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Sample records for related trimethylammonium ions

  1. Calculations of kinetic isotope effects in the Hofmann eliminations of substituted (2-phenylethyl)trimethylammonium ions

    International Nuclear Information System (INIS)

    Lewis, D.E.; Sims, L.B.; Yamataka, H.; McKenna, J.

    1980-01-01

    Theoretical calculations of kinetic isotope effects (KIE) for the Hofmann elimination of the (2-phenylethyl)trimethylammonium ion (I,Z = H) have been carried out for an extensive series of transition-state models encompassing the Elcb-like region of the E2 mechanistic spectrum. The reaction coordinate employed corresponded to the irreversible fragmentation of the base-H'-C/sub β/-C/sub α/-N system, with proton transfer being the dominant contributor. Structural parameters (bond distances and angles) were related to the independent bond orders n/sub α-N/ and n/sub β-H'/ by empirical and semiempirical relationships. The most probable transition-state structure for the reaction was determined by interpolation of the experimental values for the β-D 2 and 15 N KIE into plots of the trends of the calculated KIE. The nonsolvated models obtained in this manner gave only poor agreement between calculated and experimental secondary deuterium (α-D 2 ) and leaving group deuterium [N(CD 3 )/sub x/(CH 3 )/sub 3-x/, x = 1 to 3) KIE; explicit consideration of differential solvation of the reactant and transition state afforded the most chemically reasonable resolution of these discrepancies. Using solvated models, transition-state structures were also determined for the Hofmann elimination of parasubstituted derivatives of I (Z = OCH 3 , Cl, CF 3 ). These transition states are related by a shift parallel to the central E2 diagogonal of an O'Ferrall-Jencks reaction diagram, as predicted by Thorton, indicating that, in the absence of other factors (differing solvent or base, etc.), the extent to which negative charge is accumulated at Cβ in the transition state is solely a factor of the leaving group. Both independent bond orders (n/sub α-N/ and n/sub β-H'/) exhibit a linear dependence on the sigma value of the substituent, allowing for the first time prediction of transition states

  2. Photocontrol of Voltage-Gated Ion Channel Activity by Azobenzene Trimethylammonium Bromide in Neonatal Rat Cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Sheyda R Frolova

    Full Text Available The ability of azobenzene trimethylammonium bromide (azoTAB to sensitize cardiac tissue excitability to light was recently reported. The dark, thermally relaxed trans- isomer of azoTAB suppressed spontaneous activity and excitation propagation speed, whereas the cis- isomer had no detectable effect on the electrical properties of cardiomyocyte monolayers. As the membrane potential of cardiac cells is mainly controlled by activity of voltage-gated ion channels, this study examined whether the sensitization effect of azoTAB was exerted primarily via the modulation of voltage-gated ion channel activity. The effects of trans- and cis- isomers of azoTAB on voltage-dependent sodium (INav, calcium (ICav, and potassium (IKv currents in isolated neonatal rat cardiomyocytes were investigated using the whole-cell patch-clamp technique. The experiments showed that azoTAB modulated ion currents, causing suppression of sodium (Na+ and calcium (Ca2+ currents and potentiation of net potassium (K+ currents. This finding confirms that azoTAB-effect on cardiac tissue excitability do indeed result from modulation of voltage-gated ion channels responsible for action potential.

  3. A microcalorimetry and binding study on interaction of dodecyl trimethylammonium bromide with wigeon hemoglobin

    International Nuclear Information System (INIS)

    Bordbar, A.K.; Moosavi-Movahedi, A.A.; Amini, M.K.

    2003-01-01

    The thermodynamic parameters for the binding of dodecyl trimethylammonium bromide (DTAB) with wigeon hemoglobin (Hb) in aqueous solution at various pH and 27 deg. C have been measured by equilibrium dialysis and titration microcalorimetry techniques. The Scatchard plots represent unusual features at neutral and alkaline pH and specific binding at acidic pH. This leads us to analyze the binding data by fitting the data to the Hill equation for multiclasses of binding sites. The best fit was obtained with the equation for one class at acidic pH and two classes at neutral and alkaline pH. The thermodynamic analysis of the binding process shows that the strength of binding at neutral pH is more than these at other pH values. This can be related to the more accessible hydrophobic surface area of wigeon hemoglobin at this pH. The endothermic enthalpy data which was measured by microcalorimetry confirms the binding data analysis and represents the more regular and stable structure of wigeon hemoglobin at neutral pH

  4. Energetic and binding properties of DNA upon interaction with dodecyl trimethylammonium bromide.

    Science.gov (United States)

    Bathaie, S Z; Moosavi-Movahedi, A A; Saboury, A A

    1999-02-15

    The interaction of dodecyl trimethylammonium bromide (DTAB), a cationic surfactant, with calf thymus DNA has been studied by various methods, including potentiometric technique using DTAB-selective plastic membrane electrode at 27 and 37 degreesC, isothermal titration microcalorimetry and UV spectrophotometry at 27 degreesC using 0.05 M Tris buffer and 0.01 M NaCl at pH 7.4. The free energy is calculated from binding isotherms on the basis of Wyman binding potential theory and the enthalpy of binding according to van't Hoff relation. The enthalpy of unfolding has been determined by subtraction of the enthalpy of binding from the microcalorimetric enthalpy. The results show that, after the interaction of first DTAB molecule to DNA (base molarity) through the electrostatic interaction, the second DTAB molecule also binds to DNA through electrostatic interaction. At this stage, the predom-inant DNA conformational change occurs. Afterwards up to 20 DTAB molecules, below the critical micelle concentration of DTAB, bind through hydrophobic interactions.

  5. POLY[3-(METHACRYLOYLAMINO)PROPYL]TRIMETHYLAMMONIUM CHLORIDE HYDROGEL. SYNTHESIS AND WATER-ABSORPTION CAPACITY.

    OpenAIRE

    Rivas, Bernabé L.; Canessa, Guido S.; Martínez, Esteban

    2000-01-01

    The radical polymerization of [3-(methacryloylamino)propyl]trimethylammonium chloride by using ammonium persulfate as initiator and N,N-methylene-bis-acrylamide as crosslinker reagent was carried out. The polymers were completely insoluble in water and characterized by FT IR spectroscopy and thermal analysis. The effect of the crosslinker reagent on the water sorption capacity was investigated. The highest water-absorption (46.6 g of water/ g of xerogel) was observed with the lowest mol% of c...

  6. Selectivity of the adsorption process of modified zeolite rock with hexadecyl trimethylammonium bromide in front to chromates and dichromates

    International Nuclear Information System (INIS)

    Salgado G, N.

    2011-01-01

    In the present investigation natural zeolite (clinoptilolite) from the Chihuahua state, which was conditioned with sodium chloride solution and subsequently modified with a hexadecyl trimethylammonium bromide solution was used to evaluate the removal of Cr (Vi) from chromate or dichromate solutions. The zeolite materials were characterized by scanning electron microscopy and X-ray diffraction. The surface area was also determined. The experiments were performed in a batch system, the influence of ph, contact time between phases were investigated and during the adsorption process was calculated the concentration of chromium ion present in aqueous solution (CrO 4 2- , Cr 2 O 7 2- ). The quantification of chromium removed from the aqueous solution by atomic absorption spectrometry technique was done. In order to understand the behaviour of the adsorption kinetics the pseudo first and pseudo second order models were applied, and to determine the adsorption capacity of the zeolite materials for Cr the Langmuir, Freundlich and Langmuir-Freundlich models were chosen. It was found that the removal efficiency of chromium ion is influenced by ph and the chemical species present: chromate or dichromate. The chromate and dichromate sorption kinetic data were best fitted to the pseudo-second and pseudo-first order models, respectively; and the Langmuir and Langmuir-Freundlich models described adequately the isotherms data considering a mono component system. In a mixture of Cr (Vi) ad CrO 4 2- and Cr 2 O 7 2- , the surfactant modified zeolite has a greater selectivity for Cr 2 O 7 2- ion than CrO 4 2- . In this case the Langmuir-Freundlich model described the adsorption isotherm behavior. (Author)

  7. Improvements in or relating to ion sources

    International Nuclear Information System (INIS)

    Clampitt, R.; Jefferies, D.K.

    1980-01-01

    An improved type of single-point source of metal ions is described. The source comprises an electrode with at least one non-hollow component made of a material which is wettable and non-corrosible by the liquid whose ions are to be emitted by the source. The radius of curvature of the termination of the electrode is such that a jet of the liquid material will be anchored to it under the influence of an electric field. Although the sources described are for lithium ions in particular and alkali metal ions in general, such sources can be used for other materials. (U.K.)

  8. Alkynylcarbenium ions and related unsaturated cations

    Energy Technology Data Exchange (ETDEWEB)

    Lukyanov, Sergey M; Koblik, Alla V; Muradyan, Lyudmila A [Institute of Physical and Organic Chemistry, Rostov State University, Rostov-on-Don (Russian Federation)

    1998-10-31

    Published data on carbenium ions containing carbon-carbon triple bonds both directly conjugated with the carbenium centre and separated from it are surveyed and described systematically. Ammonium, diazonium, iminium, phosphonium and iodonium cations containing alkynyl groups, which can be regarded as heteroanalogues of alkynylcarbenium ions, are also considered. The bibliography includes 283 references.

  9. Alkynylcarbenium ions and related unsaturated cations

    International Nuclear Information System (INIS)

    Lukyanov, Sergey M; Koblik, Alla V; Muradyan, Lyudmila A

    1998-01-01

    Published data on carbenium ions containing carbon-carbon triple bonds both directly conjugated with the carbenium centre and separated from it are surveyed and described systematically. Ammonium, diazonium, iminium, phosphonium and iodonium cations containing alkynyl groups, which can be regarded as heteroanalogues of alkynylcarbenium ions, are also considered. The bibliography includes 283 references

  10. A poly(alkyl methacrylate-divinylbenzene-vinylbenzyl trimethylammonium chloride) monolithic column for solid-phase microextraction.

    Science.gov (United States)

    Liu, Wan-Ling; Lirio, Stephen; Yang, Yicong; Wu, Lin-Tai; Hsiao, Shu-Ying; Huang, Hsi-Ya

    2015-05-22

    In this study, an organic polymer monolithic columns, which were prepared via in situ polymerization of alkyl methacrylate-ester (AMA), divinylbenzene (DVB) and vinylbenzyl trimethylammonium chloride (VBTA, charged monomer), were developed as adsorbent for solid-phase microextraction (SPME). Different parameters affecting the extraction efficiency for nine (9) non-steroidal anti-inflammatory drugs (NSAIDs) such as the ratio of the stearyl methacrylate (SMA) to DVB monomer, column length, sample pH, extraction flow rate and desorption solvent were investigated to obtain the optimal SPME condition. Also, the permeability for each poly(AMA-DVB-VBTA) monolithic column was investigated by adding porogenic solvent (poly(ethylene glycol), PEG). Using the optimized condition, a series of AMA-based poly(AMA-DVB-VBTA) monolith columns were developed to determine the effect the extraction efficiency of NSAIDs by varying the alkyl chain length of the methacrylate ester (methyl-, butyl-, octyl-, or lauryl-methacrylate; (MMA, BMA, OMA, LMA)). Results showed that decreasing the AMA chain length increases the extraction efficiency of some NSAIDs (i.e. sulindac (sul), naproxen (nap), ketoprofen (ket) and indomethacin (idm)). Among the poly(AMA-DVB-VBTA) monolithic columns, poly(BMA-DVB-VBTA) showed a highly repeatable extraction efficiency for NSAIDs with recoveries ranging from 85.0 to 100.2% with relative standard deviation (RSD) less than 6.8% (n=3). The poly(BMA-DVB-VBTA) can also be reused for at least 50 times without any significant effect in extraction efficiency for NSAIDs. Finally, using the established conditions, the poly(BMA-DVB-VBTA) was used to extract trace-level NSAIDs (100μgL(-1)) in river water with good recoveries ranging from 75.8 to 90.8% (RSD<14.9%). Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Kinematic relations in heavy-ion reactions

    International Nuclear Information System (INIS)

    Gippner, P.; Kalpakchieva, R.

    1988-01-01

    The present work gives a short overview of the non-relativistic kinematics of nuclear reactions derived on the basis of the conservation laws of energy and linear momentum. Section 2 contains kinematic relations valid for two-body reactions, sections 3 makes use of these relations to describe sequential fission as a special case of reactions with three particles in the exit channel. It is the aim of this work to comprise the kinematic formulae essential for planning of experiments, data analysis and critical examination of the obtained results. (author)

  12. Composite hydrogel based on surface modified mesoporous silica and poly[(2-acryloyloxy)ethyl trimethylammonium chloride

    International Nuclear Information System (INIS)

    Torres, Cecilia C.; Urbano, Bruno F.; Campos, Cristian H.; Rivas, Bernabé L.; Reyes, Patricio

    2015-01-01

    This work focused on the synthesis, characterization and water absorbency of a composite hydrogel based on poly[(2-acryloyloxy)ethyl trimethylammonium chloride] and mesoporous silica, MCM-41. The MCM-41 was synthesized and later surface functionalized with triethoxyvinylsilane (VTES) and 3-trimethoxysilylpropylmethacrylate (TMSPM) by a post-grafting procedure. The composite hydrogels were obtained by in-situ polymerization using a mixture of monomer, crosslinker and initiator in the presence of functionalized MCM-41. Diverse characterization techniques were used at the different stages of synthesis, namely, FT-IR, TEM, SEM, DRX, 29 Si and 13 C solid state NMR, and N 2 adsorption isotherms at 77 K. Finally, the water uptake performance of the composites was tested as a function of time, mesoporous silica loading and coupling agent used at the functionalization. The composites using non-functionalized MCM-41 reached the highest water uptake, whereas those composite with MCM-41 TMSPM exhibited the lowest sorption. - Highlights: • Hydrophilic crosslinked polymer-mesoporous silica was obtained. • Mesoporous silica MCM-41 was synthesized and functionalized with organosilane. • Functionalization of MCM-41 affects the water uptake of composite. • Mesoporous silica is covalently bound to the polymer acting as crosslinked point

  13. Composite hydrogel based on surface modified mesoporous silica and poly[(2-acryloyloxy)ethyl trimethylammonium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Cecilia C. [Department of Organic Chemistry, Faculty of Chemical Science, University of Concepción (Chile); Urbano, Bruno F., E-mail: burbano@udec.cl [Department of Polymer Chemistry, Faculty of Chemical Science, University of Concepción (Chile); Campos, Cristian H. [Department of Organic Chemistry, Faculty of Chemical Science, University of Concepción (Chile); Rivas, Bernabé L. [Department of Polymer Chemistry, Faculty of Chemical Science, University of Concepción (Chile); Reyes, Patricio [Department of Physical Chemistry, Faculty of Chemical Science, University of Concepción (Chile)

    2015-02-15

    This work focused on the synthesis, characterization and water absorbency of a composite hydrogel based on poly[(2-acryloyloxy)ethyl trimethylammonium chloride] and mesoporous silica, MCM-41. The MCM-41 was synthesized and later surface functionalized with triethoxyvinylsilane (VTES) and 3-trimethoxysilylpropylmethacrylate (TMSPM) by a post-grafting procedure. The composite hydrogels were obtained by in-situ polymerization using a mixture of monomer, crosslinker and initiator in the presence of functionalized MCM-41. Diverse characterization techniques were used at the different stages of synthesis, namely, FT-IR, TEM, SEM, DRX, {sup 29}Si and {sup 13}C solid state NMR, and N{sub 2} adsorption isotherms at 77 K. Finally, the water uptake performance of the composites was tested as a function of time, mesoporous silica loading and coupling agent used at the functionalization. The composites using non-functionalized MCM-41 reached the highest water uptake, whereas those composite with MCM-41 TMSPM exhibited the lowest sorption. - Highlights: • Hydrophilic crosslinked polymer-mesoporous silica was obtained. • Mesoporous silica MCM-41 was synthesized and functionalized with organosilane. • Functionalization of MCM-41 affects the water uptake of composite. • Mesoporous silica is covalently bound to the polymer acting as crosslinked point.

  14. Ion bombardment simulation: a review related to fusion radiation damage

    International Nuclear Information System (INIS)

    Brimhall, J.L.

    1975-01-01

    Prime emphasis is given to reviewing the ion bombardment data on the refractory metals molybdenum, niobium and vanadium which have been proposed for use in advanced fusion devices. The temperature and dose dependence of the void parameters are correlated among these metals. The effect of helium and hydrogen gas on the void parameters is also included. The similarities and differences of the response of these materials to high dose, high temperature radiation damage are evaluated. Comparisons are made with results obtained from stainless steel and nickel base alloys. The ion bombardment data is then compared and correlated, as far as possible, with existing neutron data on the refractory metals. The theoretically calculated damage state produced by neutrons and ions is also briefly discussed and compared to experimental data wherever possible. The advantages and limitations of ion simulation in relation to fusion radiation damage are finally summarized

  15. Facile preparation of polymer electrolytes based on the polymerized ionic liquid poly((4-vinylbenzyl)trimethylammonium bis(trifluoromethanesulfonylimide)) for lithium secondary batteries

    International Nuclear Information System (INIS)

    Li, Mingtao; Wang, Lu; Yang, Bolun; Du, Tingting; Zhang, Ying

    2014-01-01

    Graphical abstract: (A) The main components of PIL electrolytes, (B) A PIL electrolyte sample. - Highlights: • A new polymer electrolyte incorporating a DEME-TFSI liquid is prepared. • The ionic conductivity of the electrolytes reaches 7.58 × 10 −4 S cm −1 at 60 °C. • Batteries discharge 130 mAh g −1 at 0.1 C rates with good capacity retention. - Abstract: The polymer electrolytes based on a novel poly((4-vinylbenzyl)trimethylammonium bis(trifluoromethanesulfonylimide)) polymeric ionic liquid (PIL) as polymer host and containing DEME-TFSI ionic liquid, LiTFSI salt and nano silica are prepared. The polymer electrolyte is chemically stable even at a higher temperature of 60 °C in contact with lithium anode. Particularly, the electrolyte exhibits high lithium ion conductivity, wide electrochemical stability window and good lithium stripping/plating performance. When the IL content reaches 60% (the weight ratio of DEME-TFSI/PIL), the PIL electrolyte presents a higher ionic conductivity, and it is 7.58 × 10 −4 S cm −1 at 60 °C. Preliminary battery tests show that Li/LiFePO 4 cells with the PIL electrolytes are capable to deliver above 130 mAh g −1 at 60 °C with very good capacity retention

  16. Improvements in and relating to ion-exchange

    International Nuclear Information System (INIS)

    Heal, H.G.

    1975-01-01

    It has been found that the relatively expensive ion exchange materials normally used can be extensively replaced by relatively inexpensive material comprised of long-weathered basalt. This has been found to effect rapid and efficient ion exchange with a capacity comparable with, and in some cases greater than, the usual artificial materials. The basalt should contain at least 50% by weight of particles of size below 3cm mesh. Olivine basalt has proved particularly effective. Examples given include removal of Cu and Co, application to water softening, and to the removal of 137 Cs from milk. Other applications mentioned include removal of Ca, 90 Sr, Pb, Zn, Hg, Ni, and Cr, extraction of metal ions from seawater, purification of industrial effluents, etc. (U.K.)

  17. Structural and interactional behaviour of aqueous mixture of room temperature ionic liquid; 2-hydroxyethyl-trimethylammonium L-lactate

    International Nuclear Information System (INIS)

    Chaudhary, Ganga Ram; Bansal, Shafila; Mehta, S.K.; Ahluwalia, A.S.

    2014-01-01

    Highlights: • Thermophysical and spectroscopic properties of aqueous mixtures 2-[HE3MA]LAC have been measured. • Effect of temperature on thermophysical properties has also been studied. • Stronger intermolecular have been observed between [HE3MA]LAC and H 2 O. • Magnitude of interactions decreases with the rise in temperature. • Spectroscopic studies shows interactions between -N + -(CH 3 ) 3 with -OH - group and COO − with -H + of IL and H 2 O. - Abstract: In order to understand the molecular interactions between the green solvent system, (water + lactate based ionic liquid); 2-hydroxyethyl-trimethylammonium L-lactate ([(C 2 H 4 OH)(CH 3 ) 3 N][Lactate]), the thermophysical properties viz. density ρ, speed of sound u, specific conductivity κ, refractive index n D and spectroscopic properties viz. IR, 1 H and 13 C NMR have been investigated over the whole composition range at atmospheric pressure with temperature varied from (293.15 to 323.15) K. To gain more insight of intermolecular interactions occurring in the aqueous mixture of [(C 2 H 4 OH)(CH 3 ) 3 N][Lactate], intermolecular free length L f , acoustic impedance Z, relative association R A , excess molar volume V E , deviations in isentropic compressibility ΔK S , partial molar excess volume V i E , partial molar deviations in isentropic compressibility ΔK S,i , deviation in specific conductivity Δκ and deviation in refractive index Δn D have been predicted as a function of IL concentration over the whole composition range. These results have been fitted to the Redlich–Kister polynomial. A large deviation from ideality has been observed on mixing water and [(C 2 H 4 OH)(CH 3 ) 3 N][Lactate] which are due to the formation of strong intermolecular hydrogen bonding between the two molecules. Also, it has been noticed that the mixture of water and [(C 2 H 4 OH)(CH 3 ) 3 N][Lactate] became warm that indicates mixing of these two components is exothermic. Thermodynamic and spectroscopic data

  18. The synchrotron and its related technology for ion beam therapy

    International Nuclear Information System (INIS)

    Hiramoto, Kazuo; Umezawa, Masumi; Saito, Kazuyoshi; Tootake, Satoshi; Nishiuchi, Hideaki; Hara, Shigemistu; Tanaka, Masanobu; Matsuda, Koji; Sakurabata, Hiroaki; Moriyama, Kunio

    2007-01-01

    Hitachi has developed several new technologies for the synchrotron and its related system to realize reliable and flexible operation of a proton therapy system. Especially important among them are a non-resonant RF acceleration cavity using FINEMET core with multiple power feeding and radio frequency driven beam extraction technique (RF-DE) for a synchrotron. Various treatment operations such as variable acceleration energy or respiration gating became possible and simple due to the above technique. For beam transport, a beam steering method for the beam, using transfer matrix realizes quick and precise correction of the beam orbit. A compact microwave ion source has also been developed for the injector to obtain further higher reliability and availability. Most of these technologies are also effective to enhance the reliability and flexibility of other ion beam therapy systems

  19. Radioluminescence of synthetic quartz related to alkali ions

    Energy Technology Data Exchange (ETDEWEB)

    Martini, M., E-mail: m.martini@unimib.it [Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); INFN-Sezione di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); Fasoli, M. [Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); Galli, A. [Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); Istituto di Fotonica e Nanostrutture, IFN-CNR (Italy); Villa, I. [Dipartimento di Scienza dei Materiali, Universita degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano (Italy); Guibert, P. [IRAMAT-CRP2A (Institut de recherche sur les Archeomateriaux), UMR no. 5060, CNRS-Universite Bordeaux III, F-33607 Pessac (France)

    2012-04-15

    The radioluminescence (RL) of synthetic quartzes (GEMMA Quartz and Crystal Company) has been measured at room temperature. Some samples were treated by electrodiffusion ('sweeping') in order to change the concentrations of alkali ions, mainly Li{sup +} and Na{sup +}, which in quartz are known to be linked to Al ions, substitutional for Si ions. The RL emission spectra show evidence of a role of alkali ions in affecting some specific emissions. All the spectra could be analysed as composed of four bands in the blue and UV region. Specifically, the well known blue emission at around 470 nm was seen to be composed by two bands at 430 nm (2.86 eV) and at 485 nm (2.53 eV). Effects of irradiation, during the RL measurements, were clearly seen only in the 'Li swept in' sample, namely an increase in the 485 nm band intensity and a decrease in the 430 nm band one. The previously reported UV emission was detected at 355 nm (3.44 eV) in all the samples, being the most intense band in the 'swept out' sample. A further UV emission was detected at 315 nm (3.94 eV), more intense in untreated samples. Possible assignments of the detected emission bands are discussed in relation to the defects of quartz, specifically focusing on the Al centres that are most affected by sweeping procedures. - Highlights: Black-Right-Pointing-Pointer Contribution to the understanding of relationships between defects in quartz and luminescence emissions. Black-Right-Pointing-Pointer Role of charge compensators at substitutional Al sites in the optical properties of quartz. Black-Right-Pointing-Pointer Evidence of the double nature of the 'blue emission' (around 470 nm).

  20. Review on heavy ion radiotherapy facilities and related ion sources (invited)

    International Nuclear Information System (INIS)

    Kitagawa, A.; Fujita, T.; Muramatsu, M.; Biri, S.; Drentje, A. G.

    2010-01-01

    Heavy ion radiotherapy awakens worldwide interest recently. The clinical results obtained by the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan have clearly demonstrated the advantages of carbon ion radiotherapy. Presently, there are four facilities for heavy ion radiotherapy in operation, and several new facilities are under construction or being planned. The most common requests for ion sources are a long lifetime and good stability and reproducibility. Sufficient intensity has been achieved by electron cyclotron resonance ion sources at the present facilities.

  1. Relative ion expansion velocity in laser-produced plasmas

    International Nuclear Information System (INIS)

    Goldsmith, S.; Moreno, J.C.; Griem, H.R.; Cohen, L.; Richardson, M.C.

    1988-01-01

    The spectra of highly ionized titanium, TiXIII through TiXXI, and CVI Lyman lines were excited in laser-produced plasmas. The plasma was produced by uniformly irradiating spherical glass microballoons coated with thin layers of titanium and parylene. The 24-beam Omega laser system produced short, 0.6 ns, and high intensity, 4 x 10 14 W/cm, 2 laser pulses at a wavelength of 351 nm. The measured wavelength for the 2p-3s TiXIII resonance lines had an average shift of +0.023 A relative to the CVI and TiXX spectral lines. No shift was found between the CVI, TiXIX, and TiXX lines. The shift is attributed to a Doppler effect, resulting from a difference of (2.6 +- 0.2) x 10 7 cm/s in the expansion velocities of TiXIX and TiXX ions compared to TiXIII ions

  2. Distributed ion pump related transverse instability in CESR

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J T; Holmquist, T [Cornell Univ., Ithaca, NY (United States). Lab. of Nuclear Studies

    1996-08-01

    An anomalous damping or growth of transverse coupled bunch modes is observed in the Cornell Electron Storage Ring (CESR). The growth rates and tune shifts of these modes are a highly nonlinear function of current. Unlike an instability produced by the coupling impedance of the vacuum chamber, the magnitude of the growth rate first increases, then declines, as the beam current is increased. The effect is known to be related to the operation of the distributed ion pumps, as it disappears when the pumps are not powered. We review the observations of this effect, and show that it can be explained by the presence of electrons trapped in the CESR chamber by the field of the dipole magnets and the electrostatic leakage field of the distributed ion pumps. Photoelectrons are introduced into the chamber by synchrotron radiation and can be captured in or ejected from the chamber by the passage of the beam. The transverse position of the beam thus modulates the trapped photoelectron charge density, which in turn deflects the beam, creating growth or damping and a tune shift for each coupled bunch mode. Predictions of the dependence of growth rate and tune shift on bunch current and bunch pattern by a numerical model of this process are in approximate agreement with observations. (author)

  3. Recent radioactive ion beam program at RIKEN and related topics

    Indian Academy of Sciences (India)

    Keywords. RIKEN; radioactive ion beams; magic numbers. PACS No. 21.10.-k. 1. Introduction. In RIKEN, there are several heavy ion accelerators. Main accelerator is the RIKEN ring cyclotron (RRC) with K = 540, that has been operated from 1986. The RRC has two injectors; one is heavy ion linear accelerator that has been ...

  4. Production and Characterization of Desmalonichrome Relative Binding Affinity for Uranyl Ions in Relation to Other Siderophores

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Kai-For; Dai, Ziyu; Wunschel, David S.

    2016-06-24

    Siderophores are Fe binding secondary metabolites that have been investigated for their uranium binding properties. Much of the previous work has focused on characterizing hydroxamate types of siderophores, such as desferrioxamine B, for their uranyl binding affinity. Carboxylate forms of these metabolites hold potential to be more efficient chelators of uranyl, yet they have not been widely studied and are more difficult to obtain. Desmalonichrome is a carboxylate siderophore which is not commercially available and so was obtained from the ascomycete fungus Fusarium oxysporum cultivated under Fe depleted conditions. The relative affinity for uranyl binding of desmalonichrome was investigated using a competitive analysis of binding affinities between uranyl acetate and different concentrations of iron(III) chloride using electrospray ionization mass spectrometry (ESI-MS). In addition to desmalonichrome, three other siderophores, including two hydroxamates (desferrioxamine B and desferrichrome) and one carboxylate (desferrichrome A) were studied to understand their relative affinities for the uranyl ion at two pH values. The binding affinities of hydroxymate siderophores to uranyl ion were found to decrease to a greater degree at lower pH as the concentration of Fe (III) ion increases. On the other hand, lowering pH has little impact on the binding affinities between carboxylate siderophores and uranyl ion. Desmalonichrome was shown to have the greatest relative affinity for uranyl at any pH and Fe(III) concentration. These results suggest that acidic functional groups in the ligands are critical for strong chelation with uranium at lower pH.

  5. New lithium-ion conducting perovskite oxides related to (Li, La)TiO3

    Indian Academy of Sciences (India)

    Unknown

    We describe the synthesis and lithium-ion conductivity of new perovskite-related oxides ... work on lithium-ion conducting perovskite oxides containing d0 cations. Keywords. ..... On the other hand, Nb/Ta compounds show a higher conductivity.

  6. Effects of the instability enhanced friction on relative ion densities in a two-ion species low-temperature plasma

    Science.gov (United States)

    Vukovic, Mirko

    2011-10-01

    The instability enhanced friction theory of Baalrud & Hegna (Phys. Plasmas 18, 023505 (2011)) predicts that for comparable ion densities the ions nearly reach a common velocity near the sheath edge in a low temperature plasma. The theory was experimentally confirmed by Yip, Hershkowitz, & Severn (Phys. Rev. Letters 104, 225003 (2010)). We will explore the effects of the theory on relative ion densities in a numerical simulation of an Ar/Xe plasma. Results for a 0D plasma model (Lieberman, Lichtenberg, Principles of Plasma Discharges and Materials Processing, 2005) will be presented.

  7. Ion Chromatographic Analyses of Sea Waters, Brines and Related Samples

    Directory of Open Access Journals (Sweden)

    Nataša Gros

    2013-06-01

    Full Text Available This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as completely as possible. The sections—Selected Anions, Selected Cations and Metals—follow. The most essential experimental conditions used in different methods are summarized in tables for a rapid comparison. Techniques encountered in the reviewed articles comprise: direct determinations of ions in untreated samples with ion- or ion-exclusion chromatography, or electrostatic ion chromatography; matrix elimination with column-switching; pre-concentration with a chelation ion chromatography and purge-and-trap pre-concentration. Different detection methods were used: non-suppressed conductometric or suppressed conductometric, direct spectrometric or spectrometric after a post-column derivetization, and inductively coupled plasma in combination with optical emission or mass spectrometry.

  8. Scaling relations in elastic scattering cross sections between multiply charged ions and hydrogen

    International Nuclear Information System (INIS)

    Rodriguez, V.D.

    1991-01-01

    Differential elastic scattering cross sections of bare ions from hydrogen are calculated using the eikonal approximation. The results satisfy a scaling relation involving the scattering angle, the ion charge and a factor related to the ion mass. A semiclassical explanation in terms of a distant collision hypothesis for small scattering angle is proposed. A unified picture of related scaling rules found in direct processes is discussed. (author)

  9. Ion Chromatographic Analyses of Sea Waters, Brines and Related Samples

    OpenAIRE

    Nataša Gros

    2013-01-01

    This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as com...

  10. RAFT-mediated synthesis of cationic poly[(ar-vinylbenzyl)trimethylammonium chloride] brushes for quantitative DNA immobilization

    International Nuclear Information System (INIS)

    Demirci, Serkan; Caykara, Tuncer

    2013-01-01

    The synthesis of cationic poly[(ar-vinylbenzyl)trimethylammonium chloride)] [poly(VBTAC)] brushes was achieved via reversible addition-fragmentation chain transfer (RAFT) polymerization and used for quantitative DNA immobilization. Initially, silicon surfaces were modified with RAFT chain transfer agent by utilizing an amide reaction involving a silicon wafer modified with allylamine and 4-cyanopentanoic acid dithiobenzoate (CPAD). Poly(VBTAC) brushes were then prepared via RAFT-mediated polymerization from the surface immobilized CPAD. Various characterization techniques including ellipsometry, X-ray photoelectron spectroscopy, grazing angle-Fourier transform infrared spectroscopy, atomic force microscopy and contact-angle goniometer were used to characterize the immobilization of CPAD on the silicon wafer and the subsequent polymer formation. The addition of free CPAD was required for the formation of well-defined polymer brushes, which subsequently resulted in the presence of free polymer chains in solution. The free polymer chains were isolated and used to estimate the molecular weights and polydispersity index of chains attached to the surface. Moreover, from atomic force microscopy and ellipsometry measurements, it was also determined that the density of immobilized DNA on the cationic poly(VBTAC) brushes can be quantitatively controlled by adjusting the solution concentration. Highlights: ► The cationic poly(VBTAC) brushes were prepared by RAFT polymerization. ► Grafting density of cationic poly(VBTAC) brushes was as high as 0.76 chains/nm 2 . ► The cationic poly(VBTAC) brushes were used for quantitative DNA immobilization.

  11. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy, and Related Fields

    International Nuclear Information System (INIS)

    Grisham, L.R.; Kwan, J.W.

    2008-01-01

    Some years ago it was suggested that halogen negative ions (1)could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion-ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component--positive ions, negative ions, and electrons--can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion-ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed

  12. Perspective on the Role of Negative Ions and Ion-Ion Plasmas in Heavy Ion Fusion Science, Magnetic Fusion Energy,and Related Fields

    International Nuclear Information System (INIS)

    Grisham, L.R.; Kwan, J.W.

    2008-01-01

    Some years ago it was suggested that halogen negative ions could offer a feasible alternative path to positive ions as a heavy ion fusion driver beam which would not suffer degradation due to electron accumulation in the accelerator and beam transport system, and which could be converted to a neutral beam by photodetachment near the chamber entrance if desired. Since then, experiments have demonstrated that negative halogen beams can be extracted and accelerated away from the gas plume near the source with a surviving current density close to what could be achieved with a positive ion of similar mass, and with comparable optical quality. In demonstrating the feasibility of halogen negative ions as heavy ion driver beams, ion - ion plasmas, an interesting and somewhat novel state of matter, were produced. These plasmas, produced near the extractor plane of the sources, appear, based upon many lines of experimental evidence, to consist of almost equal densities of positive and negative chlorine ions, with only a small component of free electrons. Serendipitously, the need to extract beams from this plasma for driver development provides a unique diagnostic tool to investigate the plasma, since each component - positive ions, negative ions, and electrons - can be extracted and measured separately. We discuss the relevance of these observations to understanding negative ion beam extraction from electronegative plasmas such as halogens, or the more familiar hydrogen of magnetic fusion ion sources. We suggest a concept which might improve negative hydrogen extraction by the addition of a halogen. The possibility and challenges of producing ion - ion plasmas with thin targets of halogens or, perhaps, salt, is briefly addressed.

  13. Recent radioactive ion beam program at RIKEN and related topics

    Indian Academy of Sciences (India)

    Recent experimental programs at RIKEN concerning RI beams are reviewed. RIKEN has the ring cyclotron (RRC) with high intense heavy-ion beams and large acceptance fragment separator, RIPS. The complex can provide high intense RI-beams. By using the high intense RI-beams, a variety of experiments have been ...

  14. Selectivity of the adsorption process of modified zeolite rock with hexadecyl trimethylammonium bromide in front to chromates and dichromates; Selectividad del proceso de adsorcion de roca zeolitica modificada con bromuro de hexadeciltrimetilamonio frente a cromatos y dicromatos

    Energy Technology Data Exchange (ETDEWEB)

    Salgado G, N.

    2011-07-01

    In the present investigation natural zeolite (clinoptilolite) from the Chihuahua state, which was conditioned with sodium chloride solution and subsequently modified with a hexadecyl trimethylammonium bromide solution was used to evaluate the removal of Cr (Vi) from chromate or dichromate solutions. The zeolite materials were characterized by scanning electron microscopy and X-ray diffraction. The surface area was also determined. The experiments were performed in a batch system, the influence of ph, contact time between phases were investigated and during the adsorption process was calculated the concentration of chromium ion present in aqueous solution (CrO{sub 4}{sup 2-}, Cr{sub 2}O{sub 7}{sup 2-}). The quantification of chromium removed from the aqueous solution by atomic absorption spectrometry technique was done. In order to understand the behaviour of the adsorption kinetics the pseudo first and pseudo second order models were applied, and to determine the adsorption capacity of the zeolite materials for Cr the Langmuir, Freundlich and Langmuir-Freundlich models were chosen. It was found that the removal efficiency of chromium ion is influenced by ph and the chemical species present: chromate or dichromate. The chromate and dichromate sorption kinetic data were best fitted to the pseudo-second and pseudo-first order models, respectively; and the Langmuir and Langmuir-Freundlich models described adequately the isotherms data considering a mono component system. In a mixture of Cr (Vi) ad CrO{sub 4}{sup 2-} and Cr{sub 2}O{sub 7}{sup 2-}, the surfactant modified zeolite has a greater selectivity for Cr{sub 2}O{sub 7}{sup 2-} ion than CrO{sub 4}{sup 2-}. In this case the Langmuir-Freundlich model described the adsorption isotherm behavior. (Author)

  15. Chemical equilibrium relations used in the fireball model of relativistic heavy ion reactions

    International Nuclear Information System (INIS)

    Gupta, S.D.

    1978-01-01

    The fireball model of relativistic heavy-ion collision uses chemical equilibrium relations to predict cross sections for particle and composite productions. These relations are examined in a canonical ensemble model where chemical equilibrium is not explicitly invoked

  16. Atom probe field ion microscopy and related topics: A bibliography 1989

    International Nuclear Information System (INIS)

    Miller, M.K.; Hawkins, A.R.; Russell, K.F.

    1990-12-01

    This bibliography includes references related to the following topics: atom probe field ion microscopy (APFIM), field ion spectroscopy (FIM), field emission microscopy (FEM), liquid metal ion sources (LMIS), scanning tunneling microscopy (STM), and theory. Technique-orientated studies and applications are included. This bibliography covers the period 1989. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications

  17. Hofmann elimination of p-nitrophenylethyl-1-C-14-trimethylammonium bromide: a carbon-14 isotope effect study (Preprint no. AR-24)

    International Nuclear Information System (INIS)

    Ramamurthy, T.V.; Fry, Arthur

    1991-01-01

    The alpha carbon isotope effects in the Hofmann elimination of p-nitrophenylethyl-1-C-14-trimethylammonium bromide compound have been measured under changing buffer concentrations with a view to correlate mechanistic change. Since there are alpha-carbon isotope effects and the effects are small it is quite likely that the reaction is of the ElcB type, predominately irreversible, with the incursion of slightly increasing fractions of reaction by the reversible mechanism as the buffer concentration is increased. (author). 4 refs., 2 tab

  18. Preparation of Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

    International Nuclear Information System (INIS)

    Li Xiaolong; Liu Guoqiang; Yan Wei; Chu, Paul K.; Yeung, Kelvin W.K.; Wu Shuilin; Yi Changfeng; Xu Zushun

    2012-01-01

    Cationic magnetic polymer particles Fe 3 O 4 /poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe 3 O 4 , styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV–vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier. - Highlights: ► A new type of cationic magnetic polymer particles was synthesized by emulsifier-free emulsion polymerization. ► Structural, morphological, and magnetic properties of the composite were evaluated. ► The interaction between cationic magnetic polymer particles with DNA was confirmed by zeta potential measurements. ► UV–vis spectrophotometry, fluorescent spectroscopy and agarose gel electrophoresis. ► This process may have potential applications to gene carrier and DNA separation.

