continuous-variable entanglement using one-sided device-independent entanglement witnesses

    NASA Astrophysics Data System (ADS)

    Opanchuk, B.; Arnaud, L.; Reid, M. D.

    2014-06-01

    We demonstrate the principle of one-sided device-independent continuous-variable (CV) quantum information. In situations of no trust, we show by enactment how the use of standard CV entanglement criteria can mislead Charlie into thinking that Alice and Bob share entanglement, when the data are actually generated classically using a local-hidden-variable theory based on the Wigner function. We distinguish between criteria that demonstrate CV entanglement, and criteria that demonstrate the CV Einstein-Podolsky-Rosen (EPR) steering paradox. We show that the latter, but not the former, are necessarily one-sided device-independent entanglement witnesses, and can be used by Charlie to signify genuine EPR entanglement, if he trusts only Alice. A monogamy result for the EPR steering paradox confirms the security of the shared amplitude values in that case.

  15. One-sided infrared thermal imaging for flaw characterization of ceramic matrix composites

    SciTech Connect

    Deemer, C.; Sun, J. G.; Ellingson, W. A.

    2000-05-16

    One-sided infrared thermal imaging is being used to characterize voids and delamination in SiC/SiC composites. Flaw depth is estimated by examining the decay of surface temperature after application of a thermal pulse. Digital analysis of the surface temperature/time relationship allows characterization of the sizes and positions of defects. Results show that defects of various sizes and depths can be characterized in SiC/SiC composites with the technique.

  16. One-Sided Social Media Comments Influenced Opinions And Intentions About Home Birth: An Experimental Study.

    PubMed

    Witteman, Holly O; Fagerlin, Angela; Exe, Nicole; Trottier, Marie-Eve; Zikmund-Fisher, Brian J

    2016-04-01

    As people increasingly turn to social media to access and create health evidence, the greater availability of data and information ought to help more people make evidence-informed health decisions that align with what matters to them. However, questions remain as to whether people can be swayed in favor of or against options by polarized social media, particularly in the case of controversial topics. We created a composite mock news article about home birth from six real news articles and randomly assigned participants in an online study to view comments posted about the original six articles. We found that exposure to one-sided social media comments with one-sided opinions influenced participants' opinions of the health topic regardless of their reported level of previous knowledge, especially when comments contained personal stories. Comments representing a breadth of views did not influence opinions, which suggests that while exposure to one-sided comments may bias opinions, exposure to balanced comments may avoid such bias. PMID:27044975

  17. One-sided outflows/jets from rotating stars with complex magnetic fields

    NASA Astrophysics Data System (ADS)

    Lovelace, R. V. E.; Romanova, M. M.; Ustyugova, G. V.; Koldoba, A. V.

    2010-11-01

    We present for the first time axisymmetric magnetohydrodynamic simulations which show the formation of intrinsically asymmetric or one-sided outflows or jets from disc accretion on to a rotating star with a complex magnetic field. The intrinsic magnetic field of the star is assumed to consist of a superposition of an aligned dipole and an aligned quadrupole in different proportions. The star is assumed to be rapidly rotating in the sense that the star's magnetosphere is in the propeller regime where strong outflows occur. Our simulations show that for conditions where there is a significant quadrupole component in addition to the dipole component, then a dominantly one-sided conical wind tends to form on the side of the equatorial plane with the larger value of the intrinsic axial magnetic field at a given distance. For cases where the quadrupole component is absent or very small, we find that dominantly one-sided outflows also form, but the direction of the flow `flip-flops' between upward and downward on a time-scale of ~30d for a protostar. The average outflow will thus be symmetrical. In the case of a pure quadrupole field we find symmetric outflows in the upward and downward directions.

  18. Unveiling substrate RNA binding to H/ACA RNPs: one side fits all

    PubMed Central

    Li, Hong

    2008-01-01

    The H/ACA RNP pseudouridylases function on a large number of extraordinarily complex RNA substrates including pre-ribosomal and small nuclear RNAs. Recent structural data show that H/ACA RNPs capture their RNA substrates via a simple one-sided attachment model. However, the precise placement of each RNA substrate into the active site of the catalytic subunit relies on the essential functions of the RNP proteins. The specific roles of each HACA RNP protein are being elucidated by a combination of structural and biochemical studies. PMID:18178425

  19. The discrete one-sided Lipschitz condition for convex scalar conservation laws

    NASA Technical Reports Server (NTRS)

    Brenier, Yann; Osher, Stanley

    1986-01-01

    Physical solutions to convex scalar conservation laws satisfy a one-sided Lipschitz condition (OSLC) that enforces both the entropy condition and their variation boundedness. Consistency with this condition is therefore desirable for a numerical scheme and was proved for both the Godunov and the Lax-Friedrichs scheme--also, in a weakened version, for the Roe scheme, all of them being only first order accurate. A new, fully second order scheme is introduced here, which is consistent with the OSLC. The modified equation is considered and shows interesting features. Another second order scheme is then considered and numerical results are discussed.

  20. Analytical Derivation of the Inverse Moments of One-Sided Correlated Gram Matrices With Applications

    NASA Astrophysics Data System (ADS)

    Elkhalil, Khalil; Kammoun, Abla; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

    2016-05-01

    This paper addresses the development of analytical tools for the computation of the moments of random Gram matrices with one side correlation. Such a question is mainly driven by applications in signal processing and wireless communications wherein such matrices naturally arise. In particular, we derive closed-form expressions for the inverse moments and show that the obtained results can help approximate several performance metrics such as the average estimation error corresponding to the Best Linear Unbiased Estimator (BLUE) and the Linear Minimum Mean Square Error LMMSE or also other loss functions used to measure the accuracy of covariance matrix estimates.

  1. Experimental study of impact oscillator with one-sided elastic constraint.

    PubMed

    Ing, James; Pavlovskaia, Ekaterina; Wiercigroch, Marian; Banerjee, Soumitro

    2008-03-13

    In this paper, extensive experimental investigations of an impact oscillator with a one-sided elastic constraint are presented. Different bifurcation scenarios under varying the excitation frequency near grazing are shown for a number of values of the excitation amplitude. The mass acceleration signal is used to effectively detect contacts with the secondary spring. The most typical recorded scenario is when a non-impacting periodic orbit bifurcates into an impacting one via grazing mechanism. The resulting orbit can be stable, but in many cases it loses stability through grazing. Following such an event, the evolution of the attractor is governed by a complex interplay between smooth and non-smooth bifurcations. In some cases, the occurrence of coexisting attractors is manifested through discontinuous transition from one orbit to another through boundary crisis. The stability of non-impacting and impacting period-1 orbits is then studied using a newly proposed experimental procedure. The results are compared with the predictions obtained from standard theoretical stability analysis and a good correspondence between them is shown for different stiffness ratios. A mathematical model of a damped impact oscillator with one-sided elastic constraint is used in the theoretical studies. PMID:17947209

  2. Thermostructural Behavior of a Hypersonic Aircraft Sandwich Panel Subjected to Heating on One Side

    NASA Technical Reports Server (NTRS)

    Ko, William L.

    1997-01-01

    Thermostructural analysis was performed on a heated titanium honeycomb-core sandwich panel. The sandwich panel was supported at its four edges with spar-like substructures that acted as heat sinks, which are generally not considered in the classical analysis. One side of the panel was heated to high temperature to simulate aerodynamic heating during hypersonic flight. Two types of surface heating were considered: (1) flat-temperature profile, which ignores the effect of edge heat sinks, and (2) dome-shaped-temperature profile, which approximates the actual surface temperature distribution associated with the existence of edge heat sinks. The finite-element method was used to calculate the deformation field and thermal stress distributions in the face sheets and core of the sandwich panel. The detailed thermal stress distributions in the sandwich panel are presented, and critical stress regions are identified. The study shows how the magnitudes of those critical stresses and their locations change with different heating and edge conditions. This technical report presents comprehensive, three-dimensional graphical displays of thermal stress distributions in every part of a titanium honeycomb-core sandwich panel subjected to hypersonic heating on one side. The plots offer quick visualization of the structural response of the panel and are very useful for hot structures designers to identify the critical stress regions.

  3. Exact Power and Sample Size Calculations for the Two One-Sided Tests of Equivalence.

    PubMed

    Shieh, Gwowen

    2016-01-01

    Equivalent testing has been strongly recommended for demonstrating the comparability of treatment effects in a wide variety of research fields including medical studies. Although the essential properties of the favorable two one-sided tests of equivalence have been addressed in the literature, the associated power and sample size calculations were illustrated mainly for selecting the most appropriate approximate method. Moreover, conventional power analysis does not consider the allocation restrictions and cost issues of different sample size choices. To extend the practical usefulness of the two one-sided tests procedure, this article describes exact approaches to sample size determinations under various allocation and cost considerations. Because the presented features are not generally available in common software packages, both R and SAS computer codes are presented to implement the suggested power and sample size computations for planning equivalence studies. The exact power function of the TOST procedure is employed to compute optimal sample sizes under four design schemes allowing for different allocation and cost concerns. The proposed power and sample size methodology should be useful for medical sciences to plan equivalence studies. PMID:27598468

  4. Network-friendly one-sided communication through multinode cooperation on petascale cray xt5 systems

    SciTech Connect

    Tipparaju, Vinod; Que, Xinyu; Yu, Weikuan; Vetter, Jeffrey S

    2011-05-01

    ne-sided communication is important to enable asynchronous communication and data movement for Global Address Space (GAS) programming models. Such communication is typically realized through direct messages between initiator and target processes. For petascale systems with 10,000s of nodes and 100,000s of cores, these direct messages require dedicated communication buffers and/or channels, which can lead to significant scalability challenges for GAS programming models. In this paper, we describe a network-friendly communication model, multinode cooperation, to enable indirect one-sided communication. Compute nodes work together to handle one-sided requests through (1) request forwarding in which one node can intercept a request and forward it to a target node, and (2) request aggregation in which one node can aggregate many requests to a target node. We have implemented multinode cooperation for a popular GAS runtime library, Aggregate Remote Memory Copy Interface (ARMCI). Our experimental results on a large-scale Cray XT5 system demonstrate that, multinode cooperation is able to greatly increase the memory scalability by reducing the number of communication buffers. In addition, multinode cooperation improves the resiliency of GAS runtime system to network contention. Furthermore, multinode cooperation can benefit the performance of scientific applications. In one case, it reduces the total execution time of an NWChem application by 52%.

  5. Network-friendly one-sided communication through multinode cooperation on petascale cray xt5 systems

    SciTech Connect

    Tipparaju, Vinod; Que, Xinyu; Yu, Weikuan; Vetter, Jeffrey S

    2011-01-01

    ne-sided communication is important to enable asynchronous communication and data movement for Global Address Space (GAS) programming models. Such communication is typically realized through direct messages between initiator and target processes. For petascale systems with 10,000s of nodes and 100,000s of cores, these direct messages require dedicated communication buffers and/or channels, which can lead to significant scalability challenges for GAS programming models. In this paper, we describe a network-friendly communication model, multinode cooperation, to enable indirect one-sided communication. Compute nodes work together to handle one-sided requests through (1) request forwarding in which one node can intercept a request and forward it to a target node, and (2) request aggregation in which one node can aggregate many requests to a target node. We have implemented multinode cooperation for a popular GAS runtime library, Aggregate Remote Memory Copy Interface (ARMCI). Our experimental results on a large-scale Cray XT5 system demonstrate that, multinode cooperation is able to greatly increase the memory scalability by reducing the number of communication buffers. In addition, multinode cooperation improves the resiliency of GAS runtime system to network contention. Furthermore, multinode cooperation can benefit the performance of scientific applications. In one case, it reduces the total execution time of an NWChem application by 52%.

  6. Development of the One-Sided Nonlinear Adaptive Doppler Shift Estimation

    NASA Technical Reports Server (NTRS)

    Beyon, Jeffrey Y.; Koch, Grady J.; Singh, Upendra N.; Kavaya, Michael J.; Serror, Judith A.

    2009-01-01

    The new development of a one-sided nonlinear adaptive shift estimation technique (NADSET) is introduced. The background of the algorithm and a brief overview of NADSET are presented. The new technique is applied to the wind parameter estimates from a 2-micron wavelength coherent Doppler lidar system called VALIDAR located in NASA Langley Research Center in Virginia. The new technique enhances wind parameters such as Doppler shift and power estimates in low Signal-To-Noise-Ratio (SNR) regimes using the estimates in high SNR regimes as the algorithm scans the range bins from low to high altitude. The original NADSET utilizes the statistics in both the lower and the higher range bins to refine the wind parameter estimates in between. The results of the two different approaches of NADSET are compared.

  7. Parallel Photonic Quantum Computation Assisted by Quantum Dots in One-Side Optical Microcavities

    NASA Astrophysics Data System (ADS)

    Luo, Ming-Xing; Wang, Xiaojun

    2014-07-01

    Universal quantum logic gates are important elements for a quantum computer. In contrast to previous constructions on one degree of freedom (DOF) of quantum systems, we investigate the possibility of parallel quantum computations dependent on two DOFs of photon systems. We construct deterministic hyper-controlled-not (hyper-CNOT) gates operating on the spatial-mode and the polarization DOFs of two-photon or one-photon systems by exploring the giant optical circular birefringence induced by quantum-dot spins in one-sided optical microcavities. These hyper-CNOT gates show that the quantum states of two DOFs can be viewed as independent qubits without requiring auxiliary DOFs in theory. This result can reduce the quantum resources by half for quantum applications with large qubit systems, such as the quantum Shor algorithm.

  8. Parallel photonic quantum computation assisted by quantum dots in one-side optical microcavities.

    PubMed

    Luo, Ming-Xing; Wang, Xiaojun

    2014-01-01

    Universal quantum logic gates are important elements for a quantum computer. In contrast to previous constructions on one degree of freedom (DOF) of quantum systems, we investigate the possibility of parallel quantum computations dependent on two DOFs of photon systems. We construct deterministic hyper-controlled-not (hyper-CNOT) gates operating on the spatial-mode and the polarization DOFs of two-photon or one-photon systems by exploring the giant optical circular birefringence induced by quantum-dot spins in one-sided optical microcavities. These hyper-CNOT gates show that the quantum states of two DOFs can be viewed as independent qubits without requiring auxiliary DOFs in theory. This result can reduce the quantum resources by half for quantum applications with large qubit systems, such as the quantum Shor algorithm. PMID:25030424

  9. One-Sided Measurement Approach on Ultrasonic Beam Path Analysis in CFRP Composite Laminates

    NASA Astrophysics Data System (ADS)

    Im, K. H.; Hsu, D. K.; Kim, H. J.; Song, S. J.; Dayal, V.; Barnard, D.; Park, J. W.; Lee, K. S.; Yang, Y. J.; Yang, I. Y.

    2008-02-01

    Composite materials are attractive for a wide range of applications because of high performance engineering structures. In particular, the importance of carbon-fiber reinforced plastics (CFRP) has been generally recognized in both space and civil aircraft industries; so, CFRP composite laminates are widely used. It is very important to detect defects in composite laminates because they cause the mechanical properties (stiffness, strength) of the laminate to be reduced. As well known for ultrasonic technique for evaluating the defect of CFRP composite laminates, a pitch-catch technique was found to be more practical than normal incidence backwall echo of longitudinal wave to arbitrary flaws in the composite, including fiber orientation, low level porosity, ply waviness, and cracks. The measurement depth using Rayleigh probes can be increased by increasing the separation distance of the transmitting and receiving probes. Also, with the aid of the automatic scanner, the one-sided pitch-catch probe was used to produce C-scan images for mapping out the images with beam profiles. Especially pitch-catch beam path was nondestructively characterized for the specimens when measuring a peak-to-peak amplitude and time-of-flight in order to build the beam profile modeling in the unidirectional CFRP composite laminates. Also, the pitch-catch simulation was performed to predict the beam profile trend of wave propagation in the unidirectional CF/Epoxy composite laminates. Therefore, it is found that the experimentally Rayleigh wave variation of pitch-catch ultrasonic signal was consistent with simulated results and one-side ultrasonic measurement might be very useful to detect the defects in CFRP composites.

  10. Implementing MPI-IO atomic mode and shared file pointers using MPI one-sided communication.

    SciTech Connect

    Latham, R.; Ross, R.; Thakur, R.; Mathematics and Computer Science

    2007-07-01

    The ROMIO implementation of the MPI-IO standard provides a portable infrastructure for use on top of a variety of underlying storage targets. These targets vary widely in their capabilities, and in some cases additional effort is needed within ROMIO to support all MPI-IO semantics. Two aspects of the interface that can be problematic to implement are MPI-IO atomic mode and the shared file pointer access routines. Atomic mode requires enforcing strict consistency semantics, and shared file pointer routines require communication and coordination in order to atomically update a shared resource. For some file systems, native locks may be used to implement these features, but not all file systems have lock support. In this work, we describe algorithms for implementing efficient mutex locks using MPI-1 and the one-sided capabilities from MPI-2. We then show how these algorithms may be used to implement both MPI-IO atomic mode and shared file pointer methods for ROMIO without requiring any features from the underlying file system. We show that these algorithms can outperform traditional file system lock approaches. Because of the portable nature of these algorithms, they are likely useful in a variety of situations where distributed locking or coordination is needed in the MPI-2 environment.

  11. Multiple Use One-Sided Hypotheses Testing in Univariate Linear Calibration

    NASA Technical Reports Server (NTRS)

    Krishnamoorthy, K.; Kulkarni, Pandurang M.; Mathew, Thomas

    1996-01-01

    Consider a normally distributed response variable, related to an explanatory variable through the simple linear regression model. Data obtained on the response variable, corresponding to known values of the explanatory variable (i.e., calibration data), are to be used for testing hypotheses concerning unknown values of the explanatory variable. We consider the problem of testing an unlimited sequence of one sided hypotheses concerning the explanatory variable, using the corresponding sequence of values of the response variable and the same set of calibration data. This is the situation of multiple use of the calibration data. The tests derived in this context are characterized by two types of uncertainties: one uncertainty associated with the sequence of values of the response variable, and a second uncertainty associated with the calibration data. We derive tests based on a condition that incorporates both of these uncertainties. The solution has practical applications in the decision limit problem. We illustrate our results using an example dealing with the estimation of blood alcohol concentration based on breath estimates of the alcohol concentration. In the example, the problem is to test if the unknown blood alcohol concentration of an individual exceeds a threshold that is safe for driving.

  12. Demonstration of energy-coded Compton scatter tomography with fan beams for one-sided inspection

    NASA Astrophysics Data System (ADS)

    Evans, Brian L.; Martin, Jeffrey B.; Burggraf, Larry W.; Roggemann, M. C.; Hangartner, T. N.

    2002-03-01

    An instrument is demonstrated whereby radiographic images of a sample's electron density are compiled from the information encoded in the energy spectra of gamma rays backscattered from one side of the sample. It is assumed that access is restricted to only one surface of the object under inspection. Use of energy coding allows imaging in a fan beam rather than independent interrogation of individual volume elements. The Multiplexed Compton Scatter Tomograph instrument consists of an array of high-energy-resolution detectors and fan beam collimators. Instrument signals are converted to electron density images using a penalized weighted least squares image reconstruction algorithm coupled with a deterministic system model that includes effects of Doppler broadening. The proof-of-principle instrument is demonstrated on aluminum samples. In an 8 mm thick sample with a 4 mm void in its center, contrast recovery of 90% is achieved. In a 10 mm thick sample with a 3 mm void at the back about 85% of the contrast is recovered.

  13. Five on one side: personal and social information in spatial choice.

    PubMed

    Brown, Michael F; Saxon, Marie E; Bisbing, Teagan; Evans, Jessica; Ruff, Jennifer; Stokesbury, Andrew

    2015-03-01

    To examine whether the outcome of a rat's own choices ("personal information") and the choice behavior of another rat ("social information") can jointly control spatial choices, rats were tested in an open field task in which they searched for food. For the rats of primary interest (Subject Rats), the baited locations were all on one side of the arena, but the specific locations baited and the side on which they occurred varied over trials. The Subject Rats were sometimes tested together with an informed "Model" rat that had learned to find food in the same five locations (all on the same side of the arena) on every trial. Unintended perceptual cues apparently controlled spatial choices at first, but when perceptual cues to food location were not available, choices were controlled by both personal information (allowing the baited side of the arena to be determined) and social information (allowing baited locations to be determined more precisely). This shows that control by personal and social information are not mutually exclusive and supports the view that these two kinds of information can be used flexibly and adaptively to guide spatial choices. This article is part of a Special Issue entitled: tribute to Tom Zentall. PMID:25572458

  14. One-sided surface modification of cellulose fabric by printing a modified TEMPO-mediated oxidant.

    PubMed

    Fitz-Binder, Christa; Bechtold, Thomas

    2014-06-15

    One-sided surface oxidation of lyocell type cellulose fabric can be achieved by use of a modified TEMPO-mediated oxidation system. A borate-based buffer was used to maintain stable pH conditions and screen printing was applied to achieve oxidation on the fabric surface only. To formulate an applicable procedure, the TEMPO/NaBr/NaOCl system was split into two treatment steps: firstly, the fabric was impregnated with a buffered TEMPO/NaBr solution and dried, then a thickened NaOCl paste was printed on the fabric. FTIR-ATR spectra and methylene blue sorption experiments demonstrated successful modification on the printed side of the fabric. Substantial increases in carboxylic group content and water retention value were observed. The higher concentration of carboxylic groups on the fabric surface also led to a localised increase in binding capacity for Ca(2+)-ions. This new concept permits controlled oxidation of cellulose surfaces by printing techniques. PMID:24721061

  15. One sided bypass for bilateral Moyamoya disease, a case report and review of the literatures

    PubMed Central

    Li, Xuhui; Zhao, Ninghui; Yang, P. Zichu

    2016-01-01

    Background Moyamoya disease (MMD) is a rare condition, where the most appropriate treatment for it is yet to be determined. Surgery remains an important method of choice although it is considered a form of palliative care. The outcome following surgery is very difficult to judge, and there is no standardised measurement to assess it. It is therefore important to know which approach for such patient is adequate. Clinical presentation A 21-year-old male patient presented with signs and symptoms of intracranial haemorrhage. Upon investigation, a diagnosis of bilateral MMD was made, and one sided direct bypass surgery was subsequently performed. At 3-year follow-up, there is no evidence of recurrent cerebral vascular event. Conclusion This case provided further evidence that direct bypass surgery is beneficial for patient in terms of blood flow improvement and symptom relieve. Although there is no consensus on whether bilateral surgical intervention is mandatory for patient with bilateral MMD, unilateral bypass might be sufficient enough. Further study is required to evaluate the best approach for such group of patient. PMID:27016648

  16. Large Scale Frequent Pattern Mining using MPI One-Sided Model

    SciTech Connect

    Vishnu, Abhinav; Agarwal, Khushbu

    2015-09-08

    In this paper, we propose a work-stealing runtime --- Library for Work Stealing LibWS --- using MPI one-sided model for designing scalable FP-Growth --- {\\em de facto} frequent pattern mining algorithm --- on large scale systems. LibWS provides locality efficient and highly scalable work-stealing techniques for load balancing on a variety of data distributions. We also propose a novel communication algorithm for FP-growth data exchange phase, which reduces the communication complexity from state-of-the-art O(p) to O(f + p/f) for p processes and f frequent attributed-ids. FP-Growth is implemented using LibWS and evaluated on several work distributions and support counts. An experimental evaluation of the FP-Growth on LibWS using 4096 processes on an InfiniBand Cluster demonstrates excellent efficiency for several work distributions (87\\% efficiency for Power-law and 91% for Poisson). The proposed distributed FP-Tree merging algorithm provides 38x communication speedup on 4096 cores.

  17. Evaluation of an experimental short-length annular combustor: One-side-entry dilution airflow concept

    NASA Technical Reports Server (NTRS)

    Humenik, F. M.; Biaglow, J. A.

    1973-01-01

    A test program was conducted to evaluate an experimental short-length annular combustor that uses a one-side-entry dilution airflow concept. The combustor design features scoops on the outer liner for controlling the primary- and secondary-zone airflow distribution. Combustor inlet total pressures were limited to 62 N/sq cm (90 psia) with inlet-air temperatures from 590 K (600 F) to 890 K (1150 F). At a diffuser inlet Mach number of 0.25, the exit temperature pattern factor was 0.44 with an average exit temperature of 1436 K (2124 F) and a total pressure loss of 4.3 percent. At a diffuser inlet Mach number of 0.31, the exit temperature pattern factor was reduced to 0.29 with an average exit temperature of 1450 K (2151 F) and a total pressure loss of 6.1 percent. Nominal combustion efficiencies of 100 percent were obtained with the ASTM A-1 fuel. Exhaust gas emissions, smoke, and altitude relight data are included with exit-temperature profiles and distribution patterns.

  18. Convective heat transfer in a high aspect ratio minichannel heated on one side

    SciTech Connect

    Forrest, Eric C.; Hu, Lin -Wen; Buongiorno, Jacopo; McKrell, Thomas J.

    2015-10-21

    Experimental results are presented for single-phase heat transfer in a narrow rectangular minichannel heated on one side. The aspect ratio and gap thickness of the test channel were 29:1 and 1.96 mm, respectively. Friction pressure drop and Nusselt numbers are reported for the transition and fully turbulent flow regimes, with Prandtl numbers ranging from 2.2 to 5.4. Turbulent friction pressure drop for the high aspect ratio channel is well-correlated by the Blasius solution when a modified Reynolds number, based upon a laminar equivalent diameter, is utilized. The critical Reynolds number for the channel falls between 3500 and 4000, with Nusselt numbers in the transition regime being reasonably predicted by Gnielinski's correlation. The dependence of the heat transfer coefficient on the Prandtl number is larger than that predicted by circular tube correlations, and is likely a result of the asymmetric heating. The problem of asymmetric heating condition is approached theoretically using a boundary layer analysis with a two-region wall layer model, similar to that originally proposed by Prandtl. The analysis clarifies the influence of asymmetric heating on the Nusselt number and correctly predicts the experimentally observed trend with Prandtl number. Furthermore, a semi-analytic correlation is derived from the analysis that accounts for the effect of aspect ratio and asymmetric heating, and is shown to predict the experimental results of this study with a mean absolute error (MAE) of less than 5% for 4000 < Re < 70,000.

  19. Continuum behavior of lattice QED, discretized with one-sided lattice differences, in one-loop order

    SciTech Connect

    Sadooghi, N.; Rothe, H.J.

    1997-06-01

    A lattice action for QED is considered, where the derivatives in the Dirac operator are replaced by one-sided lattice differences. A systematic expansion in the lattice spacing of the one-loop contribution to the fermion self-energy, vacuum polarization tensor, and vertex function is carried out for an arbitrary choice of one-sided lattice differences. It is shown that only the vacuum polarization tensor possesses the correct continuum limit, while the fermion self-energy and vertex function receive noncovariant contributions. A lattice action, discretized with a fixed choice of one-sided lattice differences, therefore, does not define a renormalizable field theory. The noncovariant contributions can, however, be eliminated by averaging the expression over all possible choices of one-sided lattice differences. {copyright} {ital 1997} {ital The American Physical Society}

  20. Convective heat transfer in a high aspect ratio minichannel heated on one side

    DOE PAGESBeta

    Forrest, Eric C.; Hu, Lin -Wen; Buongiorno, Jacopo; McKrell, Thomas J.

    2015-10-21

    Experimental results are presented for single-phase heat transfer in a narrow rectangular minichannel heated on one side. The aspect ratio and gap thickness of the test channel were 29:1 and 1.96 mm, respectively. Friction pressure drop and Nusselt numbers are reported for the transition and fully turbulent flow regimes, with Prandtl numbers ranging from 2.2 to 5.4. Turbulent friction pressure drop for the high aspect ratio channel is well-correlated by the Blasius solution when a modified Reynolds number, based upon a laminar equivalent diameter, is utilized. The critical Reynolds number for the channel falls between 3500 and 4000, with Nusseltmore » numbers in the transition regime being reasonably predicted by Gnielinski's correlation. The dependence of the heat transfer coefficient on the Prandtl number is larger than that predicted by circular tube correlations, and is likely a result of the asymmetric heating. The problem of asymmetric heating condition is approached theoretically using a boundary layer analysis with a two-region wall layer model, similar to that originally proposed by Prandtl. The analysis clarifies the influence of asymmetric heating on the Nusselt number and correctly predicts the experimentally observed trend with Prandtl number. Furthermore, a semi-analytic correlation is derived from the analysis that accounts for the effect of aspect ratio and asymmetric heating, and is shown to predict the experimental results of this study with a mean absolute error (MAE) of less than 5% for 4000 < Re < 70,000.« less

  1. Structural and electronic properties of free standing one-sided and two-sided hydrogenated silicene: A first principle study

    SciTech Connect

    Mohan, Brij Kumar, Ashok Ahluwalia, P. K.

    2014-04-24

    We performed first-principle study of the structural and electronic properties of two-dimensional hydrogenated silicene for two configurations; one is hydrogenation along one side of silicene sheet and second is hydrogenation in both sides of silicene sheet. The one-side hydrogenated silicene is found stable at planar geometry while increased buckling of 0.725 Å is found for both-side hydrogenated silicene. The result shows that the hydrogenation occupy the extended π-bonding network of silicene, and thus it exhibits semi-conducting behaviour with a band gap of 1.77 eV and 2.19 eV for one-side hydrogenated silicene and both-side hydrogenated silicene respectively. However, both-side hydrogenated silicene of binding energy 4.56 eV is more stable than one-side hydrogenated silicene of binding energy 4.30 eV, but experimentally silicene is synthesized on substrates which interacts one side of silicene layer and only other side is available for H-atoms. Therefore, practically one-side hydrogenation is also important.

  2. Determination of the bending and buckling effect in the stress analysis of shell structures accessible from one side only

    NASA Technical Reports Server (NTRS)

    Dose, A

    1941-01-01

    The present report describes a device for ascertaining the bending and buckling effect in stress measurements on shell structures accessible from one side only. Beginning with a discussion of the relationship between flexural strain and certain parameters, the respective errors of the test method for great or variable skin curvature within the test range are analyzed and illustrated by specimen example.

  3. A Dual-Column Solid Phase Extraction Strategy for Online Collection and Preparation of Continuously Flowing Effluent Streams for Mass Spectrometry

    PubMed Central

    Enders, Jeffrey R.; Marasco, Christina C.; Wikswo, John P.

    2012-01-01

    Current desalination techniques for mass spectrometry-based protocols are problematic for performing temporal response studies where increased temporal resolution requires small samples and faster sampling frequencies, which greatly increases the number of samples and sample preparation time. These challenges are pertinent to cellular dynamics experiments, where it is important to sample the biological system frequently and with as little sample waste as possible. To address these needs, we present a dual-column online solid phase extraction (SPE) approach capable of preconcentrating and preparing a constantly perfusing sample stream, with minimal to no sample loss. This strategy is evaluated for use in microfluidic bioreactor studies specifically aimed at characterizing suitable sample flow rates, temporal resolving power, and analyte concentrations. In this work we demonstrate that this strategy may be used for flow rates as low as 500 nL/min, with temporal resolving power on the order of 3 minutes, with analyte loadings ranging from fmol to pmol for metabolites. Under these conditions recoveries of ca. 80% are obtained even at fmol loadings. PMID:22967262

  4. [Multiresidue analysis of nitrogen-containing and sulfur-containing pesticides in agricultural products using dual-column GC-NPD/FPD].

    PubMed

    Ueno, Eiji; Oshima, Harumi; Saito, Isao; Matsumoto, Hiroshi

    2002-04-01

    We investigated simultaneous analytical methods for pesticide residues in large numbers of agricultural products samples. Extraction of each sample with acetonitrile was followed by a salting-out step using a graduated cylinder. The test solution was cleaned up with gel permeation chromatography (GPC), which separated the pesticide eluate into 2 fractions, and then with a tandem mini-column. Analysis was done with a dual-column GC equipped with a dual NPD and FPD (S mode) detector. Use of the Siltek-deactivated liner, guard column, and Y connector, and Silcosteel-treated NPD jet was effective for preventing the breakdown of sulfur-containing pesticides. Recoveries of 87 nitrogen-containing and sulfur-containing pesticides from fortified spinach, tomato, apple, strawberry and brown rice, ranged from 71 to 127% with RSD values of 1-24%, except for recoveries of aldicarb, amitraz, ethiofencarb, imazalil, propamocarb and triflumizole. Detection limits of pesticides were very good (0.3-5 ppb (NPD) and 2-20 ppb (FPD)) for routine analysis of pesticide residues in foods. Surveillance of pesticides in agricultural products was carried out by using the present method. From 22 out of 33 samples, 21 pesticides (43 in total) were detected. The results indicated that the present method can be applied as an efficient and reliable means for monitoring pesticide residues in agricultural products. PMID:12092417

  5. Food Labeling: Serving Sizes of Foods That Can Reasonably Be Consumed at One Eating Occasion; Dual-Column Labeling; Updating, Modifying, and Establishing Certain Reference Amounts Customarily Consumed; Serving Size for Breath Mints; and Technical Amendments. Final rule.

    PubMed

    2016-05-27

    The Food and Drug Administration (FDA or we) is issuing a final rule to define a single-serving container; require dual-column labeling for certain containers; update, modify, and establish several reference amounts customarily consumed (RACCs); amend the label serving size for breath mints; and make technical amendments to various aspects of the serving size regulations. We are taking this action to provide consumers with more accurate and up-to-date information on serving sizes. PMID:27236871

  6. Lewisite Metabolites in Urine by Solid Phase Extraction-Dual Column Reversed-Phase Liquid Chromatography-Isotope Dilution Tandem Mass Spectrometry.

    PubMed

    Palcic, Jason D; Donovan, Stephen F; Jones, Janet S; Flagg, E Lindsay; Salonga, Redentor A; Mock, Walter E; Asirvatham, Victor S

    2016-07-01

    Lewisite (2-chlorovinyldichloroarsine) is a chemical warfare agent developed during World War I. A quantitative method using solid phase extraction (SPE) followed by dual column liquid chromatography (LC)-isotope dilution tandem mass spectrometry (MS-MS) was developed for the determination of (2-chlorovinyl)arsonic acid (CVAOA), a metabolite of Lewisite, in human urine. The sample was treated with hydrogen peroxide to oxidize any (2-chlorovinyl)arsonous acid (CVAA) that remained in the trivalent arsenic oxidation state. There was 1.19% (arsenic purity) of bis-(2-chlorovinyl)arsinic acid (BCVAOA), a minor Lewisite metabolite, in the stock CVAA material. The high-throughput method qualitatively assessed BCVAOA simultaneously utilizing normal-phase silica SPE followed by reversed-phase C18 LC for an orthogonal separation. The chromatographic method results in a 5.8-min cycle time with adequate retention (k' = 2.4) of CVAOA. The mass spectrometer was operated in positive electrospray ionization mode with quantitative m/z 186.9→61.0 and confirmation 186.9→91.0 mass transitions. This selective method demonstrated linearity, accuracy and reproducibility for the clinically relevant calibration range (25-3,200 µg/L as CVAA). The method detection limit was 3.3 µg/L as CVAA from a 10 µL injection. This LC-MS-MS emergency response method has a throughput of >240 samples (2.5 extracted 96-well plates) per day. PMID:27339483

  7. Forced Flow Boiling Heat Transfer Properties of Liquid Hydrogen for Manganin Plate Pasted on One Side of a Rectangular Duct

    NASA Astrophysics Data System (ADS)

    Yoneda, K.; Shirai, Y.; Shiotsu, M.; Oura, Y.; Horie, Y.; Matsuzawa, T.; Shigeta, H.; Tatsumoto, H.; Hata, K.; Naruo, Y.; Kobayashi, H.; Inatani, Y.

    In this report, we show results on the forced flow boiling heat transfer experiments for manganin plate pasted on one side of a rectangular duct. Nucleate boiling heat transfer and its Departure from Nucleate Boiling (DNB) heat flux were measured for various pressures, subcooling and flow velocities. The DNB heat fluxes are higher for higher subcooling and higher flow velocity. The DNB heat fluxes were compared with the experimental data for round tube of nearly equal equivalent diameter. The DNB heat fluxes for the rectangular duct are lower than those for the round tube.

  8. One-Sided Communication on the Myrinet-Based SMP Clusters Using the GM Message-Passing Library

    SciTech Connect

    Nieplocha, Jaroslaw; Ju, Jialin; Apra, Edoardo

    2001-12-07

    he paper describes an efficient implementation of one-sided communication on top of GM messagre passing library and Pthreads for the Myrinet-based SMP clusters. This approach avoids polling, is compatible with shared memory, and exploits pipelining, nonblocking communication, and overlapping memory registration with memory copy to maximize the transfer rate. Our implementation uses the standard distribution of GM and is compatible with MPICH/GM. Performance of our two applications was very good, and the GM port allowed them to avoid performance anomalies of the standard TCP/IP implementation when running on Myrinet.

  9. Compton imaging tomography for one-sided access NDE of nuclear power plant structures, systems, and components

    NASA Astrophysics Data System (ADS)

    Romanov, Volodymyr; Grubsky, Victor; Shoemaker, Keith

    2016-02-01

    Novel nondestructive evaluation (NDE) systems based on a recently pioneered Compton Imaging Tomography (CIT) technique are currently being developed by Physical Optics Corporation (POC). CIT provides high-resolution three-dimensional Compton scattered X-ray imaging of the internal structure of evaluated objects, using a set of acquired two-dimensional Compton scattered X-ray images of consecutive cross sections of these objects. Unlike conventional computed tomography, CIT requires only one-sided access to objects, has no limitation on the dimensions and geometry of the objects, and can be applied to large multilayer nonuniform objects with complicated geometries. Also, CIT does not require any contact with the objects being imaged during its application.

  10. One-sided imaging of large, dense objects using the 511 keV photons from induced pair production

    SciTech Connect

    Tavora, L.M.; Gilboy, W.B.; Morton, E.J.; Morgado, R.E.; Estep, R.J.; Rawool-Sullivan, M.

    1998-03-01

    The use of annihilation photons from photon-induced electron-positron pair production as a means of inspecting objects when only one side is accessible is described. The Z2 dependence of the pair production cross section and the high penetration of 511 keV photons suggest that this method should be capable of localizing high Z materials in lower Z matrices. The experimental results for the dependence of the back streaming photon yield on Z indicate that dynamic ranges of the order of 20 may be obtained for materials with 4 < Z < 82. Results for point to point images obtained in line scans of representative geometries are also shown. Simulation studies based on the EGS4 Monte Carlo code were also performed and their results show an agreement with experimental data of the order of 5%.

  11. Linker histone protects linker DNA on only one side of the core particle and in a sequence-dependent manner

    PubMed Central

    An, Woojin; Leuba, Sanford H.; van Holde, Kensal; Zlatanova, Jordanka

    1998-01-01

    The protection against micrococcal nuclease digestion afforded to chromatosomal DNA by the presence of a linker histone (H1o) has been quantitatively measured in two reconstituted systems. We have used chromatosomes reconstituted at two distinct positions on a DNA fragment containing the 5S rRNA gene from Lytechinus variegatus and at a specific position on a sequence containing Gal4- and USF-binding sites. In all cases, we find asymmetric protection, with ≈20 bp protected on one side of the core particle and no protection on the other. We demonstrated through crosslinking experiments that the result is not due to any sliding of the histone core caused by either linker histone addition or micrococcal nuclease cleavage. Because the core particle is itself a symmetric object, the preferred asymmetric location of a linker histone must be dictated by unknown elements in the DNA sequence. PMID:9520377

  12. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks

    PubMed Central

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F.; Schnabel, Roman

    2015-01-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein–Podolsky–Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components. PMID:26514280

  13. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks.

    PubMed

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F; Schnabel, Roman

    2015-01-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein-Podolsky-Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components. PMID:26514280

  14. Hybrid quantum-state joining and splitting assisted by quantum dots in one-side optical microcavities

    NASA Astrophysics Data System (ADS)

    Luo, Ming-Xing; Ma, Song-Ya; Chen, Xiu-Bo; Wang, Xiaojun

    2015-04-01

    Quantum state joining has been recently experimentally demonstrated [C. Vitelli et al., Nat. Photon. 7, 521 (2013), 10.1038/nphoton.2013.107] which can transfer two input photonic qubits into a photonic ququart. Here, we revisit these processes from a hybrid point of view. By exploring the giant optical circular birefringence induced by quantum-dot spins in one-sided optical microcavities, we introduce some deterministic joining schemes including two quantum-dot spin joining, hybrid photon and quantum-dot spin joining, and two-photon joining. The input quantum information is represented by one photon with polarization and spatial mode degrees of freedom (DOFs). These schemes are also adapted to the inverse processes called quantum state splitting because all the joining procedures are unitary and do not require projection and feed-forward steps. The fused photon is convenient for realizing elementary logic gates such as the controlled-not (cnot) gate, swap gate, and Toffoli gate. These hybrid fusion and splitting schemes provide flexible synthesis of the quantum-dot spin and photon in quantum applications. The transmission superiority of photons and storage superiority of the quantum-dot spin may be combined for quantum network communication or quantum computations.

  15. Implementation of continuous-variable quantum key distribution with composable and one-sided-device-independent security against coherent attacks

    NASA Astrophysics Data System (ADS)

    Gehring, Tobias; Händchen, Vitus; Duhme, Jörg; Furrer, Fabian; Franz, Torsten; Pacher, Christoph; Werner, Reinhard F.; Schnabel, Roman

    2015-10-01

    Secret communication over public channels is one of the central pillars of a modern information society. Using quantum key distribution this is achieved without relying on the hardness of mathematical problems, which might be compromised by improved algorithms or by future quantum computers. State-of-the-art quantum key distribution requires composable security against coherent attacks for a finite number of distributed quantum states as well as robustness against implementation side channels. Here we present an implementation of continuous-variable quantum key distribution satisfying these requirements. Our implementation is based on the distribution of continuous-variable Einstein-Podolsky-Rosen entangled light. It is one-sided device independent, which means the security of the generated key is independent of any memoryfree attacks on the remote detector. Since continuous-variable encoding is compatible with conventional optical communication technology, our work is a step towards practical implementations of quantum key distribution with state-of-the-art security based solely on telecom components.

  16. Discrete Event Execution with One-Sided and Two-Sided GVT Algorithms on 216,000 Processor Cores

    SciTech Connect

    Perumalla, Kalyan S; Park, Alfred J; Tipparaju, Vinod

    2014-01-01

    Global virtual time (GVT) computation is a key determinant of the efficiency and runtime dynamics of parallel discrete event simulations (PDES), especially on large-scale parallel platforms. Here, three execution modes of a generalized GVT computation algorithm are studied on high-performance parallel computing systems: (1) a synchronous GVT algorithm that affords ease of implementation, (2) an asynchronous GVT algorithm that is more complex to implement but can relieve blocking latencies, and (3) a variant of the asynchronous GVT algorithm to exploit one-sided communication in extant supercomputing platforms. Performance results are presented of implementations of these algorithms on up to 216,000 cores of a Cray XT5 system, exercised on a range of parameters: optimistic and conservative synchronization, fine- to medium-grained event computation, synthetic and non-synthetic applications, and different lookahead values. Performance of up to 54 billion events executed per second is registered. Detailed PDES-specific runtime metrics are presented to further the understanding of tightly-coupled discrete event dynamics on massively parallel platforms.

  17. Quasispherical fuel compression and fast ignition in a heavy-ion-driven X-target with one-sided illumination

    NASA Astrophysics Data System (ADS)

    Henestroza, Enrique; Logan, B. Grant; Perkins, L. John

    2011-03-01

    The HYDRA radiation-hydrodynamics code [M. M. Marinak et al., Phys. Plasmas 8, 2275 (2001)] is used to explore one-sided axial target illumination with annular and solid-profile uranium ion beams at 60 GeV to compress and ignite deuterium-tritium fuel filling the volume of metal cases with cross sections in the shape of an "X" (X-target). Quasi-three-dimensional, spherical fuel compression of the fuel toward the X-vertex on axis is obtained by controlling the geometry of the case, the timing, power, and radii of three annuli of ion beams for compression, and the hydroeffects of those beams heating the case as well as the fuel. Scaling projections suggest that this target may be capable of assembling large fuel masses resulting in high fusion yields at modest drive energies. Initial two-dimensional calculations have achieved fuel compression ratios of up to 150X solid density, with an areal density ρR of about 1 g/cm2. At these currently modest fuel densities, fast ignition pulses of 3 MJ, 60 GeV, 50 ps, and radius of 300 μm are injected through a hole in the X-case on axis to further heat the fuel to propagating burn conditions. The resulting burn waves are observed to propagate throughout the tamped fuel mass, with fusion yields of about 300 MJ. Tamping is found to be important, but radiation drive to be unimportant, to the fuel compression. Rayleigh-Taylor instability mix is found to have a minor impact on ignition and subsequent fuel burn-up.

  18. One-sided Post-processing for the Discontinuous Galerkin Method Using ENO Type Stencil Choosing and the Local Edge Detection Method

    SciTech Connect

    Archibald, Richard K; Gelb, Anne; Gottlieb, Sigal; Ryan, Jennifer

    2006-01-01

    In a previous paper by Ryan and Shu [Ryan, J. K., and Shu, C.-W. (2003). Methods Appl. Anal. 10(2), 295-307], a one-sided post-processing technique for the discontinuous Galerkin method was introduced for reconstructing solutions near computational boundaries and discontinuities in the boundaries, as well as for changes in mesh size. This technique requires prior knowledge of the discontinuity location in order to determine whether to use centered, partially one-sided, or one-sided post-processing. We now present two alternative stencil choosing schemes to automate the choice of post-processing stencil. The first is an ENO type stencil choosing procedure, which is designed to choose centered post-processing in smooth regions and one-sided or partially one-sided post-processing near a discontinuity, and the second method is based on the edge detection method designed by Archibald, Gelb, and Yoon [Archibald, R., Gelb, A., and Yoon, J. (2005). SIAM J. Numeric. Anal. 43, 259-279; Archibald, R., Gelb, A., and Yoon, J. (2006). Appl. Numeric. Math. (submitted)]. We compare these stencil choosing techniques and analyze their respective strengths and weaknesses. Finally, the automated stencil choices are applied in conjunction with the appropriate post-processing procedures and it is determine that the resulting numerical solutions are of the correct order.

  19. Violence between Therapy-Seeking Veterans and Their Partners: Prevalence and Characteristics of Nonviolent, Mutually Violent, and One-Sided Violent Couples

    ERIC Educational Resources Information Center

    Teten, Andra L.; Sherman, Michelle D.; Han, Xiaotong

    2009-01-01

    Among male veterans and their female partners seeking therapy for relationship issues, three violence profiles were identified based on self-reports of physical violence: nonviolent, in which neither partner reported perpetrating physical violence (44%); one-sided violent, in which one partner reported perpetrating violence (30%); and mutually…

  20. The ability to create NTD silicon technology in the IRT-T reactor in a horizontal experimental channel with one-side access

    NASA Astrophysics Data System (ADS)

    Varlachev, V. A.; Golovatsky, A. V.; Emets, E. G.; Butko, Ya A.

    2016-06-01

    The article shows the ability of creation of neutron transmutation doping (NTD) of monocrystalline silicon technology in the reactor's channel, which has a one-side access. In the article a distribution of thermal neutron flux through the length of channel and it's radius, neutron spectrum were obtained which confirmed that horizontal experimental channel HEC-1 is suitable for NTD.

  1. An assessment of COMSCAN, a Compton backscatter imaging camera, for the one-sided non-destructive inspection of aerospace components

    NASA Astrophysics Data System (ADS)

    Sponder, L.

    1993-07-01

    This report presents some results obtained using a Compton backscatter imaging camera, developed by Philips Industries, which were obtained during a visit to the Defense Research Establishment Pacific (DREP) during May/June 1992. Compton backscatter imaging is an X-ray technique which can be used to non-destructively inspect the interior of both metallic and non-metallic structures and, unlike conventional X-ray methods, requires access to only one side of the part being inspected.

  2. Canine Distemper Virus Infects Canine Keratinocytes and Immune Cells by Using Overlapping and Distinct Regions Located on One Side of the Attachment Protein▿

    PubMed Central

    Langedijk, Johannes P. M.; Janda, Jozef; Origgi, Francesco C.; Örvell, Claes; Vandevelde, Marc; Zurbriggen, Andreas; Plattet, Philippe

    2011-01-01

    The morbilliviruses measles virus (MeV) and canine distemper virus (CDV) both rely on two surface glycoproteins, the attachment (H) and fusion proteins, to promote fusion activity for viral cell entry. Growing evidence suggests that morbilliviruses infect multiple cell types by binding to distinct host cell surface receptors. Currently, the only known in vivo receptor used by morbilliviruses is CD150/SLAM, a molecule expressed in certain immune cells. Here we investigated the usage of multiple receptors by the highly virulent and demyelinating CDV strain A75/17. We based our study on the assumption that CDV-H may interact with receptors similar to those for MeV, and we conducted systematic alanine-scanning mutagenesis on CDV-H throughout one side of the β-propeller documented in MeV-H to contain multiple receptor-binding sites. Functional and biochemical assays performed with SLAM-expressing cells and primary canine epithelial keratinocytes identified 11 residues mutation of which selectively abrogated fusion in keratinocytes. Among these, four were identical to amino acids identified in MeV-H as residues contacting a putative receptor expressed in polarized epithelial cells. Strikingly, when mapped on a CDV-H structural model, all residues clustered in or around a recessed groove located on one side of CDV-H. In contrast, reported CDV-H mutants with SLAM-dependent fusion deficiencies were characterized by additional impairments to the promotion of fusion in keratinocytes. Furthermore, upon transfer of residues that selectively impaired fusion induction in keratinocytes into the CDV-H of the vaccine strain, fusion remained largely unaltered. Taken together, our results suggest that a restricted region on one side of CDV-H contains distinct and overlapping sites that control functional interaction with multiple receptors. PMID:21849439

  3. Importance of wave-number dependence of Biot numbers in one-sided models of evaporative Marangoni instability: Horizontal layer and spherical droplet.

    PubMed

    Machrafi, H; Rednikov, A; Colinet, P; Dauby, P C

    2015-05-01

    A one-sided model of the thermal Marangoni instability owing to evaporation into an inert gas is developed. Two configurations are studied in parallel: a horizontal liquid layer and a spherical droplet. With the dynamic gas properties being admittedly negligible, one-sided approaches typically hinge upon quantifying heat and mass transfer through the gas phase by means of transfer coefficients (like in the Newton's cooling law), which in dimensionless terms eventually corresponds to using Biot numbers. Quite a typical arrangement encountered in the literature is a constant Biot number, the same for perturbations of different wavelengths and maybe even the same as for the reference state. In the present work, we underscore the relevance of accounting for its wave-number dependence, which is especially the case in the evaporative context with relatively large values of the resulting effective Biot number. We illustrate the effect in the framework of the Marangoni instability thresholds. As a concrete example, we consider HFE-7100 (a standard refrigerant) for the liquid and air for the inert gas. PMID:26066259

  4. Optimisation and application of accelerated solvent extraction and flash chromatography for quantification of PCBs in tree barks and XAD-2 passive samplers using GC-ECD with dual columns.

    PubMed

    Guéguen, Florence; Stille, Peter; Millet, Maurice

    2013-07-15

    An analytical method for the quantification of Polychlorinated biphenyls (PCBs) concentrations in XAD-2 passive air samplers (PAS) and tree barks collected close to the Rhine River between France and Germany was developed. This method used Accelerated Solvent Extraction (ASE) followed by a purification step by flash chromatography using a 4gr cartridge (3 g of silica gel and 1 g of 44% acidified silica) and analysis by GC-ECD with dual columns. Quantification (QL) and detection (DL) limits varied 0.5 from and 5.7 ng PAS(-1) and from 0.5 and 3.0 ng PAS(-1) respectively. For tree barks, quantification and detection limits were calculated for each congener on washed tree bark sample with a signal to noise ratio of 3:1 and 10:1 (corresponding to a LQ in the range of 1-4 ng per bark sample by congeners). Uncertainties on each congener concentration were calculated to be in the range of 3-20% XAD-2 passive samplers were field calibrated by using Hi-vol. Samplers. Sampling rates of 4.2, 11.5, 1.6, and 7.9 m(3) PAS(-1) d(-1) for tri-, tetra-, penta- hexa-PCBs, respectively were obtained and are comparable to those already obtained with PUF-PAS for gas phase only (gas/particle distribution was 90/10). Method was applied to real atmospheric samples collected by XAD-2 passive samplers and tree barks in the east of France. PMID:23622537

  5. Dynamic evolution of continental and oceanic lithosphere in global mantle convection model with plate-like tectonics and one sided subduction.

    NASA Astrophysics Data System (ADS)

    Ulvrova, Martina; Coltice, Nicolas; Tackley, Paul

    2015-04-01

    Drifting of continents, spreading of the seafloor and subduction at convergent boundaries shape the surface of the Earth. On the timescales of several hundreds of millions of years, divergent boundaries at mid-ocean ridges are created and destroyed in within the Wilson cycle. This controls the evolution of the Earth as it determines the heat loss out. Presence of floating continents facilitates the Earth-like mobile lid style of convection as convective stresses are concentrated on the rheological boundary between oceanic and continental lithosphere. Subducting slabs allow for the surface material to be buried down into the mantle and have an important effect on surface tectonics. The main feature of the subduction zones observed on Earth is that it is single-sided forming the deep trenches. Recently, different numerical models were successful in reproducing one-sided subduction by allowing for the vertical deformation of the Earth surface (Crameri and Tackley 2014). In the meantime, advances were made in modelling continental break-up and formation (Rolf et al. 2014). In this study we perform numerical simulations of global mantle convection in spherical annulus geometry with strongly depth and temperature dependent rheology using StagYY code (Tackley 2008). In these models plate tectonics is generated self-consistently and features one-sided subduction on ocean-ocean plate boundary as well as floating continents. We focus on determining (1) the influence of one-sided subduction on the dynamics of the system (2) formation and breakup of continents. Rerefences: Crameri, F. and P. J. Tackley, Spontaneous development of arcuate single-sided subduction in global 3-D mantle convection models with a free surface, J. Geophys. Res., 119(7), 5921-5942, 2014. Rolf, T., N. Coltice and P. J. Tackley (2014), Statistical cyclicity of the supercontinent cycle, Geophys. Res. Lett. 41, 2014. Tackley, P. J., Modellng compressible mantle convection with large viscosity contrasts in

  6. Photoluminescence study of {InxGa1-xAs}/{InyAl1-yAs} one-side-modulation-doped asymmetric step quantum wells

    NASA Astrophysics Data System (ADS)

    Li, Hanxuan; Wang, Zhanguo; Liang, Jiben; Xu, Bo; Jiang, Chao; Gong, Qian; Liu, Fengqi; Zhou, Wei

    1998-06-01

    Fourier transform photoluminescence measurements were carried out to investigate the optical transitions in {InxGa1-xAs}/{InyAl1-yAs} one-side-modulation-doped asymmetric step quantum wells. Samples with electron density ns between 0.8 and 5.3 × 10 12cm -2 are studied. Strong recombination involving one to three populated electron subbands with the first heavyhole subband is observed. Fermi edge singularity (FES) clearly can be observed for some samples. The electron subband energies in the {InGaAs}/{InAlAs} step quantum wells were calculated by a self-consistent method, taking into account strain and nonparabolicity effects and the comparison with the experimental data shows a good agreement. Our results can help improve understanding for the application of {InGaAs}/{InAlAs} step quantum wells in microelectronic and optoelectronic devices.

  7. Low voltage charge-balanced capacitance-voltage conversion circuit for one-side-electrode-type fluid-based inclination sensor

    NASA Astrophysics Data System (ADS)

    Manaf, Asrulnizam Bin Abd; Matsumoto, Yoshinori

    2009-01-01

    A low voltage detection circuit for a capacitance sensor is important for connection to a low voltage digital circuit interface. We studied two different charge-balanced capacitance-voltage ( C- V) conversion circuits configurations; the operational amplifier and the inverter amplifier. Both capacitance detection circuits were designed using 0.35 μm CMOS circuitry technology. Both amplifiers used in the detection circuits were not affected by offset voltage. The current consumption for capacitance detection circuit was reduced from 250 μA at V dd 3.3 V to 38 μA at V dd 1.3 V by switching from an operational amplifier to an inverter amplifier. These circuits were packaged with one-side-electrode-type fluid-based inclination sensors on ceramic substrates. The size of the sensor is ∅ 4.0 mm × 1.0 mm and pure propylene carbonate was used as electrolyte. Changes in temperature did not affect the output voltage of the sensor between -10 °C and 50 °C. This results show that the inverter amplifier used in the detection circuit was not affected by offset voltage and the output voltage V m is depends only on capacitor ratio. The capacitance detection circuit using the inverter amplifier shows a high-sensitivity of about 7 mV/deg over the operational amplifier at V dd 1.3 V. The response time, resolution and minimum moving angle of sensor were 0.7 s, 0.86° and 0.4°, respectively, at V dd 1.3 V for the inverter amplifier type of capacitance detection circuit.

  8. Fuel or irradiation subassembly

    DOEpatents

    Seim, O.S.; Hutter, E.