  19. Preparation of Fe 3O 4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

    Science.gov (United States)

    Li, Xiaolong; Liu, Guoqiang; Yan, Wei; Chu, Paul K.; Yeung, Kelvin W. K.; Wu, Shuilin; Yi, Changfeng; Xu, Zushun

    2012-04-01

    Cationic magnetic polymer particles Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe3O4, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier.

  20. Workshop summary. Biomedical and Space-Related Research with Heavy Ions at the BEVALAC

    Science.gov (United States)

    Schimmerling, W.; Curtis, S. B.

    1989-01-01

    The authors provide an overview of papers presented at a workshop on Biomedical and Space-Related Research with Heavy Ions at the BEVALAC at Lawrence Berkeley Laboratory. Goals of the meeting were to determine the critical experiments using heavy ions as probes in radiation physics, radiation chemistry, macromolecular and cellular biology, evolution science, basic neurophysiology, and medical therapies; how beam lines and facilities at Lawrence Berkeley Laboratory can be improved for these experiments; and implications in priorities and funding for national policy. Workshop topics included physics and facilities, cellular and molecular biology, tissue radiobiology, and the future of heavy ion research.

  1. A comparative study on the thermophysical properties for two bis[(trifluoromethyl)sulfonyl]imide-based ionic liquids containing the trimethyl-sulfonium or the trimethyl-ammonium cation in molecular solvents.

    Science.gov (United States)

    Couadou, Erwan; Jacquemin, Johan; Galiano, Hervé; Hardacre, Christopher; Anouti, Mérièm

    2013-02-07

    Herein, we present a comparative study of the thermophysical properties of two homologous ionic liquids, namely, trimethyl-sulfonium bis[(trifluoromethyl)sulfonyl]imide, [S(111)][TFSI], and trimethyl-ammonium bis[(trifluoromethyl)sulfonyl]imide, [HN(111)][TFSI], and their mixtures with propylene carbonate, acetonitrile, or gamma butyrolactone as a function of temperature and composition. The influence of solvent addition on the viscosity, conductivity, and thermal properties of IL solutions was studied as a function of the solvent mole fraction from the maximum solubility of IL, x(s), in each solvent to the pure solvent. In this case, x(s) is the composition corresponding to the maximum salt solubility in each liquid solvent at a given temperature from 258.15 to 353.15 K. The effect of temperature on the transport properties of each binary mixture was then investigated by fitting the experimental data using Arrhenius' law and the Vogel-Tamman-Fulcher (VTF) equation. The experimental data shows that the residual conductivity at low temperature, e.g., 263.15 K, of each binary mixture is exceptionally high. For example, conductivity values up to 35 and 42 mS·cm(-1) were observed in the case of the [S(111)][TFSI] + ACN and [HN(111)][TFSI] + ACN binary mixtures, respectively. Subsequently, a theoretical approach based on the conductivity and on the viscosity of electrolytes was formulated by treating the migration of ions as a dynamical process governed by ion-ion and solvent-ion interactions. Within this model, viscosity data sets were first analyzed using the Jones-Dole equation. Using this theoretical approach, excellent agreement was obtained between the experimental and calculated conductivities for the binary mixtures investigated at 298.15 K as a function of the composition up to the maximum solubility of the IL. Finally, the thermal characterization of the IL solutions, using DSC measurements, showed a number of features corresponding to different solid

  2. Ion diffusion related to structure in molten salts

    International Nuclear Information System (INIS)

    Tosi, M.P.

    1996-08-01

    A model first developed by Zwanzig to derive transport coefficients in cold dense fluids directly from the Green-Kubo time correlation formulae allows one to relate macroscopic diffusion coefficients to the local fluid structure. Applications to various ionic diffusion processes in molten salts are reviewed. Consequences of partial structural quenching are also discussed. (author). 28 refs, 3 tabs

  3. Bragg peak and relative biological efficiency of different ions

    Czech Academy of Sciences Publication Activity Database

    Lokajíček st., Miloš; Judas, Libor; Kundrát, Pavel

    2002-01-01

    Roč. 64, Suppl. 1 (2002), S309-S309 ISSN 0167-8140 R&D Projects: GA AV ČR(CZ) KSK4055109 Keywords : Bragg peak * relative biological efficisncy * radiological mechanism Subject RIV: CC - Organic Chemistry Impact factor: 2.838, year: 2002

  4. Dispersion relation of Raman FEL with helical Wiggler and ion channel

    International Nuclear Information System (INIS)

    Hosseinalinezhad, M.; Bahmani, M.; Hasanbeigi, A.; Salehkoutahi, M.

    2012-01-01

    In this paper the theory of free electron laser with helical wiggler and ion channel guiding has been presented. The equations of motion for an electron have been analyzed. A formula for the dispersion relation is then derived in the low-gain-per-pass limit. The results of a numerical study of the growth rate enhancement due to the ion channel are presented and discussed.

  5. Photoluminescence of Se-related oxygen deficient center in ion-implanted silica films

    International Nuclear Information System (INIS)

    Zatsepin, A.F.; Buntov, E.A.; Pustovarov, V.A.; Fitting, H.-J.

    2013-01-01

    The results of low-temperature time-resolved photoluminescence (PL) investigation of thin SiO 2 films implanted with Se + ions are presented. The films demonstrate an intensive PL band in the violet spectral region, which is attributed to the triplet luminescence of a new variant of selenium-related oxygen deficient center (ODC). The main peculiarity of the defect energy structure is the inefficient direct optical excitation. Comparison with spectral characteristics of isoelectronic Si-, Ge- and SnODCs show that the difference in electronic properties of the new center is related to ion size factor. It was established that the dominating triplet PL excitation under VUV light irradiation is related to the energy transfer from SiO 2 excitons. A possible model of Se-related ODC is considered. -- Highlights: • The low-temperature photoluminescence of thin SiO 2 films implanted with Se + ions was studied. • The 3.4 eV PL band was attributed to triplet luminescence of Se-related ODC. • The peculiarity of SeODC electronic properties is related to ion size factor. • The dominating VUV excitation of triplet PL is related to energy transfer from SiO 2 excitons. • A possible model of Se-related ODC is considered

  6. Synthesis and properties of the para-trimethylammonium analogues of green fluorescence protein (GFP) chromophore: The mimic of protonated GFP chromophore.

    Science.gov (United States)

    Fanjiang, Ming-Wei; Li, Ming-Ju; Sung, Robert; Sung, Kuangsen

    2018-04-01

    At low pH, protons from the external, bulk solution can protonate the phenoxide group of the p-HBDI chromophore in wild-type green fluorescent protein (wtGFP) and its mutants, and likely continue to tentatively protonate the phenol hydroxyl group of the same chromophores. Because the protonated GFP chromophore is a transient, we prepare the stable p-trimethylammonium analogues (2a and 2b) of the GFP chromophore to mimic it and explore their properties. What we found is that the p-trimethylammonium analogues of the GFP chromophore have the highly electrophilic amidine carbon, blue-shifted electronic absorption, smaller molar absorptivity, smaller fluorescent quantum yield, and faster E-Z thermoisomerization rate. The amidine carbon of the p-trimethylammonium analogue (2b) of the GFP chromophore is the only site that is attacked by very weak nucleophile of water, resulting in ring-opening of the imidazolinone moiety. The half-life of its decay rate in D 2 O is around 33 days. Actually, acid-catalyzed hydrolysis of p-HBDI also results in ring-opening of the imidazolinone moiety. The ratio of the acid-catalyzed hydrolysis rate constants [k obs (p-HBDI)/k obs (1b)] between p-HBDI and 1b (p-dimethylammonium analogue of the GFP chromophore) is dramatically increased from 0.30 at pH = 2 to 0.63 at pH = 0. This is the evidence that more and more phenol hydroxyl groups of p-HBDI are tentatively protonated in a low-pH aqueous solution and that accelerates hydrolysis of p-HBDI in the way similar to the quaternary ammonium derivatives 2a and 2b in water. With this view point, 2a and 2b still can partially mimic the cationic p-HBDI with the protonated phenol hydroxyl group. Implication of the experiment is that the amidine carbon of the chromophore in wtGFP and its mutants at very low pH should be highly electrophilic. Whether ring-opening of the imidazolinone moiety of the GFP chromophore would occur or not depends on if water molecules can reach the amidine carbon of

  7. N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride: An immune-enhancing adjuvant for hepatitis E virus recombinant polypeptide vaccine in mice.

    Science.gov (United States)

    Tao, Wei; Zheng, Hai-Qun; Fu, Ting; He, Zhuo-Jing; Hong, Yan

    2017-08-03

    Adjuvants are essential for enhancing vaccine potency by improving the humoral and/or cell-mediated immune response to vaccine antigens. This study was performed to evaluate the immuno-enhancing characteristic of N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (HTCC), the cationically modified chitosan, as an adjuvant for hepatitis E virus (HEV) recombinant polypeptide vaccine. Animal experiments showed that HTCC provides adjuvant activity when co-administered with HEV recombinant polypeptide vaccine by intramuscularly route. Vaccination using HTCC as an adjuvant was associated with increases of the serum HEV-specific IgG antibodies, splenocytes proliferation and the growths of CD4 + CD8 - T lymphocytes and IFN-γ-secreting T lymphocytes in peripheral blood. These findings suggested that HTCC had strong immuno-enhancing effect. Our findings are the first to demonstrate that HTCC is safe and effective in inducing a good antibody response and stimulating Th1-biased immune responses for HEV recombinant polypeptide vaccine.

  8. Relative clinical effectiveness of carbon ion radiotherapy. Theoretical modelling for H and N tumours

    International Nuclear Information System (INIS)

    Antonovic, Laura; Toma-Dasu, Iuliana; Dasu, Alexandru; Furusawa, Yoshiya

    2015-01-01

    Comparison of the efficiency of photon and carbon ion radiotherapy (RT) administered with the same number of fractions might be of limited clinical interest, since a wide range of fractionation patterns are used clinically today. Due to advanced photon treatment techniques, hypofractionation is becoming increasingly accepted for prostate and lung tumours, whereas patients with head and neck tumours still benefit from hyperfractionated treatments. In general, the number of fractions is considerably lower in carbon ion RT. A clinically relevant comparison would be between fractionation schedules that are optimal within each treatment modality category. In this in silico study, the relative clinical effectiveness (RCE) of carbon ions was investigated for human salivary gland tumours, assuming various radiation sensitivities related to their oxygenation. The results indicate that, for hypoxic tumours in the absence of reoxygenation, the RCE (defined as the ratio of D 50 for photons to carbon ions) ranges from 3.5 to 5.7, corresponding to carbon ion treatments given in 36 and 3 fractions, respectively, and 30 fractions for photons. Assuming that interfraction local oxygenation changes take place, results for RCE are lower than that for an oxic tumour if only a few fractions of carbon ions are used. If the carbon ion treatment is given in more than 12 fractions, the RCE is larger for the hypoxic than for the well-oxygenated tumour. In conclusion, this study showed that in silico modelling enables the study of a wide range of factors in the clinical considerations and could be an important step towards individualisation of RT treatments. (author)

  9. Atom probe field ion microscopy and related topics: A bibliography 1993

    Energy Technology Data Exchange (ETDEWEB)

    Godfrey, R.D.; Miller, M.K.; Russell, K.F.

    1994-10-01

    This bibliography, covering the period 1993, includes references related to the following topics: atom probe field ion microscopy (APFIM), field emission (FE), and field ion microscopy (FIM). Technique-oriented studies and applications are included. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications. To reduce the length of this document, the references have been reduced to the minimum necessary to locate the articles. The references are listed alphabetically by authors, an Addendum of references missed in previous bibliographies is included.

  10. Noncovalent Complexation of Monoamine Neurotransmitters and Related Ammonium Ions by Tetramethoxy Tetraglucosylcalix[4]arene

    Science.gov (United States)

    Torvinen, Mika; Kalenius, Elina; Sansone, Francesco; Casnati, Alessandro; Jänis, Janne

    2012-02-01

    The noncovalent complexation of monoamine neurotransmitters and related ammonium and quaternary ammonium ions by a conformationally flexible tetramethoxy glucosylcalix[4]arene was studied by electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry. The glucosylcalixarene exhibited highest binding affinity towards serotonin, norepinephrine, epinephrine, and dopamine. Structural properties of the guests, such as the number, location, and type of hydrogen bonding groups, length of the alkyl spacer between the ammonium head-group and the aromatic ring structure, and the degree of nitrogen substitution affected the complexation. Competition experiments and guest-exchange reactions indicated that the hydroxyl groups of guests participate in intermolecular hydrogen bonding with the glucocalixarene.

  11. Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation

    International Nuclear Information System (INIS)

    Concha S, K.; Avila, O.; Gamboa de Buen, I.; Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E.

    2004-01-01

    The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of 60 Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E 1 energy (4.8 MeV) and E 2 (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

  12. Atom probe field ion microscopy and related topics: A bibliography 1993

    International Nuclear Information System (INIS)

    Godfrey, R.D.; Miller, M.K.; Russell, K.F.

    1994-10-01

    This bibliography, covering the period 1993, includes references related to the following topics: atom probe field ion microscopy (APFIM), field emission (FE), and field ion microscopy (FIM). Technique-oriented studies and applications are included. The references contained in this document were compiled from a variety of sources including computer searches and personal lists of publications. To reduce the length of this document, the references have been reduced to the minimum necessary to locate the articles. The references are listed alphabetically by authors, an Addendum of references missed in previous bibliographies is included

  13. Workshop report of problems relating to multi-electron excited ions in plasma

    International Nuclear Information System (INIS)

    Fujimoto, Takashi; Suzuki, Hiroshi; Takayanagi, Toshinobu; Koike, Fumihiro; Nakamura, Koji.

    1979-08-01

    A workshop was held to discuss the problems relating to multiple electron-excited ions in plasma. The first part of this report deals with the problems of satellite lines. The satellite lines from laser plasma and vacuum sparks are discussed. Review papers on satellite lines and bielectronic recombination are also presented. The second part of this report deals with the problems of autoionization. Theory, comment on the compound state, observation of autoionization and resonance scattering, excitation cross-section, inner shell ionization, excitation through autoionization, and the bielectronic recombination of helium-like ions are discussed. (Kato, T.)

  14. Relation between the conditions of helium ion implantation and helium void equilibrium parameters

    International Nuclear Information System (INIS)

    Neklyudov, I.M.; Rybalko, V.F.; Ruzhitskij, V.V.; Tolstolutskaya, G.D.

    1981-01-01

    The conditions of helium thermodynamic equilibrium in a system of voids produced by helium ion bombardment of a metal sample are studied. As an initial equation for description of the equilibrium the Clapeyron equation was used. The equation is obtained relating basic parameters of helium voids (average diameter and density) to irradiation parameters (dose, ion energy (straggling)) and properties of the metal (surface tension coefficient, yield strength). Comparison of the calculations with experimental data on helium in nickel found in literature shows that the equation yields satisfactory resutls for the dose range 1.10 16 -1x10 17 cm -2 and temperatures T [ru

  15. Susceptible genes and molecular pathways related to heavy ion irradiation in oral squamous cell carcinoma cells

    International Nuclear Information System (INIS)

    Fushimi, Kazuaki; Uzawa, Katsuhiro; Ishigami, Takashi; Yamamoto, Nobuharu; Kawata, Tetsuya; Shibahara, Takahiko; Ito, Hisao; Mizoe, Jun-etsu; Tsujii, Hirohiko; Tanzawa, Hideki

    2008-01-01

    Background and purpose: Heavy ion beams are high linear energy transfer (LET) radiation characterized by a higher relative biologic effectiveness than low LET radiation. The aim of the current study was to determine the difference of gene expression between heavy ion beams and X-rays in oral squamous cell carcinoma (OSCC)-derived cells. Materials and methods: The OSCC cells were irradiated with accelerated carbon or neon ion irradiation or X-rays using three different doses. We sought to identify genes the expression of which is affected by carbon and neon ion irradiation using Affymetrix GeneChip analysis. The identified genes were analyzed using the Ingenuity Pathway Analysis Tool to investigate the functional network and gene ontology. Changes in mRNA expression in the genes were assessed by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Results: The microarray analysis identified 84 genes that were modulated by carbon and neon ion irradiation at all doses in OSCC cells. Among the genes, three genes (TGFBR2, SMURF2, and BMP7) and two genes (CCND1 and E2F3), respectively, were found to be involved in the transforming growth factor β-signaling pathway and cell cycle:G1/S checkpoint regulation pathway. The qRT-PCR data from the five genes after heavy ion irradiation were consistent with the microarray data (P < 0.01). Conclusion: Our findings should serve as a basis for global characterization of radiation-regulated genes and pathways in heavy ion-irradiated OSCC

  16. The alteration of oxidation and related properties of metals by ion implantation

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1981-01-01

    A review is given of the various ways in which ion implanted additives can affect the thermal oxidation of metals, for example by blocking diffusion paths for ions, by catalytic effects or by altering the plasticity of the oxide. The versatility of the process has already proved useful in the study of oxidation mechanisms. Ways of achieving a long-lasting protection are discussed in relation to the dominant mechanisms of oxidation inhibition. In many practical applications at elevated temperatures oxidation and mechanical stresses co-exist. In steels the process of oxidative wear is important under conditions of poor lubrication and implanted metallic ions have been shown to be effective. In titanium alloys fatigue cracks probably initiate at dislocation sites at which oxidation proceeds most rapidly, and hence the same implanted species can improve both types of behaviour. Successful implantation treatments for fretting fatigue in titanium and a corrosion-erosion problem in steel are described. (orig.)

  17. Relative ion yields in mammalian cell components using C60 SIMS

    Science.gov (United States)

    Keskin, Selda; Piwowar, Alan; Hue, Jonathan; Shen, Kan; Winograd, Nicholas

    2013-01-01

    Time of flight secondary ion mass spectrometry has been used to better understand the influence of molecular environment on the relative ion yields of membrane lipid molecules found in high abundance in a model mammalian cell line, RAW264.7. Control lipid mixtures were prepared to simulate lipid–lipid interactions in the inner and outer leaflet of cell membranes. Compared with its pure film, the molecular ion yields of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine are suppressed when mixed with 2-dipalmitoyl-sn-glycero-3-phosphocholine. In the mixture, proton competition between 1,2-dioleoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, and 2-dipalmitoyl-sn-glycero-3-phosphocholine led to lower ionization efficiency. The possible mechanism for ion suppression was also investigated with 1H and 13C nuclear magnetic resonance spectroscopy. The formation of a hydroxyl bond in lipid mixtures confirms the mechanism involving proton exchange with the surrounding environment. Similar effects were observed for lipid mixtures mimicking the composition of the inner leaflet of cell membranes. The secondary molecular ion yield of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine was observed to be enhanced in the presence of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine. PMID:25140069

  18. Relative Free Energies for Hydration of Monovalent Ions from QM and QM/MM Simulations.

    Science.gov (United States)

    Lev, Bogdan; Roux, Benoît; Noskov, Sergei Yu

    2013-09-10

    Methods directly evaluating the hydration structure and thermodynamics of physiologically relevant cations (Na(+), K(+), Cl(-), etc.) have wide ranging applications in the fields of inorganic, physical, and biological chemistry. All-atom simulations based on accurate potential energy surfaces appear to offer a viable option for assessing the chemistry of ion solvation. Although MD and free energy simulations of ion solvation with classical force fields have proven their usefulness, a number of challenges still remain. One of them is the difficulty of force field benchmarking and validation against structural and thermodynamic data obtained for a condensed phase. Hybrid quantum mechanical/molecular mechanical (QM/MM) models combined with sampling algorithms have the potential to provide an accurate solvation model and to incorporate the effects from the surrounding, which is often missing in gas-phase ab initio computations. Herein, we report the results from QM/MM free energy simulations of Na(+)/K(+) and Cl(-)/Br(-) hydration where we simultaneously characterized the relative thermodynamics of ion solvation and changes in the solvation structure. The Flexible Inner Region Ensemble Separator (FIRES) method was used to impose a spatial separation between QM region and the outer sphere of solvent molecules treated with the CHARMM27 force field. FEP calculations based on QM/MM simulations utilizing the CHARMM/deMon2k interface were performed with different basis set combinations for K(+)/Na(+) and Cl(-)/Br(-) perturbations to establish the dependence of the computed free energies on the basis set level. The dependence of the computed relative free energies on the size of the QM and MM regions is discussed. The current methodology offers an accurate description of structural and thermodynamic aspects of the hydration of alkali and halide ions in neat solvents and can be used to obtain thermodynamic data on ion solvation in condensed phase along with underlying

  19. Dispersion relations of density fluctuations observed by heavy ion beam probe in the TEXT tokamak

    International Nuclear Information System (INIS)

    Ross, D.W.

    1990-09-01

    Wave numbers as functions of frequency for density fluctuations in the core of the TEXT tokamak are measured in Heavy Ion Beam Probe experiments by analyzing the relative phases of signals originating from nearby points in the plasma. The adjacent points are typically 2 cm apart, with their relative orientation (δr, δθ) depending on position (r,θ). for angular frequencies ω ≤ 10 6 /s the signals are quite coherent, leading to reasonably well-defined ''dispersion relations.'' These do not correspond to known modes of the drift wave type, i.e., ballooning or slab-like electron drift waves or ion temperature gradient modes. The effect of finite sample volume size does not significantly alter this conclusion. 25 refs., 6 figs., 3 tabs

  20. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne

    2017-09-27

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  1. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne; Schilling, Rhiannon K.; Berger, Bettina; Garcia, Alexandre F.; Trittermann, Christine; Coventry, Stewart; Rabie, Huwaida; Brien, Chris; Nguyen, Martin; Tester, Mark A.; Roy, Stuart J.

    2017-01-01

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  2. Gyro-viscosity and linear dispersion relations in pair-ion magnetized plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Kono, M. [Faculty of Policy Studies, Chuo University, Tokyo 192-0393 (Japan); Vranjes, J. [Instituto de Astrofisica de Canarias, Tenerife E38205 (Spain); Departamento de Astrofisica, Universidad de La Laguna, Tenerife E38205 (Spain)

    2015-11-15

    A fluid theory has been developed by taking account of gyro-viscosity to study wave propagation characteristics in a homogeneous pair-ion magnetized plasma with a cylindrical symmetry. The exact dispersion relations derived by the Hankel-Fourier transformation are shown comparable with those observed in the experiment by Oohara and co-workers. The gyro-viscosity is responsible for the change in propagation characteristics of the ion cyclotron wave from forward to backward by suppressing the effect of the thermal pressure which normally causes the forward nature of dispersion. Although the experiment has been already explained by a kinetic theory by the present authors, the kinetic derivations are so involved because of exact particle orbits in phase space, finite Lamor radius effects, and higher order ion cyclotron resonances. The present fluid theory provides a simple and transparent structure to the dispersion relations since the gyro-viscosity is renormalized into the ion cyclotron frequency which itself indicates the backward nature of dispersion. The usual disadvantage of a fluid theory, which treats only fundamental modes of eigen-waves excited in a system and is not able to describe higher harmonics that a kinetic theory does, is compensated by simple derivations and clear picture based on the renormalization of the gyro-viscosity.

  3. Damage related deep electron levels in ion implanted GaAs

    International Nuclear Information System (INIS)

    Allsopp, D.W.E.; Peaker, A.R.

    1986-01-01

    A study has been made of the deep electron levels in semi-insulating GaAs implanted with either 78 Se + or 29 Si + ions and rendered n-type by subsequent annealing without encapsulation in partial pressures of arsenic or arsine. Three implantation related deep states were detected with concentration profiles approximating to the type of Gaussian distributions expected for point defects related to ion implantation damage. Further heat treatment of the samples at 500 0 C in a gas ambient of U 2 /H 2 substantially reduced concentration of these deep levels. Two of these states were thought to be related to displacements of the substrate atoms. The third, at Esubc -0.67 eV, was found in only 78 Se + ion implanted GaAs substrates and was thought to be a defect involving both Se and As atoms, rather than intrinsic lattice disorder. It is proposed that the annealing rate of these implantation related deep levels depends crucially on the in-diffusion of arsenic vacancies during heat treatments. (author)

  4. Comprehensive Peptide Ion Structure Studies Using Ion Mobility Techniques: Part 3. Relating Solution-Phase to Gas-Phase Structures.

    Science.gov (United States)

    Kondalaji, Samaneh Ghassabi; Khakinejad, Mahdiar; Valentine, Stephen J

    2018-06-01

    Molecular dynamics (MD) simulations have been utilized to study peptide ion conformer establishment during the electrospray process. An explicit water model is used for nanodroplets containing a model peptide and hydronium ions. Simulations are conducted at 300 K for two different peptide ion charge configurations and for droplets containing varying numbers of hydronium ions. For all conditions, modeling has been performed until production of the gas-phase ions and the resultant conformers have been compared to proposed gas-phase structures. The latter species were obtained from previous studies in which in silico candidate structures were filtered according to ion mobility and hydrogen-deuterium exchange (HDX) reactivity matches. Results from the present study present three key findings namely (1) the evidence from ion production modeling supports previous structure refinement studies based on mobility and HDX reactivity matching, (2) the modeling of the electrospray process is significantly improved by utilizing initial droplets existing below but close to the calculated Rayleigh limit, and (3) peptide ions in the nanodroplets sample significantly different conformers than those in the bulk solution due to altered physicochemical properties of the solvent. Graphical Abstract ᅟ.

  5. Rotation driven translational diffusion of polyatomic ions in water: A novel mechanism for breakdown of Stokes-Einstein relation

    Science.gov (United States)

    Banerjee, Puja; Yashonath, Subramanian; Bagchi, Biman

    2017-04-01

    While most of the existing theoretical and simulation studies have focused on simple, spherical, halide and alkali ions, many chemically, biologically, and industrially relevant electrolytes involve complex non-spherical polyatomic ions like nitrate, chlorate, and sulfate to name only a few. Interestingly, some polyatomic ions in spite of being larger in size show anomalously high diffusivity and therefore cause a breakdown of the venerable Stokes-Einstein (S-E) relation between the size and diffusivity. Here we report a detailed analysis of the dynamics of anions in aqueous potassium nitrate (KNO3) and aqueous potassium acetate (CH3COOK) solutions. The two ions, nitrate (-NO3) and acetate (CH3-CO2 ), with their similar size show a large difference in diffusivity values. We present evidence that the translational motion of these polyatomic ions is coupled to the rotational motion of the ion. We show that unlike the acetate ion, nitrate ion with a symmetric charge distribution among all periphery oxygen atoms shows a faster rotational motion with large amplitude rotational jumps which enhances its translational motion due to translational-rotational coupling. By creating a family of modified-charge model systems, we have analysed the rotational motion of asymmetric polyatomic ions and the contribution of it to the translational motion. These model systems help clarifying and establishing the relative contribution of rotational motion in enhancing the diffusivity of the nitrate ion over the value predicted by the S-E relation and also over the other polyatomic ions having asymmetric charge distribution like the acetate ion. In the latter case, reduced rotational motion results in lower diffusivity values than those with symmetric charge distribution. We propose translational-rotational coupling as a general mechanism of the breakdown of the S-E relation in the case of polyatomic ions.

  6. InternatIonalIzatIon or natIonalIzatIon by CommunICatIon? the InternatIonal CommunICatIon relatIons of the German suffraGe movement

    OpenAIRE

    Kinnebrock, Susanne

    2011-01-01

    The women’s movements of the late nineteenth and early twentieth century were closely connected by a network of manifold communication relations. To analyze the development of social movements and their transnational communication in a systematic way this article presents an analytical framework and then applies it to the German suffrage movement. Considering different stages of domestic social movements (initial phase, organizational phase, phase of establishment) and different types of medi...

  7. Quantification of the Relative Biological Effectiveness for Ion Beam Radiotherapy: Direct Experimental Comparison of Proton and Carbon Ion Beams and a Novel Approach for Treatment Planning

    International Nuclear Information System (INIS)

    Elsaesser, Thilo; Weyrather, Wilma K.; Friedrich, Thomas; Durante, Marco; Iancu, Gheorghe; Kraemer, Michael; Kragl, Gabriele; Brons, Stephan; Winter, Marcus; Weber, Klaus-Josef; Scholz, Michael

    2010-01-01

    Purpose: To present the first direct experimental in vitro comparison of the biological effectiveness of range-equivalent protons and carbon ion beams for Chinese hamster ovary cells exposed in a three-dimensional phantom using a pencil beam scanning technique and to compare the experimental data with a novel biophysical model. Methods and Materials: Cell survival was measured in the phantom after irradiation with two opposing fields, thus mimicking the typical patient treatment scenario. The novel biophysical model represents a substantial extension of the local effect model, previously used for treatment planning in carbon ion therapy for more than 400 patients, and potentially can be used to predict effectiveness of all ion species relevant for radiotherapy. A key feature of the new approach is the more sophisticated consideration of spatially correlated damage induced by ion irradiation. Results: The experimental data obtained for Chinese hamster ovary cells clearly demonstrate that higher cell killing is achieved in the target region with carbon ions as compared with protons when the effects in the entrance channel are comparable. The model predictions demonstrate agreement with these experimental data and with data obtained with helium ions under similar conditions. Good agreement is also achieved with relative biological effectiveness values reported in the literature for other cell lines for monoenergetic proton, helium, and carbon ions. Conclusion: Both the experimental data and the new modeling approach are supportive of the advantages of carbon ions as compared with protons for treatment-like field configurations. Because the model predicts the effectiveness for several ion species with similar accuracy, it represents a powerful tool for further optimization and utilization of the potential of ion beams in tumor therapy.

  8. Relation between the ion size and pore size for an electric double-layer capacitor.

    Science.gov (United States)

    Largeot, Celine; Portet, Cristelle; Chmiola, John; Taberna, Pierre-Louis; Gogotsi, Yury; Simon, Patrice

    2008-03-05

    The research on electrochemical double layer capacitors (EDLC), also known as supercapacitors or ultracapacitors, is quickly expanding because their power delivery performance fills the gap between dielectric capacitors and traditional batteries. However, many fundamental questions, such as the relations between the pore size of carbon electrodes, ion size of the electrolyte, and the capacitance have not yet been fully answered. We show that the pore size leading to the maximum double-layer capacitance of a TiC-derived carbon electrode in a solvent-free ethyl-methylimmidazolium-bis(trifluoro-methane-sulfonyl)imide (EMI-TFSI) ionic liquid is roughly equal to the ion size (approximately 0.7 nm). The capacitance values of TiC-CDC produced at 500 degrees C are more than 160 F/g and 85 F/cm(3) at 60 degrees C, while standard activated carbons with larger pores and a broader pore size distribution present capacitance values lower than 100 F/g and 50 F/cm(3) in ionic liquids. A significant drop in capacitance has been observed in pores that were larger or smaller than the ion size by just an angstrom, suggesting that the pore size must be tuned with sub-angstrom accuracy when selecting a carbon/ion couple. This work suggests a general approach to EDLC design leading to the maximum energy density, which has been now proved for both solvated organic salts and solvent-free liquid electrolytes.

  9. Dispersion relation approach to sub-barrier heavy ion fusion reactions

    International Nuclear Information System (INIS)

    Franzin, V.L.M.; Hussein, M.S.

    1986-07-01

    With the aid of an inverse dispersion relation, which gives the imaginary part of the fusion inclusive polarization potential (IPP) in terms of the principal part integral involving the real part of the IPP, the sub-barrier fusion of heavy ions is discussed. The system 16 O+ A Sm is taken as an example. The reactive content of the extracted IPP is analysed within the coupled channels theory. (Author) [pt

  10. A simple theoretical approach to determine relative ion yield (RIY) in glow discharge mass spectrometry (GDMS)

    Energy Technology Data Exchange (ETDEWEB)

    Born, Sabine [Degussa AG, Hanau (Germany); Matsunami, Noriaki [Nagoya Univ. (Japan). Faculty of Engineering; Tawara, Hiroyuki [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2000-01-01

    Direct current glow discharge mass spectrometry (dc-GDMS) has been applied to detect impurities in metals. The aim of this study is to understand quantitatively the processes taking place in GDMS and establish a model to calculate the relative ion yield (RIY), which is inversely proportional to the relative sensitivity factor (RSF), in order to achieve better agreement between the calculated and the experimental RIYs. A comparison is made between the calculated RIY of the present model and the experimental RIY, and also with other models. (author)

  11. Ion irradiation-induced diffusion in bixbyite-fluorite related oxides: Dislocations and phase transformation

    Energy Technology Data Exchange (ETDEWEB)

    Rolly, Gaboriaud, E-mail: Rolly.gaboriaud@univ-poitiers.fr [Institut Pprime, CNRS-University of Poitiers, SP2MI-BP 30179, 86962 Chasseneuil-Futuroscope (France); Fabien, Paumier [Institut Pprime, CNRS-University of Poitiers, SP2MI-BP 30179, 86962 Chasseneuil-Futuroscope (France); Bertrand, Lacroix [CSIC – University of Sevilla, Avenida Américo Vespucio, 49, 41092 Sevilla (Spain)

    2014-05-01

    Ion-irradiation induced diffusion and the phase transformation of a bixbyite-fluorite related rare earth oxide thin films are studied. This work is focused on yttrium sesquioxide, Y{sub 2}O{sub 3}, thin films deposited on Si (1 0 0) substrates using the ion beam sputtering technique (IBS). As-deposited samples were annealed ant then irradiated at cryogenic temperature (80 K) with 260 keV Xe{sup 2+} at different fluences. The irradiated thin oxide films are characterized by X-ray diffraction. A cubic to monoclinic phase transformation was observed. Analysis of this phenomenon is done in terms of residual stresses. Stress measurements as a function of irradiation fluences were realised using the XRD-sin{sup 2}ψ method. Stress evolution and kinetic of the phase transformation are compared and leads to the role-played by the nucleation of point and extended defects.

  12. Oxidative damage to collagen and related substrates by metal ion/hydrogen peroxide systems

    DEFF Research Database (Denmark)

    Hawkins, C L; Davies, Michael Jonathan

    1997-01-01

    . In this study electron paramagnetic resonance spectroscopy with spin trapping has been used to identify radicals formed on collagen and related materials by metal ion-H2O2 mixtures. Attack of the hydroxyl radical, from a Fe(II)-H2O2 redox couple, on collagen peptides gave signals from both side chain (.CHR...... are similar to those from the alpha-carbon site of peptides and the side-chain of lysine. Enzymatic digestion of the large, protein-derived, species releases similar low-molecular-weight adducts. The metal ion employed has a dramatic effect on the species observed. With Cu(I)-H2O2 or Cu(II)-H2O2 instead of Fe(II)-H......2O2, evidence has been obtained for: i) altered sites of attack and fragmentation, ii) C-terminal decarboxylation, and iii) hydrogen abstraction at N-terminal alpha-carbon sites. This altered behaviour is believed to be due to the binding of copper ions to some substrates and hence site...

  13. Linear and nonlinear physics of the magnetoacoustic cyclotron instability of fusion-born ions in relation to ion cyclotron emission

    Energy Technology Data Exchange (ETDEWEB)

    Carbajal, L., E-mail: L.Carbajal-Gomez@warwick.ac.uk; Cook, J. W. S. [Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Dendy, R. O. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB, Oxfordshire (United Kingdom); Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Chapman, S. C. [Centre for Fusion, Space and Astrophysics, Department of Physics, The University of Warwick, Coventry CV4 7AL (United Kingdom); Department of Mathematics and Statistics, University of Tromsø, N-9037, Tromsø (Norway); Max Planck Institute for the Physics of Complex Systems, D-01187, Dresden (Germany)

    2014-01-15

    The magnetoacoustic cyclotron instability (MCI) probably underlies observations of ion cyclotron emission (ICE) from energetic ion populations in tokamak plasmas, including fusion-born alpha-particles in JET and TFTR [Dendy et al., Nucl. Fusion 35, 1733 (1995)]. ICE is a potential diagnostic for lost alpha-particles in ITER; furthermore, the MCI is representative of a class of collective instabilities, which may result in the partial channelling of the free energy of energetic ions into radiation, and away from collisional heating of the plasma. Deep understanding of the MCI is thus of substantial practical interest for fusion, and the hybrid approximation for the plasma, where ions are treated as particles and electrons as a neutralising massless fluid, offers an attractive way forward. The hybrid simulations presented here access MCI physics that arises on timescales longer than can be addressed by fully kinetic particle-in-cell simulations and by analytical linear theory, which the present simulations largely corroborate. Our results go further than previous studies by entering into the nonlinear stage of the MCI, which shows novel features. These include stronger drive at low cyclotron harmonics, the re-energisation of the alpha-particle population, self-modulation of the phase shift between the electrostatic and electromagnetic components, and coupling between low and high frequency modes of the excited electromagnetic field.

  14. Experimental Verification of a Jarzynski-Related Information-Theoretic Equality by a Single Trapped Ion.

    Science.gov (United States)

    Xiong, T P; Yan, L L; Zhou, F; Rehan, K; Liang, D F; Chen, L; Yang, W L; Ma, Z H; Feng, M; Vedral, V

    2018-01-05

    Most nonequilibrium processes in thermodynamics are quantified only by inequalities; however, the Jarzynski relation presents a remarkably simple and general equality relating nonequilibrium quantities with the equilibrium free energy, and this equality holds in both the classical and quantum regimes. We report a single-spin test and confirmation of the Jarzynski relation in the quantum regime using a single ultracold ^{40}Ca^{+} ion trapped in a harmonic potential, based on a general information-theoretic equality for a temporal evolution of the system sandwiched between two projective measurements. By considering both initially pure and mixed states, respectively, we verify, in an exact and fundamental fashion, the nonequilibrium quantum thermodynamics relevant to the mutual information and Jarzynski equality.

  15. Multi-dimensional TOF-SIMS analysis for effective profiling of disease-related ions from the tissue surface.

    Science.gov (United States)

    Park, Ji-Won; Jeong, Hyobin; Kang, Byeongsoo; Kim, Su Jin; Park, Sang Yoon; Kang, Sokbom; Kim, Hark Kyun; Choi, Joon Sig; Hwang, Daehee; Lee, Tae Geol

    2015-06-05

    Time-of-flight secondary ion mass spectrometry (TOF-SIMS) emerges as a promising tool to identify the ions (small molecules) indicative of disease states from the surface of patient tissues. In TOF-SIMS analysis, an enhanced ionization of surface molecules is critical to increase the number of detected ions. Several methods have been developed to enhance ionization capability. However, how these methods improve identification of disease-related ions has not been systematically explored. Here, we present a multi-dimensional SIMS (MD-SIMS) that combines conventional TOF-SIMS and metal-assisted SIMS (MetA-SIMS). Using this approach, we analyzed cancer and adjacent normal tissues first by TOF-SIMS and subsequently by MetA-SIMS. In total, TOF- and MetA-SIMS detected 632 and 959 ions, respectively. Among them, 426 were commonly detected by both methods, while 206 and 533 were detected uniquely by TOF- and MetA-SIMS, respectively. Of the 426 commonly detected ions, 250 increased in their intensities by MetA-SIMS, whereas 176 decreased. The integrated analysis of the ions detected by the two methods resulted in an increased number of discriminatory ions leading to an enhanced separation between cancer and normal tissues. Therefore, the results show that MD-SIMS can be a useful approach to provide a comprehensive list of discriminatory ions indicative of disease states.

  16. Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation; Eficiencias termoluminiscentes relativas de TLD-100 para iones de nitrogeno respecto de radiacion gamma

    Energy Technology Data Exchange (ETDEWEB)

    Concha S, K. [UNAM, Facultad de Ciencias, 04510 Mexico D.F. (Mexico); Avila, O. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Gamboa de Buen, I. [ICN-UNAM, 04510 Mexico D.F. (Mexico); Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E. [IFUNAM, 04510 Mexico D.F. (Mexico)

    2004-07-01

    The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of {sup 60} Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E{sub 1} energy (4.8 MeV) and E{sub 2} (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

  17. Lipophilicity of acetylcholine and related ions examined by ion transfer voltammetry at a polarized room-temperature ionic liquid membrane

    Czech Academy of Sciences Publication Activity Database

    Langmaier, Jan; Záliš, Stanislav; Samec, Zdeněk

    2018-01-01

    Roč. 815, APR 2018 (2018), s. 183-188 ISSN 1572-6657 R&D Projects: GA ČR(CZ) GA15-03139S; GA ČR(CZ) GA17-05387S Institutional support: RVO:61388955 Keywords : acetylcholine * choline * ion transfer voltammetry Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis) Impact factor: 3.012, year: 2016

  18. Health-related quality of life after carbon-ion radiotherapy for prostate cancer. A 3-year prospective study

    International Nuclear Information System (INIS)

    Katoh, Hiroyuki; Tsuji, Hiroshi; Ishikawa, Hitoshi

    2014-01-01

    To assess 3-year health-related quality of life of patients treated with carbon ion radiotherapy for prostate cancer. A total of 213 patients received carbon-ion radiotherapy at a total dose of 66 Gy equivalent in 20 fractions over 5 weeks, and neoadjuvant and adjuvant androgen deprivation therapy were administered for high-risk patients for at least 12 months. A health-related quality of life assessment was carried out at four time-points (immediately before the initiation of carbon-ion radiotherapy, immediately after, 12 and 36 months after completion of carbon-ion radiotherapy) using Functional Assessment of Cancer Therapy General and for Prostate Cancer Patients. The evaluable response rates among all responses were more than 94%. Overall, a significant decrease in the scores of the health-related quality of life 12 months after carbon-ion radiotherapy returned to their baseline levels at 36 months. Additionally, no significant decrease was observed in the scores at any of the assessment time-points compared with their baseline scores in the group of carbon-ion radiotherapy without androgen deprivation therapy; however, the presence of morbidity and biochemical failure significantly worsened the scores, and the decreases in the scores did not improve even at 36 months after carbon-ion radiotherapy. An assessment based on a subjective scoring system shows a significant decrease in health-related quality of life at 12 months after carbon-ion radiation therapy, which tends to return to baseline levels at 36 months. The presence of morbidity and bio-chemical failure significantly worsen health-related quality of life scores. Further controlled studies focusing on health-related quality of life assessment in patients with prostate cancer are warranted. (author)

  19. Atom probe field ion microscopy and related topics: A bibliography 1991

    International Nuclear Information System (INIS)

    Russell, K.F.; Miller, M.K.

    1993-01-01

    This report contains a bibliography for 1991 on the following topics: Atom probe field ion microscopy; field desorption mass spectrometry; field emission; field ion microscopy; and field emission theory

  20. Heavy-ion optical potential for sub-barrier fusion deduced from a dispersion relation

    International Nuclear Information System (INIS)

    Kim, B.T.; Kim, H.C.; Park, K.E.

    1988-01-01

    The heavy-ion energy-dependent optical potentials for the 16 O+ 208 Pb system are deduced from a dispersion relation. These potentials are used to analyze the elastic scattering, fusion, and spin distributions of compound nuclei for the system in a unified way based on the direct reaction theory. It turns out that the energy dependence of the optical potential is essential in explaining the data at near- and sub-barrier energies. The real part of the energy-dependent optical potential deduced was also used in calculating the elastic and fusion cross sections by the conventional barrier penetration model using an incoming wave boundary condition. The predictions of the elastic scattering, fusion cross sections, and the spin distributions of compound nuclei are not satisfactory compared with those from the direct reaction approach. It seems to originate from the fact that this model neglects absorption around the Coulomb barrier region

  1. Study on relations between heavy ions single event upset cross sections and γ accumulated doses

    International Nuclear Information System (INIS)

    He Chaohui; Geng Bin; Wang Yanping; Peng Honglun; Yang Hailiang; Chen Xiaohua; Li Guozheng

    2002-01-01

    Experiments were done under 252 Cf and 60 Co γ source to study the relation between heavy ion Single Event Upset (SEU) cross sections and γ accumulated doses. There was no obvious rule and little influence of γ accumulated doses on SEU cross sections when Static Random Access Memories were in power off mode and static power on mode. In active measuring mode, the SEU cross section increased as the accumulated doses increasing when same data were written in memory cells. If reverse data, such as '55' and 'AA', were written in memory cells during the experiment, the SEU cross sections decreased to the level when memories were not irradiated under 60 Co γ source, even more small. It implied that the influence of γ accumulated doses on SEU cross sections can be set off by this method

  2. In situ investigation of helium fuzz growth on tungsten in relation to ion flux, fluence, surface temperature and ion energy using infrared imaging in PSI-2

    International Nuclear Information System (INIS)

    Möller, S; Kachko, O; Rasinski, M; Kreter, A; Linsmeier, Ch

    2017-01-01

    Tungsten is a candidate material for plasma-facing components in nuclear fusion reactors. In operation it will face temperatures >800 K together with an influx of helium ions. Previously, the evolution of special surface nanostructures called fuzz was found under these conditions in a limited window of surface temperature, ion flux and ion energy. Fuzz potentially leads to lower heat load tolerances, enhanced erosion and dust formation, hence should be avoided in a fusion reactor. Here the fuzz growth is reinvestigated in situ during its growth by considering its impact on the surfaces infrared emissivity at 4 μ m wavelength with an infrared camera in the linear plasma device PSI-2. A hole in the surface serves as an emissivity reference to calibrate fuzz thickness versus infrared emissivity. Among new data on the above mentioned relations, a lower fuzz growth threshold of 815 ± 24 K is found. Fuzz is seen to grow on rough and polished surfaces and even on the hole’s side walls alike. Literature scalings for thickness, flux and time relations of the fuzz growth rate could not be reproduced, but for the temperature scaling a good agreement to the Arrhenius equation was found. (paper)

  3. Expression of biomineralization-related ion transport genes in Emiliania huxleyi.

    Science.gov (United States)

    Mackinder, Luke; Wheeler, Glen; Schroeder, Declan; von Dassow, Peter; Riebesell, Ulf; Brownlee, Colin

    2011-12-01

    Biomineralization in the marine phytoplankton Emiliania huxleyi is a stringently controlled intracellular process. The molecular basis of coccolith production is still relatively unknown although its importance in global biogeochemical cycles and varying sensitivity to increased pCO₂ levels has been well documented. This study looks into the role of several candidate Ca²⁺, H⁺ and inorganic carbon transport genes in E. huxleyi, using quantitative reverse transcriptase PCR. Differential gene expression analysis was investigated in two isogenic pairs of calcifying and non-calcifying strains of E. huxleyi and cultures grown at various Ca²⁺ concentrations to alter calcite production. We show that calcification correlated to the consistent upregulation of a putative HCO₃⁻ transporter belonging to the solute carrier 4 (SLC4) family, a Ca²⁺/H⁺ exchanger belonging to the CAX family of exchangers and a vacuolar H⁺-ATPase. We also show that the coccolith-associated protein, GPA is downregulated in calcifying cells. The data provide strong evidence that these genes play key roles in E. huxleyi biomineralization. Based on the gene expression data and the current literature a working model for biomineralization-related ion transport in coccolithophores is presented. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  4. Atom probe field ion microscopy and related topics: A bibliography 1992

    Energy Technology Data Exchange (ETDEWEB)

    Russell, K.F.; Godfrey, R.D.; Miller, M.K.

    1993-12-01

    This bibliography contains citations of books, conference proceedings, journals, and patents published in 1992 on the following types of microscopy: atom probe field ion microscopy (108 items); field emission microscopy (101 items); and field ion microscopy (48 items). An addendum of 34 items missed in previous bibliographies is included.

  5. Extended ion energetics data base for mass spectrometric characterization of energy related pollutants. Final report

    International Nuclear Information System (INIS)

    Parr, A.C.

    1983-01-01

    This project funded research at NBS from September, 1982 until November, 1983 and represented a continuation of an effort in precision ion thermochemistry measurements and calculations. The effort was divided into two main areas: laboratory effort using threshold photoelectron-photoion coincidence spectroscopy and a theoretical effort in ion energetics estimation schemes

  6. Range to cone length relations for light ions in CR-39

    International Nuclear Information System (INIS)

    Gil, L.R.; Marques, A.

    1988-01-01

    Curves ''range x cone lenght'' and ''diameter x cone lenght'' are calculated for tracks left by low energy light ions in CR-39. The calculations cover ions from helium to iron and are performed for 6.25 N NaOH at 70 0 C and a standard etching time but can be easily extended to other etching conditions. (author) [pt

  7. Changes in transcript related to osmosis and intracellular ion homeostasis in Paulownia tomentosa under salt stress

    Directory of Open Access Journals (Sweden)

    Guoqiang eFan

    2016-03-01

    Full Text Available Paulownia tomentosa is an important economic and greening tree species that is cultivated widely, including salt environment. Our previous studies indicated its autotetraploid induced by colchicine showed better stress tolerance, but the underlying molecular mechanism related to ploidy and salt stress is still unclear. To investigate this issue, physiological measurements and transcriptome profiling of diploid and autotetraploid plants untreated and treated with NaCl were performed. Through the comparisons among four accessions, for one thing, we found different physiological changes between diploid and autotetraploid P. tomentosa; for another, and we detected many differentially expressed unigenes involved in salt stress response. These differentially expressed unigenes were assigned to several metabolic pathways, including plant hormone signal transduction, RNA transporter, protein processing in endoplasmic reticulum and plant-pathogen interaction, which constructed the complex regulatory network to maintain osmotic and intracellular ion homeostasis. Quantitative real-time polymerase chain reaction was used to confirm the expression patterns of 20 unigenes. The results establish the foundation for the genetic basis of salt tolerance in P. tomentosa, which in turn accelerates Paulownia breeding and expands available arable land.

  8. Improvements in or relating to the deflection of ion beams by electrostatic mirror apparatus

    International Nuclear Information System (INIS)

    Freeman, J.H.

    1980-01-01

    An electrostatic mirror apparatus is described for the deflection of positive ion beams. It is claimed that with this apparatus, ion beams of intensity greater than 100 microamps in an electromagnetic separator have been turned through 90 0 and it has been observed that high beam currents can cause the ion beam to 'blow up' (i.e. expand) as it enters the mirror space and then be focused down on exit to a beam narrower than that incident upon the mirror apparatus. (U.K.)

  9. Dispersion relation and growth in a two-stream free electron laser with helical wiggler and ion channel guiding

    International Nuclear Information System (INIS)

    Mehdian, Hassan; Abbasi, Negar

    2008-01-01

    A linear theory of two-stream free electron laser (FEL) with helical wiggler and ion channel guiding is presented. The dispersion relation is obtained with the help of fluid theory and the growth rate is analyzed through the numerical solutions. The considerable enhancement of the growth rate is demonstrated due to the two-stream instability and continuous tuning of peak growth rate ratio, two-stream FEL compared to single-stream FEL, in terms of varying the ion channel frequency is illustrated

  10. Ion acoustic waves and related plasma observations in the solar wind

    International Nuclear Information System (INIS)

    Gurnett, D.A.; Marsch, E.; Pilipp, W.; Schwenn, R.; Rosenbauer, H.

    1979-01-01

    This paper presents an investigation of solar wind ion acoustic waves and their relationship to the macroscopic and microscopic characteristics of the solar wind plasma. Comparisons with the overall solar wind corotational structure show that the most intense ion acoustic waves usually occur in the low-velocity regions ahead of high-speed solar wind streams. Of the detailed plasma parameters investigated, the ion acoustic wave intensities are found to be most closely correlated with the electron to proton temperature ratio T/sub e//T/sub p/ and with the electron heat flux. Investigations of the detailed electron and proton distribution functions also show that the ion acoustic waves usually occur in regions with highly non-Maxwellian distributions characteristic of double-proton streams. The distribution functions for the double-proton streams are usually not resolved into two clearly defined peaks, but rather they appear as a broad shoulder on the main proton distribution. Two main mechanisms, an electron heat flux instability and a double-ion beam instability, are considered for generating the ion-acoustic-like waves observed in the solar wind. Both mechanisms have favorable and unfavorable features. The electron heat flux mechanism can account for the observed waves at moderate to large ratios of T/sub e//T/sub p/ but has problems when T/sub e//T/sub p/ is small, as sometimes occurs. The ion beam instability appears to provide more flexibility on the T/sub e//T/sub p/ ratio; however detailed comparisons using observed distribution functions indicate that the ion beam mode is usually stable. Possible resolutions of these difficulties are discussed

  11. Fusion-Related Ionization and Recombination Data for Tungsten Ions in Low to Moderately High Charge States

    Directory of Open Access Journals (Sweden)

    Alfred Müller

    2015-05-01

    Full Text Available Collisional processes and details of atomic structure of heavy many-electron atoms and ions are not yet understood in a fully satisfying manner. Experimental studies are required for guiding new theoretical approaches. In response to fusion-related needs for collisional and spectroscopic data on tungsten atoms in all charge states, a project has been initiated in which electron-impact and photon-induced ionization as well as photorecombination of Wq+ ions are studied. Cross sections and rate coefficients were determined for charge states q ranging from q = 1 to q = 5 for photoionization, for q = 1 up to q = 19 for electron-impact ionization and for q = 18 to q = 21 for electron-ion recombination. An overview, together with a critical assessment of the methods and results is provided.

  12. Uptake and translocation of labelled iodide ion in privet (Ligustrum vulgare L. ) as related to its defoliating activity

    Energy Technology Data Exchange (ETDEWEB)

    Marczynski, S; Jankiewicz, L S [Szkola Glowna Gospodarstwa Wiejskiego, Warsaw (Poland)

    1978-01-01

    The /sup 131/J/sup -/ ion applied as KJ solution to lanolin ring on the leaf moved quickly to other parts of the leaf, however, it was transported to the stem and axillary bud in small amount. The /sup 131/J/sup -/ ion from potassium iodide was absorbed very fast by privet (Ligustrum vulgare L.). By 45 min after treatment about half of the applied ion was absorbed. This result was also confirmed in field experiments with non labelled KJ with privet and with SpiraeaXbumalda cv. Froebelii during 2 year experiments. In the conditions of high air humidity (95% r.h.) much more K/sup 131/J was absorbed than at low air humidity (50% r.h.) at the same temperature (23/sup 0/). Also at a relatively high temperature (23/sup 0/) the uptake was more intensive than at a low temperature (4/sup 0/), at the same air humidity (95% r.h.).

  13. Calculations on displacement damage and its related parameters for heavy ion bombardment in reactor materials

    International Nuclear Information System (INIS)

    Sone, Kazuho; Shiraishi, Kensuke

    1975-04-01

    The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage. (auth.)

  14. Calculations on displacement damage and its related parameters for heavy ion bombardment in reactor materials

    Energy Technology Data Exchange (ETDEWEB)

    Sone, K; Shiraishi, K

    1975-04-01

    The depth distribution of displacement damage expressed in displacements per atom (DPA) in reactor materials such as Mo, Nb, V, Fe and Ni bombarded by energetic nitrogen, argon and self ions with incident energy below 2 MeV was calculated following the theory developed by Lindhard and co-workers for the partition of energy as an energetic ion slowing down. In this calculation, energy loss due to electron excitation was taken into account for the atomic collision cascade after the primary knock-on process. Some parameters indispensable for the calculation such as energy loss rate, damage efficiency, projected range and its straggling were tabulated as a function of incident ion energy of 20 keV to 2 MeV. The damage and parameters were also calculated for 2 MeV nickel ions bombarding Fe targets. In this case, the DPA value is of 40--75% overestimated in a calculation disregarding electronic energy loss for primary knock-on atoms. The formula proposed in this report is significant for calculations on displacement damage produced by heavy ion bombardment as a simulation of high fluence fast neutron damage.

  15. Relative Biological Effectiveness of HZE Fe Ions for Induction ofMicro-Nuclei at Low Doses

    Energy Technology Data Exchange (ETDEWEB)

    Groesser, Torsten; Chun, Eugene; Rydberg, Bjorn

    2007-01-16

    Dose-response curves for induction of micro-nuclei (MN) was measured in Chinese hamster V79 and xrs6 (Ku80-) cells and in human mammary epithelial MCF10A cells in the dose range of 0.05-1 Gy. The Chinese Hamster cells were exposed to 1 GeV/u Fe ions, 600 MeV/u Fe ions, and 300 MeV/u Fe ions (LETs of 151, 176 and 235 keV/{micro}m respectively) as well as with 320 kVp X-rays as reference. Second-order polynomials were fitted to the induction curves and the initial slopes (the alpha values) were used to calculate RBE. For the repair proficient V79 cells the RBE at these low doses increased with LET. The values obtained were 3.1 (LET=151 keV/{micro}m), 4.3 (LET = 176 keV/{micro}m) and 5.7 (LET = 235 keV/{micro}m), while the RBE was close to 1 for the repair deficient xrs6 cells regardless of LET. For the MCF10A cells the RBE was determined for 1 GeV/u Fe ions and found to be 5.4, slightly higher than for V79 cells. To test the effect of shielding, the 1 GeV/u Fe ion beam was intercepted by various thickness of high-density polyethylene plastic absorbers, which resulted in energy loss and fragmentation. It was found that the MN yield for V79 cells placed behind the absorbers decreased in proportion to the decrease in dose both before and after the Fe ion Bragg peak (excluding the area around the Fe-ion Bragg peak itself), indicating that RBE did not change significantly due to shielding. At the Bragg peak the effectiveness for MN formation per unit dose was decreased, indicating an 'overkill' effect by low-energy very high-LET Fe ions.

  16. Charge-state related effects in sputtering of LiF by swift heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Assmann, W. [Ludwig-Maximilians-Universität München, 85748 Garching (Germany); Ban-d' Etat, B. [Centre de Recherche sur les Ions, les Matériaux et la photonique, CIMAP-GANIL, CEA–CNRS–ENSICAEN–Univ. Caen, 14070 Caen (France); Bender, M. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Boduch, P. [Centre de Recherche sur les Ions, les Matériaux et la photonique, CIMAP-GANIL, CEA–CNRS–ENSICAEN–Univ. Caen, 14070 Caen (France); Grande, P.L. [Univ. Fed. Rio Grande do Sul, BR-91501970 Porto Alegre, RS (Brazil); Lebius, H.; Lelièvre, D. [Centre de Recherche sur les Ions, les Matériaux et la photonique, CIMAP-GANIL, CEA–CNRS–ENSICAEN–Univ. Caen, 14070 Caen (France); Marmitt, G.G. [Univ. Fed. Rio Grande do Sul, BR-91501970 Porto Alegre, RS (Brazil); Rothard, H. [Centre de Recherche sur les Ions, les Matériaux et la photonique, CIMAP-GANIL, CEA–CNRS–ENSICAEN–Univ. Caen, 14070 Caen (France); Seidl, T.; Severin, D.; Voss, K.-O. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Toulemonde, M., E-mail: toulemonde@ganil.fr [Centre de Recherche sur les Ions, les Matériaux et la photonique, CIMAP-GANIL, CEA–CNRS–ENSICAEN–Univ. Caen, 14070 Caen (France); Trautmann, C. [GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt (Germany); Technische Universität Darmstadt, 64289 Darmstadt (Germany)

    2017-02-01

    Sputtering experiments with swift heavy ions in the electronic energy loss regime were performed by using the catcher technique in combination with elastic recoil detection analysis. The angular distribution of particles sputtered from the surface of LiF single crystals is composed of a jet-like peak superimposed on a broad isotropic distribution. By using incident ions of fixed energy but different charges states, the influence of the electronic energy loss on both components is probed. We find indications that isotropic sputtering originates from near-surface layers, whereas the jet component may be affected by contributions from depth up to about 150 nm.

  17. Relations Between Morphology and Catalytic Activity of Ion Exchanger Catalysts for Synthesis of Bisphenol A

    Czech Academy of Sciences Publication Activity Database

    Jeřábek, Karel; Hanková, Libuše; Prokop, Zdeněk; Lundquist, E. G.

    2002-01-01

    Roč. 232, 1-2 (2002), s. 181-188 ISSN 0926-860X R&D Projects: GA ČR GA104/99/0125 Keywords : ion exchangers * catalyst * morphology Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.915, year: 2002

  18. Stopping power and range relations for low and high Z ions in solids: a critical analysis

    International Nuclear Information System (INIS)

    Virk, H.S.; Randhawa, G.S.

    1997-01-01

    A critical analysis of various stopping power and range formulations has been made by comparing the calculated stopping power and range values with corresponding experimental values for different low Z (1≤Z≤8) and high Z projectiles (54≤Z≤92) in different targets, e.g. Be, C, Al, Au, Pb, CR-39, Lexan, Mylar, LR-115, CH, (CH)n, TRIFOL-TN, etc. atvarious low and high energies. A comparative study has been made by taking into consideration different target and projectile combinations, e.g., heavy ion-light target, light ion-heavy target and light ion -light target etc., Overall the Ziegler formulation (TRIM-95) provides the best agreement with the experimental results for all projectile and target combinations except for heavy ion-light target combination where it underestimates the stopping power data and overestimates the range data in the range, 2-50 MeV/u. Mukherjee and Nayak formulation totally fails at relativistic and low energies of the projectile, irrespective of the projectile-target combination. Northcliffe and Schilling formulation does not show any particular trend. Benton and Henke formulation gives good agreement between experimental and theoretical data within the range of experimental errors. (orig.)

  19. Use of heavy ion accelerators in fusion reactor-related radiation-damage studies

    International Nuclear Information System (INIS)

    Taylor, A.; Dobson, D.A.

    1974-01-01

    The heavy-ion accelerator has become an important tool in the study of the fundamentals of radiation damage in fission- and fusion-reactor materials. Present facilities for such studies within the Materials Science Division at Argonne National Laboratory are provided by two complementary accelerator systems. Examples of the work carried out are discussed

  20. Relating the 3D electrode morphology to Li-ion battery performance; a case for LiFePO4

    Science.gov (United States)

    Liu, Zhao; Verhallen, Tomas W.; Singh, Deepak P.; Wang, Hongqian; Wagemaker, Marnix; Barnett, Scott

    2016-08-01

    One of the main goals in lithium ion battery electrode design is to increase the power density. This requires insight in the relation between the complex heterogeneous microstructure existing of active material, conductive additive and electrolyte providing the required electronic and Li-ion transport. FIB-SEM is used to determine the three phase 3D morphology, and Li-ion concentration profiles obtained with Neutron Depth Profiling (NDP) are compared for two cases, conventional LiFePO4 electrodes and better performing carbonate templated LiFePO4 electrodes. This provides detailed understanding of the impact of key parameters such as the tortuosity for electron and Li-ion transport though the electrodes. The created hierarchical pore network of the templated electrodes, containing micron sized pores, appears to be effective only at high rate charge where electrolyte depletion is hindering fast discharge. Surprisingly the carbonate templating method results in a better electronic conductive CB network, enhancing the activity of LiFePO4 near the electrolyte-electrode interface as directly observed with NDP, which in a large part is responsible for the improved rate performance both during charge and discharge. The results demonstrate that standard electrodes have a far from optimal charge transport network and that significantly improved electrode performance should be possible by engineering the microstructure.

  1. Preparation of Fe{sub 3}O{sub 4}/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaolong; Liu Guoqiang; Yan Wei [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Yeung, Kelvin W.K. [Division of Spine Surgery, Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam (Hong Kong); Wu Shuilin; Yi Changfeng [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Division of Spine Surgery, Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam (Hong Kong); Xu Zushun, E-mail: zushun25@yahoo.com.cn [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Division of Spine Surgery, Department of Orthopaedics and Traumatology, University of Hong Kong, Pokfulam (Hong Kong)

    2012-04-15

    Cationic magnetic polymer particles Fe{sub 3}O{sub 4}/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe{sub 3}O{sub 4}, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier. - Highlights: Black-Right-Pointing-Pointer A new type of cationic magnetic polymer particles was synthesized by emulsifier-free emulsion polymerization. Black-Right-Pointing-Pointer Structural, morphological, and magnetic properties of the composite were evaluated. Black-Right-Pointing-Pointer The interaction between cationic magnetic polymer particles with DNA was confirmed by zeta potential measurements. Black-Right-Pointing-Pointer UV-vis spectrophotometry, fluorescent spectroscopy and agarose gel electrophoresis. Black-Right-Pointing-Pointer This process may have potential applications to gene carrier and DNA separation.

  2. Imaging properties of scintillators for heavy-ion-beams and related model calculations

    International Nuclear Information System (INIS)

    Guetlich, Eiko

    2011-08-01

    This thesis is treating the imaging properties of scintillating screens for high-current ion beams as delivered by the UNILAC at the GSI Helmholtzzentrum fuer Schwerionenforschung in Darmstadt, Germany. Scintillating screens are mainly used to measure and rate the tansversal beam parameters in nearly every particle accelerator. During daily operation, scintillating screens can be used to determine and optimize the position of the beam inside the beam-pipe as well as the transversal intensity distribution. Although scintillating screens are widely used in many measurement systems, their imaging properties are not well characterized. Within the framework of this thesis, accelerator based experiments were planed and carried out which allowed to compare the results of beam profile measurements of the different materials with reference methods. Parameters such as the screen temperature and particle energies have been varied. Additionaly, possible image distortions within the optical system have been investigated. To determine the influence of the emission spectra of the screens onto the profile measurement a novel experimental setup for the spectroscopic investigations has been established. The setup allows to investigate the emission spectrum along one spatial axes on the beamspot. The investigations focus on ceramic materials such as zirconium oxide doped e.g. with Mg (ZrO 2 :Mg) or aluminium oxide (Al 2 O 3 ). The materials have been irradiated with different ion species (e.g. Calcium and Uranium) with kinetic energies of 4.8 MeV/u (10% c) and 11.4 MeV (15% c). The results for different parameters are discussed and interpreted. The measured beam profiles show dependences of four parameters: - The material itself. - The screen temperature. - The accumulated fluence [ (Ions)/(cm 2 )]. - The excitation density [(Electron-Hole-Pairs)/(cm 3 )], which is proportional to the dose rate [(J)/(kg . s)] within the volume element. Among the above, the last one depends on the

  3. Multicharged ion-induced emission from metal- and insulator surfaces related to magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Winter, H.P. [Technische Univ., Vienna (Austria). Inst. fuer Allgemeine Physik

    1997-01-01

    The edge region of magnetically confined plasmas in thermonuclear fusion experiments couples the hot plasma core with the cold first wall. We consider the dependence of plasma-wall interaction processes on edge plasma properties, with particular emphasis on the role of slow multicharged ions (MCI). After a short survey on the physics of slow MCI-surface interaction we discuss recent extensive studies on MCI-induced electron emission from clean metal surfaces conducted at impact velocities << 1 a.u., from which generally reliable total electron yields can be obtained. We then demonstrate the essentially different role of the MCI charge for electron emission from metallic and insulator surfaces, respectively. Furthermore, we present recent results on slow MCI-induced `potential sputtering` of insulators which, in contrast to the well established kinetic sputtering, already occurs at very low ion impact energy and strongly increases with the MCI charge state. (J.P.N.). 55 refs.

  4. Nanomechanical investigation of ion implanted single crystals - Challenges, possibilities and pitfall traps related to nanoindentation

    Science.gov (United States)

    Kurpaska, Lukasz

    2017-10-01

    Nanoindentation technique have developed considerably over last thirty years. Nowadays, commercially available systems offer very precise measurement in nano- and microscale, environmental noise cancelling (or at least noise suppressing), in situ high temperature indentation in controlled atmosphere and vacuum conditions and different additional options, among them dedicated indentation is one of the most popular. Due to its high precision, and ability to measure mechanical properties from very small depths (tens of nm), this technique become quite popular in the nuclear society. It is known that ion implantation (to some extent) can simulate the influence of neutron flux. However, depth of the material damage is very limited resulting in creation of thin layer of modified material over unmodified bulk. Therefore, only very precise technique, offering possibility to control depth of the measurement can be used to study functional properties of the material. For this reason, nanoindentation technique seems to be a perfect tool to investigate mechanical properties of ion implanted specimens. However, conducting correct nanomechanical experiment and extracting valuable mechanical parameters is not an easy task. In this paper a discussion about the nanoindentation tests performed on ion irradiated YSZ single crystal is presented. The goal of this paper is to discuss possible traps when studying mechanical properties of such materials and thin coatings.

  5. [Application of classical isothermal adsorption models in heavy metal ions/ diatomite system and related problems].

    Science.gov (United States)

    Zhu, Jian; Wu, Qing-Ding; Wang, Ping; Li, Ke-Lin; Lei, Ming-Jing; Zhang, Wei-Li

    2013-11-01

    In order to fully understand adsorption nature of Cu2+, Zn2+, Pb2+, Cd2+, Mn2+, Fe3+ onto natural diatomite, and to find problems of classical isothermal adsorption models' application in liquid/solid system, a series of isothermal adsorption tests were conducted. As results indicate, the most suitable isotherm models for describing adsorption of Pb2+, Cd2+, Cu2+, Zn2+, Mn2+, Fe3+ onto natural diatomite are Tenkin, Tenkin, Langmuir, Tenkin, Freundlich and Freundlich, respectively, the adsorption of each ion onto natural diatomite is mainly a physical process, and the adsorption reaction is favorable. It also can be found that, when using classical isothermal adsorption models to fit the experimental data in liquid/solid system, the equilibrium adsorption amount q(e) is not a single function of ion equilibrium concentration c(e), while is a function of two variables, namely c(e) and the adsorbent concentration W0, q(e) only depends on c(e)/W(0). Results also show that the classical isothermal adsorption models have a significant adsorbent effect, and their parameter values are unstable, the simulation values of parameter differ greatly from the measured values, which is unhelpful for practical use. The tests prove that four-adsorption-components model can be used for describing adsorption behavior of single ion in nature diatomite-liquid system, its parameters k and q(m) have constant values, which is favorable for practical quantitative calculation in a given system.

  6. NASA Aerospace Flight Battery Program: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries; Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries; Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop). Volume 1, Part 1

    Science.gov (United States)

    Manzo, Michelle A.; Brewer, Jeffrey C.; Bugga, Ratnakumar V.; Darcy, Eric C.; Jeevarajan, Judith A.; McKissock, Barbara I.; Schmitz, Paul C.

    2010-01-01

    This NASA Aerospace Flight Battery Systems Working Group was chartered within the NASA Engineering and Safety Center (NESC). The Battery Working Group was tasked to complete tasks and to propose proactive work to address battery related, agency-wide issues on an annual basis. In its first year of operation, this proactive program addressed various aspects of the validation and verification of aerospace battery systems for NASA missions. Studies were performed, issues were discussed and in many cases, test programs were executed to generate recommendations and guidelines to reduce risk associated with various aspects of implementing battery technology in the aerospace industry. This document contains Part 1 - Volume I: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries, Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries, and Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop).

  7. Energies of rare-earth ion states relative to host bands in optical materials from electron photoemission spectroscopy

    Science.gov (United States)

    Thiel, Charles Warren

    There are a vast number of applications for rare-earth-activated materials and much of today's cutting-edge optical technology and emerging innovations are enabled by their unique properties. In many of these applications, interactions between the rare-earth ion and the host material's electronic states can enhance or inhibit performance and provide mechanisms for manipulating the optical properties. Continued advances in these technologies require knowledge of the relative energies of rare-earth and crystal band states so that properties of available materials may be fully understood and new materials may be logically developed. Conventional and resonant electron photoemission techniques were used to measure 4f electron and valence band binding energies in important optical materials, including YAG, YAlO3, and LiYF4. The photoemission spectra were theoretically modeled and analyzed to accurately determine relative energies. By combining these energies with ultraviolet spectroscopy, binding energies of excited 4fN-15d and 4fN+1 states were determined. While the 4fN ground-state energies vary considerably between different trivalent ions and lie near or below the top of the valence band in optical materials, the lowest 4f N-15d states have similar energies and are near the bottom of the conduction band. As an example for YAG, the Tb3+ 4f N ground state is in the band gap at 0.7 eV above the valence band while the Lu3+ ground state is 4.7 eV below the valence band maximum; however, the lowest 4fN-15d states are 2.2 eV below the conduction band for both ions. We found that a simple model accurately describes the binding energies of the 4fN, 4fN-1 5d, and 4fN+1 states. The model's success across the entire rare-earth series indicates that measurements on two different ions in a host are sufficient to predict the energies of all rare-earth ions in that host. This information provides new insight into electron transfer transitions, luminescence quenching, and valence

  8. Oxide ion diffusion mechanism related to Co and Fe ions in (Ba0.5Sr0.5)(Co0.8Fe0.2)O3-δ using in-situ X-ray absorption spectroscopy

    Science.gov (United States)

    Itoh, Takanori; Imai, Hideto

    2018-03-01

    The time changes of the white line and pre-edge intensities of Co and Fe K-edge in (Ba0.5Sr0.5)(Co0.8Fe0.2)O3-δ (BSCF) were observed to estimate the oxide ion diffusion related to Co and Fe ions by using in - situ X-ray absorption spectroscopy (XAS) during oxidation. The 20 μm self-standing BSCF film was prepared for in - situ XAS measurements. The time changes of absorption were fitted to the exponential decay function with two terms. The longer relaxation time (τ), related to the oxide ion diffusion during the oxidation of BSCF, is dependent on temperature. The oxide ion diffusion coefficients (D) were calculated from the τ s estimated by in - situ XAS. The values of the activation energy (Ea) for D related to Co K-edge white line, Co pre-edge, and Fe pre-edge were 1.8-2.0 eV. The value of Ea for D related to Fe K-edge white line, however, was higher than other absorption values at approximately 2.3 eV. We discussed the oxide ion diffusion mechanism related to Co and Fe ions in BSCF using in - situ XAS.

  9. Magnetic field related mechanical tolerances for the proposed Chalk River superconducting heavy-ion cyclotron

    International Nuclear Information System (INIS)

    Heighway, E.A.; Chaplin, K.R.

    1977-11-01

    A four sector azimuthally varying field cyclotron with superconducting main coils has been proposed as a heavy-ion post-accelerator for the Chalk River MP Tandem van de Graaff. The radial profile of the average axial field will be variable using movable steel trim rods. The field errors due to coil, trim rod and flutter pole imperfections are calculated. Those considered are errors in the axial field, first and second azimuthal harmonic axial fields, transverse field and first azimuthal harmonic transverse field. Such fields induce phase slip, axial or radial coherent oscillations and can result in axial or radial beam instability. The allowed imperfections (tolerances) required to retain stability and maintain acceptably small coherent oscillation amplitudes are calculated. (author)

  10. Material-related issues at high-power and high-energy ion beam facilities

    CERN Document Server

    Bender, M.; Tomut, M.; Trautmann, C.

    2015-01-01

    When solids are exposed to energetic ions (MeV-GeV), their physical and chemical structure can be severely modified. The change is governed by ultrafast dynamical processes starting from the deposition of large energy densities, electronic excitation and ionization processes, and finally damage creation in the atomic lattice system. In many materials, each projectile creates a cylindrical track with a few nanometers in diameter and up to many μm in length. To study and monitor the creation of damage, the GSI irradiation facility dedicated to materials science provides different in-situ and on-line techniques such as high resolution microscopy, X-ray diffraction, optical absorption spectroscopy, thermal imaging and residual gas analysis. The irradiation experiments can be performed under various gas atmospheres and under cryogenic or elevated temperature.

  11. WE-H-BRA-09: Application of a Modified Microdosimetric-Kinetic Model to Analyze Relative Biological Effectiveness of Ions Relevant to Light Ion Therapy Using the Particle Heavy Ion Transport System

    Energy Technology Data Exchange (ETDEWEB)

    Butkus, M [Yale-New Haven Hospital, New Haven, CT (United States); Palmer, T [Oregon State University, Corvallis, OR (United States)

    2016-06-15

    Purpose: To evaluate the dose and biological effectiveness of various ions that could potentially be used for actively scanned particle therapy. Methods: The PHITS Monte Carlo code paired with a microscopic analytical function was used to determine probability distribution functions of the lineal energy in 0.3µm diameter spheres throughout a water phantom. Twenty million primary particles for 1H beams and ten million particles for 4He, 7Li, 10B, 12C, 14N, 16O, and 20Ne were simulated for 0.6cm diameter pencil beams. Beam energies corresponding to Bragg peak depths of 50, 100, 150, 200, 250, and 300mm were used and evaluated transversely every millimeter and radially in annuli with outer radius of 1.0, 2.0, 3.0, 3.2, 3.4, 3.6, 4.0, 5.0, 10.0, 15.0, 20.0 and 25.0mm. The acquired probability distributions were reduced to dose-mean lineal energies and applied to the modified microdosimetric kinetic model for five different cell types to calculate relative biological effectiveness (RBE) compared to 60Co beams at the 10% survival threshold. The product of the calculated RBEs and the simulated physical dose was taken to create biological dose and comparisons were then made between the various ions. Results: Transversely, the 10B beam was seen to minimize relative biological dose in both the constant and accelerated dose change regions, proximal to the Bragg Peak, for all beams traveling greater than 50mm. For the 50mm beam, 7Li was seen to provide the most optimal biological dose profile. Radially small fluctuations (<4.2%) were seen in RBE while physical dose was greater than 1% for all beams. Conclusion: Even with the growing usage of 12C, it may not be the most optimal ion in all clinical situations. Boron was calculated to have slightly enhanced RBE characteristics, leading to lower relative biological doses.

  12. Linear rate-equilibrium relations arising from ion channel-bilayer energetic coupling

    DEFF Research Database (Denmark)

    Greisen, Per Junior; Lum, Kevin; Ashrafuzzaman, Md

    2011-01-01

    Linear rate-equilibrium (RE) relations, also known as linear free energy relations, are widely observed in chemical reactions, including protein folding, enzymatic catalysis, and channel gating. Despite the widespread occurrence of linear RE relations, the principles underlying the linear relatio...

  13. Salts and nutrients present in regenerated waters induce changes in water relations, antioxidative metabolism, ion accumulation and restricted ion uptake in Myrtus communis L. plants.

    Science.gov (United States)

    Acosta-Motos, José R; Alvarez, Sara; Barba-Espín, Gregorio; Hernández, José A; Sánchez-Blanco, María J

    2014-12-01

    The use of reclaimed water (RW) constitutes a valuable strategy for the efficient management of water and nutrients in landscaping. However, RW may contain levels of toxic ions, affecting plant production or quality, a very important aspect for ornamental plants. The present paper evaluates the effect of different quality RWs on physiological and biochemical parameters and the recovery capacity in Myrtus communis L. plants. M. communis plants were submitted to 3 irrigation treatments with RW from different sources (22 weeks): RW1 (1.7 dS m(-1)), RW2 (4.0 dS m(-1)) and RW3 (8.0 dS m(-1)) and one control (C, 0.8 dS m(-1)). During a recovery period of 11 weeks, all plants were irrigated with the control water. The RW treatments did not negatively affect plant growth, while RW2 even led to an increase in biomass. After recovery,only plants irrigated with RW3 showed some negative effects on growth, which was related to a decrease in the net photosynthesis rate, higher Na accumulation and a reduction in K levels. An increase in salinity was accompanied by decreases in leaf water potential, relative water content and gas exchange parameters, and increases in Na and Cl uptake. Plants accumulated Na in roots and restricted its translocation to the aerial part. The highest salinity levels produced oxidative stress, as seen from the rise in electrolyte leakage and lipid peroxidation. The use of regenerated water together with carefully managed drainage practices, which avoid the accumulation of salt by the substrate, will provide economic and environmental benefits.

  14. Alkali Metal Ion Complexes with Phosphates, Nucleotides, Amino Acids, and Related Ligands of Biological Relevance. Their Properties in Solution.