    1975-12-23

    A subassembly for use in a nuclear reactor is described which incorporates a loose bundle of fuel or irradiation pins enclosed within an inner tube which in turn is enclosed within an outer coolant tube and includes a locking comb consisting of a head extending through one side of the inner sleeve and a plurality of teeth which extend through the other side of the inner sleeve while engaging annular undercut portions in the bottom portion of the fuel or irradiation pins to prevent movement of the pins.

  9. [Wellness holidays--wholesome wish or one-sided reality].

    PubMed

    Müller, H; Kaufmann, E L

    2001-04-01

    The term wellness is widely used in European tourism. The principal observations regarding the wellness industry concern an expanding supply of and an insufficiently researched demand for wellness programs. The quality dimension of wellness services is increasingly becoming the decisive competitive factor. For this reason quality management plays an important role. Market research shows that average 3- to 5-star hotels provide fairly comprehensive wellness facilities. Wellness hotels should therefore specialize in health information, individual care and a wide range of cultural and relaxation programs. Although the same hotel can host cure and wellness guests at the same time, these two segments have to be considered separately when deciding on the marketing strategy. We therefore assume that wellness is pursued solely by 'healthy' people, the prime aim being prevention. 'Normal cure guests' aim to heal their illness. PMID:11344947

  10. One-sided ejaculation of echidna sperm bundles.

    PubMed

    Johnston, S D; Smith, B; Pyne, M; Stenzel, D; Holt, W V

    2007-12-01

    We report for the first time an unusual ejaculatory mechanism in the short-beaked echidna in which each side of the bilaterally symmetrical, rosettelike glans penis is used alternately, with the other being shut down. This is unparalleled in mammals but is reminiscent of the use of hemipenes in squamate reptiles, providing further reproductive evidence of a sauropsidian lineage in the Monotremata. Further, we describe the occurrence of motile sperm bundles in ejaculated echidna semen and provide scanning electron micrographs of their morphology. Sperm bundling appears to confer increased sperm motility, which may provide the potential for sperm competition between males. PMID:18171162

  11. [Food irradiation].

    PubMed

    Migdał, W

    1995-01-01

    A worldwide standard on food irradiation was adopted in 1983 by Codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and the World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Institute of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19MeV, 1 kW) and an industrial unit Elektronika (10MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permission for irradiation for: spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables. PMID:8619113

  12. Tissue irradiator

    DOEpatents

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-12-16

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in- vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood- carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170.

  13. Irradiation subassembly

    DOEpatents

    Seim, O.S.; Filewicz, E.C.; Hutter, E.

    1973-10-23

    An irradiation subassembly for use in a nuclear reactor is described which includes a bundle of slender elongated irradiation -capsules or fuel elements enclosed by a coolant tube and having yieldable retaining liner between the irradiation capsules and the coolant tube. For a hexagonal bundle surrounded by a hexagonal tube the yieldable retaining liner may consist either of six segments corresponding to the six sides of the tube or three angular segments each corresponding in two adjacent sides of the tube. The sides of adjacent segments abut and are so cut that metal-tometal contact is retained when the volume enclosed by the retaining liner is varied and Springs are provided for urging the segments toward the center of the tube to hold the capsules in a closely packed configuration. (Official Gazette)

  14. Irradiance gradients

    SciTech Connect

    Ward, G.J. Ecole Polytechnique Federale, Lausanne ); Heckbert, P.S. . School of Computer Science Technische Hogeschool Delft . Dept. of Technical Mathematics and Informatics)

    1992-04-01

    A new method for improving the accuracy of a diffuse interreflection calculation is introduced in a ray tracing context. The information from a hemispherical sampling of the luminous environment is interpreted in a new way to predict the change in irradiance as a function of position and surface orientation. The additional computation involved is modest and the benefit is substantial. An improved interpolation of irradiance resulting from the gradient calculation produces smoother, more accurate renderings. This result is achieved through better utilization of ray samples rather than additional samples or alternate sampling strategies. Thus, the technique is applicable to a variety of global illumination algorithms that use hemicubes or Monte Carlo sampling techniques.

  15. Irradiated foods

    MedlinePlus

    ... it reduces the risk of food poisoning . Food irradiation is used in many countries. It was first approved in the U.S. to prevent sprouts on white potatoes, and to control insects on wheat and in certain spices and seasonings.

  16. Simultaneous extraction of six pesticides using a dual-column extraction procedure

    SciTech Connect

    Watts, D.W.; Bogus, E.R.; Hall, J.K.; Mumma, R.O.

    1994-03-01

    A method was developed that allowed for the simultaneous extraction of six pesticides (three chloro-s-triazines, a substituted amide, an organic phosphate, and a benzoic acid derivative) from either sod or water samples. This rnethod utilizes two types of solid-phase extraction columns, one reverse phase, and one anion exchange column, connected in series to extract all six compounds from a single sample. After separate elution of the two columns, high pressure liquid chromatography was employed to analyze the benzoic acid derivative utilizing a C-18 column and paired Ion techniques with a detection limit of 6 {mu}g L{sup -1}. A gas chromatography equipped with a N-P detector, was used to analyze the remaining five compounds. The detectable limit for the chloro-s-triazines was 3 {mu}g L{sup -1} while the detection limit of the substituted amide was 6 {mu}g L{sup -1}. 11 refs., 1 fig., 1 tab.

  17. Evaluation of 10MeV proton irradiation on 5.5 Mpixel scientific CMOS image sensor

    NASA Astrophysics Data System (ADS)

    Vu, Paul; Fowler, Boyd; Rodricks, Brian; Balicki, Janusz; Mims, Steve..; Li, Wang

    2010-10-01

    We evaluate the effects of 10 MeV proton irradiation on the performance of a 5.5 Mpixel scientific grade CMOS image sensor based on a 5T pixel architecture with pinned photodiode and transfer gate. The sensor has on-chip dual column level amplifiers and 11-bit single slope analog to digital converters (ADC) for high speed readout and wide dynamic range. The operation of the sensor is programmable and controlled by on-chip digital control modules. Since the image sensor features two identical halves capable of operating independently, we used a mask to expose only one half of the sensor to the proton beam, leaving the other half intact to serve as a reference. In addition, the pixel array and the digital logic control section were irradiated separately, at dose rates varying from 4 rad/s to 367 rad/s, for a total accumulated dose of 146 krad(Si) to assess the radiation effects on these key components of the image sensor. We report the resulting damage effects on the performance of the sensor including increase in dark current, temporal noise, dark spikes, transient effects and latch-up. The dark signal increased by about 55 e-/pixel after exposure to 14 krad (Si) and the dark noise increased from about 2.75e- to 6.5e-. While the number of hot pixels increased by 6 percent and the dark signal non uniformity degraded, no catastrophic failure mechanisms were observed during the tests, and the sensor did not suffer from functional failures.

  18. Use of Irradiated Foods

    NASA Technical Reports Server (NTRS)

    Brynjolfsson, A.

    1985-01-01

    The safety of irradiated foods is reviewed. Guidelines and regulations for processing irradiated foods are considered. The radiolytic products formed in food when it is irradiated and its wholesomeness is discussed. It is concluded that food irradiation processing is not a panacea for all problems in food processing but when properly used will serve the space station well.

  19. Detection of irradiated liquor

    NASA Astrophysics Data System (ADS)

    Shengchu, Qi; Jilan, Wu; Rongyao, Yuan

    D-2,3-butanediol is formed by irradiation processes in irradiated liquors. This radiolytic product is not formed in unirradiated liquors and its presence can therefore be used to identify whether a liquor has been irradiated or not. The relation meso/dl≈1 for 2,3-butanediol and the amount present in irradiated liquors may therefore be used as an indication of the dose used in the irradiation.

  20. Economics of food irradiation: Comparison between electron accelerators and cobalt-60

    NASA Astrophysics Data System (ADS)

    Morrison, R. M.

    The Codex Alimentarius Commission's proposed international standard permits three types of ionizing radiation to be used on foods: gamma rays from radioactive cobalt-60 or cesium-137, high energy electrons, and x-rays. The latter two types of radiation are produced by electron accelerators powered by electricity. Unlike gamma rays and x-rays which can penetrate pallet loads of foods, electrons of the allowed energy levels only penetrate 1 to 3 inches when irradiated from one side. Thus, electrons are limited to treating the surface of foods or foods in thin packages or a shallow stream of grains, powders, or liquids. Average costs per kilogram (kg) of irradiating selected foods are similar for the electron accelerator and cobalt-60 irradiators analyzed in this study, but initial investment costs generally vary by U.S. $1 million. Irradiation treatment costs range from 1 to 15 U.S. cents per kg for the foods and annual volumes examined with larger volumes having lower treatment costs. Cobalt-60 is less expensive than electrons when annual volumes are below 23 million kgs. For radiation source requirements above the equivalent of about 1 million curies of cobalt-60, electrons become more economical. The largest differences in costs occur with the papaya irradiators where using x-rays to penetrate the fruit is more expensive than using cobalt-60.

  1. Photopatch and UV-irradiated patch testing in photosensitive dermatitis

    PubMed Central

    Rai, Reena; Thomas, Maria

    2016-01-01

    Background: The photopatch test is used to detect photoallergic reactions to various antigens such as sunscreens and drugs. Photosensitive dermatitis can be caused due to antigens like parthenium, fragrances, rubbers and metals. The photopatch test does not contain these antigens. Therefore, the Indian Standard Series (ISS) along with the Standard photopatch series from Chemotechnique Diagnostics, Sweden was used to detect light induced antigens. Aim: To detect light induced antigens in patients with photosensitive dermatitis. Methods: This study was done in a descriptive, observer blinded manner. Photopatch test and ISS were applied in duplicate on the patient's back by the standard method. After 24 hours, readings were recorded according to ICDRG criteria. One side was closed and other side irradiated with 14 J/cm2 of UVA and a second set of readings were recorded after 48 hrs. Result: The highest positivity was obtained with parthenium, with 18 out of 35 (51%) patients showing a positive patch test reaction with both photoallergic contact dermatitis and photoaggravation. Four patients (11%) showed positive patch test reaction suggestive of contact dermatitis to potassium dichromate and fragrance mix. Six patients had contact dermatitis to numerous antigens such as nickel, cobalt, chinoform and para-phenylenediamine. None of these patients showed photoaggravation on patch testing. Conclusion: Parthenium was found to cause photoallergy, contact dermatitis with photoaggravation and contact allergy. Hence, photopatch test and UV irradiated patch test can be an important tool to detect light induced antigens in patients with photosensitive dermatitis. PMID:26955581

  2. Comminuting irradiated ferritic steel

    DOEpatents

    Bauer, Roger E.; Straalsund, Jerry L.; Chin, Bryan A.

    1985-01-01

    Disclosed is a method of comminuting irradiated ferritic steel by placing the steel in a solution of a compound selected from the group consisting of sulfamic acid, bisulfate, and mixtures thereof. The ferritic steel is used as cladding on nuclear fuel rods or other irradiated components.

  3. Irradiation Creep in Graphite

    SciTech Connect

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

    An understanding of the underlying mechanisms of irradiation creep in graphite material is required to correctly interpret experimental data, explain micromechanical modeling results, and predict whole-core behavior. This project will focus on experimental microscopic data to demonstrate the mechanism of irradiation creep. High-resolution transmission electron microscopy should be able to image both the dislocations in graphite and the irradiation-induced interstitial clusters that pin those dislocations. The team will first prepare and characterize nanoscale samples of virgin nuclear graphite in a transmission electron microscope. Additional samples will be irradiated to varying degrees at the Advanced Test Reactor (ATR) facility and similarly characterized. Researchers will record microstructures and crystal defects and suggest a mechanism for irradiation creep based on the results. In addition, the purchase of a tensile holder for a transmission electron microscope will allow, for the first time, in situ observation of creep behavior on the microstructure and crystallographic defects.

  4. Irradiation-Induced Nanostructures

    SciTech Connect

    Birtcher, R.C.; Ewing, R.C.; Matzke, Hj.; Meldrum, A.; Newcomer, P.P.; Wang, L.M.; Wang, S.X.; Weber, W.J.

    1999-08-09

    This paper summarizes the results of the studies of the irradiation-induced formation of nanostructures, where the injected interstitials from the source of irradiation are not major components of the nanophase. This phenomena has been observed by in situ transmission electron microscopy (TEM) in a number of intermetallic compounds and ceramics during high-energy electron or ion irradiations when the ions completely penetrate through the specimen. Beginning with single crystals, electron or ion irradiation in a certain temperature range may result in nanostructures composed of amorphous domains and nanocrystals with either the original composition and crystal structure or new nanophases formed by decomposition of the target material. The phenomenon has also been observed in natural materials which have suffered irradiation from the decay of constituent radioactive elements and in nuclear reactor fuels which have been irradiated by fission neutrons and other fission products. The mechanisms involved in the process of this nanophase formation are discussed in terms of the evolution of displacement cascades, radiation-induced defect accumulation, radiation-induced segregation and phase decomposition, as well as the competition between irradiation-induced amorphization and recrystallization.

  5. The Total Irradiance Monitors

    NASA Astrophysics Data System (ADS)

    Kopp, Greg

    2015-08-01

    The first Total Irradiance Monitor (TIM) launched on NASA’s Solar Radiation and Climate Experiment in 2003 and quickly proved to be the most accurate and stable instrument on orbit for measuring the total solar irradiance (TSI). The TIM’s design improvements over the older classical radiometers helped its selection on many subsequent missions, including NASA’s Glory, NOAA’s TSI Calibration Transfer Experiment, and the series of NASA’s Total and Spectral Solar Irradiance Sensor instruments currently underway. I will summarize the status of and differences between each of the TIMs currently on-orbit or in production.

  6. Test reactor irradiation coordination

    SciTech Connect

    Heartherly, D.W.; Siman Tov, I.I.; Sparks, D.W.

    1995-10-01

    This task was established to supply and coordinate irradiation services needed by NRC contractors other than ORNL. These services include the design and assembly of irradiation capsules as well as arranging for their exposure, disassembly, and return of specimens. During this period, the final design of the facility and specimen baskets was determined through an iterative process involving the designers and thermal analysts. The resulting design should permit the irradiation of all test specimens to within 5{degrees}C of their desired temperature. Detailing of all parts is ongoing and should be completed during the next reporting period. Procurement of the facility will also be initiated during the next review period.

  7. Alaskan Commodities Irradiation Project

    SciTech Connect

    Zarling, J.P.; Swanson, R.B.; Logan, R.R.; Das, D.K.; Lewis, C.E.; Workman, W.G.; Tumeo, M.A.; Hok, C.I.; Birklid, C.A.; Bennett, F.L.

    1988-12-01

    The ninety-ninth US Congress commissioned a six-state food irradiation research and development program to evaluate the commercial potential of this technology. Hawaii, Washington, Iowa, Oklahoma and Florida as well as Alaska have participated in the national program; various food products including fishery products, red meats, tropical and citrus fruits and vegetables have been studied. The purpose of the Alaskan study was to review and evaluate those factors related to the technical and economic feasibility of an irradiator in Alaska. This options analysis study will serve as a basis for determining the state's further involvement in the development of food irradiation technology. 40 refs., 50 figs., 53 tabs.

  8. Food irradiation in perspective

    NASA Astrophysics Data System (ADS)

    Henon, Y. M.

    1995-02-01

    Food irradiation already has a long history of hopes and disappointments. Nowhere in the world it plays the role that it should have, including in the much needed prevention of foodborne diseases. Irradiated food sold well wherever consumers were given a chance to buy them. Differences between national regulations do not allow the international trade of irradiated foods. While in many countries food irradiation is still illegal, in most others it is regulated as a food additive and based on the knowledge of the sixties. Until 1980, wholesomeness was the big issue. Then the "prerequisite" became detection methods. Large amounts of money have been spent to design and validate tests which, in fact, aim at enforcing unjustified restrictions on the use of the process. In spite of all the difficulties, it is believed that the efforts of various UN organizations and a growing legitimate demand for food safety should in the end lead to recognition and acceptance.

  9. Economics of food irradiation.

    PubMed

    Deitch, J

    1982-01-01

    This article examines the cost competitiveness of the food irradiation process. An analysis of the principal factors--the product, physical plant, irradiation source, and financing--that impact on cost is made. Equations are developed and used to calculate the size of the source for planned product throughput, efficiency factors, power requirements, and operating costs of sources, radionuclides, and accelerators. Methods of financing and capital investment are discussed. A series of tables show cost breakdowns of sources, buildings, equipment, and essential support facilities for both a cobalt-60 and a 10-MeV electron accelerator facility. Additional tables present irradiation costs as functions of a number of parameters--power input, source size, dose, and hours of annual operation. The use of the numbers in the tables are explained by examples of calculations of the irradiation costs for disinfestation of grains and radicidation of feed. PMID:6759046

  10. Irradiation of biliary carcinoma

    SciTech Connect

    Herskovic, A.; Heaston, D.; Engler, M.J.; Fishburn, R.I.; Jones, R.S.; Noell, K.T.

    1981-04-01

    External and interstitial irradiation have effected the disappearance of biliary lesions. The use of indwelling catheters in the biliary tract makes the technique more appealing. Iridium 192 implants were used.

  11. Precompaction irradiation of meteorites

    SciTech Connect

    Caffee, M.W.

    1986-01-01

    In the four meteorites studied, the nonirradiated grains show the nominal amount of spallogenic Ne and Ar expected from recent galactic cosmic ray exposure. Two conclusions follow from these observations: (1) the quality of spallogenic Ne and Ar in the irradiated grains is far more than can be explained by reasonable precompaction exposures to galactic cosmic rays. If the pre-compaction irradiation occurred in a regolith, the exposure to galactic cosmic rays would have to last several hundred m.y. for some of the grains. Similarly long ages would result if the source of the protons were solar flares with a particle flux similar to modern-day solar flares. These exposure durations are incompatible with current models for the pre-compaction irradiation of gas rich meteorites. (2) There is always a correlation between solar flare tracks and precompaction spallogenic Ne and Ar. This correlation is surprising, considering the difference in range of these two effects. Galactic cosmic rays have a range of meters whereas solar flare heavy ions have a range of less than a millimeter. This difference should largely decouple these two effects, as was shown in studies on lunar soil 60009, where both irradiated and non-irradiated grains contain large quantities of spallogenic Ne. If galactic cosmic rays are responsible for the spallogenic Ne and Ar in the irradiated grains, the authors would similarly expect the nonirradiated grains to contain large amounts of spallogenic Ne and Ar.

  12. Total lymphoid irradiation

    SciTech Connect

    Sutherland, D.E.; Ferguson, R.M.; Simmons, R.L.; Kim, T.H.; Slavin, S.; Najarian, J.S.

    1983-05-01

    Total lymphoid irradiation by itself can produce sufficient immunosuppression to prolong the survival of a variety of organ allografts in experimental animals. The degree of prolongation is dose-dependent and is limited by the toxicity that occurs with higher doses. Total lymphoid irradiation is more effective before transplantation than after, but when used after transplantation can be combined with pharmacologic immunosuppression to achieve a positive effect. In some animal models, total lymphoid irradiation induces an environment in which fully allogeneic bone marrow will engraft and induce permanent chimerism in the recipients who are then tolerant to organ allografts from the donor strain. If total lymphoid irradiation is ever to have clinical applicability on a large scale, it would seem that it would have to be under circumstances in which tolerance can be induced. However, in some animal models graft-versus-host disease occurs following bone marrow transplantation, and methods to obviate its occurrence probably will be needed if this approach is to be applied clinically. In recent years, patient and graft survival rates in renal allograft recipients treated with conventional immunosuppression have improved considerably, and thus the impetus to utilize total lymphoid irradiation for its immunosuppressive effect alone is less compelling. The future of total lymphoid irradiation probably lies in devising protocols in which maintenance immunosuppression can be eliminated, or nearly eliminated, altogether. Such protocols are effective in rodents. Whether they can be applied to clinical transplantation remains to be seen.

  13. Anticarcinogenic effect of tetrachlorodecaoxide after total-body gamma irradiation in rats

    SciTech Connect

    Kempf, S.R.; Port, R.E.; Ivankovic, S.

    1994-08-01

    Tetrachlorodecaoxygen (TCDO) therapy of acute radiation syndrome was tested for a possible influence on the development of X-ray-induced malignancies. BD IX rats were exposed to total-body irradiation (TBI, {gamma} rays, 9 or 11 Gy) and received daily intravenous injections of either TCDO or physiological saline solution from days 4 through 11 after TBI. The short-term TCDO therapy reduced the acute death rate markedly, but survival rates after 4 months were similar with and without TCDO. The first malignancy after TBI occurred on day 103, and over the lifetime of the animals the tumor incidence in the group given TBI (11 Gy) without TCDO treatment was 73% vs 20% in animals with short-term TCDO therapy after TBI. In particular, there was a highly significant prevention of radiation-induced leukemia [P (one-sided) < 0.001] by TCDO, and a significantly reduced incidence of malignant epithelial tumors [P (one-sided) < 0.05]. The development of sarcomas was not affected by TCDO. Long-term survival was not enhanced by TCDO due to the occurrence of bronchopneumonial infections about 1 year after TBI. In conclusion, TCDO is not only a potent therapeutic agent in acute radiation syndrome, but it also significantly reduced the carcinogenic risk in rats after exposure to ionizing radiation. 18 refs., 3 figs., 4 tabs.

  14. 42 CFR 425.604 - Calculation of savings under the one-sided model.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) Continuously assigned beneficiaries. (i) CMS uses demographic factors to adjust for changes in the continuously... prospective HCC risk score. (3) Assigned beneficiary changes in demographics and health status are used to... demographic changes CMS makes adjustments for separate categories for each of the following populations...

  15. Bifurcation analysis of an impact oscillator with a one-sided elastic constraint near grazing

    NASA Astrophysics Data System (ADS)

    Ing, James; Pavlovskaia, Ekaterina; Wiercigroch, Marian; Banerjee, Soumitro

    2010-03-01

    In this paper a linear oscillator undergoing impact with a secondary elastic support is studied experimentally and semi-analytically for near-grazing conditions. The experimentally observed bifurcations are explained with help from simulations based on mapping solutions between locally smooth subspaces. Smooth as well as nonsmooth bifurcations are observed, and the resulting atypical bifurcations are explained, often as an interplay between them. In order to understand the observed bifurcation scenarios, a global analysis is required, due to the influence of stable and unstable orbits which are born in distant bifurcations but become important at near-grazing conditions. The good degree of correspondence between experiment and theory fully justifies the modelling approach.

  16. Probability of Future Observations Exceeding One-Sided, Normal, Upper Tolerance Limits

    SciTech Connect

    Edwards, Timothy S.

    2014-10-29

    Normal tolerance limits are frequently used in dynamic environments specifications of aerospace systems as a method to account for aleatory variability in the environments. Upper tolerance limits, when used in this way, are computed from records of the environment and used to enforce conservatism in the specification by describing upper extreme values the environment may take in the future. Components and systems are designed to withstand these extreme loads to ensure they do not fail under normal use conditions. The degree of conservatism in the upper tolerance limits is controlled by specifying the coverage and confidence level (usually written in “coverage/confidence” form). Moreover, in high-consequence systems it is common to specify tolerance limits at 95% or 99% coverage and confidence at the 50% or 90% level. Despite the ubiquity of upper tolerance limits in the aerospace community, analysts and decision-makers frequently misinterpret their meaning. The misinterpretation extends into the standards that govern much of the acceptance and qualification of commercial and government aerospace systems. As a result, the risk of a future observation of the environment exceeding the upper tolerance limit is sometimes significantly underestimated by decision makers. This note explains the meaning of upper tolerance limits and a related measure, the upper prediction limit. So, the objective of this work is to clarify the probability of exceeding these limits in flight so that decision-makers can better understand the risk associated with exceeding design and test levels during flight and balance the cost of design and development with that of mission failure.

  17. Simultaneous One-Sided Tests with Application to Education Evaluation Systems

    ERIC Educational Resources Information Center

    Han, Bing; Dalal, Siddhartha R.; McCaffrey, Daniel F.

    2012-01-01

    There is widespread interest in using various statistical inference tools as a part of the evaluations for individual teachers and schools. Evaluation systems typically involve classifying hundreds or even thousands of teachers or schools according to their estimated performance. Many current evaluations are largely based on individual estimates…

  18. Learning one-dimensional geometric patterns under one-sided random misclassification noise

    SciTech Connect

    Goldberg, P.W.; Goldman, S.A.

    1994-07-01

    Developing the ability to recognize a landmark from a visual image of a robot`s current location is a fundamental problem in robotics. The authors consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration of k points in the real line. Each instance is a configuration of n points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. They relate the concept class of geometric patterns to the landmark recognition problem and then present a polynomial-time algorithm that PAC-learns the class of one-dimensional geometric patterns when the negative examples are corrupted by a large amount of random misclassification noise.

  19. Joint one-sided and two-sided simultaneous confidence intervals.

    PubMed

    Braat, S; Gerhard, D; Hothorn, L A

    2008-01-01

    For the analysis of multiarmed clinical trials often a set consisting of a mixture of one- and two-sided tests can be preferred over a set of common two-sided hypotheses settings. Here we show the straightforward application of existing multiple comparison procedures for the difference and ratio of normally distributed means to complex trial designs, involving one and two test directions. The proposed contrast tests provide a more flexible framework than the existing methods at nearly similar power. An application is illustrated for an example with multiple treatment doses and two active controls; statistical software codes are included for R and SAS System. PMID:18327722

  20. 42 CFR 425.604 - Calculation of savings under the one-sided model.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... beneficiaries: (i) ESRD. (ii) Disabled. (iii) Aged/dual eligible Medicare and Medicaid beneficiaries. (iv) Aged/non-dual eligible Medicare and Medicaid beneficiaries. (4) To minimize variation from catastrophically...) of this section. (b) Minimum savings rate (MSR). CMS uses a sliding scale, based on the number...

  1. 42 CFR 425.604 - Calculation of savings under the one-sided model.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... beneficiaries: (i) ESRD. (ii) Disabled. (iii) Aged/dual eligible Medicare and Medicaid beneficiaries. (iv) Aged/non-dual eligible Medicare and Medicaid beneficiaries. (4) To minimize variation from catastrophically...) of this section. (b) Minimum savings rate (MSR). CMS uses a sliding scale, based on the number...

  2. Comparison of results of experimental research with numerical calculations of a model one-sided seal

    NASA Astrophysics Data System (ADS)

    Joachimiak, Damian; Krzyślak, Piotr

    2015-06-01

    Paper presents the results of experimental and numerical research of a model segment of a labyrinth seal for a different wear level. The analysis covers the extent of leakage and distribution of static pressure in the seal chambers and the planes upstream and downstream of the segment. The measurement data have been compared with the results of numerical calculations obtained using commercial software. Based on the flow conditions occurring in the area subjected to calculations, the size of the mesh defined by parameter y+ has been analyzed and the selection of the turbulence model has been described. The numerical calculations were based on the measurable thermodynamic parameters in the seal segments of steam turbines. The work contains a comparison of the mass flow and distribution of static pressure in the seal chambers obtained during the measurement and calculated numerically in a model segment of the seal of different level of wear.

  3. Dark Matter Limits-One Sided or Two Sided or Flip-flopping?

    NASA Astrophysics Data System (ADS)

    Smith, Peter F.

    2009-09-01

    The principles of the two-branch and single-branch Neyman plots for providing two-sided or single-sided confidence intervals in the presence of background are summarized, clarifying the objections to `flip-flopping] between the two types to obtain an improved upper limit. An example of the improvement achieved by `flip-flopping' is shown, using the XENON10 published data.

  4. DNA stretching on one-sided carbon nanotube (CNT) walls in microchannels

    NASA Astrophysics Data System (ADS)

    Hsieh, Shou-Shing; Chen, Jyun-Hong; Lin, Chih-Yi; Li, Shih-Yang

    2015-04-01

    Completely stretched DNA molecules are becoming an important topic to advance our fundamental understanding of the physical and biological properties of DNA. In this study, λ phage DNA molecules are stretched on multi-walled carbon nanotube (MWCNT) films on the wall surfaces in a microchannel and measured through the total internal reflection fluorescence microscopy visualization/measuring technique. With DNA stretching in a definite direction, it is expected that a higher stretch ratio will be obtained. Real-time images show that the stretch ratio of the λ phage DNA molecules on the MWCNT walls reaches about 0.7 (relative to its contour length) at a low electrical field strength of 5 kV m-1, which is significantly higher than without the MWCNT-deposited film. Special attention is paid to the effect of the MWCNT film thickness, the channel size, in terms of the aspect ratio of the channel cross-section and channel length, and different electrical field strengths.

  5. Probability of Future Observations Exceeding One-Sided, Normal, Upper Tolerance Limits

    DOE PAGESBeta

    Edwards, Timothy S.

    2014-10-29

    Normal tolerance limits are frequently used in dynamic environments specifications of aerospace systems as a method to account for aleatory variability in the environments. Upper tolerance limits, when used in this way, are computed from records of the environment and used to enforce conservatism in the specification by describing upper extreme values the environment may take in the future. Components and systems are designed to withstand these extreme loads to ensure they do not fail under normal use conditions. The degree of conservatism in the upper tolerance limits is controlled by specifying the coverage and confidence level (usually written inmore » “coverage/confidence” form). Moreover, in high-consequence systems it is common to specify tolerance limits at 95% or 99% coverage and confidence at the 50% or 90% level. Despite the ubiquity of upper tolerance limits in the aerospace community, analysts and decision-makers frequently misinterpret their meaning. The misinterpretation extends into the standards that govern much of the acceptance and qualification of commercial and government aerospace systems. As a result, the risk of a future observation of the environment exceeding the upper tolerance limit is sometimes significantly underestimated by decision makers. This note explains the meaning of upper tolerance limits and a related measure, the upper prediction limit. So, the objective of this work is to clarify the probability of exceeding these limits in flight so that decision-makers can better understand the risk associated with exceeding design and test levels during flight and balance the cost of design and development with that of mission failure.« less

  6. Statistics of a Flux in Burgers Turbulencewith One-Sided Brownian Initial Data

    NASA Astrophysics Data System (ADS)

    Bertoin, J.; Giraud, C.; Isozaki, Y.

    We study the statistics of the flux of particles crossing the origin, which is induced by the dynamics of ballistic aggregation in dimension 1, under certain random initial conditions for the system. More precisely, we consider the cases when particles are uniformly distributed on at the initial time, and if u(x,t) denotes the velocity of the particle located at x at time t, then u(x,0)= 0 for x<0 and (u(x,0), x>= 0) is either a white noise or a Brownian motion.

  7. Quantitative ultrasonic evaluation of concrete structures using one-sided access

    NASA Astrophysics Data System (ADS)

    Khazanovich, Lev; Hoegh, Kyle

    2016-02-01

    Nondestructive diagnostics of concrete structures is an important and challenging problem. A recent introduction of array ultrasonic dry point contact transducer systems offers opportunities for quantitative assessment of the subsurface condition of concrete structures, including detection of defects and inclusions. The methods described in this paper are developed for signal interpretation of shear wave impulse response time histories from multiple fixed distance transducer pairs in a self-contained ultrasonic linear array. This included generalizing Kirchoff migration-based synthetic aperture focusing technique (SAFT) reconstruction methods to handle the spatially diverse transducer pair locations, creating expanded virtual arrays with associated reconstruction methods, and creating automated reconstruction interpretation methods for reinforcement detection and stochastic flaw detection. Interpretation of the reconstruction techniques developed in this study were validated using the results of laboratory and field forensic studies. Applicability of the developed methods for solving practical engineering problems was demonstrated.

  8. One-sided and mutually aggressive couples: Differences in attachment, conflict prevalence, and coping.

    PubMed

    Burk, William J; Seiffge-Krenke, Inge

    2015-12-01

    This study investigated concurrent links between adolescent romantic couples' reports of aggression (relational and physical) and relationship functioning (e.g., attachment security, conflict prevalence, coping strategies, jealousy, and affiliative and romantic relationship quality) using a pattern-oriented approach. The sample included 194 romantic partner dyads (Mage=16.99 years for females and Mage=18.41 years for males). A hierarchical cluster analysis identified five distinct subgroups of dyads based on male and female reports of relational and physical aggression, ranging from nonaggressive couples (42%), to those characterized by aggressive females (18%), aggressive males (14%), physically aggressive females (20%), and mutually aggressive females and males (6%). Clusters in which one partner was perceived as either relationally or physically aggressive were characterized by higher rates of conflict, less adaptive coping, and more jealousy (particularly in males). The mutually aggressive couples showed the least adaptive relationship functioning, with high rates of conflict, a deficit in reflection and emotion regulation in conflict situations, and a lack of affiliative relationship qualities. The discussion focuses on the formative character of aggression in these early romantic relations, the aggravating impact of mutual aggression on relationship functioning, and the gender-specific functions of aggression in relationships characterized by unilateral aggression. PMID:26360706

  9. One-sided ultrasonic inspection to detect flaws in CFRP composite solid laminates

    NASA Astrophysics Data System (ADS)

    Im, Kwang-Hee; Zhang, Guilina; Hsu, David K.; Barnard, Dan; Kim, Sun-Kyu; Yang, Yong-Jun; Hwang, Woo-Chae; Yang, In-Young; Park, Je-Woong

    2012-04-01

    The importance of Carbon Fiber reinforced plastics (CFRP) has been generally recognized, and the CFRP composite laminates are widely used. When ultrasonic inspection is applied on actual aircraft components, the part geometry often lacks flat and parallel faces and the benefit of a backwall echo maybe unavailable. So, it is very necessary to detect flaws and defects in the CFRP composite solid laminates due to the flaws of CFRP composite laminates affecting the properties of the laminate. Firstly, we used miniature potted angle beam transducers (designed for generating mode-converted shear waves or Rayleigh waves in steel) on solid laminates of composites. A pair of such transducers was mounted in a holder in a nose-to-nose fashion to be used as a scanning probe on composites. Secondly, a method was utilized to determine the porosity content of a composite lay-up by processing micrograph images of the laminate. The results from the image processing method are compared with existing data. C-scan images of CFRP samples, which were based on the impacted samples were then produced by combining the pitch-catch probe with a portable manual scanner known as the Generic Scanner ("GenScan"). The signal amplitude of pitch-catch C-scan images was also correlated to the volume percent of porosity in carbon composite laminates. Finally, a simulation was performed with the numerical Wave-2000 Code for predicting the ultrasonic wave in the sample.

  10. A one-sided Jacobi algorithm for computing the singular value decomposition on a vector computer

    SciTech Connect

    De Rijk, P.P.M. )

    1989-03-01

    An old algorithm for computing the singular value decomposition, which was first mentioned by Hestenes has gained renewed interest because of its properties of parallelism and vectorizability. Some computational modifications are given and a comparison with the well-known Golub-Reinsch algorithm is made. In this paper comparative experiments on CYBER 205 are reported.

  11. Blood irradiation: Rationale and technique

    SciTech Connect

    Lewis, M.C. )

    1990-01-01

    Upon request by the local American Red Cross, the Savannah Regional Center for Cancer Care irradiates whole blood or blood components to prevent post-transfusion graft-versus-host reaction in patients who have severely depressed immune systems. The rationale for blood irradiation, the total absorbed dose, the type of patients who require irradiated blood, and the regulations that apply to irradiated blood are presented. A method of irradiating blood using a linear accelerator is described.

  12. FOOD IRRADIATION REACTOR

    DOEpatents

    Leyse, C.F.; Putnam, G.E.

    1961-05-01

    An irradiation apparatus is described. It comprises a pressure vessel, a neutronic reactor active portion having a substantially greater height than diameter in the pressure vessel, an annular tank surrounding and spaced from the pressure vessel containing an aqueous indium/sup 1//sup 1//sup 5/ sulfate solution of approximately 600 grams per liter concentration, means for circulating separate coolants through the active portion and the space between the annular tank and the pressure vessel, radiator means adapted to receive the materials to be irradiated, and means for flowing the indium/sup 1//sup 1//sup 5/ sulfate solution through the radiator means.

  13. Update on meat irradiation

    SciTech Connect

    Olson, D.G.

    1997-12-01

    The irradiation of meat and poultry in the United States is intended to eliminate pathogenic bacteria from raw product, preferably after packaging to prevent recontamination. Irradiation will also increase the shelf life of raw meat and poultry products approximately two to three times the normal shelf life. Current clearances in the United States are for poultry (fresh or frozen) at doses from 1.5 to 3.0 kGy and for fresh pork at doses from 0.3 to 1.0 kGy. A petition for the clearance of all red meat was submitted to the Food and Drug Administration (FDA) in July 1994. The petition is for clearances of fresh meat at doses from 1.5 to 4.5 kGy and for frozen meat at {approximately}2.5 to 7.5 kGy. Clearance for red meat is expected before the end of 1997. There are 28 countries that have food irradiation clearances, of which 18 countries have clearances for meat or poultry. However, there are no uniform categories or approved doses for meat and poultry among the countries that could hamper international trade of irradiated meat and poultry.

  14. Irradiating insect pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is a non-technical article focusing on phytosanitary uses of irradiation. In a series of interview questions, I present information on the scope of the invasive species problem and the contribution of international trade in agricultural products to the movement of invasive insects. This is foll...

  15. Phytosanitary applications of irradiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytosanitary treatments are used to disinfest agricultural commodities of quarantine pests so the commodities can be shipped across quarantine barriers to trade. Ionizing irradiation is a promising treatment that is increasing in use. Almost 19,000 tons of sweet potatoes and several fruits, plus ...

  16. Generic phytosanitary irradiation treatments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The history of the development of generic phytosanitary irradiation (PI) treatments is discussed beginning with its initial proposal in 1986. Generic PI treatments in use today are 150 Gy for all hosts of Tephritidae, 250 Gy for all arthropods on mango and papaya shipped from Australia to New Zeala...

  17. NSUF Irradiated Materials Library

    SciTech Connect

    Cole, James Irvin

    2015-09-01

    The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs that are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.

  18. ELECTRON IRRADIATION OF SOLIDS

    DOEpatents

    Damask, A.C.

    1959-11-01

    A method is presented for altering physical properties of certain solids, such as enhancing the usefulness of solids, in which atomic interchange occurs through a vacancy mechanism, electron irradiation, and temperature control. In a centain class of metals, alloys, and semiconductors, diffusion or displacement of atoms occurs through a vacancy mechanism, i.e., an atom can only move when there exists a vacant atomic or lattice site in an adjacent position. In the process of the invention highenergy electron irradiation produces additional vacancies in a solid over those normally occurring at a given temperature and allows diffusion of the component atoms of the solid to proceed at temperatures at which it would not occur under thermal means alone in any reasonable length of time. The invention offers a precise way to increase the number of vacancies and thereby, to a controlled degree, change the physical properties of some materials, such as resistivity or hardness.

  19. Irradiation direction from texture

    NASA Astrophysics Data System (ADS)

    Koenderink, Jan J.; Pont, Sylvia C.

    2003-10-01

    We present a theory of image texture resulting from the shading of corrugated (three-dimensional textured) surfaces, Lambertian on the micro scale, in the domain of geometrical optics. The derivation applies to isotropic Gaussian random surfaces, under collimated illumination, in normal view. The theory predicts the structure tensors from either the gradient or the Hessian of the image intensity and allows inferences of the direction of irradiation of the surface. Although the assumptions appear prima facie rather restrictive, even for surfaces that are not at all Gaussian, with the bidirectional reflectance distribution function far from Lambertian and vignetting and multiple scattering present, we empirically recover the direction of irradiation with an accuracy of a few degrees.

  20. BIOLOGICAL IRRADIATION FACILITY

    DOEpatents

    McCorkle, W.H.; Cern, H.S.

    1962-04-24

    A facility for irradiating biological specimens with neutrons is described. It includes a reactor wherein the core is off center in a reflector. A high-exposure room is located outside the reactor on the side nearest the core while a low-exposure room is located on the opposite side. Means for converting thermal neutrons to fast neutrons are movably disposed between the reactor core and the high and low-exposure rooms. (AEC)

  1. Post-irradiation effects in polyethylenes irradiated under various atmospheres

    NASA Astrophysics Data System (ADS)

    Suljovrujic, E.

    2013-08-01

    If a large amount of polymer free radicals remain trapped after irradiation of polymers, the post-irradiation effects may result in a significant alteration of physical properties during long-term shelf storage and use. In the case of polyethylenes (PEs) some failures are attributed to the post-irradiation oxidative degradation initiated by the reaction of residual free radicals (mainly trapped in crystal phase) with oxygen. Oxidation products such as carbonyl groups act as deep traps and introduce changes in carrier mobility and significant deterioration in the PEs electrical insulating properties. The post-irradiation behaviour of three different PEs, low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and high density polyethylene (HDPE) was studied; previously, the post-irradiation behaviour of the PEs was investigated after the irradiation in air (Suljovrujic, 2010). In this paper, in order to investigate the influence of different irradiation media on the post-irradiation behaviour, the samples were irradiated in air and nitrogen gas, to an absorbed dose of 300 kGy. The annealing treatment of irradiated PEs, which can substantially reduce the concentration of free radicals, is used in this study, too. Dielectric relaxation behaviour is related to the difference in the initial structure of PEs (such as branching, crystallinity etc.), to the changes induced by irradiation in different media and to the post-irradiation changes induced by storage of the samples in air. Electron spin resonance (ESR), differential scanning calorimetry (DSC), infra-red (IR) spectroscopy and gel measurements were used to determine the changes in the free radical concentration, crystal fraction, oxidation and degree of network formation, respectively.

  2. Craniospinal irradiation techniques

    NASA Astrophysics Data System (ADS)

    Scarlatescu, Ioana; Virag, Vasile; Avram, Calin N.

    2015-12-01

    In this paper we present one treatment plan for irradiation cases which involve a complex technique with multiple beams, using the 3D conformational technique. As the main purpose of radiotherapy is to administrate a precise dose into the tumor volume and protect as much as possible all the healthy tissues around it, for a case diagnosed with a primitive neuro ectoderm tumor, we have developed a new treatment plan, by controlling one of the two adjacent fields used at spinal field, in a way that avoids the fields superposition. Therefore, the risk of overdose is reduced by eliminating the field divergence.

  3. Craniospinal irradiation techniques

    SciTech Connect

    Scarlatescu, Ioana Avram, Calin N.; Virag, Vasile

    2015-12-07

    In this paper we present one treatment plan for irradiation cases which involve a complex technique with multiple beams, using the 3D conformational technique. As the main purpose of radiotherapy is to administrate a precise dose into the tumor volume and protect as much as possible all the healthy tissues around it, for a case diagnosed with a primitive neuro ectoderm tumor, we have developed a new treatment plan, by controlling one of the two adjacent fields used at spinal field, in a way that avoids the fields superposition. Therefore, the risk of overdose is reduced by eliminating the field divergence.

  4. Irradiation of northwest agricultural products

    NASA Astrophysics Data System (ADS)

    Eakin, D. E.; Tingey, G. I.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  5. Food irradiation and sterilization

    NASA Astrophysics Data System (ADS)

    Josephson, Edward S.

    Radiation sterilization of food (radappertization) requires exposing food in sealed containers to ionizing radiation at absorbed doses high enough (25-70 kGy) to kill all organisms of food spoilage and public health significance. Radappertization is analogous to thermal canning is achieving shelf stability (long term storage without refrigeration). Except for dry products in which autolysis is negligible, the radappertization process also requires that the food be heated to an internal temperature of 70-80°C (bacon to 53°C) to inactivate autolytic enzymes which catalyze spoilage during storage without refrigeration. To minimize the occurence of irradiation induced off-flavors and odors, undesirable color changes, and textural and nutritional losses from exposure to the high doses required for radappertization, the foods are vacuum sealed and irradiated frozen (-40°C to -20°C). Radappertozed foods have the characteristic of fresh foods prepared for eating. Radappertization can substitute in whole or in part for some chemical food additives such as ethylene oxide and nitrites which are either toxic, carcinogenic, mutagenic, or teratogenic. After 27 years of testing for "wholesomeness" (safety for consumption) of radappertized foods, no confirmed evidence has been obtained of any adverse effecys of radappertization on the "wholesomeness" characteristics of these foods.

  6. Consumer acceptance of irradiated poultry.

    PubMed

    Hashim, I B; Resurreccion, A V; McWatters, K H

    1995-08-01

    A simulated supermarket setting (SSS) test was conducted to determine whether consumers (n = 126) would purchase irradiated poultry products, and the effects of marketing strategies on consumer purchase of irradiated poultry products. Consumer preference for irradiated poultry was likewise determined using a home-use test. A slide program was the most effective educational strategy in changing consumers' purchase behavior. The number of participants who purchased irradiated boneless, skinless breasts and irradiated thighs after the educational program increased significantly from 59.5 and 61.9% to 83.3 and 85.7% for the breasts and thighs, respectively. Using a label or poster did not increase the number of participants who bought irradiated poultry products. About 84% of the participants consider it either "somewhat necessary" or "very necessary" to irradiate raw chicken and would like all chicken that was served in restaurants or fast food places to be irradiated. Fifty-eight percent of the participants would always buy irradiated chicken if available, and an additional 27% would buy it sometimes. About 44% of the participants were willing to pay the same price for irradiated chicken as for nonirradiated. About 42% of participants were willing to pay 5% or more than what they were currently paying for nonirradiated chicken. Seventy-three percent or more of consumers who participated in the home-use test (n = 74) gave the color, appearance, and aroma of the raw poultry products a minimum rating of 7 (= like moderately). After consumers participated in a home-use test, 84 and 88% selected irradiated thighs and breasts, respectively, over nonirradiated in a second SSS test. PMID:7479506

  7. Microvascular anastomoses in irradiated vessels: A comparison between the Unilink system and sutures

    SciTech Connect

    Ragnarsson, R.; Berggren, A.; Klintenberg, C.; Ostrup, L. )

    1990-03-01

    A new mechanical device (the Unilink system) was compared to conventional suture anastomoses in irradiated microvessels. Twenty rabbits received a single radiation dose of 20 Gy from a 7-MeV electron source through an anterior neck field. One and 6 months following irradiation, the carotid arteries and facial veins were divided and anastomosed on one side with the Unilink system and on the other side with suture technique. At sacrifice 4 weeks postoperatively, all vessels were evaluated for patency and histologic changes associated with radiation and anastomotic trauma. Histology disclosed severe radiation changes. Also, intimal hyperplasia was consistently found at the anastomotic sites in the arteries, while it was totally absent in the venous anastomoses. Occlusive thrombosis was found in two arteries, one anastomosed with the Unilink system and one sutured. Two other arteries, one from each group, had subtotal occlusions at the anastomotic site. No occlusions occurred in any of the venous anastomoses. The overall patency in this study was 97.5 percent, with no difference between the two techniques.

  8. Food Irradiation for Produce Safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A research priority for the produce industry is the development of an effective, safe and commercially applicable kill step. Irradiation is a nonthermal process that has been shown to inactivate human pathogens from fruits and vegetables. Irradiation treatment at 1.0 kGy can reduce the surface popul...

  9. Phytosanitary irradiation in south Asia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation has the potential to solve phytosanitary problems related to trade in south Asia. In general, it is the phytosanitary treatment most tolerated by fresh agricultural commodities. Irradiation technology is available in some countries of the region but is only used for phytosanitary purpos...

  10. Commercial implementation of food irradiation

    NASA Astrophysics Data System (ADS)

    Welt, M. A.

    In July 1981, the first specifically designed multi-purpose irradiation facility for food irradiation was put into service by the Radiation Technology, Inc. subsidiary Process Technology, Inc. in West Memphis, Arkansas. The operational experience gained, resulted in an enhanced design which was put into commercial service in Haw River, North Carolina, by another subsidiary, Process Technology (N.C.), Inc. in October 1983. These facilities have enabled the food industry to assess the commercial viability of food irradiation. Further impetus towards commercialization of food irradiation was gained in March 1981 with the filing in the Federal Register, by the FDA, of an Advanced Proposed Notice of Rulemaking for Food Irradiation. Two years later in July 1983, the FDA approved the first food additive regulation involving food irradiation in nineteen years, when they approved the Radiation Technology, Inc. petition calling for the sanitization of spices, onion powder and garlic powder at a maximum dosage of 10 kGy. Since obtaining the spice irradiation approval, the FDA has accepted four additional petitions for filing in the Federal Register. One of the petitions which extended spice irradiation to include insect disinfestation has issued into a regulation while the remaining petitions covering the sanitization of herbs, spice blends, vegetable seasonings and dry powdery enzymes as well as the petition to irradiate hog carcasses and pork products for trichinae control at 1 kGy, are expected to issue either before the end of 1984 or early in 1985. More recently, food irradiation advocates in the United States received another vote of confidence by the announcement that a joint venture food irradiation facility to be constructed in Hawaii by Radiation Technology, is backed by a contractual committment for the processing of 40 million pounds of produce per year. Another step was taken when the Port of Salem, New Jersey announced that the Radiation Technology Model RT-4104

  11. Pallet irradiators for food processing

    NASA Astrophysics Data System (ADS)

    McKinnon, R. G.; Chu, R. D. H.

    This paper looks at the various design concepts for the irradiation processing of food products, with particular emphasis on handling the products on pallets. Pallets appear to offer the most attractive method for handling foods from many considerations. Products are transported on pallets. Warehouse space is commonly designed for pallet storage and, if products are already palletized before and after irradiation, then labour could be saved by irradiating on pallets. This is also an advantage for equipment operation since a larger carrier volume means lower operation speeds. Different pallet irradiator design concepts are examined and their suitability for several applications are discussed. For example, low product holdup for fast turn around will be a consideration for those operating an irradiation "service" business; others may require a very large source where efficiency is the primary requirement and this will not be consistent with low holdup. The radiation performance characteristics and processing costs of these machines are discussed.

  12. Nanoindentation on ion irradiated steels

    NASA Astrophysics Data System (ADS)

    Hosemann, P.; Vieh, C.; Greco, R. R.; Kabra, S.; Valdez, J. A.; Cappiello, M. J.; Maloy, S. A.

    2009-06-01

    Radiation induced mechanical property changes can cause major difficulties in designing systems operating in a radiation environment. Investigating these mechanical property changes in an irradiation environment is a costly and time consuming activity. Ion beam accelerator experiments have the advantage of allowing relatively fast and inexpensive materials irradiations without activating the sample but do in general not allow large beam penetration depth into the sample. In this study, the ferritic/martensitic steel HT-9 was processed and heat treated to produce one specimen with a large grained ferritic microstructure and further heat treated to form a second specimen with a fine tempered martensitic lath structure and exposed to an ion beam and tested after irradiation using nanoindentation to investigate the irradiation induced changes in mechanical properties. It is shown that the HT-9 in the ferritic heat treatment is more susceptible to irradiation hardening than HT-9 after the tempered martensitic heat treatment. Also at an irradiation temperature above 550 °C no detectable hardness increase due to irradiation was detected. The results are also compared to data from the literature gained from the fast flux test facility.

  13. New facility for post irradiation examination of neutron irradiated beryllium

    SciTech Connect

    Ishitsuka, Etsuo; Kawamura, Hiroshi

    1995-09-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800{degrees}C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and {sup 60}Co;7.4 MBq/day.

  14. AFIP-4 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

    2012-01-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE)1,2. The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  15. AFIP-4 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; Misti A Lillo; Gray S. Chang; Glenn A Roth; Nicolas Woolstenhulme; Daniel M Wachs

    2011-09-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-4 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of research reactor fuel plates. The AFIP-4 test further examine the fuel/clad interface and its behavior under extreme conditions. After irradiation, fission gas retention measurements will be performed during post irradiation (PIE). The following report summarizes the life of the AFIP-4 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  16. Therapeutic postprostatectomy irradiation.

    PubMed

    Youssef, Emad; Forman, Jeffrey D; Tekyi-Mensah, Samuel; Bolton, Susan; Hart, Kim

    2002-06-01

    The purpose of this study was to determine the outcome of patients receiving external beam radiation for an elevated postprostatectomy prostate-specific antigen (PSA) level. Between December 1991 and September 1998, 108 patients received definitive radiation therapy for elevated postprostatectomy PSA levels. The median dose of irradiation was 68 Gy (range, 48-74 Gy). During treatment, the PSA levels were checked an average of 5 times (range, 3-7 times). Prostate-specific antigen values were judged to decline or increase during treatment if they changed by more than 0.2 ng/mL. After treatment, biochemical failure was defined as a measurable or rising PSA > 0.2 ng/mL. Median follow-up was 51 months (range, 3-112 months). Fifty-eight patients (54%) had evidence of biochemical failure. The 3- and 5-year actuarial biochemical relapse-free (bNED) survivals for all patients were 55% and 39%, respectively. Upon univariate analysis, intratreatment PSA and preradiation PSA were significant predictors of bNED survival. Patients with a PSA level that decreased during treatment had a 5-year bNED survival of 43% compared to 10% in patients with an increasing PSA level (P = 0.0002). Using the preradiation therapy PSA value as a continuous variable, higher preradiation therapy PSA levels were associated with an increased risk of failure (P = 0.004). Cut points of pretreatment PSA were derived at 0.9 ng/mL and 4.2 ng/mL using the Michael Leblanc recursive partitioning algorithm. The 5-year bNED rate for patients with a preradiation therapy PSA < 0.9 ng/mL was 45% versus 42% for patients with preradiation therapy PSA between 0.9 and 4.2 ng/mL and 21% for patients > or = 4.2 ng/mL (P = 0.0003). Patients with a Gleason score of < or = 7 had a 5-year bNED rate of 38% compared to 37% for patients with a Gleason score > 7 (P = 0.27). Other factors examined individually that did not reach statistical significance included time from surgery to radiation therapy, race, seminal vesicle

  17. (Irradiation creep of graphite)

    SciTech Connect

    Kennedy, C.R.

    1990-12-21

    The traveler attended the Conference, International Symposium on Carbon, to present an invited paper, Irradiation Creep of Graphite,'' and chair one of the technical sessions. There were many papers of particular interest to ORNL and HTGR technology presented by the Japanese since they do not have a particular technology embargo and are quite open in describing their work and results. In particular, a paper describing the failure of Minor's law to predict the fatigue life of graphite was presented. Although the conference had an international flavor, it was dominated by the Japanese. This was primarily a result of geography; however, the work presented by the Japanese illustrated an internal program that is very comprehensive. This conference, a result of this program, was better than all other carbon conferences attended by the traveler. This conference emphasizes the need for US participation in international conferences in order to stay abreast of the rapidly expanding HTGR and graphite technology throughout the world. The United States is no longer a leader in some emerging technologies. The traveler was surprised by the Japanese position in their HTGR development. Their reactor is licensed and the major problem in their graphite program is how to eliminate it with the least perturbation now that most of the work has been done.

  18. Generic phytosanitary irradiation treatments

    NASA Astrophysics Data System (ADS)

    Hallman, Guy J.

    2012-07-01

    The history of the development of generic phytosanitary irradiation (PI) treatments is discussed beginning with its initial proposal in 1986. Generic PI treatments in use today are 150 Gy for all hosts of Tephritidae, 250 Gy for all arthropods on mango and papaya shipped from Australia to New Zealand, 300 Gy for all arthropods on mango shipped from Australia to Malaysia, 350 Gy for all arthropods on lychee shipped from Australia to New Zealand and 400 Gy for all hosts of insects other than pupae and adult Lepidoptera shipped to the United States. Efforts to develop additional generic PI treatments and reduce the dose for the 400 Gy treatment are ongoing with a broad based 5-year, 12-nation cooperative research project coordinated by the joint Food and Agricultural Organization/International Atomic Energy Agency Program on Nuclear Techniques in Food and Agriculture. Key groups identified for further development of generic PI treatments are Lepidoptera (eggs and larvae), mealybugs and scale insects. A dose of 250 Gy may suffice for these three groups plus others, such as thrips, weevils and whiteflies.

  19. Irradiation pretreatment for coal desulfurization

    NASA Technical Reports Server (NTRS)

    Hsu, G. C.

    1979-01-01

    Process using highly-penetrating nuclear radiation (Beta and Gamma radiation) from nuclear power plant radioactive waste to irradiate coal prior to conventional desulfurization procedures increases total extraction of sulfur.

  20. Irradiation of Northwest agricultural products

    SciTech Connect

    Eakin, D.E.; Tingey, G.L.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect control procedures are developed and followed. Due to the recognized potential benefits of irradiation, Pacific Northwest Laboratory (PNL) is conducting this program to evaluate the benefits of using irradiation on Northwest agricultural products under the US Department of Energy (DOE) Defense Byproducts Production and Utilization Program. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  1. Consumer attitudes toward irradiated food

    SciTech Connect

    Conley, S.

    1994-12-31

    Throughout history, new methods of food preservation have been met with skepticism and fear. Such processes as pasteurization and canning were denounced as being dangerous, detrimental to nutrients, or an excuse for dirty products. Now comes irradiation, and activists argue against this new process for the same reasons. Publicly, the perception is that consumers, distrustful of nuclear power, will never buy or accept irradiated food.

  2. Slag recycling of irradiated vanadium

    SciTech Connect

    Gorman, P.K.

    1995-04-05

    An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were carried out to determine if the slag did indeed remove the transmutation impurities from the irradiated vanadium.

  3. Irradiation Induced Creep of Graphite

    SciTech Connect

    Burchell, Timothy D; Murty, Prof K.L.; Eapen, Dr. Jacob

    2010-01-01

    The current status of graphite irradiation induced creep strain prediction is reviewed and the major creep models are described. The ability of the models to quantitatively predict the irradiation induced creep strain of graphite is reported. Potential mechanisms of in-crystal creep are reviewed as are mechanisms of pore generation under stress. The case for further experimental work is made and the need for improved creep models across multi-scales is highlighted.

  4. Calculating Irradiance For Photosynthesis In The Ocean

    NASA Technical Reports Server (NTRS)

    Collins, Donald J.; Davis, Curtiss O.; Booth, C. Rockwell; Kiefer, Dale A.; Stallings, Casson

    1990-01-01

    Mathematical model predicts available and usable irradiances. Yields estimates of irradiance available for photosynthesis (Epar) and irradiance usable for photosynthesis (Epur) as functions of depth in ocean. Describes Epur and Epar in terms of spectral parameters measured remotely (from satellites or airplanes). These irradiances useful in studies of photosynthetic productivity of phytoplankton in euphotic layer.

  5. Cancer following medical irradiation.

    PubMed

    Boice, J D

    1981-03-01

    Several generalizations about radiation carcinogenesis can be made: 1) a single exposure is sufficient to elevate cancer incidence many years later: 2) radiation-induced cancer cannot be distinguished from naturally occurring cancer, i.e., there is not unique radiogenic cancer; 3) all cancers appear to be increased after irradiation with the exception of chronic lymphocytic leukemia, and possibly Hodgkin's disease, cervical cancer, and a few others; 4) the breast, thyroid, and bone marrow appear especially radiosensitive; 5) leukemia is the most prominent radiogenic tumor and shows a wave-like pattern of excess incidence over time, and the excess begins within two to four years, peaks about six to eight years, and decreases to normal levels about 25 years later; 6) solid tumors have a minimum latent period of about ten years, and for several cancers, the temporal pattern of incidence appears to follow the natural incidence, i.e., the cancers do not occur before the ages normally associated with increased incidence, implying that age-dependent factors influence the expression of disease; 7) age at exposure is perhaps the most important host factor influencing subsequent cancer risk; 8) the percentage increase in cancer incidence per rad is not the same for all cancers, i.e., some cancer of high natural incidence, e.g., colon, have low "relative risks" and some cancers of low natural incidence, e.g., thyroid, have high "relative risks;" 9) dose-effect curves are often linear, but curvilinearity is also observed and is possibly associated with the need for "two ionizing events" for transformation to occur at low doses, the influence of cell sterilization at moderate doses, the likelihood of "wasted" dose at high doses, and/or the influence of factors that effect the expression of disease. PMID:7237365

  6. Cancer following medical irradiation

    SciTech Connect

    Boice, J.D.

    1981-03-01

    Several generalizations about radiation carcinogenesis can be made: 1) a single exposure is sufficient to elevate cancer incidence many years later: 2) radiation-induced cancer cannot be distinguished from naturally occurring cancer, i.e., there is not unique radiogenic cancer; 3) all cancers appear to be increased after irradiation with the exception of chronic lymphocytic leukemia, and possibly Hodgkin's disease, cervical cancer, and a few others; 4) the breast, thyroid, and bone marrow appear especially radiosensitive; 5) leukemia is the most prominent radiogenic tumor and shows a wave-like pattern of excess incidence over time, and the excess begins within two to four years, peaks about six to eight years, and decreases to normal levels about 25 years later; 6) solid tumors have a minimum latent period of about ten years, and for several cancers, the temporal pattern of incidence appears to follow the natural incidence, i.e., the cancers do not occur before the ages normally associated with increased incidence, implying that age-dependent factors influence the expression of disease; 7) age at exposure is perhaps the most important host factor influencing subsequent cancer risk; 8) the percentage increase in cancer incidence per rad is not the same for all cancers, i.e., some cancer of high natural incidence, e.g., colon, have low ''relative risks'' and some cancers of low natural incidence, e.g., thyroid, have high ''relative risks;'' 9) dose-effect curves are often linear, but curvilinearity is also observed and is possibly associated with the need for ''two ionizing events'' for transformation to occur at low doses, the influence of cell sterilization at moderate doses, the likelihood of ''wasted'' dose at high doses, and/or the influence of factors that effect the expression of disease.

  7. Cancer following medical irradiation

    SciTech Connect

    Boice, J.D.

    1981-03-01

    Several generalizations about radiation carcinogenesis can be made: (1) a single exposure is sufficient to elevate cancer incidence many years later; (2) radiation-induced cancer cannot be distinguished from naturally occurring cancer, i.e., there is no unique radiogenic cancer; (3) all cancers appear to be increased after irradiation with the exception of chronic lymphocytic leukemia, and possibly Hodgkin's disease, cervical cancer, and a few others; (4) the breast, thyroid, and bone marrow appear especially radiosensitive; (5) leukemia is the most prominent radiogenic tumor and shows a wave-like pattern of excess incidence over time, and the excess begins within two to four years, peaks about six to eight years, and decreases to normal levels about 25 years later; (6) solid tumors have a minimum latent period of about ten years, and for several cancers, the temporal pattern of incidence appears to follow the natural incidence, i.e., the cancers do not occur before the ages normally associated with increased incidence, implying that age-dependent factors influence the expression of disease; (7) age at exposure is perhaps the most important host factor influencing subsequent cancer risk; (8) the percentage increase in cancer incidence per rad is not the same for all cancers, i.e., some cancers of high natural incidence, e.g., colon, have low relative risks and some cancers of low natural incidence, e.g., thyroid, have high relative risks; (9) dose-effect curves are often linear, but curvilinearity is also observed and is possibly associated with the need for two ionizing events for transformation to occur at low doses, the influence of cell sterilization at moderate doses, the likelihood of wasted dose at high doses, and/or the influence of factors that effect the expression of disease.

  8. Food irradiation: Public opinion surveys

    SciTech Connect

    Kerr, S.D.

    1987-01-01

    The Canadian government are discussing the legislation, regulations and practical protocol necessary for the commercialization of food irradiation. Food industry marketing, public relations and media expertise will be needed to successfully introduce this new processing choice to retailers and consumers. Consumer research to date including consumer opinion studies and market trials conducted in the Netherlands, United States, South Africa and Canada will be explored for signposts to successful approaches to the introduction of irradiated foods to retailers and consumers. Research has indicated that the terms used to describe irradiation and information designed to reduce consumer fears will be important marketing tools. Marketers will be challenged to promote old foods, which look the same to consumers, in a new light. Simple like or dislike or intention to buy surveys will not be effective tools. Consumer fears must be identified and effectively handled to support a receptive climate for irradiated food products. A cooperative government, industry, health professional, consumer association and retailer effort will be necessary for the successful introduction of irradiated foods into the marketplace. Grocery Products Manufacturers of Canada is a national trade association of more than 150 major companies engaged in the manufacture of food, non-alcoholic beverages and array of other national-brand consumer items sold through retail outlets.

  9. Elective ilioingunial lymph node irradiation

    SciTech Connect

    Henderson, R.H.; Parsons, J.T.; Morgan, L.; Million, R.R.

    1984-06-01

    Most radiologists accept that modest doses of irradiation (4500-5000 rad/4 1/2-5 weeks) can control subclinical regional lymph node metastases from squamous cell carcinomas of the head and neck and adenocarcinomas of the breast. There have been few reports concerning elective irradiation of the ilioinguinal region. Between October 1964 and March 1980, 91 patients whose primary cancers placed the ilioinguinal lymph nodes at risk received elective irradiation at the University of Florida. Included are patients with cancers of the vulva, penis, urethra, anus and lower anal canal, and cervix or vaginal cancers that involved the distal one-third of the vagina. In 81 patients, both inguinal areas were clinically negative; in 10 patients, one inguinal area was positive and the other negative by clinical examination. The single significant complication was a bilateral femoral neck fracture. The inguinal areas of four patients developed mild to moderate fibrosis. One patient with moderate fibrosis had bilateral mild leg edema that was questionably related to irradiation. Complications were dose-related. The advantages and dis-advantages of elective ilioinguinal node irradiation versus elective inguinal lymph node dissection or no elective treatment are discussed.

  10. Plasmodium falciparum: attenuation by irradiation

    SciTech Connect

    Waki, S.; Yonome, I.; Suzuki, M.

    1983-12-01

    The effect of irradiation on the in vitro growth of Plasmodium falciparum was investigated. The cultured malarial parasites at selected stages of development were exposed to gamma rays and the sensitivity of each stage was determined. The stages most sensitive to irradiation were the ring forms and the early trophozoites; late trophozoites were relatively insensitive. The greatest resistance was shown when parasites were irradiated at a time of transition from the late trophozoite and schizont stages to young ring forms. The characteristics of radiosensitive variation in the parasite cycle resembled that of mammalian cells. Growth curves of parasites exposed to doses of irradiation upto 150 gray had the same slope as nonirradiated controls but parasites which were exposed to 200 gray exhibited a growth curve which was less steep than that for parasites in other groups. Less than 10 organisms survived from the 10(6) parasites exposed to this high dose of irradiation; the possibility exists of obtaining radiation-attenuated P. falciparum.

  11. Prospects of international trade in irradiated foods

    NASA Astrophysics Data System (ADS)

    Loaharanu, P.

    Irradiation is gaining recognition as a physical process for reducing food losses, enhancing hygienic quality of food and facilitating food trade. At present, 36 countries have approved the use of irradiation for processing collectively over 40 food items either on an unconditional or restricted basis. Commercial use of irradiated foods and food ingredients is being carried out in 22 countries. Technology transfer on food irradiation is being intensified to local industry in different regions. worldwide, a total of 40 commercial/demonstration irradiators available for treating foods have been or are being constructed. Acceptance and control of international trade in irradiated foods were discussed at the International Conference on the Acceptance, Control of and Trade in Irradiated Food, jointly convened by FAO, IAEA, WHO and ITC-UNCTAD/GATT in Geneva, Switzerland, 12-16 December 1988. An "International Document on Food Irradiation" was adopted by consensus at this Conference which will facilitate wider acceptance and control of international trade in irradiated foods.

  12. In Vitro Study of Er:YAG and Er, Cr:YSGG Laser Irradiation on Human Gingival Fibroblast Cell Line.

    PubMed

    Talebi-Ardakani, Mohammad Reza; Torshabi, Maryam; Karami, Elahe; Arbabi, Elham; Rezaei Esfahrood, Zeinab

    2016-04-01

    The ultimate goal of the periodontal treatments is a regeneration of periodontium. Recently, laser irradiations are commonly used to improve wound repair. Because of many controversies about the effects of laser on soft tissue regeneration, more in vitro studies are still needed. The aim of the present in vitro study was to compare the effects of different doses of Er:YAG (erbium-doped:yttrium, aluminum, garnet) and Er, Cr:YSGG (erbium, chromium-doped: yttrium, scandium, gallium, garnet) laser treatment on human gingival fibroblasts (HGF) proliferation. In this randomized single-blind controlled in vitro trial, HGF cells were irradiated using Er:YAG and Er, Cr:YSGG laser for 10 and 30 seconds or remained unexposed as a control group. After a culture period of 24 and 48 hours, HGF cell proliferation was evaluated by MTT assay. The data were subjected to one-sided analysis of variance and Tukey multiple comparison tests. Our results showed Er:YAG application for 10 and 30 seconds as well as Er, Cr:YSGG irradiation for 10 and 30 seconds induced statistically significant (P<0.05) proliferation of HGF cells as compared with the control at 24 hours up to 18.39%, 26.22%, 21.21%, and 17.06% respectively. In 48 hour incubations, Er:YAG and Er, Cr:YSGG irradiation for 10 and 30 seconds significantly increased cellular proliferation up to 22.9%, 32.24%, 30.52% and 30.02% respectively (P<0.05). This study demonstrates that Er:YAG and Er, Cr:YSGG laser significantly increased HGF cell proliferation compared to the control specimens. This higher proliferation can lead to increased wound repair in clinical conditions. PMID:27309266

  13. Neutron irradiation of beryllium pebbles

    SciTech Connect

    Gelles, D.S.; Ermi, R.M.; Tsai, H.

    1998-03-01

    Seven subcapsules from the FFTF/MOTA 2B irradiation experiment containing 97 or 100% dense sintered beryllium cylindrical specimens in depleted lithium have been opened and the specimens retrieved for postirradiation examination. Irradiation conditions included 370 C to 1.6 {times} 10{sup 22} n/cm{sup 2}, 425 C to 4.8 {times} 10{sup 22} n/cm{sup 2}, and 550 C to 5.0 {times} 10{sup 22} n/cm{sup 2}. TEM specimens contained in these capsules were also retrieved, but many were broken. Density measurements of the cylindrical specimens showed as much as 1.59% swelling following irradiation at 500 C in 100% dense beryllium. Beryllium at 97% density generally gave slightly lower swelling values.

  14. Investigation of irradiated soil byproducts.

    PubMed

    Brey, R R; Rodriguez, R; Harmon, J F; Winston, P

    2001-01-01

    The high dose irradiation of windblown soil deposited onto the surface of spent nuclear fuel is of concern to long-term fuel storage stability. Such soils could be exposed to radiation fields as great as 1.08 x 10(-3) C/kg-s (15,000 R/hr) during the 40-year anticipated period of interim dry storage prior to placement at the proposed national repository. The total absorbed dose in these cases could be as high as 5 x 10(7) Gy (5 x 10(9) rads). This investigation evaluated the potential generation of explosive or combustible irradiation byproducts during this irradiation. It focuses on the production of radiolytic byproducts generated within the pore water of surrogate clays that are consistent with those found on the Idaho National Engineering and Environmental Laboratory. Synthesized surrogates of localized soils containing combinations of clay, water, and aluminum samples, enclosed within a stainless steel vessel were irradiated and the quantities of the byproducts generated measured. Two types of clays, varying primarily in the presence of iron oxide, were investigated. Two treatment levels of irradiation and a control were investigated. An 18-Mev linear accelerator was used to irradiate samples. The first irradiation level provided an absorbed dose of 3.9 x 10(5)+/-1.4 x 10(5)Gy (3.9 x 10(7)+/-1.4 x 10(7) rads) in a 3-h period. At the second irradiation level, 4.8 x 10(5)+/-2.0 x 10(5)Gy (4.8 x 10(7)+/-2.0 x 10(7) rads) were delivered in a 6-h period. When averaged over all treatment parameters, irradiated clay samples with and without iron (III) oxide (moisture content = 40%) had a production rate of hydrogen gas that was a strong function of radiation-dose. A g-value of 5.61 x 10(-9)+/-1.56 x 10(-9) mol/J (0.054+/-0.015 molecules/100-eV) per mass of pore water was observed in the clay samples without iron (III) oxide for hydrogen gas production. A g-value of 1.07 x 10(-8)+/-2.91 x 10(-9) mol/J (0.103+0.028 molecules/100-eV) per mass of pore water was observed

  15. Experimental investigation on the heat transfer characteristics and flow pattern in vertical narrow channels heated from one side

    NASA Astrophysics Data System (ADS)

    Huang, Lihao; Li, Gang; Tao, Leren

    2016-07-01

    Experimental investigation for the flow boiling of water in a vertical rectangular channel was conducted to reveal the boiling heat transfer mechanism and flow patterns map aspects. The onset of nucleate boiling went upward with the increasing of the working fluid mass flow rate or the decreasing of the inlet working fluid temperature. As the vapour quality was increased, the local heat transfer coefficient increased first, then decreased, followed by various flow patterns. The test data from other researchers had a similar pattern transition for the bubble-slug flow and the slug-annular flow. Flow pattern transition model analysis was performed to make the comparison with current test data. The slug-annular and churn-annular transition models showed a close trend with current data except that the vapor phase superficial velocity of flow pattern transition was much higher than that of experimental data.

  16. Inclusion probability for DNA mixtures is a subjective one-sided match statistic unrelated to identification information

    PubMed Central

    Perlin, Mark William

    2015-01-01

    Background: DNA mixtures of two or more people are a common type of forensic crime scene evidence. A match statistic that connects the evidence to a criminal defendant is usually needed for court. Jurors rely on this strength of match to help decide guilt or innocence. However, the reliability of unsophisticated match statistics for DNA mixtures has been questioned. Materials and Methods: The most prevalent match statistic for DNA mixtures is the combined probability of inclusion (CPI), used by crime labs for over 15 years. When testing 13 short tandem repeat (STR) genetic loci, the CPI-1 value is typically around a million, regardless of DNA mixture composition. However, actual identification information, as measured by a likelihood ratio (LR), spans a much broader range. This study examined probability of inclusion (PI) mixture statistics for 517 locus experiments drawn from 16 reported cases and compared them with LR locus information calculated independently on the same data. The log(PI-1) values were examined and compared with corresponding log(LR) values. Results: The LR and CPI methods were compared in case examples of false inclusion, false exclusion, a homicide, and criminal justice outcomes. Statistical analysis of crime laboratory STR data shows that inclusion match statistics exhibit a truncated normal distribution having zero center, with little correlation to actual identification information. By the law of large numbers (LLN), CPI-1 increases with the number of tested genetic loci, regardless of DNA mixture composition or match information. These statistical findings explain why CPI is relatively constant, with implications for DNA policy, criminal justice, cost of crime, and crime prevention. Conclusions: Forensic crime laboratories have generated CPI statistics on hundreds of thousands of DNA mixture evidence items. However, this commonly used match statistic behaves like a random generator of inclusionary values, following the LLN rather than measuring identification information. A quantitative CPI number adds little meaningful information beyond the analyst's initial qualitative assessment that a person's DNA is included in a mixture. Statistical methods for reporting on DNA mixture evidence should be scientifically validated before they are relied upon by criminal justice. PMID:26605124

  17. Healing in the irradiated wound

    SciTech Connect

    Miller, S.H.; Rudolph, R. )

    1990-07-01

    Poor or nonhealing of irradiated wounds has been attributed to progressive obliterative endarteritis. Permanently damaged fibroblasts may also play an important part in poor healing. Regardless of the cause, the key to management of irradiated skin is careful attention to prevent its breakdown and conservative, but adequate, treatment when wounds are minor. When wounds become larger and are painful, complete excision of the wound or ulcer is called for and coverage should be provided by a well-vascularized nonparasitic distant flap.16 references.

  18. Irradiated icecreams for immunosuppressed patients

    NASA Astrophysics Data System (ADS)

    Adeil Pietranera, M. S.; Narvaiz, P.; Horak, C.; Kairiyama, E.

    2003-04-01

    Vanilla, raspberry, peach and milk jam icecreams were gamma irradiated with 3, 6 and 9 kGy doses in order to achieve microbial decontamination. Microbiological, sensory and some chemical analysis (acidity, peroxides, ultraviolet and visible absorption, thin-layer chromatography and sugar determination) were performed. Water-based icecreams (raspberry and peach) were more resistant to gamma radiation than cream-based ones (vanilla and milk jam). Gamma irradiation with 3 kGy reduced remarkably the microbial load of these icecreams without impairing the quality of the icecreams.

  19. Modeling Solar Lyman Alpha Irradiance

    NASA Technical Reports Server (NTRS)

    Pap, J.; Hudson, H. S.; Rottman, G. J.; Willson, R. C.; Donnelly, R. F.; London, J.

    1990-01-01

    Solar Lyman alpha irradiance is estimated from various solar indices using linear regression analyses. Models developed with multiple linear regression analysis, including daily values and 81-day running means of solar indices, predict reasonably well both the short- and long-term variations observed in Lyman alpha. It is shown that the full disk equivalent width of the He line at 1083 nm offers the best proxy for Lyman alpha, and that the total irradiance corrected for sunspot effect also has a high correlation with Lyman alpha.

  20. Solar Irradiance: Observations, Proxies, and Models (Invited)

    NASA Astrophysics Data System (ADS)

    Lean, J.

    2013-12-01

    Solar irradiance has been measured from space for more than thirty years. Variations in total (spectrally integrated) solar irradiance associated with the Sun's 11-year activity cycle and 27-day rotation are now well characterized. But the magnitude, and even the sign, of spectral irradiance changes at near ultraviolet, visible and near infrared wavelengths, remain uncertain on time scales longer than a few months. Drifts in the calibration of the instruments that measure solar irradiance and incomplete understanding of the causes of irradiance variations preclude specification of multi-decadal solar irradiance variations with any confidence, including whether, or not, irradiance levels were lower during the 2008-2009 anomalously low solar activity minimum than in prior minima. The ultimate cause of solar irradiance variations is the Sun's changing activity, driven by a sub-surface dynamo that generates magnetic features called sunspots and faculae, which respectively deplete and enhance the net radiative output. Solar activity also alters parameters that have been measured from the ground for longer periods and with greater stability than the solar irradiance datasets. The longest and most stable such record is the Sun's irradiance at 10.7 cm in the radio spectrum, which is used frequently as a proxy indicator of solar irradiance variability. Models have been developed that relate the solar irradiance changes - both total and spectral - evident in extant databases to proxies chosen to best represent the sunspot darkening and facular brightening influences. The proxy models are then used to reconstruct solar irradiance variations at all wavelengths on multi-decadal time scales, for input to climate and atmospheric model simulations that seek to quantity the Sun's contribution to Earth's changing environment. This talk provides an overview of solar total and spectral irradiance observations and their relevant proxies, describes the formulation and construction of

  1. Studying Solar Irradiance Variability with Wavelet Technique

    NASA Technical Reports Server (NTRS)

    Vigouroux, Anne; Pap, Judit

    1995-01-01

    The detection of variations in solar irradiance by satellite-based experiments during the last 17 years stimulated modelling efforts to help to identify their causes and to provide estimates for irradiance data when no satellite observations exist.

  2. Feasibilty of exterior vascular laser irradiation therapy

    NASA Astrophysics Data System (ADS)

    Chen, Rong; Xie, Shusen; Li, Hui; Li, Buhong; Chen, Yanjiao; Zhang, Xiaodong; Chen, Huifang; Xia, Xiangnan; Lin, Aizhen

    1998-08-01

    In order to study the exterior vascular laser irradiation therapy for replacing the intravascular laser irradiation therapy, we measure the distribution of radiant fluence rate in exterior vascular laser irradiation in vivo and imitative intravascular laser irradiation. The result shows that the average radiant fluence rate of exterior vascular and intravascular is 1.11 and 10.81 respectively, which is ten times between them. In order to get the radiant fluence rate corresponding to the intravascular laser irradiation, we suggest that about 20 mW HeNe laser could be used in exterior vascular laser irradiation therapy, and the laser must irradiate on the vascular perpendicularly. The suitable patient with exposed vascular must be chosen, and the diameter of the irradiated vascular is about 6 mm. Our experiment result, especially the data measured in vivo, will be useful for the research of light transport in human tissue.

  3. Statistical criteria for characterizing irradiance time series.

    SciTech Connect

    Stein, Joshua S.; Ellis, Abraham; Hansen, Clifford W.

    2010-10-01

    We propose and examine several statistical criteria for characterizing time series of solar irradiance. Time series of irradiance are used in analyses that seek to quantify the performance of photovoltaic (PV) power systems over time. Time series of irradiance are either measured or are simulated using models. Simulations of irradiance are often calibrated to or generated from statistics for observed irradiance and simulations are validated by comparing the simulation output to the observed irradiance. Criteria used in this comparison should derive from the context of the analyses in which the simulated irradiance is to be used. We examine three statistics that characterize time series and their use as criteria for comparing time series. We demonstrate these statistics using observed irradiance data recorded in August 2007 in Las Vegas, Nevada, and in June 2009 in Albuquerque, New Mexico.

  4. Food irradiation research and technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food Irradiation is a safe and effective U.S. Food and Drug Administration (FDA) approved process that can be used to disinfest or delay the maturation of fruits and vegetables, improve the microbiological safety of shellfish, eggs, raw meat and poultry, spices, and seeds used for sprouting. FDA ap...

  5. Food irradiation: regulations and acceptance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food irradiation is an effective technology for reducing harmful pathogens and insect pests on meats, poultry, seafood and fruits and vegetables. Although it is one of the most extensively researched nonthermal food processing technologies, its commercial adoption remains relatively limited. Regulat...

  6. Solar Spectral Irradiance and Climate

    NASA Technical Reports Server (NTRS)

    Pilewskie, P.; Woods, T.; Cahalan, R.

    2012-01-01

    Spectrally resolved solar irradiance is recognized as being increasingly important to improving our understanding of the manner in which the Sun influences climate. There is strong empirical evidence linking total solar irradiance to surface temperature trends - even though the Sun has likely made only a small contribution to the last half-century's global temperature anomaly - but the amplitudes cannot be explained by direct solar heating alone. The wavelength and height dependence of solar radiation deposition, for example, ozone absorption in the stratosphere, absorption in the ocean mixed layer, and water vapor absorption in the lower troposphere, contribute to the "top-down" and "bottom-up" mechanisms that have been proposed as possible amplifiers of the solar signal. New observations and models of solar spectral irradiance are needed to study these processes and to quantify their impacts on climate. Some of the most recent observations of solar spectral variability from the mid-ultraviolet to the near-infrared have revealed some unexpected behavior that was not anticipated prior to their measurement, based on an understanding from model reconstructions. The atmospheric response to the observed spectral variability, as quantified in climate model simulations, have revealed similarly surprising and in some cases, conflicting results. This talk will provide an overview on the state of our understanding of the spectrally resolved solar irradiance, its variability over many time scales, potential climate impacts, and finally, a discussion on what is required for improving our understanding of Sun-climate connections, including a look forward to future observations.

  7. Irradiation enhancement of biomass conversion

    NASA Astrophysics Data System (ADS)

    Smith, G. S.; Kiesling, H. E.; Galyean, M. L.; Bader, J. R.

    The vast supply of cellulosic agricultural residues and industrial by-products that is produced each year is a prospective resource of biomass suitable for conversion to useful products such as feedstock for the chemicals industry and feedstuffs for the livestock industry. Conversions of such biomass is poor at present, and utilization is inefficient, because of physio-chemical barriers to biological degradation and (or) anti-quality components such as toxicants that restrict biological usages. Improvements in biodegradability of ligno-cellulosic materials have been accomplished by gamma-ray and electron-beam irradiation at intermediate dosage (˜ 50 Mrad; .5 MGy); but applications of the technology have been hampered by questionable interpretations of results. Recent research with organic wastes such as sewage sludge and straw suggests opportunity for important applications of irradiation technology in enhancement of biomass conversion. Data from experiments using irradiated straw as feed for ruminants are presented and discussed in relation to research on prospective usage of sewage products as feed for ruminants. Findings are discussed in regard to prospective applications in industrial fermentation processes. Possible usage of irradiation technology for destruction of toxicants in exotic plants is considered in regard to prospective new feedstuffs.

  8. Irradiance Variability of the Sun

    NASA Technical Reports Server (NTRS)

    Froehlich, Claus

    1990-01-01

    Direct measurements of the solar constant--the total irradiance at mean Sun-Earth distance--during the last ten years from satellites show variations over time scales from minutes to years and decades. At high frequencies the spectral power is determined by granulation, super- and mesogranulation. In the 5-minute range, moreover, it is dominated by power from the solar p-mode oscillations. Their power and frequencies change with time, yielding information about changes in the convection zone. During periods of several hours, the power is steadily increasing and may be partly due to solar gravity modes. The most important variance is in the range from days to several months and is related to the photospheric features of solar activity, decrease of the irradiance during the appearance of sunspots, and increasing by faculae and the magnetic network. Long-term modulation by the 11-year activity cycle are observed conclusively with the irradiance being higher during solar maximum. All these variations can be explained--at least qualitatively--by their manifestation on the photosphere. For the long-term changes, the simultaneous changes of the frequencies of solar p-mode oscillations suggest a more global origin of the variations. Indeed, it seems that the observed irradiance modulation is a true luminosity change with the magnetic cycle of the Sun.

  9. Centurion — a revolutionary irradiator

    NASA Astrophysics Data System (ADS)

    McKinney, Dan; Perrins, Robert

    2000-03-01

    The facility characteristics for irradiation of red meat and poultry differ significantly from those of medical disposables. This paper presents the results of the market requirement definition which resulted in an innovative conceptual design. The process and the "state of the art tools" used to bring this abstract idea into a proof of concept are presented.

  10. Food Irradiation Research and Technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food Irradiation is a safe and effective U.S. Food and Drug Administration (FDA) approved process that can be used to disinfest or delay the maturation of fruits and vegetables, improve the microbiological safety of shellfish, eggs, raw meat and poultry, spices, and seeds used for sprouting. FDA ap...

  11. Microstructural processes in irradiated materials

    NASA Astrophysics Data System (ADS)

    Byun, Thak Sang; Morgan, Dane; Jiao, Zhijie; Almer, Jonathan; Brown, Donald

    2016-04-01

    These proceedings contain the papers presented at two symposia, the Microstructural Processes in Irradiated Materials (MPIM) and Characterization of Nuclear Reactor Materials and Components with Neutron and Synchrotron Radiation, held in the TMS 2015, 144th Annual Meeting & Exhibition at Walt Disney World, Orlando, Florida, USA on March 15-19, 2015.

  12. Ultrasonic Transducer Irradiation Test Results

    SciTech Connect

    Daw, Joshua; Palmer, Joe; Ramuhalli, Pradeep; Keller, Paul; Montgomery, Robert; Chien, Hual-Te; Kohse, Gordon; Tittmann, Bernhard; Reinhardt, Brian; Rempe, Joy

    2015-02-01

    Ultrasonic technologies offer the potential for high-accuracy and -resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other ongoing efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of identified ultrasonic transducer materials capable of long term performance under irradiation test conditions. For this reason, the Pennsylvania State University (PSU) was awarded an ATR NSUF project to evaluate the performance of promising magnetostrictive and piezoelectric transducers in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2. The goal of this research is to characterize and demonstrate magnetostrictive and piezoelectric transducer operation during irradiation, enabling the development of novel radiation-tolerant ultrasonic sensors for use in Material Testing Reactors (MTRs). As such, this test is an instrumented lead test and real-time transducer performance data is collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers. To date, one piezoelectric

  13. Evaluation of irradiation hardening of proton irradiated stainless steels by nanoindentation

    NASA Astrophysics Data System (ADS)

    Yabuuchi, Kiyohiro; Kuribayashi, Yutaka; Nogami, Shuhei; Kasada, Ryuta; Hasegawa, Akira

    2014-03-01

    Ion irradiation experiments are useful for investigating irradiation damage. However, estimating the irradiation hardening of ion-irradiated materials is challenging because of the shallow damage induced region. Therefore, the purpose of this study is to prove usefulness of nanoindentation technique for estimation of irradiation hardening for ion-irradiated materials. SUS316L austenitic stainless steel was used and it was irradiated by 1 MeV H+ ions to a nominal displacement damage of 0.1, 0.3, 1, and 8 dpa at 573 K. The irradiation hardness of the irradiated specimens were measured and analyzed by Nix-Gao model. The indentation size effect was observed in both unirradiated and irradiated specimens. The hardness of the irradiated specimens changed significantly at certain indentation depths. The depth at which the hardness varied indicated that the region deformed by the indenter had reached the boundary between the irradiated and unirradiated regions. The hardness of the irradiated region was proportional to the inverse of the indentation depth in the Nix-Gao plot. The bulk hardness of the irradiated region, H0, estimated by the Nix-Gao plot and Vickers hardness were found to be related to each other, and the relationship could be described by the equation, HV = 0.76H0. Thus, the nanoindentation technique demonstrated in this study is valuable for measuring irradiation hardening in ion-irradiated materials.

  14. Irradiation hardening of reduced activation martensitic steels

    NASA Astrophysics Data System (ADS)

    Kimura, A.; Morimura, T.; Narui, M.; Matsui, H.

    1996-10-01

    Irradiation response on the tensile properties of 9Cr2W steels has been investigated following FFTF/MOTA irradiations at temperatures between 646 and 873 K up to doses between 10 and 59 dpa. The largest irradiation hardening accompanied by the largest decrease in the elongation is observed for the specimens irradiated at 646 K at doses between 10 and 15 dpa. The irradiation hardening appears to saturate at a dose of around 10 dpa at the irradiation temperature. No hardening but softening was observed in the specimens irradiated at above 703 K to doses of 40 and 59 dpa. Microstructural observation by transmission electron microscope (TEM) revealed that the dislocation loops with the a<100> type Burgers vector and small precipitates which were identified to be M 6C type carbides existed after the irradiation at below 703 K. As for the void formation, the average size of voids increased with increasing irradiation temperature from 646 to 703 K. No voids were observed above 703 K. Irradiation softening was attributed to the enhanced recovery of martensitic structure under the irradiation. Post-irradiation annealing resulted in hardening by the annealing at 673 K and softening by the annealing at 873 K.

  15. Biological effects of ultraviolet irradiation on bees

    SciTech Connect

    Es`kov, E.K.

    1995-09-01

    The influence of natural solar and artificial ultraviolet irradiation on developing bees was studied. Lethal exposures to irradiation at different stages of development were determined. The influence of irradiation on the variability of the morphometric features of bees was revealed. 5 refs., 1 fig.

  16. Food irradiation: research and technology, preface

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many interesting and exciting developments have occurred in the field of food irradiation since the publication of the first edition of Food Irradiation: Research and Technology in 2006. The 2nd edition of the book reviews our latest knowledge on food irradiation, highlights the current developments...

  17. Total Solar Irradiance Variability: A Review

    NASA Technical Reports Server (NTRS)

    Pap, Judit M.

    1996-01-01

    Observations of total solar irradiance from space within the last two decaades convinced the skeptics that total irradiance varies over a wide range of periodicities: from minutes to the 11-year solar activity cycle. Analyses based on these space-borne observations have demonstrated that the irradiance variations are directly related to changes at the photosphere and the solar interior.

  18. Schedule and status of irradiation experiments

    SciTech Connect

    Rowcliffe, A.F.; Grossbeck, M.L.

    1997-04-01

    To provide an updated summary of the status of irradiation experiments for the neutron-interactive materials program. The current status of reactor irradiation experiments is presented in tables summarizing the experimental objectives, conditions, and schedule. Currently, the program has two irradiation experiments in reactor; and 8 experiments in the planning or design stages. Postirradiation examination and testing is in progress on 18 experiments.

  19. Total Irradiance Monitor Observations of Total Solar Irradiance

    NASA Astrophysics Data System (ADS)

    Kopp, G.

    2007-12-01

    The Total Irradiance Monitor (TIM) is the most recent instrument launched to measure total solar irradiance (TSI) from space. This electrical substitution radiometer has on-orbit degradation tracking to provide very stable long- term measurements of the net solar radiation incident on the Earth, and the instrument continues the 29-year record of this natural driver of Earth climate. Currently flying on the SOlar Radiation and Climate Experiment (SORCE), the TIM has been providing stable, low-noise, and accurate measurements of TSI since early 2003. The TIM will next be flying on NASA's Glory climate mission and is one instrument of the Total Solar Irradiance Sensor (TSIS) selected to continue this important climate record well into the future. The SORCE/TIM has created renewed interest in the TSI absolute value and has acquired the first measurements of the total radiant energy released by large solar flares. Improvements in ground-based calibrations starting with the Glory/TIM will establish traceability linking current to upcoming measurements, solidifying the existing TSI climate data record in the undesirable event of a future data gap.

  20. Calculation of direct normal irradiation from global horizontal irradiation

    NASA Astrophysics Data System (ADS)

    Rodrigo, Pedro; Pérez-Higueras, Pedro J.; Almonacid, Florencia; Hontoria, Leocadio; Fernández, Eduardo F.; Rus, Catalina; Fernández, Juan I.; Gómez, Pedro; Almonacid, Gabino

    2012-10-01

    Concentrator Photovoltaic (CPV) systems only work with the Direct Normal Irradiance (DNI), so a knowledge of DNI data is required for the design and evaluation of these kinds of systems. DNI is not always measured at ground meteorological stations due to equipment costs. In recent years, several spatial databases that estimate DNI from satellite data have been developed. These databases are a very useful tool for CPV applications. However, the databases present uncertainty and provide different values of DNI. This lack of DNI data and the uncertainty of available data contrast with the availability of reliable global horizontal irradiation data, which is easy to find or measure. In this paper, a simple procedure for estimating DNI from global horizontal irradiation is presented. It does not try to improve the existing methods, but meets the basic requirements for the analysis of CPV systems. The method can be easily implemented in a spreadsheet or in computer programs in renewable energy and its accuracy is similar than that of the existing databases.

  1. Thematic Mapper bandpass solar exoatmospheric irradiances

    NASA Technical Reports Server (NTRS)

    Markham, B. L.; Barker, J. L.

    1987-01-01

    Based on solar irradiance data published by Neckel and Labs (1984) and Iqbal (1983), the solar exoatmospheric irradiances for Thematic Mapper (TM) bands 1, 2, 3, and 4 have been calculated. Results vary by up to 1 percent from previous published values, which were based on the earlier data of Neckel and Labs. For TM bands 5 and 7, integrated solar exoatmospheric irradiances have also been recalculated using solar irradiance data published by Labs and Neckel (1968), Arvesen et al. (1969), and Iqbal (1983). These irradiances vary by up to 6 percent from previously published results, which were based on data published by Thekaekara (1972).

  2. Design of YCF-1 mobile γ irradiator

    NASA Astrophysics Data System (ADS)

    Hehu, Zhang; Chuanzhen, Wang

    1993-07-01

    YCF-1 Mobile irradiator is designed by BINE of China. It has been put into running in YanJi city of Jilin province. It is able to be moved to border and distance places and area lumped and spreading out of agricultural products to service. It can play a important role in demonstration and extending irradiation technology in food irradiation, disinfestation, sterilization and quarantine, etc. This paper describes the features and design considerations of mobile irradiator. This irradiator adopted Cesium-137 source. The design capacity of loading source is 9.25PBq (250kCi), A half-time of Cs- 137 is 30.2 years long, exchanging source is not needed utilization rate of energy is higher, and the shielding is thinner, The Weight is lighter, The dose rate on the surface of it is 0.0025mSv/h in accordance with national standard. The internal size of irradiation room is 1800×1800×900mm (L×W×H), The sheilding of irradiation room is a steel shell filled with lead. The thickness of lead is 18cm. The irradiator is installed on a special flat truck. The size of the truck is 7000×3400×4200mm (L×W×H). The weight of irradiator is more than 80 150kw. The main components and parts of irradiator are: source, source racks and hoist, irradiation chamber, storage source chamber, the product's transport system, dose monitoring system, ventilation system and safety interlock system, etc.

  3. Future Satellite Observations of Solar Irradiance

    NASA Technical Reports Server (NTRS)

    Cahalan, R. F.; Rottman, G.; Woods, T.; Lawrence, G.; Harder, J.; McClintock, W.; Kopp, G.

    2003-01-01

    Required solar irradiance measurements for climate studies include those now being made by the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) onboard the SORCE satellite, part of the Earth Observing System fleet of NASA satellites. Equivalent or better measures of Total Solar Irradiance (TSI) and Spectral Solar Irradiance (SSI, 200 to 2000 nm) are planned for the post-2010 satellites of the National Polar-orbiting Operational Environmental Satellite System ("OESS). The design life of SORCE is 5 years, so a "Solar Irradiance Gap Filler" EOS mission is being planned for launch in the 2007 time frame, to include the same TSI and SSI measurements. Besides avoiding any gap, overlap of the data sources is also necessary for determination of possible multi-decadal trends in solar irradiance. We discuss these requirements and the impacts of data gaps, and data overlaps, that may occur in the monitoring of the critical solar radiative forcing.

  4. Comparison of Recent Total Irradiance Measurements

    NASA Astrophysics Data System (ADS)

    Helizon, R.; Pap, J.

    2002-12-01

    Total solar irradiance has been measured since 1978 from various satellites. Since the absolute accuracy of the current irradiance measurements is about 0.2%, one needs to compile composite irradiance time series to study long-term changes and to establish whether there are any secular variations over the last two and half decades. In this paper we compare the UARS/ACRIM II and SOHO/VIRGO total irradiance data as well as the SOHO/VIRGO and ACRIM III total irradiance. Our main goal is to validate the newly processed ACRIM II total irradiance. Comparison of the SOHO/VIRGO and ACRIM III data will also help to establish whether the high total irradiance values for the maximum of solar cycle 23 represent real solar, rather than, instrumental events.

  5. Irradiation effects on hydrases for biomedical applications

    NASA Astrophysics Data System (ADS)

    Furuta, Masakazu; Ohashi, Isao; Oka, Masahito; Hayashi, Toshio

    2000-03-01

    To apply an irradiation technique to sterilize "Hybrid" biomedical materials including enzymes, we selected papain, a well-characterized plant endopeptidase as a model to examine durability of enzyme activity under the practical irradiation condition in which limited data were available for irradiation inactivation of enzymes. Dry powder and frozen aqueous solution of papain showed significant durability against 60Co-gamma irradiation suggesting that, the commercial irradiation sterilizing method is applicable without modification. Although irradiation of unfrozen aqueous papain solution showed an unusual change of the enzymatic activity with the increasing doses, and was totally inactivated at 15 kGy, we managed to keep the residual activity more than 50% of initial activity after 30-kGy irradiation, taking such optimum conditions as increasing enzyme concentration from 10 to 100 mg/ml and purging with N 2 gas to suppress the formation of free radicals.

  6. Proton Irradiation Creep in Pyrocarbon

    SciTech Connect

    Was, Gary S.; Campbell, Anne

    2011-10-01

    This project aims to understand irradiation creep in pyrocarbon using proton irradiation under controlled stresses and temperatures. Experiments will be conducted over a range of temperatures and stresses per the proposal submitted. The work scope will include the preparation of samples, measurement of deposition thickness, thickness uniformity, and anisotropy. The samples produced will be made in strips, which will be used for the creep experiments. Materials used will include pyrolytic carbon (PyC), Highly Oriented Pyrolytic Graphite (HOPG), or graphite strip samples in that order depending upon success. Temperatures tested under will range from 800°C to 1200°C, and stresses from 6MPa to 20.7MPa. Optional testing may occur at 900°C and 1100°C and stresses from 6MPa to 20.7MPa if funding is available.

  7. Hydrazine degradation by ultrasonic irradiation.

    PubMed

    Nakui, Hiroyuki; Okitsu, Kenji; Maeda, Yasuaki; Nishimura, Rokurou

    2007-07-31

    The influence of pH on the degradation of hydrazine with a concentration of 0.1mmol/L was investigated under the stirring (300rpm) and ultrasonic irradiation conditions (200kHz, 200W) in the pH range of 1-9. It was found that the hydrazine degradation depended greatly upon pH under the ultrasonic irradiation condition, while it did not take place over the whole pH range under the stirring condition. Although it has been known that OH radicals and hydrogen peroxide are sonochemically formed from water, it was considered that the OH radicals played an important role of the hydrazine degradation, but not hydrogen peroxide. The pH dependence of the hydrazine degradation was discussed in terms of the relationship between the chemical structure and the basic dissociation constants of hydrazine. PMID:17513042

  8. GTL-1 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; G. S. Chang; N. E. Woolstenhulme; D. M. Wachs

    2012-01-01

    The primary objective of the Gas Test Loop (GTL-1) miniplate experiment is to confirm acceptable performance of high-density (i.e., 4.8 g-U/cm3) U3Si2/Al dispersion fuel plates clad in Al-6061 and irradiated under the relatively aggressive Booster Fast Flux Loop (BFFL) booster fuel conditions, namely a peak plate surface heat flux of 450 W/cm2. As secondary objectives, several design and fabrication variations were included in the test matrix that may have the potential to improve the high-heat flux, high-temperature performance of the base fuel plate design.1, 2 The following report summarizes the life of the GTL-1 experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.

  9. Food irradiation development in Pakistan

    NASA Astrophysics Data System (ADS)

    Khan, I.

    The large scale trials were held to extend the storage life of potatoes, onions and dry fruits by gamma radiation. It was concluded that radiation preservation of potatoes and onions was much cheaper as compared to conventional methods. A dose of 1 kGy can control the insects in dry fruits and nuts. The consumers' acceptability and market testing performed during the last four years are also conducive to the commercialization of the technology in this country. The Government of Pakistan has accorded clearance for the irradiation of some food items like potatoes, onions, garlic and spices for human consumption. The Pakistan Radiation Services (PARAS), the commercial irradiator (200 Kci) at Lahore, has already started functioning in April, 1987. It is planned to start large scale sterilization of spices by gamma radiation in PARAS shortly.

  10. Mobile gamma-irradiation robot

    NASA Astrophysics Data System (ADS)

    Teply, J.; Franek, C.; Vocilka, J.; Stetka, R.; Vins, J.; Krotil, J.; Garba, A.

    1993-07-01

    The source container with 98 TBq of 137Cs and shielding made from depleted uranium has the total weight of 264 kg, height of 0.370 and diameter 0.272 m. The container is joined to accessories allowing movment of the radiation beam. The dose rate at a distance of 0.4 m in the beam axis is 50 Gy/h. Various technical means are available for manipulation and transport. The irradiation process proceeds according to a precalculated program. The safety measures have been taken to secure the possible application in historical buildings and similar objects. The licence from health physics authorities has been obtained. The first irradiation process performed is described.

  11. RERTR-8 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-8, was designed to test monolithic mini-fuel plates fabricated via hot isostatic pressing (HIP), the effect of molybdenum (Mo) content on the monolithic fuel behavior, and the efficiency of ternary additions to dispersion fuel particles on the interaction layer behavior at higher burnup. The following report summarizes the life of the RERTR-8 experiment through end of irradiation, including as-run neutronic analysis, thermal analysis and hydraulic testing results.

  12. RERTR-13 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-13 was designed to assess performance of different types of neutron absorbers that can be potentially used as burnable poisons in the low enriched uranium-molybdenum based dispersion and monolithic fuels.1 The following report summarizes the life of the RERTR-13 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  13. Microstructure evolution in irradiated materials

    SciTech Connect

    Caturla, M

    1999-11-30

    Study the interaction of defects produced during irradiation or deformation of a metal with the microstructure of that particular material, such as dislocations and grain boundaries. In particular we will study the interaction of dislocation with interstitial loops and stacking fault tetrahedral, and the production of displacement cascades close to dislocations and grain boundaries. The data obtained from these simulations will be used as input to diffusion models and dislocation dynamics models.

  14. Two-Site Evaluation of the Repeatability and Precision of an Automated Dual-Column Hydrogen/Deuterium Exchange Mass Spectrometry Platform.

    PubMed

    Cummins, David J; Espada, Alfonso; Novick, Scott J; Molina-Martin, Manuel; Stites, Ryan E; Espinosa, Juan Felix; Broughton, Howard; Goswami, Devrishi; Pascal, Bruce D; Dodge, Jeffrey A; Chalmers, Michael J; Griffin, Patrick R

    2016-06-21

    Hydrogen/deuterium exchange coupled with mass spectrometry (HDX-MS) is an information-rich biophysical method for the characterization of protein dynamics. Successful applications of differential HDX-MS include the characterization of protein-ligand binding. A single differential HDX-MS data set (protein ± ligand) is often comprised of more than 40 individual HDX-MS experiments. To eliminate laborious manual processing of samples, and to minimize random and gross errors, automated systems for HDX-MS analysis have become routine in many laboratories. However, an automated system, while less prone to random errors introduced by human operators, may have systematic errors that go unnoticed without proper detection. Although the application of automated (and manual) HDX-MS has become common, there are only a handful of studies reporting the systematic evaluation of the performance of HDX-MS experiments, and no reports have been published describing a cross-site comparison of HDX-MS experiments. Here, we describe an automated HDX-MS platform that operates with a parallel, two-trap, two-column configuration that has been installed in two remote laboratories. To understand the performance of the system both within and between laboratories, we have designed and completed a test-retest repeatability study for differential HDX-MS experiments implemented at each of two laboratories, one in Florida and the other in Spain. This study provided sufficient data to do both within and between laboratory variability assessments. Initial results revealed a systematic run-order effect within one of the two systems. Therefore, the study was repeated, and this time the conclusion was that the experimental conditions were successfully replicated with minimal systematic error. PMID:27224086

  15. Radioluminescence Investigation Of Ion-irradiated Phosphors

    SciTech Connect

    Jacobsohn, Luiz; Muenchausen, Ross; Bennett, Bryan

    2008-01-01

    Phosphors are materials that emit light under the excitation of incoming radiation. This property is used, among other applications, in radiation detection. Efficient energy transfer from the ionization track to the luminescent centers must occur to yield significant light output. Besides, the investigation of the effects of ion irradiation on the luminescence of phosphors is comparatively unexplored. In this work, we review radioluminescence (RL) investigation of ion-irradiated oxides and oxide phosphors, and present preliminary data on the effects of ion irradiation on the luminescence of intrinsic phosphor Bi{sub 4}Ge{sub 3}0{sub 12} (BGO). Commercial crystals were irradiated, and the irradiation effects characterized by means of RL measurements as a function of temperature, from 10K to room temperature (RT), and optical absorption measurements. Overall, surface modification induced by ion irradiation leads to higher luminescence output.

  16. Irradiation preservation of seafood: Literature review

    SciTech Connect

    Molton, P.M.

    1987-10-01

    The application of gamma-irradiation for extending the shelf life of seafood has been of interest for many years. This report reviews a number of studies on seafood irradiation conducted over the past several years. Topics covered include seafood irradiation techniques and dosages, species applicability and differences, the effects of packaging on seafood preservation, and changes in organoleptic acceptability as a result of irradiation. Particular attention is given to radiation effects (likely and unlikely) of concern to the public. These include the potential for generation of toxic chemical products, botulinum toxin production, and other health concerns. No scientifically defensible evidence of any kind was found for any harmful effect of irradiation of seafoods at the doses being considered (less than 300 krad), and all indications are that irradiation is an acceptable and needed additional tool for seafood preservation. 49 refs., 14 figs., 14 tabs.

  17. Renal graft irradiation in acute rejection

    SciTech Connect

    Pilepich, M.V.; Sicard, G.A.; Breaux, S.R.; Etheredge, E.E.; Blum, J.; Anderson, C.B.

    1983-03-01

    To evaluate the effect of graft irradiation in the treatment of acute rejection of renal transplants, a randomized study was conducted from 1978 to 1981. Patients with acute rejection were given standard medical management in the form of intravenous methylprednisolone, and were chosen randomly to receive either graft irradiation (175 rads every other day, to a total of 525 rads) or simulated (sham) irradiation. Eighty-three rejections occurring in 64 grafts were randomized to the protocol. Rejection reversal was recorded in 84.5% of control grafts and 75% of the irradiated grafts. Recurrent rejections were more frequent and graft survival was significantly lower in the irradiated group (22%) than in the control group (54%). Graft irradiation does not appear to be beneficial in the treatment of acute rejection of renal transplants when used in conjunction with high-dose steroids.

  18. HRB-22 irradiation phase test data report

    SciTech Connect

    Montgomery, F.C.; Acharya, R.T.; Baldwin, C.A.; Rittenhouse, P.L.; Thoms, K.R.; Wallace, R.L.

    1995-03-01

    Irradiation capsule HRB-22 was a test capsule containing advanced Japanese fuel for the High Temperature Test Reactor (HTTR). Its function was to obtain fuel performance data at HTTR operating temperatures in an accelerated irradiation environment. The irradiation was performed in the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL). The capsule was irradiated for 88.8 effective full power days in position RB-3B of the removable beryllium (RB) facility. The maximum fuel compact temperature was maintained at or below the allowable limit of 1300{degrees}C for a majority of the irradiation. This report presents the data collected during the irradiation test. Included are test thermocouple and gas flow data, the calculated maximum and volume average temperatures based on the measured graphite temperatures, measured gaseous fission product activity in the purge gas, and associated release rate-to-birth rate (R/B) results. Also included are quality assurance data obtained during the test.

  19. Calibration of an automatic TLD irradiator

    SciTech Connect

    Jang, J.C.; Pasciak, W.J. )

    1987-07-01

    The Panasonic UD-801 TLDs used in the U.S. Nuclear Regulatory Commission's environmental monitoring program are calibrated using the Williston Elin Model 2001 Irradiator. This article describes the procedure used to calibrate this irradiator for the delivery of exposures in the range of 40 to 1200 mR. A select group of TLDs, another source, and an NBS-calibrated ion chamber were used to perform a secondary calibration of the WE-2001. Extraneous exposure contributions (background radiation from the irradiator's source and exposure occurring during TLD travel into and out of the irradiation chamber) were measured and evaluated. The WE-2001 TLD Irradiator was calibrated to a total uncertainty of {plus minus}3.2%; however, TLD travel time exposures were found to be quite significant for the short irradiation times typically used in environmental applications.

  20. EPR Investigation of Irradiated Curry Powder

    SciTech Connect

    Duliu, O. G.; Ali, S. I.; Georgescu, R.

    2007-04-23

    Gamma-ray irradiated curry powder, a well priced oriental spice was investigated in order to establish the ability of EPR to detect the presence and time stability of free irradiation free-radicals. Accordingly, curry powder aliquots were irradiated with gradually increasing absorbed doses up to 11.3 kGy. The EPR spectra of all irradiated samples show the presence of al last two different species of free radicals, whose concentration increased monotonously with the absorbed doses. A 100 deg. C isothermal annealing of irradiated samples has shown a differential reduction of amplitude of various components of the initial spectra, but even after 3.6 h of thermal treatment, the remaining amplitude represents no less then 30% of the initial ones. The same peculiarities have been noticed after more than one year storage at room temperature, all of them being very useful in establishing the existence of any previous irradiation treatment.

  1. Irradiation embrittlement of neutron-irradiated low activation ferritic steels

    NASA Astrophysics Data System (ADS)

    Kayano, H.; Kimura, A.; Narui, M.; Sasaki, Y.; Suzuki, Y.; Ohta, S.

    1988-07-01

    Effects of neutron irradiation and additions of small amounts of alloying elements on the ductile-brittle transition temperature (DBTT) of three different groups of ferritic steels were investigated by means of the Charpy impact test in order to gain an insight into the development of low-activation ferritic steels suitable for the nuclear fusion reactor. The groups of ferritic steels used in this study were (1) basic 0-5% Cr ferritic steels, (2) low-activation ferritic steels which are FeCrW steels with additions of small amounts of V, Mn, Ta, Ti, Zr, etc. and (3) FeCrMo, Nb or V ferritic steels for comparison. In Fe-0-15% Cr and FeCrMo steels, Fe-3-9% Cr steels showed minimum brittleness and provided good resistance against irradiation embrittlement. Investigations on the effects of additions of trace amounts of alloying elements on the fracture toughness of low-activation ferritic steels made clear the optimum amounts of each alloying element to obtain higher toughness and revealed that the 9Cr-2W-Ta-Ti-B ferritic steel showed the highest toughness. This may result from the refinement of crystal grains and improvement of quenching characteristics caused by the complex effect of Ti and B.

  2. Irradiation Testing of Ultrasonic Transducers

    SciTech Connect

    Daw, Joshua; Tittmann, Bernhard; Reinhardt, Brian; Kohse, Gordon E.; Ramuhalli, Pradeep; Montgomery, Robert O.; Chien, Hual-Te; Villard, Jean-Francois; Palmer, Joe; Rempe, Joy

    2014-07-30

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. For this reason, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). The goal of this research is to characterize magnetostrictive and piezoelectric transducer survivability during irradiation, enabling the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). As such, this test will be an instrumented lead test and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers.

  3. Irradiation Testing of Ultrasonic Transducers

    SciTech Connect

    Daw, Joshua; Tittmann, Bernhard; Reinhardt, Brian; Kohse, Gordon E.; Ramuhalli, Pradeep; Montgomery, Robert O.; Chien, Hual-Te; Villard, Jean-Francois; Palmer, Joe; Rempe, Joy

    2013-12-01

    Ultrasonic technologies offer the potential for high accuracy and resolution in-pile measurement of a range of parameters, including geometry changes, temperature, crack initiation and growth, gas pressure and composition, and microstructural changes. Many Department of Energy-Office of Nuclear Energy (DOE-NE) programs are exploring the use of ultrasonic technologies to provide enhanced sensors for in-pile instrumentation during irradiation testing. For example, the ability of single, small diameter ultrasonic thermometers (UTs) to provide a temperature profile in candidate metallic and oxide fuel would provide much needed data for validating new fuel performance models. Other efforts include an ultrasonic technique to detect morphology changes (such as crack initiation and growth) and acoustic techniques to evaluate fission gas composition and pressure. These efforts are limited by the lack of existing knowledge of ultrasonic transducer material survivability under irradiation conditions. For this reason, the Pennsylvania State University (PSU) was awarded an Advanced Test Reactor National Scientific User Facility (ATR NSUF) project to evaluate promising magnetostrictive and piezoelectric transducer performance in the Massachusetts Institute of Technology Research Reactor (MITR) up to a fast fluence of at least 1021 n/cm2 (E> 0.1 MeV). The goal of this research is to characterize magnetostrictive and piezoelectric transducer survivability during irradiation, enabling the development of novel radiation tolerant ultrasonic sensors for use in Material and Test Reactors (MTRs). As such, this test will be an instrumented lead test and real-time transducer performance data will be collected along with temperature and neutron and gamma flux data. The current work bridges the gap between proven out-of-pile ultrasonic techniques and in-pile deployment of ultrasonic sensors by acquiring the data necessary to demonstrate the performance of ultrasonic transducers.