    Science.gov (United States)

    Crea, Francesco; De Stefano, Concetta; Foti, Claudia; Lando, Gabriele; Milea, Demetrio; Sammartano, Silvio

    2016-01-01

    Alkali metal ions play very important roles in all biological systems, some of them are essential for life. Their concentration depends on several physiological factors and is very variable. For example, sodium concentrations in human fluids vary from quite low (e.g., 8.2 mmol dm(-3) in mature maternal milk) to high values (0.14 mol dm(-3) in blood plasma). While many data on the concentration of Na(+) and K(+) in various fluids are available, the information on other alkali metal cations is scarce. Since many vital functions depend on the network of interactions occurring in various biofluids, this chapter reviews their complex formation with phosphates, nucleotides, amino acids, and related ligands of biological relevance. Literature data on this topic are quite rare if compared to other cations. Generally, the stability of alkali metal ion complexes of organic and inorganic ligands is rather low (usually log K  Na(+) > K(+) > Rb(+) > Cs(+). For example, for citrate it is: log K ML = 0.88, 0.80, 0.48, 0.38, and 0.13 at 25 °C and infinite dilution. Some considerations are made on the main aspects related to the difficulties in the determination of weak complexes. The importance of the alkali metal ion complexes was also studied in the light of modelling natural fluids and in the use of these cations as probes for different processes. Some empirical relationships are proposed for the dependence of the stability constants of Na(+) complexes on the ligand charge, as well as for correlations among log K values of NaL, KL or LiL species (L = generic ligand).

  15. Variations in Calcium and Alginate Ions Concentration in Relation to the Properties of Calcium Alginate Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hamed Daemi

    2013-05-01

    Full Text Available Alginate belongs to a group of natural polymers called polysaccharides. They have carboxylic functional groups beside hydroxyls which are common in all polysaccharides. These materials show interesting properties due to theirfunctional groups. One of these properties is the ability of this polymer as a suitable carrier of protecting and transferring drugs and biomolecules. The particle sizes of these polymers are very important for their applications, so different techniques were used for preparation of these materials. In this way polymeric nanoparticles of calcium alginate which are excellent carriers in drug delivery systems were prepared by addition of calcium chloride solution to dilute solution of sodium alginate. Investigation of the size and distribution of nanoparticles were analyzed by SEM method. The concentration effects of both alginate and calcium ions on the size and distribution of  nanoparticles were studied in this research. Results showed that the size of nanoparticles obviously decreased with decreasing polymeric alginate concentration because of lower active sites in polymer chain. On the other hand, thesize and distribution of nanoparticles are significantly improved with increase of calcium cation concentrations. The mean particle size 40-70 nm and spherical shape are the main characteristics of the prepared nanoparticles.

  16. A study of process-related electrical defects in SOI lateral bipolar transistors fabricated by ion implantation

    Science.gov (United States)

    Yau, J.-B.; Cai, J.; Hashemi, P.; Balakrishnan, K.; D'Emic, C.; Ning, T. H.

    2018-04-01

    We report a systematic study of process-related electrical defects in symmetric lateral NPN transistors on silicon-on-insulator (SOI) fabricated using ion implantation for all the doped regions. A primary objective of this study is to see if pipe defects (emitter-collector shorts caused by locally enhanced dopant diffusion) are a show stopper for such bipolar technology. Measurements of IC-VCE and Gummel currents in parallel-connected transistor chains as a function of post-fabrication rapid thermal anneal cycles allow several process-related electrical defects to be identified. They include defective emitter-base and collector-base diodes, pipe defects, and defects associated with a dopant-deficient region in an extrinsic base adjacent its intrinsic base. There is no evidence of pipe defects being a major concern in SOI lateral bipolar transistors.

  17. 2-(trimethylammonium)ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate promotes megakaryocytic differentiation of myeloid leukaemia cells and primary human CD34⁺ haematopoietic stem cells.

    Science.gov (United States)

    Limb, Jin-Kyung; Song, Doona; Jeon, Mijeong; Han, So-Yeop; Han, Gyoonhee; Jhon, Gil-Ja; Bae, Yun Soo; Kim, Jaesang

    2015-04-01

    In this study we showed that 2-(trimethylammonium)ethyl (R)-3-methoxy-3-oxo-2-stearamidopropyl phosphate [(R)-TEMOSPho], a derivative of an organic chemical identified from a natural product library, promotes highly efficient differentiation of megakaryocytes. Specifically, (R)-TEMOSPho induces cell cycle arrest, cell size increase and polyploidization from K562 and HEL cells, which are used extensively to model megakaryocytic differentiation. In addition, megakaryocyte-specific cell surface markers showed a dramatic increase in expression in response to (R)-TEMOSPho treatment. Importantly, we demonstrated that such megakaryocytic differentiation can also be induced from primary human CD34(+) haematopoietic stem cells. Activation of the PI3K-AKT pathway and, to a lesser extent, the MEK-ERK pathway appears to be required for this process, as blocking with specific inhibitors interferes with the differentiation of K562 cells. A subset of (R)-TEMOSPho-treated K562 cells undergoes spontaneous apoptosis and produces platelets that are apparently functional, as they bind to fibrinogen, express P-selectin and aggregate in response to SFLLRN and AYPGFK, the activating peptides for the PAR1 and PAR4 receptors, respectively. Taken together, these results indicate that (R)-TEMOSPho will be useful for dissecting the molecular mechanisms of megakaryocytic differentiation, and that this class of compounds represents potential therapeutic reagents for thrombocytopenia. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Optical effects of ion implantation

    International Nuclear Information System (INIS)

    Townsend, P.D.

    1987-01-01

    The review concerns the effects of ion implantation that specifically relate to the optical properties of insulators. Topics which are reviewed include: ion implantation, ion range and damage distributions, colour centre production by ion implantation, high dose ion implantation, and applications for integrated optics. Numerous examples are presented of both diagnostic and industrial examples of ion implantation effects in insulators. (U.K.)

  19. Method of assessing a lipid-related health risk based on ion mobility analysis of lipoproteins

    Science.gov (United States)

    Benner, W. Henry; Krauss, Ronald M.; Blanche, Patricia J.

    2010-12-14

    A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

  20. Acid-sensing ion channel (ASIC) 4 predominantly localizes to an early endosome-related organelle upon heterologous expression.

    Science.gov (United States)

    Schwartz, Verena; Friedrich, Katharina; Polleichtner, Georg; Gründer, Stefan

    2015-12-15

    Acid-sensing ion channels (ASICs) are voltage-independent proton-gated amiloride sensitive sodium channels, belonging to the DEG/ENaC gene family. Six different ASICs have been identified (ASIC1a, ASIC1b, ASIC2a, ASIC2b, ASIC3, ASIC4) that are activated by a drop in extracellular pH, either as homo- or heteromers. An exception is ASIC4, which is not activated by protons as a homomer and which does not contribute to functional heteromeric ASICs. Insensitivity of ASIC4 to protons and its comparatively low sequence identity to other ASICs (45%) raises the question whether ASIC4 may have different functions than other ASICs. In this study, we therefore investigated the subcellular localization of ASIC4 in heterologous cell lines, which revealed a surprising accumulation of the channel in early endosome-related vacuoles. Moreover, we identified an unique amino-terminal motif as important for forward-trafficking from the ER/Golgi to the early endosome-related compartment. Collectively, our results show that heterologously expressed ASIC4 predominantly resides in an intracellular endosomal compartment.

  1. Impact of He and H relative depth distributions on the result of sequential He+ and H+ ion implantation and annealing in silicon

    Science.gov (United States)

    Cherkashin, N.; Daghbouj, N.; Seine, G.; Claverie, A.

    2018-04-01

    Sequential He++H+ ion implantation, being more effective than the sole implantation of H+ or He+, is used by many to transfer thin layers of silicon onto different substrates. However, due to the poor understanding of the basic mechanisms involved in such a process, the implantation parameters to be used for the efficient delamination of a superficial layer are still subject to debate. In this work, by using various experimental techniques, we have studied the influence of the He and H relative depth-distributions imposed by the ion energies onto the result of the sequential implantation and annealing of the same fluence of He and H ions. Analyzing the characteristics of the blister populations observed after annealing and deducing the composition of the gas they contain from FEM simulations, we show that the trapping efficiency of He atoms in platelets and blisters during annealing depends on the behavior of the vacancies generated by the two implants within the H-rich region before and after annealing. Maximum efficiency of the sequential ion implantation is obtained when the H-rich region is able to trap all implanted He ions, while the vacancies it generated are not available to favor the formation of V-rich complexes after implantation then He-filled nano-bubbles after annealing. A technological option is to implant He+ ions first at such an energy that the damage it generates is located on the deeper side of the H profile.

  2. Evaluation of the relative biological effectiveness of carbon ion beams in the cerebellum using the rat organotypic slice culture system

    International Nuclear Information System (INIS)

    Yoshida, Yukari; Katoh, Hiroyuki; Nakano, Takashi; Suzuki, Yoshiyuki; Al-Jahdari, Wael S.; Shirai, Katsuyuki; Hamada, Nobuyuki; Funayama, Tomoo; Sakashita, Tetsuya; Kobayashi, Yasuhiko

    2012-01-01

    The purpose of this study was to clarify the relative biological effectiveness (RBE) values of carbon ion (C) beams in normal brain tissues, a rat organotypic slice culture system was used. The cerebellum was dissected from 10-day-old Wistar rats, cut parasagittally into approximately 600-μm-thick slices and cultivated using a membrane-based culture system with a liquid-air interface. Slices were irradiated with 140 kV X-rays and 18.3 MeV/amu C-beams (linear energy transfer=108 keV/μm). After irradiation, the slices were evaluated histopathologically using hematoxylin and eosin staining, and apoptosis was quantified using the TdT-mediated dUTP-biotin nick-end labeling (TUNEL) assay. Disorganization of the external granule cell layer (EGL) and apoptosis of the external granule cells (EGCs) were induced within 24 h after exposure to doses of more than 5 Gy from C-beams and X-rays. In the early postnatal cerebellum, morphological changes following exposure to C-beams were similar to those following exposure to X-rays. The RBEs values of C-beams using the EGL disorganization and the EGC TUNEL index endpoints ranged from 1.4 to 1.5. This system represents a useful model for assaying the biological effects of radiation on the brain, especially physiological and time-dependent phenomena. (author)

  3. Relation between track structure and LET effect on free radical formation for ion beam-irradiated alanine dosimeter

    International Nuclear Information System (INIS)

    Krushev, V.V.; Koizumi, Hitoshi; Ichikawa, Tsuneki; Yoshida, Hiroshi; Shibata, Hiromi; Tagawa, Seiichi; Yoshida, Yoichi

    1994-01-01

    The yield and local concentration of free radicals generated from alanine (α-aminopropionic acid) by irradiation with 3 MeV H + and He + ions were examined by means of electron spin resonance (ESR) and ESR power saturation methods at room temperature. The G-value of the radical formation showed a marked dependence on linear energy transfer (LET) of the ions. The G-value for the H + ion (average LET: 28 eV/nm) was almost the same as that for γ-irradiation and it was smaller by a factor of 1/4.7 for the He + ion (average LET: 225eV/nm). Combining the local concentration of the free radicals along the ion tracks with the G-values and the reported ion range, the radius of a track filled with free radicals was estimated to be 4 ∼ 5 nm by assuming a simple rod-shaped track with a constant radius and homogeneous distribution of the free radicals in it. The track radius scarcely depends on the LET within the range examined. The radiation energy deposited in the core region of the ion track was concluded to spread over the rod to generate free radicals. (author)

  4. Ion mobilities and ion-atom interaction potentials

    International Nuclear Information System (INIS)

    Gatland, I.R.

    1982-01-01

    The techniques for measuring the mobilities of ions in gases, relating interaction potentials to mobilities, and determining potentials from experimental mobilities are reviewed. Applications are presented for positive alkali ions and negative halogen ions in inert gases. (Auth.)

  5. Study in the plasma with non-equilibrium ionization state by relative intensities in K-spectra of multicharged ions

    International Nuclear Information System (INIS)

    Bojko, V.A.; Skobelev, I.Yu.; Faenov, A.Ya.

    1984-01-01

    The pressure of the K-spectra formation of multicharge h-, He-, Li-like ions in a plasma with an arbitrary ionization state are considered. It is shown that comparison of experimental and theoretical data on the intensities of f a number of spectral lines belonging to such ions allows one to determine both the plasma electron temperature and ion distribution versus the ionization degre ees. The proposed method of plasma diagnostics is used for measuring parameters of the expanding laser-produced magnesium plasme

  6. The induction of genomic instability in related human lymphoblasts following exposure to Cs gamma radiation vs accelerated 56Fe Ions

    International Nuclear Information System (INIS)

    Evans, H.H.; Horng, M.-F.; Ricanati, M.; Diaz-Insua, M.

    2003-01-01

    Full text: The induction of genomic instability by exposure to Cs-137 gamma radiation and Fe-56 accelerated ions was investigated by measuring the frequency and characteristics of TK6 and WTK1 unstable clones isolated 36 generations after exposure. While the two cell lines are related, TK6 is more sensitive to radiation, has normal p53 expression, and is repair deficient. Clones surviving the radiation and respective controls were analyzed for 17 characteristics including chromosomal aberrations, growth defects, alterations in response to a second radiation and mutant frequencies at two different loci. Putative unstable clones were defined as those exhibiting a significant alteration in one or more characteristics as compared to the respective control medians. Over half of the unstable WTK1 clones and over 90% of the TK6 unstable clones surviving exposure to either radiation exhibited chromosomal instability, the major aberrations consisting of chromatid breaks and dicentric chromosomes formed by end-to-end fusions. Alterations in the other measured characteristics occurred much less often than cytogenetic alterations in the TK6 unstable clones. The phenotype of the WTK1 unstable clones was more diverse and complex than in the case of TK6 unstable clones. The phenotype of the TK6 unstable clones differed in the survivors of Cs-137 vs. Fe-56. In the clones surviving Cs-137, the aberrations consisted mainly of dicentric chromosomes, while clones surviving exposure to Fe-56 exhibited both breaks and dicentrics. The uniform prevalence of chromosomal aberrations in the unstable TK6 clones vs. the relatively diverse phenotype of the unstable WTK1 clones suggests that the deficiency in DNA double-strand break repair in TK6 cells may be accompanied by a deficiency in telomere maintenance that leads to telomere fusion, dicentric chromosomes, anaphase bridges, breakage and the occurrence of chromosomal instability in the majority of clones isolated following exposure

  7. Production of amorphous metal layers using ion implantation and investigation of the related modification of some surface properties

    International Nuclear Information System (INIS)

    Hoang Dac Luc; Vu Hoang Lam.

    1993-01-01

    Amorphous layers were produced by implanting B + ions into Al at 50 keV. The modification of the electrochemical corrosion resistance and the mechanical strength of implanted specimen was investigated. (author). 2 refs, 1 tab, 2 figs

  8. Inhibition of potential lethal damage repair and related gene expression after carbon-ion beam irradiation to human lung cancer grown in nude mice

    International Nuclear Information System (INIS)

    Yashiro, Tomoyasu; Fujisawa, Takehiko; Koyama-Saegusa, Kumiko; Imai, Takashi; Miyamoto, Tadaaki

    2007-01-01

    Using cultured and nude mouse tumor cells (IA) derived from a human lung cancer, we previously demonstrated their radiosensitivity by focusing attention on the dynamics of tumor clonogens and the early and rapid survival recovery (potential lethal damage repair: PLD repair) occurring after X-ray irradiation. To the authors' knowledge, this is the first study demonstrating gene expression in association with PLD repair after carbon-ion beam or X-ray irradiation to cancer cells. In this study we tried to detect the mechanism of DNA damage and repair of the clonogens after X-ray or carbon-ion beam irradiation. At first, colony assay method was performed after irradiation of 12 Gy of X-ray or 5 Gy of carbon-ion beam to compare the time dependent cell survival of the IA cells after each irradiation pass. Second, to search the genes causing PLD repair after irradiation of X-ray or carbon-ion beam, we evaluated gene expressions by using semi-quantitative RT-PCR with the selected 34 genes reportedly related to DNA repair. The intervals from the irradiation were 0, 6, 12 and 24 hr for colony assay method, and 0, 3, 18 hr for RT-PCR method. From the result of survival assays, significant PLD repair was not observed in carbon-ion beam as compared to X-ray irradiation. The results of RT-PCR were as follows. The gene showing significantly higher expressions after X-ray irradiation than after carbon-ion beam irradiation was PCNA. The genes showing significantly lower expressions after X-ray irradiation rather than after carbon-ion beam irradiation were RAD50, BRCA1, MRE11A, XRCC3, CHEK1, MLH1, CCNB1, CCNB2 and LIG4. We conclude that PCNA could be a likely candidate gene for PLD repair. (author)

  9. Release of titanium ions from an implant surface and their effect on cytokine production related to alveolar bone resorption

    International Nuclear Information System (INIS)

    Wachi, Takanori; Shuto, Takahiro; Shinohara, Yoshinori; Matono, Yoshinari; Makihira, Seicho

    2015-01-01

    Although interest in peri-implant mucositis and peri-implantitis has recently been increasing, the mechanisms driving these diseases remain unknown. Here, the effects of titanium ions on the inflammation and bone resorption around an implant were investigated. First, the accumulated amount of Ti ions released into gingival and bone tissues from an implant exposed to sodium fluoride solution was measured using inductively coupled plasma mass spectrometry. Next, the cellular responses in gingival and bone tissues to Ti ions and/or Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS) were assessed using a rat model. More Ti ions were detected in the gingival tissues around an implant after treatment with sodium fluoride (pH 4.2) than in its absence, which suggests that the fluoride corroded the implant surface under salivary buffering capacity. The injection of Ti ions (9 ppm) significantly increased the mRNA expression and protein accumulation of chemokine (C–C motif) ligand 2, as well as the ratio of receptor activator of nuclear factor-κB ligand to osteoprotegerin, in rat gingival tissues exposed to P. gingivalis-LPS in a synergistic manner. In addition, the enhanced localization of toll-like receptor 4, which is an LPS receptor, was observed in gingival epithelium loaded with Ti ions (9 ppm). These data suggest that Ti ions may be partly responsible for the infiltration of monocytes and osteoclast differentiation by increasing the sensitivity of gingival epithelial cells to microorganisms in the oral cavity. Therefore, Ti ions may be involved in the deteriorating effects of peri-implant mucositis, which can develop into peri-implantitis accompanied by alveolar bone resorption

  10. Generation of zonal flows by ion-temperature-gradient and related modes in the presence of neoclassical viscosity

    International Nuclear Information System (INIS)

    Mikhailovskii, A.B.; Smolyakov, A.I.; Kovalishen, E.A.; Shirokov, M.S.; Tsypin, V.S.; Galvao, R.M.O.

    2006-01-01

    Generation of zonal flows by primary waves that are more complex than those considered in the standard drift-wave model is studied. The effects of parallel ion velocity and ion perturbed temperature and the part of the nonlinear mode interaction proportional to the ion pressure are taken into account. This generalization of the standard model allows the analysis of generation of zonal flows by a rather wide variety of primary modes, including ion temperature gradients, ion sound, electron drift, and drift-sound modes. All the listed effects, which are present in the slab geometry model, are complemented by effects of neoclassical viscosity inherent to toroidal geometry. We show that the electrostatic potential of secondary small-scale modes is expressed in terms of a nonlinear shift of the mode frequency and interpret this shift in terms of the perpendicular and parallel Doppler, nonlinear Kelvin-Helmholtz (KH), and nonlinear ion-pressure-gradient effects. A basic assumption of our model is that the primary modes form a nondispersive monochromatic wave packet. The analysis of zonal-flow generation is performed following an approach similar to that of convective-cell theory. Neoclassical zonal-flow instabilities are separated into fast and slow ones, and these are divided into two varieties. The first of them is independent of the nonlinear KH effect, while the second one is sensitive to it

  11. Detector Characterization Report, Response Related to Linear Movement and Radiation Levels for an Oak Ridge National Laboratory (ORNL)-Developed Ion Chamber and a Commercial Ion Chamber

    International Nuclear Information System (INIS)

    Chiaro, P.J.

    2001-01-01

    Recent activities regarding the safeguarding of radioactive material have indicated there is a need to use radiation sensors to monitor intentional or unintentional material movement. Existing radiation detection systems were not typically designed for this type of operation since most of their use accounted for monitoring material while the material is stationary. To ensure that a radiation monitoring system is capable of detecting the movement of radioactive material, a series of tests were needed. These tests would need to be performed in known radiological conditions, under controlled environmental conditions, and at known movement speeds. The Radiation Effects Facility (REF), located at the Radiation Calibration Laboratory, provided the necessary capabilities to perform these tests. This report provides a compilation of the results from a characterization of two different sensors--a simple, air ionization chamber-based sensor developed at ORNL that consists of an ion chamber connected to a separate amplifier, and an Eberline model RO-7-LD. The RO-7-LD is also an air ionization chamber-based sensor, but the electronics are in the same physical package

  12. Dose-volume histogram analysis of hepatic toxicity related to carbon ion radiation therapy of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Yasuda, Shigeo; Kato, Hirotoshi; Tsujii, Hitohiko; Mizoe, Junetsu

    2005-01-01

    The purpose of this study is to analyze the correlation of hepatic toxicity with dose-volume factors of carbon ion radiotherapy in the liver. Forty-nine patients with hepatocellular carcinoma were treated with carbon ion radiotherapy delivered in 4 fractions over 4 to 7 days. Six patients received a total dose of 48 GyE and 43 received 52.8 GyE. The correlation of various blood biochemistry data with dose-volume histogram (DVH) data in non-cancerous liver were evaluated. The strongest significant correlation was seen between percent volume of non-cancerous liver with radiation dose more than 11 GyE (V 11 GyE ) and elevation of serum glutamic oxaloacetic transaminase (GOT) level as early adverse response after carbon ion beam radiation therapy (p=0.0003). In addition, significant correlation between DVH data and change of several other blood biochemistry data were also revealed in early phase. In late phase after carbon ion radiotherapy, the strongest significant correlation was seen between decrease of platelet count and V 26GyE (p=0.015). There was no significant correlation between other blood biochemistry data and DVH data in the late phase. It was suggested that dose-volume factors of carbon ion radiotherapy influenced only transient aggravation of liver function, which improved in the long term after irradiation. (author)

  13. Rapid MCNP simulation of DNA double strand break (DSB) relative biological effectiveness (RBE) for photons, neutrons, and light ions.

    Science.gov (United States)

    Stewart, Robert D; Streitmatter, Seth W; Argento, David C; Kirkby, Charles; Goorley, John T; Moffitt, Greg; Jevremovic, Tatjana; Sandison, George A

    2015-11-07

    To account for particle interactions in the extracellular (physical) environment, information from the cell-level Monte Carlo damage simulation (MCDS) for DNA double strand break (DSB) induction has been integrated into the general purpose Monte Carlo N-particle (MCNP) radiation transport code system. The effort to integrate these models is motivated by the need for a computationally efficient model to accurately predict particle relative biological effectiveness (RBE) in cell cultures and in vivo. To illustrate the approach and highlight the impact of the larger scale physical environment (e.g. establishing charged particle equilibrium), we examined the RBE for DSB induction (RBEDSB) of x-rays, (137)Cs γ-rays, neutrons and light ions relative to γ-rays from (60)Co in monolayer cell cultures at various depths in water. Under normoxic conditions, we found that (137)Cs γ-rays are about 1.7% more effective at creating DSB than γ-rays from (60)Co (RBEDSB  =  1.017) whereas 60-250 kV x-rays are 1.1 to 1.25 times more efficient at creating DSB than (60)Co. Under anoxic conditions, kV x-rays may have an RBEDSB up to 1.51 times as large as (60)Co γ-rays. Fission neutrons passing through monolayer cell cultures have an RBEDSB that ranges from 2.6 to 3.0 in normoxic cells, but may be as large as 9.93 for anoxic cells. For proton pencil beams, Monte Carlo simulations suggest an RBEDSB of about 1.2 at the tip of the Bragg peak and up to 1.6 a few mm beyond the Bragg peak. Bragg peak RBEDSB increases with decreasing oxygen concentration, which may create opportunities to apply proton dose painting to help address tumor hypoxia. Modeling of the particle RBE for DSB induction across multiple physical and biological scales has the potential to aid in the interpretation of laboratory experiments and provide useful information to advance the safety and effectiveness of hadron therapy in the treatment of cancer.

  14. Hydrogen ion species analysis and related neutral beam injection power assessment in the Heliotron E neutral beam injection system

    International Nuclear Information System (INIS)

    Sano, Fumimichi; Obiki, Tokuhiro; Sasaki, Akihiko; Iiyoshi, Atsuo; Uo, Koji

    1982-01-01

    The hydrogen ion species in a Heliotron E neutral beam injection system of maximum electric power 6.3 MW were analyzed in order to assess the neutral beam power injected into the torus. The masimum p roton ratio of the cylindrical bucket type ion source used was observed to be more than 90 percent assuming that the angular divergences for the respective species in the beam are the same. The experimental data are compared with calculations using a particle balance model. The analysis indicates that the net injection power reaches nearly 2.7 MW at the optimal conditions of the system considering the geometrical limitation of the neutral beam path. (author)

  15. Ab initio/GIAO-CCSD(T) study of structures, energies, and 13C NMR chemical shifts of C4H7(+) and C5H9(+) ions: relative stability and dynamic aspects of the cyclopropylcarbinyl vs bicyclobutonium ions.

    Science.gov (United States)

    Olah, George A; Surya Prakash, G K; Rasul, Golam

    2008-07-16

    The structures and energies of the carbocations C 4H 7 (+) and C 5H 9 (+) were calculated using the ab initio method. The (13)C NMR chemical shifts of the carbocations were calculated using the GIAO-CCSD(T) method. The pisigma-delocalized bisected cyclopropylcarbinyl cation, 1 and nonclassical bicyclobutonium ion, 2 were found to be the minima for C 4H 7 (+) at the MP2/cc-pVTZ level. At the MP4(SDTQ)/cc-pVTZ//MP2/cc-pVTZ + ZPE level the structure 2 is 0.4 kcal/mol more stable than the structure 1. The (13)C NMR chemical shifts of 1 and 2 were calculated by the GIAO-CCSD(T) method. Based on relative energies and (13)C NMR chemical shift calculations, an equilibrium involving the 1 and 2 in superacid solutions is most likely responsible for the experimentally observed (13)C NMR chemical shifts, with the latter as the predominant equilibrating species. The alpha-methylcyclopropylcarbinyl cation, 4, and nonclassical bicyclobutonium ion, 5, were found to be the minima for C 5H 9 (+) at the MP2/cc-pVTZ level. At the MP4(SDTQ)/cc-pVTZ//MP2/cc-pVTZ + ZPE level ion 5 is 5.9 kcal/mol more stable than the structure 4. The calculated (13)C NMR chemical shifts of 5 agree rather well with the experimental values of C 5H 9 (+).

  16. Physics and radiobiology of heavy charged particles in relation to the use of ion beams for therapy

    International Nuclear Information System (INIS)

    Kraft, G.; Haberer, T.; Schardt, D.; Scholz, M.

    1993-07-01

    Heavy charged particles are the most advanced tool of an external subcutane radiotherapy of deep seated tumors. Small angular- and lateral-scattering and the increase of the energy deposition with penetration depth are the physical basis for a more efficient tumor targeting. High biological efficiency in the tumor is the prerequisite for a successful treatment of tumors radioresistant against sparsely ionizing radiation. The possibility to perform target conform irradiation and to control the achieved/actual distribution using PET techniques guarantees that biological highly efficient stepping particles can be restricted to the tumor volume only. Although the physical and radiobiological properties of ion beams are very favourable for therapy, the necessity to produce these particles in an accelerator restricts a general application of heavy ions up to now. Presently the heavy ion accelerator SIS at GSI is the only source of heavy ion beams, sufficient in energy and intensity for therapy. A therapy unit is in preparation at GSI, the status of this project is given at the end of the paper. (orig.)

  17. Detection of DNA lesion induced by heavy ion irradiation using DNA repair related proteins in cultured cells

    International Nuclear Information System (INIS)

    Eguchi-Kasai, Kiyomi; Tsujita, Sena

    2006-01-01

    We studied the localization of phosphorylated H2AX (γ-H2AX) in cultured human fibroblasts after irradiation with heavy ion beams. Asynchronous human normal fibroblasts (NB1RGB) were irradiated with X-rays, C (LET≅85 keV/μm), Si (240 keV/μm), Ar (85 keV/μm), and Fe (440 keV/μm) ion beams. Gamma-H2AX was measured in irradiated cells from 0 to 24 h after irradiation using flow cytometry. The fluorescent signal of γ-H2AX increased just after irradiation of each radiation and reached maximum around 30 nun and then, decreased. At 30 min after irradiation, γ-H2AX signal increased with increasing the radiation dose for both X-rays and Fe ion. The slope of fitting line for the Fe ion was bigger than that of X-rays. Foci of γ-H2AX on cell nuclei were counted under the laser scanning confocal microscopy at 30 min after. Number of foci per nucleus was increased with increasing dose of each radiation. (author)

  18. Associative Ionization of Excited Sodium Species with Various Ligands: Assessing Relative Bonding Strengths of Ion-ligand Interactions

    Czech Academy of Sciences Publication Activity Database

    Gilligan, J. J.; McCunn, L. R.; Leskiw, B. D.; Herman, Zdeněk; Castleman Jr., A. W.

    2001-01-01

    Roč. 204, 1/3 (2001), s. 247-253 ISSN 1387-3806 Institutional research plan: CEZ:AV0Z4040901 Keywords : associative ionization * cluster ions * sodium bonding energies Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.176, year: 2001

  19. Test of special relativity theory by means of laser spectroscopy on relativistic 7Li+ ions in the ESR

    International Nuclear Information System (INIS)

    Botermann, Benjamin

    2012-01-01

    The invariance under Lorentz transformation of the laws of physics is a fundamental postulate of modern physics and all theories of the fundamental interactions have been stated in a covariant form. Although the theory of Special Relativity (SR) has been tested and confirmed with high accuracy in a large number of experiments, improved tests are of fundamental interest due to the far-reaching relevance of this postulate. Additionally modern attempts of a unified description of the four fundamental interactions point to possible violations of Lorentz invariance. In this context experiments of the Ives-Stilwell type for a test of time dilation play an important role. High resolution laser spectroscopy is applied on relativistic particle beams to investigate the validity of the relativistic Doppler formula - and therefore of the time dilation factor γ. In the course of this thesis an Ives-Stilwell experiment was performed with 7 Li + ions at a velocity of 34 % of the speed of light, which were stored at the experimental storage ring (ESR) of the GSI Helmholtzzentrum fuer Schwerionenforschung. The techniques of Λ- as well as saturation spectroscopy were employed on the 1s2s 3 S 1 →1s2p 3 P 2 transition. By a computer based analysis of the fluorescence detection system and utilization of appropriate edge filters the signal to noise ratio was decisively improved and the application of an additional pump laser allowed for the observation of a saturation signal for the first time. The frequency stability of both laser systems was specified by means of a frequency comb to obtain the highest possible accuracy. The data from the beam times were analyzed in the frameworks of the Robertson-Mansouri-Sexl test theory (RMS) and the Standard Model Extension (SME) and the corresponding upper limits of the relevant test parameters of the assigned theories were calculated. The upper limit of the parameter α was improved by a factor of 4 compared to earlier measurements performed

  20. Ion-ion collisions

    International Nuclear Information System (INIS)

    Salzborn, Erhard; Melchert, Frank

    2000-01-01

    Collisions between ions belong to the elementary processes occurring in all types of plasmas. In this article we give a short overview about collisions involving one-electron systems. For collisions involving multiply-charged ions we limit the discussion to one specific quasi-one-electron system. (author)

  1. Optimization of a Differential Ion Mobility Spectrometry-Tandem Mass Spectrometry Method for High-Throughput Analysis of Nicotine and Related Compounds: Application to Electronic Cigarette Refill Liquids.

    Science.gov (United States)

    Regueiro, Jorge; Giri, Anupam; Wenzl, Thomas

    2016-06-21

    Fast market penetration of electronic cigarettes is leading to an exponentially growing number of electronic refill liquids with different nicotine contents and an endless list of flavors. Therefore, rapid and simple methods allowing a fast screening of these products are necessary to detect harmful substances which can negatively impact the health of consumers. In this regard, the present work explores the capabilities of differential ion mobility spectrometry coupled to tandem mass spectrometry for high-throughput analysis of nicotine and 11 related compounds in commercial refill liquids for electronic cigarettes. The influence of main factors affecting the ion mobility separation, such as modifier types and concentration, separation voltage, and temperature, was systematically investigated. Despite small molecular weight differences among the studied compounds, a good separation was achieved in the ion mobility cell under the optimized conditions, which involved the use of ethanol as a polar gas-phase chemical modifier. Indeed, differential ion mobility was able to resolve (resolution >4) nicotine from its structural isomer anabasine without the use of any chromatographic separation. The quantitative performance of the proposed method was then evaluated, showing satisfactory precision (RSD ≤ 16%) and recoveries ranging from 85 to 100% for nicotine, and from 84 to 126% for the rest of the target analytes. Several commercial electronic cigarette refill liquids were analyzed to demonstrate the applicability of the method. In some cases, significant differences were found between labeled and measured levels of nicotine. Anatabine, cotinine, myosmine, and nornicotine were also found in some of the analyzed samples.

  2. Collision-Induced Dissociation of Deprotonated Peptides. Relative Abundance of Side-Chain Neutral Losses, Residue-Specific Product Ions, and Comparison with Protonated Peptides.

    Science.gov (United States)

    Liang, Yuxue; Neta, Pedatsur; Yang, Xiaoyu; Stein, Stephen E

    2018-03-01

    High-accuracy MS/MS spectra of deprotonated ions of 390 dipeptides and 137 peptides with three to six residues are studied. Many amino acid residues undergo neutral losses from their side chains. The most abundant is the loss of acetaldehyde from threonine. The abundance of losses from the side chains of other amino acids is estimated relative to that of threonine. While some amino acids lose the whole side chain, others lose only part of it, and some exhibit two or more different losses. Side-chain neutral losses are less abundant in the spectra of protonated peptides, being significant mainly for methionine and arginine. In addition to the neutral losses, many amino acid residues in deprotonated peptides produce specific negative ions after peptide bond cleavage. An expanded list of fragment ions from protonated peptides is also presented and compared with those of deprotonated peptides. Fragment ions are mostly different for these two cases. These lists of fragments are used to annotate peptide mass spectral libraries and to aid in the confirmation of specific amino acids in peptides. Graphical Abstract ᅟ.

  3. Relation between the swelling and the disordering in ionic crystals irradiated by fast heavy ions; Relation entre le gonflement et la creation de defauts dans les cristaux ioniques irradies par des ions lourds rapides

    Energy Technology Data Exchange (ETDEWEB)

    Boccanfuso, M

    2001-12-01

    When fast heavy ions penetrate in matter, they slow down essentially by depositing their energy on the electrons. This can lead to strong electronic excitation densities in the solid and then to structural modifications. In this work, calcium fluoride (CaF{sub 2}) was used to look further into the damage induced by irradiation with fast heavy ions in ionic crystals. Four techniques were mainly employed to characterise this damage. These techniques of analysis are wide angle X-ray diffraction, surface profilometry, Rutherford backscattering spectrometry and UV-visible optical absorption spectroscopy. The results of this work show that CaF{sub 2} answers in a multiple way to the electronic excitations. For stopping powers higher than approximately 5 keV/nm, a polygonization seems to occur. This causes a structural disorder, a swelling of 0.27 % and the formation of fractures in the material. A second damage mechanism is caused above approximately 13 keV/nm and results in a loss of the initial crystalline structure. However, optical centres appear whatever the ion stopping power, which indicates that these defects cannot be the cause of the two above mentioned damage mechanisms. According to a thermal spike model, the two thresholds can be linked to melting and sublimation energy of the material, respectively. (author)

  4. ADSORPSI POLUTAN ION DIKROMAT MENGGUNAKAN ZEOLIT ALAM TERMODIFIKASI AMINA (Adsorption of Dichromate Ions Pollutant Using Ammine Modified-Natural Zeolites

    Directory of Open Access Journals (Sweden)

    Eko Sri Kunarti

    2015-11-01

    Full Text Available ABSTRAK Kromium (VI merupakan polutan logam berat berbahaya bagi kesehatan dan lingkungan oleh karena itu pengambilan ion Cr(VI dalam air penting dilakukan untuk mengatasi pencemaran lingkungan. Proses adsorpsi merupakan salah satu teknik sederhana yang dapat digunakan untuk pengambilan ion logam. Pada penelitian ini telah dilakukan kajian adsorpsi ion dikromat sebagai model limbah Cr(VI dalam air menggunakan adsorben zeolit alam termodifikasi amina. Penelitian diawali dengan preparasi adsorben zeolit alam termodifikasi amina. Preparasi dimulai dengan pencucian zeolit alam menggunakan akuades, kemudian refluks zeolit alam menggunakan HCl 3M. Zeolit hasil refluks selanjutnya dimodifikasi menggunakan garam ammonium kuarterner, N-cethyl-N,N,N-trimethylammonium bromide (CTAB dan amina primer, propilamin (PA. Zeolit alam (Z, zeolit teraktivasi asam (ZA dan zeolit hasil modifikasi amina selanjutnya digunakan sebagai adsorben untuk adsorpsi anion dikromat. Karakterisasi adsorben dilakukan dengan mengunakan metode spektroskopi infaramerah dan difraksi sinar-X, sedangkan jumlah anion dikromat yang teradsorpsi dianalisis dengan spektroskopi serapan atom. Hasil penelitian menunjukkan bahwa sampel zeolit mengandung mineral klinoptilolit, mordernit dan kuarsa. Struktur zeolit tidak mengalami kerusakan oleh perlakuan termal dan perlakuan kimia. Modifikasi zeolit meningkatkan efisiensi adsorpsi zeolit alam. Ion dikromat dapat teradsorpsi dengan lebih baik oleh zeolit termodifikasi amina daripada zeolit teraktivasi asam dan zeolit tanpa modifikasi, dengan kemampuan adsorpsi zeolit termodifikasi CTAB (CTAB-Z lebih besar daripada zeolit termodifikasi propilamin (PA-Z. Adsorpsi ion dikromat pada adsorben zeolit berlangsung baik dengan urutan CTAB-Z > PA-Z > ZA > Z, dengan kemampuan adsorpsi masing-masing sebesar 1,96; 1,74; 0,90 dan 0,48 mg/g. Adsorpsi anion dikromat oleh zeolit termodifikasi CTAB merupakan adsorpsi kimia (kemisorpsi dengan energi adsorpsi sebesar

  5. Metal ion attachment to the matrix meso-tetrakis(pentafluorophenyl)porphyrin, related matrices and analytes: an experimental and theoretical study.

    Science.gov (United States)

    van Kampen, Jeroen J A; Luider, Theo M; Ruttink, Paul J A; Burgers, Peter C

    2009-11-01

    In a previous study [van Kampen et al. Analytical Chemistry 2006; 78: 5403], we found that meso-tetrakis (pentafluorophenyl)porphyrin (F20TPP), in combination with lithium salts, provides an efficient matrix to cationize small molecules by Li+ attachment and that this combination can be successfully applied to the quantitative analysis of drugs, such as antiretroviral compounds using matrix-assisted laser desorption ionization in conjunction with a time-of-flight analyzer (MALDI-TOF). In the present study, we further explore the mechanism of metal ion attachment to F20TPP and analytes by MALDI-FTMS(/MS). To this end, we have studied the interaction of F20TPP and analytes with various mono-, di- and trivalent metal ions (Li+, Na+, K+, Rb+, Cs+, Co2+, Cu2+, Zn2+, Fe2+, Fe3+ and Ga3+). For the alkali cations, we find that F20TPP forms complexes only with Li+ and Na+; in addition, model analyte molecules such as poly(ethyleneglycol)s, mixed with F20TPP and the alkali cations, also only form Li+ and Na+ adducts. This contrasts sharply with the commonly used matrix 2,5-dihydroxybenzoic acid, where analytes are most efficiently cationized by Na+ or K+. Reasons for this difference are delineated. Ab initio calculations on porphyrin itself reveal that even the smallest alkali cation, Li+, does not fit in the porphyrin cavity, but lies on top of it, pushing the 21H and 23 H hydrogen atoms out of and below the plane with concomitant bending of the porphyrin skeleton in the opposite direction, i.e. toward the cation. Thus, the Li+ ion is not effectively sequestered and is in fact exposed and thus accessible for donation to analyte molecules. Interaction of F20TPP with di- and trivalent metal ions leads to protoporphyrin-metal ions, where the metal ion is captured within the protoporphyrin dianion cavity. The most intense signal is obtained when F20TPP is reacted with CuCl2 and then subjected to laser ablation. This method presents an easy general route to study the metal

  6. A novel ion imager for secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Matsumoto, Kazuya; Miyata, Kenji; Nakamura, Tsutomu

    1993-01-01

    This paper describes a new area detector for secondary ion mass spectrometry (SIMS) ion microscope, and its performance. The operational principle is based on detecting the change in potential of a floating photodiode caused by the ion-induced secondary-electron emission and the incoming ion itself. The experiments demonstrated that 10 1 -10 5 aluminum ions per pixel can be detected with good linear response. Moreover, relative ion sensitivities from hydrogen to lead were constant within a factor of 2. The performance of this area detector provides the potential for detection of kiloelectronvolt ion images with current ion microscopy

  7. Relation between heat of vaporization, ion transport, molar volume, and cation-anion binding energy for ionic liquids.