  4. Irradiation effects in ferritic steels

    NASA Astrophysics Data System (ADS)

    Lechtenberg, Thomas

    1985-08-01

    Since 1979 the Alloy Development for Irradiation Performance (ADIP) task funded by the US Department of Energy has been studying the 2-12Cr class of ferritic steels to establish the feasibility of using them in fusion reactor first wall/breeding blanket (FW/B) applications. The advantages of ferritic steels include superior swelling resistance, low thermal stresses compared to austenitic stainless steels, attractive mechanical properties up to 600°C. and service histories exceeding 100 000 h. These steels are commonly used in a range of microstructural conditions which include ferritic, martensitic. tempered martensitic, bainitic etc. Throughout this paper where the term "ferritic" is used it should be taken to mean any of these microstructures. The ADIP task is studying several candidate alloy systems including 12Cr-1MoWV (HT-9), modified 9Cr-1MoVNb, and dual-phased steels such as EM-12 and 2 {1}/{4}Cr-Mo. These materials are ferromagnetic (FM), body centered cubic (bcc), and contain chromium additions between 2 and 12 wt% and molybdenum additions usually below 2%. The perceived issues associated with the application of this class of steel to fusion reactors are the increase in the ductile-brittle transition temperature (DBTT) with neutron damage, the compatibility of these steels with liquid metals and solid breeding materials, and their weldability. The ferromagnetic character of these steels can also be important in reactor design. It is the purpose of this paper to review the current understanding of these bcc steels and the effects of irradiation. The major points of discussion will be irradiation-induced or -enhanced dimensional changes such as swelling and creep, mechanical properties such as tensile strength and various measurements of toughness, and activation by neutron interactions with structural materials.

  5. Safety Assurance for ATR Irradiations

    SciTech Connect

    S. Blaine Grover

    2006-10-01

    The Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL) is the world’s premiere test reactor for performing high fluence, large volume, irradiation test programs. The ATR has many capabilities and a wide variety of tests are performed in this truly one of a kind reactor, including isotope production, simple self-contained static capsule experiments, instrumented/controlled experiments, and loop testing under pressurized water conditions. Along with the five pressurized water loops, ATR may also have gas (temperature controlled) lead experiments, fuel boosted fast flux experiments, and static sealed capsules all in the core at the same time. In addition, any or all of these tests may contain fuel or moderating materials that can affect reactivity levels in the ATR core. Therefore the safety analyses required to ensure safe operation of each experiment as well as the reactor itself are complex. Each test has to be evaluated against stringent reactor control safety criteria, as well as the effects it could have on adjacent tests and the reactor as well as the consequences of those effects. The safety analyses of each experiment are summarized in a document entitled the Experiment Safety Assurance Package (ESAP). The ESAP references and employs the results of the reactor physics, thermal, hydraulic, stress, seismic, vibration, and all other analyses necessary to ensure the experiment can be irradiated safely in the ATR. The requirements for reactivity worth, chemistry compatibilities, pressure limitations, material issues, etc. are all specified in the Technical Safety Requirements and the Upgraded Final Safety Analysis Report (UFSAR) for the ATR. This paper discusses the ESAP process, types of analyses, types of safety requirements and the approvals necessary to ensure an experiment can be safely irradiated in the ATR.

  6. Food irradiation and airline catering.

    PubMed

    Preston, F S

    1988-04-01

    Food poisoning from contaminated airline food can produce serious consequences for airline crew and passengers and can hazard flight. While irradiation of certain foodstuffs has been practised in a number of countries for some years, application of the process has not been made to complete meals. This paper considers the advantages, technical considerations, costs and possible application to airline meals. In addition, the need to educate the public in the advantages of the process in the wake of incidents such as Chernobyl is discussed. PMID:3370047

  7. AFIP-6 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-09-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-6 was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a length prototypic to that of the ATR fuel plates (45 inches in length). The AFIP-6 test was the first test with plates in a swaged condition with longer fuel zones of approximately 22.5 inches in length1,2. The following report summarizes the life of the AFIP-6 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  8. Thymus irradiation for myasthenia gravis

    SciTech Connect

    Currier, R.D.; Routh, A.; Hickman, B.T.; Douglas, M.A.

    1983-01-01

    Twenty-eight patients with progressive myasthenia gravis without thymoma received treatment of 3000 rads (30 Gy) to the anterior mediastinum, and a followup was conducted for five to 18 years. Twenty-four patients had generalized myasthenia, and four had ocular myasthenia gravis. Twenty patients with generalized myasthenia survived the several month post-treatment period and improved, but four died during that period. The improvement lasted a median of 1.5 years, and older patients had longer remissions than younger patients. The four patients who had ocular myasthenia did not change after treatment. Mediastinal irradiation produces a temporary remission in generalized myasthenia.

  9. Raman Spectroscopy of Irradiated Tissue Samples

    NASA Astrophysics Data System (ADS)

    Alexa, P.; Synytsya, A.; Volka, K.; de Boer, J.; Besserer, J.; Froschauer, S.; Loewe, M.; Moosburger, M.; Würkner, M.

    2003-06-01

    Tissue samples (skin of mice, normal and tumor, skin of a woman, normal and tumor) were irradiated by protons from the Munich tandem accelerator. The samples were analysed using Raman spectroscopy at the Institute of Chemical Technology in Prague by measuring the intensity of signals sensitive to radiation damage. Effects depending on the delivered dose were found. Proton-irradiation effects are then compared to those of gamma-irradiation.

  10. Development of an 241Am applicator for intracavitary irradiation of gynecologic cancers.

    PubMed

    Nath, R; Peschel, R E; Park, C H; Fischer, J J

    1988-05-01

    Sealed sources of 241Am that emit primarily 60 keV photons produce relative dose distributions in water comparable to those from 137Cs or 226Ra sources and can produce dose rates of up to 100 cGy/hr at 1 cm in water. Also, 241Am gamma rays can be effectively shielded by thin layers of high atomic number materials (HVL is 1/8th mm of lead) placed on the applicator or inside some body cavities (for example, hypaque in bladder, barium sulphate in rectum). These properties of 241Am sources open a new approach to optimizing intracavitary irradiation of various cancers by allowing a reduction in dose and volume of irradiated critical organs or by increasing tumor doses. The relative ease with which highly effective shielding is achievable with 241Am sources would allow the design and fabrication of partially shielded applicators which can produce asymmetric dose distributions to allow unidirectional irradiation of localized lesions. Design and dosimetry characteristics of a gynecological applicator containing 241Am sources are presented. The applicator consists of a 2, 3, or 4 segment vaginal plaque (loaded with 2 and 5 Ci 241Am sources) and a tandem made up of a single 8 Ci 241Am source. Dose rates at 2 cm from the plaques are 42.0, 47.4, 58.3 and 56.7 cGy/hr for 5-5, 5-4-5, 5-5-5, and 5-4-4-5 Ci plaques, respectively. The 5-4-5 Ci plaque in combination with the 8 Ci tandem produces dose rates of 60.0 and 22.8 cGy/hr to points A and B, respectively. Surface dose rates on the plaque applicators are 143, 124, 142 and 132 cGy/hr for 5-5, 5-4-5, 5-5-5 and 5-4-4-5 Ci applicators, respectively. The shielding effect of a 0.5 mm thick lead foil on one side of the 5-4-5 Ci applicator is found to be a factor of 16.8; for example, the dose rate at 2 cm from the unshielded side is 42.0 cGy/hr compared to a dose rate of 2.5 cGy/hr at 2 cm from the shielded side. Initial clinical experience with this applicator in the treatment of recurrent gynecological lesions is also presented

  11. Grafting of styrene into pre-irradiated fluoropolymer films: Influence of base material and irradiation temperature

    NASA Astrophysics Data System (ADS)

    Lappan, Uwe; Geißler, Uwe; Gohs, Uwe; Uhlmann, Steffi

    2010-10-01

    In this study, the influence of irradiation temperature on mechanical properties of three fluoropolymers and on grafting of styrene into the polymers by the pre-irradiation method was investigated. Electron paramagnetic resonance spectroscopy and infrared spectroscopy were used to characterize the irradiated polymers regarding trapped radical species and changes in the chemical structure, respectively. For poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) the irradiation temperature was found to be an important factor for tensile strength and elongation at break of the pre-irradiated film. No strong effect of irradiation temperature on the mechanical properties was noticed for poly(tetrafluoroethylene-co-ethylene) (ETFE); however the yield of grafting drops at high irradiation temperatures. Finally, mechanical properties of poly(tetrafluoroethylene) (PTFE) were found to be dramatically altered, even if the film was irradiated at elevated temperature.

  12. Solar irradiance short wave radiation users guide

    NASA Astrophysics Data System (ADS)

    Martinolich, Paul; Arnone, Robert A.

    1995-05-01

    Solar irradiance for short wave radiation (400-700 nm) at the sea surface can be calculated using inputs obtained from satellite systems and model estimates. The short wave solar irradiance is important for estimating the surface heating that occurs in the near surface and estimating the available irradiance for biological growth in the upper ocean. The variability of the solar irradiance is believed to have significant influence on the global carbon cycle. This users guide provides an understanding of the models and operational procedures for using the software and understanding the results.

  13. Thermoluminescence analysis of irradiated oyster shells.

    PubMed

    Cruz-Zaragoza, E; Marcazzó, J; Della Monaca, S; Boniglia, C; Gargiulo, R; Bortolin, E

    2012-12-01

    This paper reports the thermoluminescence (TL) analysis performed on the oyster shells powder. TL response of (60)Co gamma-rays irradiated samples were studied in the range from 80 Gy to 8 kGy doses. TL signal of irradiated shell powder was higher as compared to the unirradiated control samples, which allowed to identify the irradiated oysters. Results show that the oyster shells have good TL properties and can be useful for the identification of irradiated seafood as well as for the evaluation of the treatment dose. PMID:22341648

  14. Study of irradiation creep of vanadium alloys

    SciTech Connect

    Tsai, H.; Strain, R.V.; Smith, D.L.

    1997-08-01

    Thin-wall tubing was produced from the 832665 (500 kg) heat of V-4 wt.% Cr-4 wt.% Ti to study its irradiation creep behavior. The specimens, in the form of pressurized capsules, were irradiated in Advanced Test Reactor and High Flux Isotope Reactor experiments (ATR-A1 and HFIR RB-12J, respectively). The ATR-A1 irradiation has been completed and specimens from it will soon be available for postirradiation examination. The RB-12J irradiation is not yet complete.

  15. Free radical kinetics on irradiated fennel

    NASA Astrophysics Data System (ADS)

    Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

    2008-09-01

    Herein, an electron spin resonance study on the behavior of organic radicals in fennel before and after irradiation is reported. The spectrum of irradiated fennel composed of the spectrum component derived from the un-irradiated sample (near g=2.005) and the spectra components derived from carbohydrates. The time decay of intensity spectral components was well explained by first-order kinetics with a variety of rate constants. Especially, the signal at near g=2.02 ascribed to stable cellulose-derivative components is expected to be a good indicator in the identification of irradiated plant samples.

  16. Comparison of irradiation creep and swelling of an austenitic alloy irradiated in FFTF and PFR

    SciTech Connect

    Garner, F.A.; Toloczko, M.B.; Munro, B.; Adaway, S.; Standring, J.

    1999-10-01

    comparative irradiation of identically constructed creep tubes in the Fast Flux Test Facility (FFTF) and the Prototypic Fast Reactor (PFR) shows that differences in irradiation conditions arising from both reactor operation and the design of the irradiation vehicle can have a significant impact on the void swelling and irradiation creep of austenitic stainless steels. In spite of these differences, the derived creep coefficients fall within the range of previously observed values for 316 SS.

  17. Food irradiation: Key research needs

    SciTech Connect

    Morehouse, K.M. )

    1993-01-01

    Treatment of foods with ionizing radiation reduces microbial infection and insect infestations, inhibits sprouting, and delays maturation, thereby extending the shelf life of foods. The treatment of different types of foods with ionizing radiation for specific purposes is accepted in several countries, although it is prohibited in others. The US Food and Drug Administration has established regulations to allow the treatment of several different foods with ionizing radiation and has received petitions for the approval of radiation treatment of additional foods. When carried out according to established good manufacturing practices, food irradiation yields safe, wholesome foods. The irradiated product may be often chemically or microbiologically [open quotes]safer[close quotes] than the nonirradiated product. This paper presents several areas of scientific research in which more information would facilitate the expansion of this technology and points out major areas of concern. The question of the public acceptance of foods that have been treated with ionizing radiation is discussed only briefly in order to make the presentation complete.

  18. Spectroscopic analysis of irradiated erythrocytes

    NASA Astrophysics Data System (ADS)

    Selim, Nabila S.; Desouky, Omar S.; Ismail, Nagla M.; Dakrory, Amira Z.

    2011-12-01

    The aim of the present work is to study the effect of gamma radiation on the lipid part of the erythrocyte membrane, and to test the efficiency of lipoic acid as a radioprotector. This effect was evaluated using electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) spectroscopy. The results showed an increase in the number of spin density by 14%, 22% and 65% after exposure to 25, 50 and 100 Gy respectively; whereas there was a decline in the obtained density after incubation with lipoic acid by a factor of approximately 32%. The FT-IR spectra of the irradiated erythrocytes samples showed a marked decrease in the intensity of all characteristic peaks, which increased as the irradiation dose increased. The second-derivative of these spectra, allow the conformationally sensitive membrane acyl chain methylene stretching modes to be separated from the protein (mostly hemoglobin) vibrations that dominate the spectra of intact cells. The 2850 cm -1 band showed changes in the band shape and position after exposure to 50 and 100 Gy. Therefore it can be concluded that the band at 2850 cm -1 only is useful in monitoring the radiation effect of the lipids cell membrane intact cells.

  19. Updates to ISO 21348 (determining solar irradiances)

    NASA Astrophysics Data System (ADS)

    Tobiska, W. Kent

    2012-07-01

    The ISO 21348 (Determining Solar Irradiances) International Standard is going through a document update. A consensus solar spectrum, solar indices/proxies descriptions, solar model descriptions, and solar measurement descriptions are among the Annexes that are proposed to the standard. These topics will be reviewed and described. The International Standards Organization (ISO) published IS 21348 in 2007 after 7 years of development by the international scientific community. In ISO, documents are reviewed on a regular basis and reaffirmed, updated, or deleted according to the votes of national delegations represented in ISO. IS 21348 provides guidelines for specifying the process of determining solar irradiances. Solar irradiances are reported through products such as measurement sets, reference spectra, empirical models, theoretical models and solar irradiance proxies or indices. These products are used in scientific and engineering applications to characterize within the natural space environment solar irradiances that are relevant to space systems and materials. Examples of applications using input solar irradiance energy include the determination of atmospheric densities for spacecraft orbit determination, attitude control and re-entry calculations, as well as for debris mitigation and collision avoidance activity. Direct and indirect pressure from solar irradiance upon spacecraft surfaces also affects attitude control separately from atmospheric density effects. Solar irradiances are used to provide inputs for a) calculations of ionospheric parameters, b) photon-induced radiation effects, and c) radiative transfer modeling of planetary atmospheres. Input solar irradiance energy is used to characterize material properties related to spacecraft thermal control, including surface temperatures, reflectivity, absorption and degradation. Solar energy applications requiring a standard process for determining solar irradiance energy include i) solar cell power

  20. Mechanical response of proton beam irradiated nitinol

    NASA Astrophysics Data System (ADS)

    Afzal, Naveed; Ghauri, I. M.; Mubarik, F. E.; Amin, F.

    2011-01-01

    The present investigation deals with the study of mechanical behavior of proton beam irradiated nitinol at room temperature. The specimens in austenitic phase were irradiated over periods of 15, 30, 45 and 60 min at room temperature using 2 MeV proton beam obtained from Pelletron accelerator. The stress-strain curves of both unirradiated and irradiated specimens were obtained using a universal testing machine at room temperature. The results of the experiment show that an intermediate rhombohedral (R) phase has been introduced between austenite and martensite phase, which resulted in the suppression of direct transformation from austenite to martensite (A-M). Stresses required to start R-phase ( σRS) and martensitic phase ( σMS) were observed to decrease with increase in exposure time. The hardness tests of samples before and after irradiation were also carried out using Vickers hardness tester. The comparison reveals that the hardness is higher in irradiated specimens than that of the unirradiated one. The increase in hardness is quite sharp in specimens irradiated for 15 min, which then increases linearly as the exposure time is increased up to 60 min. The generation of R-phase, variations in the transformation stresses σRS and σMS and increase in hardness of irradiated nitinol may be attributed to lattice disorder and associated changes in crystal structure induced by proton beam irradiation.

  1. TSIS: The Total Solar Irradiance Sensor

    NASA Astrophysics Data System (ADS)

    Sparn, T.; Pilewskie, P.; Harder, J.; Kopp, G.; Richard, E.; Fontenla, J.; Woods, T.

    2008-12-01

    The Total Solar Irradiance Sensor (TSIS) is a dual-instrument package that will acquire solar irradiance in the next decade on the National Polar-orbiting Operational Environmental Satellite System (NPOESS). Originally de-manifested during the 2006 NPOESS restructuring, TSIS was restored following a decision by the NPOESS Executive Committee earlier this year because of its critical role in determining the natural forcings of the climate system and the high priority given it by the 2007 Earth Science Decadal Survey. TSIS is comprised of the Total Irradiance Monitor, or TIM, which measures the total solar irradiance (TSI) that is incident at the boundaries of the atmosphere; and the Spectral Irradiance Monitor, or SIM, which measures solar spectral irradiance (SSI) from 200 nm to 2400 nm (96 percent of the TSI). The TSIS TIM and SIM are heritage instruments to those currently flying on the NASA Solar Irradiance and Climate Experiment (SORCE). Both were selected as part of the TSIS because of their unprecedented measurement accuracy and stability, and because both measurements are essential to constraining the energy input to the climate system and interpreting the response of climate to external forcing. This paper will describe those attributes of TSIS which uniquely define its capability to continue the 30-year record of TSI and to extend the new 5-year record of SSI. The role of the solar irradiance data record in the present climate state, as well as in past and future climate change, will also be presented.

  2. Schedule and status of irradiation experiments

    SciTech Connect

    Rowcliffe, A.F.; Grossbeck, M.L.; Robertson, J.P.

    1998-03-01

    The current status of reactor irradiation experiments is presented in tables summarizing the experimental objectives, conditions, and schedule. Currently, the program has four irradiation experiments in reactor, and five experiments in the design or construction stages. Postirradiation examination and testing is in progress on ten experiments.

  3. A Retailer's Experience with Irradiated Foods

    SciTech Connect

    James P. Corrigan

    2000-11-12

    A food irradiation success story comes from Northbrook, Illinois, where Carrot Top, Inc., has been routinely carrying irradiated food for more than 7 yr. This paper presents the experiences of Carrot Top during those years, details the marketing approaches used, and summarizes the resulting sales figures.

  4. Identification of irradiated apples for phytosanitary purposes

    NASA Astrophysics Data System (ADS)

    Horak, Celina I.; Di Giorgio, Marina; Kairiyama, Eulogia

    2009-07-01

    The irradiation treatment of fresh fruits and vegetables for phytosanitary purposes is a satisfactory alternative method to others like fumigation and cold and hot treatments. Its use is increasing in several countries, and at present its approval is under revision by the National Regulatory Authorities. To verify the control process, apart from irradiation and dosimetry certificates, National Authorities require complementary evidence to show the efficacy of this treatment, especially when the documentation is not clear. The irradiation of fresh fruits produces single and double fragmentation in the DNA molecule, which can be measured using the microgel electrophoresis of individual cell (comet assay). The purpose of this work was to evaluate if it is possible to identify the irradiated apples for phytosanitary purposes from the others that were not treated. The possibility to estimate the absorbed dose was also evaluated. The methodology was carried out on the cell suspension obtained from irradiated seed cells with incremental doses (100, 200 and 300 Gy). The irradiation treatment for phytosanitary purposes to avoid emergency of codling moth ( Cydia pomonella) is 200 Gy. The fragmentation produced in the irradiated samples was proportional with the incremental doses applied. These results show that with this methodology it can be determined if the apple was irradiated or not. This comet assay is a simple, economical and interesting method that can be used, in case of necessity, by the National Authorities.

  5. Generic Irradiation Quarantine Treatments: The Next Steps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2006, USDA-APHIS published a landmark rule providing generic irradiation quarantine treatments. The rule approved irradiation doses of 150 Gy for any tephritid fruit fly and 400 Gy for all other insects except the pupa and adult stages of Lepidoptera. Therefore, if a pest risk assessment demonstr...

  6. Schedule and status of irradiation experiments

    SciTech Connect

    Rowcliffe, A.F.; Grossbeck, M.L.; Robertson, J.P.

    1998-09-01

    The current status of reactor irradiation experiments is presented in tables summarizing the experimental objectives, conditions, and schedule. Currently, the program has one irradiation experiment in reactor and five experiments in the design or construction stages. Postirradiation examination and testing is in progress on ten experiments.

  7. Passive SiC irradiation temperature monitor

    SciTech Connect

    Youngblood, G.E.

    1996-04-01

    A new, improved passive irradiation temperature monitoring method was examined after an irradiation test at 627{degrees}C. The method is based on the analysis of thermal diffusivity changes during postirradiation annealing of polycrystalline SiC. Based on results from this test, several advantages for using this new method rather than a method based on length or lattice parameter changes are given.

  8. Extracorporeal Irradiation in Malignant Bone Tumors.

    PubMed

    Bhandari, R B; Jha, A K; Neupane, P; Chaurasia, P P; Sigdel, A

    2015-01-01

    Extracorporeal irradiation (ECI) is relatively a rare method used in the management of malignant bone tumors (MBT). It consists of en block removal of the tumor bearing bone segment, removal of the tumor from the bone, irradiation and re implantation back in the body. PMID:27549504

  9. IRRADIATION FOR POSTHARVEST CONTROL OF QUARANTINE INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in the use of irradiation as a phytosanitary treatment for agricultural commodities is growing worldwide, particularly since international IPPC and CODEX standards now endorse and facilitate trade based on this disinfestation method. Irradiation is broadly effective against insects and mite...

  10. Reprocessing technology development for irradiated beryllium

    SciTech Connect

    Kawamura, H.; Sakamoto, N.; Tatenuma, K.

    1995-09-01

    At present, beryllium is under consideration as a main candidate material for neutron multiplier and plasma facing material in a fusion reactor. Therefore, it is necessary to develop the beryllium reprocessing technology for effective resource use. And, we have proposed reprocessing technology development on irradiated beryllium used in a fusion reactor. The preliminary reprocessing tests were performed using un-irradiated and irradiated beryllium. At first, we performed beryllium separation tests using un-irradiated beryllium specimens. Un-irradiated beryllium with beryllium oxide which is a main impurity and some other impurities were heat-treated under chlorine gas flow diluted with Ar gas. As the results high purity beryllium chloride was obtained in high yield. And it appeared that beryllium oxide and some other impurities were removed as the unreactive matter, and the other chloride impurities were separated by the difference of sublimation temperature on beryllium chloride. Next, we performed some kinds of beryllium purification tests from beryllium chloride. And, metallic beryllium could be recovered from beryllium chloride by the reduction with dry process. In addition, as the results of separation and purification tests using irradiated beryllium specimens, it appeared that separation efficiency of Co-60 from beryllium was above 96%. It is considered that about 4% Co-60 was carried from irradiated beryllium specimen in the form of cobalt chloride. And removal efficiency of tritium from irradiated beryllium was above 95%.

  11. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Irradiator pools. 36.33 Section 36.33 Energy NUCLEAR....02 millisievert (2 millirems) per hour. ... issued after July 1, 1993, irradiator pools must have no outlets more than 0.5 meter below the normal...

  12. In situ ion irradiation of zirconium carbide

    NASA Astrophysics Data System (ADS)

    Ulmer, Christopher J.; Motta, Arthur T.; Kirk, Mark A.

    2015-11-01

    Zirconium carbide (ZrC) is a candidate material for use in one of the layers of TRISO coated fuel particles to be used in the Generation IV high-temperature, gas-cooled reactor, and thus it is necessary to study the effects of radiation damage on its structure. The microstructural evolution of ZrCx under irradiation was studied in situ using the Intermediate Voltage Electron Microscope (IVEM) at Argonne National Laboratory. Samples of nominal stoichiometries ZrC0.8 and ZrC0.9 were irradiated in situ using 1 MeV Kr2+ ions at various irradiation temperatures (T = 20 K-1073 K). In situ experiments made it possible to continuously follow the evolution of the microstructure during irradiation using diffraction contrast imaging. Images and diffraction patterns were systematically recorded at selected dose points. After a threshold dose during irradiations conducted at room temperature and below, black-dot defects were observed which accumulated until saturation. Once created, the defect clusters did not move or get destroyed during irradiation so that at the final dose the low temperature microstructure consisted only of a saturation density of small defect clusters. No long-range migration of the visible defects or dynamic defect creation and elimination were observed during irradiation, but some coarsening of the microstructure with the formation of dislocation loops was observed at higher temperatures. The irradiated microstructure was found to be only weakly dependent on the stoichiometry.

  13. Cherry Irradiation Studies. 1984 annual report

    SciTech Connect

    Eakin, D.E.; Hungate, F.P.; Tingey, G.L.; Olsen, K.L.; Fountain, J.B.; Burditt, A.K. Jr.; Moffit, H.R.; Johnson, D.A.; Lunden, J.D.

    1985-04-01

    Fresh cherries, cherry fruit fly larvae, and codling moth larvae were irradiated using the PNL cobalt-60 facility to determine the efficacy of irradiation treatment for insect disinfestation and potential shelf life extension. Irradiation is an effective disinfestation treatment with no significant degradation of fruit at doses well above those required for quarantine treatment. Sufficient codling moth control was achieved at projected doses of less than 25 krad; cherry fruit fly control, at projected doses of less than 15 krad. Dose levels up to 60 krad did not adversely affect cherry quality factors tested. Irradiation above 60 krad reduced the firmness of cherries but had no significant impact on other quality factors tested. Irradiation of cherries below 80 krad did not result in any significant differences in sensory evaluations (appearance, flavor, and firmness) in tests conducted at OSU. Irradiation up to 200 krad at a temperature of about 25/sup 0/C (77/sup 0/F) did not measurably extend shelf life. Irradiation at 500 krad at 25/sup 0/C (77/sup 0/F) increased mold and rotting of cherries tested. There is no apparent advantage of irradiation over low-temperature fumigation.

  14. Preparation and characterization of mono-sheet bipolar membranes by pre-irradiation grafting method for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Guan, Yingjie; Fang, Jun; Fu, Tao; Zhou, Huili; Wang, Xin; Deng, Zixiang; Zhao, Jinbao

    2016-09-01

    A new method for the preparation of the mono-sheet bipolar membrane applied to fuel cells was developed based on the pre-irradiation grafting technology. A series of bipolar membranes were successfully prepared by simultaneously grafting of styrene onto one side of the poly(ethylene-co-tetrafluoroethylene) base film and 1-vinylimidazole onto the opposite side, followed by the sulfonation and alkylation, respectively. The chemical structures and microstructures of the prepared membranes were investigated by ATR-FTIR and SEM-EDS. The TGA measurements demonstrated the prepared bipolar membranes have reasonable thermal stability. The ion exchange capacity, water uptake and ionic conductivity of the membranes were also characterized. The H2/O2 single fuel cells using these membranes were evaluated and revealed a maximum power density of 107 mW cm-2 at 35 °C with unhumidified hydrogen and oxygen. The preliminary performances suggested the great prospect of these membranes in application of bipolar membrane fuel cells.

  15. AGR-1 Post Irradiation Examination Final Report

    SciTech Connect

    Demkowicz, Paul Andrew

    2015-08-01

    The post-irradiation examination (PIE) of the Advanced Gas Reactor (AGR)-1 experiment was a multi-year, collaborative effort between Idaho National Laboratory (INL) and Oak Ridge National Laboratory (ORNL) to study the performance of UCO (uranium carbide, uranium oxide) tristructural isotropic (TRISO) coated particle fuel fabricated in the U.S. and irradiated at the Advanced Test Reactor at INL to a peak burnup of 19.6% fissions per initial metal atom. This work involved a broad array of experiments and analyses to evaluate the level of fission product retention by the fuel particles and compacts (both during irradiation and during post-irradiation heating tests to simulate reactor accident conditions), investigate the kernel and coating layer morphology evolution and the causes of coating failure, and explore the migration of fission products through the coating layers. The results have generally confirmed the excellent performance of the AGR-1 fuel, first indicated during the irradiation by the observation of zero TRISO coated particle failures out of 298,000 particles in the experiment. Overall release of fission products was determined by PIE to have been relatively low during the irradiation. A significant finding was the extremely low levels of cesium released through intact coatings. This was true both during the irradiation and during post-irradiation heating tests to temperatures as high as 1800°C. Post-irradiation safety test fuel performance was generally excellent. Silver release from the particles and compacts during irradiation was often very high. Extensive microanalysis of fuel particles was performed after irradiation and after high-temperature safety testing. The results of particle microanalysis indicate that the UCO fuel is effective at controlling the oxygen partial pressure within the particle and limiting kernel migration. Post-irradiation examination has provided the final body of data that speaks to the quality of the AGR-1 fuel, building

  16. AGC-1 Irradiation Experiment Test Plan

    SciTech Connect

    R. L. Bratton

    2006-05-01

    The Advanced Graphite Capsule (AGC) irradiation test program supports the acquisition of irradiated graphite performance data to assist in the selection of the technology to be used for the VHTR. Six irradiations are planned to investigate compressive creep in graphite subjected to a neutron field and obtain irradiated mechanical properties of vibrationally molded, extruded, and iso-molded graphites for comparison. The experiments will be conducted at three temperatures: 600, 900, and 1200°C. At each temperature, two different capsules will be irradiated to different fluence levels, the first from 0.5 to 4 dpa and the second from 4 to 7 dpa. AGC-1 is the first of the six capsules designed for ATR and will focus on the prismatic fluence range.

  17. Modeling of Irradiation Hardening of Polycrystalline Materials

    SciTech Connect

    Li, Dongsheng; Zbib, Hussein M.; Garmestani, Hamid; Sun, Xin; Khaleel, Mohammad A.

    2011-09-14

    High energy particle irradiation of structural polycrystalline materials usually produces irradiation hardening and embrittlement. The development of predict capability for the influence of irradiation on mechanical behavior is very important in materials design for next generation reactors. In this work a multiscale approach was implemented to predict irradiation hardening of body centered cubic (bcc) alpha-iron. The effect of defect density, texture and grain boundary was investigated. In the microscale, dislocation dynamics models were used to predict the critical resolved shear stress from the evolution of local dislocation and defects. In the macroscale, a viscoplastic self-consistent model was applied to predict the irradiation hardening in samples with changes in texture and grain boundary. This multiscale modeling can guide performance evaluation of structural materials used in next generation nuclear reactors.

  18. Production of modified starches by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Kang, Il-Jun; Byun, Myung-Woo; Yook, Hong-Sun; Bae, Chun-Ho; Lee, Hyun-Soo; Kwon, Joong-Ho; Chung, Cha-Kwon

    1999-04-01

    As a new processing method for the production of modified starch, gamma irradiation and four kinds of inorganic peroxides were applied to commercial corn starch. The addition of inorganic peroxides without gamma irradiation or gamma irradiation without the addition of inorganic peroxides effectively decreased initial viscosity, but did not sufficiently keep viscosity stable. The combination of adding ammonium persulfate (APS) and gamma irradiation showed the lowest initial viscosity and the best stability out of the tested four kinds of inorganic peroxides. Among the tested mixing methods of APS, soaking was found to be more effective than dry blending or spraying. Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability became feasible by the control of gamma irradiation dose levels and the amount of added APS to starch.

  19. Li + grafting of ion irradiated polyethylene

    NASA Astrophysics Data System (ADS)

    Švorčík, V.; Rybka, V.; Vacík, J.; Hnatowicz, V.; Öchsner, R.; Ryssel, H.

    1999-02-01

    Foils of oriented polyethylene (PE) were irradiated with 63 keV Ar + and 155 keV Xe + ions to different fluences at room temperature and then doped from water solution of LiCl. The as irradiated and irradiated plus doped samples were examined by IR, EPR and neutron depth profiling (NDP) technique. The sheet resistance was also measured by the standard two points method. After Li salt doping of ion modified layer of PE, a reaction between degraded macromolecules and Li occur and thus a new chemical structure C-Li + is formed. Owing to the presence of these cations on the polymer chain, the irradiated plus doped layer exhibits higher electric conductivity compared to as-irradiated ones.

  20. Relief of vasospasm by intravascular ultraviolet irradiation

    NASA Astrophysics Data System (ADS)

    Nakai, Kanji; Morimoto, Yuji; Ito, Hirotaka; Kominami, Kimito; Matsuo, Hirotaka; Arai, Tsunenori; Kikuchi, Makoto

    1998-05-01

    We investigated the photovasorelaxation with intravascular transluminal irradiation using in vivo model. A 2.5 Fr. catheter was inserted in the femoral artery of a rabbit under anesthesia. A 400 micrometers diameter quartz fiber was inserted through the catheter. The catheter was withdrawn from the distal end to the proximal end of the exposed femoral artery without laser irradiation in order to observe the mechanical dilation by the procedure. The femoral artery lumen was irradiated by a Helium-Cadmium(He-Cd) laser (wavelength; 325 nm) with 8 mW through the fiber during 30 s. We carried out that the laser irradiation produced vasorelaxation (185% on the average) compared with mechanical vasodilation (150% on the average) with angiography. The results suggest that intravascular transluminal irradiation with low-power UV laser might be applicable to the relief of acute arterial vasospasm.

  1. Effects of irradiation on mandibular scintigraphy

    SciTech Connect

    Aitasalo, K.; Ruotsalainen, P.

    1985-11-01

    Technetium-99m methylene diphosphonate (Sn) scintigraphy with computer analysis was used to investigate alterations in the pathophysiology of the normal mandible and the pathologic mandible during and after irradiation. Slight but significant elevations of uptake levels were recorded as an early effect of irradiation. The elevations correlated with the duration of treatment and normalized over a follow-up period of 6 to 12 mo. Increased mandibular metabolism was found during irradiation and in osteomyelitis and osteoradionecrosis of the mandible. Scintigraphy with computer analysis proved a simple and valid method in the evaluation of early irradiation damage and pathophysiologic conditions of the mandible. The method can also be used to predict whether the irradiation damage will become irreversible.

  2. Significance of primary irradiation creep in graphite

    NASA Astrophysics Data System (ADS)

    Erasmus, Christiaan; Kok, Schalk; Hindley, Michael P.

    2013-05-01

    Traditionally primary irradiation creep is introduced into graphite analysis by applying the appropriate amount of creep strain to the model at the initial time-step. This is valid for graphite components that are subjected to high fast neutron flux fields and constant stress fields, but it does not allow for the effect of movement of stress locations around a graphite component during life, nor does it allow primary creep to be applied rate-dependently to graphite components subject to lower fast neutron flux. This paper shows that a differential form of primary irradiation creep in graphite combined with the secondary creep formulation proposed by Kennedy et al. performs well when predicting creep behaviour in experimental samples. The significance of primary irradiation creep in particular in regions with lower flux is investigated. It is shown that in low flux regions with a realistic operating lifetime primary irradiation creep is significant and is larger than secondary irradiation creep.

  3. Microbiological decontamination of natural honey by irradiation

    NASA Astrophysics Data System (ADS)

    Migdał, W.; Owczarczyk, H. B.; K ȩdzia, B.; Hołderna-K ȩdzia, E.; Madajczyk, D.

    2000-03-01

    Degree of microbiological decontamination, organoleptic and physico-chemical properties of natural honeys were investigated after radiation treatment. Seven kinds of honeys were irradiated with the beams of 10 MeV electrons from a 10 kW linear accelerator "Elektronika 10-10" at the dose 10 kGy. It was shown, that after irradiation, the total count of aerobic and anaerobic bacteria and moulds decrease by 99%. The antibiotic value in investigated honeys increased in turn from 1.67 to 2.67 after irradiation. Such factors and parameters of investigated honeys as their consistency, content of water and saccharose, acidity, the diastase and 5-HMF values were not changed significantly after irradiation. Decontamination by irradiation is a process which allows us to obtain high microbiological purity of honeys. It is especially needed, when honeys are used in surgical treatment of injuries and in nutrition of babies with food deficiency.

  4. Pericardial Injury from Mediastinal Irradiation

    PubMed Central

    Kumar, P.P.

    1980-01-01

    The absence of radiation induced cardiac damage during the orthovoltage era, during which period much lower doses of radiation were delivered for mediastinal malignancies due to severe skin reactions, was misinterpreted as cardiac radioresistance. However, with the advent of supervoltage x-rays with skin sparing effect, much higher doses of irradiation have been given for mediastinal malignancies. This has resulted in higher doses of radiation to the heart resulting in various types of radiation induced cardiac damage. The most common site of damage is to the pericardium, resulting in pericardial effusion. The radiographic evidence of radiation induced pericardial effusion starts one to six months prior to signs and symptoms due to it. Most of the asymptomatic radiation induced pericardial effusions resolve spontaneously. The factors which appear to play a role in the development of radiation induced pericardial effusion are discussed. ImagesFigure 1Figure 2 PMID:7392078

  5. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez

    2011-04-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  6. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2012-03-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  7. AFIP-2 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez

    2011-04-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-2 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-2 experiment was fabricated by friction bond (FB) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-2 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results. The safety analyses performed for AFIP-2 are summarized in Table 5 of the following report.

  8. AFIP-3 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-05-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-3 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-3 experiment was fabricated by hot isostatic pressing (HIP) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-3 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results.

  9. AFIP-1 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-05-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-1 was designed to demonstrate the performance of second-generation dispersion fuels at a prototypic scale with a length of 21.5 inches (54.6 cm), width of 2.25 inches (5.75 cm) and a thickness of 0.050 inch (0.13 cm). The experiment was fabricated using commercially standard practices at BWX Technology, Inc. (BWXT). The U-7Mo fuel particles were supplied by the Korean Atomic Energy Research Institute (KAERI) using equipment intended for commercial supply. Two fuel plates were tested that incorporated two different matrix compositions, Al-2Si and Al-4043.1 The following report summarizes the life of the AFIP-1 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results

  10. AFIP-2 Irradiation Summary Report

    SciTech Connect

    Danielle M Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-05-01

    The Advanced Test Reactor (ATR) Full size plate In center flux trap Position (AFIP) experiment AFIP-2 was designed to evaluate the performance of monolithic fuels at a prototypic scale of 2.25 inches x 21.5 inches x 0.050 inches (5.75 cm x 54.6 cm x 0.13cm). The AFIP-2 experiment was fabricated by friction bond (FB) and consists of two plates, one with a zirconium (Zr) diffusion barrier and one with a silicon (Si) enhanced fuel/clad interface1,2. The following report summarizes the life of the AFIP-2 experiment through end of irradiation, including a brief description of the safety analysis, as-run neutronic analysis results, hydraulic testing results, and thermal analysis results. The safety analyses performed for AFIP-2 are summarized in Table 5 of the following report.

  11. RERTR-7 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; M. A. Lillo; G. S. Chang; G. A. Roth; N. E. Woolstenhulme; D. M. Wachs

    2011-12-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-7A, was designed to test several modified fuel designs to target fission densities representative of a peak low enriched uranium (LEU) burnup in excess of 90% U-235 at peak experiment power sufficient to generate a peak surface heat flux of approximately 300 W/cm2. The RERTR-7B experiment was designed as a high power test of 'second generation' dispersion fuels at peak experiment power sufficient to generate a surface heat flux on the order of 230 W/cm2.1 The following report summarizes the life of the RERTR-7A and RERTR-7B experiments through end of irradiation, including as-run neutronic analyses, thermal analyses and hydraulic testing results.

  12. RERTR-10 Irradiation Summary Report

    SciTech Connect

    D. M. Perez

    2011-05-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-10 was designed to further test the effectiveness of modified fuel/clad interfaces in monolithic fuel plates. The experiment was conducted in two campaigns: RERTR-10A and RERTR-10B. The fuel plates tested in RERTR-10A were all fabricated by Hot Isostatic Pressing (HIP) and were designed to evaluate the effect of various Si levels in the interlayer and the thickness of the Zr interlayer (0.001”) using 0.010” and 0.020” nominal foil thicknesses. The fuel plates in RERTR-10B were fabricated by Friction Bonding (FB) with two different thickness Si layers and Nb and Zr diffusion barriers.1 The following report summarizes the life of the RERTR-10A/B experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  13. Variability of solar ultraviolet irradiance

    NASA Technical Reports Server (NTRS)

    Pap, J. M.; Donnelly, R. F.; Hudson, H. S.; Rottman, G. J.; Willson, R. C.

    1991-01-01

    A model of solar Lyman alpha irradiance developed by multiple linear regression analysis, including the daily values and 81-day running means of the full disk equivalent width of the Helium line at 1083 nm, predicts reasonably well both the short- and long-term variations observed in Lyman alpha. In contrast, Lyman alpha models calculated from the 10.7-cm radio flux overestimate the observed variations in the rising portion and maximum period of solar cycle, and underestimates them during solar minimum. Models are shown of Lyman alpha based on the He-line equivalent width and 10.7-cm radio flux for those time intervals when no satellite observations exist, namely back to 1974 and after April 1989, when the measurements of the Solar Mesosphere Satellite were terminated.

  14. Rapid differentiation between gamma-irradiated and non irradiated potato tubers

    NASA Astrophysics Data System (ADS)

    Jona, Roberto; Fronda, Anna

    The use of gamma irradiation as commercial method for the preservation of fruits and vegetables calls for methods of differentiation between irradiated and non-irradiated foodstuffs. In a previous research, the polysaccharidic content of cell walls of irradiated tissue has been investigated, but it required rather long time to reach the result. A method devised to ascertain the vitality of cells has been applied to distinguish irradiated from non-irradiated potato tubers. 500 mg of tissue excised from tubers have been infiltrated with tetrazolium chloride 0.6% in phosphate buffer, pH 7.4. After 15 hrs of incubation at 30°C the treated tissues have been extracted with 95% ethanol whose O.D. has been measured at 530 mμ wavelength. The colour intensity of the alcohol allowed a very clearcut recognition of the irradiated tubers.

  15. Irradiation creep of dispersion strengthened copper alloy

    SciTech Connect

    Pokrovsky, A.S.; Barabash, V.R.; Fabritsiev, S.A.

    1997-04-01

    Dispersion strengthened copper alloys are under consideration as reference materials for the ITER plasma facing components. Irradiation creep is one of the parameters which must be assessed because of its importance for the lifetime prediction of these components. In this study the irradiation creep of a dispersion strengthened copper (DS) alloy has been investigated. The alloy selected for evaluation, MAGT-0.2, which contains 0.2 wt.% Al{sub 2}O{sub 3}, is very similar to the GlidCop{trademark} alloy referred to as Al20. Irradiation creep was investigated using HE pressurized tubes. The tubes were machined from rod stock, then stainless steel caps were brazed onto the end of each tube. The creep specimens were pressurized by use of ultra-pure He and the stainless steel caps subsequently sealed by laser welding. These specimens were irradiated in reactor water in the core position of the SM-2 reactors to a fluence level of 4.5-7.1 x 10{sup 21} n/cm{sup 2} (E>0.1 MeV), which corresponds to {approx}3-5 dpa. The irradiation temperature ranged from 60-90{degrees}C, which yielded calculated hoop stresses from 39-117 MPa. A mechanical micrometer system was used to measure the outer diameter of the specimens before and after irradiation, with an accuracy of {+-}0.001 mm. The irradiation creep was calculated based on the change in the diameter. Comparison of pre- and post-irradiation diameter measurements indicates that irradiation induced creep is indeed observed in this alloy at low temperatures, with a creep rate as high as {approx}2 x 10{sup {minus}9}s{sup {minus}1}. These results are compared with available data for irradiation creep for stainless steels, pure copper, and for thermal creep of copper alloys.

  16. Feasibility Trial of Partial Breast Irradiation With Concurrent Dose-Dense Doxorubicin and Cyclophosphamide in Early-Stage Breast Cancer

    PubMed Central

    Zellars, Richard C.; Stearns, Vered; Frassica, Deborah; Asrari, Fariba; Tsangaris, Theodore; Myers, Lee; DiPasquale, Shirley; Lange, Julie R.; Jacobs, Lisa K.; Emens, Leisha A.; Armstrong, Deborah K.; Fetting, John H.; Garrett-Mayer, Elizabeth; Davidson, Nancy E.; Wolff, Antonio C.

    2016-01-01

    Purpose Anthracyclines and concurrent whole-breast irradiation result in prohibitive cutaneous toxicity. We hypothesized that anthracycline-based chemotherapy and concurrent partial breast irradiation (PBI) is safe and conducted a single-arm feasibility trial testing this hypothesis with dose-dense doxorubicin and cyclophosphamide (ddAC). Patients and Methods Women with T1-2, N0-1 breast cancer with ≥ 3 mm lumpectomy margins received PBI (40.5 Gy, 15 daily 2.7-Gy fractions) concurrently with the first two of four cycles of ddAC (60 and 600 mg/m2 of doxorubicin and cyclophosphamide, respectively, every 14 days with colony-stimulating support). Primary end points were local and systemic toxicity. Additional systemic therapy was given at the physician's discretion. Results Twenty-seven patients enrolled between November 2004 and January 2007, but two patients did not receive protocol therapy (one found with additional local disease and one withdrew consent). Twenty-five women completed all planned PBI. Four (16%) of 25 did not complete all ddAC (febrile neutropenia [FN], n = 2; diverticulitis and neutropenia, n = 1; and social/economic reasons, n = 1). Four among the remaining 21 who completed all ddAC had a cycle delayed (FN, n = 1; acute respiratory illness, n = 1; foot blisters, n = 1; perianal dermatitis, n = 1). There was no grade 3 to 4 anemia or thrombocytopenia. Grade 3 nonhematologic toxicities (none grade 4) occurred in 28% (seven of 25) of patients (nausea/vomiting, n = 3; stomatitis, n = 2; contralateral breast abscess, n = 1; fatigue, n = 1; and cough/bronchospasms, n = 1). The observed rate of ≥ grade 2 skin toxicity was 0% (0 of 25; one-sided 95% CI, 0% to 11%). Conclusion PBI with concurrent ddAC is feasible, and local/systemic toxicity is acceptable. Larger studies are warranted to assess long-term locoregional control and late toxicities. PMID:19332718

  17. Dental Implants Installed in Irradiated Jaws

    PubMed Central

    Chambrone, L.; Mandia, J.; Shibli, J.A.; Romito, G.A.; Abrahao, M.

    2013-01-01

    The aim of this study was to assess the survival rate of titanium implants placed in irradiated jaws. MEDLINE, EMBASE, and CENTRAL were searched for studies assessing implants that had been placed in nongrafted sites of irradiated patients. Random effects meta-analyses assessed implant loss in irradiated versus nonirradiated patients and in irradiated patients treated with hyperbaric oxygen (HBO) therapy. Of 1,051 potentially eligible publications, 15 were included. A total of 10,150 implants were assessed in the included studies, and of these, 1,689 (14.3%) had been placed in irradiated jaws. The mean survival rate in the studies ranged from 46.3% to 98.0%. The pooled estimates indicated a significant increase in the risk of implant failure in irradiated patients (risk ratio: 2.74; 95% confidence interval: 1.86, 4.05; p < .00001) and in maxillary sites (risk ratio: 5.96; 95% confidence interval: 2.71, 13.12; p < .00001). Conversely, HBO therapy did not reduce the risk of implant failure (risk ratio: 1.28; 95% confidence interval: 0.19, 8.82; p = .80). Radiotherapy was linked to higher implant failure in the maxilla, and HBO therapy did not improve implant survival. Most included publications reported data on machined implants, and only 3 studies on HBO therapy were included. Overall, implant therapy appears to be a viable treatment option for reestablishing adequate occlusion and masticatory conditions in irradiated patients. PMID:24158336

  18. AGR-1 Irradiation Experiment Test Plan

    SciTech Connect

    John T. Maki

    2009-10-01

    This document presents the current state of planning for the AGR-1 irradiation experiment, the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment will be irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). The test will contain six independently controlled and monitored capsules. Each capsule will contain a single type, or variant, of the AGR coated fuel. The irradiation is planned for about 700 effective full power days (approximately 2.4 calendar years) with a time-averaged, volume-average temperature of approximately 1050 °C. Average fuel burnup, for the entire test, will be greater than 17.7 % FIMA, and the fuel will experience fast neutron fluences between 2.4 and 4.5 x 1025 n/m2 (E>0.18 MeV).

  19. Influence of microwave irradiation on enzyme kinetics

    NASA Astrophysics Data System (ADS)

    Pavelkić, V. M.; Stanisavljev, D. R.; Gopčević, K. R.; Beljanski, M. V.

    2009-09-01

    The in vitro effect of 2.45 GHz microwave irradiation on porcine pepsin activity under controlled temperature and absorbed microwave power via kinetic parameters was evaluated. Kinetic study with respect of time of irradiation demonstrated the existence of an inactivation effect of microwaves at pH 2 on pepsin molecule. Bovine serum albumin (BSA)-bromphenol blue (BPB) complex was used as substrate for the assay of pepsin by kinetic method. Depending on absorbed microwave dose, the degree of caused inactivation varies from 39.11 to 45.91% for 5 and 20 min of pepsin MW irradiation, respectively. The V maxapp and K mapp were calculated for low (5 min of MW irradiation) and higher specific absorbed dose (20 min of MW irradiation), as well as for untreated enzyme, from double reciprocal Lineweaver-Burk plot. The effect of microwaves on substrate (BSA-BPB complex) was also investigated. For reaction performed with MW irradiated substrate for 5 min the reaction rate was decreased for 15.15%, while for 20 min of substrate irradiation reaction rate was decreased for 25.52% compared to the control reaction.

  20. Reconstruction of solar UV irradiance since 1974

    NASA Astrophysics Data System (ADS)

    Krivova, N. A.; Solanki, S. K.; Wenzler, T.; Podlipnik, B.

    2009-09-01

    Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the period 1974-2007 by making use of the recently developed empirical extension of the Spectral And Total Irradiance Reconstruction (SATIRE) models employing Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) data. The evolution of the solar photospheric magnetic flux, which is a central input to the model, is described by the magnetograms and continuum images recorded at the Kitt Peak National Solar Observatory between 1974 and 2003 and by the Michelson Doppler Imager instrument on SOHO since 1996. The reconstruction extends the available observational record by 1.5 solar cycles. The reconstructed Ly-α irradiance agrees well with the composite time series by Woods et al. (2000). The amplitude of the irradiance variations grows with decreasing wavelength and in the wavelength regions of special interest for studies of the Earth's climate (Ly-α and oxygen absorption continuum and bands between 130 and 350 nm) is 1-2 orders of magnitude stronger than in the visible or if integrated over all wavelengths (total solar irradiance).

  1. Rapid detection of irradiated frozen hamburgers

    NASA Astrophysics Data System (ADS)

    Delincée, Henry

    2002-03-01

    DNA comet assay can be employed as a rapid and inexpensive screening test to check whether frozen ground beef patties (hamburgers) have been irradiated as a means to increase their safety by eliminating pathogenic bacteria, e.g. E. coli O157:H7. Such a detection procedure will provide an additional check on compliance with existing regulations, e.g. enforcement of labelling and rules in international trade. Frozen ready prepared hamburgers from the market place were `electron irradiated' with doses of 0, 1.3, 2.7, 4.5 and 7.2kGy covering the range of potential commercial irradiation. DNA fragmentation in the hamburgers was made visible within a few hours using the comet assay, and non-irradiated hamburgers could be easily discerned from the irradiated ones. Even after 9 months of frozen storage, irradiated hamburgers could be identified. Since DNA fragmentation may also occur with other food processes (e.g. temperature abuse), positive screening tests shall be confirmed using a validated method to specifically prove an irradiation treatment, e.g. EN 1784 or EN 1785.

  2. Spectroscopic investigation of UV irradiated enzymes

    SciTech Connect

    Ware, D.L.; Hibbard, L.B. )

    1993-01-01

    Trptophan (Trp) undergoes photolysis when exposed to light in the near UV region. The enzyme systems horse liver alcohol dehydrogenase (HLAD) and glyceraldehyde 3-phosphate dehydrogenase (G3PDH), which contain two and three Trps respectively, were chosen for analysis of Trp photolysis. Aqueous solutions of HLAD and G3PDH were irradiated at either 295 or 335nm with a xenon lamp. Tryptophan fluorescence was monitored at half hour intervals for two hours in the case of HLAD and one hour in the case of G3PDH. The decrease in fluorescence from 295 irradiation was compared to the fluorescence decrease from 335 irradiation and was found to be similar for both the HLAD and G3PDH samples irradiated at 295nm and for both samples irradiated at 335nm. It was found that, for HLAD, the 295 irradiation caused a decrease in fluorescence of 90% as compared to a decrease of only 12% of 335nm. Enzymatic assays were then performed to determine the enzymatic activity before and after irradiation.

  3. Urban tree influences on ultraviolet irradiance

    NASA Astrophysics Data System (ADS)

    Heisler, Gordon M.; Grant, Richard H.; Gao, Wei

    2002-01-01

    Many of the effects of ultraviolet radiation (UVR) on people and their environment--damage to various materials, survival of insects and microbial pathogens, growth of vegetation, and adverse or beneficial effects on human health--are modified by the presence of trees. Human epidemiological investigations generally consider exposure as given by indices of UVR irradiance on horizontal surfaces in the open. Though many people are exposed to UVR while reclining at a beach or swimming pool, thus experiencing irradiance on essentially horizontal surfaces in the open, exposure to UVR during daily routines in urban areas may also be important in affecting human health. Tree influences on UVR irradiance, particularly in the UVB, can differ substantially from influences on the visible portion of the solar spectrum. Trees greatly reduce UVB irradiance in their shade when they obscure both the sun and sky. Where trees obscure the sun but leave much of the sky in view, UVB irradiance will be greater than suggested by the visible shadow. In small sunny areas near trees that block much of the sky from view, UVB irradiance is reduced substantially, whereas visible irradiance may be nearly as great or slightly greater than in the open.

  4. Rheological changes in irradiated chicken eggs

    NASA Astrophysics Data System (ADS)

    Ferreira, Lúcia F. S.; Del Mastro, Nélida L.

    1998-06-01

    Pathogenic bacteria may cause foodborne illnesses. Humans may introduce pathogens into foods during production, processing, distribution and or preparation. Some of these microorganisms are able to survive conventional preservation treatments. Heat pasteurization, which is a well established and satisfactory means of decontamination/disinfection of liquid foods, cannot efficiently achieve a similar objective for solid foods. Extensive work carried out worldwide has shown that irradiation is efficient in eradicating foodborne pathogens like Salmonella spp. that can contaminate poultry products. In this work Co-60 gamma irradiation was applied to samples of industrial powder white, yolk and whole egg at doses between 0 and 25 kGy. Samples were rehydrated and the viscosity measured in a Brookfield viscosimeter, model DV III at 5, 15 and 25°C. The rheological behaviour among the various kinds of samples were markedly different. Irradiation with doses up to 5 kGy, known to reduced bacterial contamination to non-detectable levels, showed almost no variation of viscosity of irradiated egg white samples. On the other hand, whole or yolk egg samples showed some changes in rheological properties depending on the dose level, showing the predominance of whether polimerization or degradation as a result of the irradiation. Additionally, irradiation of yolk egg powder reduced yolk color as a function of the irradiation exposure implemented. The importance of these results are discussed in terms of possible industrial applications.

  5. Irradiation exposure modulates central opioid functions

    SciTech Connect

    Dougherty, P.M.; Dafny, N.

    1987-11-01

    Exposure to low doses of gamma irradiation results in the modification of both the antinociceptive properties of morphine and the severity of naloxone-precipitated withdrawal in morphine-dependent rats. To better define the interactions between gamma irradiation and these opiate-mediated phenomena, dose-response studies were undertaken of the effect of irradiation on morphine-induced antinociception, and on the naloxone-precipitated withdrawal syndrome of morphine-dependent rats. In addition, electrophysiologic studies were conducted in rats after irradiation exposure and morphine treatment correlating with the behavioral studies. The observations obtained demonstrated that the antinociceptive effects of morphine as well as naloxone-precipitated withdrawal were modified in a dose-dependent manner by irradiation exposure. In addition, irradiation-induced changes in the evoked responses obtained from four different brain regions demonstrated transient alterations in both baseline and morphine-treated responses that may reflect the alterations observed in the behavioral paradigms. These results suggest that the effects of irradiation on opiate activities resulted from physiologic alterations of central endogenous opioid systems due to alterations manifested within peripheral targets.

  6. [Near infrared light irradiator using halogen lamp].

    PubMed

    Ide, Yasuo

    2012-07-01

    The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer. PMID:22860296

  7. Influence of irradiation on stored platelets

    SciTech Connect

    Moroff, G.; George, V.M.; Siegl, A.M.; Luban, N.L.

    1986-09-01

    Platelet concentrates intended for transfusion to immunosuppressed patients are irradiated to minimize transfusion-induced graft-versus-host disease. Because few reports describe how irradiation influences stored platelets, the authors studied whether 5000 rad of gamma irradiation, the maximum dose currently used clinically, altered platelets in vitro. Platelet concentrates were stored for either 1 day or 5 days in plastic (PL 732) containers before gamma irradiation. One unit of a pair of identical platelet concentrates was irradiated; the second unit served as a control. Irradiation did not alter platelet morphology, mean platelet volume, expression of platelet-factor-3 activity, response to hypotonic stress, extent of discharge of lactate dehydrogenase, release of beta-thromboglobulin, formation of thromboxane B2, nor the ability to undergo synergistic aggregation. The lack of any substantial change was observed whether the platelet concentrates were stored initially for either 1 day or 5 days. These results suggest that stored platelets are not altered deleteriously by irradiation with 5000 rad.

  8. The Next Spaceflight Solar Irradiance Sensor: TSIS

    NASA Astrophysics Data System (ADS)

    Kopp, Greg; Pilewskie, Peter; Richard, Erik

    2016-05-01

    The Total and Spectral Solar Irradiance Sensor (TSIS) will continue measurements of the solar irradiance with improved accuracies and stabilities over extant spaceflight instruments. The two TSIS solar-observing instruments include the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) for measuring total- and spectral- solar-irradiance, respectively. The former provides the net energy powering the Earth’s climate system while the latter helps attribute where that energy is absorbed by the Earth’s atmosphere and surface. Both spaceflight instruments are assembled and being prepared for integration on the International Space Station. With operations commencing in late 2017, the TSIS is intended to overlap with NASA’s ongoing SOlar Radiation and Climate Experiment (SORCE) mission, which launched in 2003 and contains the first versions of both the TIM and SIM instruments, as well as with the TSI Calibration Transfer Experiment (TCTE), which began total solar irradiance measurements in 2013. We summarize the TSIS’s instrument improvements and intended solar-irradiance measurements.

  9. AGC-1 Post Irradiation Examination Status

    SciTech Connect

    David Swank

    2011-09-01

    The Next Generation Nuclear Plant (NGNP) Graphite R&D program is currently measuring irradiated material property changes in several grades of nuclear graphite for predicting their behavior and operating performance within the core of new Very High Temperature Reactor (VHTR) designs. The Advanced Graphite Creep (AGC) experiment consisting of six irradiation capsules will generate this irradiated graphite performance data for NGNP reactor operating conditions. All six AGC capsules in the experiment will be irradiated in the Advanced Test Reactor (ATR), disassembled in the Hot Fuel Examination Facility (HFEF), and examined at the INL Research Center (IRC) or Oak Ridge National Laboratory (ORNL). This is the first in a series of status reports on the progress of the AGC experiment. As the first capsule, AGC1 was irradiated from September 2009 to January 2011 to a maximum dose level of 6-7 dpa. The capsule was removed from ATR and transferred to the HFEF in April 2011 where the capsule was disassembled and test specimens extracted from the capsules. The first irradiated samples from AGC1 were shipped to the IRC in July 2011and initial post irradiation examination (PIE) activities were begun on the first 37 samples received. PIE activities continue for the remainder of the AGC1 specimen as they are received at the IRC.

  10. Effects of carbon ion irradiation and X-ray irradiation on the ubiquitylated protein accumulation

    PubMed Central

    ISOZAKI, TETSURO; FUJITA, MAYUMI; YAMADA, SHIGERU; IMADOME, KAORI; SHOJI, YOSHIMI; YASUDA, TAKESHI; NAKAYAMA, FUMIAKI; IMAI, TAKASHI; MATSUBARA, HISAHIRO

    2016-01-01

    C-ion radiotherapy is associated with improved local control and survival in several types of tumors. Although C-ion irradiation is widely reported to effectively induce DNA damage in tumor cells, the effects of irradiation on proteins, such as protein stability or degradation in response to radiation stress, remain unknown. We aimed to compare the effects of C-ion and X-ray irradiation focusing on the cellular accumulation of ubiquitylated proteins. Cells from two human colorectal cancer cell lines, SW620 and SW480, were subjected to C-ion or X-ray irradiation and determination of ubiquitylated protein levels. High levels of ubiquitylated protein accumulation were observed in the C-ion-irradiated SW620 with a peak at 3 Gy; the accumulation was significantly lower in the X-ray-irradiated SW620 at all doses. Enhanced levels of ubiquitylated proteins were also detected in C-ion or X-ray-irradiated SW480, however, those levels were significantly lower than the peak detected in the C-ion-irradiated SW620. The levels of irradiation-induced ubiquitylated proteins decreased in a time-dependent manner, suggesting that the proteins were eliminated after irradiation. The treatment of C-ion-irradiated SW620 with a proteasome inhibitor (epoxomicin) enhanced the cell killing activity. The accumulated ubiquitylated proteins were co-localized with γ-H2AX, and with TP53BP1, in C-ion-irradiated SW620, indicating C-ion-induced ubiquitylated proteins may have some functions in the DNA repair system. Overall, we showed C-ion irradiation strongly induces the accumulation of ubiquitylated proteins in SW620. These characteristics may play a role in improving the therapeutic ratio of C-ion beams; blocking the clearance of ubiquitylated proteins may enhance sensitivity to C-ion radiation. PMID:27175736

  11. Effects of carbon ion irradiation and X-ray irradiation on the ubiquitylated protein accumulation.

    PubMed

    Isozaki, Tetsuro; Fujita, Mayumi; Yamada, Shigeru; Imadome, Kaori; Shoji, Yoshimi; Yasuda, Takeshi; Nakayama, Fumiaki; Imai, Takashi; Matsubara, Hisahiro

    2016-07-01

    C-ion radiotherapy is associated with improved local control and survival in several types of tumors. Although C-ion irradiation is widely reported to effectively induce DNA damage in tumor cells, the effects of irradiation on proteins, such as protein stability or degradation in response to radiation stress, remain unknown. We aimed to compare the effects of C-ion and X-ray irradiation focusing on the cellular accumulation of ubiquitylated proteins. Cells from two human colorectal cancer cell lines, SW620 and SW480, were subjected to C-ion or X-ray irradiation and determination of ubiquitylated protein levels. High levels of ubiquitylated protein accumulation were observed in the C-ion-irradiated SW620 with a peak at 3 Gy; the accumulation was significantly lower in the X-ray-irradiated SW620 at all doses. Enhanced levels of ubiquitylated proteins were also detected in C-ion or X-ray-irradiated SW480, however, those levels were significantly lower than the peak detected in the C-ion-irradiated SW620. The levels of irradiation-induced ubiquitylated proteins decreased in a time-dependent manner, suggesting that the proteins were eliminated after irradiation. The treatment of C-ion-irradiated SW620 with a proteasome inhibitor (epoxomicin) enhanced the cell killing activity. The accumulated ubiquitylated proteins were co-localized with γ-H2AX, and with TP53BP1, in C-ion-irradiated SW620, indicating C-ion-induced ubiquitylated proteins may have some functions in the DNA repair system. Overall, we showed C-ion irradiation strongly induces the accumulation of ubiquitylated proteins in SW620. These characteristics may play a role in improving the therapeutic ratio of C-ion beams; blocking the clearance of ubiquitylated proteins may enhance sensitivity to C-ion radiation. PMID:27175736

  12. Neutron irradiation creep in stainless steel alloys

    NASA Astrophysics Data System (ADS)

    Schüle, Wolfgang; Hausen, Hermann

    1994-09-01

    Irradiation creep elongations were measured in the HFR at Petten on AMCR steels, on 316 CE-reference steels, and on US-316 and US-PCA steels varying the irradiation temperature between 300°C and 500°C and the stress between 25 and 300 MPa. At the beginning of an irradiation a type of "primary" creep stage is observed for doses up to 3-5 dpa after which dose the "secondary" creep stage begins. The "primary" creep strain decreases in cold-worked steel materials with decreasing stress and decreasing irradiation temperature achieving also negative creep strains depending also on the pre-treatment of the materials. These "primary" creep strains are mainly attributed to volume changes due to the formation of radiation-induced phases, e.g. to the formation of α-ferrite below about 400°C and of carbides below about 700°C, and not to irradiation creep. The "secondary" creep stage is found for doses larger than 3 to 5 dpa and is attributed mainly to irradiation creep. The irradiation creep rate is almost independent of the irradiation temperature ( Qirr = 0.132 eV) and linearly dependent on the stress. The total creep elongations normalized to about 8 dpa are equal for almost every type of steel irradiated in the HFR at Petten or in ORR or in EBR II. The negative creep elongations are more pronounced in PCA- and in AMCR-steels and for this reason the total creep elongation is slightly smaller at 8 dpa for these two steels than for the other steels.

  13. Raman spectroscopy of C-irradiated graphite

    SciTech Connect

    Hembree, D.M. Jr.; Pedraza, D.F.; Romanoski, G.R.; Withrow, S.P.; Annis, B.K.

    1994-09-01

    Highly oriented pyrolytic graphite samples were irradiated with C{sup +} ions at 35 keV in a direction normal to the basal plane and subsequently annealed up to 1373 K. Substantial surface topography changes were observed at fluences of 5 {times} 10{sup 18} ions/m{sup 2} and higher using scanning electron and atomic force microscopies. Intricate networks of surface cracks and ridges developed after high dose implantation. A systematic study of the irradiation effects was conducted using Raman spectroscopy. Microstructural changes in irradiated regions were first detected at a dose of 1 {times} 10{sup 17} ions/m{sup 2} through the appearance of the Raman D-line at {approx}1360 cm{sup {minus}1}. The intensity of this line increases while that of the Raman G-line at 1580 cm{sup {minus}1} decreases as the irradiation dose is increased or the irradiation temperature is decreased. After irradiation at 280K to a fluence of 5 {times} 10{sup 19} ions/m{sup 2} or higher the first order spectrum exhibits one single line at a wavelength intermediate between the D- and G-lines. Damage recovery upon thermal annealing depends not only on the initial damage state but also on the annealing temperature sequence. Samples irradiated to a damage level where two distinct Raman peaks are no longer resolvable exhibited upon direct annealing at a high temperature two distinct Raman lines. By contrast, pre-annealing these highly irradiated specimens at lower temperatures produced less pronounced changes in the Raman spectra. Pre-annealing appears to stabilize damage structures that are more resistant to high-temperature annealing than those induced by irradiation.

  14. Influences of Microwave Irradiation on Environment

    NASA Astrophysics Data System (ADS)

    Murakami, H.; Abe, Y.; Iwata, T.; Kudo, I.; Saito, K.; Okuda, T.

    2004-12-01

    An experimental facility to evaluate the long-duration influence of microwave to environment, a so-called long duration microwave exposure facility (LDMEF), was constructed in Tsukuba in 1994, and so far irradiation tests on plants accumulated over 40,000 hours have been conducted with the aid of 2.45 GHz magnetron. The LDMEF consists of a pair of outdoor electromagnetically isolated areas, one under the influence of microwave irradiation with a 500 W magnetron and one without microwave irradiation. The growth rates of plants in both areas were compared and evaluated with the experimental data for the temperature distribution in the soil and power distribution of microwave. Although any appreciable influence of microwave was not noticed in the power density less than 10 mW/cm2 , the experimental results showed a significant growth rate enhancement when the power density became over 10 mW/cm2 . However, the growth was rather depressed when the power density increased over 15 mW/cm2 . These effects are well explained by the temperature and moisture in the soil which are also under an appreciable influence of microwave irradiation [1,2]. In this context, we newly constructed an indoor irradiation facility, in which the growth conditions of plants under a constant soil temperature can be maintained. In addition, irradiation with a 5.8 GHz magnetron will be conducted in the new facility. In parallel to a series of indoor and outdoor irradiation tests on plants, the influence of microwave irradiation on the growth pattern of albino mouse will be conducted. This experiment will be the first experimental evaluation for the influence of microwave irradiation on animals.

  15. RERTR-12 Insertion 2 Irradiation Summary Report

    SciTech Connect

    D. M. Perez; G. S. Chang; D. M. Wachs; G. A. Roth; N. E. Woolstenhulme

    2012-09-01

    The Reduced Enrichment for Research and Test Reactor (RERTR) experiment RERTR-12 was designed to provide comprehensive information on the performance of uranium-molybdenum (U-Mo) based monolithic fuels for research reactor applications.1 RERTR-12 insertion 2 includes the capsules irradiated during the last three irradiation cycles. These capsules include Z, Y1, Y2 and Y3 type capsules. The following report summarizes the life of the RERTR-12 insertion 2 experiment through end of irradiation, including as-run neutronic analysis results, thermal analysis results and hydraulic testing results.

  16. Laser Irradiated Growth of Protein Crystal

    NASA Astrophysics Data System (ADS)

    Adachi, Hiroaki; Takano, Kazufumi; Hosokawa, Youichiroh; Inoue, Tsuyoshi; Mori, Yusuke; Matsumura, Hiroyoshi; Yoshimura, Masashi; Tsunaka, Yasuo; Morikawa, Masaaki; Kanaya, Shigenori; Masuhara, Hiroshi; Kai, Yasushi; Sasaki, Takatomo

    2003-07-01

    We succeeded in the first ever generation of protein crystals by laser irradiation. We call this process Laser Irradiated Growth Technique (LIGHT). Effective crystallization was confirmed by applying an intense femtosecond laser. The crystallization period was dramatically shortened by LIGHT. In addition, protein crystals were obtained by LIGHT from normally uncrystallized conditions. These results indicate that intense femtosecond laser irradiation generates crystal nuclei; protein crystals can then be grown from the nuclei that act as seeds in a supersaturated solution. The nuclei formation is possible primarily due to nonlinear nucleation processes of an intense femtosecond laser with a peak intensity of over a gigawatt (GW).

  17. Infrared spectroscopy study of irradiated PVDF

    SciTech Connect

    Chappa, Veronica; Grosso, Mariela del; Garcia Bermudez, Gerardo; Behar, Moni

    2007-10-26

    The effects induced by 1 MeV/amu ion irradiations were compared to those induced by 4-12 MeV/amu irradiations. Structural analysis with infrared spectroscopy (FTIR) was carried out on PVDF irradiated using C and He beams with different fluences. From these spectra it was observed, as a function of fluence, an overall destruction of the polymer, amorphization of the crystalline regions and the creation of in-chain unsaturations. The track dimensions were determined using a previously developed Monte Carlo simulation code and these results were compared to a semiempirical model.

  18. Investigations on fiberoptic behaviour during gamma irradiation

    NASA Astrophysics Data System (ADS)

    Siehs, J.

    1980-12-01

    The behavior of bulk glasses and fiber optics under gamma irradiation and two types of annealing processes (thermal and optical) were investigated. The samples were irradiated in the thermal column of the TRIGA Mark II reactor. The irradiation induced losses of transmission were measured in a dual beam spectrophotometer. The transmission was measured one hour after reactor shut-down. Thermal annealing was done at 300, 400 and 500 C. Photo bleaching was investigated with a quartz-lamp, an arc-lamp and an UV-laser light.

  19. Apparatus for irradiation with charged particle beams

    SciTech Connect

    Tamura, H.; Ishitani, T.; Shimase, A.

    1984-10-23

    An apparatus according to the present invention for irradiating a specimen with charged particle beams comprises a single charged particle generating source from which the charged particle beams formed of electrons and negative ions, respectively, can be simultaneously derived; a specimen holder on which the specimen is placed; and charged particle irradiation means which is interposed between the charged particle generating source and the specimen holder in order to focus the charged particle beams and to irradiate the surface of the specimen with the focused beams, and which includes at least one magnetic lens and at least one electrostatic lens that are individually disposed.

  20. Hyperparathyroidism following head and neck irradiation

    SciTech Connect

    Rao, S.D.; Frame, B.; Miller, M.J.; Kleerskoper, M.; Block, M.A.; Parfitt, A.M.

    1980-02-01

    A history of head and neck irradiation in childhood or adolescence was found in 22 of 130 patients with primary hyperparathyroidism compared with only 12 of 400 control patients. Among 200 patients with a known history of childhood irradiation, biochemical or surgical evidence of hyperparathyroidism was found in ten, a prevalence of 5%. This is at least 30 times the prevalence of hyperparathyroidism in the general population. The data indicate that head and neck irradiation should be regarded as an important risk factor in the subsequent development of hyperparathyroidism.

  1. Computerized implantology for the irradiated patient.

    PubMed

    Horowitz, Andrew; Orentlicher, Gary; Goldsmith, Douglas

    2009-03-01

    Reconstruction of the irradiated head and neck cancer patient continues to be a challenge. Conventional prosthodontics can be very unpredictable and difficult in these patients. Implant-supported fixed prostheses are good alternatives. It is well-accepted that maxillofacial surgery for the irradiated head and neck cancer patients should be performed in an atraumatic fashion to minimize postoperative complications. We propose the use of computer generated surgical guides and flapless surgery for the placement of dental implants in the irradiated head and neck cancer patient. With these techniques, implants can be placed in an atraumatic, predictable, and accurate manner, according to a prosthetically driven treatment plan. PMID:19231790

  2. Green coffee decontamination by electron beam irradiation

    NASA Astrophysics Data System (ADS)

    Nemtanu, Monica R.; Brasoveanu, Mirela; Grecu, Maria Nicoleta; Minea, R.

    2005-10-01

    Microbiological load of green coffee is a real problem considering that it is extremely sensitive to contamination. Irradiation is a decontamination method for a lot of foodstuffs, being a feasible, very effective and environment friendly one. Beans and ground green coffee were irradiated with electron beams up to 40 kGy. Microbial load, rheological behavior, electron paramagnetic resonance (EPR) and visible spectroscopy were carried out. The results show that electron beam irradiation of green coffee could decontaminate it without severe changes in its properties.

  3. Measuring Degradation Rates Without Irradiance Data

    SciTech Connect

    Pulver, S.; Cormode, D.; Cronin, A.; Jordan, D.; Kurtz, S.; Smith, R.

    2011-02-01

    A method to report PV system degradation rates without using irradiance data is demonstrated. First, a set of relative degradation rates are determined by comparing daily AC final yields from a group of PV systems relative to the average final yield of all the PV systems. Then, the difference between relative and absolute degradation rates is found from a statistical analysis. This approach is verified by comparing to methods that utilize irradiance data. This approach is significant because PV systems are often deployed without irradiance sensors, so the analysis method described here may enable measurements of degradation using data that were previously thought to be unsuitable for degradation studies.

  4. Total body calcium analysis. [neutron irradiation

    NASA Technical Reports Server (NTRS)

    Lewellen, T. K.; Nelp, W. B.

    1974-01-01

    A technique to quantitate total body calcium in humans is developed. Total body neutron irradiation is utilized to produce argon 37. The radio argon, which diffuses into the blood stream and is excreted through the lungs, is recovered from the exhaled breath and counted inside a proportional detector. Emphasis is placed on: (1) measurement of the rate of excretion of radio argon following total body neutron irradiation; (2) the development of the radio argon collection, purification, and counting systems; and (3) development of a patient irradiation facility using a 14 MeV neutron generator. Results and applications are discussed in detail.

  5. Neutron Flux Characterization of Irradiation Holes for Irradiation Test at HANARO

    NASA Astrophysics Data System (ADS)

    Yang, Seong Woo; Cho, Man Soon; Choo, Kee Nam; Park, Sang Jun

    2016-02-01

    The High flux Advanced Neutron Application ReactOr (HANARO) is a unique research reactor in the Republic of Korea, and has been used for irradiation testing since 1998. To conduct irradiation tests for nuclear materials, the irradiation holes of CT and OR5 have been used due to a high fast-neutron flux. Because the neutron flux must be accurately calculated to evaluate the neutron fluence of irradiated material, it was conducted using MCNP. The neutron flux was measured using fluence monitor wires to verify the calculated result. Some evaluations have been conducted, however, more than 20% errors have frequently occurred at the OR irradiation hole, while a good agreement between the calculated and measured data was shown at the CT irradiation hole.

  6. Processing Irradiated Beryllium For Disposal

    SciTech Connect

    T. J. Tranter; R. D. Tillotson; N. R. Mann; G. R. Longhurst

    2005-11-01

    The purpose of this research was to develop a process for decontaminating irradiated beryllium that will allow it to be disposed of through normal radwaste channels. Thus, the primary objectives of this ongoing study are to remove the transuranic (TRU) isotopes to less than 100 nCi/g and remove {sup 60}Co, and {sup 137}Cs, to levels that will allow the beryllium to be contact handled. One possible approach that appears to have the most promise is aqueous dissolution and separation of the isotopes by selected solvent extraction followed by precipitation, resulting in a granular form for the beryllium that may be fixed to prevent it from becoming respirable and therefore hazardous. Beryllium metal was dissolved in nitric and fluorboric acids. Isotopes of {sup 241}Am, {sup 239}Pu, {sup 85}Sr, and {sup 137}Cs were then added to make a surrogate beryllium waste solution. A series of batch contacts was performed with the spiked simulant using chlorinated cobalt dicarbollide (CCD) and polyethylene glycol diluted with sulfone to extract the isotopes of Cs and Sr. Another series of batch contacts was performed using a combination of octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in tributyl phosphate (TBP) diluted with dodecane for extracting the isotopes of Pu and Am. The results indicate that greater than 99.9% removal can be achieved for each isotope with only three contact stages.

  7. Irradiation for locoregionally recurrent, never-irradiated oral cavity cancers

    PubMed Central

    Lok, Benjamin H.; Chin, Christine; Riaz, Nadeem; Ho, Felix; Hu, Man; Hong, Julian C.; Shi, Weiji; Zhang, Zhigang; Sherman, Eric; Wong, Richard J.; Morris, Luc G.; Ganly, Ian; Wolden, Suzanne L.; Rao, Shyam S.; Lee, Nancy Y.

    2016-01-01

    Background The purpose of this study was to report the clinical outcomes and related prognostic factors of patients who underwent radiotherapy (RT) for the treatment of recurrent, never-irradiated oral cavity cancer (recurrent OCC). Methods The records of consecutive patients with nonmetastatic recurrent OCC who presented to and were treated with RT at our institution between 1989 and 2011 were reviewed. The Kaplan–Meier method was used to calculate overall survival (OS). The cumulative incidences of disease-specific death, local failure, regional failure, and distant metastasis were calculated with death as a competing risk. Results One hundred twenty-three patients were identified. Median follow-up for living patients was 54 months and 16 months for all patients. Ninety-one patients had salvage surgery followed by adjuvant RT. Definitive RT was utilized in the remaining 32 patients. The 5-year OS was 40%. The 5-year cumulative incidence of disease-specific death, local failure, regional failure, and distant metastasis was 55%, 34%, 22%, and 20%, respectively. Recurrent T classification and lack of salvage surgery were independently associated with worse disease-specific death and decreased OS, respectively. Subset analysis of patients who underwent salvage surgery demonstrated that age, recurrent T classification, and perineural invasion (PNI) were independently associated with decreased OS; recurrent T classification and thicker tumors were independently associated with worse disease-specific death; and positive/close margins and primary T classification were independently associated with increased local failure. Conclusion In this group of patients with recurrent OCC, clinical outcomes were similar or improved when compared with other recurrent OCC-specific reports. In the salvage surgery subset, tumor thickness and PNI are recurrent pathologic features associated with outcomes that were only previously demonstrated in studies of primary disease. Because of

  8. Surface Irradiances Consistent With CERES-Derived Top-of-Atmosphere Shortwave and Longwave Irradiances

    NASA Technical Reports Server (NTRS)

    Kato, Seiji; Loeb, Norman G.; Rose, Fred G.; Doelling, David R.; Rutan, David A.; Caldwell, Thomas E.; Yu, Lisan; Weller, Robert A.

    2013-01-01

    The estimate of surface irradiance on a global scale is possible through radiative transfer calculations using satellite-retrieved surface, cloud, and aerosol properties as input. Computed top-of-atmosphere (TOA) irradiances, however, do not necessarily agree with observation-based values, for example, from the Clouds and the Earth's Radiant Energy System (CERES). This paper presents amethod to determine surface irradiances using observational constraints of TOA irradiance from CERES. A Lagrange multiplier procedure is used to objectively adjust inputs based on their uncertainties such that the computed TOA irradiance is consistent with CERES-derived irradiance to within the uncertainty. These input adjustments are then used to determine surface irradiance adjustments. Observations by the Atmospheric Infrared Sounder (AIRS), Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), CloudSat, andModerate Resolution Imaging Spectroradiometer (MODIS) that are a part of the NASA A-Train constellation provide the uncertainty estimates. A comparison with surface observations from a number of sites shows that the bias [root-mean-square (RMS) difference] between computed and observed monthlymean irradiances calculated with 10 years of data is 4.7 (13.3) W/sq m for downward shortwave and 22.5 (7.1) W/sq m for downward longwave irradiances over ocean and 21.7 (7.8) W m22 for downward shortwave and 21.0 (7.6) W/sq m for downward longwave irradiances over land. The bias andRMS error for the downward longwave and shortwave irradiances over ocean are decreased from those without constraint. Similarly, the bias and RMS error for downward longwave over land improves, although the constraint does not improve downward shortwave over land. This study demonstrates how synergetic use of multiple instruments (CERES,MODIS, CALIPSO, CloudSat, AIRS, and geostationary satellites) improves the accuracy of surface irradiance computations.

  9. Irradiation-related ischemic heart disease

    SciTech Connect

    Corn, B.W.; Trock, B.J.; Goodman, R.L. )

    1990-04-01

    An expectation for long-term survival has emerged among several groups of cancer patients treated with therapeutic irradiation (eg, Hodgkin's disease, early stage breast cancer). Therefore, the cardiovascular sequelae of thoracic irradiation have recently come under scrutiny. Animal models have demonstrated that cardiac irradiation can directly damage the myocardial microvasculature and can indirectly damage the coronary macrovasculature when coupled with cholesterol feeding. A clear association between thoracic radiotherapy and ischemic heart disease was observed among older clinical studies using radiotherapeutic techniques that are no longer optimal by today's standards. Such a relationship could not be confirmed in modern studies in which treatment factors (such as dose and volume of heart irradiated) were more carefully controlled. 56 references.

  10. Hardness Evolution of Gamma-Irradiated Polyoxymethylene

    NASA Astrophysics Data System (ADS)

    Hung, Chuan-Hao; Harmon, Julie P.; Lee, Sanboh

    2016-04-01

    This study focuses on analyzing hardness evolution in gamma-irradiated polyoxymethylene (POM) exposed to elevated temperatures after irradiation. Hardness increases with increasing annealing temperature and time, but decreases with increasing gamma ray dose. Hardness changes are attributed to defects generated in the microstructure and molecular structure. Gamma irradiation causes a decrease in the glass transition temperature, melting point, and extent of crystallinity. The kinetics of defects resulting in hardness changes follow a first-order structure relaxation. The rate constant adheres to an Arrhenius equation, and the corresponding activation energy decreases with increasing dose due to chain scission during gamma irradiation. The structure relaxation of POM has a lower energy barrier in crystalline regions than in amorphous ones. The hardness evolution in POM is an endothermic process due to the semi-crystalline nature of this polymer.

  11. Damage thresholds in laser irradiated optical materials

    SciTech Connect

    Guignard, F.; Autric, M.; Baudinaud, V.

    1997-12-01

    An experimental study on the damage induced by laser irradiation on different materials, borosilicate glass, fused silicate, moulded and stretched polymethylmethacrylate (PMMA), has been performed. The irradiation source is a 1KJ pulsed cold cathode electron gun preionized TEA CO{sub 2} laser. Damage mechanisms are controlled by the in-depth absorption of the 10,6 {mu}m radiation according to the Beer-Lambert law. The heating of the interaction area gives rise to thermal or thermo-mechanical damages. PMMA is damaged following a boiling process. Stretched PMMA is fractured first, releasing stresses, then boiled like moulded PMMA at higher energy. BK7 crazed after the irradiation due to thermomechanical stresses, silicate melt and vaporized. Optical damages have been characterized by measuring the contrast transfer function through the irradiated samples.

  12. IRRADIATION METHOD OF CONVERTING ORGANIC COMPOUNDS

    DOEpatents

    Allen, A.O.; Caffrey, J.M. Jr.

    1960-10-11

    A method is given for changing the distribution of organic compounds from that produced by the irradiation of bulk alkane hydrocarbons. This method consists of depositing an alkane hydrocarbon on the surface of a substrate material and irradiating with gamma radiation at a dose rate of more than 100,000 rads. The substrate material may be a metal, metal salts, metal oxides, or carbons having a surface area in excess of 1 m/sup 2//g. The hydrocarbons are deposited in layers of from 0.1 to 10 monolayers on the surfaces of these substrates and irradiated. The product yields are found to vary from those which result from the irradiation of bulk hydrocarbons in that there is an increase in the quantity of branched hydrocarbons.

  13. Neoplasia in fast neutron-irradiated beagles

    SciTech Connect

    Bradley, E.W.; Zook; B.C.; Casarett, G.W.

    1981-09-01

    One hundred fifty-one beagle dogs were irradiated with either photons or fast neutrons (15 MeV) to one of three dose-limiting normal tissues - spinal cord, lung, or brain. The radiation was given in four fractions per week for 5 weeks (spinal cord), 6 weeks (lung), 7 weeks (brain) to total doses encompassing those given clinically for cancer management. To date, no nonirradiated dogs or photon-irradiated dogs have developed neoplasms within the irradiated field. Of the neutron-irradiated dogs at risk, the incidence of neoplasia was 15%. The latent period for radiation-induced cancers has varied from 1 to 4 1/2 years at this time in the study.

  14. Neoplasia in fast neutron-irradiated beagles

    SciTech Connect

    Bradley, E.W.; Zook, B.C.; Casarett, G.W.; Deye, J.A.; Adoff, L.M.; Rogers, C.C.

    1981-09-01

    One hundred fifty-one beagle dogs were irradiated with either photons or fast neutrons (15 MeV) to one of three dose-limiting normal tissues--spinal cord, lung, or brain. The radiation was given in four fractions per week for 5 weeks (spinal cord), 6 weeks (lung), or 7 weeks (brain) to total doses encompassing those given clinically for cancer management. To date, no nonirradiated dogs or photon-irradiated dogs have developed any neoplasms. Seven dogs receiving fast neutrons have developed 9 neoplasms within the irradiated field. Of the neutron-irradiated dogs at risk, the incidence of neoplasia was 15%. The latent period for radiation-induced cancers has varied from 1 to 4 1/2 years at this time in the study.

  15. Polymer Morphological Change Induced by Terahertz Irradiation.

    PubMed

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-01-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced "softly," without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10-20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm(2), which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules. PMID:27272984

  16. Thermoluminescence properties of irradiated chickpea and corn

    NASA Astrophysics Data System (ADS)

    Necmeddin Yazici, A.; Bedir, Metin; Bozkurt, Halil; Bozkurt, Hüseyin

    2008-02-01

    A study was carried out to establish a detection method for irradiated chickpea and corn by thermoluminescence (TL) method. The leguminous were packed in polyethylene bags and then the packets were irradiated at room temperature at different doses by 60Co gamma source at 1, 4, 8 and 10 kGy. Minerals extracted from the leguminous were deposited onto a clean aluminum disc and TL intensities of the minerals were measured by TL. It was observed that the extracted samples from both leguminous exhibit good TL Intensity and the TL intensity of glow curves of them increased proportionally to irradiation doses. The TL glow curve of both irradiated leguminous presents a single broad peak below 400 °C. The TL trapping parameters glow peaks were estimated by the additive dose (AD), Tm(Ea)-Tstop and computerized glow curve deconvolution (CGCD) methods. The fading characteristics of glow curves were also recorded up to 6 months.

  17. He-Ne laser extravascular irradiation therapy

    NASA Astrophysics Data System (ADS)

    Chen, Rong; Chen, Huifang; Xie, Shusen; Chen, Yanjiao; Zhang, Yanrong

    2000-10-01

    Based on the study of tissue optics related with the laser irradiation blood therapy, a new treatment method, extravascular low-level laser irradiation therapy (ELLLI) is developed. The veins of 30 patients with cerebrovascular disease combined with diabetes, asthma were treated by He-Ne laser (632.8nm, 25mW) which was delivered by an optics fiber. The fiber was outside the patient's skin and the laser irradiated on the blood vessel perpendicularly. The therapy time was 60 minutes each time and about 7-10 times a course of the treatment. The values of blood sugar, blood- fat and hemorrheology were measured as the effective indexes. After the treatment the effective indexes and the symptoms of the patients were all improved. With the advantages of simplicity and safety (no medical infection), laser extravascular irradiation therapy is likely to be a new medical method for heart brain and other diseases.

  18. Food Irradiation: Is It Safe and Wholesome?

    ERIC Educational Resources Information Center

    Rebus, Shirley

    1990-01-01

    Addresses some of the major issues of food irradiation with respect to safety and wholesomeness, including formation of radiolytic products, effects on nutrients, prevention of food-borne illness, development of radiation-resistant bacteria, and formation of afaltoxins. (Author)

  19. Correlations of solar cycle 22 UV irradiance

    NASA Technical Reports Server (NTRS)

    Floyd, L.; Brueckner, G.; Crane, P.; Prinz, D.; Herring, L.

    1997-01-01

    The solar ultraviolet spectral irradiance monitor (SUSIM) onboard the upper atmosphere research satellite (UARS) is an absolutely calibrated UV spectrometer which has measured the solar spectral irradiance over the wavelengths 115 nm to 410 nm since October 1991. This data set now extends for about six years from near the peak of solar cycle 22, through its minimum, to the initial rise associated with solar cycle 23. Generally, the time series of UV spectral irradiances obtained shows behavior similar to that of other solar activity indices. The conditions on the sun, which can in result in dominant 13.5-day periodicity, are analyzed and illustrated. It is found that any combination of presence or absence of dominant 13.5-day in UV irradiance and solar wind velocity is possible depending entirely on the particular surface distribution and orientation of solar active regions.

  20. Evolution Character Analysis of Total Solar Irradiance

    NASA Astrophysics Data System (ADS)

    Xiang, N. B.

    2013-05-01

    The significant periods of total solar irradiance are 35 days and 26 days in solar cycle 23 and 24, respectively. It is inferred that the solar quasi-rotation periods are 35 days and 26 days in solar cycle 23 and 24, respectively. The value of total solar irradiance in solar cycle 24 minimum should be close to the value of Maunder minimum. On short time scales, sunspots should be the main reason to cause variations of total solar irradiance on the scale of one solar rotation cycle to several months, but not the unique one, and the variations of total solar irradiance are notrelated with the Mg II index on the scale of a few days to one solar rotation cycle.

  1. Wear-resistant polytetrafluoroethylene via electron irradiation

    SciTech Connect

    Blanchet, T.A.; Peng, Y.L.

    1996-06-01

    The sliding wear and friction behavior of irradiation-modified PTFE (by 10 MeV electrons in ambient air) against polished stainless steel is studied. Steady-state wear rate is shown to decrease monotonically by more than three orders of magnitude as the dose of the irradiation is increased from 0 to 30 Mrad. Friction initially increases with increasing dose, reaching a miximum value at 5 Mrad, then decreases with subsequent increases in dose, attaining a value similar to that of unirradiated PTFE at 30 Mrad. Hardness monotonically increases with increasing dose; however, irradiated PTFE was not found to abrasively damage the steel countersurface as many wear-resistant particle-filled PTFE composites do. Wear reduction is accomplished as debris production transforms from that of numerous large plate-like debris for unirradiated PTFE to that of very fine debris for irradiated PTFE. 26 refs., 6 figs.

  2. Total lymphoid irradiation in alloimmunity and autoimmunity

    SciTech Connect

    Strober, S.

    1987-12-01

    Total lymphoid irradiation has been used as an immunosuppressive regimen in autoimmune disease and organ transplantation. The rationale for its use originated from studies of patients with Hodgkin disease, in whom this radiotherapy regimen was noted to induce profound and long-lasting immune suppression and yet was well tolerated, with few long-term side effects. Total lymphoid irradiation is a unique immunosuppressive regimen that produces a selective (and long-lasting) reduction in the number and function of helper T cells and certain subsets of B cells. Conventional immunosuppressive drugs show little selectivity, and their effects are short-lived. The most important aspect of total lymphoid irradiation is the potential for achieving transplantation tolerance and permanent remissions in autoimmune disease in laboratory animals. Attempts are being made to achieve similar goals in humans given total lymphoid irradiation, so that immunosuppressive drugs can be ultimately withdrawn from transplant recipients and patients with lupus nephritis. 28 references.

  3. Gamma irradiation effects in W films

    SciTech Connect

    Claro, Luiz H.; Santos, Ingrid A.; Silva, Cassia F.

    2013-05-06

    Using the van Der Pauw methodology, the surface resistivity of irradiated tungsten films deposited on Silicon substrate was measured. The films were exposed to {gamma} radiation using a isotopic {sup 60}Co source in three irradiation stages attaining 40.35 kGy in total dose. The obtained results for superficial resistivity display a time annealing features and their values are proportional to the total dose.

  4. Blue irradiance intercomparison in the medical field

    NASA Astrophysics Data System (ADS)

    Ferreira, Antonio F. G.

    2012-10-01

    This work presents the results of a blue irradiance intercomparison among industrial laboratories of medical devices companies. This intercomparison aims to support the metrological issues of medical equipment manufactures regarding the blue irradiance infant phototherapy equipment requirements on the international standard IEC 60601-2-50:2000. The results showed a low agreement of participants' measurements according to normalized error criterion. The major explanation for this result is associated to an incorrect equipment choice and long recalibration period.

  5. Neutron Irradiation Resistance of RAFM Steels

    SciTech Connect

    Gaganidze, Ermile; Dafferner, Bernhard; Aktaa, Jarir

    2008-07-01

    The neutron irradiation resistance of the reduced-activation ferritic/martensitic (RAFM) steel EUROFER97 and international reference steels (F82H-mod, OPTIFER-Ia, GA3X and MANET-I) have been investigated after irradiation in the Petten High Flux Reactor up to 16.3 dpa at different irradiation temperatures (250-450 deg. C). The embrittlement behavior and hardening are investigated by instrumented Charpy-V tests with sub-size specimens. Neutron irradiation-induced embrittlement and hardening of EUROFER97 was studied under different heat treatment conditions. Embrittlement and hardening of as-delivered EUROFER97 steel are comparable to those of reference steels. Heat treatment of EUROFER97 at a higher austenitizing temperature substantially improves the embrittlement behaviour at low irradiation temperatures. Analysis of embrittlement vs. hardening behavior of RAFM steels within a proper model in terms of the parameter C={delta}DBTT/{delta}{sigma} indicates hardening-dominated embrittlement at irradiation temperatures below 350 deg. C with 0.17 {<=} C {<=} 0.53 deg. C/MPa. Scattering of C at irradiation temperatures above 400 deg. C indicates non hardening embrittlement. A role of He in a process of embrittlement is investigated in EUROFER97 based steels, that are doped with different contents of natural B and the separated {sup 10}B-isotope (0.008-0.112 wt.%). Testing on small scale fracture mechanical specimens for determination of quasi-static fracture toughness will be also presented in a view of future irradiation campaigns. (authors)

  6. Irradiation autogenous mandibular grafts in primary reconstructions

    SciTech Connect

    Hamaker, R.C.

    1981-07-01

    The procedure, irradiated mandibular autografts, for primary reconstruction, is presented with an immediate success rate of 88%. Eight cases have undergone primary mandibular reconstruction with the tumorous mandible irradiated to 10,000 rads in a single dose. The longest follow-up is 2 3/4 years. The autograft has proven to be an ideal implant. Major resections of the mandible in conjunction with large myocutaneous flaps have been reconstructed utilizing this implant.

  7. Inert matrix fuel behaviour in test irradiations

    NASA Astrophysics Data System (ADS)

    Hellwig, Ch.; Streit, M.; Blair, P.; Tverberg, T.; Klaassen, F. C.; Schram, R. P. C.; Vettraino, F.; Yamashita, T.

    2006-06-01

    Among others, three large irradiation tests on inert matrix fuels have been performed during the last five years: the two irradiation tests IFA-651 and IFA-652 in the OECD Halden Material Test Reactor and the OTTO irradiation in the High Flux Reactor in Petten. While the OTTO irradiation is already completed, the other two irradiations are still ongoing. The objectives of the experiments differ: for OTTO, the focus was on the comparison of different concepts of IMF, i.e. homogeneous fuel versus different types of heterogeneous fuel. In IFA-651, single phase yttria stabilized zirconia (YSZ) doped with Pu is compared with MOX. In IFA-652, the potential of calcia stabilized zirconia (CSZ) as a matrix with and without thoria is evaluated. The design of the three experiments is explained and the current status is reviewed. The experiments show that the homogeneous, single phase YSZ-based or CSZ-based fuel show good and stable irradiation behaviour. It can be said that homogeneous stabilized zirconia based fuel is the most promising IMF concept for an LWR environment. Nevertheless, the fuel temperatures were relatively high due to the low thermal conductivity, potentially leading to high fission gas release, and must be taken into account in the fuel design.

  8. Irradiated Nuclear Fuel Management: Resource Versus Waste

    SciTech Connect

    Nash, Kenneth L.; Lumetta, Gregg J.; Vienna, John D.

    2013-01-01

    Management of irradiated fuel is an important component of commercial nuclear power production. Although it is broadly agreed that the disposition of some fraction of the fuel in geological repositories will be necessary, there is a range of options that can be considered that affect exactly what fraction of material will be disposed in that manner. Furthermore, until geological repositories are available to accept commercial irradiated fuel, these materials must be safely stored. Temporary storage of irradiated fuel has traditionally been conducted in storage pools, and this is still true for freshly discharged fuel. Criticality control technologies have led to greater efficiencies in packing of irradiated fuel into storage pools. With continued delays in establishing permanent repositories, utilities have begun to move some of the irradiated fuel inventory into dry storage. Fuel cycle options being considered worldwide include the once-through fuel cycle, limited recycle in which U and Pu are recycled back to power reactors as mixed oxide fuel, and advance partitioning and transmutation schemes designed to reduce the long term hazards associated with geological disposal from millions of years to a few hundred years. Each of these options introduces specific challenges in terms of the waste forms required to safely immobilize the hazardous components of irradiated fuel.

  9. Total lymphoid irradiation and discordant cardiac xenografts

    SciTech Connect

    Kaplan, E.; Dresdale, A.R.; Diehl, J.T.; Katzen, N.A.; Aronovitz, M.J.; Konstam, M.A.; Payne, D.D.; Cleveland, R.J. )

    1990-01-01

    Total lymphoid irradiation can prolong concordant cardiac xenografts. The effects of total lymphoid irradiation in a discordant xenograft model (guinea pig to rat) were studied with and without adjuvant pharmacologic immunosuppression. Inbred Lewis rats were randomly allocated to one of four groups. Group 1 (n = 6) served as a control group and rats received no immunosuppression. Group 2 (n = 5) received triple-drug therapy that consisted of intraperitoneal azathioprine (2 mg/kg), cyclosporine (20 mg/kg), and methylprednisolone (1 mg/kg) for 1 week before transplantation. Group 3 animals (n = 5) received 15 Gy of total lymphoid irradiation in 12 divided doses over a 3-week period. Group 4 (n = 6) received both triple-drug therapy and total lymphoid irradiation as described for groups 2 and 3. Complement-dependent cytotoxicity assay was performed to determine if a correlation between complement-dependent cytotoxicity and rejection-free interval existed. Rejection was defined as cessation of graft pulsation and was confirmed by histologic test results. Only groups 1 and 2 showed a difference in survival (group 1, 6.9 +/- 1.0 minutes; group 2, 14.2 +/- 2.7 minutes, p = 0.02). Although total lymphoid irradiation did decrease complement-dependent cytotoxicity, linear regression revealed no correlation between complement-dependent cytotoxicity and graft survival (coefficient of correlation, 0.30). Unlike concordant cardiac xenografts, total lymphoid irradiation with or without triple-drug therapy does not prolong graft survival.

  10. Evaluation of irradiation effects on concrete structure

    SciTech Connect

    Kontani, O.; Ishizawa, A.; Maruyama, I.; Takizawa, M.; Sato, O.

    2012-07-01

    In assessing the soundness of irradiated concrete of nuclear power plants operated for more than 30 years, reference levels are employed: 1x10{sup 20} n/cm{sup 2} for fast neutrons and 2x10{sup 10} rad (2x10{sup 5} kGy) for gamma rays. Concrete structures are regarded as sound when the estimated irradiance levels after 60 years of operation are less than the reference levels. The reference levels were obtained from a paper by Hilsdorf. It was found, however, that the test conditions in which data were obtained by the researchers referred in that paper are very different from the irradiation and heat conditions usually found in a Light Water Reactor (LWR), and therefore aren't appropriate for assessing the soundness of irradiated concrete of an LWR. This paper investigates the interactions between radiation and concrete and presents the results of gamma ray irradiation tests on cement paste samples in order to provide a better understanding of the irradiation effects on concrete. (authors)

  11. The effects of irradiation on blood components

    SciTech Connect

    Button, L.N.; DeWolf, W.C.; Newburger, P.E.; Jacobson, M.S.; Kevy, S.V.

    1981-01-01

    The functional properties of formed elements of whole blood were studied following irradiation doses of 500 to 20,000 rads. Irradiated lymphocytes retained only 1.5 per cent of their 3H thymidine uptake after a 5,000-rad exposure and none after 7,500 rads. Red blood cells stored for 21 days and then irradiated with 5,000 rads had the same survival as nonirradiated controls. In contrast, 5,000 rads reduced platelet yields. However, transfused irradiated platelets produced the expected increases in platelet counts and controlled hemostasis in thrombocytopenic patients. After 5,000 rads, granulocytes had normal bacterial killing capacity, chemotactic mobility, and normal superoxide production after high-dose stimulation. Nitroblue tetrazolium reduction and ingestion stimulated by complement opsonized oil droplets were not diminished by 5,000- and 10,000-rad irradiation. The functional qualities of cellular blood components other than lymphocytes are not compromised by 5,000 rads. This irradiation dose may be an effective means of controlling incidence of graft-vs-host disease in immunosuppressed patients.

  12. Irradiation of municipal sludge for agricultural use

    NASA Astrophysics Data System (ADS)

    Ahlstrom, Scott B.

    Research has demonstrated that irradiation is an effective means for reducing pathogens in sewage sludge to levels where sludge reuse in public areas meets criteria for protection of the public health. Complementary research has demonstrated the value of the irradiated sludge in both agronomic and animal science applications. The benefits of sludge application to cropland are well documented. The irradiation process does not increase the extractability and plant uptake of a broad range of nutrients and heavy metals from sludge-amended soils. However, it does eliminate the hazards associated with pathogen contamination when applying sludge to agricultural land. Irradiated sludge has also been evaluated as a supplemental foodstuff for cattle and sheep. The data indicate that products derived from raw sewage may have a substantial nutritive value for ruminant animals. Irradiation of sewage sludge is a practical means of sludge disinfection. Where a highly disinfected sludge is required, it should be considered as a viable sludge management alternative. Evaluation of sludge irradiation technology and its associated costs must be done with consideration of other sludge treatment processes to develop an acceptable sludge management system.

  13. [Light irradiator for various chronic pain].

    PubMed

    Ide, Yasuo

    2014-07-01

    Effects of light upon human tissue are divided into irreversible effects and reversible effects. Irreversible effects can be called as high level laser therapy (HLLT), and reversible effects can be called as low level light therapy (LLLT). Light irradiators for chronic pain act under principle of LLLT. Laser diode, halogen lamp and xenon lamp are used as light sources for light irradiator for various chronic pain. These days, light emitting diode (LED) is used as light source for light irradiator for various kinds of pain. Light irradiators are now divided into portable light weight low power machine and heavy weight, high power machine. In the dental area Nd : YAG laser is using as HLLT tool. But, now there are many reports about Nd : YAG laser used as anesthetic machine. In these reports, topical anesthetic effects of Nd : YAG laser are immediate and with fewer side effects compared with topical anesthetic agents. These effects are explained as LLLT. Halogen lamp and xenon lamp type irradiators were also introduced. MEDILASER SOFT PULSE10, an laser diode type irradiator was withdrawn from the market. PMID:25098134

  14. Solar EUV irradiance for space weather applications

    NASA Astrophysics Data System (ADS)

    Viereck, R. A.

    2015-12-01

    Solar EUV irradiance is an important driver of space weather models. Large changes in EUV and x-ray irradiances create large variability in the ionosphere and thermosphere. Proxies such as the F10.7 cm radio flux, have provided reasonable estimates of the EUV flux but as the space weather models become more accurate and the demands of the customers become more stringent, proxies are no longer adequate. Furthermore, proxies are often provided only on a daily basis and shorter time scales are becoming important. Also, there is a growing need for multi-day forecasts of solar EUV irradiance to drive space weather forecast models. In this presentation we will describe the needs and requirements for solar EUV irradiance information from the space weather modeler's perspective. We will then translate these requirements into solar observational requirements such as spectral resolution and irradiance accuracy. We will also describe the activities at NOAA to provide long-term solar EUV irradiance observations and derived products that are needed for real-time space weather modeling.

  15. Comparison of Deuterium Retention for Ion-irradiated and Neutron-irradiated Tungsten

    SciTech Connect

    Yasuhisa Oya; Masashi Shimada; Makoto Kobayashi; Takuji Oda; Masanori Hara; Hideo Watanabe; Yuji Hatano; Pattrick Calderoni; Kenji Okuno

    2011-12-01

    The behavior of D retention for Fe{sup 2+}-irradiated tungsten with a damage of 0.025-3 dpa was compared with that for neutron-irradiated tungsten with 0.025 dpa. The D{sub 2} thermal desorption spectroscopy (TDS) spectra for Fe{sup 2+}-irradiated tungsten consisted of two desorption stages at 450 and 550 K, while that for neutron-irradiated tungsten was composed of three stages and an addition desorption stage was found at 750 K. The desorption rate of the major desorption stage at 550K increased as the displacement damage increased due to Fe{sup 2+} irradiation increasing. In addition, the first desorption stage at 450K was found only for damaged samples. Therefore, the second stage would be based on intrinsic defects or vacancy produced by Fe{sup 2+} irradiation, and the first stage should be the accumulation of D in mono-vacancy and the activation energy would be relatively reduced, where the dislocation loop and vacancy is produced. The third one was found only for neutron irradiation, showing the D trapping by a void or vacancy cluster, and the diffusion effect is also contributed to by the high full-width at half-maximum of the TDS spectrum. Therefore, it can be said that the D{sub 2} TDS spectra for Fe{sup 2+}-irradiated tungsten cannot represent that for the neutron-irradiated one, indicating that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten is different from that for the ion-irradiated one.

  16. Investigation of the effect of some irradiation parameters on the response of various types of dosimeters to electron irradiation

    NASA Astrophysics Data System (ADS)

    Farah, K.; Kuntz, F.; Kadri, O.; Ghedira, L.

    2004-09-01

    Several undyed and dyed polymer films are commercially available for dosimetry in intense radiation fields, especially for radiation processing of food and sterilisation of medical devices. The effects of temperature during irradiation and post-irradiation stability, on the response of these dosimeters are of importance to operators of irradiation facilities. The present study investigates the effects of temperature during irradiation by 2.2 MeV electrons beam accelerator and post irradiation storage on the response of several types of dosimeter films. All dosimeters showed a significant effect of temperature during irradiation and post-irradiation storage.

  17. Removal of carbon-14 from irradiated graphite

    NASA Astrophysics Data System (ADS)

    Dunzik-Gougar, Mary Lou; Smith, Tara E.

    2014-08-01

    Approximately 250,000 tonnes of irradiated graphite waste exists worldwide and that quantity is expected to increase with decommissioning of Generation II reactors and deployment of Generation IV gas-cooled, graphite moderated reactors. This situation indicates the need for a graphite waste management strategy. On of the isotopes of great concern for long-term disposal of irradiated graphite is carbon-14 (14C), with a half-life of 5730 years. Study of irradiated graphite from some nuclear reactors indicates 14C is concentrated on the outer 5 mm of the graphite structure. The aim of the research presented here is to develop a practical method by which 14C can be removed. In parallel with these efforts, the same irradiated graphite material is being characterized to identify the chemical form of 14C in irradiated graphite. A nuclear-grade graphite, NBG-18, and a high-surface-area graphite foam, POCOFoam®, were exposed to liquid nitrogen (to increase the quantity of 14C precursor) and neutron-irradiated (1013 neutrons/cm2/s). During post-irradiation thermal treatment, graphite samples were heated in the presence of an inert carrier gas (with or without the addition of an oxidant gas), which carries off gaseous products released during treatment. Graphite gasification occurs via interaction with adsorbed oxygen complexes. Experiments in argon only were performed at 900 °C and 1400 °C to evaluate the selective removal of 14C. Thermal treatment also was performed with the addition of 3 and 5 vol% oxygen at temperatures 700 °C and 1400 °C. Thermal treatment experiments were evaluated for the effective selective removal of 14C. Lower temperatures and oxygen levels correlated to more efficient 14C removal.

  18. Quality of gamma ray-irradiated iceberg lettuce and treatments to minimize irradiation-induced disorders

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irradiation of Iceberg lettuce was recently approved by the FDA to enhance microbial safety and to extend shelf-life at doses up to 4 kGy. However, the radiation tolerance of whole head lettuce is unclear. The present study was conducted to investigate the effects of irradiation on the quality of he...

  19. Embrittlernent of irradiated F82H in the absence of irradiation hardening

    SciTech Connect

    Klueh, Ronald L; Shiba, Kiyoyuki; Sokolov, Mikhail A

    2009-01-01

    Neutron irradiation of 7-12% Cr ferritic/martensitic steels below 425-450 C produces microstructural defects and precipitation that cause an increase in yield stress. This irradiation hardening causes embrittlement, which is observed in a Charpy impact or fracture toughness test as an increase in the ductile-brittle transition temperature. Based on observations that show little change in strength in steels irradiated above 425-450 C, the general conclusion has been that no embrittlement occurs above these temperatures. In a recent study of F82H steel, significant embrittlement was observed after irradiation at 500 C. This embrittlement is apparently due to irradiation-accelerated Laves-phase precipitation. Observations of the embrittlement in the absence of hardening has been examined and analyzed with thermal-aging studies and computational thermodynamics calculations to illuminate and understand the effect.

  20. COBALT-60 Gamma Irradiation of Shrimp.

    NASA Astrophysics Data System (ADS)

    Sullivan, Nancy L. B.

    Meta- and ortho-tyrosine were measured using high performance liquid chromatography (HPLC) in conjunction with electrochemical detection in shrimp irradiated using cobalt-60 gamma radiation in the absorbed dose range 0.8 to 6.0 kGy, in nonirradiated shrimp, and in bovine serum albumin (BSA) irradiated in dilute aqueous solution at 25.0 kGy. Ortho-tyrosine was measured in nonirradiated BSA. Para-, meta-, and ortho-tyrosine were measured using HPLC in conjunction with uv-absorption detection in dilute aqueous solutions of phenylalanine irradiated in the absorbed dose range 16.0 to 195.0 kGy. The measured yields of tyrosine isomers were approximately linear as a function of absorbed dose in shrimp, and in irradiated solutions of phenylalanine up to 37.0 kGy. The occurrence of meta- and ortho-tyrosine, which had formerly been considered unique radiolytic products, has not previously been reported in nonirradiated shrimp or BSA. The conventional hydrolyzation and analytical techniques used in the present study to measure meta- and ortho-tyrosine may provide the basis for a method to detect and determine the dose used in food irradiation.

  1. Ion irradiation effects on metallic nanocrystals

    NASA Astrophysics Data System (ADS)

    Kluth, P.; Johannessen, B.; Giulian, R.; Schnohr, C. S.; Foran, G. J.; Cookson, D. J.; Byrne, A. P.; Ridgway, M. C.

    We have investigated structural and morphological properties of metallic nanocrystals (NCs) exposed to ion irradiation. NCs were characterized by transmission electron microscopy in combination with advanced synchrotron-based analytical techniques, in particular X-ray absorption spectroscopy and small-angle X-ray scattering. A number of different effects were observed depending on the irradiation conditions. At energies where nuclear stopping is predominant, structural disorder/amorphization followed by inverse Ostwald ripening/dissolution due to ion beam mixing was observed for Au and Cu NCs embedded in SiO2. The ion-irradiation-induced crystalline to amorphous transition in the NCs, which cannot be achieved in the corresponding bulk metals, was attributed to their initially higher structural energy as compared to bulk material and possibly preferential nucleation of the amorphous phase at the NC/SiO2 interface. At very high irradiation energies (swift heavy ion irradiation), where the energy loss is nearly entirely due to electronic stopping, a size-dependent shape transformation of the NCs from spheres to rod like shapes was apparent in Au NCs. Our preliminary results are in good agreement with considerations on melting of the NCs in the ion track as one mechanism involved in the shape transformation.