    Science.gov (United States)

    Borodin, Oleg

    2009-09-10

    A number of correlations between heat of vaporization (H(vap)), cation-anion binding energy (E(+/-)), molar volume (V(m)), self-diffusion coefficient (D), and ionic conductivity for 29 ionic liquids have been investigated using molecular dynamics (MD) simulations that employed accurate and validated many-body polarizable force fields. A significant correlation between D and H(vap) has been found, while the best correlation was found for -log(DV(m)) vs H(vap) + 0.28E(+/-). A combination of enthalpy of vaporization and a fraction of the cation-anion binding energy was suggested as a measure of the effective cohesive energy for ionic liquids. A deviation of some ILs from the reported master curve is explained based upon ion packing and proposed diffusion pathways. No general correlations were found between the ion diffusion coefficient and molecular volume or the diffusion coefficient and cation/anion binding energy.

  8. Direct evaluation of radiobiological parameters from clinical data in the case of ion beam therapy: an alternative approach to the relative biological effectiveness

    International Nuclear Information System (INIS)

    Cometto, A; Russo, G; Giordanengo, S; Marchetto, F; Cirio, R; Attili, A; Bourhaleb, F; Milian, F M

    2014-01-01

    The relative biological effectiveness (RBE) concept is commonly used in treatment planning for ion beam therapy. Whether models based on in vitro/in vivo RBE data can be used to predict human response to treatments is an open issue. In this work an alternative method, based on an effective radiobiological parameterization directly derived from clinical data, is presented. The method has been applied to the analysis of prostate cancer trials with protons and carbon ions. Prostate cancer trials with proton and carbon ion beams reporting 5 year-local control (LC5) and grade 2 (G2) or higher genitourinary toxicity rates (TOX) were selected from literature to test the method. Treatment simulations were performed on a representative subset of patients to produce dose and linear energy transfer distribution, which were used as explicative physical variables for the radiobiological modelling. Two models were taken into consideration: the microdosimetric kinetic model (MKM) and a linear model (LM). The radiobiological parameters of the LM and MKM were obtained by coupling them with the tumor control probability and normal tissue complication probability models to fit the LC5 and TOX data through likelihood maximization. The model ranking was based on the Akaike information criterion. Results showed large confidence intervals due to the limited variety of available treatment schedules. RBE values, such as RBE = 1.1 for protons in the treated volume, were derived as a by-product of the method, showing a consistency with current approaches. Carbon ion RBE values were also derived, showing lower values than those assumed for the original treatment planning in the target region, whereas higher values were found in the bladder. Most importantly, this work shows the possibility to infer the radiobiological parametrization for proton and carbon ion treatment directly from clinical data. (paper)

  9. Electronic structure and related properties of ferrocyanide ion calculated by the SCF Xα-scattered wave method

    International Nuclear Information System (INIS)

    Guenzburger, D.; Maffeo, B.; Siqueira, M.L. de

    1975-08-01

    The SCF-XαSW method is used to calculate the electronic structure of the ferrocyanide ion. Optical transitions and X-Ray photoelectron emission are obtained from the energy level scheme and compared with experimental results. The charge density in the Fe nucleus is also computed and the result is correlated with isomer shift measurements made on this and other Fe complexes for which theoretical calculations have been performed

  10. Solutions to defect-related problems in implanted silicon by controlled injection of vacancies by high-energy ion irradiation

    International Nuclear Information System (INIS)

    Roth, E.G.; Holland, O.W.; Duggan, J.L.

    1999-01-01

    Amorphization and a dual implant technique have been used to manipulate residual defects that persist following implantation and post-implant thermal treatments. Residual defects can often be attributed to ion-induced defect excesses. A defect is considered to be excess when it occurs in a localized region at a concentration greater than its complement. Sources of excess defects include spatially separated Frenkel pairs, excess interstitials resulting from the implanted atoms, and sputtering. Preamorphizing prior to dopant implantation has been proposed to eliminate dopant broadening due to ion channeling as well as dopant diffusion during subsequent annealing. However, transient-enhanced diffusion (TED) of implanted boron has been observed in pre-amorphized Si. The defects driving this enhanced boron diffusion are thought to be the extended interstitial-type defects that form below the amorphous-crystalline interface during implantation. A dual implantation process was applied in an attempt to reduce or eliminate this interfacial defect band. High-energy, ion implantation is known to inject a vacancy excess in this region. Vacancies were implanted at a concentration coincident with the excess interstitials below the a-c interface to promote recombination between the two defect species. Preliminary results indicate that a critical fluence, i.e., a sufficient vacancy concentration, will eliminate the interstitial defects. The effect of the reduction or elimination of these interfacial defects upon TED of boron will be discussed. Rutherford backscattering/channeling and cross section transmission electron microscopy analyses were used to characterize the defect structure within the implanted layer. Secondary ion mass spectrometry was used to profile the dopant distributions. copyright 1999 American Institute of Physics

  11. Ion implantation

    International Nuclear Information System (INIS)

    Dearnaley, Geoffrey

    1975-01-01

    First, ion implantation in semiconductors is discussed: ion penetration, annealing of damage, gettering, ion implanted semiconductor devices, equipement requirements for ion implantation. The importance of channeling for ion implantation is studied. Then, some applications of ion implantation in metals are presented: study of the corrosion of metals and alloys; influence or ion implantation on the surface-friction and wear properties of metals; hyperfine interactions in implanted metals

  12. Quantitative approach to relate dielectric constant studies with TSDC studies of 50 MeV Si ion irradiated kapton-H polymide

    International Nuclear Information System (INIS)

    Quamara, J.K.; Garg, Maneesha; Sridharbabu, Y.; Prabhavathi, T.

    2003-01-01

    Temperature and frequency dependent dielectric behaviour has been investigated for pristine and swift heavy ion irradiated (Si ion, 50 MeV energy) kapton-H polyimide in the temperature range of 30 to 250 deg C at frequencies 120 Hz, 1 kHz, 10 kHz and 100 kHz respectively. The dielectric relaxation behaviour of the same samples was also studied using thermally stimulated discharge current (TSDC) technique. A quantitative approach is developed using a well-known Clausius Mossotti equation to relate the TSDC findings to the dielectric constant studies. An overall increase in the dielectric constant of the irradiated samples are also in conformity to the TSDC findings. (author)

  13. Determination of relative populations of the magnetic sub-levels of the 4 1D level of HeI excited by heavy ion impact

    International Nuclear Information System (INIS)

    Carre, M.; Zgainski, A.; Gaillard, M.; Nouh, M.; Lombardi, M.

    1981-01-01

    The theoretical study of the depolarization of a transition, emitted from an excited atomic level J = 2, by a static electric field leads to the development of a new experimental method and the measurement of the relative population of the Zeeman sub-levels. This method is applied to the study of the 4 1 D level of HeI excited by several heavy ions (Li + , Ne + , Na + and Mg + ) at intermediate energy between 6 and 40 keV. From the obtained results, we derive informations on the target excitation phenomena: in particular present evidence for a long-range interaction, due to the ion charge, in the output channel of the collision [fr

  14. Transport of radioactive ion beams and related safety issues: The {sup 132}Sn{sup +} case study

    Energy Technology Data Exchange (ETDEWEB)

    Osswald, F., E-mail: francis.osswald@iphc.cnrs.fr; Bouquerel, E.; Boutin, D.; Dinkov, A.; Sellam, A. [IPHC/IN2P3/CNRS, University of Strasbourg, 67037 Strasbourg (France); Kazarinov, N. [JINR/FLNR, 141980 Dubna (Russian Federation); Perrot, L. [IPNO/IN2P3/CNRS, University of Paris-Sud-11, 91406 Orsay (France)

    2014-12-15

    The transport of intense radioactive ion beam currents requires a careful design in order to limit the beam losses, the contamination and thus the dose rates. Some investigations based on numerical models and calculations have been performed in the framework of the SPIRAL 2 project to evaluate the performance of a low energy beam transport line located between the isotope separation on line (ISOL) production cell and the experiment areas. The paper presents the results of the transverse phase-space analysis, the beam losses assessment, the resulting contamination, and radioactivity levels. They show that reasonable beam transmission, emittance growth, and dose rates can be achieved considering the current standards.

  15. Characterization of the interaction between therapeutical carbon ions and bone-like materials and related impact on treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Eichhorn, Anna; Durante, Marco [GSI Helmholtzzentrum fuer Schwereionen, Darmstadt (Germany); TU Darmstadt (Germany); Carlino, Antonio [University of Palermo (Italy); Kaderka, Robert; Kraemer, Michael; La Tessa, Chiara; Scifoni, Emanuele [GSI Helmholtzzentrum fuer Schwereionen, Darmstadt (Germany)

    2013-07-01

    Radiotherapy is one of the most common and effective therapies for cancer. The treatment planning system for ions TRiP98 was developed at GSI, Darmstadt. In TRiP98, the interaction between primary radiation and tissue is modeled from experimental data measured in water and rescaled to other tissue. This approximation is not accurate enough for biological materials whose elemental composition besides density deviates significantly from water. The nuclear attenuation of carbon beams in bone-like materials was measured and an estimation of the fragmentation cross section was done. In parallel, the dose profile inhomogeneity predicted by TRiP98 at the interface between water and bones was investigated and measured at HIT (Heidelberg). A 3D treatment plan was delivered in a water phantom equipped with bone targets. Pin-point ionization chambers and X-ray dosimetric films were used for measuring the dose at different positions. As a further step, the measured cross sections of carbon ions in bone have been implemented in TRiP98. The comparison of the dose profiles calculated with the standard and benchmarked versions of the treatment planning will give an estimate of the improvement.

  16. Numerical simulation and experimental validation of the three-dimensional flow field and relative analyte concentration distribution in an atmospheric pressure ion source.

    Science.gov (United States)

    Poehler, Thorsten; Kunte, Robert; Hoenen, Herwart; Jeschke, Peter; Wissdorf, Walter; Brockmann, Klaus J; Benter, Thorsten

    2011-11-01

    In this study, the validation and analysis of steady state numerical simulations of the gas flows within a multi-purpose ion source (MPIS) are presented. The experimental results were obtained with particle image velocimetry (PIV) measurements in a non-scaled MPIS. Two-dimensional time-averaged velocity and turbulent kinetic energy distributions are presented for two dry gas volume flow rates. The numerical results of the validation simulations are in very good agreement with the experimental data. All significant flow features have been correctly predicted within the accuracy of the experiments. For technical reasons, the experiments were conducted at room temperature. Thus, numerical simulations of ionization conditions at two operating points of the MPIS are also presented. It is clearly shown that the dry gas volume flow rate has the most significant impact on the overall flow pattern within the APLI source; far less critical is the (larger) nebulization gas flow. In addition to the approximate solution of Reynolds-Averaged Navier-Stokes equations, a transport equation for the relative analyte concentration has been solved. The results yield information on the three-dimensional analyte distribution within the source. It becomes evident that for ion transport into the MS ion transfer capillary, electromagnetic forces are at least as important as fluid dynamic forces. However, only the fluid dynamics determines the three-dimensional distribution of analyte gas. Thus, local flow phenomena in close proximity to the spray shield are strongly impacting on the ionization efficiency.

  17. The relative biological effectiveness for carbon and oxygen ion beams using the raster-scanning technique in hepatocellular carcinoma cell lines.

    Directory of Open Access Journals (Sweden)

    Daniel Habermehl

    Full Text Available BACKGROUND: Aim of this study was to evaluate the relative biological effectiveness (RBE of carbon (12C and oxygen ion (16O-irradiation applied in the raster-scanning technique at the Heidelberg Ion beam Therapy center (HIT based on clonogenic survival in hepatocellular carcinoma cell lines compared to photon irradiation. METHODS: Four human HCC lines Hep3B, PLC, HepG2 and HUH7 were irradiated with photons, 12C and 16O using a customized experimental setting at HIT for in-vitro trials. Cells were irradiated with increasing physical photon single doses of 0, 2, 4 and 6 Gy and heavy ion-single doses of 0, 0.125, 0.5, 1, 2, 3 Gy (12C and 16O. SOBP-penetration depth and extension was 35 mm +/-4 mm and 36 mm +/-5 mm for carbon ions and oxygen ions respectively. Mean energy level and mean linear energy transfer (LET were 130 MeV/u and 112 keV/um for 12C, and 154 MeV/u and 146 keV/um for 16O. Clonogenic survival was computated and relative biological effectiveness (RBE values were defined. RESULTS: For all cell lines and both particle modalities α- and β-values were determined. As expected, α-values were significantly higher for 12C and 16O than for photons, reflecting a steeper decline of the initial slope of the survival curves for high-LET beams. RBE-values were in the range of 2.1-3.3 and 1.9-3.1 for 12C and 16O, respectively. CONCLUSION: Both irradiation with 12C and 16O using the raster-scanning technique leads to an enhanced RBE in HCC cell lines. No relevant differences between achieved RBE-values for 12C and 16O were found. Results of this work will further influence biological-adapted treatment planning for HCC patients that will undergo particle therapy with 12C or 16O.

  18. Relative Biological Effectiveness of Energetic Heavy Ions for Intestinal Tumorigenesis Shows Male Preponderance and Radiation Type and Energy Dependence in APC{sup 1638N/+} Mice

    Energy Technology Data Exchange (ETDEWEB)

    Suman, Shubhankar; Kumar, Santosh; Moon, Bo-Hyun; Strawn, Steve J.; Thakor, Hemang; Fan, Ziling [Department of Biochemistry and Molecular & Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia (United States); Shay, Jerry W. [Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas (United States); Fornace, Albert J. [Department of Biochemistry and Molecular & Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia (United States); Center of Excellence in Genomic Medicine Research (CEGMR), King Abdulaziz University, Jeddah (Saudi Arabia); Datta, Kamal, E-mail: kd257@georgetown.edu [Department of Biochemistry and Molecular & Cellular Biology and Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia (United States)

    2016-05-01

    Purpose: There are uncertainties associated with the prediction of colorectal cancer (CRC) risk from highly energetic heavy ion (HZE) radiation. We undertook a comprehensive assessment of intestinal and colonic tumorigenesis induced after exposure to high linear energy transfer (high-LET) HZE radiation spanning a range of doses and LET in a CRC mouse model and compared the results with the effects of low-LET γ radiation. Methods and Materials: Male and female APC{sup 1638N/+} mice (n=20 mice per group) were whole-body exposed to sham-radiation, γ rays, {sup 12}C, {sup 28}Si, or {sup 56}Fe radiation. For the >1 Gy HZE dose, we used γ-ray equitoxic doses calculated using relative biological effectiveness (RBE) determined previously. The mice were euthanized 150 days after irradiation, and intestinal and colon tumor frequency was scored. Results: The highest number of tumors was observed after {sup 28}Si, followed by {sup 56}Fe and {sup 12}C radiation, and tumorigenesis showed a male preponderance, especially after {sup 28}Si. Analysis showed greater tumorigenesis per unit of radiation (per cGy) at lower doses, suggesting either radiation-induced elimination of target cells or tumorigenesis reaching a saturation point at higher doses. Calculation of RBE for intestinal and colon tumorigenesis showed the highest value with {sup 28}Si, and lower doses showed greater RBE relative to higher doses. Conclusions: We have demonstrated that the RBE of heavy ion radiation-induced intestinal and colon tumorigenesis is related to ion energy, LET, gender, and peak RBE is observed at an LET of 69 keV/μm. Our study has implications for understanding risk to astronauts undertaking long duration space missions.

  19. Cell organisation, sulphur metabolism and ion transport-related genes are differentially expressed in Paracoccidioides brasiliensis mycelium and yeast cells

    Directory of Open Access Journals (Sweden)

    Passos Geraldo AS

    2006-08-01

    Full Text Available Abstract Background Mycelium-to-yeast transition in the human host is essential for pathogenicity by the fungus Paracoccidioides brasiliensis and both cell types are therefore critical to the establishment of paracoccidioidomycosis (PCM, a systemic mycosis endemic to Latin America. The infected population is of about 10 million individuals, 2% of whom will eventually develop the disease. Previously, transcriptome analysis of mycelium and yeast cells resulted in the assembly of 6,022 sequence groups. Gene expression analysis, using both in silico EST subtraction and cDNA microarray, revealed genes that were differential to yeast or mycelium, and we discussed those involved in sugar metabolism. To advance our understanding of molecular mechanisms of dimorphic transition, we performed an extended analysis of gene expression profiles using the methods mentioned above. Results In this work, continuous data mining revealed 66 new differentially expressed sequences that were MIPS(Munich Information Center for Protein Sequences-categorised according to the cellular process in which they are presumably involved. Two well represented classes were chosen for further analysis: (i control of cell organisation – cell wall, membrane and cytoskeleton, whose representatives were hex (encoding for a hexagonal peroxisome protein, bgl (encoding for a 1,3-β-glucosidase in mycelium cells; and ags (an α-1,3-glucan synthase, cda (a chitin deacetylase and vrp (a verprolin in yeast cells; (ii ion metabolism and transport – two genes putatively implicated in ion transport were confirmed to be highly expressed in mycelium cells – isc and ktp, respectively an iron-sulphur cluster-like protein and a cation transporter; and a putative P-type cation pump (pct in yeast. Also, several enzymes from the cysteine de novo biosynthesis pathway were shown to be up regulated in the yeast form, including ATP sulphurylase, APS kinase and also PAPS reductase. Conclusion Taken

  20. Discussion on resin conversion related problems in the process of using ion exchange method to recover uranium from carbonate lixivium in a uranium mine

    International Nuclear Information System (INIS)

    Yu Suqin; Du Yuhai; Long Qing; Han Wei; Que Weimin

    2012-01-01

    Ion exchange method was used to recover uranium from carbonate lixivium in a uranium mine, lean resin was converted by sodium bicarbonate solution. Because of high sodium bicarbonate, chlorine and uranium concentration in the converted solution, it is difficult to effectively use. Combined with the production practices of the mine, the resin conversion related problems were analyzed. Some measures were taken for improving utilization rate of the converted solution, and good results were obtained. The utilization rate of the converted solution increased to about 20% from less than lO%, and the consumption of sodium bicarbonate reduced by about 30%. (authors)

  1. Ion implantation into iron

    International Nuclear Information System (INIS)

    Iwaki, Masaya

    1978-01-01

    The distribution of implanted ions in iron, the friction characteristics and the corrosion of iron were studied. The distribution of Ni or Cr ions implanted into mild steel was measured. The accelerated voltage was 150 keV, and the beam current density was about 2 microampere/cm 2 . The measurement was made with an ion microanalyzer. The measured distribution was compared with that of LSS theory. Deep invasion of Ni was seen in the measured distribution. The distribution of Cr ions was different from the distribution calculated by the LSS theory. The relative friction coefficient of mild steel varied according to the dose of implanted Cu or N ions, and to the accelerating voltage. Formation of compound metals on the surfaces of metals by ion-implantation was investigated for the purpose to prevent the corrosion of metals. The resistance of mild steel in which Ni ions were implanted was larger than that of mild steel without any treatment. (Kato, T.)

  2. DNA-based Nanoconstructs for the Detection of Ions and Biomolecules with Related Raman/SERS Signature Studies

    Science.gov (United States)

    Brenneman, Kimber L.

    The utilization of DNA aptamers and semiconductor quantum dots (QDs) for the detection of ions and biomolecules was investigated. In recent years, there have been many studies based on the use of DNA and RNA aptamers, which are single stranded oligonucleotides capable of binding to biomolecules, other molecules, and ions. In many of these cases, the conformational changes of these DNA and RNA aptamers are suitable to use fluorescence resonant energy transfer (FRET) or nanometal surface energy transfer (NSET) techniques to detect such analytes. Coupled with this growth in such uses of aptamers, there has been an expanded use of semiconductor quantum dots as brighter, longer-lasting alternatives to fluorescent dyes in labeling and detection techniques of interest in biomedicine and environmental monitoring. Thrombin binding aptamer (TBA) and a zinc aptamer were used to detect mercury, lead, zinc, and cadmium. These probes were tested in a liquid assay as well as on a filter paper coupon. Biomolecules were also studied and detected using surface-enhanced Raman spectroscopy (SERS), including DNA aptamers and C-reactive protein (CRP). Raman spectroscopy is a useful tool for sensor development, label-free detection, and has the potential for remote sensing. Raman spectra provide information on the vibrational modes or phonons, between and within molecules. Therefore, unique spectral fingerprints for single molecules can be obtained. SERS is accomplished through the use of substrates with nanometer scale geometries made of metals with many free electrons, such as silver, gold, or copper. In this research silver SERS substrates were used to study the SERS signature of biomolecules that typically produce very weak Raman signals.

  3. Ion-Ion Plasmas Produced by Electron Beams

    Science.gov (United States)

    Fernsler, R. F.; Leonhardt, D.; Walton, S. G.; Meger, R. A.

    2001-10-01

    The ability of plasmas to etch deep, small-scale features in materials is limited by localized charging of the features. The features charge because of the difference in electron and ion anisotropy, and thus one solution now being explored is to use ion-ion plasmas in place of electron-ion plasmas. Ion-ion plasmas are effectively electron-free and consist mainly of positive and negative ions. Since the two ion species behave similarly, localized charging is largely eliminated. However, the only way to produce ion-ion plasmas at low gas pressure is to convert electrons into negative ions through two-body attachment to neutrals. While the electron attachment rate is large at low electron temperatures (Te < 1 eV) in many of the halogen gases used for processing, these temperatures occur in most reactors only during the afterglow when the heating fields are turned off and the plasma is decaying. By contrast, Te is low nearly all the time in plasmas produced by electron beams, and therefore electron beams can potentially produce ion-ion plasmas continuously. The theory of ion-ion plasmas formed by pulsed electron beams is examined in this talk and compared with experimental results presented elsewhere [1]. Some general limitations of ion-ion plasmas, including relatively low flux levels, are discussed as well. [1] See the presentation by D. Leonhardt et al. at this conference.

  4. Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Philip A., E-mail: Smith.Philip.A@dol.gov [Uniformed Services University of the Health Sciences, Department of Preventive Medicine and Biometrics, 4301 Jones Bridge Road, Bethesda, MD, 20814 (United States); Lepage, Carmela R. Jackson [Defence R and D Canada - Suffield, Box 400, Station Main, Medicine Hat, Alberta, T1A 8K6 (Canada); Savage, Paul B. [Brigham Young University, Department of Chemistry and Biochemistry, Provo, UT, 84602 (United States); Bowerbank, Christopher R.; Lee, Edgar D. [Torion Technologies Inc., 796 East Utah Valley Drive, Suite 200, American Fork, UT, 84003 (United States); Lukacs, Michael J. [Defence R and D Canada - Suffield, Box 400, Station Main, Medicine Hat, Alberta, T1A 8K6 (Canada)

    2011-04-01

    The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H]{sup +}) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H]{sup +} ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d{sub 15} provided evidence that [M+H]{sup +} production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H]{sup +} ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

  5. Use of a hand-portable gas chromatograph-toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

    International Nuclear Information System (INIS)

    Smith, Philip A.; Lepage, Carmela R. Jackson; Savage, Paul B.; Bowerbank, Christopher R.; Lee, Edgar D.; Lukacs, Michael J.

    2011-01-01

    The chemical warfare agent O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX) and many related degradation products produce poorly diagnostic electron ionization (EI) mass spectra by transmission quadrupole mass spectrometry. Thus, chemical ionization (CI) is often used for these analytes. In this work, pseudomolecular ([M+H] + ) ion formation from self-chemical ionization (self-CI) was examined for four VX degradation products containing the diisopropylamine functional group. A person-portable toroidal ion trap mass spectrometer with a gas chromatographic inlet was used with EI, and both fixed-duration and feedback-controlled ionization time. With feedback-controlled ionization, ion cooling (reaction) times and ion formation target values were varied. Evidence for protonation of analytes was observed under all conditions, except for the largest analyte, bis(diisopropylaminoethyl)disulfide which yielded [M+H] + ions only with increased fixed ionization or ion cooling times. Analysis of triethylamine-d 15 provided evidence that [M+H] + production was likely due to self-CI. Analysis of a degraded VX sample where lengthened ion storage and feedback-controlled ionization time were used resulted in detection of [M+H] + ions for VX and several relevant degradation products. Dimer ions were also observed for two phosphonate compounds detected in this sample.

  6. Rotational and translational dynamics and their relation to hydrogen bond lifetimes in an ionic liquid by means of NMR relaxation time experiments and molecular dynamics simulation

    Science.gov (United States)

    Strate, Anne; Neumann, Jan; Overbeck, Viviane; Bonsa, Anne-Marie; Michalik, Dirk; Paschek, Dietmar; Ludwig, Ralf

    2018-05-01

    We report a concerted theoretical and experimental effort to determine the reorientational dynamics as well as hydrogen bond lifetimes for the doubly ionic hydrogen bond +OH⋯O- in the ionic liquid (2-hydroxyethyl)trimethylammonium bis(trifluoromethylsulfonyl)imide [Ch][NTf2] by using a combination of NMR relaxation time experiments, density functional theory (DFT) calculations, and molecular dynamics (MD) simulations. Due to fast proton exchange, the determination of rotational correlation times is challenging. For molecular liquids, 17O-enhanced proton relaxation time experiments have been used to determine the rotational correlation times for the OH vectors in water or alcohols. As an alternative to those expensive isotopic substitution experiments, we employed a recently introduced approach which is providing access to the rotational dynamics from a single NMR deuteron quadrupolar relaxation time experiment. Here, the deuteron quadrupole coupling constants (DQCCs) are obtained from a relation between the DQCC and the δ1H proton chemical shifts determined from a set of DFT calculated clusters in combination with experimentally determined proton chemical shifts. The NMR-obtained rotational correlation times were compared to those obtained from MD simulations and then related to viscosities for testing the applicability of popular hydrodynamic models. In addition, hydrogen bond lifetimes were derived, using hydrogen bond population correlation functions computed from MD simulations. Here, two different time domains were observed: The short-time contributions to the hydrogen lifetimes and the reorientational correlation times have roughly the same size and are located in the picosecond range, whereas the long-time contributions decay with relaxation times in the nanosecond regime and are related to rather slow diffusion processes. The computed average hydrogen bond lifetime is dominated by the long-time process, highlighting the importance and longevity of

  7. Imaging and relative quantification of 127I in human thyroid follicles by analytical ion microscope: Characterization of benign thyroid epithelial tumors

    International Nuclear Information System (INIS)

    Fragu, P.; Briancon, C.; Noel, M.; Halpern, S.

    1989-01-01

    Analytical ion microscopy (AIM) can be used for imaging and relative quantification of chemical elements in tissue sections. We used this technique to assess the changes in 127I mapping within thyroid follicular cells and follicular lumina in benign thyroid epithelial abnormalities from 17 patients and in macroscopically normal perinodular tissue surrounding solitary cold nodules from 8 patients. Among the 17 patients, 9 had simple goiters, 5 had toxic nodular goiters, and 3 had hypofunctioning (cold) nodules. The tissue samples were fixed chemically and embedded in methacrylate resin to ensure preservation of organified iodine, and thin sections were analyzed by AIM. 127I was found in the follicular lumina and follicular epithelial cells of most specimens. The local concentration of 127I, which is proportional to the ratio of the two secondary ion beam currents of iodine and carbon, was evaluated in 30 follicular lumina and 30 follicular epithelial cells of each specimen. In normal tissue, the relative 127I concentration within follicular cells (mean, 0.72; range 0.01-8.30) was much lower than that in follicular lumina (mean, 4.63; range, 0.18-36.74). In simple goiter tissue, follicular lumen (mean, 0.57; range, 0.00-5.76), and cell (mean, 0.17; range, 0.002-1.82) relative 127I concentrations were below normal, but both distributions remained different. On the contrary, in toxic nodular goiter tissue the follicular cell relative 127I concentration (mean, 0.96; range, 0.003-27.3) largely overlapped that of the follicular lumina (mean, 2.1; range, 0.001-36.5). The cold nodules had the lowest relative follicular lumina 127I concentration (mean, 0.008; range, undetectable-0.07), and the relative cellular 127I concentrations were undetectable in 67%. These results demonstrate the capacity of AIM to characterize the functional activity of thyroid tissue without prior administration of radio-iodine

  8. The effects of correlation, relativity, quantum electrodynamics, nuclear size and parity non-conservation in alkali atoms and alkali-like ions

    International Nuclear Information System (INIS)

    Tiwary, S.N.

    1995-01-01

    The present review briefly presents the growing experimental as well as theoretical interests in recent years in the effects of (1) correlation, (2) relativity, (3) quantum electrodynamic (QED), (4) finite nuclear size (FNS) and (5) parity non-conservation (PNC) on the high precision electronic structure of alkali atoms and alkali-like ions. Many high precision experiments have been performed which need very high accurate theoretical prediction for correct interpretation and identification of different physical effects involved. Some experiments separate these effects and some do not. Several sophisticated theoretical techniques have been developed for corrections of these effects which play an extremely important role in order to obtain results of high accuracy to well below 1% level and to understand experimental observations of high precision. Correlation, relativity and finite nuclear size effects have been treated on an equal footing in some theoretical methods but QED and PNC have been calculated separately. At present, there is no theory which accounts all five effects in a coherent and unified manner. Future challenges and directions, in reliable structure calculations in atoms and ions, have been discussed and suggested. (author). 83 refs, 3 figs, 9 tabs

  9. Lithium ion batteries (NMC/graphite) cycling at 80 °C: Different electrolytes and related degradation mechanism

    Science.gov (United States)

    Genieser, R.; Ferrari, S.; Loveridge, M.; Beattie, S. D.; Beanland, R.; Amari, H.; West, G.; Bhagat, R.

    2018-01-01

    A comprehensive study on high temperature cycling (80 °C) of industrial manufactured Li-ion pouch cells (NMC-111/Graphite) filled with different electrolytes is introduced. Ageing processes such as capacity fade, resistance increase and gas generation are reduced by the choice of appropriate electrolyte formulations. However, even by using additive formulations designed for elevated temperatures a large resistance increase is observed after 200 cycles and more (which does not happen at 55 °C). Symmetrical EIS (Electrochemical Impedance Spectroscopy) shows that the cathodic charge transfer resistance is the main reason for this behaviour. Nonetheless most of the active Li is still available when cycling with suitable additives. No change of the cathode crystalline structure or a growth of the cathodic surface reconstruction layer is observed post cycling at 80 °C. Therefore a disintegration of NMC secondary particles is believed to be the main reason of the cell failure. A separation of single grains is leading to new decomposition and reconstruction layers between primary particles and an increased charge transfer resistance. Further approaches to improve the high temperature cycle stability of NMC based materials should therefore be aimed at the cathode particles morphology in combination with similar electrolyte formulations as used in this study.

  10. Acid-sensing ion channels contribute to chemosensitivity of breathing-related neurons of the nucleus of the solitary tract.

    Science.gov (United States)

    Huda, Rafiq; Pollema-Mays, Sarah L; Chang, Zheng; Alheid, George F; McCrimmon, Donald R; Martina, Marco

    2012-10-01

    Cellular mechanisms of central pH chemosensitivity remain largely unknown. The nucleus of the solitary tract (NTS) integrates peripheral afferents with central pathways controlling breathing; NTS neurons function as central chemosensors, but only limited information exists concerning the ionic mechanisms involved. Acid-sensing ion channels (ASICs) mediate chemosensitivity in nociceptive terminals, where pH values ∼6.5 are not uncommon in inflammation, but are also abundantly expressed throughout the brain where pHi s tightly regulated and their role is less clear. Here we test the hypothesis that ASICs are expressed in NTS neurons and contribute to intrinsic chemosensitivity and control of breathing. In electrophysiological recordings from acute rat NTS slices, ∼40% of NTS neurons responded to physiological acidification (pH 7.0) with a transient depolarization. This response was also present in dissociated neurons suggesting an intrinsic mechanism. In voltage clamp recordings in slices, a pH drop from 7.4 to 7.0 induced ASIC-like inward currents (blocked by 100 μM amiloride) in ∼40% of NTS neurons, while at pH ≤ 6.5 these currents were detected in all neurons tested; RT-PCR revealed expression of ASIC1 and, less abundantly, ASIC2 in the NTS. Anatomical analysis of dye-filled neurons showed that ASIC-dependent chemosensitive cells (cells responding to pH 7.0) cluster dorsally in the NTS. Using in vivo retrograde labelling from the ventral respiratory column, 90% (9/10) of the labelled neurons showed an ASIC-like response to pH 7.0, suggesting that ASIC currents contribute to control of breathing. Accordingly, amiloride injection into the NTS reduced phrenic nerve activity of anaesthetized rats with an elevated arterial P(CO(2)) .

  11. Surfactant-assisted sol gel preparation of high-surface area mesoporous TiO2 nanocrystalline Li-ion battery anodes

    International Nuclear Information System (INIS)

    Casino, S.; Di Lupo, F.; Francia, C.; Tuel, A.; Bodoardo, S.; Gerbaldi, C.

    2014-01-01

    Highlights: • Mesoporous TiO 2 nanocrystalline lithium battery anodes with tunable morphology. • Simple sol–gel technique using different cationic surfactants is adopted. • Textural/morphological characteristics define the electrochemical behaviour. • TiO 2 anatase using C16TAB exhibits stable performance after 200 cycles. • It shows promising prospects as high-voltage safe Li-ion battery anode. - Abstract: We here investigate the physico-chemical/morphological characteristics and cycling behaviour of several kinds of nanocrystalline TiO 2 Li-ion battery anodes selectively prepared through a simple sol–gel strategy based on a low-cost titanium oxysulfate precursor, by mediation of different cationic surfactants having different features (e.g., chain lengths, counter ion, etc.): i.e., cetyl-trimethylammonium bromide (CTAB), cetyl-trimethylammonium chloride (CTAC), benzalkonium chloride (BC) or octadecyl-trimethyl ammonium bromide (C 18 TAB). X-ray diffraction profiles reveal single phase anatase having good correspondence with the reference pattern when using short chain CTAB, while in the other cases the presence of chloride and/or an increased chain length affect the purity of the samples. FESEM analysis reveal nanosized particles forming cauliflower-like aggregates. TiO 2 materials demonstrate mesoporous characteristics and large specific surface area ranging from 250 to 30 m 2 g −1 . Remarkably stable electrode performance are achieved by appropriately selecting the cationic surfactant and the surfactant/precursor ratio. Detailed analysis is provided on the effect of the reaction conditions upon the formation of mesoporous crystalline titania enlightening new directions for the development of high performing lithium storage electrodes by a simple and low cost sol–gel strategy

  12. Surfactant-assisted sol gel preparation of high-surface area mesoporous TiO{sub 2} nanocrystalline Li-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Casino, S. [GAME Lab, Department of Applied Science and Technology – DISAT, Institute of Chemistry, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Di Lupo, F., E-mail: francesca.dilupo@polito.it [GAME Lab, Department of Applied Science and Technology – DISAT, Institute of Chemistry, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Francia, C. [GAME Lab, Department of Applied Science and Technology – DISAT, Institute of Chemistry, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Tuel, A. [IRCELYON, Institut de Recherches sur la Catalyse et l’environnement de Lyon, UMR 5256, CNRS-Université de Lyon 1, 2 Avenue Albert Einstein, 69626 Villeurbanne Cedex (France); Bodoardo, S. [GAME Lab, Department of Applied Science and Technology – DISAT, Institute of Chemistry, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Gerbaldi, C., E-mail: claudio.gerbaldi@polito.it [GAME Lab, Department of Applied Science and Technology – DISAT, Institute of Chemistry, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy)

    2014-05-01

    Highlights: • Mesoporous TiO{sub 2} nanocrystalline lithium battery anodes with tunable morphology. • Simple sol–gel technique using different cationic surfactants is adopted. • Textural/morphological characteristics define the electrochemical behaviour. • TiO{sub 2} anatase using C16TAB exhibits stable performance after 200 cycles. • It shows promising prospects as high-voltage safe Li-ion battery anode. - Abstract: We here investigate the physico-chemical/morphological characteristics and cycling behaviour of several kinds of nanocrystalline TiO{sub 2} Li-ion battery anodes selectively prepared through a simple sol–gel strategy based on a low-cost titanium oxysulfate precursor, by mediation of different cationic surfactants having different features (e.g., chain lengths, counter ion, etc.): i.e., cetyl-trimethylammonium bromide (CTAB), cetyl-trimethylammonium chloride (CTAC), benzalkonium chloride (BC) or octadecyl-trimethyl ammonium bromide (C{sub 18}TAB). X-ray diffraction profiles reveal single phase anatase having good correspondence with the reference pattern when using short chain CTAB, while in the other cases the presence of chloride and/or an increased chain length affect the purity of the samples. FESEM analysis reveal nanosized particles forming cauliflower-like aggregates. TiO{sub 2} materials demonstrate mesoporous characteristics and large specific surface area ranging from 250 to 30 m{sup 2} g{sup −1}. Remarkably stable electrode performance are achieved by appropriately selecting the cationic surfactant and the surfactant/precursor ratio. Detailed analysis is provided on the effect of the reaction conditions upon the formation of mesoporous crystalline titania enlightening new directions for the development of high performing lithium storage electrodes by a simple and low cost sol–gel strategy.

  13. Lithium-ion batteries

    CERN Document Server

    Yoshio, Masaki; Kozawa, Akiya

    2010-01-01

    This book is a compilation of up-to-date information relative to Li-Ion technology. It provides the reader with a single source covering all important aspects of Li-Ion battery operations. It fills the gap between the old original Li-Ion technology and present state of the technology that has developed into a high state of practice. The book is designed to provide a single source for an up-to-date description of the technology associated with the Li-Ion battery industry. It will be useful to researchers interested in energy conversion for the direct conversion of chemical energy into electrica

  14. High brightness ion source

    International Nuclear Information System (INIS)

    Dreyfus, R.W.; Hodgson, R.T.

    1975-01-01

    A high brightness ion beam is obtainable by using lasers to excite atoms or molecules from the ground state to an ionized state in increments, rather than in one step. The spectroscopic resonances of the atom or molecule are used so that relatively long wavelength, low power lasers can be used to obtain such ion beam

  15. Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities

    International Nuclear Information System (INIS)

    Mark, J.W.K.

    1982-01-01

    Within the last few years, there have also appeared in the Heavy-Ion Fusion literature several studies of targets which have outer tampers. One-dimensional simulations indicate higher target gains with a judicious amount of tamping. But for these targets, a full investigation has not been carried through in regards to conservative criteria for fluid instabilities as well as reasonable imperfections in target fabrication and illumination symmetry which all affect target ignition and burn. Comparisons of these results with the gain survey of Part I would have to be performed with care. These calculations suggest that experiments relating to high temperature disk heating, as well as beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics

  16. Range-energy relation, range straggling and response function of CsI(Tl), BGO and GSO(Ce) scintillators for light ions

    CERN Document Server

    Avdeichikov, V; Jakobsson, B; Rodin, A M; Ter-Akopian, G M

    2000-01-01

    Range-energy relations and range straggling of sup 1 sup , sup 2 sup , sup 3 H and sup 4 sup , sup 6 He isotopes with the energy approx 50A MeV are measured for the CsI(Tl), BGO and GSO(Ce) scintillators with an accuracy better than 0.2% and 5%, respectively. The Si-Sci/PD telescope was exposed to secondary beams from the mass separator ACCULINNA. The experimental technique is based on the registration of the 'jump' in the amplitude of the photodiode signal for ions passing through the scintillation crystal. Light response of the scintillators for ions 1<=Z<=4 is measured in energy range (5-50)A MeV, the results are in good agreement with calculations based on Birks model. The energy loss straggling for particles with DELTA E/E=0.01-0.50 and mass up to A=10 in 286 mu m DELTA E silicon detector is studied and compared with theoretical prescriptions. The results allow a precise absolute calibration of the scintillation crystal and to optimize the particle identification by the DELTA E-E(Sci/PD) method.