  2. Carotid artery disease following external cervical irradiation

    SciTech Connect

    Elerding, S.C.; Fernandez, R.N.; Grotta, J.C.; Lindberg, R.D.; Causay, L.C.; McMurtrey, M.J.

    1981-01-01

    A retrospective study of 910 patients surviving at least five years after cervical irradiation for Hodgkin's disease, non-Hodgkin's lymphoma, or primary head an neck neoplasms showed the incidence of stroke following cervical irradiation was 63 of 910 patients (6.3%) during a mean period of observation of nine years. This represents a trend toward an increased risk for this population observed over the same period of time (p . 0.39). A prospective study of 118 similar patients currently living five years after cervical radiotherapy was performed to determine the incidence of carotid artery disease occurring as a consequence of neck irradiation. Abnormal carotid phonangiograms (CPA) were found in 25% of the patients and abnormal oculoplethysmographs (OPG) were found in 17%. These studies represent significant carotid lesions that are not expected in such a population. It is concluded that the carotid stenoses demonstrated are most likely a consequence of prior irradiation. Patients that are five-year survivors of cervical irradiation should have noninvasive vascular laboratory studies performed as part of their routine follow-up examinations in order to detect these carotid lesions while they are occult.

  3. Neoplasms in young dogs after perinatal irradiation

    SciTech Connect

    Benjamin, S.A.; Lee, A.C.; Angleton, G.M.; Saunders, W.J.; Miller, G.K.; Williams, J.S.; Brewster, R.D.; Long, R.I.

    1986-08-01

    For a study of the life-time effects of irradiation during development, 1,680 beagles were given single, whole-body exposures to /sup 60/Co gamma-radiation at one of three prenatal (preimplantation, embryonic, and fetal) or at one of three postnatal (neonatal, juvenile, and young adult) ages. Mean doses were 0, 0.16, or 0.83 Gy. For comparison with data on childhood cancer after prenatal irradiation, examination was made of tumors occurring in young dogs in this life-span experiment. Up to 4 years of age, 18 dogs had neoplasms diagnosed, 2 of these being in controls. Four dogs that were irradiated in the perinatal (late fetal or neonatal) period died of cancers prior to 2 years of age. This risk was of significant increase compared to the risks for other experimental groups and for the canine population in general. Overall, 71% (5 of 7) of all cancers and 56% (10 of 18) of all benign and malignant neoplasms seen in the first 4 years of life occurred in 29% (480 of 1680) of the dogs irradiated in the perinatal period. These data suggest an increased risk for neoplasia after perinatal irradiation in dogs.

  4. Irradiation creep of advanced silicon carbide fibers

    NASA Astrophysics Data System (ADS)

    Scholz, R.; Youngblood, G. E.

    2000-12-01

    The bend stress relaxation (BSR) method was applied to study irradiation enhanced creep (IEC) of small diameter silicon carbide (SiC) fibers after 10 MeV proton irradiation. A first series of tests was conducted on Sylramic™ fibers irradiated at 600°C with average bending stresses of 400 and 667 MPa and for irradiation doses smaller than 0.04 dpa. The BSR results are compared to previously obtained torsional creep test results for the Textron SCS-6™ type SiC fibers by calculating the tensile equivalents for both testing methods. For the Sylramic fibers, the creep constant κ=4.7×10-6 Mpa-1 dpa-1, was a factor of 6 smaller than the κ-value determined for SCS-6 fibers at 600°C. In contrast, for T<900°C the κ-value determined by R.J. Price [Nucl. Technol. 35 (1977) 320] for high purity monolithic β-Si after 7.7 dpa neutron irradiation was only 0.4×10-6 MPa-1 dpa-1.

  5. Infrared Irradiation: Toward Green Chemistry, a Review.

    PubMed

    Escobedo, René; Miranda, René; Martínez, Joel

    2016-01-01

    This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included. PMID:27023535

  6. Effect of neutron irradiation on vanadium alloys

    SciTech Connect

    Braski, D.N.

    1986-01-01

    Neutron-irradiated vanadium alloys were evaluated for their susceptibility to irradiation hardening, helium embrittlement, swelling, and residual radioactivity, and the results were compared with those for the austenitic and ferritic stainless steels. The VANSTAR-7 and V-15Cr-5Ti alloys showed the greatest hardening between 400 and 600/sup 0/C while V-3Ti-1Si and V-20Ti had lower values that were comparable to those of ferritic steels. The V-15Cr-5Ti and VANSTAR-7 alloys were susceptible to helium embrittlement caused by the combination of weakened grain boundaries and irradiation-hardened grain matrices. Specimen fractures were entirely intergranular in the most severe instances of embrittlement. The V-3Ti-1Si and V-20Ti alloys were more resistant to helium embrittlement. Except for VANSTAR-7 irradiated to 40 dpa at 520/sup 0/C, all of the vanadium alloys exhibited low swelling that was similar to the ferritic steels. Swelling was greater in specimens that were preimplanted with helium using the tritium trick. The vanadium alloys clearly exhibit lower residual radioactivity after irradiation than the ferrous alloys.

  7. Sludge irradiation process made safe with lead

    SciTech Connect

    Not Available

    1983-03-01

    A process for disinfecting sewage sludge by irradiation is being promoted by the Department of Energy (DOE) as an efficient means of complying with Environmental Protection Agency (EPA) regulations requiring treatment of the waste material before it is recycled as a soil conditioner. The technique employs a heavy lead shutter and a generous helping of sheet lead to provide the necessary radiation shielding. For the past three years, DOE and EPA have been sponsoring a Municipal Sludge Irradiation Technology Transfer Program at Sandia National Laboratories in Albuquerque, N.M. Sandia has been operating an eight-ton-per-day pilot plant which routinely irradiates air-dried sludge for agricultural and biological studies at New Mexico State University. The objective of the program is to explore the economic and scientific aspects of irradiating sludge so it can be used as a soil additive, crop fertilizer or animal feed supplement. About 5 million tons of sludge are generated yearly in the United States. Because of the pathogenic organisms and fungi present in untreated sludge, there are health hazards associated with the recycling of sewage solids. Sandia has been investigating the types of bacteria, viruses, parasites and fungi found in sludge and the effect irradiation has on them.

  8. Measurement of Diameter Changes during Irradiation Testing

    SciTech Connect

    Davis, K. L.; Knudson, D. L.; Crepeau, J. C.; Solstad, S.

    2015-03-01

    New materials are being considered for fuel, cladding, and structures in advanced and existing nuclear reactors. Such materials can experience significant dimensional and physical changes during irradiation. Currently in the US, such changes are measured by repeatedly irradiating a specimen for a specified period of time and then removing it from the reactor for evaluation. The time and labor to remove, examine, and return irradiated samples for each measurement makes this approach very expensive. In addition, such techniques provide limited data and handling may disturb the phenomena of interest. In-pile detection of changes in geometry is sorely needed to understand real-time behavior during irradiation testing of fuels and materials in high flux US Material and Test Reactors (MTRs). This paper presents development results of an advanced Linear Variable Differential Transformer-based test rig capable of detecting real-time changes in diameter of fuel rods or material samples during irradiation in US MTRs. This test rig is being developed at the Idaho National Laboratory and will provide experimenters with a unique capability to measure diameter changes associated with fuel and cladding swelling, pellet-clad interaction, and crud buildup.

  9. Effects of irradiation on platelet function

    SciTech Connect

    Rock, G.; Adams, G.A.; Labow, R.S.

    1988-09-01

    Current medical practice involves the irradiation of blood components, including platelet concentrates, before their administration to patients with severe immunosuppression. The authors studied the effect of irradiation on in vitro platelet function and the leaching of plasticizers from the bag, both immediately and after 5 days of storage. The platelet count, white cell count, pH, glucose, lactate, platelet aggregation and release reaction, and serotonin uptake were not altered by the irradiation of random-donor or apheresis units with 2000 rads carried out at 0 and 24 hours and 5 days after collection. The leaching of di(2-ethylhexyl)phthalate from the plastic bags followed by the conversion to mono(2-ethylhexyl)phthalate was not increased by irradiation. Therefore, it is possible to irradiate platelet concentrates on the day of collection and subsequently store them for at least 5 days while maintaining in vitro function. This procedure could have considerable benefit for blood banks involved in the provision of many platelet products.

  10. Dielectric relaxation of gamma irradiated muscovite mica

    SciTech Connect

    Kaur, Navjeet; Singh, Mohan; Singh, Lakhwant; Awasthi, A.M.; Lochab, S.P.

    2015-03-15

    Highlights: • The present article reports the effect of gamma irradiation on the dielectric relaxation characteristics of muscovite mica. • Dielectric and electrical relaxations have been analyzed in the framework of dielectric permittivity, electric modulus and Cole–Cole formalisms. • The frequency dependent electrical conductivity has been rationalized using Johnsher’s universal power law. • The experimentally measured electric modulus and conductivity data have been fitted using Havriliak–Negami dielectric relaxation function. - Abstract: In the present research, the dielectric relaxation of gamma irradiated muscovite mica was studied in the frequency range of 0.1 Hz–10 MHz and temperature range of 653–853 K, using the dielectric permittivity, electric modulus and conductivity formalisms. The dielectric constants (ϵ′ and ϵ′′) are found to be high for gamma irradiated muscovite mica as compared to the pristine sample. The frequency dependence of the imaginary part of complex electric modulus (M′′) and dc conductivity data conforms Arrhenius law with single value of activation energy for pristine sample and two values of activation energy for gamma irradiated mica sample. The experimentally assessed electric modulus and conductivity information have been interpreted by the Havriliak–Negami dielectric relaxation explanation. Using the Cole–Cole framework, an analysis of real and imaginary characters of the electric modulus for pristine and gamma irradiated sample was executed which reflects the non-Debye relaxation mechanism.

  11. Infrared Irradiation: Toward Green Chemistry, a Review

    PubMed Central

    Escobedo, René; Miranda, René; Martínez, Joel

    2016-01-01

    This review provides a comprehensive overview of where infrared irradiation has been employed, mainly as regards activating green mode for natural products extractions, as well as to favor a reaction, highlighting its actual importance. It is also underlined that infrared irradiation heating has been around for a long time; however, only in the last eighteen years have many of its advantages been applied to satisfy a wide range of chemical processes, natural products extractions, and for the promotion of many kinds of reactions. In addition, it is brought to light that near infrared irradiation is more efficient than middle and far infrared irradiations, being easily controllable and with the quality of a fast responding heat source. Thus, the main objective of this review is to offer infrared irradiation as an alternative clean energy source to activate reactions, in addition to favor the selective extraction of natural products, all of which is within the Green Chemistry protocol. Some recent results from our laboratory are also included. PMID:27023535

  12. Cobalt-60 gamma irradiation of shrimp

    SciTech Connect

    Sullivan, N.L.B.

    1993-01-01

    Meta- and ortho-tyrosine were measured using high performance liquid chromatography (HPLC) in conjunction with electrochemical detection in shrimp irradiated using cobalt-60 gamma radiation in the absorbed dose range 0.8 to 6.0 kGy, in nonirradiated shrimp, and in bovine serum albumin (BSA) irradiated in dilute aqueous solution at 25.0 kGy. Ortho-tyrosine was measured in nonirradiated BSA. Para-, meta-, and ortho-tyrosine was measured using HPLC in conjunction with uv-absorption detection in dilute aqueous solutions of phenylalanine irradiated in the absorbed dose range 16.0 to 195.0 kGy. The measured yields of tyrosine isomers were approximately linear as a function of absorbed dose in shrimp, and in irradiated solutions of phenylalanine up to 37.0 kGy. The occurrence of meta- and ortho-tyrosine, which had formerly been considered unique radiolytic products, has not previously been reported in nonirradiated shrimp or BSA. The conventional hydrolyzation and analytical techniques used in the present study to measure meta- and ortho-tyrosine may provide the basis for a method to detect and determine the dose used in food irradiation.

  13. ESR spectroscopic properties of irradiated gum Arabic.

    PubMed

    Leonor, S J; Gómez, J A; Kinoshita, A; Calandreli, I; Tfouni, E; Baffa, O

    2013-12-01

    Electron spin resonance (ESR) spectra of irradiated gum Arabic with doses between 0.5 and 5 kGy were studied. A linear relationship between the absorbed dose and the intensities of the ESR spectra was observed. ESR spectra of irradiated gum Arabic showed a decay of relative concentrations of free radicals originated by radiation and the production of at least two species of free radicals with half-times: 3.3 and 125.4 h. The results of spectral simulations for these radical groups were giso=2.0046; A=1.2 mT and gx=gy=2.0062, gz=2.0025. Hydration and dehydration of irradiated gum Arabic returns the ESR spectrum to its initial state before irradiation. The results show that ESR can be used as simple and reliable method to detect irradiated gum Arabic up to 60 days after initial radiation with doses on the order of 5 kGy. PMID:23870902

  14. Ion irradiation effects on metallic nanocrystals

    SciTech Connect

    Kluth, P.; Johannessen, B.; Giulian, R.; Schnohr, C.S.; Foran, G.J.; Cookson, D.J.; Byrne, A.P.; Ridgway, M.C.

    2008-04-02

    We have investigated structural and morphological properties of metallic nanocrystals (NCs) exposed to ion irradiation. NCs were characterized by transmission electron microscopy in combination with advanced synchrotron-based analytical techniques, in particular X-ray absorption spectroscopy and small-angle X-ray scattering. A number of different effects were observed depending on the irradiation conditions. At energies where nuclear stopping is predominant, structural disorder/amorphization followed by inverse Ostwald ripening/dissolution due to ion beam mixing was observed for Au and Cu NCs embedded in SiO{sub 2}. The ion-irradiation-induced crystalline to amorphous transition in the NCs, which cannot be achieved in the corresponding bulk metals, was attributed to their initially higher structural energy as compared to bulk material and possibly preferential nucleation of the amorphous phase at the NC/SiO{sub 2} interface. At very high irradiation energies (swift heavy ion irradiation), where the energy loss is nearly entirely due to electronic stopping, a size-dependent shape transformation of the NCs from spheres to rod like shapes was apparent in Au NCs. Our preliminary results are in good agreement with considerations on melting of the NCs in the ion track as one mechanism involved in the shape transformation.

  15. Disinfestation of different cereal products by irradiation

    NASA Astrophysics Data System (ADS)

    Kovács, E.; Kiss, I.; Boros, A.; Horváth, Ny.; Tóth, J.; Gyulai, P.; Szalma, Á.

    The sensitivity of overlineTribolium confusum - small flour beetle - to radiation was studied in a dose range of 0-0.8 kGy. We found that the insect egg was the most sensitive to radiation, then larvae and pupae followed it. 0.2 kGy dose of irradiation kills these forms or their further development is inhibited. Imagoes do not immediately die after 0.8 kGy dose of irradiation; the young imagoes are more sensitive to radiation than the aged ones. 0.4 kGy average dose of irradiation is a suitable protection against overlineTribolium confusum. Disinfestation experiments were performed with wheat-germ and wheat-bran and parallelly the most important ingredients of the two products were analysed. The vitamin E content and the rate of lipid-oxidation of wheat germ were determined. The vitamin E content decreased after radiation treatment, however, during storage of at least 6 months, it remained at a level specified by food quality standards (higher than 10 mg%). Carbohydrate content of wheat-bran (water soluble carbohydrate content, crude-fibre and dietary fibre content) did not change at all. Storability of radiation disinfested wheat-germ was 8 months, wheat-bran 3-4 months. On the base of the results 2-2 tons of wheat-germ and wheat-bran were irradiated and trial marked in 1985. In 1986 the irradiation of 10 tons of wheat-germ is planned.

  16. A New Look at Solar Irradiance Variation

    NASA Astrophysics Data System (ADS)

    Foukal, Peter

    2012-08-01

    We compare total solar irradiance (TSI) and ultraviolet ( F uv) irradiance variation reconstructed using Ca K facular areas since 1915, with previous values based on less direct proxies. Our annual means for 1925 - 1945 reach values 30 - 50 % higher than those presently used in IPCC climate studies. A high facula/sunspot area ratio in spot cycles 16 and 17 seems to be responsible. New evidence from solar photometry increases the likelihood of greater seventeenth century solar dimming than expected from the disappearance of magnetic active regions alone. But the large additional brightening in the early twentieth century claimed from some recent models requires complete disappearance of the magnetic network. The network is clearly visible in Ca K spectroheliograms obtained since the 1890s, so these models cannot be correct. Changes in photospheric effective temperature invoked in other models would be powerfully damped by the thermal inertia of the convection zone. Thus, there is presently no support for twentieth century irradiance variation besides that arising from active regions. The mid-twentieth century irradiance peak arising from these active regions extends 20 years beyond the early 1940s peak in global temperature. This failure of correlation, together with the low amplitude of TSI variation and the relatively weak effect of Fuv driving on tropospheric temperature, limits the role of solar irradiance variation in twentieth century global warming.

  17. Mutation induced with ion beam irradiation in rose

    NASA Astrophysics Data System (ADS)

    Yamaguchi, H.; Nagatomi, S.; Morishita, T.; Degi, K.; Tanaka, A.; Shikazono, N.; Hase, Y.

    2003-05-01

    The effects of mutation induction by ion beam irradiation on axillary buds in rose were investigated. Axillary buds were irradiated with carbon and helium ion beams, and the solid mutants emerged after irradiation by repeated cutting back. In helium ion irradiation, mutations were observed in plants derived from 9 buds among 56 irradiated buds in 'Orange Rosamini' and in plants derived from 10 buds among 61 irradiated buds in 'Red Minimo'. In carbon ion, mutations were observed in plants derived from 12 buds among 88 irradiated buds in 'Orange Rosamini'. Mutations were induced not only in higher doses but also in lower doses, with which physiological effect by irradiation was hardly observed. Irradiation with both ion beams induced mutants in the number of petals, in flower size, in flower shape and in flower color in each cultivar.

  18. The effect of gamma irradiation on injectable human amnion collagen

    SciTech Connect

    Liu, B.C.; Harrell, R.; Davis, R.H.; Dresden, M.H.; Spira, M. )

    1989-08-01

    The effect of gamma irradiation on the physicochemical properties of injectable human amnion collagen was investigated. Pepsin-extracted human amnion collagen was purified, reconstituted, and irradiated with varying doses of gamma irradiation (0.25 Mrads to 2.5 Mrads). Gamma irradiation had a significant impact on the physical characteristics of the collagen. The neutral solubility of collagen in PBS at 45{degrees}C was decreased from 100% for the nonirradiated control sample to 16% for the 2.5 Mrads irradiated sample. SDS polyacrylamide gel electrophoresis also demonstrated the dose-dependent effect of gamma irradiation on collagen cross-links. Electron microscopic observation revealed that even at low irradiation dose (0.25 Mrads), collagen fibril diameter increased. The average diameter was 50 nm for nonirradiated control fibrils, while 4.4% of the irradiated collagen fibrils had a diameter greater than 100 nm. Irradiated collagen showed little evidence of damage. Well-preserved cross-striations were found in collagen fibrils at all doses of irradiation. Native amnion collagen irradiated with gamma rays demonstrated a slight increase in resistance to collagenase degradation compared with nonirradiated native collagen samples. Increased resistance to collagenase did not correlate with increasing irradiation dose. After 30 min of incubation at 37{degrees}C, both irradiated and nonirradiated collagen was completely digested by collagenase. However, gamma-irradiated collagen did become more sensitive to hydrolysis by trypsin. The higher the irradiation doses used, the greater sensitivity to trypsin was observed. At 0.25 Mrads irradiation only a slight increase was found. No marked differences in amino acid composition were noted among the high dose irradiated, low dose irradiated and control amnion collagen.

  19. Growth-irradiance relationships in phytoplankton

    SciTech Connect

    Falkowski, P.G.; Dubinsky, Z.; Wyman, K.

    1985-03-01

    The steady state growth rates of three species of marine phytoplankton, Thalassiosira weisflogii, Isochrysis galbana, and Prorocentrum micans, were followed in turbidostat culture. At each growth irradiance, photosynthesis and respiration were measured by following changes in oxygen. Together with measurements of optical absorption cross sections, cellular chlorophyll, carbon and nitrogen, and excretion rates as well as knowledge of the quantum flux, the quantum requirement for growth and photosynthesis were calculated. Our results suggest that variations in growth rate caused by changes in irradiance may be related to changes in respiration rates relative to growth as well as changes in optical absorption cross sections for a given species. Interspecific differences in growth rate at a given irradiance are not related to changes in respiration however, but are primarily attributable to differences in optical absorption cross sections normalized to chlorophyll and differences in chlorophyll:carbon ratios.

  20. Irradiation creep of vanadium-base alloys

    SciTech Connect

    Tsai, H.; Billone, M.C.; Strain, R.V.; Smith, D.L.; Matsui, H.

    1998-03-01

    A study of irradiation creep in vanadium-base alloys is underway with experiments in the Advanced Test Reactor (ATR) and the High Flux Isotope Reactor (HFIR) in the United States. Test specimens are thin-wall sealed tubes with internal pressure loading. The results from the initial ATR irradiation at low temperature (200--300 C) to a neutron damage level of 4.7 dpa show creep rates ranging from {approx}0 to 1.2 {times} 10{sup {minus}5}/dpa/MPa for a 500-kg heat of V-4Cr-4Ti alloy. These rates were generally lower than reported from a previous experiment in BR-10. Because both the attained neutron damage levels and the creep strains were low in the present study, however, these creep rates should be regarded as only preliminary. Substantially more testing is required before a data base on irradiation creep of vanadium alloys can be developed and used with confidence.

  1. Horizontal modular dry irradiated fuel storage system

    DOEpatents

    Fischer, Larry E.; McInnes, Ian D.; Massey, John V.

    1988-01-01

    A horizontal, modular, dry, irradiated fuel storage system (10) includes a thin-walled canister (12) for containing irradiated fuel assemblies (20), which canister (12) can be positioned in a transfer cask (14) and transported in a horizontal manner from a fuel storage pool (18), to an intermediate-term storage facility. The storage system (10) includes a plurality of dry storage modules (26) which accept the canister (12) from the transfer cask (14) and provide for appropriate shielding about the canister (12). Each module (26) also provides for air cooling of the canister (12) to remove the decay heat of the irradiated fuel assemblies (20). The modules (26) can be interlocked so that each module (26) gains additional shielding from the next adjacent module (26). Hydraulic rams (30) are provided for inserting and removing the canisters (12) from the modules (26).

  2. Status of food irradiation in the world

    NASA Astrophysics Data System (ADS)

    Kume, Tamikazu; Furuta, Masakazu; Todoriki, Setsuko; Uenoyama, Naoki; Kobayashi, Yasuhiko

    2009-03-01

    The status of food irradiation in the world in 2005 was investigated using published data, a questionnaire survey and direct visits. The results showed that the quantity of irradiated foods in the world in 2005 was 405,000 ton and comprised 1,86,000 ton (46%) for disinfection of spices and dry vegetables, 82,000 ton (20%) for disinfestation of grains and fruits, 32,000 ton (8%) for disinfection of meat and fish, 88,000 ton (22%) for sprout inhibition of garlic and potato, and 17,000 ton (4%) of other food items that included health foods, mushroom, honey, etc. Commercial food irradiation is increasing significantly in Asia, but decreasing in EU.

  3. Enucleation versus plaque irradiation for choroidal melanoma

    SciTech Connect

    Straatsma, B.R.; Fine, S.L.; Earle, J.D.; Hawkins, B.S.; Diener-West, M.; McLaughlin, J.A.

    1988-07-01

    The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.

  4. Irradiated homologous costal cartilage for augmentation rhinoplasty

    SciTech Connect

    Lefkovits, G. )

    1990-10-01

    Although the ideal reconstructive material for augmentation rhinoplasty continues to challenge plastic surgeons, there exists no report in the literature that confines the use of irradiated homologous costal cartilage, first reported by Dingman and Grabb in 1961, to dorsal nasal augmentation. The purpose of this paper is to present a retrospective analysis of the author's experience using irradiated homologous costal cartilage in augmentation rhinoplasty. Twenty-seven dorsal nasal augmentations were performed in 24 patients between 16 and 49 years of age with a follow-up ranging from 1 to 27 months. Good-to-excellent results were achieved in 83.3% (20 of 24). Poor results requiring revision were found in 16.7% (4 of 24). Complication rates included 7.4% infection (2 of 27) and 14.8% warping (4 of 27). The resorption rate was zero. These results compare favorably with other forms of nasal augmentation. Advantages and disadvantages of irradiated homologous costal cartilage are discussed.

  5. Dosimetry procedures for an industrial irradiation plant

    NASA Astrophysics Data System (ADS)

    Grahn, Ch.

    Accurate and reliable dosimetry procedures constitute a very important part of process control and quality assurance at a radiation processing plant. γ-Dose measurements were made on the GBS 84 irradiator for food and other products on pallets or in containers. Chemical dosimeters wre exposed in the facility under conditions of the typical plant operation. The choice of the dosimeter systems employed was based on the experience in chemical dosimetry gained over several years. Dose uniformity information was obtained in air, spices, bulbs, feeds, cosmetics, plastics and surgical goods. Most products currently irradiated require dose uniformity which can be efficiently provided by pallet or box irradiators like GBS 84. The radiation performance characteristics and some dosimetry procedures are discussed.

  6. Nanoimprint lithography using IR laser irradiation

    NASA Astrophysics Data System (ADS)

    Grigaliūnas, V.; Tamulevičius, S.; Muehlberger, M.; Jucius, D.; Guobienė, A.; Kopustinskas, V.; Gudonytė, A.

    2006-11-01

    A new technique called "infrared laser-assisted nanoimprint lithography" was utilised to soften the thermoplastic polymer material mR-I 8020 during nanoimprint lithography. A laser setup and a sample holder with pressure and temperature control were designed for the imprint experiments. The polymer was spin coated onto crystalline Si <1 1 1> substrates. A prepatterned Si <1 1 1> substrate, which is transparent for the CO 2 laser irradiation, was used as an imprint stamp as well. It was shown, that the thermoplastic resist mR-I 8020 could be successfully imprinted using the infrared CW CO 2 laser irradiation ( λ = 10.6 μm). The etching rate of the CO 2 laser beam irradiated mR-I 8020 resist film under O 2 RF (13.56 MHz) plasma treatment and during O 2 reactive ion beam etching was investigated as well.

  7. The solar irradiance: observations and modelling

    NASA Astrophysics Data System (ADS)

    Cessateur, Gaël; Schmutz, Werner; Shapiro, Alexander

    2015-04-01

    The knowledge of the solar spectral irradiance (SSI) and its variability is an essential parameter for space weather and space climate studies. Many observations of the SSI have been performed in a recent past, but the level of confidence is rather low when considering long time scales, since space instruments are often suffering from degradation problems. Many SSI models have been also developed, and some of them are excellent inputs for many space climate models. We will then review the different data sets available of the SSI for the short term time-scales as well as for the long term, including both observations and models. We will also emphasize about our new irradiance model, COSIR for Code of Solar Irradiance Reconstruction, which is successful at reproducing the solar rotational modulation as seen in the PREMOS, Virgo and SORCE data.

  8. Laboratory for Characterization of Irradiated Graphite

    SciTech Connect

    Karen A. Moore

    2010-03-01

    The newly completed Idaho National Laboratory (INL) Carbon Characterization Laboratory (CCL) is located in Labs C19 and C20 of the Idaho National Laboratory Research Center (IRC). The CCL was established under the Next Generation Nuclear Plant (NGNP) Project to support graphite and ceramic composite research and development activities. The research is in support of the Advanced Graphite Creep (AGC) experiment — a major material irradiation experiment within the NGNP Graphite program. The CCL is designed to characterize and test low activated irradiated materials such as high purity graphite, carbon-carbon composites, and silicon-carbide composite materials. The laboratory is fully capable of characterizing material properties for both irradiated and nonirradiated materials.

  9. Health risk assessment of irradiated topaz

    SciTech Connect

    Nelson, J.W.; Baum, J.W. )

    1993-01-01

    Irradiated topaz gemstones are currently processed for color improvement by subjecting clear stones to neutron or high-energy electron irradiations, which leads to activation of trace elements in the stones. Assessment of the risk to consumers required the identification and quantification of the resultant radionuclides and the attendant exposure. Representative stones from Brazil, India, Nigeria, Sri Lanka were irradiated and analyzed for gamma ray and beta particle emissions, using sodium iodide and germanium spectrometers; and Geiger-Muller, plastic and liquid scintillation, autoradiography, and thermoluminescent-dosimetry measurement techniques. Based on these studies and other information derived from published literature, dose and related risk estimates were made for typical user conditions. New criteria and methods for routine assays for acceptable release, based on gross beta and gross photon emissions from the stones, were also developed.

  10. Irradiation chemistry in the outer solar system

    NASA Astrophysics Data System (ADS)

    Brown, Michael E.

    2014-11-01

    The dark, reddish tinged surfaces of icy bodies in the outer solar are usually attributed to the long term irradiation of simple hydrocarbons such as methane leading to the loss of hydrogen and the production of long carbon chains. While methane is stable and detected on the most massive bodies in the Kuiper belt, evidence of active irradiation chemistry is scant except for the presence of ethane on methane-rich Makemake and possible detections of ethane on more methane-poor Pluto and Quaoar. We have obtained deep high signal-to-noise spectra of Makemake from 1.5 to 2.5 microns in an attempt to trace the radiation chemistry in the outer solar system beyond the initial ethane formation. We present the first astrophysical detections of solid ethylene, acetylene, and possibly propane -- all expected products of the continued irradiation of methane, and use these species to map the chemical pathway from methane to long-chain hydrocarbons.

  11. Electroslag remelt processing of irradiated vanadium alloys

    NASA Astrophysics Data System (ADS)

    Carmack, W. J.; Smolik, G. R.; McCarthy, K. A.

    1996-10-01

    This paper describes experimental efforts to investigate the potential of a slag remelting process for reducing radioactivity of irradiated vanadium alloys used in a fusion power production facility. The experiment determined the removal characteristics of four surrogate transmutation isotopes significant to accident safety expected in a V5Ti5Cr alloy irradiated under fusion conditions (Ca, Y, to simulate Sc, Mn, and Ar). Removal of these isotopes could decrease the accident risk of reprocessing irradiated vanadium and reusing it in fusion reactors. An electroslag remelt furnace was used in the experiment to melt and react the constituents using a calcium fluoride slag. The process achieved 90% removal of calcium and over 99% removal of yttrium. Analyses indicate that 40% of the manganese has been removed. Argon analysis of the refined ingots indicates that 99% of the argon was removed from the vanadium alloy.

  12. Acoustic emission from irradiated nuclear graphite

    NASA Astrophysics Data System (ADS)

    Burchell, T. D.; Rose, A. P. G.; McEnaney, B.

    1986-08-01

    Measurements of acoustic emission (AE) from a range of four unirradiated nuclear graphites during three-point bend tests are reported. Results are in agreement with the trends found in earlier work using different AE apparatus. The technique is applied to the testing of small beam specimens cut from irradiated Civil Advanced Gas-cooled Reactor (CAGR) graphite fuel sleeves after discharge from the reactor. The AE information is explained by considering separately the known changes in graphite microstructure that occur in the reactor due to radiolytic oxidation and fast neutron irradiation. Coarsening of the material due to radiolytic oxidation increases the total number of AE events and the proportion of events of low amplitude. Fast neutron irradiation increases the fracture stress and makes the stress-strain curve more linear. As a consequence, the number of AE events is reduced along with the proportion of events of low amplitude.

  13. Neutrophil myeloperoxidase destruction by ultraviolet irradiation

    SciTech Connect

    Hanker, J.; Giammara, B.; Strauss, G.

    1988-01-01

    The peroxidase activity of enriched leukocyte preparations on coverslips was determined cytochemically with a newly developed method. The techniques utilizes diaminobenzidine medium and cupric nitrate intensification and is suitable for analysis with light microscopy, SEM, and TEM. Blood specimens from control individuals were studied with and without in vitro UV irradiation and compared with those from psoriasis patients exposed therapeutically to various types of UV in phototherapy. All UV irradiated samples showed diminished neutrophil myeloperoxidase (MP) activity although that of the principal eosinophil peroxidase was unaffected. The SEMs supported the contention that decreased neutrophil MP activity might be related to UV induced degranulation. It is believed to be possible, eventually, to equate the observed MP degranulation effect after UV irradiation with diminished ability to fight bacterial infections.

  14. Effects of Laser Irradiation on Peripheral Nerve

    NASA Astrophysics Data System (ADS)

    Baxter, G. D.; Chow, R.; Armati, P.; Bjordal, J. M.; Laakso, L.

    2009-06-01

    A literature review was undertaken to determine the electrophysiological effects of Laser Irradiation (LI) on peripheral mammalian nerves, as a means of elucidating the potential mechanisms underlying pain relief associated with laser therapy. Relevant computerized databases and reference lists were searched, and experts consulted for further articles. A total of 38 studies, comprising 82 separate experiments were identified. In human studies, all types of LI (red and infrared, pulsed and cw) slowed nerve conduction velocity, and reduced compound action potential of irradiated nerves. In animal studies, infrared LI suppressed conduction velocity, as well as noxious stimulation evoked potential. This review thus indicates the potential of laser irradiation to inhibit activity in peripheral nerves, and highlights one potential mechanism of action for laser-mediated pain relief.

  15. Neutron irradiation effects in GaAs

    SciTech Connect

    Patel, J.U.

    1992-01-01

    Changes in electrical properties of n-GaAs as a result of irradiations with fast neutron have been studied, after epitaxial layers doped with Si at concentrations in the range 1.35 x 10[sup 15] to 1.60 x 10[sup 16] cm[sup [minus]3] were irradiated with reactor neutron fluences up to 1.31 x 10[sup 15] cm [sup [minus]2]. When the changes in carrier concentration, Hall mobility and resistivity were more than 25% of their initial values, nonlinear dependence on neutron fluence was apparent. New theory is proposed which explains the changes in electrical properties in terms of rates of trapping and release of charges. A theoretical relationship is derived for the change in carrier concentration as a function of neutron fluence and Fermi level shift was found to be consistent with the observed changes in carrier concentration. A correlation has been found between the changes in carrier concentration and mobility with neutron fluence using newly defined physically meaningful parameters in the case of two pairs of samples. The correlation has been explained in terms of the increased scattering of charge carriers from the defects created by neutrons that trap the free carriers. Mobility changes were measured at temperatures from 15 K to 305 K in n-GaAs van-der Pauw samples irradiated by fast reactor neutrons. The inverse mobility values obtain versus temperature, from the variable temperature Hall measurements, in the case of irradiated and in-irradiated samples were fitted using the relation [mu][sup [minus]1] = T[sup [minus]3/2] + B T[sup 3/2]. The inverse mobility increased as a result of neutron irradiations over the whole range of temperature, the increase being attributed to the increased scattering from neutron induced charged defects.

  16. Structural change of graphite during electron irradiation

    SciTech Connect

    Koike, J. . Dept. of Mechanical Engineering); Pedraza, D.F. )

    1992-01-01

    Highly oriented pyrolytic graphite was irradiated at room temperature with 300-keV electrons. High resolution transmission electron microscopy and electron energy loss spectroscopy were employed to study the structure of electron-irradiated graphite. Results consistently indicated absence of long-range order periodicity in the basal plane, and loose retention of the c-axis periodicity. Structure was modeled based on a mixture of sixfold and non-sixfold atom rings. Formation of non-sixfold atom rings was related to the observed buckling and discontinuity of the original graphite basal plane.

  17. Structural change of graphite during electron irradiation

    SciTech Connect

    Koike, J.; Pedraza, D.F.

    1992-12-31

    Highly oriented pyrolytic graphite was irradiated at room temperature with 300-keV electrons. High resolution transmission electron microscopy and electron energy loss spectroscopy were employed to study the structure of electron-irradiated graphite. Results consistently indicated absence of long-range order periodicity in the basal plane, and loose retention of the c-axis periodicity. Structure was modeled based on a mixture of sixfold and non-sixfold atom rings. Formation of non-sixfold atom rings was related to the observed buckling and discontinuity of the original graphite basal plane.

  18. The effects of sunspots on solar irradiance

    NASA Technical Reports Server (NTRS)

    Hudson, H. S.; Silva, S.; Woodard, M.; Willson, R. C.

    1982-01-01

    It is pointed out that the darkness of a sunspot on the visible hemisphere of the sun will reduce the solar irradiance on the earth. Approaches are discussed for obtaining a crude estimate of the irradiance deficit produced by sunspots and of the total luminosity reduction for the whole global population of sunspots. Attention is given to a photometric sunspot index, a global measure of spot flux deficit, and models for the compensating flux excess. A model is shown for extrapolating visible-hemisphere spot areas to the invisible hemisphere. As an illustration, this extrapolation is used to calculate a very simple model for the reradiation necessary to balance the flux deficit.

  19. Schistosoma mansoni: cercarial responses to irradiance changes

    SciTech Connect

    Saladin, K.S.

    1982-02-01

    Cercariae of Schistosoma mansoni alternate between active swimming and passive drifting. They began swimming in response to either an increase or decrease in irradiance experienced during the passive phase. The number of cercariae reacting to a shadow was proportional to the magnitude of the stimulus. The shadow response may be mediated by the cercaria's ciliary receptors. About half as many cercariae reacted to an irradiance increase as to an equivalent decrease. This report is the first quantitative study of photosensory stimulus-response relationships in schistosome cercariae.

  20. Effects of gamma irradiation on deteriorated paper

    NASA Astrophysics Data System (ADS)

    Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

    2016-08-01

    Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

  1. Vanadium irradiation at ATR - neutronics aspects

    SciTech Connect

    Gomes, I.C.; Smith, D.L.

    1995-04-01

    Calculations were performed to estimate damage and transmutation rates in vanadium irradiated in the ATR (Advanced Test Reactor) located in Idaho. The main focuses of the study are to evaluate the transmutation of vanadium to chromium and to explore ways to design the irradiation experiment to avoid excessive transmutation. It was found that the A-hole of ATR produces damage rate of {approximately} 0.2%/dpa of vanadium to chromium. A thermal neutron filter can be incorporated into the design to reduce the vanadium-to-chromium transmutation rate to low levels. A filter 1-2 mm thick of gadolinium or hafnium can be used.

  2. Separation of sodium-22 from irradiated targets

    DOEpatents

    Taylor, Wayne A.; Jamriska, David

    1996-01-01

    A process for selective separation of sodium-22 from an irradiated target including dissolving an irradiated target to form a first solution, contacting the first solution with hydrated antimony pentoxide to selectively separate sodium-22 from the first solution, separating the hydrated antimony pentoxide including the separated sodium-22 from the first solution, dissolving the hydrated antimony pentoxide including the separated sodium-22 in a mineral acid to form a second solution, and, separating the antimony from the sodium-22 in the second solution.

  3. Neutron Spectrum Measurements from Irradiations at NCERC

    SciTech Connect

    Jackman, Kevin Richard; Mosby, Michelle A.; Bredeweg, Todd Allen; Hutchens, Gregory Joe; White, Morgan Curtis

    2015-04-15

    Several irradiations have been conducted on assemblies (COMET/ZEUS and Flattop) at the National Criticality Experiments Research Center (NCERC) located at the Nevada National Security Site (NNSS). Configurations of the assemblies and irradiated materials changed between experiments. Different metallic foils were analyzed using the radioactivation method by gamma-ray spectrometry to understand/characterize the neutron spectra. Results of MCNP calculations are shown. It was concluded that MCNP simulated spectra agree with experimental measurements, with the caveats that some data are limited by statistics at low-energies and some activation foils have low activities.

  4. Evaluation of CERES surface irradiance products

    NASA Astrophysics Data System (ADS)

    Kato, S.; Loeb, N. G.; Rose, F. G.; Rutan, D. A.; Doelling, D.; Radkevich, A.; Ham, S. H.

    2014-12-01

    Understanding the surface radiation budget is important for several reasons. At the global and large temporal scales, it should balance with the sum of surface latent and sensible heat fluxes and ocean heating. At regional scales, it is an indispensable boundary condition for ocean or snow models or any other models that need energy input to the surface. NASA's Clouds and the Earth's Radiant Energy System (CERES) project provides surface irradiance data products for a range of temporal and spatial scales computed using a radiative transfer model initialized using satellite-derived cloud and aerosol properties. Other inputs to the radiative transfer model include temperature and humidity profiles from NASA Global Modeling and Assimilation Office's (GMAO) reanalysis. The CERES team uses more than 80 surface observation sites located over land and ocean to evaluate computed irradiances. When computed monthly 1° by 1° gridded mean downward irradiances are compared with 10 years of observed irradiances, the bias averaged over all land and ocean sites are, respectively, -1.7 Wm-2 and 4.7 Wm-2 for shortwave and -1.0 Wm-2 and -2.0 Wm-2 for longwave. The shortwave agreement is significantly better than other satellite-based surface irradiance products. One of reasons for the better agreement is careful treatment of diurnal cycle of clouds by merging 3-hourly geostationary satellite-derived cloud properties. In addition, computed surface irradiance variability shows a remarkable agreement with observed variability. However, these data sets have their shortcomings. The uncertainty in nighttime surface longwave irradiance over polar regions is larger than that of other regions primarily due to the difficulty of cloud detection and large uncertainties in skin temperature and near-surface temperature and humidity. The large uncertainty in polar region surface irradiances hampers, for example, investigation of surface radiation budget changes in response to changes in sea ice

  5. Electron irradiation of modern solar cells

    NASA Technical Reports Server (NTRS)

    Anspaugh, B. E.; Miyahira, T. F.

    1977-01-01

    A number of modern solar cell types representing 1976 technology (as well as some older types) were irradiated with 1 MeV electrons (and a limited number with 2 MeV electrons and 10 MeV protons). After irradiation, the cells were annealed, with I-V curves measured under AMO at 30 C. The purpose was to provide data to be incorporated in the revision of the solar cell radiation handbook. Cell resistivities ranged from 2 to 20 ohm-cm, and cell thickness from 0.05 to 0.46 mm. Cell types examined were conventional, shallow junction, back surface field (BSF), textured, and textured with BSF.

  6. Consequences of Cytoplasmic Irradiation: Studies from Microbeam

    PubMed Central

    Zhou, Hongning; Hong, Mei; Chai, Yunfei; Hei, Tom K.

    2013-01-01

    The prevailing dogma for radiation biology is that genotoxic effects of ionizing radiation such as mutations and carcinogenesis are attributed mainly to direct damage to the nucleus. However, with the development of microbeam that can target precise positions inside the cells, accumulating evidences have shown that energy deposit by radiation in nuclear DNA is not required to trigger the damage, extra-nuclear or extra-cellular radiation could induce the similar biological effects as well. This review will summarize the biological responses after cytoplasm irradiated by microbeam, and the possible mechanisms involved in cytoplasmic irradiation. PMID:19346686

  7. Long-Term Solar Irradiance Variability

    NASA Technical Reports Server (NTRS)

    Pap, J. M.

    1996-01-01

    Measurements of the solar energy throughout the solar spectrum and understanding its variability provide important information about the physical processes and structural changes in the solar interior and in the solar atmosphere...The aim of this paper is to discuss the solar-cycle-related long-term changes in solar total and UV irradiances. The spaceborne irradiance observations are compared to ground-based indices of solar magnetic activity, such as the Photometric Sunspot Index, full disk magnetic flux, and the Mt. Wilson Magnetic Plage Strength Index.

  8. Interstitial irradiation of brain tumors: a review

    SciTech Connect

    Bernstein, M.; Gutin, P.H.

    1981-12-01

    As an adjuvant to surgery, radiation therapy has consistently proven to be the most successful form of treatment for primary and secondary malignant brain tumors and possibly for inoperable benign tumors. Because the risk of radiation necrosis of normal brain limits the amount of radiation that can be given by external beam therapy at conventional dose rates, interstitial radiation of brain tumors is a logical alternative treatment approach. We discuss the radiobiological advantages of low dose rate irradiation and intratumoral placement of sources that make interstitial irradiation an attractive treatment for brain tumors and review the history of clinical brachytherapy for intracranial neoplasia.

  9. Agglomeration defects on irradiated carbon nanotubes

    SciTech Connect

    Steini Moura, Cassio; Balzaretti, Naira Maria; Amaral, Livio; Gribel Lacerda, Rodrigo; Pimenta, Marcos A.

    2012-03-15

    Aligned carbon nanotubes (CNT) were irradiated in the longitudinal and perpendicular directions, with low energy carbon and helium ions in order to observe the formation of defects in the atomic structure. Analysis through Raman spectroscopy and scanning electron microscopy indicated bundle rupture and ion track formation on nanotube bundles. Aligned CNT presented a kind of defect comprising ravine formation and tube agglomeration on top of the substrate. The latter structure is possibly caused by static charge accumulation induced by the incoming ions. Fluence plays a role on the short range order. Higher fluence irradiation transforms CNT into amorphous carbon nanowires.

  10. Heavy-Section Steel Irradiation Program

    SciTech Connect

    Rosseel, T.M.

    2000-04-01

    Maintaining the integrity of the reactor pressure vessel (RPV) in a light-water-cooled nuclear power plant is crucial in preventing and controlling severe accidents that have the potential for major contamination release. Because the RPV is the only key safety-related component of the plant for which a redundant backup system does not exist, it is imperative to fully understand the degree of irradiation-induced degradation of the RPV's fracture resistance that occurs during service. For this reason, the Heavy-Section Steel Irradiation (HSSI) Program has been established.

  11. Irradiated versus fumigated spices in sausage.

    PubMed

    Bolander, C R; Toma, R B; Davis, R M; Medora, N P

    1995-11-01

    The efficacy of gamma radiation and ethylene oxide fumigation as decontaminating treatments for spices used in sausages was compared. Microbial loads of sausages containing irradiated, fumigated or non-treated spices were examined over three intervals of time. No significant differences between microbial loads of Mexican sausages containing irradiated spices (10 kGy) verses ethylene oxide-treated spices were found. Mexican sausages containing treated spices had significantly lower yeast, mould and spore counts than control sausages. After 8 weeks of storage, only the microbial loads of control sausages suggested spoilage. No discernable differences in treatment efficacy were noted with respect to yeast, mould and spore counts in Italian sausages. PMID:8574858

  12. Irradiation of meat products, chicken and use of irradiated spices for sausages

    NASA Astrophysics Data System (ADS)

    Kiss, I. F.; Beczner, J.; Zachariev, Gy.; Kovács, S.

    The shelf-life of packed minced meat has been increased at least threefold at 4°C by applying a 2 kGy dose. Results have been confirmed by detailed quatitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated samples. The optimal average dose was 4 kGy for packed-frosen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterbacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. In sensory evaluations there was no significant difference between untreated and irradiated samples. In 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices.

  13. Understanding the Irradiation Behavior of Zirconium Carbide

    SciTech Connect

    Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

    2013-10-11

    Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC-based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation

  14. Generation of overdense and high-energy electron-positron-pair plasmas by irradiation of a thin foil with two ultraintense lasers.

    PubMed

    Chang, H X; Qiao, B; Xu, Z; Xu, X R; Zhou, C T; Yan, X Q; Wu, S Z; Borghesi, M; Zepf, M; He, X T

    2015-11-01

    A scheme for enhanced quantum electrodynamics (QED) production of electron-positron-pair plasmas is proposed that uses two ultraintense lasers irradiating a thin solid foil from opposite sides. In the scheme, under a proper matching condition, in addition to the skin-depth emission of γ-ray photons and Breit-Wheeler creation of pairs on each side of the foil, a large number of high-energy electrons and photons from one side can propagate through it and interact with the laser on the other side, leading to much enhanced γ-ray emission and pair production. More importantly, the created pairs can be collected later and confined to the center by opposite laser radiation pressures when the foil becomes transparent, resulting in the formation of unprecedentedly overdense and high-energy pair plasmas. Two-dimensional QED particle-in-cell simulations show that electron-positron-pair plasmas with overcritical density 10(22) cm(-3) and a high energy of 100s of MeV are obtained with 10 PW lasers at intensities 10(23) W/cm(2), which are of key significance for laboratory astrophysics studies. PMID:26651802

  15. Solar total and spectral irradiance reconstruction over last 9000 years

    NASA Astrophysics Data System (ADS)

    Wu, Chi-Ju; Usoskin, Ilya; Krivova, Natalie; Solanki, Sami K.

    2016-07-01

    Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

  16. Modeling precipitate evolution in zirconium alloys during irradiation

    NASA Astrophysics Data System (ADS)

    Robson, J. D.

    2016-08-01

    The second phase precipitates (SPPs) in zirconium alloys are critical in controlling their performance. During service, SPPs are subject to both thermal and irradiation effects that influence volume fraction, number, and size. In this paper, a model has been developed to capture the combined effect of thermal and irradiation exposure on the Zr(Fe,Cr)2 precipitates in Zircaloy. The model includes irradiation induced precipitate destabilization integrated into a classical size class model for nucleation, growth and coarsening. The model has been applied to predict the effect of temperature and irradiation on SPP evolution. Increasing irradiation displacement rate is predicted to strongly enhance the loss of particles that arises from coarsening alone. The effect of temperature is complex due to competition between coarsening and irradiation damage. As temperature increases, coarsening is predicted to become increasingly important compared to irradiation induced dissolution and may increase resistance to irradiation induced dissolution by increasing particle size.

  17. Neutron irradiation of Am-241 effectively produces curium

    NASA Technical Reports Server (NTRS)

    Anderson, R. W.; Milstead, J.; Stewart, D. C.

    1967-01-01

    Computer study was made on the production of multicurie amounts of highly alpha-active curium 242 from americium 241 irradiation. The information available includes curium 242 yields, curium composition, irradiation data, and production techniques and safeguards.

  18. Splenic injury caused by therapeutic irradiation

    SciTech Connect

    Dailey, M.O.; Coleman, C.N.; Fajardo, L.F.

    1981-06-01

    Splenic irradiation in the course of therapy for lymphoma can result in functional deficit, sometimes as severe as that caused by splenectomy, placing the patient at risk for fatal infection. We examined 33 spleens obtained at necropsy from patients irradiated for lymphomas (mainly Hodgkin's disease) and compared them with 18 nonirradiated spleens from similar patients. One to 8 years after a mean radiation dose of 3899 rads, fractionated over 5-6 weeks, most irradiated spleens were small (average weight 75 g) and had thick, wrinkled capsules, often with focal hemorrhage. There was collapse of the parenchyma, with close apposition of trabeculae and mild to severe diffuse fibrosis of the red pulp. Lymphocyte depletion was obvious in more than 50% of the specimens. The most consistent alteration was myointimal proliferation of arteries. Significant intimal thickening was seen only in the irradiated specimens. Similar myointimal changes were found in the veins of three cases. While none of these changes is specific, their combination appears to be characteristic of delayed radiation injury to the spleen.

  19. Polymer Morphological Change Induced by Terahertz Irradiation

    PubMed Central

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-01-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10−20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules. PMID:27272984

  20. Preservation of fresh noodles by irradiation

    NASA Astrophysics Data System (ADS)

    Jianming, Cai

    1998-06-01

    At the present paper, it is studied to preserve fresh noodles by irradiation. The noodles which were irradiated by 10 kGy of 60Co-γ rays and stored at room temperature (18-24°C). The appearance of the noodles was observed, the bacteria in the noodles were examines, and the acidity of the noodles was measured during 10 days after irradiation. The results showed that the number of bacteria and the extent of acidification of the noodles were in inverse proportion to radiation dose. When the absorbed dose was less than 8 kGy, the residual bacteria in the noodles could proliferate massively in several days and acidified the noodles. The pH of these noodles decreased from 6.2 to 5.0 or less and the noodles turned into sticky during storage. When the absorbed dose reached 8-10 kGy, most of bacteria were killed and the acidity of the noodles kept about pH 6.0. The appearance of the noodles looks fresh within 10 days after irradiation. They smelled as good as fresh ones.

  1. Susceptibility of irradiated steels to hydrogen embrittlement

    NASA Technical Reports Server (NTRS)

    Rossin, A. D.

    1968-01-01

    Investigation determined whether irradiated pressure-vessel steels 4340 and 212-B are susceptible to hydrogen embrittlement and to catastrophic failure. Hydrogen-charging conditions which completely embrittled 4340 steel had negligible effect on 212-B steel in tensile and delayed-failure tests.

  2. Sucrose synthesis in gamma irradiated sweet potato

    SciTech Connect

    Ailouni, S.; Hamdy, M.K.; Toledo, R.T.

    1987-01-01

    Effect of ..cap alpha..-irradiation carbohydrate metabolism was examined to elucidate mechanism of sucrose accumulation in sweet potato (SP). Enzymes examined were: ..beta..-amylase, phosphorylase, phosphoglucomutase, phosphoglucose isomerase, sucrose phosphate synthetase and sucrose synthetase. Irradiated SP (Red Jewell) sucrose was synthesized to yield 10.7% after 4 d PI. Activities of sugar synthesizing enzymes in irradiated SP were enhanced to different degrees using 100-200 Krad and 3 d PI at 24/sup 0/C. Phosphorylase and phosphoglucomutases specific activities reached 2.4 and 1.8 folds, respectively compared to control SP. ..beta..-amylase, phosphoglucose isomerase, sucrose synthetase and sucrose phosphate synthetase were also affected to yield 1.2, 1.3, 1.3 and 1.2 folds, respectively compared to controls. It is believed that amylase hydrolyzed starch to glucose which is converted to fructose by phosphoglucose isomerase. Sucrose is then formed by sucrose phosphate synthetase and/or sucrose synthetase leading to its accumulation. The irradiated SP was used for alcohol fermentation leading to 500 gal. of 200 proof ethanol/acre (from 500-600 bushels tuber/acre).

  3. Hyperparathyroidism After Irradiation for Childhood Malignancy

    SciTech Connect

    McMullen, Todd; Bodie, Greg; Gill, Anthony; Ihre-Lundgren, Catharina; Shun, Albert; Bergin, Mary; Stevens, Graham; Delbridge, Leigh

    2009-03-15

    Purpose: To examine the occurrence of hyperparathyroidism in a cohort of patients undergoing combined parathyroid and thyroid surgery after previous head-and-neck irradiation for childhood malignancy. Methods and Materials: This is a retrospective cohort study for the years 1996 to 2007. The study group comprised patients undergoing surgery in University of Sydney Endocrine Surgical Unit who had received previous head-and-neck irradiation in childhood and who were identified as having pathologic thyroid and parathyroid characteristics. Results: A total of 53 patients were identified in whom head-and-neck irradiation for the treatment of childhood malignancy had been documented. In each of the cases, thyroid disease was the primary reason for referral for surgery. Five of these patients (10%) were found to exhibit coexisting hyperparathyroidism. The latency period for hyperparathyroidism was less than 20 years in 4 of the 5 cases. There were four conventional parathyroid adenomas and one parathyroid lipoadenoma. All patients exhibited a significant decrease in postoperative calcium levels after surgery. Conclusions: To our knowledge, this is the first study to document the significant risk of hyperparathyroidism after radiation exposure for childhood malignancy. The timeframe for development of disease is much shorter than that published for individuals who have undergone irradiation for benign diseases. High doses of therapeutic radiation at a young age make childhood survivors of malignancy at especially high risk for developing hyperparathyroidism.

  4. Monitoring pathogens from irradiated agriculture products

    NASA Astrophysics Data System (ADS)

    Butterweck, Joseph S.

    The final food and environmental safety assessment of agriculture product irradiation can only be determined by product history. Product history will be used for future research and development, regulations, commercial practices and implementation of agriculture and food irradiation on a regional basis. The commercial irradiator treats large varieties and amounts of products that are used in various environments. It, in time, will generate a large data base of product history. Field product monitoring begins when food irradiation progresses from the pilot/demonstration phase to the commercial phase. At that time, it is important that there be in place a monitoring system to collect and analyze field data. The systems managers, public health authorities and exotic disease specialists will use this information to assess the reduction of food pathogens on the populace and the environment. The common sources of monitoring data are as follows: 1) Host Monitoring a) Medical Diagnosis b) Autopsy c) Serology Surveys 2) Environmental Monitoring a) Sentinel b) Pest Surveys/Microbial Counts c) Sanitary Inspections 3) Food Industries Quality Assurance Monitoring a) End Product Inspection b) Complaints c) Continual Use of the Product

  5. Nonintrusive irradiated fuel inventory confirmation technique

    SciTech Connect

    Dowdy, E.J.; Nicholson, N.; Caldwell, J.T.

    1980-01-01

    Successful tests showing correlation between the intensity of the Cerenkov glow surrounding irradiated fuel assemblies in water-filled spent fuel storage ponds and the exposure and cooling times of assemblies have been concluded. Fieldable instruments used in subsequent tests confirmed that such measurements can be made easily and rapidly, without fuel assembly movement or the introduction of apparatus into the storage ponds.

  6. Active diaphragm rupture with laser beam irradiation

    NASA Astrophysics Data System (ADS)

    Takahashi, T.; Torikai, H.; Yang, Q. S.; Watanabe, K.; Sasoh, A.

    We performed shock tube operations with a layer of diaphragm being ruptured by laser beam irradiation. Mylar or Cellophane was examined as the diaphragm material. It has been demonstrated that shock tube can be operated with this new technique. The absorbed energy depends on the material and thickness of the diaphragm and is an important control parameter.

  7. Performance validation of an irradiance redistribution guide

    NASA Astrophysics Data System (ADS)

    Lewandowski, Allan; Bingham, Carl; Shatz, Narkis E.; Bortz, John C.

    1997-10-01

    Science Applications International Corporation has used a unique nonimaging-optical global optimization computer code, NICOS, to design an innovative secondary concentrator for the National Renewable Energy Laboratory (NREL). NICOS allows for the optimal design of such devices to achieve a variety of irradiance distributions on a desired target. The case of interest to NREL called for a uniform irradiance of concentrated sunlight over a relatively large area and at a reasonable working distance from the exit of the device. Because the irradiance at the nominal focal point of NREL's High-Flux Solar Furnace (HFSF) was reshaped from a near- Gaussian distribution to a nearly uniform one, the designs generated have been called irradiance redistribution guides (IRG). A design featuring reentrant optics was selected for fabrication and testing. This IRG has been fabricated and tested at the HFSF to compare predicted and measured performance. The IRG's performance is close to the theoretical predictions. Much of the performance difference can be explained by discrepancies between the actual HFSF performance relative to that assumed in the NICOS predictions. This IRG will be useful for applications in which uniform solar concentration at moderate flux is required. In general, the design methodology and resulting devices can provide a new way to satisfy diverse flux tailoring needs.

  8. Polymer Morphological Change Induced by Terahertz Irradiation

    NASA Astrophysics Data System (ADS)

    Hoshina, Hiromichi; Suzuki, Hal; Otani, Chiko; Nagai, Masaya; Kawase, Keigo; Irizawa, Akinori; Isoyama, Goro

    2016-06-01

    As terahertz (THz) frequencies correspond to those of the intermolecular vibrational modes in a polymer, intense THz wave irradiation affects the macromolecular polymorph, which determines the polymer properties and functions. THz photon energy is quite low compared to the covalent bond energy; therefore, conformational changes can be induced “softly,” without damaging the chemical structures. Here, we irradiate a poly(3-hydroxybutylate) (PHB) / chloroform solution during solvent casting crystallization using a THz wave generated by a free electron laser (FEL). Morphological observation shows the formation of micrometer-sized crystals in response to the THz wave irradiation. Further, a 10‑20% increase in crystallinity is observed through analysis of the infrared (IR) absorption spectra. The peak power density of the irradiating THz wave is 40 MW/cm2, which is significantly lower than the typical laser intensities used for material manipulation. We demonstrate for the first time that the THz wave effectively induces the intermolecular rearrangement of polymer macromolecules.

  9. Enhancement effect of irradiation by methotrexate

    SciTech Connect

    Shehata, W.M.; Meyer, R.L.

    1980-09-15

    Three cases are described in which complications developed which were believed to be due to the enhancement effect of irradiation by methotrexate during the course of therapy for lung, kidney, and bladder cancer. These included esophageal and large bowel complications. In two of these cases, the patients improved with conservative therapy.

  10. Minimizing material damage using low temperature irradiation

    NASA Astrophysics Data System (ADS)

    Craven, E.; Hasanain, F.; Winters, M.

    2012-08-01

    Scientific advancements in healthcare driven both by technological breakthroughs and an aging and increasingly obese population have lead to a changing medical device market. Complex products and devices are being developed to meet the demands of leading edge medical procedures. Specialized materials in these medical devices, including pharmaceuticals and biologics as well as exotic polymers present a challenge for radiation sterilization as many of these components cannot withstand conventional irradiation methods. The irradiation of materials at dry ice temperatures has emerged as a technique that can be used to decrease the radiation sensitivity of materials. The purpose of this study is to examine the effect of low temperature irradiation on a variety of polymer materials, and over a range of temperatures from 0 °C down to -80 °C. The effectiveness of microbial kill is also investigated under each of these conditions. The results of the study show that the effect of low temperature irradiation is material dependent and can alter the balance between crosslinking and chain scission of the polymer. Low temperatures also increase the dose required to achieve an equivalent microbiological kill, therefore dose setting exercises must be performed under the environmental conditions of use.

  11. Irradiation Processing Department monthly report, June 1962

    SciTech Connect

    Not Available

    1992-07-13

    This document details activities of the Irradiation Processing Department during the month of June, 1962. A general summary is included at the start of the report, after which the report is divided into the following sections: Research and Engineering Operations; Production and Reactor Operations; Facilities Engineering Operation; and NPR Project.

  12. Building X-ray tube based irradiators

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The construction of economical x-ray tube based irradiators in a variety of configurations is described using 1000 Watt x-ray tubes. Single tube, double tube, and four tube designs are described, as well as various cabinet construction techniques. Relatively high dose rates were achieved for small s...

  13. New pallet irradiation for Gammaster International

    NASA Astrophysics Data System (ADS)

    Möhlmann, Mr. J. H. F.

    1993-07-01

    State of the art technology offers many opportunities to improve production process with ionizing radiation. Also the requirements to this process become more and more stringent; who was aware of the ISO-9000 Standards? Now it is a necessary concept? Internal and external audits, in particular by Regulatory Bodies such as the FDA and DHSS/MCA, are necessary and commonplace requirements when operating in the Healthcare and Pharmaceutical sectors. Efficiency is a major requirement for industry and also for our radiation business. With all the above mentioned items in mind, Gammaster International B.V. in close cooperation with Nordion International Inc. has developed and built a new type Pallet Irradiator. In this new concept, our 22 years experience in gamma processing and the expertise gained in 10 years of operation of pallet irradiators was incorporated. For this irradiator Gammaster International designed and built a new process control console, incorporating state of the art technology such as: - A well-balanced safety system - A control panel, with status indication for all essential operating and safety parameters - Advances warning for necessary maintenance work - Automatic timer-setting control in addition to an automatic timer setting modification - Clear indication of the position of the product inside the unit and its status - Fully automatic product information generated when the product leaves the irradiation unit - Visual process control with the help of a color monitor - Incremental dose-control - Fault identification

  14. Test procedure for Hasselblad field irradiance

    NASA Technical Reports Server (NTRS)

    George, C.

    1975-01-01

    The procedure is defined for determining the uniformity of film plane illumination (field irradiance) of the Hasselblad cameras. The data source shall consist of photographs, with X-Y scans being taken for indication only. The accuracy requirement is 2.0%.

  15. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... purification system designed to be capable of maintaining the water during normal operation at a conductivity..., irradiator pools must either: (1) Have a water-tight stainless steel liner or a liner metallurgically... water level that could allow water to drain out of the pool. Pipes that have intakes more than 0.5...

  16. 10 CFR 36.33 - Irradiator pools.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... purification system designed to be capable of maintaining the water during normal operation at a conductivity..., irradiator pools must either: (1) Have a water-tight stainless steel liner or a liner metallurgically... water level that could allow water to drain out of the pool. Pipes that have intakes more than 0.5...

  17. X-ray irradiation of yeast cells

    NASA Astrophysics Data System (ADS)

    Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

    1997-10-01

    Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

  18. Localized comedo formation after cobalt irradiation

    SciTech Connect

    Myskowski, P.L.; Safai, B.

    1981-10-01

    Following Cobalt-60 irradiation for a left frontotemporal tumor, a 61-year-old woman developed comedones on the forehead. These changes responded to conventional acne therapy with retinoic acid. Multiple acneigenic factors were implicated in the pathogenesis of her lesions.

  19. Food processing with electrically generated photon irradiation

    SciTech Connect

    Matthews, S.M.

    1983-01-01

    A conceptual design for a portable electric food irradiation processing machine is presented and analyzed for cost assuming the required accelerators are available for $1.5 million each. It is shown that food can be processed to 1 kGy for a price of $5.98/ton.

  20. The irradiation facility at the AGOR cyclotron

    NASA Astrophysics Data System (ADS)

    Brandenburg, Sytze; Ostendorf, Reint; Hofstee, Mariet; Kiewiet, Harry; Beijers, Hans

    2007-08-01

    The KVI is conducting radiobiology research using protons up to 190 MeV from the superconducting AGOR cyclotron in collaboration with the University Medical Center Groningen (UMCG) since 1998. Using the same set-up, we have started irradiations for radiation hardness studies of detectors and components for the European Space Agency (ESA) and industrial parties. For these irradiations, we use either mono-energetic protons or a simulated solar flare energy spectrum with fluxes up to 5 × 108 protons cm-2 s-1. Furthermore, tests of radiation effects such as single event upsets, are being performed with intensities down to a few particles/s. Different energies are achieved by degrading the primary beam energy. We are currently developing the capability for heavy ion irradiations in air with beams up to Xe at beam energies between 15 and 45 MeV per nucleon. Performing the irradiations in air simplifies handling and monitoring of the device under test. The high energy allows penetration to the active layer of electronic devices, without modifications to the chip housing. The different ions provide a wide range in LET.

  1. Microwave Irradiation on Halloysite-Polypropylene Nanocomposites

    NASA Astrophysics Data System (ADS)

    Espino, Omar; Yust, Brian; Chipara, Dorina; Ajayan, Pullickel; Chipara, Alin; Chipara, Mircea; Utrgv Collaboration; Rice Collaboration

    Halloysite is an unique cyllindrical nanoclay characterized by poor electrical and thermal conductivity, which may become the filler of choice for the reinforcement of polymeric matrix, where electrical or thermal insulation are required. The main limits in the use of halloysite as replacement for carbon nanotube (CNT) are: 1. Smaller aspect ratio as halloysites are typically shorter than CNTs. 2. Smaller Young modulus of halloysites compared with CNTs. 3. Reduced thermal stability due to the loss of water upon heating. A research on halloysite dispersed within isotactic polypropylene is reported. To improve the interface between the halloysite and the polymeric matrix a microwave irradiation step has been considered. The local heating of the halloysite nanotubes is mediated by the absorbed/structural water content of the nanoclay. Nanocomposites loaded by various amounts of halloysite ranging from 0 % to 20 % wt. have been prepared by melt mixing by using a Haake RheoMixer. The as obtained nanocomposites have been subjected to microwave irradiation at 75 W in an Anton Paar Monowave 300 system and various irradiation times ranging from 5, 10, 15, 30, 45, and 60 minutes. The effect of microwave irradiation has been studied by Raman and FTIR spectroscopy

  2. Continuous wave laser irradiation of explosives

    SciTech Connect

    McGrane, Shawn D.; Moore, David S.

    2010-12-01

    Quantitative measurements of the levels of continuous wave (CW) laser light that can be safely applied to bare explosives during contact operations were obtained at 532 nm, 785 nm, and 1550 nm wavelengths. A thermal camera was used to record the temperature of explosive pressed pellets and single crystals while they were irradiated using a measured laser power and laser spot size. A visible light image of the sample surface was obtained before and after the laser irradiation. Laser irradiation thresholds were obtained for the onset of any visible change to the explosive sample and for the onset of any visible chemical reaction. Deflagration to detonation transitions were not observed using any of these CW laser wavelengths on single crystals or pressed pellets in the unconfined geometry tested. Except for the photochemistry of DAAF, TATB and PBX 9502, all reactions appeared to be thermal using a 532 nm wavelength laser. For a 1550 nm wavelength laser, no photochemistry was evident, but the laser power thresholds for thermal damage in some of the materials were significantly lower than for the 532 nm laser wavelength. No reactions were observed in any of the studied explosives using the available 300 mW laser at 785 nm wavelength. Tables of laser irradiance damage and reaction thresholds are presented for pressed pellets of PBX9501, PBX9502, Composition B, HMX, TATB, RDX, DAAF, PETN, and TNT and single crystals of RDX, HMX, and PETN for each of the laser wavelengths.

  3. Strain engineering in graphene by laser irradiation

    SciTech Connect

    Papasimakis, N.; Mailis, S.; Huang, C. C.; Al-Saab, F.; Hewak, D. W.; Luo, Z.; Shen, Z. X.

    2015-02-09

    We demonstrate that the Raman spectrum of graphene on lithium niobate can be controlled locally by continuous exposure to laser irradiation. We interpret our results in terms of changes to doping and mechanical strain and show that our observations are consistent with light-induced gradual strain relaxation in the graphene layer.

  4. gamma-Irradiation of PEGd,lPLA and PEG-PLGA multiblock copolymers. I. Effect of irradiation doses.

    PubMed

    Dorati, R; Colonna, C; Serra, M; Genta, I; Modena, T; Pavanetto, F; Perugini, P; Conti, B

    2008-01-01

    To evaluate the effects of different gamma irradiation doses on PEGd,lPLA and PEG-PLGA multiblock copolymers. The behaviour of the multiblock copolymers to irradiation was compared to that of PLA, PLGA polymers. PEGd,lPLA, PEG-PLGA, PLA and PLGA polymers were irradiated by using a (60)Co irradiation source at 5, 15, 25 and 50 kGy total dose. Characterization was performed on all samples before and after irradiation, by nuclear magnetic resonance (NMR), infrared absorption spectrophotometry (FTIR) and gel permeation chromatography (GPC). The effect of gamma irradiation on polymer stability was also evaluated. Results of NMR and FTIR suggest an increase in -OH and -COOH groups, attributed to scission reactions induced by irradiation treatment. Data of GPC analysis showed that the weight average molecular weight (Mw) of polymer samples decreased with increasing irradiation dose. The extent of Mw degradation expressed as percentage of Mw reduction was more prominent for polymers with high molecular weight as PEGd,lPLA and PLA. The dominant effect of gamma-irradiation on both polymer samples was chain scission. The multiblock copolymer PEGd,lPLA presented higher sensitivity to irradiation treatment with respect to PLA, likely due to the presence of PEG in the matrix. The effect of gamma irradiation continues over a much longer period of time after gamma irradiation has been performed. It is suggested that the material reacts with oxygen to form peroxyl free radicals, which may further undergo degradation reactions during storage after irradiation. PMID:18528761

  5. In vitro irradiation system for radiobiological experiments

    PubMed Central

    2013-01-01

    Background Although two-dimensional (2-D) monolayer cell cultures provide important information on basic tumor biology and radiobiology, they are not representative of the complexity of three-dimensional (3-D) solid tumors. In particular, new models reproducing clinical conditions as closely as possible are needed for radiobiological studies to provide information that can be translated from bench to bedside. Methods We developed a novel system for the irradiation, under sterile conditions, of 3-D tumor spheroids, the in vitro model considered as a bridge between the complex architectural organization of in vivo tumors and the very simple one of in vitro monolayer cell cultures. The system exploits the same equipment as that used for patient treatments, without the need for dedicated and highly expensive instruments. To mimic the passage of radiation beams through human tissues before they reach the target tumor mass, 96-multiwell plates containing the multicellular tumor spheroids (MCTS) are inserted into a custom-built phantom made of plexiglass, the material most similar to water, the main component of human tissue. Results The system was used to irradiate CAEP- and A549-derived MCTS, pre-treated or not with 20 μM cisplatin, with a dose of 20 Gy delivered in one session. We also tested the same treatment schemes on monolayer CAEP and A549 cells. Our preliminary results indicated a significant increment in radiotoxicity 20 days after the end of irradiation in the CAEP spheroids pre-treated with cisplatin compared to those treated with cisplatin or irradiation alone. Conversely, the effect of the radio- chemotherapy combination in A549-derived MCTS was similar to that induced by cisplatin or irradiation alone. Finally, the 20 Gy dose did not affect cell survival in monolayer CAEP and A549 cells, whereas cisplatin or cisplatin plus radiation caused 100% cell death, regardless of the type of cell line used. Conclusions We set up a system for the irradiation

  6. Effects and consequences of prenatal irradiation.

    PubMed

    Vos, O

    1989-06-01

    After a brief introduction about the historic development of risk estimates and maximum permissible doses of ionizing radiation, the risks of prenatal irradiation are discussed. Experimental data mainly obtained with mice indicate that the most important risk exists during the period of organogenesis and concerns the induction of malformations. Although in man this period lies between about 10 and 80 days after fertilization for most organs, the main development of the brain occurs later, namely between the 8th and 15th week after conception. Data from Japanese victims of the atomic bomb explosions above Hiroshima and Nagasaki indicate that during development the brain is the most sensitive organ to irradiation and maximal sensitivity is found between the 8th and 15th week after fertilization. A dose of one Gray received during this period induces a severe mental retardation in about 45% of the newborns. The dose response relationship is not significantly different from a linear one without a threshold dose. Studies of intelligence and school performance have shown that 1 Gray received during the 8th-15th week causes a shift of the average intelligence of about 30 points. Irradiation before the 8th week and after the 25th week had no effect on intelligence or mental retardation. During the 16th and 25th week sensitivity was about one fourth of that during the 8th-15th week. Although the irradiation of the embryo and fetus should be avoided as much as possible, the new data have led to an abandonment of the so-called 10-day rule. Generally an accidental irradiation of the embryo or fetus of less than 5 cGy is not considered as a medical indication for abortion. Retrospective studies showed that mothers from children who died from leukemia or other childhood tumors, had been subjected to a diagnostic irradiation of the pelvis or lower abdomen more frequently than mothers from children that did not develop a tumor. It has been estimated that prenatal sensitivity for

  7. Calibration of the Odyssey Photosynthetic Irradiance Recorder for Absolute Irradiance Measures

    EPA Science Inventory

    Researchers are increasingly interested in measuring hotosynthetically active radiation (PAR) because of its importance in determining the structure and function of lotic ecosystems. The Odyssey Photosynthetic Irradiance Recorder is an affordable PAR meter gaining popularity am...

  8. IRRADIATION EFFECTS ON THE PHYSICAL CHARACTERISTICS OF SEWAGE SLUDGE

    SciTech Connect

    Lee, M-J.; Lee, J-K.; Yoo, D-H.; Ho, K.

    2004-10-05

    The radiation effects on the physical characteristic of the sewage sludge were studied in order to obtain information which will be used for study on the enhancement of the sludge's dewaterability. Water contents, capillary suction time, zeta potential, irradiation dose, sludge acidity, total solid concentration, sludge particle size and microbiology before and after irradiation were investigated. Irradiation gave an effect on physical characteristics sludge. Water content in sludge cake could be reduced by irradiation at the dose of 10kGy.

  9. Optical imaging of irradiated and non-irradiated hearts (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Bolin, Stephanie; Chen, Guanchu; Medhora, Meetha M.; Camara, Amadou K. S.; Ranji, Mahsa

    2016-03-01

    Objective: In this study, the metabolic state of the heart tissue is studied in a rodent model of ischemia and reperfusion (IR) in rats exposed to irradiation injury using a cryofluorescence imaging technique. Mitochondrial metabolic state is evaluated by autofluorescence of mitochondrial metabolic coenzymes NADH and FAD. The redox ratio (NADH/FAD) is used as a biochemical/metabolic marker of oxidative stress, before, during and after IR. Materials and methods: Hearts were extracted from non-irradiated (control) and irradiated rats (Irr) given 15 Gy whole thorax irradiation rats (WTI). After 35 days, before the onset of radiation pneumonitis, these two groups of hearts were subjected to one of three treatments; Time control (TC; hearts perfused for the duration of the protocol without ischemia or IR), 25 minutes ischemia with no reperfusion and 25 minutes ischemia followed by 60 minutes reperfusion (IR). Hearts were removed from the Langendorff perfusion system and immediately snap frozen in liquid N2 to preserve the metabolic state after injury; 3-dimensional (3D) cryo-fluorescent imager was used to obtain in fixed time NADH and FAD fluorescence images and their distribution across the entire ventricles. In this study, a 30-μm axial resolution was used resulting in 550 cross-section images per heart. The 3D images of the redox ratio and their respective histograms were calculated in the six groups of hearts. Results: We compared the mean values of the redox ratio in each group, which demonstrate a reduced mitochondrial redox state in both irradiated and non-irradiated ischemic hearts and an oxidized mitochondrial redox state for both irradiated and non-irradiated ischemia-reperfusion hearts compared to control hearts. For non-irradiated hearts, ischemia and IR injuries resulted respectively in 61% increase and 54% decrease in redox ratio when compared with TC. For irradiated hearts, ischemia and IR injuries resulted respectively in 90% increase and 50% decrease

  10. Experimental plan for irradiation experiment HRB-21

    SciTech Connect

    Goodin, D. T.; Kania, M. J.; Patton, B. W.

    1989-04-01

    Irradiation experiment HRB-21 is the first in a series of test capsules that are designed to provide a fuel-performance data base to be used for the validation of modular high-temperature gas-cooled reactor (MHTGR) coated-particle fuel performance models under MHTGR normal operating conditions and specific licensing basis events. Capsule HRB-21 will contain an advanced TRISO-P UCO/ThO{sub 2} - coated-particle fuel system with demonstrated low defective-particle fraction ({le}5 {times} 10{sup {minus}5}) and a heavy metal-contamination fraction ({le}1 {times} 10{sup {minus}5}) that meets MHTGR quality specifications. The coated particles and fuel compacts were fabricated in laboratory-scale facilities using MHTGR reference procedures at General Atomics (GA). Nearly 150,000 fissile and fertile particles will be irradiated in capsule HRB-21 at a mean volumetric fuel temperature of 975{degree}C and will achieve a peak fissile burnup of 26% fissions per initial metal atom (FIMA) while accumulating a fast neutron fluence of about 4.5 {times} 10{sup 25} neutrons/m{sup 2}. This experiment is a cooperative effort between the US Department of Energy (DOE) and the Japan Atomic Energy Research Institute (JAERI). The participants are the Oak Ridge National Laboratory (ORNL), GA, and the Tokai Research Establishment. Capsule HRB-21 will contain the US MHTGR fuel specimens, and a companion capsule, HRB-22, will contain the JAERI fuel. The irradiation will take place in the removable beryllium reflector facility of the High Flux Isotope Reactor (HFIR) at ORNL. The performance of the fuel during irradiation will be closely monitored through on-line fission gas release measurements. Detailed postirradiation examination and conduction cooldown simulation testing will be performed on the irradiated fuel compacts from both the HRB-21 and HRB-22 capsules. 5 refs., 9 figs., 6 tabs.

  11. Ionospheric Change and Solar EUV Irradiance

    NASA Astrophysics Data System (ADS)

    Sojka, J. J.; David, M.; Jensen, J. B.; Schunk, R. W.

    2011-12-01

    The ionosphere has been quantitatively monitored for the past six solar cycles. The past few years of observations are showing trends that differ from the prior cycles! Our good statistical relationships between the solar radio flux index at 10.7 cm, the solar EUV Irradiance, and the ionospheric F-layer peak density are showing indications of divergence! Present day discussion of the Sun-Earth entering a Dalton Minimum would suggest change is occurring in the Sun, as the driver, followed by the Earth, as the receptor. The dayside ionosphere is driven by the solar EUV Irradiance. But different components of this spectrum affect the ionospheric layers differently. For a first time the continuous high cadence EUV spectra from the SDO EVE instrument enable ionospheric scientists the opportunity to evaluate solar EUV variability as a driver of ionospheric variability. A definitive understanding of which spectral components are responsible for the E- and F-layers of the ionosphere will enable assessments of how over 50 years of ionospheric observations, the solar EUV Irradiance has changed. If indeed the evidence suggesting the Sun-Earth system is entering a Dalton Minimum periods is correct, then the comprehensive EVE solar EUV Irradiance data base combined with the ongoing ionospheric data bases will provide a most fortuitous fiduciary reference baseline for Sun-Earth dependencies. Using the EVE EUV Irradiances, a physics based ionospheric model (TDIM), and 50 plus years of ionospheric observation from Wallops Island (Virginia) the above Sun-Earth ionospheric relationship will be reported on.

  12. Progress of food irradiation in the United States

    NASA Astrophysics Data System (ADS)

    Derr, D. D.; Engeljohn, D. L.; Griffin, R. L.

    1995-02-01

    Irradiated foods have not yet made a significant impact in the United States marketplace. What progress has occurred to facilitate their commercialization? Irradiated produce has been sold in small quantities since 1992 and irradiated poultry was introduced in the marketplace in 1993. Federal inspection of irradiated commodities has settled into a regular routine. What must occur to further expand irradiated foods in the marketplace? Petitions to permit irradiation of red meats and seafood are being considered by the Food and Drug Administration (FDA) and a petition to permit the irradiation of shell eggs is being prepared for submission to FDA. In addition, the U.S. Department of Agriculture (USDA) has accelerated efforts to develop the policies and regulatory structure needed to facilitate the approval of new irradiation treatments for imported plant products regulated by quarantine. When will greater commercialization occur? More positive coverage to food irradiation in recent months by both the trade and popular press indicates a change in attitude towards irradiated foods by both consumers and the food industry. Finally, actual consumer response to available irradiated foods casts a favorable light on the potential for increased marketing of value-added irradiated foods.

  13. Detection of low amount of irradiated ingredients in non-irradiated precooked meals

    NASA Astrophysics Data System (ADS)

    Marchioni, Eric; Horvatovich, Peter; Ndiaye, Bara; Miesch, Michel; Hasselmann, Claude

    2002-03-01

    The application of the European Standards for the detection of irradiated food by thermoluminescence of silicates, electron-spin resonance spectroscopy of bones or gas chromatography-mass spectrometry of 2-alkylcyclobutanones does not allow the detection of irradiated ingredients included in small quantity in the matrix of a food which has not been irradiated, but which could be subjected to various processing technologies such as cooking, freezing or storage. The use of an enzymatic food hydrolysis carried out at moderated temperature, for the extraction of the food-contaminating silicate minerals and bone fragments, followed by a purification of the extracts by a high-density aqueous solution of sodium polytungstate, allows a simultaneous detection of weak inclusions (0.1% m:m) of irradiated spices and mechanically deboned turkey meat (MRM) included in various precooked foods. Moreover, the use of a supercritical fluid extraction procedure for the 2-alkylcyclobutanones or an additional purification step of the lipid extracts made it possible to lower the detection limit of the 2-alkylcyclobutanones radiation-induced from triglycerides. Using gas chromatography-mass spectrometry, down to 0.5% (m:m) of irradiated MRM included in non-irradiated chicken quenelles could be detected.

  14. Irradiation creep of various ferritic alloys irradiated {approximately}400 C in the PFR and FFTF reactors

    SciTech Connect

    Toloczko, M.B.; Garner, F.A.; Eiholzer, C.R.

    1998-03-01

    Three ferritic alloys were irradiated in two fast reactors to doses of 50 dpa or more at temperatures near 400 C. One martensitic alloy, HT9, was irradiated in both the FFTF and PFR reactors. PFR is the Prototype Fast Reactor in Dourneay, Scotland, and FFTF is the Fast Flux Test Facility in Richland, WA. D57 is a developmental alloy that was irradiated in PFR only, and MA957 is a Y{sub 2}O{sub 3} dispersion-hardened ferritic alloy that was irradiated only in FFTF. These alloys exhibited little or no void swelling at {approximately}400 C. Depending on the alloy starting condition, these steels develop a variety of non-creep strains early in the irradiation that are associated with phase changes. Each of these alloys creeps at a rate that is significantly lower than that of austenitic steels irradiated in the same experiments. The creep compliance for ferritic alloys in general appears to be {approximately}0.5 {times} 10{sup {minus}6} MPa{sup {minus}1} dpa{sup {minus}1}, independent of both composition and starting state. The addition of Y{sub 2}O{sub 3} as a dispersoid does not appear to change the creep behavior.

  15. The Irradiation Performance and Microstructural Evolution in 9Cr-2W Steel Under Ion Irradiation

    NASA Astrophysics Data System (ADS)

    Alsagabi, Sultan; Charit, Indrajit; Pasebani, Somayeh

    2016-02-01

    Grade 92 steel (9Cr-2W) is a ferritic-martensitic steel with good mechanical and thermal properties. It is being considered for structural applications in Generation IV reactors. Still, the irradiation performance of this alloy needs more investigation as a result of the limited available data. The irradiation performance investigation of Grade 92 steel would contribute to the understanding of engineering aspects including feasibility of application, economy, and maintenance. In this study, Grade 92 steel was irradiated by iron ion beam to 10, 50, and 100 dpa at 30 and 500 °C. In general, the samples exhibited good radiation damage resistance at these testing parameters. The radiation-induced hardening was higher at 30 °C with higher dislocation density; however, the dislocation density was less pronounced at higher temperature. Moreover, the irradiated samples at 30 °C had defect clusters and their density increased at higher doses. On the other hand, dislocation loops were found in the irradiated sample at 50 dpa and 500 °C. Further, the irradiated samples did not show any bubble or void.

  16. Effect of low-level laser irradiating point on immunity

    NASA Astrophysics Data System (ADS)

    Cai, ChangSong; Qi, Qiong-fang; Xin, Jiang

    1993-03-01

    This paper reports that cellular immune function was observed when He-Ne laser was used to irradiate `zusanli' point in rats using various power, time, and periods. The indicator was a lymphocyte transformation test (LTT) by MTT colorimetric analysis. The best irradiating condition was determined, the effect and both virtues and defects of the laser were compared with those of electropuncture. The results show (1) LTT was enhanced in the group of laser irradiating point, but LTT was not enhanced in non-point (t' test, P < 0.01). (2) Lower power -- 2 mW or 5 mW of irradiating for 15 - 20 min, was better; 10 mW or 20 mW of irradiating for 10 - 15 min was suitable. Prolonged irradiating time did not enhance the immune function of the rats. On the contrary, immune function was inhibited. (3) A 7-day period of irradiating was best (once a day, 10 mW for 10 min). Enhanced LTT was not seen when irradiation days were added (SNK, P > 0.05). (4) Laser irradiation point and electropuncture were compared with vehicle control, LTT in the former two groups was enhanced significantly (ANOVA, P < 0.01), and laser irradiating point and electropuncture had the same effect (SNK, P > 0.05). The data suggest that laser irradiating point was able to enhance cell immunity and the enhancement of LTT had a point specific characteristic. The best condition of laser irradiating point was 2 mW for 15 - 20 min, and 10 mW or 20 mW for 10 - 15 min. The best period was 7-day irradiation. The results show laser irradiating the point may activate the main and collateral channels system, then modify the immune function of the body. Our observations provide experimental evidence for proper clinical application of laser irradiating points. The paper theoretically discusses and analyzes the experiment results in detail.

  17. Development of radiation indicators to distinguish between irradiated and non-irradiated herbal medicines using HPLC and GC-MS.

    PubMed

    Kim, Min Jung; Ki, Hyeon A; Kim, Won Young; Pal, Sukdeb; Kim, Byeong Keun; Kang, Woo Suk; Song, Joon Myong

    2010-09-01

    The effects of high dose γ-irradiation on six herbal medicines were investigated using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). Herbal medicines were irradiated at 0-50 kGy with (60)Co irradiator. HPLC was used to quantify changes of major components including glycyrrhizin, cinnamic acid, poncirin, hesperidin, berberine, and amygdalin in licorice, cinnamon bark, poncirin immature fruit, citrus unshiu peel, coptis rhizome, and apricot kernel. No significant differences were found between gamma-irradiated and non-irradiated samples with regard to the amounts of glycyrrhizin, berberine, and amygdalin. However, the contents of cinnamic acid, poncirin, and hesperidin were increased after irradiation. Volatile compounds were analyzed by GC/MS. The relative proportion of ketone in licorice was diminished after irradiation. The relative amount of hydrocarbons in irradiated cinnamon bark and apricot kernel was higher than that in non-irradiated samples. Therefore, ketone in licorice and hydrocarbons in cinnamon bark and apricot kernel can be considered radiolytic markers. Three unsaturated hydrocarbons, i.e., 1,7,10-hexadecatriene, 6,9-heptadecadiene, and 8-heptadecene, were detected only in apricot kernels irradiated at 25 and 50 kGy. These three hydrocarbons could be used as radiolytic markers to distinguish between irradiated (>25 kGy) and non-irradiated apricot kernels. PMID:20623272

  18. Stage III and localized stage IV breast cancer: irradiation alone vs irradiation plus surgery

    SciTech Connect

    Bedwinek, J.; Rao, V.; Perez, C.; Lee, J.; Fineberg, B.

    1981-01-01

    One hundred forty-seven patients with non-inflammatory, Stage III and IV breast cancer were treated with irradiation alone (54 patients) or with a combination of irradiation and mastectomy (93 patients). In the T/sub 3/ category, the local failure rate was 45% (5/11) for the irradiation alone patients vs 12% (3/25) for the irradiation plus surgery patients; in the T/sub 4/ category these figures were 65% (28/43) vs 13% (9/68), respectively. Corresponding local failure rates by size of primary tumor were 50% (2/4) vs 15% (5/29) for tumors 0-5 cm, 43% (0/21) vs 14% (6/45) for 5-8 cm tumors, and 75% (22/29) vs 5% (1/20) for tumors greater than or equal to8 cm. The rates of regional failure for the two treatment methods were compared according to N stage; they were 9% (2/23) for irradiation alone vs 11% (8/76) for irradiation plus surgery in the N/sub 0//sub -//sub 1/ category, and 58% (18/31) vs 18% (3/17), respectively, for the N/sub 2//sub -//sub 3/ category. A dose response analysis for patients with tumors greater than 5 cm treated with irradiation alone did not show a decrease in local failure rate with increasing total tumor dose over a range of 4000 to 7000 rad, suggesting that doses in this range are too low for these large tumors. Since a significant late complication rate has been reported with doses higher than this, patients with non-inflammatory, but large (>5 cm) tumors, should be treated with a combination of surgery and irradiation whenever possible to achieve maximum local-regional control with a minimum probability of complications. In 36 patients with inflammatory carcinoma, the rates of local and regional failure were 52% (15/29) and 38% (11/29), respectively, for patients treated with irradiation alone, and 14% (1/7) and 29% (2/7), respectively, for patients receiving irradiation plus surgery.

  19. Advanced Numerical Model for Irradiated Concrete

    SciTech Connect

    Giorla, Alain B.

    2015-03-01

    In this report, we establish a numerical model for concrete exposed to irradiation to address these three critical points. The model accounts for creep in the cement paste and its coupling with damage, temperature and relative humidity. The shift in failure mode with the loading rate is also properly represented. The numerical model for creep has been validated and calibrated against different experiments in the literature [Wittmann, 1970, Le Roy, 1995]. Results from a simplified model are shown to showcase the ability of numerical homogenization to simulate irradiation effects in concrete. In future works, the complete model will be applied to the analysis of the irradiation experiments of Elleuch et al. [1972] and Kelly et al. [1969]. This requires a careful examination of the experimental environmental conditions as in both cases certain critical information are missing, including the relative humidity history. A sensitivity analysis will be conducted to provide lower and upper bounds of the concrete expansion under irradiation, and check if the scatter in the simulated results matches the one found in experiments. The numerical and experimental results will be compared in terms of expansion and loss of mechanical stiffness and strength. Both effects should be captured accordingly by the model to validate it. Once the model has been validated on these two experiments, it can be applied to simulate concrete from nuclear power plants. To do so, the materials used in these concrete must be as well characterized as possible. The main parameters required are the mechanical properties of each constituent in the concrete (aggregates, cement paste), namely the elastic modulus, the creep properties, the tensile and compressive strength, the thermal expansion coefficient, and the drying shrinkage. These can be either measured experimentally, estimated from the initial composition in the case of cement paste, or back-calculated from mechanical tests on concrete. If some

  20. Planarian Immobilization, Partial Irradiation, and Tissue Transplantation

    PubMed Central

    Guedelhoefer IV, Otto C.; Sánchez Alvarado, Alejandro

    2012-01-01

    The planarian, a freshwater flatworm, has proven to be a powerful system for dissecting metazoan regeneration and stem cell biology1,2. Planarian regeneration of any missing or damaged tissues is made possible by adult stem cells termed neoblasts3. Although these stem cells have been definitively shown to be pluripotent and singularly capable of reconstituting an entire animal4, the heterogeneity within the stem cell population and the dynamics of their cellular behaviors remain largely unresolved. Due to the large number and wide distribution of stem cells throughout the planarian body plan, advanced methods for manipulating subpopulations of stem cells for molecular and functional study in vivo are needed. Tissue transplantation and partial irradiation are two methods by which a subpopulation of planarian stem cells can be isolated for further study. Each technique has distinct advantages. Tissue transplantation allows for the introduction of stem cells, into a naïve host, that are either inherently genetically distinct or have been previously treated pharmacologically. Alternatively, partial irradiation allows for the isolation of stem cells within a host, juxtaposed to tissue devoid of stem cells, without the introduction of a wound or any breech in tissue integrity. Using these two methods, one can investigate the cell autonomous and non-autonomous factors that control stem cell functions, such as proliferation, differentiation, and migration. Both tissue transplantation5,6 and partial irradiation7 have been used historically in defining many of the questions about planarian regeneration that remain under study today. However, these techniques have remained underused due to the laborious and inconsistent nature of previous methods. The protocols presented here represent a large step forward in decreasing the time and effort necessary to reproducibly generate large numbers of grafted or partially irradiated animals with efficacies approaching 100 percent. We

  1. Two Person Zero-Sum Semi-Markov Games with Unknown Holding Times Distribution on One Side: A Discounted Payoff Criterion

    SciTech Connect

    Minjarez-Sosa, J. Adolfo Luque-Vasquez, Fernando

    2008-06-15

    This paper deals with two person zero-sum semi-Markov games with a possibly unbounded payoff function, under a discounted payoff criterion. Assuming that the distribution of the holding times H is unknown for one of the players, we combine suitable methods of statistical estimation of H with control procedures to construct an asymptotically discount optimal pair of strategies.

  2. Planar asymmetric lipid bilayers of glycosphingolipid or lipopolysaccharide on one side and phospholipids on the other: membrane potential, porin function, and complement activation.

    PubMed Central

    Wiese, A; Reiners, J O; Brandenburg, K; Kawahara, K; Zähringer, U; Seydel, U

    1996-01-01

    We have determined some physicochemical properties of the monosaccharide-type fraction (GSL-1) of glycosphingolipids, the major glycolipid components of the outer leaflet of the Gram-negative species Sphingomonas paucimobilis. These properties included the state of order of the hydrocarbon moiety, the effective molecular area, surface charge density, and intrinsic transmembrane potential profile of reconstituted planar asymmetric GSL-1/phospholipid bilayer membranes. We have, furthermore, investigated the insertion into and the function of porin channels in the reconstituted bilayers and the complement-activating capability of GSL-1 surfaces. All results were compared with respective data for deep rough mutant lipopolysaccharide of Salmonella minnesota R595. We found a remarkable agreement in most functional properties of the two glycolipids. PMID:8770208

  3. Numerical prediction of a turbulent separated and reattaching flow in a 2-D plane channel with a one-sided abrupt expansion

    NASA Astrophysics Data System (ADS)

    Matsunaga, Akio; Kasagi, Nobuhide

    1993-09-01

    A turbulent separated and reattaching flow was predicted with several, including two low-Reynolds number, kappa-epsilon models. These results were compared with the experimental result that was obtained through the use of three-dimensional particle tracking velocimetry. Although the standard model generally gives better results than the low-Reynolds model in the separated free shear layer, the latter works better in the near-wall region. Further improvement in the low-Reynolds kappa-epsilon model, particularly in the model parameters, should make its prediction of turbulent flows with separation and reattachment accurate enough for engineering applications.

  4. 'A one-sided affair': unilateral pulmonary oedema and the role of cardiac MRI in diagnosing premature coronary artery disease in a patient with Prader-Willi syndrome.

    PubMed

    Jabbar, Avais; Khan, Jamal N; Singh, Anvesha; McCann, Gerry P

    2013-01-01

    There is no formal association between premature coronary artery disease (CAD) and Prader-Willi syndrome despite its association with hyperlipidaemia, diabetes mellitus and hypertension. A 36-year-old man with Prader-Willi syndrome presented with acute breathlessness. Inflammatory markers were borderline elevated and chest radiography demonstrated unilateral diffuse alveolar shadowing. Bronchopneumonia was diagnosed and despite treatment with multiple courses of antimicrobial therapy, there was minimal symptomatic and radiographical improvement. A diagnosis of unilateral pulmonary oedema was suspected. Echocardiography was non-diagnostic due to body habitus and coronary angiography was deemed inappropriate due to uncertainty in diagnosis, invasiveness and pre-existing chronic kidney disease. Therefore, cardiac magnetic resonance was performed, confirming severe triple-vessel CAD. This case demonstrates a presentation of heart failure with unilateral chest radiograph changes in a young patient with Prader-Willi syndrome and severe premature CAD detected by multiparametric cardiac magnetic resonance imaging. PMID:23704427

  5. Spectral irradiance standard for the ultraviolet - The deuterium lamp

    NASA Technical Reports Server (NTRS)

    Saunders, R. D.; Ott, W. R.; Bridges, J. M.

    1978-01-01

    A set of deuterium lamps is calibrated as spectral irradiance standards in the 200-350-nm spectral region utilizing both a high accuracy tungsten spectral irradiance standard and a newly developed argon mini-arc spectral radiance standard. The method which enables a transfer from a spectral radiance to a spectral irradiance standard is described. The following characteristics of the deuterium lamp irradiance standard are determined: sensitivity to alignment; dependence on input power and solid angle; reproducibility; and stability. The absolute spectral radiance is also measured in the 167-330-nm region. Based upon these measurements, values of the spectral irradiance below 200 nm are obtained through extrapolation.

  6. Mechanical properties of UV irradiated rat tail tendon (RTT) collagen.

    PubMed

    Sionkowska, Alina; Wess, Tim

    2004-04-01

    The mechanical properties of RTT collagen tendon before and after UV irradiation have been investigated by mechanical testing (Instron). Air-dried tendon were submitted to treatment with UV irradiation (wavelength 254 nm) for different time intervals. The changes in such mechanical properties as breaking strength and percentage elongation have been investigated. The results have shown, that the mechanical properties of the tendon were greatly affected by time of UV irradiation. Ultimate tensile strength and ultimate percentage elongation decreased after UV irradiation of the tendon. Increasing UV irradiation leads to a decrease in Young's modulus of the tendon. PMID:15178003

  7. Structural changes of polytetrafluoroethylene during irradiation in oxygen

    NASA Astrophysics Data System (ADS)

    Liu, Shuling; Fu, Congli; Gu, Aiqun; Yu, Zili

    2015-04-01

    To study the effect of irradiation on PTFE structure and prepare modified PTFE micropowder, PTFE was irradiated with dose up to 4 MGy in oxygen at room temperature. The structures of both irradiated and unirradiated PTFE samples were comparatively characterized by IR, XPS, Raman spectra and XRD measurement. The results showed that new groups of acyl fluoride (COF), carboxylic acid (COOH) and trifluoromethyl (CF3) were formed under heavy radiation exposure in oxygen. In addition, the expansion of crystallite size or crystal lattice was first reported for the irradiated PTFE. The formation of new chemical groups and the expansion of crystallite size were elucidated by structural changes occurring in irradiation.

  8. Application of gamma irradiation for inhibition of food allergy

    NASA Astrophysics Data System (ADS)

    Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

    2002-03-01

    This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

  9. Silicon/HfO2 interface: Effects of gamma irradiation

    NASA Astrophysics Data System (ADS)

    Maurya, Savita

    2016-05-01

    Quality of MOS devices is a strong function of substrate and oxide interface. In this work we have studied how gamma photon irradiation affects the interface of a 13 nm thick, atomic layer deposited hafnium dioxide deposited on silicon wafer. CV and GV measurements have been done for pristine and irradiated samples to quantify the effect of gamma photon irradiation. Gamma photon irradiation not only introduces positive charge in the oxide and at the interface of Si/HfO2 interface but also induce phase change of oxide layer. Maximum oxide capacitances are affected by gamma photon irradiation.

  10. Influence of gamma ray irradiation on metakaolin based sodium geopolymer

    NASA Astrophysics Data System (ADS)

    Lambertin, D.; Boher, C.; Dannoux-Papin, A.; Galliez, K.; Rooses, A.; Frizon, F.

    2013-11-01

    Effects of gamma irradiation on metakaolin based Na-geopolymer have been investigated by external irradiation. The experiments were carried out in a gamma irradiator with 60Co sources up to 1000 kGy. Various Na-geopolymer with three H2O/Na2O ratios have been studied in terms of hydrogen radiolytic yield. The results show that hydrogen production increases linearly with water content. Gamma irradiation effects on Na-geopolymer microstructure have been investigated with porosity measurements and X-ray pair distribution function analysis. A change of pore size distribution and a structural relaxation have been found after gamma ray irradiation.

  11. VUV irradiation studies of plasmid DNA in aqueous solution

    NASA Astrophysics Data System (ADS)

    Śmialek, M. A.; Hoffmann, S. V.; Folkard, M.; Prise, K. M.; Shuker, D. E. G.; Braithwaite, N. S.; Mason, N. J.

    2008-02-01

    Interactions of VUV light and DNA samples in aqueous solutions are reported. The damage induced by such radiation is quantified by monitoring both loss of supercoiled DNA and formation of single and double strand breaks using agarose gel electrophoresis. Irradiations were performed using synchrotron VUV photons of 130, 150, 170 and 190 nm. VUV irradiation experiments revealed enhanced damage upon irradiation with 170 nm photons as compared with irradiations with photons of 150 nm and 130 nm. Irradiations carried at 190 nm caused the least damage.

  12. Irradiation creep and swelling of various austenitic alloys irradiated in PFR and FFTF

    SciTech Connect

    Garner, F.A.; Toloczko, M.B.

    1996-10-01

    In order to use data from surrogate neutron spectra for fusion applications, it is necessary to analyze the impact of environmental differences on property development. This is of particular importance in the study of irradiation creep and its interactions with void swelling, especially with respect to the difficulty of separation of creep strains from various non-creep strains. As part of an on-going creep data rescue and analysis effort, the current study focuses on comparative irradiations conducted on identical gas-pressurized tubes produced and constructed in the United States from austenitic steels (20% CW 316 and 20% CW D9), but irradiated in either the Prototype Fast Reactor (PFR) in the United Kingdom or the Fast Flux Test Facility in the United States. In PFR, Demountable Subassemblies (DMSA) serving as heat pipes were used without active temperature control. In FFTF the specimens were irradiated with active ({+-}{degrees}5C) temperature control. Whereas the FFTF irradiations involved a series of successive side-by-side irradiation, measurement and reinsertion of the same series of tubes, the PFR experiment utilized simultaneous irradiation at two axial positions in the heat pipe to achieve different fluences at different flux levels. The smaller size of the DMSA also necessitated a separation of the tubes at a given flux level into two groups (low-stress and high-stress) at slightly different axial positions, where the flux between the two groups varied {le}10%. Of particular interest in this study was the potential impact of the two types of separation on the derivation of creep coefficients.

  13. Gamma irradiation influence on physical properties of milk proteins

    NASA Astrophysics Data System (ADS)

    Cieśla, K.; Salmieri, S.; Lacroix, M.; Tien, C. Le

    2004-09-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  14. Mechanical properties for irradiated face-centred cubic nanocrystalline metals

    PubMed Central

    Xiao, X. Z.; Song, D. K.; Chu, H. J.; Xue, J. M.; Duan, H. L.

    2015-01-01

    In this paper, a self-consistent plasticity theory is proposed to model the mechanical behaviours of irradiated face-centred cubic nanocrystalline metals. At the grain level, a tensorial crystal model with both irradiation and grain size effects is applied for the grain interior (GI), whereas both grain boundary (GB) sliding with irradiation effect and GB diffusion are considered in modelling the behaviours of GBs. The elastic-viscoplastic self-consistent method with considering grain size distribution is developed to transit the microscopic behaviour of individual grains to the macroscopic properties of nanocrystals (NCs). The proposed theory is applied to model the mechanical properties of irradiated NC copper, and the feasibility and efficiency have been validated by comparing with experimental data. Numerical results show that: (i) irradiation-induced defects can lead to irradiation hardening in the GIs, but the hardening effect decreases with the grain size due to the increasing absorption of defects by GBs. Meanwhile, the absorbed defects would make the GBs softer than the unirradiated case. (ii) There exists a critical grain size for irradiated NC metals, which separates the grain size into the irradiation hardening dominant region (above the critical size) and irradiation softening dominant region (below the critical size). (iii) The distribution of grain size has a significant influence on the mechanical behaviours of both irradiated and unirradiated NCs. The proposed model can offer a valid theoretical foundation to study the irradiation effect on NC materials. PMID:27547091

  15. Microarchitecture of irradiated bone: comparison with healthy bone

    NASA Astrophysics Data System (ADS)

    Bléry, Pauline; Amouriq, Yves; Guédon, Jeanpierre; Pilet, Paul; Normand, Nicolas; Durand, Nicolas; Espitalier, Florent; Arlicot, Aurore; Malard, Olivier; Weiss, Pierre

    2012-03-01

    The squamous cell carcinomas of the upper aero-digestive tract represent about ten percent of cancers. External radiation therapy leads to esthetic and functional consequences, and to a decrease of the bone mechanical abilities. For these patients, the oral prosthetic rehabilitation, including possibilities of dental implant placement, is difficult. The effects of radiotherapy on bone microarchitecture parameters are not well known. Thus, the purpose of this study is to assess the effects of external radiation on bone micro architecture in an experimental model of 25 rats using micro CT. 15 rats were irradiated on the hind limbs by a single dose of 20 Grays, and 10 rats were non irradiated. Images of irradiated and healthy bone were compared. Bone microarchitecture parameters (including trabecular thickness, trabecular number, trabecular separation, connectivity density and tissue and bone volume) between irradiated and non-irradiated bones were calculated and compared using a Mann and Whitney test. After 7 and 12 weeks, images of irradiated and healthy bone are different. Differences on the irradiated and the healthy bone populations exhibit a statistical significance. Trabecular number, connectivity density and closed porosity are less important on irradiated bone. Trabecular thickness and separation increase for irradiated bone. These parameters indicate a decrease of irradiated bone properties. Finally, the external irradiation induces changes on the bone micro architecture. This knowledge is of prime importance for better oral prosthetic rehabilitation, including implant placement.

  16. Irradiation creep in structural materials at ITER operating conditions

    SciTech Connect

    Grossbeck, M.L.

    1994-09-01

    Irradiation creep is plastic deformation of a material under the influence of irradiation and stress. Below the regime of thermal creep, there remains a deformation mechanism under irradiation that is weakly temperature dependent and clearly different from thermal creep. This is irradiation creep. Both stress and irradiation are required for irradiation creep. Irradiation creep studies for applications in the past focused mostly on liquid metal fast breeder reactors where temperatures are usually above 400{degrees}C. Fusion reactors, especially nearterm devices such as the ITER will have components operating at temperatures as low as 100{degrees}C exposed to high neutron fluxes. Theories of irradiation creep based on steady-state point defect concentrations do not predict significant irradiation creep deformation at these temperatures; however, data from research reactors show that irradiation creep strains at 60{degrees}C are as high or higher than at temperatures above 300{degrees}C for austenitic stainless steels. Irradiation creep of nickel has also been observed at cryogenic temperatures.

  17. Effect of gamma irradiation on ethylene-octene copolymers

    NASA Astrophysics Data System (ADS)

    Li, Jiuqiang; Peng, Jing; Qiao, Jinliang; Jin, Dongbin; Wei, Genshuan

    2002-03-01

    Two ethylene-octene copolymers (POE) were irradiated with 60Co gamma radiation and influence of irradiation atmosphere, absorbed dose and heat treatment of samples on the crosslinking were studied. Thermal properties and crystalline morphology of non-irradiated and irradiated POE were determined by using differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXS), respectively. The Charlesby-Pinner equation was used to describe the relationship between absorbed dose and sol fraction. The gel fraction of irradiated POE was lower and decreased with the increase of octene content when irradiated in oxygen, compared to irradiation in nitrogen atmosphere. The gel fraction increased significantly with the increasing of absorbed dose for the two copolymers. Heat treatment of samples prohibited the crosslinking of irradiated POE. The DSC results indicated that a subtle change of thermal properties of POE was observed before and after gamma irradiation at low dose. No change was found from the WAXS spectra of non-irradiated and irradiated POE. For heat-treating samples, the Charlesby-Pinner equation can not fit perfectly with the relationship between the sol fraction and absorbed dose, but it fits well with the crosslinking reaction of POE pellets.

  18. Stability of an injectable disulfiram formulation sterilized by gamma irradiation

    SciTech Connect

    Phillips, M.; Agarwal, R.P.; Brodeur, R.J.; Garagusi, V.F.; Mossman, K.L.

    1985-02-01

    Stability of an injectable disulfiram suspension sterilized by gamma(gamma) irradiation was tested. Single doses of disulfiram powder in plastic syringes were subjected to 50,000 rads of gamma radiation. Culture media were inoculated with the irradiated drug to test for growth of bacteria, fungi, and mycobacteria. The irradiated drug and nonirradiated controls were analyzed by high-performance liquid chromatography (HPLC) for disulfiram and its major degradation product, diethyldithiocarbamate (DDC). Ultraviolet absorption spectra of irradiated and nonirradiated disulfiram were obtained. No organisms grew in any of the culture media. HPLC analysis indicated that disulfiram content of the irradiated specimens was not reduced, and DDC was not detected. There were no important differences between the ultraviolet spectra of the irradiated and nonirradiated samples. Disulfiram can be sterilized by gamma irradiation without chemical degradation.

  19. Applicability of the Sunna dosimeter for food irradiation control

    NASA Astrophysics Data System (ADS)

    Kovács, A.; Baranyai, M.; Wojnárovits, L.; Miller, S.; Murphy, M.; McLaughlin, W. L.; Slezsák, I.; Kovács, A. I.

    2002-03-01

    The quick development concerning the commercial application of food irradiation in the USA recently resulted in growing marketing of irradiated red meat as well as irradiated fresh and dried fruits. These gamma and electron irradiation technologies require specific dosimetry systems for process control. The new version of the Sunna dosimeter has been characterized in gamma, electron and bremsstrahlung radiation fields by measuring the optically stimulated luminescence (osl) at 530 nm both below and above 1 kGy, i.e. for disinfestation and for meat irradiation purposes. No humidity and no significant dose rate effect on the green osl signal was observed. The temperature coefficient was determined from 0°C up to about 40°C and to stabilize the osl signal after irradiation a heat treatment method was introduced. Based on these investigations the Sunna 'gamma' film is a suitable candidate for dose control below and above 1 kGy for food irradiation technologies.

  20. Stability of an injectable disulfiram formulation sterilized by gamma irradiation.

    PubMed

    Phillips, M; Agarwal, R P; Brodeur, R J; Garagusi, V F; Mossman, K L

    1985-02-01

    Stability of an injectable disulfiram suspension sterilized by gamma(gamma) irradiation was tested. Single doses of disulfiram powder in plastic syringes were subjected to 50,000 rads of gamma radiation. Culture media were inoculated with the irradiated drug to test for growth of bacteria, fungi, and mycobacteria. The irradiated drug and nonirradiated controls were analyzed by high-performance liquid chromatography (HPLC) for disulfiram and its major degradation product, diethyldithiocarbamate (DDC). Ultraviolet absorption spectra of irradiated and nonirradiated disulfiram were obtained. No organisms grew in any of the culture media. HPLC analysis indicated that disulfiram content of the irradiated specimens was not reduced, and DDC was not detected. There were no important differences between the ultraviolet spectra of the irradiated and nonirradiated samples. Disulfiram can be sterilized by gamma irradiation without chemical degradation. PMID:2983546

  1. Identification of gamma-irradiated papaya, melon and watermelon

    NASA Astrophysics Data System (ADS)

    Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

    2004-09-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  2. Prospects for Irradiation in Cellulosic Ethanol Production

    PubMed Central

    Saini, Anita; Aggarwal, Neeraj K.; Sharma, Anuja; Yadav, Anita

    2015-01-01

    Second generation bioethanol production technology relies on lignocellulosic biomass composed of hemicelluloses, celluloses, and lignin components. Cellulose and hemicellulose are sources of fermentable sugars. But the structural characteristics of lignocelluloses pose hindrance to the conversion of these sugar polysaccharides into ethanol. The process of ethanol production, therefore, involves an expensive and energy intensive step of pretreatment, which reduces the recalcitrance of lignocellulose and makes feedstock more susceptible to saccharification. Various physical, chemical, biological, or combined methods are employed to pretreat lignocelluloses. Irradiation is one of the common and promising physical methods of pretreatment, which involves ultrasonic waves, microwaves, γ-rays, and electron beam. Irradiation is also known to enhance the effect of saccharification. This review explains the role of different radiations in the production of cellulosic ethanol. PMID:26839707

  3. Membrane Protein Crystallization Using Laser Irradiation

    NASA Astrophysics Data System (ADS)

    Adachi, Hiroaki; Murakami, Satoshi; Niino, Ai; Matsumura, Hiroyoshi; Takano, Kazufumi; Inoue, Tsuyoshi; Mori, Yusuke; Yamaguchi, Akihito; Sasaki, Takatomo

    2004-10-01

    We demonstrate the crystallization of a membrane protein using femtosecond laser irradiation. This method, which we call the laser irradiated growth technique (LIGHT), is useful for producing AcrB crystals in a solution of low supersaturation range. LIGHT is characterized by reduced nucleation times. This feature is important for crystallizing membrane proteins because of their labile properties when solubilized as protein-detergent micelles. Using LIGHT, high-quality crystals of a membrane transporter protein, AcrB, were obtained. The resulting crystals were found to be of sufficiently high resolution for X-ray diffraction. The results reported here indicate that LIGHT is a powerful tool for membrane protein crystallization, as well as for the growth of soluble proteins.