  17. Profiles of cortical tissue depolarization in cat focal cerebral ischemia in relation to calcium ion homeostasis and nitric oxide production.

    Science.gov (United States)

    Ohta, K; Graf, R; Rosner, G; Heiss, W D

    1997-11-01

    Cortical depolarization was investigated in a topographic gradient of ischemic density after 1-hour transient middle cerebral artery occlusion in halothane-anesthetized cats. A laser Doppler flow probe, an ion-selective microelectrode, and a nitric oxide (NO) electrode measured regional CBF (rCBF), direct current (DC) potential, extracellular Ca2+ concentration ([Ca2+]o), and NO concentration in ectosylvian and suprasylvian gyri of nine animals. Recordings revealed 12 of 18 sites with persistent negative shifts of the DC potential, severe rCBF reduction, and a drop of [Ca2+]o characteristic for core regions of focal ischemia. Among these sites, two types were distinguished by further analysis. In Type 1 (n = 5), rapid, negative DC shifts resembled anoxic depolarization as described for complete global ischemia. In this type, ischemia was most severe (8.9 +/- 2.5% of control rCBF), [Ca2+]o dropped fast and deepest (0.48 +/- 0.20 mmol/L), and NO concentration increased transiently (36.1 +/- 24.0 nmol/L at 2.5 minutes), and decreased thereafter. In Type 2 (n = 7), the DC potential fell gradually over the first half of the ischemic episode, rCBF and [Ca2+]o reductions were smaller than in Type 1 (16.2 +/- 8.2%; 0.77 +/- 0.41 mmol/L), and NO increased continuously during ischemia (53.1 +/- 60.4 nmol/L at 60 minutes) suggesting that in this type NO most likely exerts its diverse actions on ischemia-threatened tissue. In the remaining six recording sites, a third type (Type 3) attributable to the ischemic periphery was characterized by minimal DC shifts, mild ischemia (37.2 +/- 13.3%), nonsignificant alterations of [Ca2+]o, but decreased NO concentrations during middle cerebral artery occlusion. Reperfusion returned the various parameters to baseline levels within 1 hour, the recovery of [Ca2+]o and NO concentration being delayed in Type 1. An NO synthase inhibitor (N(G)-nitro-L-arginine, 50 mg/kg intravenously; four animals) abolished NO elevation during ischemia. In

  18. Ion beam stabilization in ion implantation equipment

    International Nuclear Information System (INIS)

    Pina, L.

    1973-01-01

    The results are presented of experimental efforts aimed at ion beam current stabilization in an equipment for ion implantation in solids. The related problems of power supplies are discussed. Measured characteristics of laboratory equipment served the determination of the parameters to be required of the supplies as well as the design and the construction of the supplies. The respective wiring diagram is presented. (J.K.)

  19. Risk of osteoporosis in first degree relatives of patients with diabetes mellitus: a study of bone mineral ions

    International Nuclear Information System (INIS)

    Rana, G.E.; Malik, A.; Khurshid, R.

    2011-01-01

    Diabetes may influence the bone in multiple pathways, some with contradictory effects. These mechanisms include changes in insulin and hypercalciuria, phophatemia, hypomagnesaemia associated with glycosuria. We tried to find out level of minerals in first degree relatives of patients with diabetes mellitus as there is relationship between bone minerals and glycemic controls. Methods: Fifty local subjects age range 40 -50 years with family history of diabetes (first degree relatives) were included in the study. Duration of study was 6 months. Levels of blood sugar, serum calcium, phosphorus and magnesium were estimated by standard Randox kits. 10 males and 10 female subjects with no history of diabetes were considered as normal controls. Results: The level of blood glucose in both sexes was increased as compared to their controls but this showed no significant difference. Level of serum calcium and magnesium were significantly decreased (p<0.05, 0.001) in both males and females when compared with the values of their controls. Level of phosphorous was significantly increased ( p<0.05) in both first degree relatives of ma le and females as compared to level of phosphorous of their controls. Conclusion: Pre-diabetes and undiagnosed T2DM are conditions for which screening can be helpful to find out that first degree relatives not only at risk to develop diabetes but they also likely to develop osteoporosis in a sizable portion of the population. However there is a need for further research including the incidence and risk factors for osteoporotic fractures in first degree relatives of diabetics. (author)

  20. The Possible Role of Smoking and Mild Inflammation on Iron, Copper Ions and Related Metalloproteins in Male Volunteers Working in Radiation Field

    International Nuclear Information System (INIS)

    Bahgat, M.M.; Amer, M.M.; Michael, M.I.; El Daly, E.S.

    2009-01-01

    Oxidative stress implies that cells have intact pro-oxidant/anti-oxidant systems that continuously generate and detoxify oxidants during normal aerobic metabolism. When additional oxidative events occur, the pro-oxidant systems out balance the anti-oxidant, potentially producing oxidative damage to lipids, proteins, carbohydrates, and nucleic acids ultimately leading to cell death in severe oxidative stress. A disturbance in pro-oxidant/anti-oxidant systems results from a myriad of different oxidative challenges, including radiation, metabolism of environmental pollutants and administered drugs and immune system response to disease or infection. Forty male volunteers have participated in this study to evaluate the effect of smoking and mild infection on ferric and copper ions, related metalloproteins and glutathione peroxidase in males working in the radiation fields. The results denoted that those two stress ors added further imbalance in the pro oxidant-antioxidant status

  1. Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities

    Energy Technology Data Exchange (ETDEWEB)

    Mark, J.W.K.

    1982-03-22

    Calculations suggest that experiments relating to disk heating, as well as beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the low beam emittance of suggested multi-beam designs are very useful. Possibly even higher focal spot brightness could be obtained by plasma lenses which involve external fields on the beam which is stripped to a higher charge state by passing through a plasma cell. Preliminary results suggest that intensities approx. 10/sup 13/ - 10/sup 14/ W/cm/sup 2/ are achievable. Given these intensities, deposition experiments with heating of disks to greater than a million degrees Kelvin (100 eV) are expected.

  2. Aliphatic long chain quaternary ammonium compounds analysis by ion-pair chromatography coupled with suppressed conductivity and UV detection in lysing reagents for blood cell analysers.

    Science.gov (United States)

    Giovannelli, D; Abballe, F

    2005-08-26

    A method has been developed which allows simultaneous determination of three linear alkyl trimethylammonium salts. Dodecyltrimethylammonium chloride, tetradecyltrimethylammonium bromide and hexadecyltrimethylammonium chloride are widely used as main active ingredients of lysing reagents for blood cell analyzers which perform white blood cells differential determination into two or more sub-populations by impedance analysis. The ion-pair on styrene-divinyl benzene chromatographic phase looks like a suitable, reliable and long term stable tool for separation of such quaternary compounds. The detection based on suppressed conductivity was chosen because of the lack of significance chromophores. A micromembrane suppressor device compatible with high solvent concentration (up to 80%) was used in order to minimize the conductivity background before the detection. In the present work we show how the chemical post column derivatization makes the alkyl chain detectable also by UV direct detection at 210 nm.

  3. Ion Colliders

    CERN Document Server

    Fischer, W

    2014-01-01

    High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

  4. Recoil ions

    International Nuclear Information System (INIS)

    Cocke, C.L.; Olson, R.E.

    1991-01-01

    The collision of a fast moving heavy ion with a neutral atomic target can produce very highly charged but slowly moving target ions. This article reviews experimental and theoretical work on the production and use of recoil ions beyond the second ionization state by beams with specific energies above 0.5 MeV/amu. A brief historical survey is followed by a discussion of theoretical approaches to the problem of the removal of many electrons from a neutral target by a rapid, multiply charged projectile. A discussion of experimental techniques and results for total and differential cross sections for multiple ionization of atomic and molecular targets is given. Measurements of recoil energy are discussed. The uses of recoil ions for in situ spectroscopy of multiply charged ions, for external beams of slow, highly charged ions and in ion traps are reviewed. Some possible future opportunities are discussed. (orig.)

  5. Evaluation of the relative thermoluminescence efficiency of LiF:Mg,Ti and LiF:Mg,Cu,P TL detectors to low-energy heavy ions

    DEFF Research Database (Denmark)

    Gieszczyk, W.; Bilski, P.; Olko, P.

    2013-01-01

    and xenon ion beams, at energies ranging from 5.0 to 9.3 MeV/n. Supra- and sublinear response was found, for the MTS-N and MCP-N, respectively, similarly as observed for γ-rays. However, the level of nonlinearity of response of studied detectors is strongly reduced by increasing values of the ion ionization...... density (no supralinearity for Xe ions, for MTS-N, within calculated uncertainties). The growth of high-temperature TL peaks, with increasing ionization density, was observed for MCP-N, what was not previously reported. At the whole range of applied energies higher efficiencies were noted for MTS......-N, for all ion species. A decrease of the efficiency with decrease of the ion energy was confirmed, for both types of studied detectors. At a given energy, higher efficiency was observed for lighter ions, because of the lower ionization density. Significantly higher decrease of the efficiency was measured...

  6. Ni(ii) ions cleave and inactivate human alpha-1 antitrypsin hydrolytically, implicating nickel exposure as a contributing factor in pathologies related to antitrypsin deficiency.

    Science.gov (United States)

    Wezynfeld, Nina Ewa; Bonna, Arkadiusz; Bal, Wojciech; Frączyk, Tomasz

    2015-04-01

    Human alpha-1 antitrypsin (AAT) is an abundant serum protein present at a concentration of 1.0-1.5 g L(-1). AAT deficiency is a genetic disease that manifests with emphysema and liver cirrhosis due to the accumulation of a misfolded AAT mutant in hepatocytes. Lung AAT amount is inversely correlated with chronic obstructive pulmonary disease (COPD), a serious and often deadly condition, with increasing frequency in the aging population. Exposure to cigarette smoke and products of fossil fuel combustion aggravates AAT deficiency and COPD according to mechanisms that are not fully understood. Taking into account that these fumes contain particles that can release nickel to human airways and skin, we decided to investigate interactions of AAT with Ni(ii) ions within the paradigm of Ni(ii)-dependent peptide bond hydrolysis. We studied AAT protein derived from human blood using HPLC, SDS-PAGE, and mass spectrometry. These studies were aided by spectroscopic experiments on model peptides. As a result, we identified three hydrolysis sites in AAT. Two of them are present in the N-terminal part of the molecule next to each other (before Thr-13 and Ser-14 residues) and effectively form one N-terminal cleavage site. The single C-terminal cleavage site is located before Ser-285. The N-terminal hydrolysis was more efficient than the C-terminal one, but both abolished the ability of AAT to inhibit trypsin in an additive manner. Nickel ions bound to hydrolysis products demonstrated an ability to generate ROS. These results implicate Ni(ii) exposure as a contributing factor in AAT-related pathologies.

  7. Ion Implantation of Polymers

    DEFF Research Database (Denmark)

    Popok, Vladimir

    2012-01-01

    The current paper presents a state-of-the-art review in the field of ion implantation of polymers. Numerous published studies of polymers modified by ion beams are analysed. General aspects of ion stopping, latent track formation and changes of structure and composition of organic materials...... are discussed. Related to that, the effects of radiothermolysis, degassing and carbonisation are considered. Specificity of depth distributions of implanted into polymers impurities is analysed and the case of high-fluence implantation is emphasised. Within rather broad topic of ion bombardment, the focus...... is put on the low-energy implantation of metal ions causing the nucleation and growth of nanoparticles in the shallow polymer layers. Electrical, optical and magnetic properties of metal/polymer composites are under the discussion and the approaches towards practical applications are overviewed....

  8. High current ion sources

    International Nuclear Information System (INIS)

    Brown, I.G.

    1989-06-01

    The concept of high current ion source is both relative and evolutionary. Within the domain of one particular kind of ion source technology a current of microamperers might be 'high', while in another area a current of 10 Amperes could 'low'. Even within the domain of a single ion source type, what is considered high current performance today is routinely eclipsed by better performance and higher current output within a short period of time. Within their fields of application, there is a large number of kinds of ion sources that can justifiably be called high current. Thus, as a very limited example only, PIGs, Freemen sources, ECR sources, duoplasmatrons, field emission sources, and a great many more all have their high current variants. High current ion beams of gaseous and metallic species can be generated in a number of different ways. Ion sources of the kind developed at various laboratories around the world for the production of intense neutral beams for controlled fusion experiments are used to form large area proton deuteron beams of may tens of Amperes, and this technology can be used for other applications also. There has been significant progress in recent years in the use of microwave ion sources for high current ion beam generation, and this method is likely to find wide application in various different field application. Finally, high current beams of metal ions can be produced using metal vapor vacuum arc ion source technology. After a brief consideration of high current ion source design concepts, these three particular methods are reviewed in this paper

  9. Plasma-surface interaction at sharp edges and corners during ion-assisted physical vapor deposition. Part I: Edge-related effects and their influence on coating morphology and composition

    International Nuclear Information System (INIS)

    Macak, E.B.; Muenz, W.-D.; Rodenburg, J.M.

    2003-01-01

    Ion-assisted physical vapor deposition (PVD) is a common industrial method for growing thin coatings of various interstitial nitride alloys. The interaction between the ions and three-dimensional nonflat samples during the deposition can, however, lead to unwanted local changes in the properties of the coating and thus its performance. We analyze the characteristics of the ion bombardment during ion-assisted PVD on sharp convex substrates and their effect on the growing coating. We show that the magnitude and the spatial extent of the edge-related changes are directly related to the characteristics of the plasma sheath around the biased edges. We examine the influence of the edge geometry and the deposition conditions. The edge-related effects are studied on the example of wedge-shaped samples coated with TiAlN/VN by closed-field unbalanced magnetron deposition process using high-flux low-energy Ar + -ion irradiation (J i /J me ∼4, E i =75-150 eV). The samples are analyzed by scanning electron microscopy and energy-dispersive x-ray spectroscopy. Significant changes in the morphology, thickness, and composition of the coatings are found in the edge region. In order to account for the changes, we apply a self-consistent model of the plasma sheath around wedge-shaped samples proposed by Watterson [J. Phys. D 22, 1300 (1989)], to our conditions. For a 30 deg. wedge coated at -150 V, the resputtering rate in the edge region is found to be increased by up to ten times as compared to flat substrate areas. The effect is due to the combined action of an increased ion flux and increased sputtering yield as a result of the nonperpendicular angle of incidence of ions in the edge region. The situation at sharp corners, where even more severe effects are observed, is analyzed and modeled in the companion article E. B. Macak et al., J. Appl. Phys. (2003) (Part II)

  10. Ion colliders

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions (77Asb1, 81Bou1). The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  11. Ion colliders

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.

    2011-12-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  12. Effects of inorganic ions on morphology of octacalcium phosphate grown on cation selective membrane at physiological temperature and pH in relation to enamel formation

    Science.gov (United States)

    Iijima, Mayumi; Moriwaki, Yutaka

    1989-05-01

    The crystal growth of octacalcium phosphate (OCP) is of particular interest, since there is a possibility that OCP is formed in the early stage of tooth enamel formation. In this study, the effects of CO2-3, Mg2+ and F-ions on the morphology of OCP were investigated in a membrane system, where a cation selective membrane was used to simulate amelogenesis. Reactions were carried out at pH 6.3, 6.5 and 6.8 for 3 days at 37°C. In most cases, these ions suppressed the crystal growth in the c-axis direction of OCP, particularly when they coexisted. The morphology of OCP crystal changed from ribbon-like to flake-like, depending on the inhibitory activity. The inhibitory activity, particularly that of F - ion, was suppressed at pH lower than pH 6.8. Antagonistic effect of Mg2+ and F-ion was observed at pH 6.5. In the case of F - ion, OCP crystals showed a unique pattern, which suggests hydrolysis of OCP and subsequent growth of apatite. These findings indicate that inorganic ions, particularly F - ion, influence the growth of OCP. Although CO2-3, Mg2+andF-ions coexisted, extended growth in the c-axis direction of OCP took place at pH 6.0.

  13. Temporal Lobe Reactions After Carbon Ion Radiation Therapy: Comparison of Relative Biological Effectiveness–Weighted Tolerance Doses Predicted by Local Effect Models I and IV

    Energy Technology Data Exchange (ETDEWEB)

    Gillmann, Clarissa, E-mail: clarissa.gillmann@med.uni-heidelberg.de [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Jäkel, Oliver [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Heidelberg Ion Beam Therapy Center (HIT), Heidelberg (Germany); Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany); Schlampp, Ingmar [Department of Radiation Oncology and Radiation Therapy, Heidelberg University Hospital, Heidelberg (Germany); Karger, Christian P. [Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2014-04-01

    Purpose: To compare the relative biological effectiveness (RBE)–weighted tolerance doses for temporal lobe reactions after carbon ion radiation therapy using 2 different versions of the local effect model (LEM I vs LEM IV) for the same patient collective under identical conditions. Methods and Materials: In a previous study, 59 patients were investigated, of whom 10 experienced temporal lobe reactions (TLR) after carbon ion radiation therapy for low-grade skull-base chordoma and chondrosarcoma at Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt, Germany in 2002 and 2003. TLR were detected as visible contrast enhancements on T1-weighted MRI images within a median follow-up time of 2.5 years. Although the derived RBE-weighted temporal lobe doses were based on the clinically applied LEM I, we have now recalculated the RBE-weighted dose distributions using LEM IV and derived dose-response curves with Dmax,V-1 cm³ (the RBE-weighted maximum dose in the remaining temporal lobe volume, excluding the volume of 1 cm³ with the highest dose) as an independent dosimetric variable. The resulting RBE-weighted tolerance doses were compared with those of the previous study to assess the clinical impact of LEM IV relative to LEM I. Results: The dose-response curve of LEM IV is shifted toward higher values compared to that of LEM I. The RBE-weighted tolerance dose for a 5% complication probability (TD{sub 5}) increases from 68.8 ± 3.3 to 78.3 ± 4.3 Gy (RBE) for LEM IV as compared to LEM I. Conclusions: LEM IV predicts a clinically significant increase of the RBE-weighted tolerance doses for the temporal lobe as compared to the currently applied LEM I. The limited available photon data do not allow a final conclusion as to whether RBE predictions of LEM I or LEM IV better fit better clinical experience in photon therapy. The decision about a future clinical application of LEM IV therefore requires additional analysis of temporal lobe reactions in a

  14. Ion temperature via laser scattering on ion Bernstein waves

    International Nuclear Information System (INIS)

    Wurden, G.A.; Ono, M.; Wong, K.L.

    1981-10-01

    Hydrogen ion temperature has been measured in a warm toroidal plasma with externally launched ion Bernstein waves detected by heterodyne CO 2 laser scattering. Radial scanning of the laser beam allows precise determination of k/sub perpendicular to/ for the finite ion Larmor radius wave (ω approx. less than or equal to 2Ω/sub i/). Knowledge of the magnetic field strength and ion concentration then give a radially resolved ion temperature from the dispersion relation. Probe measurements and Doppler broadening of ArII 4806A give excellent agreement

  15. Transformation of alpha-tocopherol (vitamin E) and related chromanol model compounds into their phenoxonium ions by chemical oxidation with the nitrosonium cation.

    Science.gov (United States)

    Lee, Stephen B; Lin, Ching Yeh; Gill, Peter M W; Webster, Richard D

    2005-12-09

    [reaction: see text] Alpha-tocopherol (alpha-TOH), the main oil component making up vitamin E, and its nonnatural solid 6-hydroxy-2,2,5,7,8-pentamethylchroman and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid structurally related analogues were oxidized quantitatively with 2 mol equiv of NO+ SbF6(-) in CH3CN at 233 K to form phenoxonium cations (alpha-TO+ SbF6(-)) in a chemically reversible two-electron/one-proton process. Solution-phase infrared spectroscopy, 1H and 13C NMR spectroscopy, and corresponding theoretical calculations of the spectroscopic data using density-based and wave-function-based models support the identity of the remarkably stable phenoxonium cations. The presence of an oxygen atom in the para position to the hydroxyl group and the chromanol ring structure appear to be important factors in stabilization of the phenoxonium ions, which raises the interesting possibility that the cations play a crucial role in the mode of action of vitamin E in biological systems. Although the phenoxonium cations are reactive toward nucleophiles such as water, they may be moderately stable in the hydrophobic (lipophilic) environment where vitamin E is known to occur naturally.

  16. Confirmatory analysis method for zeranol, its metabolites and related mycotoxins in urine by liquid chromatography-negative ion electrospray tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bennekom, E.O. van; Brouwer, L.; Laurant, E.H.M.; Hooijerink, H.; Nielen, M.W.F

    2002-11-25

    The determination of the banned anabolic substance zeranol and the metabolites taleranol and zearalanone in bovine urine is complicated by the occurrence of the structurally-related mycotoxin zearalenone and the corresponding {alpha}- and {beta}-zearalenol metabolites which possess similar estrogenic properties. A liquid chromatography-negative ion electrospray tandem mass spectrometric method is presented for the confirmatory analysis of all six resorcylic acid lactones ('zeranols') in urine samples using deuterium-labelled internal standards. The method was validated as a confirmatory method for bovine urine samples according to new draft EU guidelines and showed good precision and linearity, and CC{alpha} and CC{beta} values of 0.02-0.30 and <1.0 ng ml{sup -1}, respectively. The applicability was demonstrated by comparing the results of an incurred sample with previous results on the same sample obtained by gas chromatography high resolution mass spectrometry. Preliminary data show that following a simple matrix solid phase dispersion clean-up, liver samples from poultry will be amenable to this method as well.

  17. Confirmatory analysis method for zeranol, its metabolites and related mycotoxins in urine by liquid chromatography-negative ion electrospray tandem mass spectrometry

    International Nuclear Information System (INIS)

    Bennekom, E.O. van; Brouwer, L.; Laurant, E.H.M.; Hooijerink, H.; Nielen, M.W.F.

    2002-01-01

    The determination of the banned anabolic substance zeranol and the metabolites taleranol and zearalanone in bovine urine is complicated by the occurrence of the structurally-related mycotoxin zearalenone and the corresponding α- and β-zearalenol metabolites which possess similar estrogenic properties. A liquid chromatography-negative ion electrospray tandem mass spectrometric method is presented for the confirmatory analysis of all six resorcylic acid lactones ('zeranols') in urine samples using deuterium-labelled internal standards. The method was validated as a confirmatory method for bovine urine samples according to new draft EU guidelines and showed good precision and linearity, and CCα and CCβ values of 0.02-0.30 and -1 , respectively. The applicability was demonstrated by comparing the results of an incurred sample with previous results on the same sample obtained by gas chromatography high resolution mass spectrometry. Preliminary data show that following a simple matrix solid phase dispersion clean-up, liver samples from poultry will be amenable to this method as well

  18. Experimental Evaluation of a Negative Ion Source for a Heavy Ion Fusion Negative Ion Driver

    International Nuclear Information System (INIS)

    Grisham, L.R.; Hahto, S.K.; Hahto, S.T.; Kwan, J.W.; Leung, K.N.

    2004-01-01

    Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photo-detached to neutrals. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm 2 was obtained under the same conditions that gave 57 45 mA/cm 2 of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that i s used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl - was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 45 mA/cm 2 , sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source

  19. ion irradiation

    Indian Academy of Sciences (India)

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in ...

  20. Ion microprobes

    International Nuclear Information System (INIS)

    Coles, J.N.; Long, J.V.P.

    1977-01-01

    An ion microprobe is described that has an ion extraction arrangement comprising two separate paths for ions and electrons diverging from a common point. A cone shaped or pyramidal guard electrode surrounds each path the apex angles being equal and coinciding with the said point. The guard electrodes are positioned to lie tangentially to each other and to a planar surface including the said point. An aperture is provided for the two paths at the apexes of both guard electrodes, and electrical connections between the guard electrodes enable the same potential to be applied to both guard electrodes. Means are provided for generating oppositely polarised electric fields within the guard electrodes, together with means for causing a focused ion beam to strike the common point without suffering astigmatism. The means for causing a focused ion beam to strike the said point includes an ion gun for directing an ion beam along one of the paths and means to provide an axial accelerating field there along. Optical viewing means are also provided. Existing designs enable only ions or electrons, but not both, to be extracted at any one time. (U.K.)

  1. Characterization of a multilayer ionization chamber prototype for fast verification of relative depth ionization curves and spread-out-Bragg-peaks in light ion beam therapy.

    Science.gov (United States)

    Mirandola, Alfredo; Magro, Giuseppe; Lavagno, Marco; Mairani, Andrea; Molinelli, Silvia; Russo, Stefania; Mastella, Edoardo; Vai, Alessandro; Maestri, Davide; La Rosa, Vanessa; Ciocca, Mario

    2018-05-01

    To dosimetrically characterize a multilayer ionization chamber (MLIC) prototype for quality assurance (QA) of pristine integral ionization curves (ICs) and spread-out-Bragg-peaks (SOBPs) for scanning light ion beams. QUBE (De.Tec.Tor., Torino, Italy) is a modular detector designed for QA in particle therapy (PT). Its main module is a MLIC detector, able to evaluate particle beam relative depth ionization distributions at different beam energies and modulations. The charge collecting electrodes are made of aluminum, for a nominal water equivalent thickness (WET) of ~75 mm. The detector prototype was calibrated by acquiring the signals in the initial plateau region of a pristine BP and in terms of WET. Successively, it was characterized in terms of repeatability response, linearity, short-term stability and dose rate dependence. Beam-induced measurements of activation in terms of ambient dose equivalent rate were also performed. To increase the detector coarse native spatial resolution (~2.3 mm), several consecutive acquisitions with a set of certified 0.175-mm-thick PMMA sheets (Goodfellow, Cambridge Limited, UK), placed in front of the QUBE mylar entrance window, were performed. The ICs/SOBPs were achieved as the result of the sum of the set of measurements, made up of a one-by-one PMMA layer acquisition. The newly obtained detector spatial resolution allowed the experimental measurements to be properly comparable against the reference curves acquired in water with the PTW Peakfinder. Furthermore, QUBE detector was modeled in the FLUKA Monte Carlo (MC) code following the technical design details and ICs/SOBPs were calculated. Measurements showed a high repeatability: mean relative standard deviation within ±0.5% for all channels and both particle types. Moreover, the detector response was linear with dose (R 2  > 0.998) and independent on the dose rate. The mean deviation over the channel-by-channel readout respect to the reference beam flux (100%) was equal

  2. A Study of Moroccan Pupils' Difficulties at Second Baccalaureate Year in Solving Chemistry Problems Relating to the Reactivity of Ethanoate Ions and to Copper-Aluminium Cells

    Science.gov (United States)

    Ouasri, Ali

    2017-01-01

    This paper investigates the difficulties that Moroccan pupils (18-19) of the second Baccalaureate year encountered in solving chemical equilibrium problems relating to ethanoate ions' reactivity with water and methanoic acid, and to copper-aluminum cells. The pupils were asked to provide answers to questions derived from two problems. The…

  3. CoCr wear particles generated from CoCr alloy metal-on-metal hip replacements, and cobalt ions stimulate apoptosis and expression of general toxicology-related genes in monocyte-like U937 cells

    Energy Technology Data Exchange (ETDEWEB)

    Posada, Olga M., E-mail: O.M.PosadaEstefan@leeds.ac.uk [Biomedical Engineering Department, University of Strathclyde, Wolfson Centre, Glasgow G4 0NW (United Kingdom); Gilmour, Denise [Pure and Applied Chemistry Department, University of Strathclyde, Thomas Graham Building, Glasgow G1 1XL (United Kingdom); Tate, Rothwelle J., E-mail: r.j.tate@strath.ac.uk [Strathclyde Institute for Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE (United Kingdom); Grant, M. Helen [Biomedical Engineering Department, University of Strathclyde, Wolfson Centre, Glasgow G4 0NW (United Kingdom)

    2014-11-15

    Cobalt-chromium (CoCr) particles in the nanometre size range and their concomitant release of Co and Cr ions into the patients' circulation are produced by wear at the articulating surfaces of metal-on-metal (MoM) implants. This process is associated with inflammation, bone loss and implant loosening and led to the withdrawal from the market of the DePuy ASR™ MoM hip replacements in 2010. Ions released from CoCr particles derived from a resurfacing implant in vitro and their subsequent cellular up-take were measured by ICP-MS. Moreover, the ability of such metal debris and Co ions to induce both apoptosis was evaluated with both FACS and immunoblotting. qRT-PCR was used to assess the effects on the expression of lymphotoxin alpha (LTA), BCL2-associated athanogene (BAG1), nitric oxide synthase 2 inducible (NOS2), FBJ murine osteosarcoma viral oncogene homolog (FOS), growth arrest and DNA-damage-inducible alpha (GADD45A). ICP-MS showed that the wear debris released significant (p < 0.05) amounts of Co and Cr ions into the culture medium, and significant (p < 0.05) cellular uptake of both ions. There was also an increase (p < 0.05) in apoptosis after a 48 h exposure to wear debris. Analysis of qRT-PCR results found significant up-regulation (p < 0.05) particularly of NOS2 and BAG1 in Co pre-treated cells which were subsequently exposed to Co ions + debris. Metal debris was more effective as an inducer of apoptosis and gene expression when cells had been pre-treated with Co ions. This suggests that if a patient receives sequential bilateral CoCr implants, the second implant may be more likely to produce adverse effects than the first one. - Highlights: • Effects of CoCr nanoparticles and Co ions on U937 cells were investigated. • Ions released from wear debris play an important role in cellular response, • Toxicity of Co ions could be related to NO metabolic processes and apoptosis. • CoCr particles were a more effective inducer of apoptosis after cell

  4. Spatial distribution of ion energy related on electron density in a plasma channel generated in gas clusters by a femtosecond laser

    International Nuclear Information System (INIS)

    Nam, S. M.; Han, J. M.; Cha, Y. H.; Lee, Y. W.; Rhee, Y. J.; Cha, H. K.

    2008-01-01

    Neutron generation through Coulomb explosion of deuterium contained gas clusters is known as one of the very effective methods to produce fusion neutrons using a table top terawatt laser. The energy of ions produced through Coulomb explosions is very important factor to generate neutrons efficiently. Until the ion energy reaches around∼MeV level, the D D fusion reaction probability increases exponentially. The understanding of laser beam propagation and laser energy deposition in clusters is very important to improve neutron yields. As the laser beam propagates through clusters medium, laser energy is absorbed in clusters by ionization of molecules consisting clusters. When the backing pressure of gas increases, the average size of clusters increases and which results in higher energy absorption and earlier termination of laser propagation. We first installed a Michelson interferometer to view laser beam traces in a cluster plume and to measure spatial electron density profiles of a plasma channel which was produced by a laser beam. And then we measured the energy of ions distributed along the plasma channel with a translating slit to select ions from narrow parts of a plasma channel. In our experiments, methane gas was used to produce gas clusters at a room temperature and the energy distribution of proton ions for different gas backing pressure were measured by the time of flight method using dual micro channel plates. By comparing the distribution of ion energies and electron densities, we could understand the condition for effective laser energy delivery to clusters

  5. Ion implantation

    International Nuclear Information System (INIS)

    Johnson, E.

    1986-01-01

    It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

  6. Ion implantation control system

    International Nuclear Information System (INIS)

    Gault, R. B.; Keutzer, L. L.

    1985-01-01

    A control system is disclosed for an ion implantation system of the type in which the wafers to be implanted are mounted around the periphery of a disk which rotates and also moves in a radial direction relative to an ion beam to expose successive sections of each wafer to the radiation. The control system senses beam current which passes through one or more apertures in the disk and is collected by a Faraday cup. This current is integrated to obtain a measure of charge which is compared with a calculated value based upon the desired ion dosage and other parameters. The resultant controls the number of incremental steps the rotating disk moves radially to expose the adjacent sections of each wafer. This process is continued usually with two or more traverses until the entire surface of each wafer has been implanted with the proper ion dosage

  7. Ion implantation apparatus

    International Nuclear Information System (INIS)

    Forneris, J.L.; Hicks, W.W.; Keller, J.H.; McKenna, C.M.; Siermarco, J.A.; Mueller, W.F.

    1981-01-01

    The invention relates to ion bombardment or implantation apparatus. It comprises an apparatus for bombarding a target with a beam of ions, including an arrangement for measuring the ion beam current and controlling the surface potential of the target. This comprises a Faraday cage formed, at least in part, by the target and by walls adjacent to, and electrically insulated from, the target and surrounding the beam. There is at least one electron source for supplying electrons to the interior of the Faraday cage and means within the cage for blocking direct rectilinear radiation from the source to the target. The target current is measured and combined with the wall currents to provide a measurement of the ion beam current. The quantity of electrons supplied to the interior of the cage can be varied to control the target current and thereby the target surface potential. (U.K.)

  8. Electrostatic ion acoustic waves

    International Nuclear Information System (INIS)

    Hasegawa, A.

    1983-01-01

    In this paper, certain aspects of plasma physics are illustrated through a study of electrostatic ion acoustic waves. The paper consists of three Sections. Section II deals with linear properties of the ion acoustic wave including derivation of the dispersions relation with the effect of Landau damping and of an ambient magnetic field. The section also introduces the excitation processes of the ion acoustic wave due to an electron drift or to a stimulated Brillouin scattering. The nonlinear properties are introduced in Section III and IV. In Section III, incoherent nonlinear effects such as quasilinear and mode-coupling saturations of the instability are discussed. The coherent nonlinear effects such as the generation of ion acoustic solitons, shocks and weak double layers are presented in Section IV. (Auth.)

  9. Ion plasma electron gun

    International Nuclear Information System (INIS)

    Wakalopulos, G.

    1976-01-01

    In the disclosed electron gun positive ions generated by a hollow cathode plasma discharge in a first chamber are accelerated through control and shield grids into a second chamber containing a high voltage cold cathode. These positive ions bombard a surface of the cathode causing the cathode to emit secondary electrons which form an electron beam having a distribution adjacent to the cathode emissive surface substantially the same as the distribution of the ion beam impinging upon the cathode. After passing through the grids and the plasma discharge chamber, the electron beam exits from the electron gun via a foil window. Control of the generated electron beam is achieved by applying a relatively low control voltage between the control grid and the electron gun housing (which resides at ground potential) to control the density of the positive ions bombarding the cathode

  10. Localisation of SCN10A gene product Na(v)1.8 and novel pain-related ion channels in human heart.

    Science.gov (United States)

    Facer, Paul; Punjabi, Prakash P; Abrari, Andleeb; Kaba, Riyaz A; Severs, Nicholas J; Chambers, John; Kooner, Jaspal S; Anand, Praveen

    2011-01-01

    We have shown that the gene SCN10A encoding the sodium channel Na(v)1.8 is a susceptibility factor for heart block and serious ventricular arrhythmia. Since Na(v)1.8 is known to be present in nerve fibres that mediate pain, it may be related to both cardiac pain and dysrhythmia. The localisation of Na(v)1.8 and other key nociceptive ion channels, including Na(v)1.7, Na(v)1.9, capsaicin receptor TRPV1, and purinergic receptor P2X(3), have not been reported in human heart. The aim of this study was to determine the distribution of Na(v)1.8, related sodium and other sensory channels in human cardiac tissue, and correlate their density with sympathetic nerves, regenerating nerves (GAP-43), and vascularity. Human heart atrial appendage tissues (n = 13) were collected during surgery for valve disease. Tissues were investigated by immunohistology using specific antibodies to Na(v)1.8 and other markers. Na(v)1.8 immunoreactivity was detected in nerve fibres and fascicles in the myocardium, often closely associated with small capillaries. Na(v)1.8 nerve fibres per mm(2) correlated significantly with vascular markers. Na(v)1.8-immunoreactivity was present also in cardiomyocytes with a similar distribution pattern to that seen with connexins, the specialised gap junction proteins of myocardial intercalated discs. Na(v)1.5-immunoreactivity was detected in cardiomyocytes but not in nerve fibres. Na(v)1.7, Na(v)1.9, TRPV1, P2X(3)/P2X(2), and GAP43 positive nerve fibres were relatively sparse, whereas sympathetic innervation and connexin43 were abundant. We conclude that sodium channel Na(v)1.8 is present in sensory nerves and cardiomyocytes of human heart. Na(v)1.8 and other pain channels provide new targets for the understanding and treatment of cardiac pain and dysrhythmia.

  11. The potential of at-home prediction of the formation of urolithiasis by simple multi-frequency electrical conductivity of the urine and the comparison of its performance with urine ion-related indices, color and specific gravity.

    Science.gov (United States)

    Silverio, Angelito A; Chung, Wen-Yaw; Cheng, Cheanyeh; Wang, Hai-Lung; Kung, Chien-Min; Chen, Jun; Tsai, Vincent F S

    2016-04-01

    It is important to control daily diet, water intake and life style as well as monitor the quality of urine for urolithiasis prevention. For decades, many ion-related indices have been developed for predicting the formation of urinary stones or urolithiasis, such as EQUILs, relative supersaturation (RSS), Tiselius indices (TI), Robertson risk factor algorithms (RRFA) and more recently, the Bonn risk index. However, they mostly demand robust laboratory analysis, are work-intensive, and even require complex computational programs to get the concentration patterns of several urine analytes. A simple and fast platform for measuring multi-frequency electrical conductivity (MFEC) of morning spot urine (random urine) to predict the onset of urolithiasis was implemented in this study. The performance thereof was compared to ion-related indices, urine color and specific gravity. The concentrations of relevant ions, color, specific gravity (SG) and MFEC (MFEC tested at 1, 10, 100, 5001 KHz and 1 MHz) of 80 random urine samples were examined after collection. Then, the urine samples were stored at 4 °C for 24 h to determine whether sedimentation would occur or not. Ion-activity product index of calcium oxalate (AP(CaOx) EQ2) was calculated. The correlation between AP(CaOx) EQ2, urine color, SG and MFEC were analyzed. AP(CaOx) EQ2, urine color and MFEC (at 5 frequencies) all demonstrated good prediction (p = 0.01, 0.01, 0.01, respectively) for stone formation. The positive correlation between AP(CaOx) EQ2 and MFEC is also significant (p = 0.01). MFEC provides a good metric for predicting the onset of urolithiasis, which is comparable to conventional ion-related indices and urine color. This technology can be implemented with much ease for objectively monitoring the quality of urine at points-of-care or at home.

  12. High current vacuum arc ion source for heavy ion fusion

    International Nuclear Information System (INIS)

    Qi, N.; Schein, J.; Gensler, S.; Prasad, R.R.; Krishnan, M.; Brown, I.

    1999-01-01

    Heavy Ion fusion (HIF) is one of the approaches for the controlled thermonuclear power production. A source of heavy ions with charge states 1+ to 2+, in ∼0.5 A current beams with ∼20 micros pulse widths and ∼10 Hz repetition rates are required. Thermionic sources have been the workhorse for the HIF program to date, but suffer from sloe turn-on, heating problems for large areas, are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states, in short and long pulse bursts, with low emittance and high beam currents. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications is investigated. An existing ion source at LBNL was modified to produce ∼0.5 A, ∼60 keV Gd (A∼158) ion beams. The experimental effort concentrated on beam noise reduction, pulse-to-pulse reproducibility and achieving low beam emittance at 0.5 A ion current level. Details of the source development will be reported

  13. The physics and technology of ion sources

    International Nuclear Information System (INIS)

    Brown, I.G.

    1989-01-01

    New applications call for ion beams of unprecedented energy, current, species, focus, uniformity, size, and charge states. This comprehensive, up-to-date review and reference for the rapidly evolving field of ion source technology relates improvements to traditional ion sources and describes the development of the new kinds of ion sources. Also provides background material on the physics of ion sources. Chapters are self-contained, making for easy reference

  14. Relativity

    CERN Document Server

    Einstein, Albert

    2013-01-01

    Time magazine's ""Man of the Century"", Albert Einstein is the founder of modern physics and his theory of relativity is the most important scientific idea of the modern era. In this short book, Einstein explains, using the minimum of mathematical terms, the basic ideas and principles of the theory that has shaped the world we live in today. Unsurpassed by any subsequent books on relativity, this remains the most popular and useful exposition of Einstein's immense contribution to human knowledge.With a new foreword by Derek Raine.

  15. A laser activated ion source

    International Nuclear Information System (INIS)

    Hughes, J.; Luther-Davies, B.; Hora, H.; Kelly, J.

    1978-01-01

    Apparatus for generating energetic ions of a target material from a cold plasma of the material is described. A pulsed laser beam is directed onto the target to produce the cold plasma. Laser beam pulses are short in relation to the collision time in the plasma. Non-linear elctrodynamic forces within the plasma act to accelerate and eject ions from the plasma. The apparatus can be used to separate ions of isotopes of an element

  16. Gas and metal ion sources

    International Nuclear Information System (INIS)

    Oaks, E.; Yushkov, G.

    1996-01-01

    The positive ion sources are now of interest owing to both their conventional use, e.g., as injectors in charged-particle accelerators and the promising capabilities of intense ion beams in the processes related to the action of ions on various solid surfaces. For industrial use, the sources of intense ion beams and their power supplies should meet the specific requirements as follows: They should be simple, technologically effective, reliable, and relatively low-cost. Since the scanning of an intense ion beam is a complicated problem, broad ion beams hold the greatest promise. For the best use of such beams it is desirable that the ion current density be uniformly distributed over the beam cross section. The ion beam current density should be high enough for the treatment process be accomplished for an acceptable time. Thus, the ion sources used for high-current, high-dose metallurgical implantation should provide for gaining an exposure dose of ∼ 10 17 cm -2 in some tens of minutes. So the average ion current density at the surface under treatment should be over 10 -5 A/cm 2 . The upper limit of the current density depends on the admissible heating of the surface under treatment. The accelerating voltage of an ion source is dictated by its specific use; it seems to lie in the range from ∼1 kV (for the ion source used for surface sputtering) to ∼100 kV and over (for the ion sources used for high-current, high-dose metallurgical implantation)

  17. Planetary Ions at Mercury: Unanswered Questions After MESSENGER

    Science.gov (United States)

    Raines, J. M.

    2018-05-01

    We will discuss the key open questions relating to planetary ions, including the behavior of recently created photoions, the near absence of Ca+ / K+ in MESSENGER ion measurements, and the role of ion sputtering in the system.

  18. WE-H-BRA-01: BEST IN PHYSICS (THERAPY): Nano-Dosimetric Kinetic Model for Variable Relative Biological Effectiveness of Proton and Ion Beams

    Energy Technology Data Exchange (ETDEWEB)

    Abolfath, R; Bronk, L; Titt, U.; Grosshans, D; Mohan, R [The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Helo, Y [University College London, London (United Kingdom); Schuemann, J [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: Recent clonogenic cell survival and γH2AX studies suggest proton relative biological effectiveness (RBE) may be a non-linear function of linear energy transfer (LET) in the distal edge of the Bragg peak and beyond. We sought to develop a multiscale model to account for non-linear response phenomena to aid in the optimization of intensity-modulated proton therapy. Methods: The model is based on first-principle simulations of proton track structures, including secondary ions, and an analytical derivation of the dependence on particle LET of the linear-quadratic (LQ) model parameters α and β. The derived formulas are an extension of the microdosimetric kinetic (MK) model that captures dissipative track structures and non-Poissonian distribution of DNA damage at the distal edge of the Bragg peak and beyond. Monte Carlo simulations were performed to confirm the non-linear dose-response characteristics arising from the non-Poisson distribution of initial DNA damage. Results: In contrast to low LET segments of the proton depth dose, from the beam entrance to the Bragg peak, strong deviations from non-dissipative track structures and Poisson distribution in the ionization events in the Bragg peak distal edge govern the non-linear cell response and result in the transformation α=(1+c-1 L) α-x+2(c-0 L+c-2 L^2 )(1+c-1 L) β-x and β=(1+c-1 L)^2 β-x. Here L is the charged particle LET, and c-0,c-1, and c-2 are functions of microscopic parameters and can be served as fitting parameters to the cell-survival data. In the low LET limit c-1, and c-2 are negligible hence the linear model proposed and used by Wilkins-Oelfke for the proton treatment planning system can be retrieved. The present model fits well the recent clonogenic survival data measured recently in our group in MDACC. Conclusion: The present hybrid method provides higher accuracy in calculating the RBE-weighted dose in the target and normal tissues.

  19. WE-H-BRA-01: BEST IN PHYSICS (THERAPY): Nano-Dosimetric Kinetic Model for Variable Relative Biological Effectiveness of Proton and Ion Beams

    International Nuclear Information System (INIS)

    Abolfath, R; Bronk, L; Titt, U.; Grosshans, D; Mohan, R; Helo, Y; Schuemann, J

    2016-01-01

    Purpose: Recent clonogenic cell survival and γH2AX studies suggest proton relative biological effectiveness (RBE) may be a non-linear function of linear energy transfer (LET) in the distal edge of the Bragg peak and beyond. We sought to develop a multiscale model to account for non-linear response phenomena to aid in the optimization of intensity-modulated proton therapy. Methods: The model is based on first-principle simulations of proton track structures, including secondary ions, and an analytical derivation of the dependence on particle LET of the linear-quadratic (LQ) model parameters α and β. The derived formulas are an extension of the microdosimetric kinetic (MK) model that captures dissipative track structures and non-Poissonian distribution of DNA damage at the distal edge of the Bragg peak and beyond. Monte Carlo simulations were performed to confirm the non-linear dose-response characteristics arising from the non-Poisson distribution of initial DNA damage. Results: In contrast to low LET segments of the proton depth dose, from the beam entrance to the Bragg peak, strong deviations from non-dissipative track structures and Poisson distribution in the ionization events in the Bragg peak distal edge govern the non-linear cell response and result in the transformation α=(1+c_1 L) α_x+2(c_0 L+c_2 L^2 )(1+c_1 L) β_x and β=(1+c_1 L)^2 β_x. Here L is the charged particle LET, and c_0,c_1, and c_2 are functions of microscopic parameters and can be served as fitting parameters to the cell-survival data. In the low LET limit c_1, and c_2 are negligible hence the linear model proposed and used by Wilkins-Oelfke for the proton treatment planning system can be retrieved. The present model fits well the recent clonogenic survival data measured recently in our group in MDACC. Conclusion: The present hybrid method provides higher accuracy in calculating the RBE-weighted dose in the target and normal tissues.

  20. Tachykinin-Related Peptides Share a G Protein-Coupled Receptor with Ion Transport Peptide-Like in the Silkworm Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Chiaki Nagai-Okatani

    Full Text Available Recently, we identified an orphan Bombyx mori neuropeptide G protein-coupled receptor (BNGR-A24 as an ion transport peptide-like (ITPL receptor. BNGR-A24 belongs to the same clade as BNGR-A32 and -A33, which were recently identified as natalisin receptors. Since these three BNGRs share high similarities with known receptors for tachykinin-related peptides (TRPs, we examined whether these BNGRs can function as physiological receptors for five endogenous B. mori TRPs (TK-1-5. In a heterologous expression system, BNGR-A24 acted as a receptor for all five TRPs. In contrast, BNGR-A32 responded only to TK-5, and BNGR-A33 did not respond to any of the TRPs. These findings are consistent with recent studies on the ligand preferences for B. mori natalisins. Furthermore, we evaluated whether the binding of ITPL and TRPs to BNGR-A24 is competitive by using a Ca2+ imaging assay. Concomitant addition of a TRP receptor antagonist, spantide I, reduced the responses of BNGR-A24 not only to TK-4 but also to ITPL. The results of a binding assay using fluorescent-labeled BNGR-A24 and ligands demonstrated that the binding of ITPL to BNGR-A24 was inhibited by TK-4 as well as by spantide I, and vice versa. In addition, the ITPL-induced increase in cGMP levels of BNGR-A24-expressing BmN cells was suppressed by the addition of excess TK-4 or spantide I. The intracellular levels of cAMP and cGMP, as second messenger candidates of the TRP signaling, were not altered by the five TRPs, suggesting that these peptides act via different signaling pathways from cAMP and cGMP signaling at least in BmN cells. Taken together, the present findings suggest that ITPL and TRPs are endogenous orthosteric ligands of BNGR-A24 that may activate discrete signaling pathways. This receptor, which shares orthosteric ligands, may constitute an important model for studying ligand-biased signaling.

  1. Identification of Carboxylate, Phosphate, and Phenoxide Functionalities in Deprotonated Molecules Related to Drug Metabolites via Ion-Molecule Reactions with water and Diethylhydroxyborane

    Science.gov (United States)

    Zhu, Hanyu; Ma, Xin; Kong, John Y.; Zhang, Minli; Kenttämaa, Hilkka I.

    2017-10-01

    Tandem mass spectrometry based on ion-molecule reactions has emerged as a powerful tool for structural elucidation of ionized analytes. However, most currently used reagents were designed to react with protonated analytes, making them suboptimal for acidic analytes that are preferentially detected in negative ion mode. In this work we demonstrate that the phenoxide, carboxylate, and phosphate functionalities can be identified in deprotonated molecules by use of a combination of two reagents, diethylmethoxyborane (DEMB) and water. A novel reagent introduction setup that allowed DEMB and water to be separately introduced into the ion trap region of the mass spectrometer was developed to facilitate fundamental studies of this reaction. A new reagent, diethylhydroxyborane (DEHB), was generated inside the ion trap by hydrolysis of DEMB on introduction of water. Most carboxylates and phenoxides formed a DEHB adduct, followed by addition of one water molecule and subsequent ethane elimination (DEHB adduct +H2O - CH3CH3) as the major product ion. Phenoxides with a hydroxy group adjacent to the deprotonation site and phosphates formed a DEHB adduct, followed by ethane elimination (DEHB adduct - CH3CH3). Deprotonated molecules with strong intramolecular hydrogen bonds or without the aforementioned functionalities, including sulfates, were unreactive toward DEHB/H2O. Reaction mechanisms were explored via isotope labeling experiments and quantum chemical calculations. The mass spectrometry method allowed the differentiation of phenoxide-, carboxylate-, phosphate-, and sulfate-containing analytes. Finally, it was successfully coupled with high-performance liquid chromatography for the analysis of a mixture containing hymecromone, a biliary spasm drug, and its three possible metabolites. [Figure not available: see fulltext.

  2. Effect of structure, particle size and relative concentration of Eu3+ and Tb3+ ions on the luminescence properties of Eu3+ co-doped Y2O3:Tb nanoparticles

    International Nuclear Information System (INIS)

    Mukherjee, S; Sudarsan, V; Vatsa, R K; Tyagi, A K; Godbole, S V; Kadam, R M; Bhatta, U M

    2008-01-01

    Eu 3+ co-doped Y 2 O 3 :Tb nanoparticles were prepared by the combustion method and characterized for their structural and luminescence properties as a function of annealing temperatures and relative concentration of Eu 3+ and Tb 3+ ions. For Y 2 O 3 :Eu,Tb nanoparticles annealed at 600 and 1200 deg. C, variation in the relative intensity of excitation transitions between the 7 F 6 ground state and low spin and high spin 4f 7 5d 1 excited states of Tb 3+ is explained due to the combined effect of distortion around Y 3+ /Tb 3+ in YO 6 /TbO 6 polyhedra and the size of the nanoparticles. Increase in relative intensity of the 285 nm peak (spin-allowed transition denoted as peak B) with respect to the 310 nm peak (spin-forbidden transition denoted as peak A) with decrease of Tb 3+ concentration in the Y 2 O 3 :Eu,Tb nanoparticles heated at 1200 deg. C is explained based on two competing effects, namely energy transfer from Tb 3+ to Eu 3+ ions and quenching among the Tb 3+ ions. Back energy transfer from Tb 3+ to Eu 3+ in these nanoparticles is found to be very poor

  3. Fundamental processes in ion plating

    International Nuclear Information System (INIS)

    Mattox, D.M.

    1980-01-01

    Ion plating is a generic term applied to film deposition processes in which the substrate surface and/or the depositing film is subjected to a flux of high energy particles sufficient to cause changes in the interfacial region of film properties compared to a nonbombarded deposition. Ion plating is being accepted as an alternative coating technique to sputter deposition, vacuum evaporation and electroplating. In order to intelligently choose between the various deposition techniques, the fundamental mechanisms, relating to ion plating, must be understood. This paper reviews the effects of low energy ion bombardment on surfaces, interface formation and film development as they apply to ion plating and the implementation and applications of the ion plating process

  4. Ion detection in mass spectrometry

    International Nuclear Information System (INIS)

    Bolbach, Gerard

    2016-03-01

    This course aims at providing some elements for a better understanding of ion detectors used in mass spectrometers, of their operations, and of their limitations. A first part addresses the functions and properties of an ideal detector, how to detect ions in gas phase, and particle detectors and ion detectors used in mass spectrometry. The second part proposes an overview of currently used detectors with respect to their operation principle: detection from the ion charge (Faraday cylinder), detection by inductive effects (FTICR, Fourier Transform Ion Cyclotron Resonance), and detection by secondary electron emission. The third part discusses the specificities of secondary electron emission. The fourth one addresses operating modes and parameters related to detectors. The sixth part proposes a prospective view on future detectors by addressing the following issues: cryo-detector, inductive effect and charge detectors, ion detection and nano materials

  5. Ion acoustic waves in one- and two-negative ion species plasmas

    International Nuclear Information System (INIS)

    Ichiki, Ryuta; Shindo, Masako; Yoshimura, Shinji; Watanabe, Tsuguhiro; Kawai, Yoshinobu

    2001-01-01

    Ion acoustic waves in multi-ion plasmas including two negative ion species are investigated both numerically and experimentally. Numerically, the kinetic dispersion relation in two-negative ion plasmas is investigated. There are three modes of the ion acoustic waves in two-negative ion plasmas. In an Ar + -F - -SF 6 - plasma, only one of the three modes is dominant, regardless of the values of the electron and the ion temperatures. In a Xe + -F - -SF 6 - plasma, on the other hand, two modes can be important for a certain range of the electron-ion temperature ratio. The results also imply the possibility of the coexistence of the fast mode and the slow mode in one-negative ion plasmas. Experimentally, ion acoustic waves are observed in an Ar + -F - -SF 6 - plasma and are found to show a mode transition that agrees with the theoretical prediction for one of the three ion acoustic modes

  6. Field ion microscopy

    International Nuclear Information System (INIS)

    Ramanathan, D.

    1975-01-01

    The basic features of the Field-Ion Microscope (FIM) and the theory of image formation are explained. Design parameters of the FIM, factors limiting its resolution, interpretation of the image, etc are briefly outlined. Relative merits of the various imaging gases and the applications of the FIM are also covered. (K.B.)

  7. Periodic organosilica hollow nanospheres as anode materials for lithium ion rechargeable batteries.

    Science.gov (United States)

    Sasidharan, Manickam; Nakashima, Kenichi; Gunawardhana, Nanda; Yokoi, Toshiyuki; Ito, Masanori; Inoue, Masamichi; Yusa, Shin-ichi; Yoshio, Masaki; Tatsumi, Takashi

    2011-11-01

    Polymeric micelles with core-shell-corona architecture have been found to be the efficient colloidal templates for synthesis of periodic organosilica hollow nanospheres over a broad pH range from acidic to alkaline media. In alkaline medium, poly (styrene-b-[3-(methacryloylamino)propyl] trimethylammonium chloride-b-ethylene oxide) (PS-PMAPTAC-PEO) micelles yield benzene-silica hollow nanospheres with molecular scale periodicity of benzene groups in the shell domain of hollow particles. Whereas, an acidic medium (pH 4) produces diverse hollow particles with benzene, ethylene, and a mixture of ethylene and dipropyldisulfide bridging functionalities using poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-PVP-PEO) micelles. These hollow particles were thoroughly characterized by powder X-ray diffraction (XRD), dynamic light scattering (DLS), thermogravimetric analysis (TG/DTA), Fourier transformation infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), magic angle spinning-nuclear magnetic resonance ((29)Si MAS NMR and (13)CP-MAS NMR), Raman spectroscopy, and nitrogen adsorption/desorption analyses. The benzene-silica hollow nanospheres with molecular scale periodicity in the shell domain exhibit higher cycling performance of up to 300 cycles in lithium ion rechargeable batteries compared with micron-sized dense benzene-silica particles.

  8. Rearrangement reactions in ion-ion and ion-atom collisions: results and problems

    Energy Technology Data Exchange (ETDEWEB)

    Presnyakov, L.P. [Lebedev Physical Institute, Moscow (Russian Federation); Tawara, H.

    1997-01-01

    Recent experimental and theoretical results are discussed for ionic collisions with large cross sections at intermediate and small energies of the relative motion. Single- and double-electron removal from H{sup -} ions in slow collisions with other ions is considered in more details. The theoretical methods are discussed from the viewpoint of general requirements of scattering theory. (author)

  9. Ion channeling

    International Nuclear Information System (INIS)

    Erramli, H.; Blondiaux, G.

    1994-01-01

    Channeling phenomenon was predicted, many years ago, by stark. The first channeling experiments were performed in 1963 by Davies and his coworkers. Parallely Robinson and Oen have investigated this process by simulating trajectories of ions in monocrystals. This technique has been combined with many methods like Rutherford Backscattering Spectrometry (R.B.S.), Particles Induced X-rays Emission (P.I.X.E) and online Nuclear Reaction (N.R.A.) to localize trace elements in the crystal or to determine crystalline quality. To use channeling for material characterization we need data about the stopping power of the incident particle in the channeled direction. The ratios of channeled to random stopping powers of silicon for irradiation in the direction have been investigated and compared to the available theoretical results. We describe few applications of ion channeling in the field of materials characterization. Special attention is given to ion channeling combined with Charged Particle Activation Analysis (C.P.A.A.) for studying the behaviour of oxygen atoms in Czochralski silicon lattices under the influence of internal gettering and in different gaseous atmospheres. Association between ion channeling and C.P.A.A was also utilised for studying the influence of the growing conditions on concentration and position of carbon atoms at trace levels in the MOVPE Ga sub (1-x) Al sub x lattice. 6 figs., 1 tab., 32 refs. (author)

  10. Ion source

    International Nuclear Information System (INIS)

    1977-01-01

    The specifications of a set of point-shape electrodes of non-corrodable material that can hold a film of liquid material of equal thickness is described. Contained in a jacket, this set forms an ion source. The electrode is made of tungsten with a glassy carbon layer for insulation and an outer layer of aluminium-oxide ceramic material

  11. Models including electron correlation in relation to Fock's proposed expansion of the ground-state wave function of He-like atomic ions

    Energy Technology Data Exchange (ETDEWEB)

    Glasser, M. L.; March, N. H.; Nieto, L. M. [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, ES-47011 Valladolid, Spain and Department of Physics, Clarkson University, Potsdam, New York 13699 (United States); Department of Physics, University of Antwerp, BE-2020 Antwerp, Belgium and Department of Theoretical Chemistry, University of Oxford, Oxford OX1 2JD (United Kingdom); Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, ES-47011 Valladolid (Spain)

    2011-12-15

    Here attention is first drawn to the importance of gaining insight into Fock's early proposal for expanding the ground-state wave function for He-like atomic ions in hyperspherical coordinates. We approach the problem via two solvable models, namely, (i) the s-term model put forth by Temkin [Phys. Rev. 126, 130 (1962)] and (ii) the Hookean atom model proposed by Kestner and Sinanoglu [Phys. Rev. 128, 2687 (1962)]. In both cases the local kinetic energy can be obtained explicitly in hyperspherical coordinates. Separation of variables occurs in both model wave functions, though in a different context in the two cases. Finally, a k-space formulation is proposed that should eventually result in distinctive identifying characteristics of Fock's nonanalyticities for He-like atomic ions when both electrons are close to the nucleus.

  12. Investigation of reactivity of inorganic free radicals relative to ferrocyanide- and octacyanomolybdate-ions in aqueous solutions by the method of pulse radiolysis

    International Nuclear Information System (INIS)

    Gogolev, A.V.; Fedoseev, A.M.; Makarov, I.F.; Pikaev, A.K.

    1989-01-01

    In aqueous solutions by the method of pulse radiolysis (dose per impulse-7.96-47.8 Gy, electron energy-5 MeV) the reactivity of Cl 2 - , Br 2 - , I 2 - , (SCN) 2 - , CO 3 - , SeO 3 - , SO 4 - radicals towards ferrocyanide ions and of Br 2 - , CO 3 - , SO 4 - radicals tawards octacyanomolybdate ions is studied. Linear dependence of rate constant logarithm of Cl 2 - , Br 2 - , I 2 - reactions with cyanide complexes on the difference of redox potentials of reacting particles ΔE 0 is obtained. Radicals containing oxygen react with cyanide complexes more rapidly than can be expected on the basis of ΔE 0 values. The effect of solution ionic strength, charge of reacting particles and radical nature on the reaction rate is discussed

  13. Imaging properties of scintillators for heavy-ion-beams and related model calculations; Abbildungseigenschaften von Szintillatoren fuer Schwerionenstrahlen und diesbezuegliche Modellrechnungen

    Energy Technology Data Exchange (ETDEWEB)

    Guetlich, Eiko

    2011-08-15

    This thesis is treating the imaging properties of scintillating screens for high-current ion beams as delivered by the UNILAC at the GSI Helmholtzzentrum fuer Schwerionenforschung in Darmstadt, Germany. Scintillating screens are mainly used to measure and rate the tansversal beam parameters in nearly every particle accelerator. During daily operation, scintillating screens can be used to determine and optimize the position of the beam inside the beam-pipe as well as the transversal intensity distribution. Although scintillating screens are widely used in many measurement systems, their imaging properties are not well characterized. Within the framework of this thesis, accelerator based experiments were planed and carried out which allowed to compare the results of beam profile measurements of the different materials with reference methods. Parameters such as the screen temperature and particle energies have been varied. Additionaly, possible image distortions within the optical system have been investigated. To determine the influence of the emission spectra of the screens onto the profile measurement a novel experimental setup for the spectroscopic investigations has been established. The setup allows to investigate the emission spectrum along one spatial axes on the beamspot. The investigations focus on ceramic materials such as zirconium oxide doped e.g. with Mg (ZrO{sub 2}:Mg) or aluminium oxide (Al{sub 2}O{sub 3}). The materials have been irradiated with different ion species (e.g. Calcium and Uranium) with kinetic energies of 4.8 MeV/u (10% c) and 11.4 MeV (15% c). The results for different parameters are discussed and interpreted. The measured beam profiles show dependences of four parameters: - The material itself. - The screen temperature. - The accumulated fluence [ (Ions)/(cm{sup 2})]. - The excitation density [(Electron-Hole-Pairs)/(cm{sup 3})], which is proportional to the dose rate [(J)/(kg . s)] within the volume element. Among the above, the last

  14. Measurement of the ion drag force on falling dust particles and its relation to the void formation in complex (dusty) plasmas

    International Nuclear Information System (INIS)

    Zafiu, C.; Melzer, A.; Piel, A.

    2003-01-01

    Experiments on the quantitative determination of the weaker forces (ion drag, thermophoresis, and electric field force) on free-falling dust particles in a rf discharge tube are presented. The strongest force, gravity, is balanced by gas friction and the weaker forces are investigated in the radial (horizontal) plane. Under most discharge conditions, the particles are found to be expelled from the central plasma region. A transition to a situation where the falling particles are focused into the plasma center is observed at low gas pressures using small particles. These investigations allow a quantitative understanding of the mechanism of unwanted dust-free areas (so-called voids) in dusty plasmas under microgravity. Good quantitative agreement with standard models of the ion drag is found

  15. Graphene defects induced by ion beam

    Science.gov (United States)

    Gawlik, Grzegorz; Ciepielewski, Paweł; Baranowski, Jacek; Jagielski, Jacek

    2017-10-01

    The CVD graphene deposited on the glass substrate was bombarded by molecular carbon ions C3+ C6+ hydrocarbon ions C3H4+ and atomic ions He+, C+, N+, Ar+, Kr+ Yb+. Size and density of ion induced defects were estimated from evolution of relative intensities of Raman lines D (∼1350 1/cm), G (∼1600 1/cm), and D‧ (∼1620 1/cm) with ion fluence. The efficiency of defect generation by atomic ions depend on ion mass and energy similarly as vacancy generation directly by ion predicted by SRIM simulations. However, efficiency of defect generation in graphene by molecular carbon ions is essentially higher than summarized efficiency of similar group of separate atomic carbon ions of the same energy that each carbon ion in a cluster. The evolution of the D/D‧ ratio of Raman lines intensities with ion fluence was observed. This effect may indicate evolution of defect nature from sp3-like at low fluence to a vacancy-like at high fluence. Observed ion graphene interactions suggest that the molecular ion interacts with graphene as single integrated object and should not be considered as a group of atomic ions with partial energy.

  16. Ion nitriding of aluminium

    International Nuclear Information System (INIS)

    Fitz, T.

    2002-09-01

    The present study is devoted to the investigation of the mechanism of aluminium nitriding by a technique that employs implantation of low-energy nitrogen ions and diffusional transport of atoms. The nitriding of aluminium is investigated, because this is a method for surface modification of aluminium and has a potential for application in a broad spectrum of fields such as automobile, marine, aviation, space technologies, etc. However, at present nitriding of aluminium does not find any large scale industrial application, due to problems in the formation of stoichiometric aluminium nitride layers with a sufficient thickness and good quality. For the purposes of this study, ion nitriding is chosen, as an ion beam method with the advantage of good and independent control over the process parameters, which thus can be related uniquely to the physical properties of the resulting layers. Moreover, ion nitriding has a close similarity to plasma nitriding and plasma immersion ion implantation, which are methods with a potential for industrial application. (orig.)

  17. Relation between hard photon production and impact parameter in heavy ion collisions at intermediate energies; Dependance de la production de photons durs avec le parametre d`impact dans les collisions entre ions lourds aux energies intermediaires

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Garcia, G.

    1994-06-01

    Hard photons produced in heavy-ions collisions at intermediate energies have been used in order to study hot and compresses nuclear matter created in these collisions (at Ganil). It was found that Bremsstrahlung radiation emitted in np collisions is the main mechanism of hard-photon production for the whole range of impact parameter. Moreover, it was observed a substantial decrease of the hardness of hard-photon spectrum. The BUU model reproduces very well the experimental results, showing that the hardness of the spectrum reflects, mainly, nuclear-matter compression in the first stage of the collision. A new method was developed to measure the density of the nuclear matter created at the beginning of the collision. BUU results and some experimental evidences point out that a significant contribution of hard photons are produced in the last stage of the collision: thermal hard photons. These photons are sensitive to the density oscillation of nuclear matter. Its production cross-section will constitute a measurement of the compressibility of nuclear matter and its spectrum a measure of the temperature. (from author) 64 figs., 60 refs.

  18. Ion-ion collisions and ion storage rings

    International Nuclear Information System (INIS)

    Mowat, J.R.

    1988-01-01

    Improved understanding of fundamental ion-ion interactions is expected to emerge from research carried out with ion storage rings. In this short survey the significant advantages and unique features that make stored ions useful targets for collision experiments are reviewed and discussed. It is pointed out that improvements to existing ion-ion experiments, as well as qualitatively new experiments, should occur over the next few years as ion storage rings become available for atomic physics. Some new experiments are suggested which are difficult if not impossible with present-day technology, but which seem feasible at storage rings facilities. (orig.)

  19. Ion exchange currents in vacuum accelerator tubes

    International Nuclear Information System (INIS)

    Eastham, D.A.; Thorn, R.

    1978-01-01

    Ion exchange currents (microdischarges) have been observed in short lengths of accelerator tube. The occurrence of these discharges can be related to the trajectories of ions in the tube. High-resolution mass spectra of the negative and positive ion components have been obtained. (author)

  20. Ion-exchange chromatographic protein refolding

    NARCIS (Netherlands)

    Freydell, E.; Wielen, van der L.; Eppink, M.H.M.; Ottens, M.

    2010-01-01

    The application of ion-exchange (IEX) chromatography to protein refolding (IExR) has been successfully proven, as supported by various studies using different model proteins, ion-exchange media and flow configurations. Ion-exchange refolding offers a relatively high degree of process

  1. Effect of solvents on relation of intensities of bands of luminescence spectra of terbium and dysprosium ions in solutions of their complexes with acetoacetic ester

    International Nuclear Information System (INIS)

    Kononenko, L.I.; Bel'tyukova, S.V.; Meshkova, S.B.; Kravchenko, T.B.; Poluehktov, N.S.

    1978-01-01

    An investigation is made of the effect of different solvents on the ratio of the intensity of luminescence spectrum bands of terbium and dysprosium ions, corresponding and not corresponding to ''supersensitive'' transitions in complex compounds with acetoacetic ether. A dependence is established between these values and the dielectric constant of the solvent, and also parallels in their changes, which indicate the similar manifestation of the effect of solvents in both elements. A correlation is observed between ratios of the intensity of luminescence spectrum bands and values of forces of neodymium complex absorption band oscillators in different solvents

  2. External excitation of ion cyclotron drift waves in a two-ion species plasma

    International Nuclear Information System (INIS)

    Kando, M.; Ikezawa, S.; Sugai, H.

    1984-01-01

    Ion cyclotron drift waves propagating across a density gradient and a magnetic field have been excited externally in a two-ion species plasma, with its concentration ratio controlled. The measured dispersion relations agree with the theoretical predictions. (author)

  3. Medium-energy ion reflection from solids

    CERN Document Server

    Mashkova, ES

    1985-01-01

    ``Medium-Energy Ion Reflection from Solids'' analyses the results of experimental, theoretical and computer investigations on the process of scattering of ions by solid surfaces. Surface scattering is a relatively young and rapidly developing branch of the physics of atomic collisions and the literature on this subject has rapidly grown.As the first monograph devoted specifically to surface scattering of ions, this book is directed at scientists involved in ion-solid interaction studies.

  4. Product ion diffusion in flowing afterglows

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M J; Stock, H M.P. [University Coll. of Wales, Aberystwyth (UK). Dept. of Physics

    1975-11-11

    An analysis of the variation of product ion signals in flowing after-glow experiments is presented. It is shown that under certain conditions the relative variation of a single product ion yields not only the total reaction rate coefficients but also the ambipolar diffusion coefficient of the product ion in the buffer gas. Theory is compared with experiment for a number of ion-molecule and Penning reactions.

  5. Relation between plasmons and the valence-band density-of-states in polymethylmethacrylate - influence of ion irradiation on damage selectivity

    International Nuclear Information System (INIS)

    Moliton, J.P.; Jussiaux, C.; Trigaud, T.; Lazzaroni, R.; Lhost, O.; Bredas, J.L.; Kihn, Y.; Sevely, J.

    1996-01-01

    A physical model is presented that aims at rationalizing the selectivity of bond breakage observed when polymethylmethacrylate is irradiated by ions in the 10-500 keV energy range. This model, previously proposed by Brandt and Ritchie, is based on electronic collective effects. The coupling between the pure plasma oscillation at omega(p) and the oscillation of free electrons at [omega(k0)(2)](1/2) makes the whole electronic population resonant at the frequency omega(rp) = (omega(p)(2) + [omega(k0)(2)])(1/2). By computing the valence-band density of states, we calculate [omega(k0)(2)] and then deduce the theoretical value of omega(rp). On the other hand, we provide an experimental measurement of omega(rp) and study its dependence on ion fluence by electron-energy-loss spectroscopy. The validity of the model of Brandt and Ritchie is then discussed in the light of both theoretical and experimental data. (author)

  6. NASA Aerospace Flight Battery Program: Generic Safety, Handling and Qualification Guidelines for Lithium-Ion (Li-Ion) Batteries; Availability of Source Materials for Lithium-Ion (Li-Ion) Batteries; Maintaining Technical Communications Related to Aerospace Batteries (NASA Aerospace Battery Workshop). Volume 2, Part 1

    Science.gov (United States)

    Manzo, Michelle A.; Brewer, Jeffrey C.; Bugga, Ratnakumar V.; Darcy, Eric C.; Jeevarajan, Judith A.; McKissock, Barbara I.; Schmitz, Paul C.

    2010-01-01

    This NASA Aerospace Flight Battery Systems Working Group was chartered within the NASA Engineering and Safety Center (NESC). The Battery Working Group was tasked to complete tasks and to propose proactive work to address battery related, agency-wide issues on an annual basis. In its first year of operation, this proactive program addressed various aspects of the validation and verification of aerospace battery systems for NASA missions. Studies were performed, issues were discussed and in many cases, test programs were executed to generate recommendations and guidelines to reduce risk associated with various aspects of implementing battery technology in the aerospace industry. This report contains the Appendices to the findings from the first year of the program's operations.

  7. Molecular cloning of ion channels in Felis catus that are related to periodic paralyses in man: a contribution to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis

    Directory of Open Access Journals (Sweden)

    Marlyn Zapata

    2014-07-01

    Full Text Available Neck ventroflexion in cats has different causes; however, the most common is the hypokalemia associated with flaccid paralysis secondary to chronic renal failure. In humans, the most common causes of acute flaccid paralysis are hypokalemia precipitated by thyrotoxicosis and familial forms linked to mutations in sodium, potassium, and calcium channel genes. Here, we describe the sequencing and analysis of skeletal muscle ion channels in Felis catus that could be related to periodic paralyses in humans, contributing to the understanding of the genetic susceptibility to feline neck ventroflexion and paralysis. We studied genomic DNA from eleven cats, including five animals that were hyperthyroid with hypokalemia, although only one presented with muscle weakness, and six healthy control domestic cats. We identified the ion channel ortholog genes KCNJ2, KCNJ12, KCNJ14, CACNA1S and SCN4A in the Felis catus genome, together with several polymorphic variants. Upon comparative alignment with other genomes, we found that Felis catus provides evidence for a high genomic conservation of ion channel sequences. Although we hypothesized that neck ventroflexion in cats could be associated with a thyrotoxic or familial periodic paralysis channel mutation, we did not identify any previously detected human channel mutation in the hyperthyroid cat presenting hypokalemia. However, based on the small number of affected cats in this study, we cannot yet rule out this molecular mechanism. Notwithstanding, hyperthyroidism should still be considered as a differential diagnosis in hypokalemic feline paralysis.

  8. Correlation between SnO{sub 2} nanocrystals and optical properties of Eu{sup 3+} ions in SiO{sub 2} matrix: Relation of crystallinity, composition, and photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, Bui Quang [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Ha, Ngo Ngoc, E-mail: hann@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Khiem, Tran Ngoc, E-mail: khiem@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Chien, Nguyen Duc [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); School of Engineering Physics (SEP), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam)

    2015-07-15

    We report characteristics and optical properties of Eu{sup 3+}-doped SnO{sub 2} nanocrystals dispersed in SiO{sub 2} matrix. Samples are prepared by the sol–gel method. Crystallinity of SnO{sub 2} nanocrystals is examined by X-ray diffraction experiments. At annealing temperatures from 900 to 1200 °C, we observe the formation of single tetragonal rutile structure of SnO{sub 2} nanocrystals. Average sizes of SnO{sub 2} nanocrystals within 3–7 nm are estimated by Debye–Scherrer equation. Intense photoluminescent spectra of Eu{sup 3+} ions consist of a series of resolved emission bands within 570–645 nm, which are varied with different sample-preparation conditions. We show the efficient excitation process of Eu{sup 3+} ions through SnO{sub 2} nanocrystals in the materials. Microscopic structure of SnO{sub 2} nanoparticles and optical properties of Eu{sup 3+} ions are also presented and discussed. - Highlights: • Thin layers of Eu{sup 3+} doped SnO{sub 2} nanocrystals dispersed in SiO{sub 2} were prepared by sol-gel method and spin-coating process. • Formation of single-phase tetragonal rutile structure of SnO{sub 2} nanocrystals and highly efficient optical excitation of the Eu{sup 3+} dopants were exhibited. • Relations of the crystallinity and composition of SnO{sub 2} and optical properties of Eu{sup 3+} dopants were comprehensively investigated and presented. • Allocations of major optically-active Eu{sup 3+} ions in the materials were deduced from their emission bands.

  9. Recent negative ion source developments

    International Nuclear Information System (INIS)

    Alton, G.D.

    1978-01-01

    This report describes recent results obtained from studies associated with the development of negative ion sources which utilize sputtering in a diffuse cesium plasma as a means of ion beam generation. Data are presented which relate negative ion yield and important operational parameters such as cesium oven temperature and sputter probe voltage from each of the following sources: (1) A source based in principle according to the University of Aarhus design and (2) an axial geometry source. The important design aspects of the sources are given--along with a list of the negative ion intensities observed to date. Also a qualitative description and interpretation of the negative ion generation mechanism in sources which utilize sputtering in the presence of cesium is given

  10. Ion Beam Extraction by Discrete Ion Focusing

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (900) and methods are disclosed for ion beam extraction. In an implementation, the apparatus includes a plasma source (or plasma) (802) and an ion extractor (804). The plasma source is adapted to generate ions and the ion extractor is immersed in the plasma source to extract a fracti...

  11. Response of thermal ions to electromagnetic ion cyclotron waves

    Science.gov (United States)

    Anderson, B. J.; Fuselier, S. A.

    1994-01-01

    Electromagnetic ion cyclotron waves generated by 10 - 50 keV protons in the Earth's equatorial magnetosphere will interact with the ambient low-energy ions also found in this region. We examine H(+) and He(+) distribution functions from approx. equals 1 to 160 eV using the Hot Plasma Composition Experiment instrument on AMPTE/CCE to investigate the thermal ion response to the waves. A total of 48 intervals were chosen on the basis of electromagnetic ion cyclotron (EMIC) wave activity: 24 with prevalent EMIC waves and 24 with no EMIC waves observed on the orbit. There is a close correlation between EMIC waves and perpendicular heated ion distributions. For protons the perpendicular temperature increase is modest, about 5 eV, and is always observed at 90 deg pitch angles. This is consistent with a nonresonant interaction near the equator. By contrast, He(+) temperatures during EMIC wave events averaged 35 eV and sometimes exceeded 100 eV, indicating stronger interaction with the waves. Furthermore, heated He(+) ions have X-type distributions with maximum fluxes occurring at pitch angles intermediate between field-aligned and perpendicular directions. The X-type He(+) distributions are consistent with a gyroresonant interaction off the equator. The concentration of He(+) relative to H(+) is found to correlate with EMIC wave activity, but it is suggested that the preferential heating of He(+) accounts for the apparent increase in relative He(+) concentration by increasing the proportion of He(+) detected by the ion instrument.

  12. Bill project authorizing the approval of the convention related to the construction and the exploitation of an infrastructure for the research on anti-protons and ions in Europe - Impact study

    International Nuclear Information System (INIS)

    2012-06-01

    This impact study first indicates the objectives of the convention related to the construction and the exploitation of an infrastructure for the research on anti-protons and ions in Europe (creation of the FAIR company in a similar way as the one retained for the XFEL installation). It discusses the scientific, economic, financial, social, environmental, legal and administrative consequences of this convention, and also evokes the elements of international context. It briefly recalls the history of negotiations which started in 2004 after internal preliminary studies performed in Germany. It indicates the countries who signed the convention

  13. Relativistic heavy ion physics

    International Nuclear Information System (INIS)

    Hansen, O.

    1985-01-01

    In the fall of 1986 beams of heavy ions up to A ∼ 40 at total energies up to E ∼ 225 GeV/-nucleon will become available for experiments at CERN (60 and 225 GeV/nucleon) and at Brookhaven (15.5 GeV/nucleon). Are these energies interesting in relation to the ideas of creating quark deconfinement? An energy consideration of the planned experiments is presented, as well as a description of the experimental arrangement. (Auth.)