  4. Precipitation during irradiation: an experimental example

    SciTech Connect

    Gelles, D.S.

    1981-01-01

    Neutron damage can significantly alter the process of precipitation from supersaturated solid solution. This is demonstrated by a series of experiments using a precipitation strengthened superalloy, Nimonic PE16 irradiated with fast neutrons over the temperature 400 to 650/sup 0/C. In disagreement with earlier predictions, precipitate development is found to be controlled by the competing processes of Ostwald coarsening and solute segregation due to drag by point defects to point defect sinks. Analysis of the kinetics of Ostwald coarsening reveals significant enhancement of diffusion rates due to irradiation in agreement with predictions and involving an activation energy on the order of one quarter that of thermal diffusion. Unusual precipitate morphologies were observed such as void shells, linear precipitate arrays and Archimedes' screw configurations. However, predicted temperature dependencies for solute segregation are not obeyed. An explanation is presented involving the coupling of the Ostwald coarsening mechanism with the solute segregation process.

  5. Precipitation during irradiation: an experimental example

    SciTech Connect

    Gelles, D.S.

    1981-01-01

    Neutron damage can significantly alter the process of precipitation from supersaturated solid solution. This is demonstrated by a series of experiments using a precipitation strengthened superalloy, Nimonic PE16 irradiated with fast neutrons over the temperature 400 to 650/sup 0/C. In disagreement with earlier predictions, precipitate development is found to be controlled by the competing processes of Ostwald coarsening and solute segregation due to drag by point defects to point defect sinks. Analysis of the kinetics of Ostwald coarsening reveals significant enhancement of diffusion rates due to irradiation in agreement with predictions and involving an activation energy on the order of one quarter that of thermal diffusion. Unusual precipitate morphologies were observed such as void shells, linear precipitate arrays and Archimedes' screw configurations. However, predicted temperature dependencies for solute segregation are not obeyed.

  6. Solar Irradiance, Plage and SOHO UV Images

    NASA Astrophysics Data System (ADS)

    Lopresto, James C.; Manross, Kevin

    1996-05-01

    Calcium K and H alpha plage and sunspot area have been monitored using Big Bear Observatory images on the INTERNET since November of 1992. The purpose of the project is to determine the correlation of changing plage area and solar irradiance changes. We also monitor changes in the K2 spec- tral index provided daily from Sacramento Peak. With the recent launching of the SOHO satellite, we are able to monitor the plage in the He II 304 Angstroms UV image. This image is near the top of the chromosphere nar or just under the transition region. The images show limb brightening as expected. Since it is widely believed that short time scale changes in the UV may be the dominant cause for low amplitude solar irradiance changes, the comparison of the "plage" ara in these UV images to those in conventional visible images should prove instructive.

  7. Laryngeal acinic cell carcinoma following thyroid irradiation

    SciTech Connect

    Reibel, J.F.; McLean, W.C.; Cantrell, R.W.

    1981-01-01

    Only three examples of acinic cell carcinoma of the larynx or trachea are found in the recent literature. A case of acinic cell carcinoma of the subglottic larynx and trachea was diagnosed and treated at the University of Virginia Medical Center. To our knowledge this is the first such case with a prior history of radiation to the neck. The patient is a 56-year-old woman who was irradiated for hyperthyroidism 46 years ago. When seen she also had parathyroid hyperplasia and multiple thyroid adenomas, conditions that frequently follow irradiation of the thyroid in children. These findings in this case support the concept that radiation may be responsible for inducing this tumor, which otherwise rarely occurs in this location. The use of electron microscopy was extremely useful in the diagnosis of this tumor. She was treated with total laryngectomy and right neck dissection and is now free of disease one year after surgery.

  8. Cadmium Nanowire Formation Induced by Ion Irradiation

    SciTech Connect

    Jiang, Weilin; Weber, William J.; Wang, Chong M.; Young, James S.; Boatner, Lynn A.; Lian, Jie; Wang, Lumin; Ewing, Rodney C.

    2005-07-04

    One-dimensional nanostructures, such as nanowires, of semiconductors and metals are of great technological interest due to their potential for many advanced technology applications. Utilization of these materials versus their bulk counterparts will not only allow for device miniaturisation, but also may improve device performance or create new functions. Here we report a novel method for the synthesis of crystalline Cd-nanowires without involving either templates or a “seeded” structure. Ion irradiation at low temperatures (≤ 295 K) has been used to induce material decomposition and phase segregation in a cadmium niobate pyrochlore (Cd2Nb2O7) wafer. During the formation and rupture of the gas-filled blisters in the material, soft metallic Cd is extruded/extracted as nanowires through pores in the exfoliated layer. The entire process may be readily controlled by changing the ion irradiation conditions (e.g., ion species, dose and energy) with minimal thermal constraints.

  9. Fall 2010 Total Solar Irradiance Calibration Workshop

    NASA Astrophysics Data System (ADS)

    Morrill, J. S.; Socker, D. G.; Willson, R. C.; Kopp, G.

    2010-12-01

    As part of a NASA-Sponsored program to understand the differences in Total Solar Irradiance (TSI) results reported by various space-based radiometers, the Naval Research Laboratory is hosting a Total Solar Irradiance Calibration Workshop. This workshop is a follow-on meeting to a similar workshop hosted by the National Institute for Standards and Technology in 2005. These workshops have been attended by many of the PI teams of the past and current TSI measuring instruments. The discussions at these workshops have addressed calibration methods and the numerous instrumental differences that need to be understood in order to bring the complete ensemble of results onto a common scale. In this talk we will present an overview of the NRL Calibration Workshop which will include results of recent calibration studies at various laboratories and have involved several TSI instruments.

  10. Neutron irradiation induced amorphization of silicon carbide

    SciTech Connect

    Snead, L.L.; Hay, J.C.

    1998-09-01

    This paper provides the first known observation of silicon carbide fully amorphized under neutron irradiation. Both high purity single crystal hcp and high purity, highly faulted (cubic) chemically vapor deposited (CVD) SiC were irradiated at approximately 60 C to a total fast neutron fluence of 2.6 {times} 10{sup 25} n/m{sup 2}. Amorphization was seen in both materials, as evidenced by TEM, electron diffraction, and x-ray diffraction techniques. Physical properties for the amorphized single crystal material are reported including large changes in density ({minus}10.8%), elastic modulus as measured using a nanoindentation technique ({minus}45%), hardness as measured by nanoindentation ({minus}45%), and standard Vickers hardness ({minus}24%). Similar property changes are observed for the critical temperature for amorphization at this neutron dose and flux, above which amorphization is not possible, is estimated to be greater than 130 C.

  11. UVA system for human cornea irradiation

    NASA Astrophysics Data System (ADS)

    Pereira, Fernando R. A.; Stefani, Mario; Otoboni, José A.; Richter, Eduardo H.; Rossi, Giuliano; Mota, Alessandro D.; Ventura, Liliane

    2009-02-01

    According to recent studies, an increase in corneal stiffness is a promising alternative for avoiding ectasias and for stagnating keratoconus of grades 1 and 2. The clinical treatment consists essentially of instilling Riboflavin (vitamin B2), in the cornea and then irradiating the corneal tissue, with UVA (365nm) radiation at 3mW/cm2 for 30min. This procedure provides collagen cross-linking in the corneal surface, increasing its stiffness. This work presents a system for UVA irradiation of the corneas at a peak wavelength of 365nm with adjustable power up to 5mW. The system has closed loop electronics to control the emitted power with 20% precision from the sated power output. The system is a prototype for performing corneal cross-linking and has been clinically tested. The closed loop electronics is a differential from the equipments available on the market.

  12. Sublethal irradiation promotes invasiveness of neuroblastoma cells

    SciTech Connect

    Schweigerer, Lothar; Rave-Fraenk, Margret; Schmidberger, Heinz; Hecht, Monica . E-mail: monica.hecht@med.uni-goettingen.de

    2005-05-13

    Neuroblastoma is the most frequent extracranial solid tumour of childhood. Despite multiple clinical efforts, clinical outcome has remained poor. Neuroblastoma is considered to be radiosensitive, but some clinical studies including the German trial NB90 failed to show a clinical benefit of radiation therapy. The mechanisms underlying this apparent discrepancy are still unclear. We have therefore investigated the effects of radiation on neuroblastoma cell behaviour in vitro. We show that sublethal doses of irradiation up-regulated the expression of the hepatocyte growth factor (HGF) and its receptor c-Met in some neuroblastoma cell lines. The increase in HGF/c-Met expression was correlated with enhanced invasiveness and activation of proteases degrading the extracellular matrix. Thus, irradiation at sublethal doses may promote the metastatic dissemination of neuroblastoma cells through activating the HGF/c-Met pathway and triggering matrix degradation.

  13. Forward and reverse characteristics of irradiated MOSFETs

    SciTech Connect

    Paccagnella, A.; Ceschia, M.; Verzellesi, G.; Dalla Betta, G.F.; Soncini, G.; Bellutti, P.; Fuochi, P.G.

    1996-06-01

    pMOSFETs biased with V{sub gs} < V{sub gd} during Co{sup 60} {gamma} irradiation have shown substantial differences between the forward and reverse subthreshold characteristics, induced by a non-uniform charge distribution in the gate oxide. Correspondingly, modest differences have been observed in the over-threshold I-V characteristics. After irradiation, the forward subthreshold curves can shift at higher or lower gate voltages than the reverse ones. The former behavior has been observed in long-channel devices, in agreement with the classical MOS theory and numerical simulations. The latter result has been obtained in short-channel devices, and it has been correlated to a parasitic punch-through conduction mechanism.

  14. Laser Assisted Cancer Immunotherapy: Surface Irradiation

    NASA Astrophysics Data System (ADS)

    Wilson, Joshua; Chen, Hsin-Wei; Bandyopadhyay, Pradip

    2006-03-01

    Experiments in our laboratory incorporate a non-invasive approach to treat superficial tumors in animal models. Based on the concept of Laser Assisted Cancer Immunotherapy, surface irradiation provides good information to compare to invasive alternatives. The procedure involves injecting an immunoadjuvant (Glycated Chitosan) as well as a light absorbing dye (Indocyanine Green) directly into the tumor (5 to 7 mm in diameter). The temperature of the tumor is raised using an infrared diode laser operating at 804 nm, with a silica fiber tip placed a set distance away from the surface of the tumor. We monitor the surface temperature using non-invasive (infrared detector probe) as well as the internal temperature of the tumor using invasive (micro thermocouples) methods. This study aims at the success of the surface irradiation mode to treat solid tumors. * This work is supported by a grant from The National Institute of Health.

  15. TEM study of neutron-irradiated iron

    SciTech Connect

    Horton, L.L.; Bentley, J.; Farrell, K.

    1981-01-01

    Results of a transmission electron microscopy study of the defect structure in iron neutron-irradiated to low fluences (less than or equal to 1 dpa) at temperatures of 455 to 1013/sup 0/K are presented. The dislocation microstructures coarsen with increasing irradiation temperature from decorated dislocations, through clusters of dislocation loops, to near-edge, interstitial dislocation loops with b = a<100>, and network segments. Significant cavity formation occurred only at 548 to 723/sup 0/K, with homogeneous distributions found only at 623 and 673/sup 0/K. The maximum swelling of 0.07% occurred at 673/sup 0/K. Large cavities had a truncated octahedral shape with (111) facets and (100) truncations. Damage halos were observed around boron-containing precipitates. The effects of interstitial impurities on microstructural development and the differences in the observed microstructures compared to those in refractory bcc metals are discussed. 8 figures, 6 tables.

  16. Stored energy in irradiated silicon carbide

    SciTech Connect

    Snead, L.L.; Burchell, T.D.

    1997-04-01

    This report presents a short review of the phenomenon of Wigner stored energy release from irradiated graphite and discusses it in relation to neutron irradiation of silicon carbide. A single published work in the area of stored energy release in SiC is reviewed and the results are discussed. It appears from this previous work that because the combination of the comparatively high specific heat of SiC and distribution in activation energies for recombining defects, the stored energy release of SiC should only be a problem at temperatures lower than those considered for fusion devices. The conclusion of this preliminary review is that the stored energy release in SiC will not be sufficient to cause catastrophic heating in fusion reactor components, though further study would be desirable.

  17. Prospects for Irradiation in Cellulosic Ethanol Production.

    PubMed

    Saini, Anita; Aggarwal, Neeraj K; Sharma, Anuja; Yadav, Anita

    2015-01-01

    Second generation bioethanol production technology relies on lignocellulosic biomass composed of hemicelluloses, celluloses, and lignin components. Cellulose and hemicellulose are sources of fermentable sugars. But the structural characteristics of lignocelluloses pose hindrance to the conversion of these sugar polysaccharides into ethanol. The process of ethanol production, therefore, involves an expensive and energy intensive step of pretreatment, which reduces the recalcitrance of lignocellulose and makes feedstock more susceptible to saccharification. Various physical, chemical, biological, or combined methods are employed to pretreat lignocelluloses. Irradiation is one of the common and promising physical methods of pretreatment, which involves ultrasonic waves, microwaves, γ-rays, and electron beam. Irradiation is also known to enhance the effect of saccharification. This review explains the role of different radiations in the production of cellulosic ethanol. PMID:26839707

  18. Nanodot formation induced by femtosecond laser irradiation

    SciTech Connect

    Abere, M. J.; Kang, M.; Goldman, R. S.; Yalisove, S. M.; Chen, C.; Rittman, D. R.; Phillips, J. D.; Torralva, B.

    2014-10-20

    The femtosecond laser generation of ZnSe nanoscale features on ZnSe surfaces was studied. Irradiation with multiple exposures produces 10–100 nm agglomerations of nanocrystalline ZnSe while retaining the original single crystal structure of the underlying material. The structure of these nanodots was verified using a combination of scanning transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. The nanodots continue to grow hours after irradiation through a combination of bulk and surface diffusion. We suggest that in nanodot formation the result of ultrafast laser induced point defect formation is more than an order of magnitude below the ZnSe ultrafast melt threshold fluence. This unique mechanism of point defect injection will be discussed.

  19. Fractionated total body irradiation for metastatic neuroblastoma

    SciTech Connect

    Kun, L.E.; Casper, J.T.; Kline, R.W.; Piaskowski, V.D.

    1981-11-01

    Twelve patients over one year old with neuroblastoma (NBL) metastatic to bone and bone marrow entered a study of adjuvant low-dose, fractionated total body irradiation (TBI). Six children who achieved a ''complete clinical response'' following chemotherapy (cyclophosphamide and adriamycin) and surgical resection of the abdominal primary received TBI (10 rad/fraction to totals of 100-120 rad/10-12 fx/12-25 days). Two children received concurrent local irradiation for residual abdominal tumor. The intervals from cessation of chemotherapy to documented progression ranged from 2-16 months, not substatially different from patients receiving similar chemotherapy and surgery without TBI. Three additional children with progressive NBL received similar TBI (80-120 rad/8-12 fx) without objective response.

  20. Polyethylene welding by pulsed visible laser irradiation

    NASA Astrophysics Data System (ADS)

    Torrisi, L.; Caridi, F.; Visco, A. M.; Campo, N.

    2011-01-01

    Laser welding of plastics is a relatively new process that induces locally a fast polymer heating. For most applications, the process involves directing a pulsed beam of visible light at the weld joint by going through one of the two parts. This is commonly referred to as “through transmission visible laser welding”. In this technique, the monochromatic visible light source uses a power ns pulsed laser in order to irradiate the joint through one part and the light is absorbed in the vicinity of the other part. In order to evaluate the mechanical resistance of the welded joint, mass quadrupole spectrometry, surface profilometry, microscopy techniques and mechanical shear tests were employed. The welding effect was investigated as a function of the laser irradiation time, nature of the polyethylene materials and temperature.

  1. Titanium implants in irradiated dog mandibles

    SciTech Connect

    Schweiger, J.W. )

    1989-08-01

    The use of osseointegrated titanium implants has been a great benefit to selected cancer patients who otherwise would not be able to wear conventional and/or maxillofacial prostheses. Cognizant of the risk of osteoradionecrosis, we used an animal model to seek experimental evidence for successful osseointegration in bone irradiated to tumoricidal levels. Five healthy male beagle dogs received 60 gray to a previously edentulated and healed area of the right hemimandible. The left hemimandible was kept as a nonirradiated control. After 9 months, titanium implants were placed and allowed an additional 5 1/2 months to osseointegrate. At that time, block specimens were obtained, radiographed, photographed, and analyzed histologically. Although statistical significance cannot be attached to the results, osseointegration was achieved in half of the irradiated specimens.

  2. Exploiting geometrical irradiation possibilities in MRT application

    NASA Astrophysics Data System (ADS)

    Bräuer-Krisch, E.; Requardt, H.; Régnard, P.; Corde, S.; Siegbahn, E. A.; LeDuc, G.; Blattmann, H.; Laissue, J.; Bravin, A.

    2005-08-01

    Microbeam Radiation Therapy (MRT) has the potential to treat infantile brain tumors when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of X-rays but provides unusual resistance to radioneurotoxicity, presumably from the rapid migration of regenerative endothelial cells from dose "valleys" into dose "peaks", i.e., into directly irradiated micro-slices of tissues. We will present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumor area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumoricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumor in the paths of the arrays.

  3. New irradiation geometry for microbeam radiation therapy

    NASA Astrophysics Data System (ADS)

    Bräuer-Krisch, E.; Requardt, H.; Régnard, P.; Corde, S.; Siegbahn, E.; LeDuc, G.; Brochard, T.; Blattmann, H.; Laissue, J.; Bravin, A.

    2005-07-01

    Microbeam radiation therapy (MRT) has the potential to treat infantile brain tumours when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of x-rays but provides unusual resistance to radioneurotoxicity, presumably from the migration of endothelial cells from 'valleys' into 'peaks', i.e., into directly irradiated microslices of tissues. We present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumour area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumouricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumour in the paths of the arrays.

  4. Stress relaxation of vitreous silica on irradiation

    SciTech Connect

    Primak, W.

    1982-11-01

    The radiation-induced stress relaxation which is observed on ion bombardment of vitreous silica is described as a viscoelastic behavior in which the apparent viscosity is reduced to approx.10/sup 14/ Poise during irradiation and then increases rapidly by 4 or 5 orders of magnitude on cessation or interruption of irradiation. The bombarded layer appears to possess a viscosity approx.10/sup 19/ Poise, lower than would be expected for normal vitreous silica. On electron bombardment the viscosity is also reduced, but not as greatly as an ion bombardment, yet sufficiently to result in the whole radiation-induced volume contraction being realized perpendicularly to the surface, as has been found for ion bombardment. The maximum elastic stored energy which can be realized is but a fraction of a calorie per gram, hence the reported values of 200 cal/g would seem to be associated with the fragmentation of the network responsible for the reduced viscosity.

  5. Swift Heavy Ion Irradiation of Cobalt Nanoparticles

    NASA Astrophysics Data System (ADS)

    Sprouster, D. J.; Giulian, R.; Schnohr, C. S.; Kluth, P.; Araujo, L. L.; Byrne, A. P.; Foran, G. J.; Ridgway, M. C.

    2009-01-01

    It is well known that the electronic energy loss released by swift heavy ions can cause considerable atomic movement in various solids. Here, we present a study of the effects of swift heavy ion irradiation on Co nanoparticles embedded within a silica host matrix. The evolution of the Co nanoparticle crystal phase, structural properties, shape and size has been characterized using a combination of x-ray absorption spectroscopy and transmission electron microscopy. An FCC-to-HCP phase transformation is observed at low fluences, while higher fluences result in significant changes in the short range order and NP shape. After an incubation fluence the nanoparticles deform into ellipsoids, preferentially aligned parallel to the incident beam direction. The threshold diameter for elongation was comparable to the saturation value of the ellipsoid width. We correlate this saturation value with the diameter of the molten track induced in amorphous silica by swift heavy ion irradiation.

  6. Total lymphoid irradiation for multiple sclerosis

    SciTech Connect

    Devereux, C.K.; Vidaver, R.; Hafstein, M.P.; Zito, G.; Troiano, R.; Dowling, P.C.; Cook, S.D.

    1988-01-01

    Although chemical immunosuppression has been shown to benefit patients with chronic progressive multiple sclerosis (MS), it appears that chemotherapy has an appreciable oncogenic potential in patients with multiple sclerosis. Accordingly, we developed a modified total lymphoid irradiation (TLI) regimen designed to reduce toxicity and applied it to a randomized double blind trial of TLI or sham irradiation in MS. Standard TLI regimens were modified to reduce dose to 1,980 rad, lowering the superior mantle margin to midway between the thyroid cartilage and angle of the mandible (to avert xerostomia) and the lower margin of the mantle field to the inferior margin of L1 (to reduce gastrointestinal toxicity by dividing abdominal radiation between mantle and inverted Y), limiting spinal cord dose to 1,000 rad by custom-made spine blocks in the mantle and upper 2 cm of inverted Y fields, and also protecting the left kidney even if part of the spleen were shielded. Clinical efficacy was documented by the less frequent functional scale deterioration of 20 TLI treated patients with chronic progressive MS compared to to 20 sham-irradiated progressive MS patients after 12 months (16% versus 55%, p less than 0.03), 18 months (28% versus 63%, p less than 0.03), and 24 months (44% versus 74%, N.S.). Therapeutic benefit during 3 years follow-up was related to the reduction in lymphocyte count 3 months post-irradiation (p less than 0.02). Toxicity was generally mild and transient, with no instance of xerostomia, pericarditis, herpes zoster, or need to terminate treatment in TLI patients. However, menopause was induced in 2 patients and staphylococcal pneumonia in one.

  7. Electron irradiation of tandem junction solar cells

    NASA Technical Reports Server (NTRS)

    Anspaugh, B. E.; Miyahira, T. F.; Scott-Monck, J. A.

    1979-01-01

    The electrical behavior of 100 micron thick tandem junction solar cells manufactured by Texas Instruments was studied as a function of 1 MeV electron fluence, photon irradiation, and 60 C annealing. These cells are found to degrade rapidly with radiation, the most serious loss occurring in the blue end of the cell's spectral response. No photon degradation was found to occur, but the cells did anneal a small amount at 60 C.

  8. Rotational Variability in Ultraviolet Solar Spectral Irradiance

    NASA Astrophysics Data System (ADS)

    Snow, M. A.; Richard, E. C.; Harder, J. W.; Thuillier, G. O.

    2011-12-01

    There are currently many observations and models of the Solar Spectral Irradiance (SSI) in the ultraviolet (UV). The models and the observations are often in agreement, but sometimes have significant differences. Using the decline of solar cycle 23 and the rise of solar cycle 24 as a test case, we will investigate the systematic differences between the short term SSI variation observed by satellite instruments and the predictions of proxy models.

  9. Histologic changes in previously irradiated thyroid glands

    SciTech Connect

    Valdiserri, R.O.; Borochovitz, D.

    1980-03-01

    Thyroid tissue from 90 patients with a history of therapeutic irradiation to the head and neck in childhood and adolescence was examined microscopically. In addition to the well-known observation that these individuals have an increased incidence of primary thyroid carcinoma, it was also demonstrated that they have an increased incidence of benign histologic changes. These changes represent a spectrum from nonspecific hyperplastic lesions to benign neoplasis and thyroidltis.

  10. Metal fuel manufacturing and irradiation performance

    SciTech Connect

    Pedersen, D.R.; Walters, L.C.

    1992-01-01

    The advances in metal fuel by the Integral Fast Reactor Program at Argonne National Laboratory are the subject of this paper. The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The advances stressed in the paper include fuel irradiation performance, and improved passive safety. The goals and the safety philosophy of the Integral Fast Reactor Program are stressed.

  11. Metal fuel manufacturing and irradiation performance

    SciTech Connect

    Pedersen, D.R.; Walters, L.C.

    1992-06-01

    The advances in metal fuel by the Integral Fast Reactor Program at Argonne National Laboratory are the subject of this paper. The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The advances stressed in the paper include fuel irradiation performance, and improved passive safety. The goals and the safety philosophy of the Integral Fast Reactor Program are stressed.

  12. Optical Properties of Irradiated Topaz Crystals

    NASA Astrophysics Data System (ADS)

    Skvortsova, V.; Mironova-Ulmane, N.; Trinkler, L.

    2015-04-01

    The results of an investigation of UV-Visible absorption and photoluminescence spectra of colorless topaz before and after neutron irradiation, natural blue topaz from Ukraine, and yellow topaz are presented. We assume that the absorption band ∼ 620 nm and broad emission band 300-700 nm in topaz crystals are associated with exchange interaction between a radiation defect (anion vacancies, which capture one or two electrons) and impurity ions Cr3+, Fe3+ and Mn2+.

  13. Percutaneous needle biopsy of the irradiated skeleton

    SciTech Connect

    Edeiken, B.; deSantos, L.A.

    1983-03-01

    Percutaneous needle biopsy was performed in 20 patients who had radiologic abnormalities after irradiation of the skeleton. The biopsies were performed to determine the nature of the bone changes and to differentiate radiation necrosis from metastases or local tumor extension. Eleven patients had tumors, two of which were radiation-induced sarcomas; nine patients did not show evidence of tumor. One patient had osteomyelitis rather than the suspected tumor. The value of percutaneous needle biopsy in the postirradiated skeleton is discussed.

  14. Modeled soft X-ray solar irradiances

    NASA Technical Reports Server (NTRS)

    Tobiska, W. Kent

    1994-01-01

    Solar soft X-rays have historically been inaccurately modeled in both relative variations and absolute magnitudes by empirical solar extreme ultraviolet (EUV) irradiance models. This is a result of the use of a limited number of rocket data sets which were primarily associated with the calibration of the AE-E satellite EUV data set. In this work, the EUV91 solar EUV irradiance model has been upgraded to improve the accuracy of the 3.0 to 5.0 nm relative irradiance variations. The absolute magnitude estimate of the flux in this wavelength range has also been revised upwards. The upgrade was accomplished by first digitizing the SOLRAD 11 satellite 4.4 to 6.0 nm measured energy flux data set, then extracting and extrapolating a derived 3.0 to 5.0 nm photon flux from these data, and finally by performing a correlation between these derived data and the daily and 81-day mean 10.7 cm radio flux emission using a multiple linear regression technique. A correlation coefficient of greater than 0.9 was obtained between the dependent and independent data sets. The derived and modeled 3.0 to 5.0 nm flux varies by more than an order of magnitude over a solar cycle, ranging from a flux below 1 x 10(exp 8) to a flux greater than 1 x 10(exp 9) photons per sq cm per sec. Solar rotational (27-day) variations in the flux magnitude are a factor of 2. The derived and modeled irradiance absolute values are an order of magnitude greater than previous values from rocket data sets related to the calibration of the AE-E satellite.

  15. Antitumor Immunity Induced after α Irradiation123

    PubMed Central

    Gorin, Jean-Baptiste; Ménager, Jérémie; Gouard, Sébastien; Maurel, Catherine; Guilloux, Yannick; Faivre-Chauvet, Alain; Morgenstern, Alfred; Bruchertseifer, Frank; Chérel, Michel; Davodeau, François; Gaschet, Joëlle

    2014-01-01

    Radioimmunotherapy (RIT) is a therapeutic modality that allows delivering of ionizing radiation directly to targeted cancer cells. Conventional RIT uses β-emitting radioisotopes, but recently, a growing interest has emerged for the clinical development of α particles. α emitters are ideal for killing isolated or small clusters of tumor cells, thanks to their specific characteristics (high linear energy transfer and short path in the tissue), and their effect is less dependent on dose rate, tissue oxygenation, or cell cycle status than γ and X rays. Several studies have been performed to describe α emitter radiobiology and cell death mechanisms induced after α irradiation. But so far, no investigation has been undertaken to analyze the impact of α particles on the immune system, when several studies have shown that external irradiation, using γ and X rays, can foster an antitumor immune response. Therefore, we decided to evaluate the immunogenicity of murine adenocarcinoma MC-38 after bismuth-213 (213Bi) irradiation using a vaccination approach. In vivo studies performed in immunocompetent C57Bl/6 mice induced a protective antitumor response that is mediated by tumor-specific T cells. The molecular mechanisms potentially involved in the activation of adaptative immunity were also investigated by in vitro studies. We observed that 213Bi-treated MC-38 cells release “danger signals” and activate dendritic cells. Our results demonstrate that α irradiation can stimulate adaptive immunity, elicits an efficient antitumor protection, and therefore is an immunogenic cell death inducer, which provides an attractive complement to its direct cytolytic effect on tumor cells. PMID:24862758

  16. Irradiation effects on polymer-model compounds

    NASA Astrophysics Data System (ADS)

    Seguchi, Tadao; Katsumura, Yosuke; Hayashi, Nariyuki; Hayakawa, Naohiro; Tamura, Naoyuki; Tabata, Yoneho

    Irradiation effects on n-paraffins and squalane, used as models of polymers, were investigated by product analysis. Four n-paraffins, C 20H 42, C 21H 44, C 23H 48 and C 24H 50, and squalane (C 30H 62) were γ-irradiated under vacuum in liquid, crystalline and glassy states. The evolved gases were analyzed by gas chromatography and changes in molecular weight were analyzed by liquid chromatography and mass spectroscopy. G-values for crosslinking of n-paraffins were 1.2 for crystalline states (at 25°C) and 1.7 for liquid states (at 55°C), and showed no difference between odd and even carbon numbers. The G-value of liquid squalane was 1.7; it was 1.3 for the glassy state at low temperature (-77°C). Double bonds were common in the crosslinked products, especially after liquid-phase irradiation. The probability of chain scission was estimated as being negligible, though a small number of chain-scission products (which were products of scission at chain-ends or side chains) were observed by gas analysis.

  17. Hydrogen retention in ion irradiated steels

    SciTech Connect

    Hunn, J.D.; Lewis, M.B.; Lee, E.H.

    1998-11-01

    In the future 1--5 MW Spallation Neutron Source, target radiation damage will be accompanied by high levels of hydrogen and helium transmutation products. The authors have recently carried out investigations using simultaneous Fe/He,H multiple-ion implantations into 316 LN stainless steel between 50 and 350 C to simulate the type of radiation damage expected in spallation neutron sources. Hydrogen and helium were injected at appropriate energy and rate, while displacement damage was introduced by nuclear stopping of 3.5 MeV Fe{sup +}, 1 {micro}m below the surface. Nanoindentation measurements showed a cumulative increase in hardness as a result of hydrogen and helium injection over and above the hardness increase due to the displacement damage alone. TEM investigation indicated the presence of small bubbles of the injected gases in the irradiated area. In the current experiment, the retention of hydrogen in irradiated steel was studied in order to better understand its contribution to the observed hardening. To achieve this, the deuterium isotope ({sup 2}H) was injected in place of natural hydrogen ({sup 1}H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with {sup 3}He. Results showed a surprisingly high concentration of deuterium to be retained in the irradiated steel at low temperature, especially in the presence of helium. There is indication that hydrogen retention at spallation neutron source relevant target temperatures may reach as high as 10%.

  18. Industrial irradiator radiation safety program assessments

    NASA Astrophysics Data System (ADS)

    Smith, Mark A.

    2000-03-01

    Considerable attention is typically given to radiation safety in the design of irradiators and initially establishing the program. However, one component that may not receive enough attention is applying the continuous improvement philosophy to the radiation safety program. Periodic total program assessments of radiation safety can ensure that the design and implementation of the program continues to be applicable to the operations. The first step in the process must be to determine what is to be covered in the program assessment. While regulatory compliance audits are a component, the most useful evaluation will extend beyond looking only at compliance and determine whether the radiation safety program is the most appropriate for the particular operation. Several aspects of the irradiator operation, not all of which may routinely be considered "radiation safety", per se, should be included: Design aspects of the irradiator and operating system, system controls, and maintenance procedures, as well as the more traditional radiation safety program components such as surveys, measurements and training.

  19. Total scalp irradiation using helical tomotherapy

    SciTech Connect

    Orton, Nigel . E-mail: nporton@facstaff.wisc.edu; Jaradat, Hazim; Welsh, James; Tome, Wolfgang

    2005-09-30

    Homogeneous irradiation of the scalp poses technical and dosimetric challenges due to the extensive, superficial, curved treatment volume. Conventional treatments on a linear accelerator use multiple matched electron fields or a combination of electron and photon fields. Problems with these techniques include dose heterogeneity in the target due to varying source-to-skin distance (SSD) and angle of beam incidence, significant dose to the brain, and the potential for overdose or underdose at match lines between the fields. Linac-based intensity-modulated radiation therapy (IMRT) plans have similar problems. This work presents treatment plans for total scalp irradiation on a helical tomotherapy machine. Helical tomotherapy is well-suited for scalp irradiation because it has the ability to deliver beamlets that are tangential to the scalp at all points. Helical tomotherapy also avoids problems associated with field matching and use of more than one modality. Tomotherapy treatment plans were generated and are compared to plans for treatment of the same patient on a linac. The resulting tomotherapy plans show more homogeneous target dose and improved critical structure dose when compared to state-of-the-art linac techniques. Target equivalent uniform dose (EUD) for the best tomotherapy plan was slightly higher than for the linac plan, while the volume of brain tissue receiving over 30 Gy was reduced by two thirds. Furthermore, the tomotherapy plan can be more reliably delivered than linac treatments, because the patient is aligned prior to each treatment based on megavoltage computed tomography (MVCT)

  20. Irradiation response and stability of nanoporous materials

    SciTech Connect

    Fu, Engang; Wang, Yongqiang; Serrano De Caro, Magdalena; Caro, Jose A.; Zepeda-Ruiz, L; Bringa, E.; Nastasi, Mike; Baldwin, Jon K.

    2012-08-28

    Nanoporous materials consist of a regular organic or inorganic framework supporting a regular, porous structure. Pores are by definition roughly in the nanometre range, that is between 0.2 nm and 100 nm. Nanoporous materials can be subdivided into 3 categories (IUPAC): (1) Microporous materials - 0.2-2 nm; (2) Mesoporous materials - 2-50 nm; and (3) Macroporous materials - 50-1000 nm. np-Au foams were successfully synthesized by de-alloying process. np-Au foams remain porous structure after Ne ion irradiation to 1 dpa. Stacking Fault Tetrahedra (SFTs) were observed in RT irradiated np-Au foams under the highest and intermediate fluxes, but not under the lowest flux. SFTs were not observed in LNT irradiated np-Au foams under all fluxes. The vacancy diffusivity in Au at RT is high enough so that the vacancies have enough time to agglomerate and then collapse to form SFTs. The high ion flux creates more damage per unit time; vacancies don't have enough time to diffuse or recombine. As a result, SFTs were formed at high ion fluxes.

  1. Electron beam irradiation of fluoropolymers containing polyethers

    NASA Astrophysics Data System (ADS)

    Bucio, E.; Burillo, G.; Tapia, F.; Adem, E.; Cedillo, G.; Cassidy, P. E.

    2009-02-01

    A highly fluorinated monomer, 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenyl methoxy-2-propyl)benzene (12F-FBE) was polymerized with some diphenols by polycondensation and then was electron beam irradiated between 100 and 1000 kGy to determine degradation radiochemistry yield ( Gs) by gel permeation chromatography (GPC). The samples were characterized after irradiation by DSC, FTIR, and nuclear magnetic resonance (NMR). The fluoropolymers show apparent degradation in mechanical properties at 300 kGy, except 12F-FBE polymerized with biphenol and bisphenol A, when they did not show any apparent physical change up to 300 kGy; and continue to be flexible and transparent, with a radiochemical yield scission ( Gs) of 0.75, 0.53, 0.88, and 0.38 for 12F-FBE/SDL aliphatic, 12F-FBE/biphenol, 12F-FBE/bisphenol A, and 12F-FBE/bisphenol O, respectively. The number average molecular weights for three of the polymers decrease upon 1000 kGy irradiation to 10% of their original values; however, the polymer from bisphenol A is much more stable and its Mn decreases to only 24% of original.

  2. Nitride fuels irradiation performance data base

    SciTech Connect

    Brozak, D.E.; Thomas, J.K.; Peddicord, K.L.

    1987-01-01

    An irradiation performance data base for nitride fuels has been developed from an extensive literature search and review that emphasized uranium nitride, but also included performance data for mixed nitrides ((U,Pu)N) and carbonitrides ((U,Pu)C,N) to increase the quantity and depth of pin data available. This work represents a very extensive effort to systematically collect and organize irradiation data for nitride-based fuels. The data base has many potential applications. First, it can facilitate parametric studies of nitride-based fuels to be performed using a wide range of pin designs and operating conditions. This should aid in the identification of important parameters and design requirements for multimegawatt and SP-100 fuel systems. Secondly, the data base can be used to evaluate fuel performance models. For detailed studies, it can serve as a guide to selecting a small group of pin specimens for extensive characterization. Finally, the data base will serve as an easily accessible and expandable source of irradiation performance information for nitride fuels.

  3. Upgrade to the Birmingham Irradiation Facility

    NASA Astrophysics Data System (ADS)

    Dervan, P.; French, R.; Hodgson, P.; Marin-Reyes, H.; Parker, K.; Wilson, J.; Baca, M.

    2015-10-01

    The Birmingham Irradiation Facility was developed in 2013 at the University of Birmingham using the Medical Physics MC40 cyclotron. It can achieve High Luminosity LHC (HL-LHC) fluences of 1015 (1 MeV neutron equivalent (neq)) cm-2 in 80 s with proton beam currents of 1 μA and so can evaluate effectively the performance and durability of detector technologies and new components to be used for the HL-LHC. Irradiations of silicon sensors and passive materials can be carried out in a temperature controlled cold box which moves continuously through the homogenous beamspot. This movement is provided by a pre-configured XY-axis Cartesian robot scanning system. In 2014 the cooling system and cold box were upgraded from a recirculating glycol chiller system to a liquid nitrogen evaporative system. The new cooling system achieves a stable temperature of -50 °C in 30 min and aims to maintain sub-0 °C temperatures on the sensors during irradiations. This paper reviews the design, development, commissioning and performance of the new cooling system.

  4. Irradiation Products On Dwarf Planet Makemake

    NASA Astrophysics Data System (ADS)

    Brown, M. E.; Schaller, E. L.; Blake, G. A.

    2015-03-01

    The dark, reddish tinged surfaces of icy bodies in the outer solar system are usually attributed to the long term irradiation of simple hydrocarbons leading to the breaking of C-H bonds, loss of hydrogen, and the production of long carbon chains. While the simple hydrocarbon methane is stable and detected on the most massive bodies in the Kuiper Belt, evidence of active irradiation chemistry is scant except for the presence of ethane on methane-rich Makemake and the possible detections of ethane on more methane-poor Pluto and Quaoar. We have obtained deep high signal-to-noise spectra of Makemake from 1.4 to 2.5 μm in an attempt to trace the radiation chemistry in the outer solar system beyond the initial ethane formation. We present the first astrophysical detection of solid ethylene and evidence for acetylene and high-mass alkanes—all expected products of the continued irradiation of methane, and use these species to map the chemical pathway from methane to long-chain hydrocarbons.

  5. Dosimetry of biological irradiations using radiochromic films

    NASA Astrophysics Data System (ADS)

    Aldelaijan, S.; Nobah, A.; Alsbeih, G.; Moftah, B.; Aldahlawi, I.; Alzahrany, A.; Tomic, N.; Devic, S.

    2013-05-01

    Delivering accurate radiation dose to blood specimens during biological irradiations is essential in quantifying damage of ionizing radiation. To estimate dose to blood samples as accurately as possible, pieces of EBT2 model GAFCHROMIC™ film were placed within an approximately 10 mm finely ground rice layer that was used to simulate test specimens inside 40 mL plastic flasks. Irradiations of flasks were carried out using an X-RAD 320 irradiator with a beam quality of 320 kVp and a measured half value layer of 1.12 mm Cu, in air and in a full scattering setup which consisted of either rice or Solid Water™ (SW) surrounding flasks, filled to the same level at top of the flasks, together with a 5 cm thick SW slab beneath them. Outputs, per cent depth doses and beam profiles at different depths were measured and compared between setups. For the same setting, the dose delivered to the middle flask under the full scattering setup is 22% larger than with the in-air setup at the depth of the specimen and 9.2% more homogeneous across the specimen thickness of 10 mm (2.3% variation in comparison to the surface). Rice showed a fairly similar performance to SW within 1% at the same depth of 10 mm. Experimental setup based on full scattering conditions was shown to provide faster, more homogenous and fairly uniform dose delivery to biological specimens in comparison to conventionally used in-air setups.

  6. Evaporation of solids by pulsed laser irradiation

    NASA Astrophysics Data System (ADS)

    Stafast, H.; Von Przychowski, M.

    The focused beam of a KrF laser (248 nm) has been applied to irradiate targets of Al 2O 3, SiC, graphite, Pb, Ni, Cr, quartz, and NaCl at variable laser energy flux is the range 0-13 J/cm 2. The amount of target material ejected into the vacuum (background pressure about 8 × 10 -4 Torr) was determined from the target weight before and after laser irradiation. The average number of particles (formula weight) evaporated per laser pulse and per unit of irradiated target area is non-linearly dependent on the laser energy flux. The evaporation of Al 2O 3, SiC, and graphite is showing a well-defined flux threshold while the vaporization of Pb, Ni and Cr is rising smoothly with increasing flux. With both groups of materials laser evaporation is monotonically increasing with the laser energy flux. NaCl and quartz, on the other hand, are showing an intermediate maximum in the laser vaporization efficiency.

  7. Hodgkin's disease: thyroid dysfunction following external irradiation

    SciTech Connect

    Tamura, K.; Shimaoka, K.

    1981-01-01

    The thyroid gland is commonly included in the field of radiation therapy for patients with malignant lymphoma and with head and neck tumors. The radiation dose for malignant diseases varies considerably depending on the purpose of treatment and the institutional policies. A substantial number of these patients are developing subclinical and clinical hypothyroidism. The risk of developing hypothyroidism after a moderate radiation dose of 2000 to 4500 rads has been reported to be 10 to 20 percent. In addition, subclinical hypothyroidism is induced further in one third of the patients. There are also suggestions that external irradiation of the thyroid gland in patients with malignant lymphomas, as well as internal irradiation with radioiodine of the normal and hyperthyroid human thyroid glands, would induce elevations of serum antithyroid autoantibody titers. However, only a few cases of Graves disease following irradiation to the thyroid gland have been reported. We encountered a young woman who received radiation therapy to the mantle field for her Hodgkin's disease and developed hypothyroxinemia without overt signs and symptoms of hypothyroidism, followed by appearance of nodular goiter and then full-blown Graves disease.

  8. Blue LED irradiation to hydration of skin

    NASA Astrophysics Data System (ADS)

    Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

    2015-06-01

    Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

  9. Electron Irradiation of Interstellar Ice Analogues

    NASA Astrophysics Data System (ADS)

    Nair, B. G.; Mason, N. J.

    2011-05-01

    Molecular synthesis in the Universe primarily occurs in the icy mantles on dust grains in dense interstellar dust clouds. The interaction of photons, electrons and cosmic rays with these ice mantles triggers complex chemical synthesis leading to the formation of complex molecules. Such molecular reactions can only be understood by systematic laboratory studies. In our experiments astrophysical environments are recreated in the laboratory using an ultra high vacuum chamber (UHV) capable of reaching pressures of the order of 10 -10 mBar containing a liquid helium cryostat capable of attaining a temperature of 20 K. Ice films are deposited on a ZnSe substrate (cooled by cryostat) by background deposition and irradiated with electrons of 1KeV energy. Chemical changes induced by electron irradiation were monitored by an infrared spectrometer. By varying the temperature, we also investigate the temperature dependence on the kinetics of the reactions. In this poster we will present the first results of electron irradiation of simple organic molecules like formamide (HCONH2) and allyl alcohol (CH2CHCH2OH).

  10. Multivariate Analysis of Solar Spectral Irradiance Measurements

    NASA Technical Reports Server (NTRS)

    Pilewskie, P.; Rabbette, M.

    2001-01-01

    Principal component analysis is used to characterize approximately 7000 downwelling solar irradiance spectra retrieved at the Southern Great Plains site during an Atmospheric Radiation Measurement (ARM) shortwave intensive operating period. This analysis technique has proven to be very effective in reducing a large set of variables into a much smaller set of independent variables while retaining the information content. It is used to determine the minimum number of parameters necessary to characterize atmospheric spectral irradiance or the dimensionality of atmospheric variability. It was found that well over 99% of the spectral information was contained in the first six mutually orthogonal linear combinations of the observed variables (flux at various wavelengths). Rotation of the principal components was effective in separating various components by their independent physical influences. The majority of the variability in the downwelling solar irradiance (380-1000 nm) was explained by the following fundamental atmospheric parameters (in order of their importance): cloud scattering, water vapor absorption, molecular scattering, and ozone absorption. In contrast to what has been proposed as a resolution to a clear-sky absorption anomaly, no unexpected gaseous absorption signature was found in any of the significant components.

  11. ESR identification of gamma-irradiated albendazole

    NASA Astrophysics Data System (ADS)

    Çolak, Seyda

    2010-01-01

    The use of ionizing radiation for sterilization of pharmaceuticals is a well-established technology. In the present work, the spectroscopic and kinetic features of the radicals induced in gamma-irradiated solid albendazole samples is investigated at different temperatures in the dose range of 3-34 kGy by electron spin resonance (ESR) spectroscopy. Irradiation with gamma radiation produced two different radical species in albendazole. They were fairly stable at room temperature but relatively unstable above room temperature, giving rise to an unresolved ESR spectrum consisting of three resonance peaks centered at g=2.0057. Decay activation energies of the contributing radical species were calculated to be 47.8 (±13.5) and 50.5 (±9.7) kJ/mol using the signal intensity decay data derived from annealing studies performed at high temperatures. A linear function of the applied dose was found to best describe the experimental dose-response data. Albendazole does not present the characteristics of good dosimetric materials. However, the discrimination of irradiated albendazole from its unirradiated form was possible even 6 months after storage in normal conditions. Based on these findings, it is concluded that albendazole and albendazole-containing drugs can be safely sterilized by gamma radiation and that ESR spectroscopy could be successfully used as a potential technique for monitoring their radiosterilization.

  12. Protein Quality of Irradiated Brazilian Beans

    NASA Astrophysics Data System (ADS)

    Delincée, Henry; Villavicencio, Anna-Lucia C. H.; Mancini-Filho, Jorge

    1998-06-01

    Beans are a major source of dietary protein in Brazil. However, high losses due to insect infestation occur after each harvest. To combat these losses, radiation processing of beans offers promise as an alternative to chemical treatment, provided the nutritional quality of beans is not impaired by the radiation treatment. Conflicting results have been published about the effect of radiation on the biological value of legume proteins. Therefore, two varieties of Brazilian beans were studied: 1) Phaseolus vulgaris L., var. carioca and 2) Vigna unguiculata (L.) Walp, var. macaçar. The beans were irradiated with doses of 0, 0.5, 1.0, 2.5, 5.0 and 10 kGy. Since irradiated beans will be consumed after appropriate storage, the beans under study were stored for 6 months at ambient temperature. Protein quality was measured by a biological assay employing the nitrogen balance approach in weanling rats. The animals were fed with optimally cooked beans, which were the only source of protein (˜10%). Nitrogen contents of legumes, diets, animal urine and faeces were determined by Kjeldahl analysis. The indices for apparent protein quality: net protein utilisation, digestibility and biological value were not influenced by irradiation. Thus, radiation treatment of Brazilian beans offers considerable promise as an effective insect disinfection process, without impairing the biological quality of the valuable bean protein.

  13. Local brain heavy ion irradiation induced Immunosuppression

    NASA Astrophysics Data System (ADS)

    Lei, Runhong; Deng, Yulin; Huiyang Zhu, Bitlife.; Zhao, Tuo; Wang, Hailong; Yu, Yingqi; Ma, Hong; Wang, Xiao; Zhuang, Fengyuan; Qing, Hong

    Purpose: To investigate the long term effect of acute local brain heavy ion irradiation on the peripheral immune system in rat model. Methodology: Only the brain of adult male Wistar rats were radiated by heavy ions at the dose of 15 Gy. One, two and three months after irradiation, thymus and spleen were analyzed by four ways. Tunel assay was performed to evaluate the percentage of apoptotic cells in thymus and spleen, level of Inflammatory cytokines (IL-2, IL-6, SSAO, and TNF-α) was detected by ELISA assay, the differentiation of thymus T lymphocyte subsets were measured by flow cytometry and the relative expression levels of genes related to thymus immune cell development were measured by using quantitative real-time PCR. Results: Thymus and spleen showed significant atrophy from one month to three months after irradiation. A high level of apoptosis in thymus and spleen were obtained and the latter was more vulnerable, also, high level of inflammatory cytokines were found. Genes (c-kit, Rag1, Rag2 and Sca1) related to thymus lymphocytes’ development were down-regulated. Conclusion: Local area radiation in the rat brain would cause the immunosuppression, especially, the losing of cell-mediated immune functions. In this model, radiation caused inflammation and then induced apoptosis of cells in the immune organs, which contributed to immunosuppression.

  14. Irradiation Environment of the Materials Test Station

    SciTech Connect

    Pitcher, Eric John

    2012-06-21

    Conceptual design of the proposed Materials Test Station (MTS) at the Los Alamos Neutron Science Center (LANSCE) is now complete. The principal mission is the irradiation testing of advanced fuels and materials for fast-spectrum nuclear reactor applications. The neutron spectrum in the fuel irradiation region of MTS is sufficiently close to that of fast reactor that MTS can match the fast reactor fuel centerline temperature and temperature profile across a fuel pellet. This is an important characteristic since temperature and temperature gradients drive many phenomena related to fuel performance, such as phase stability, stoichiometry, and fission product transport. The MTS irradiation environment is also suitable in many respects for fusion materials testing. In particular, the rate of helium production relative to atomic displacements at the peak flux position in MTS matches well that of fusion reactor first wall. Nuclear transmutation of the elemental composition of the fusion alloy EUROFER97 in MTS is similar to that expected in the first wall of a fusion reactor.

  15. Solar Irradiance Data Products at the LASP Interactive Solar IRradiance Datacenter (LISIRD)

    NASA Astrophysics Data System (ADS)

    Ware Dewolfe, A.; Wilson, A.; Lindholm, D. M.; Pankratz, C. K.; Snow, M. A.; Woods, T. N.

    2010-12-01

    The Laboratory for Atmospheric and Space Physics (LASP) has developed the LASP Interactive Solar IRradiance Datacenter (LISIRD) to provide access to a comprehensive set of solar irradiance measurements. LISIRD has recently been updated to serve many new datasets and models, including data from SORCE, UARS-SOLSTICE, SME, and TIMED-SEE, and model data from the Flare Irradiance Spectral Model (FISM). The user interface emphasizes web-based interactive visualizations, allowing users to explore and compare this data before downloading it for analysis. The data provided covers a wavelength range from soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as wavelength-independent Total Solar Irradiance (TSI). Combined data from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments provide continuous coverage from 1981 to the present, while Lyman-alpha measurements, FISM daily data, and TSI models date from the 1940s to the present. LISIRD will also host Glory TSI data as part of the SORCE data system. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD’s interfaces.

  16. Solar spectral irradiance model validation using Solar Spectral Irradiance and Solar Radius measurements

    NASA Astrophysics Data System (ADS)

    Thuillier, Gérard; Zhu, Ping; Shapiro, Alexander; Sofia, Sabatino; Tagirov, Rinat; Van Ruymbeke, Michel; Schmutz, Werner

    2016-04-01

    The importance of the reliable solar spectral irradiance (SSI) data for solar and climate physics is now well acknowledged. In particular, the irradiance time series are necessary for most of the current studies concerning climate evolution. However, space instruments are vulnerable to the degradation due to the environment while ground based measurements are limited in wavelength range and need atmospheric effects corrections. This is why SSI modeling is necessary to understand the mechanism of the solar irradiance variability and to provide long and uninterrupted irradiance records to climate and Earth atmosphere scientists. Here we present COSI (COde for Solar Irradiance) model of the SSI variability. The COSI model is based on the Non local thermodynamic Equilibrium Spectral SYnthesis Code (NESSY). We validate NESSY by two independent datasets: - The SSI at solar minimum occurring in 2008, - The radius variation with wavelength and absolute values determined from PREMOS and BOS instruments onboard the PICARD spacecraft. Comparisons between modeling and measured SSI will be shown. However, since SSI measurements have an accuracy estimated between 2 to 3%, the comparison with the solar radius data provides a very important additional constrains on model. For that, 17 partial solar occultations by the Moon are used providing solar radii clearly showing the dependence of the solar radius with wavelength. These results are compared with the NESSY predictions. The agreement between NESSY and observations is within the model and measurements accuracy.

  17. Methods for routine control of irradiated food: Determination of the irradiation status of shellfish by thermoluminescence analysis

    NASA Astrophysics Data System (ADS)

    Schreiber, G. A.; Hoffmann, A.; Helle, N.; Bögl, K. W.

    1994-06-01

    In some countries, clearance has been given for treating certain types of shellfish by ionizing radiation in order to increase the shelf-life and to reduce health hazards which might be caused by contaminating microorganisms. In the present study, thermoluminescence (TL) analysis was used to examine the irradiation status of shellfish products purchased from local suppliers. For analysis minerals were isolated from the guts of the animals. Although on none of the examined products an irradiation treatment prior to analysis could be shown, the results obtained on non-irradiated and irradiated products have revealed that irradiation within the commercially used dose range can clearly be detected. Already first glow TL intensities of minerald indicated irradiation treatments. Normalized TL signals of non-irradiated and irradiated samples were clearly separated. By calculation of differences of TL intensities and TL signals between non-irradiated and irradiated samples in dependency of integration temperature an optimized integration area for glow curves was determined. The result of this study agree well with results obtained by two large-scale intercomparisons between food control laboratories to detect irradiation treatment of spices and herbal products as well as of fruit and vegetables by TL analysis of contaminating minerals.

  18. Survival after total body irradiation: Effects of irradiation of exteriorized small intestine. (Reannouncement with new availability information)

    SciTech Connect

    Vriesendorp, H.M.; Vigneulle, R.M.; Kitto, G.; Pelky, T.; Taylor, P.

    1993-12-31

    Rats receiving lethal irradiation to their exteriorized small intestine with pulsed 18 MVp bremsstrahlung radiation live about 4 days longer than rats receiving a dose of total-body irradiation (TBI) causing intestinal death. The LD50 for intestinal irradiation is approximately 6 Gy higher than the LD50 for intestinal death after TBI. Survival time after exteriorized intestinal irradiation can be decreased, by adding abdominal irradiation. Adding thoracic or pelvic irradiation does not alter survival time. Shielding of large intestine improves survival after irradiation of the rest of the abdomen while the small intestine is also shielded. The kinetics of histological changes in small intestinal tissues implicate the release of humoral factors after irradiation of the abdomen. Radiation injury develops faster in the first (proximal) 40 cm of the small intestine and is expressed predominantly as shortening in villus height. In the last (distal) 40 cm of the small intestine, the most pronounced radiation effect is a decrease in the number of crypts per millimeter. Irradiation (20 Gy) of the proximal small intestine causes 92 % mortality (median survival 10 days). Irradiation (20 Gy) of the distal small intestine causes 27% mortality (median survival > 30 days). In addition to depletion of crypt stem cells in the small intestine, other issues (humoral factors, irradiated subsection of the small intestine and shielding of the large intestine) appear to influence radiation-induced intestinal mortality.

  19. EFFECTS OF GAMMA IRRADIATION ON EPDM ELASTOMERS

    SciTech Connect

    Clark, E.

    2011-09-22

    Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer

  20. The spectral irradiance traceability chain at PTB

    SciTech Connect

    Sperfeld, P.; Pape, S.; Nevas, S.

    2013-05-10

    Spectral irradiance is a fundamental radiometric unit. Its application to measurement results requires qualified traceability to basic units of the international system of units (Systeme international d'unites, SI). The Physikalisch-Technische Bundesanstalt (PTB) is amongst other national metrological institutes (NMIs) responsible for the realization, maintenance and dissemination of various radiometric and photometric units based on and traceable to national standards. The unit of spectral irradiance is realized and represented by a blackbody-radiator as the national primary standard of the PTB. Based on Planck's radiation law, the irradiance is calculated and realized for any wavelength taking into account the exact knowledge of the radiation temperature and the geometrical parameters. Using a double-monochromator-based spectroradiometer system, secondary standard lamps can be calibrated by direct comparison to the blackbody-radiator (substitution method). These secondary standard lamps are then used at the PTB to calibrate standard lamps of customers. The customers themselves use these so-called transfer standards to calibrate their working standard lamps. These working standards are then used to calibrate own spectroradiometers or sources. This rather complex calibration chain is a common procedural method that for the customers generally leads to satisfying measurement results on site. Nevertheless, the standard lamps in use have to fulfill highest requirements concerning stability and reproducibility. Only this allows achieving comparably low transfer measurement uncertainties, which occur at each calibration step. Thus, the PTB is constantly investigating the improvement and further development of transfer standards and measurement methods for various spectral regions. The realization and dissemination of the spectral irradiance using the blackbody-radiator at the PTB is accomplished with worldwide approved minimized measurement uncertainties confirmed by