  14. Fungitoxicity of metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Somers, E

    1961-01-01

    The in vitro fungistatic activity of some twenty-four metal cations has been determine against Alternaria tenuis and Botrytis fabae. The metal salts, mainly nitrates, were tested in aqueous solution without added spore germination stimulant. The logarithm of the metal ion concentration at the ED 50 value has been found to conform to the exponenttial relationship with electronegativity proposed by Danielli and Davies (1951). These results are discussed in relation to the site of action of metal cations on the fungal cell.

  15. ION GUN

    Science.gov (United States)

    Dandl, R.A.

    1961-10-24

    An ion gun is described for the production of an electrically neutral ionized plasma. The ion gun comprises an anode and a cathode mounted in concentric relationship with a narrow annulus between. The facing surfaces of the rear portions of the anode and cathode are recessed to form an annular manifold. Positioned within this manifold is an annular intermediate electrode aligned with the an nulus between the anode and cathode. Gas is fed to the manifold and an arc discharge is established between the anode and cathode. The gas is then withdrawn from the manifold through the annulus between the anode and cathode by a pressure differential. The gas is then ionized by the arc discharge across the annulus. The ionized gas is withdrawn from the annulus by the combined effects of the pressure differential and a collimating magnetic field. In a 3000 gauss magnetic field, an arc voltage of 1800 volts, and an arc current of 0.2 amp, a plasma of about 3 x 10/sup 11/ particles/cc is obtained. (AEC)

  16. Heavy ions

    CERN Multimedia

    CERN. Geneva; Antinori, Federico

    2001-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  17. Heavy ions

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  18. CO2 laser photolysis of clustered ions, (1)

    International Nuclear Information System (INIS)

    Ikezoe, Yasumasa; Soga, Takeshi; Suzuki, Kazuya; Ohno, Shin-ichi.

    1990-09-01

    Vibrational excitation and the following decomposition of cluster ions by CO 2 laser photons are studied. Characteristics of the cluster ion and the CO 2 laser photon are summarized in their relation to the photolysis of cluster ions. An apparatus was installed, which is composed of (1) corona discharge-jet expansion section (formation of cluster ions), (2) CO 2 laser section (photolysis of cluster ions), and (3) mass spectrometer section. Experimental results of ammonia cluster ions were described. Effects of repeller voltage, shape of repellers, and adiabatic cooling are examined on the formation of ammonia cluster ions by corona discharge-jet expansion method. Collisional dissociation of cluster ions was observed at high repeller voltages. Size distribution of the ammonia cluster ion is discussed in connection with the temperature of cluster ions. Intensity of CO 2 laser was related to decomposition yield of cluster ions. (author)

  19. Highly Stripped Ion Sources for MeV Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady

    2009-06-30

    Original technical objectives of CRADA number PVI C-03-09 between BNL and Poole Ventura, Inc. (PVI) were to develop an intense, high charge state, ion source for MeV ion implanters. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MV LINAC is used for acceleration of a few rnA. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform (de acceleration) to generate high-energy ion beams for implantation. This de acceleration of ions will be far more efficient (in energy utilization). The resultant implanter will be smaller in size. It will generate higher quality ion beams (with lower emittance) for fabrication of superior semiconductor products. In addition to energy and cost savings, the implanter will operate at a lower level of health risks associated with ion implantation. An additional aim of the project was to producing a product that can lead to long­ term job creation in Russia and/or in the US. R&D was conducted in two Russian Centers (one in Tomsk and Seversk, the other in Moscow) under the guidance ofPVI personnel and the BNL PI. Multiple approaches were pursued, developed, and tested at various locations with the best candidate for commercialization delivered and tested at on an implanter at the PVI client Axcelis. Technical developments were exciting: record output currents of high charge state phosphorus and antimony were achieved; a Calutron-Bemas ion source with a 70% output of boron ion current (compared to 25% in present state-of-the-art). Record steady state output currents of higher charge state phosphorous and antimony and P ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb {sup 4 +}, Sb{sup 5+}, and Sb{sup 6+} respectively. Ultimate commercialization goals did not succeed (even though a number of the products like high

  20. Systems and Methods for Ejection of Ions from an Ion Trap

    Science.gov (United States)

    Cooks, Robert Graham (Inventor); Snyder, Dalton (Inventor)

    2018-01-01

    The invention generally relates to systems and methods for ejection of ions from an ion trap. In certain embodiments, systems and methods of the invention sum two different frequency signals into a single summed signal that is applied to an ion trap. In other embodiments, an amplitude of a single frequency signal is modulated as the single frequency signal is being applied to the ion trap. In other embodiments, a first alternating current (AC) signal is applied to an ion trap that varies as a function of time, while a constant radio frequency (RF) signal is applied to the ion trap.

  1. Heavy Ion Physics at LHC

    CERN Document Server

    Valenti, G.

    2002-01-01

    The study of heavy ion interactions constitutes an important part of the experimental program outlined for the Large Hadron Collider under construction at CERN and expected to be operational by 2006. ALICE 1 is the single detector having the capabilities to explore at the same time most of the characteristics of high energy heavy ion interactions. Specific studies of jet quenching and quarkonia production, essentially related to µ detection are also planned by CMS 2 .

  2. Workshop on transport for a common ion driver

    International Nuclear Information System (INIS)

    Olson, C.C.; Lee, E.; Langdon, B.

    1994-01-01

    This report contains research in the following areas related to beam transport for a common ion driver: multi-gap acceleration; neutralization with electrons; gas neutralization; self-pinched transport; HIF and LIF transport, and relevance to common ion driver; LIF and HIF reactor concepts and relevance to common ion driver; atomic physics for common ion driver; code capabilities and needed improvement

  3. Resonance cones below the ion cyclotron frequency: theory and experiment

    International Nuclear Information System (INIS)

    Bellan, P.

    1976-03-01

    The resonance cones existing below the ion cyclotron frequency, ω/sub c/sub i//, are shown, theoretically and experimentally, to be the asymptotes of hyperbolic constant-phase surfaces of low-frequency ion acoustic waves. Above ω/sub c/sub i// the surfaces transform into ellipses that are related to the electrostatic ion cyclotron waves and ion acoustic waves

  4. Electrochemical behavior of phytochelatins and related peptides at the hanging mercury drop electrode in the presence of cobalt(II) ions.

    Science.gov (United States)

    Dorcák, Vlastimil; Sestáková, Ivana

    2006-01-01

    Direct current voltammetry and differential pulse voltammetry have been used to investigate the electrochemical behaviour of two phytochelatins: heptapeptide (gamma-Glu-Cys)3-Gly and pentapeptide (gamma-Glu-Cys)2-Gly, tripeptide glutathione gamma-Glu-Cys-Gly and its fragments: dipeptides Cys-Gly and gamma-Glu-Cys at the hanging mercury drop electrode in the presence of cobalt(II) ions. Most interesting results were obtained with direct current voltammetry in the potential region of -0.80 V up to -1.80 V. Differential pulse voltammetry of the same solutions of Co(II) with peptides gives more complicated voltammograms with overlapping peaks, probably in connection with the influence of adsorption at slow scan rates necessarily used in this method. However, in using Brdicka catalytic currents for analytical purposes, differential pulse voltammograms seem to be more helpful. Presented investigations have shown that particularly the prewave of cobalt(II) allows distinguishing among phytochelatins, glutathione, and its fragments.

  5. Negative ion sourcery

    International Nuclear Information System (INIS)

    Os, C.F.A. van.

    1989-01-01

    The work described in this thesis is involved by current research programs in the field of nuclear-fusion. A brief introduction to fusion is given, anticipated problems related to current drive of the fusion plasma are pinpointed and probable suggestions to overcome these problems are described. One probable means for current drive is highlighted; Neutral Beam Injection (NBI). This is based on injecting a 1 MeV neutral hydrogen or deuterium beam into a fusion plasma. Negative ions are needed as primary particles because they can easily be neutralized at 1 MeV. The two current schemes for production of negative ions are described, volume production and negative surface ionization. The latter method is extensively studied in this thesis. (author). 171 refs.; 55 figs.; 7 tabs

  6. Ion beam monitoring

    International Nuclear Information System (INIS)

    McKinney, C.R.

    1980-01-01

    An ion beam analyzer is specified, having an ion source for generating ions of a sample to be analyzed, means for extracting the sample ions, means for focusing the sample ions into a beam, separation means positioned along the ion beam for selectively deflecting species of ions, and means for detecting the selected species of ions. According to the specification, the analyzer further comprises (a) means for disabling at least a portion of the separation means, such that the ion beam from the source remains undeflected; (b) means located along the path of the undeflected ion beam for sensing the sample ions; and (c) enabling means responsive to the sensing means for automatically re-enabling the separation means when the sample ions reach a predetermined intensity level. (author)

  7. Confirmatory analysis method for zeranol, its metabolites and related mycotoxins in urine by liquid chromatography-negative ion electrospray tandem mass spectrometry

    NARCIS (Netherlands)

    Bennekom, van E.O.; Brouwer, L.; Laurant, E.H.M.; Hooijerink, H.; Nielen, M.W.F.

    2002-01-01

    The determination of the banned anabolic substance zeranol and the metabolites taleranol and zearalanone in bovine urine is complicated by the occurrence of the structurally-related mycotoxin zearalenone and the corresponding - and -zearalenol metabolites which possess similar estrogenic properties.

  8. Spin resonance with trapped ions

    Energy Technology Data Exchange (ETDEWEB)

    Wunderlich, Ch; Balzer, Ch; Hannemann, T; Mintert, F; Neuhauser, W; Reiss, D; Toschek, P E [Institut fuer Laser-Physik, Universitaet Hamburg, Jungiusstrasse 9, 20355 Hamburg (Germany)

    2003-03-14

    A modified ion trap is described where experiments (in particular related to quantum information processing) that usually require optical radiation can be carried out using microwave or radio frequency electromagnetic fields. Instead of applying the usual methods for coherent manipulation of trapped ions, a string of ions in such a modified trap can be treated like a molecule in nuclear magnetic resonance experiments taking advantage of spin-spin coupling. The collection of trapped ions can be viewed as an N-qubit molecule with adjustable spin-spin coupling constants. Given N identically prepared quantum mechanical two-level systems (qubits), the optimal strategy to estimate their quantum state requires collective measurements. Using the ground state hyperfine levels of electrodynamically trapped {sup 171}Yb{sup +}, we have implemented an adaptive algorithm for state estimation involving sequential measurements on arbitrary qubit states.

  9. Spin resonance with trapped ions

    International Nuclear Information System (INIS)

    Wunderlich, Ch; Balzer, Ch; Hannemann, T; Mintert, F; Neuhauser, W; Reiss, D; Toschek, P E

    2003-01-01

    A modified ion trap is described where experiments (in particular related to quantum information processing) that usually require optical radiation can be carried out using microwave or radio frequency electromagnetic fields. Instead of applying the usual methods for coherent manipulation of trapped ions, a string of ions in such a modified trap can be treated like a molecule in nuclear magnetic resonance experiments taking advantage of spin-spin coupling. The collection of trapped ions can be viewed as an N-qubit molecule with adjustable spin-spin coupling constants. Given N identically prepared quantum mechanical two-level systems (qubits), the optimal strategy to estimate their quantum state requires collective measurements. Using the ground state hyperfine levels of electrodynamically trapped 171 Yb + , we have implemented an adaptive algorithm for state estimation involving sequential measurements on arbitrary qubit states

  10. 1+-n+ ECR ION SOURCE DEVELOPMENT TEST STAND

    International Nuclear Information System (INIS)

    Donald P. May

    2006-01-01

    A test stand for the investigation of 1+-n+ charge boosting using an ECR ion sources is currently being assembled at the Texas A and M Cyclotron Institute. The ultimate goal is to relate the charge-boosting of ions of stable species to possible charge-boosting of ions of radioactive species extracted from the diverse, low-charge-state ion sources developed for radioactive ion beams

  11. Recoil ion spectroscopy with heavy ions

    International Nuclear Information System (INIS)

    Beyer, H.F.; Mann, R.

    1984-01-01

    This chapter examines the production of very high charge state ions in single ion-atom collisions. Topics considered include some aspects of highly ionized atoms, experimental approaches, the production of highly charged target ions (monoatomic targets, recoil energy distribution, molecular fragmentation, outer-shell rearrangement, lifetime measurements, a comparison of projectile-, target-, and plasma-ion stripping), and secondary collision experiments (selective electron capture, potential applications). The heavy-ion beams for the described experiments were provided by accelerators such as tandem Van de Graaff facility and the UNILAC

  12. Surface negative ion production in ion sources

    International Nuclear Information System (INIS)

    Belchenko, Y.

    1993-01-01

    Negative ion sources and the mechanisms for negative ion production are reviewed. Several classes of sources with surface origin of negative ions are examined in detail: surface-plasma sources where ion production occurs on the electrode in contact with the plasma, and ''pure surface'' sources where ion production occurs due to conversion or desorption processes. Negative ion production by backscattering, impact desorption, and electron- and photo-stimulated desorption are discussed. The experimental efficiencies of intense surface negative ion production realized on electrodes contacted with hydrogen-cesium or pure hydrogen gas-discharge plasma are compared. Recent modifications of surface-plasma sources developed for accelerator and fusion applications are reviewed in detail

  13. Transport of heavy ions through matter within ion optical systems

    International Nuclear Information System (INIS)

    Schwab, T.

    1991-04-01

    In this thesis for the first time higher-order ion-optical calculations were connected with the whole phase-space changes of the heavy ions in passing through matter. With the developed programs and the newly proposed analytical methods atomic and nuclear interactions of the heavy ions within ion optical systems can be described realistically. The results of this thesis were applied to the conception of the fragment separator (FRS) and to the planning and preparation of experiments at the new GSI accelerator facility. Especially for the description of the ion-optical combination of FRS and the storage ring ESR the developed programs and methods proved to be necessary. A part of the applied theories on the atomic stopping could be confirmed in the framework of this thesis in an experiment with the high-resolving spectrometer SPEC at GANIL. The method of the isotopically pure separation of projectile fragments by means of magnetic analysis and the electronic energy loss could be also experimentally successfully tested at several energies (60-400 MeV/u). Furthermore in this thesis also application-related problems regarding a tumor therapy with heavy ions were solved. A concept for a medical separator (BMS) was developed, which separates light diagnosis beams isotopically purely and beyond improves the energy sharpness by means of an especially shaped (monoenergetic) stopper so that an in-situ range determination is possible with an accuracy of about one millimeter. (orig./HSI) [de

  14. Relation between sedimentation behaviour of DNA-membrane complexes and DNA single- and double-strand breaks after irradiation with gamma-rays, pulse neutrons and 12C ions

    International Nuclear Information System (INIS)

    Erzgraber, G.; Lapidus, I.L.

    1985-01-01

    The experimental data on sedimentation behaviour of DNA-membrane complexes at radiation of the Chinese hamster cells (V79-4) in a wide dose range of 127 Cs γ-rays, pulse neutrons (reactor IBR-2, Laboratory of Neutron Physics, JINR, Dubna) are accelerated 12 C ions (cyclotron U-200, Laboratory of Nuclear Reactions, JINR, Dubna) are presented An assumption on the role of DNA single- and double-strend breaks in changing the sedimentation properties of DNA-membrane complexes has been confirmed by the experiments with radiation of different quality. The possibility of estimating induction and repair of DNA breaks on the basis of dependence of the relative sedimentation velocity of complexes on the irradiation does is discussed

  15. Ion divergence in magnetically insulated diodes

    International Nuclear Information System (INIS)

    Slutz, S.A.; Lemke, R.W.; Pointon, T.D.; Desjarlais, M.P.; Johnson, D.J.; Mehlhorn, T.A.; Filuk, A.; Bailey, J.

    1995-01-01

    Magnetically insulated ion diodes are being developed to drive inertial confinement fusion. Ion beam microdivergence must be reduced to achieve the very high beam intensities required to achieve this goal. Three-dimensional particle-in-cell simulations indicate that instability induced fluctuations can produce significant ion divergence during acceleration. These simulations exhibit a fast growing mode early in time, which has been identified as the diocotron instability. The divergence generated by this mode is modest due to the relatively high frequency (>1GHz). Later, a low-frequency low-phase-velocity instability develops. This instability couples effectively to the ions, since the frequency is approximately the reciprocal of the ion transit time, and can generate unacceptably large ion divergences (>30 mrad). Linear stability theory reveals that this mode requires perturbations parallel to the applied magnetic field and is related to the modified two stream instability. Measurements of ion density fluctuations and energy-momentum correlations have confirmed that instabilities develop in ion diodes and contribute to the ion divergence. In addition, spectroscopic measurements indicate that the ions have a significant transverse temperature very close to the emission surface. Passive lithium fluoride (LiF) anodes have larger transverse beam temperatures than laser irradiated active sources. Calculations of source divergence expected from the roughness of LiF surfaces and the possible removal of this layer is presented

  16. Separation and analysis of phenolic acids from Salvia miltiorrhiza and its related preparations by off-line two-dimensional hydrophilic interaction chromatography×reversed-phase liquid chromatography coupled with ion trap time-of-flight mass spectrometry.

    Science.gov (United States)

    Sun, Wanyang; Tong, Ling; Miao, Jingzhuo; Huang, Jingyi; Li, Dongxiang; Li, Yunfei; Xiao, Hongting; Sun, Henry; Bi, Kaishun

    2016-01-29

    Salvia miltiorrhiza (SM) is one of the most widely used Traditional Chinese Medicine. Active constituents of SM mainly contain hydrophilic phenolic acids (PAs) and lipophilic tanshinones. However, due to the existing of multiple ester bonds and unsaturated bonds in the structures, PAs have numerous chemical conversion products. Many of them are so low-abundant that hard to be separated using conventional methods. In this study, an off-line two-dimensional liquid chromatography (2D-LC) method was developed to separate PAs in SM and its related preparations. In the first dimension, samples were fractionated by hydrophilic interaction chromatography (HILIC) (Acchrom×Amide, 4.6×250mm, 5μm) mainly based on the hydrogen bonding effects. The fractions were then separated on reversed-phase liquid chromatography (RP-LC) (Acquity HSS T3, 2.1×50mm, 1.7μm) according to hydrophobicity. For the selective identification of PAs, diode array detector (DAD) and electrospray ionization tandem ion trap time-of-flight mass spectrometry (ESI-IT-TOF-MS) were employed. Practical and effective peak capacities of all the samples were greater than 2046 and 1130, respectively, with the orthogonalities ranged from 69.7% to 92.8%, which indicated the high efficiency and versatility of this method. By utilizing the data post-processing techniques, including mass defect filter, neutral loss filter and product ion filter, a total of 265 compounds comprising 196 potentially new PAs were tentatively characterized. Twelve kinds of derivatives, mainly including glycosylated compounds, O-alkylated compounds, condensed compounds and hydrolyzed compounds, constituted the novelty of the newly identified PAs. The HILIC×RP-LC/TOF-MS system expanded our understanding on PAs of S. miltiorrhiza and its related preparations, which could also benefit the separation and characterization of polar constituents in complicated herbal extracts. Copyright © 2016. Published by Elsevier B.V.

  17. Physics of ion sputtering

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1984-04-01

    The ejection of atoms by the ion bombardment of solids is discussed in terms of linear collision cascade theory. A simple argument describes the energies of the ejecta, but elaborate models are required to obtain accurate sputtering yields and related quantities. These include transport theoretical models based on linearized Boltzmann equations, computer simulation models based on the binary collision approximation, and classical many-body dynamical models. The role of each kind of model is discussed. Several aspects of sputtering are illustrated by results from the simulation code MARLOWE. 20 references, 6 figures

  18. Compact ion accelerator source

    Science.gov (United States)

    Schenkel, Thomas; Persaud, Arun; Kapadia, Rehan; Javey, Ali

    2014-04-29

    An ion source includes a conductive substrate, the substrate including a plurality of conductive nanostructures with free-standing tips formed on the substrate. A conductive catalytic coating is formed on the nanostructures and substrate for dissociation of a molecular species into an atomic species, the molecular species being brought in contact with the catalytic coating. A target electrode placed apart from the substrate, the target electrode being biased relative to the substrate with a first bias voltage to ionize the atomic species in proximity to the free-standing tips and attract the ionized atomic species from the substrate in the direction of the target electrode.

  19. Cellular radiobiology of heavy-ion beams

    International Nuclear Information System (INIS)

    Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.; Roots, R.J.; Yang, T.C.

    1981-01-01

    Progress is reported in the following areas of this research program: relative biological effectiveness and oxygen enhancement ratio of silicon ion beams; heavy ion effects on the cell cycle; the potentiation effect (2 doses of high LET heavy-ion radiations separated by 2 to 3 hours); potentially lethal damage in actively growing cells and plateau growth cells; radiation induced macromolecular lesions and cellular radiation chemistry; lethal effects of dual radiation; and the development of a biophysical repair/misrepair model

  20. Collisions of low-energy multicharged ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.; Crandall, D.H.

    1981-01-01

    Experimental measurements of cross sections for collisions of multiply charged ions with atoms at the lowest attainable collision energies are reported. Emphasis is on electron capture from hydrogen atoms by multiply charged ions at energies below 1 keV/amu. The principal effort is the development of a merged-ion-atom-beams apparatus for studies down to 1 eV/amu relative energy

  1. Apparatus for neutralization of accelerated ions

    International Nuclear Information System (INIS)

    Fink, J.H.; Frank, A.M.

    1979-01-01

    Apparatus is described for neutralization of a beam of accelerated ions, such as hydrogen negative ions (H - ), using relatively efficient strip diode lasers which emit monochromatically at an appropriate wavelength (lambda = 8000 A for H - ions) to strip the excess electrons by photodetachment. A cavity, formed by two or more reflectors spaced apart, causes the laser beams to undergo multiple reflections within the cavity, thus increasing the efficiency and reducing the illumination required to obtain an acceptable percentage (approx. 85%) of neutralization

  2. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

  3. Molecular ions in comet tails

    International Nuclear Information System (INIS)

    Wyckoff, S.; Wehinger, P.A.

    1976-01-01

    Band intensities of the molecular ions CH + , CO + , N 2 + , and H 2 O + have been determined on an absolute scale from tail spectra of comet Kohoutek (1973f) and comet Bradfield (1974b). Photoionization and photodissociation rates have been computed for CH, CO, and N 2 . Also emission rate excitation g-factors for (1) photoionization plus excitation and (2) resonance fluorescence have been computed for the observed ions. It is shown that resonance fluorescence is the dominant excitation mechanism for observed comet tail ions at rapprox. =1 AU. Band system luminosities and molecular ion abundances within a projected nuclear distance rho 4 km have been determined for CH + , CO + , N 2 + , and H 2 O + in comet Kohoutek, and for H 2 O + in comet Bradfield. Estimates are also given for column densities of all observed ions at rhoapprox. =10 4 km on the tailward side of the coma. The observed H 2 O + column densities were found to be roughly the same in comet Kohoutek and comet Bradfield et equal heliocentric distances, while CO + was found to be approximately 100 times more abundant than H 2 O + , N 2 + , and CH + at rhoapprox. =10 4 km in comet Kohoutek. Finally, the relative abundances of the observed ions and of the presumed parent neutral species are briefly discussed

  4. Periodic organosilica hollow nanospheres as anode materials for lithium ion rechargeable batteries

    Science.gov (United States)

    Sasidharan, Manickam; Nakashima, Kenichi; Gunawardhana, Nanda; Yokoi, Toshiyuki; Ito, Masanori; Inoue, Masamichi; Yusa, Shin-Ichi; Yoshio, Masaki; Tatsumi, Takashi

    2011-11-01

    Polymeric micelles with core-shell-corona architecture have been found to be the efficient colloidal templates for synthesis of periodic organosilica hollow nanospheres over a broad pH range from acidic to alkaline media. In alkaline medium, poly (styrene-b-[3-(methacryloylamino)propyl] trimethylammonium chloride-b-ethylene oxide) (PS-PMAPTAC-PEO) micelles yield benzene-silica hollow nanospheres with molecular scale periodicity of benzene groups in the shell domain of hollow particles. Whereas, an acidic medium (pH 4) produces diverse hollow particles with benzene, ethylene, and a mixture of ethylene and dipropyldisulfide bridging functionalities using poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-PVP-PEO) micelles. These hollow particles were thoroughly characterized by powder X-ray diffraction (XRD), dynamic light scattering (DLS), thermogravimetric analysis (TG/DTA), Fourier transformation infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), magic angle spinning-nuclear magnetic resonance (29Si MAS NMR and 13CP-MAS NMR), Raman spectroscopy, and nitrogen adsorption/desorption analyses. The benzene-silica hollow nanospheres with molecular scale periodicity in the shell domain exhibit higher cycling performance of up to 300 cycles in lithium ion rechargeable batteries compared with micron-sized dense benzene-silica particles.Polymeric micelles with core-shell-corona architecture have been found to be the efficient colloidal templates for synthesis of periodic organosilica hollow nanospheres over a broad pH range from acidic to alkaline media. In alkaline medium, poly (styrene-b-[3-(methacryloylamino)propyl] trimethylammonium chloride-b-ethylene oxide) (PS-PMAPTAC-PEO) micelles yield benzene-silica hollow nanospheres with molecular scale periodicity of benzene groups in the shell domain of hollow particles. Whereas, an acidic medium (pH 4) produces diverse hollow particles with benzene, ethylene, and a mixture of ethylene and

  5. Laser ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Bykovskij, Yu

    1979-02-01

    The characteristics a laser source of multiply-ionized ions are described with regard to the interaction of laser radiation and matter, ion energy spectrum, angular ion distribution. The amount of multiple-ionization ions is evaluated. Out of laser source applications a laser injector of multiple-ionization ions and nuclei, laser mass spectrometry, laser X-ray microradiography, and a laser neutron generators are described.

  6. Results of heavy ion radiotherapy

    International Nuclear Information System (INIS)

    Castro, J.R.

    1994-04-01

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists

  7. Ion Beam Propulsion Study

    Science.gov (United States)

    2008-01-01

    The Ion Beam Propulsion Study was a joint high-level study between the Applied Physics Laboratory operated by NASA and ASRC Aerospace at Kennedy Space Center, Florida, and Berkeley Scientific, Berkeley, California. The results were promising and suggested that work should continue if future funding becomes available. The application of ion thrusters for spacecraft propulsion is limited to quite modest ion sources with similarly modest ion beam parameters because of the mass penalty associated with the ion source and its power supply system. Also, the ion source technology has not been able to provide very high-power ion beams. Small ion beam propulsion systems were used with considerable success. Ion propulsion systems brought into practice use an onboard ion source to form an energetic ion beam, typically Xe+ ions, as the propellant. Such systems were used for steering and correction of telecommunication satellites and as the main thruster for the Deep Space 1 demonstration mission. In recent years, "giant" ion sources were developed for the controlled-fusion research effort worldwide, with beam parameters many orders of magnitude greater than the tiny ones of conventional space thruster application. The advent of such huge ion beam sources and the need for advanced propulsion systems for exploration of the solar system suggest a fresh look at ion beam propulsion, now with the giant fusion sources in mind.

  8. Negative ion sources

    International Nuclear Information System (INIS)

    Ishikawa, Junzo; Takagi, Toshinori

    1983-01-01

    Negative ion sources have been originally developed at the request of tandem electrostatic accelerators, and hundreds of nA to several μA negative ion current has been obtained so far for various elements. Recently, the development of large current hydrogen negative ion sources has been demanded from the standpoint of the heating by neutral particle beam injection in nuclear fusion reactors. On the other hand, the physical properties of negative ions are interesting in the thin film formation using ions. Anyway, it is the present status that the mechanism of negative ion action has not been so fully investigated as positive ions because the history of negative ion sources is short. In this report, the many mechanisms about the generation of negative ions proposed so far are described about negative ion generating mechanism, negative ion source plasma, and negative ion generation on metal surfaces. As a result, negative ion sources are roughly divided into two schemes, plasma extraction and secondary ion extraction, and the former is further classified into the PIG ion source and its variation and Duoplasmatron and its variation; while the latter into reflecting and sputtering types. In the second half of the report, the practical negative ion sources of each scheme are described. If the mechanism of negative ion generation will be investigated more in detail and the development will be continued under the unified know-how as negative ion sources in future, the development of negative ion sources with which large current can be obtained for any element is expected. (Wakatsuki, Y.)

  9. Ion sources for heavy ion fusion

    International Nuclear Information System (INIS)

    Yu, S.S.; Eylon, S.; Chupp, W.

    1995-09-01

    The development of ion sources for heavy ion fusion will be reported with particular emphasis on a recently built 2 MV injector. The new injector is based on an electrostatic quadrupole configuration, and has produced pulsed K + ions of 950 mA peak from a 6.7 inch curved alumino silicate source. The ion beam has reached 2.3 MV with an energy flatness of ±0.2% over 1 micros. The measured normalized edge emittance of less than 1 π mm-mr is close to the source temperature limit. The design, construction, performance, and comparisons with three-dimensional particle-in-cell simulations will be described

  10. Electron-impact excitation of molecular ions

    International Nuclear Information System (INIS)

    Neufeld, D.A.; Dalgarno, A.

    1989-01-01

    A simple expression is derived that relates the rate coefficient for dipole-allowed electron-impact excitation of a molecular ion in the Coulomb-Born approximation to the Einstein A coefficient for the corresponding radiative decay. Results are given for several molecular ions of astrophysical interest. A general analytic expression is obtained for the equilibrium rotational level populations in the ground vibrational state of any molecular ion excited by collisions with electrons. The expression depends only upon the electron temperature, the electron density, and the rotational constant of the molecular ion. A similar expression is obtained for neutral polar molecules

  11. New ways of polymeric ion track characterization

    International Nuclear Information System (INIS)

    Fink, D.; Mueller, M.; Ghosh, S.; Dwivedi, K.K.; Vacik, J.; Hnatowicz, V.; Cervena, J.; Kobayashi, Y.; Hirata, K.

    1999-01-01

    New ways have been applied for characterization of ion tracks in polymers in the last few years, which are essentially related to depth profile determinations of ions, molecules, or positrons penetrating into these tracks. In combination with tomography, the first three-dimensional results have been obtained. Extensive diffusion simulations accompanying the measurements have enabled us to obtain a better understanding of the transport processes going on in ion tracks. This paper gives an overview about the range of new possibilities accessible by these techniques, and summarizes the presently obtained understanding of ion tracks in polymers

  12. Heavy Ion Fusion Accelerator Research (HIFAR)

    International Nuclear Information System (INIS)

    1991-04-01

    This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C s + sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac

  13. Ion acceleration in the plasma source sheath

    International Nuclear Information System (INIS)

    Birdsall, C.K.

    1986-01-01

    This note is a calculation of the potential drop for a planar plasma source, across the source sheath, into a uniform plasma region defined by vector E = 0 and/or perhaps ∂ 2 PHI/∂ x 2 = 0. The calculation complements that of Bohm who obtained the potential drop at the other end of a plasma, at a planar collector sheath. The result is a relation between the source ion flux and the source sheath potential drop and the accompanying ion acceleration. This planar source sheath ion acceleration mechanism (or that from a distributed source) can provide the pre-collector-sheath ion acceleration as found necessary by Bohm. 3 refs

  14. Li-ion batteries: Phase transition

    International Nuclear Information System (INIS)

    Hou Peiyu; Zhang Yantao; Zhang Lianqi; Chu Geng; Gao Jian

    2016-01-01

    Progress in the research on phase transitions during Li + extraction/insertion processes in typical battery materials is summarized as examples to illustrate the significance of understanding phase transition phenomena in Li-ion batteries. Physical phenomena such as phase transitions (and resultant phase diagrams) are often observed in Li-ion battery research and already play an important role in promoting Li-ion battery technology. For example, the phase transitions during Li + insertion/extraction are highly relevant to the thermodynamics and kinetics of Li-ion batteries, and even physical characteristics such as specific energy, power density, volume variation, and safety-related properties. (topical review)

  15. Loss of metal ions, disulfide reduction and mutations related to familial ALS promote formation of amyloid-like aggregates from superoxide dismutase.

    Directory of Open Access Journals (Sweden)

    Zeynep A Oztug Durer

    Full Text Available Mutations in the gene encoding Cu-Zn superoxide dismutase (SOD1 are one of the causes of familial amyotrophic lateral sclerosis (FALS. Fibrillar inclusions containing SOD1 and SOD1 inclusions that bind the amyloid-specific dye thioflavin S have been found in neurons of transgenic mice expressing mutant SOD1. Therefore, the formation of amyloid fibrils from human SOD1 was investigated. When agitated at acidic pH in the presence of low concentrations of guanidine or acetonitrile, metalated SOD1 formed fibrillar material which bound both thioflavin T and Congo red and had circular dichroism and infrared spectra characteristic of amyloid. While metalated SOD1 did not form amyloid-like aggregates at neutral pH, either removing metals from SOD1 with its intramolecular disulfide bond intact or reducing the intramolecular disulfide bond of metalated SOD1 was sufficient to promote formation of these aggregates. SOD1 formed amyloid-like aggregates both with and without intermolecular disulfide bonds, depending on the incubation conditions, and a mutant SOD1 lacking free sulfhydryl groups (AS-SOD1 formed amyloid-like aggregates at neutral pH under reducing conditions. ALS mutations enhanced the ability of disulfide-reduced SOD1 to form amyloid-like aggregates, and apo-AS-SOD1 formed amyloid-like aggregates at pH 7 only when an ALS mutation was also present. These results indicate that some mutations related to ALS promote formation of amyloid-like aggregates by facilitating the loss of metals and/or by making the intramolecular disulfide bond more susceptible to reduction, thus allowing the conversion of SOD1 to a form that aggregates to form resembling amyloid. Furthermore, the occurrence of amyloid-like aggregates per se does not depend on forming intermolecular disulfide bonds, and multiple forms of such aggregates can be produced from SOD1.

  16. Electron Beam Ion Sources

    CERN Document Server

    Zschornacka, G.; Thorn, A.

    2013-12-16

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviolet, visible light) from highly charged ions. This chapter gives an overview of EBIS physics, the principle of operation, and the known technical solutions. Using examples, the performance of EBISs as well as their applications in various fields of basic research, technology and medicine are discussed.

  17. Molecular ions, Rydberg spectroscopy and dynamics

    International Nuclear Information System (INIS)

    Jungen, Ch.

    2015-01-01

    Ion spectroscopy, Rydberg spectroscopy and molecular dynamics are closely related subjects. Multichannel quantum defect theory is a theoretical approach which draws on this close relationship and thereby becomes a powerful tool for the study of systems consisting of a positively charged molecular ion core interacting with an electron which may be loosely bound or freely scattering

  18. Molecular ions, Rydberg spectroscopy and dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Jungen, Ch. [Laboratoire Aimé Cotton, Université de Paris-Sud, 91405 Orsay (France)

    2015-01-22

    Ion spectroscopy, Rydberg spectroscopy and molecular dynamics are closely related subjects. Multichannel quantum defect theory is a theoretical approach which draws on this close relationship and thereby becomes a powerful tool for the study of systems consisting of a positively charged molecular ion core interacting with an electron which may be loosely bound or freely scattering.

  19. Negative electrodes for Na-ion batteries.

    Science.gov (United States)

    Dahbi, Mouad; Yabuuchi, Naoaki; Kubota, Kei; Tokiwa, Kazuyasu; Komaba, Shinichi

    2014-08-07

    Research interest in Na-ion batteries has increased rapidly because of the environmental friendliness of sodium compared to lithium. Throughout this Perspective paper, we report and review recent scientific advances in the field of negative electrode materials used for Na-ion batteries. This paper sheds light on negative electrode materials for Na-ion batteries: carbonaceous materials, oxides/phosphates (as sodium insertion materials), sodium alloy/compounds and so on. These electrode materials have different reaction mechanisms for electrochemical sodiation/desodiation processes. Moreover, not only sodiation-active materials but also binders, current collectors, electrolytes and electrode/electrolyte interphase and its stabilization are essential for long cycle life Na-ion batteries. This paper also addresses the prospect of Na-ion batteries as low-cost and long-life batteries with relatively high-energy density as their potential competitive edge over the commercialized Li-ion batteries.

  20. High-energy ion implantation of materials

    International Nuclear Information System (INIS)

    Williams, J.M.

    1991-11-01

    High-energy ion implantation is an extremely flexible type of surface treatment technique, in that it offers the possibility of treating almost any type of target material or product with ions of almost any chemical species, or combinations of chemical species. In addition, ion implantations can be combined with variations in temperature during or after ion implantation. As a result, the possibility of approaching a wide variety of surface-related materials science problems exists with ion implantation. This paper will outline factors pertinent to application of high-energy ion implantation to surface engineering problems. This factors include fundamental advantages and limitations, economic considerations, present and future equipment, and aspects of materials science

  1. Ions and light

    CERN Document Server

    Bowers, Michael T

    2013-01-01

    Gas Phase Ion Chemistry, Volume 3: Ions and Light discusses how ions are formed by electron impact, ion-molecule reactions, or electrical discharge. This book discusses the use of light emitted by excited molecules to characterize either the chemistry that formed the excited ion, the structure of the excited ion, or both.Organized into 10 chapters, this volume begins with an overview of the extension of the classical flowing afterglow technique to include infrared and chemiluminescence and laser-induced fluorescence detection. This text then examines the experiments involving molecules that ar

  2. Recent advances in vacuum arc ion sources

    International Nuclear Information System (INIS)

    Brown, I.G.; Anders, A.; Anders, S.; Dickinson, M.R.; MacGill, R.A.; Oks, E.M.

    1995-07-01

    Intense beams of metal ions can be formed from a vacuum arc ion source. Broadbeam extraction is convenient, and the time-averaged ion beam current delivered downstream can readily be in the tens of milliamperes range. The vacuum arc ion source has for these reasons found good application for metallurgical surface modification--it provides relatively simple and inexpensive access to high dose metal ion implantation. Several important source developments have been demonstrated recently, including very broad beam operation, macroparticle removal, charge state enhancement, and formation of gaseous beams. The authors have made a very broad beam source embodiment with beam formation electrodes 50 cm in diameter, producing a beam of width ∼35 cm for a nominal beam area of ∼1,000 cm 2 , and a pulsed Ti beam current of about 7 A was formed at a mean ion energy of ∼100 keV. Separately, they've developed high efficiency macroparticle-removing magnetic filters and incorporated such a filter into a vacuum arc ion source so as to form macroparticle-free ion beams. Jointly with researchers at the High Current Electronics Institute at Tomsk, Russia, and the Gesellschaft fuer Schwerionenforschung at Darmstadt, Germany, they've developed a compact technique for increasing the charge states of ions produced in the vacuum arc plasma and thus providing a simple means of increasing the ion energy at fixed extractor voltage. Finally, operation with mixed metal and gaseous ion species has been demonstrated. Here, they briefly review the operation of vacuum marc ion sources and the typical beam and implantation parameters that can be obtained, and describe these source advances and their bearing on metal ion implantation applications

  3. Transport of intense ion beams

    International Nuclear Information System (INIS)

    Lambertson, G.; Laslett, L.J.; Smith, L.

    1977-01-01

    The possibility of using intense bursts of heavy ions to initiate an inertially confined fusion reaction has stimulated interest in the transport of intense unneutralized heavy ion beams by quadrupole or solenoid systems. This problem was examined in some detail, using numerical integration of the coupled envelope equations for the quadrupole case. The general relations which emerge are used to develop examples of high energy transport systems and as a basis for discussing the limitations imposed by a transport system on achievable intensities for initial acceleration

  4. Changes in surface properties caused by ion implantation

    International Nuclear Information System (INIS)

    Iwaki, Masaya

    1987-01-01

    This report outlines various aspects of ion implantation. Major features of ion implantation are described first, focusing on the structure of ion implantation equipment and some experimental results of ion implantation into semiconductors. Distribution of components in ion-implantated layers is then discussed. The two major features of ion implantation in relation to the distribution of implanted ions are: (1) high controllability of addition of ions to a surface layer and (2) formation of a large number of lattice defects in a short period of time. Application of ion implantation to metallic materials is expected to permit the following: (1) formation of a semi-stable alloy surface layer by metallic ion implantation, (2) formation of a semi-stable ceramic surface layer or buried layer by non-metallic ion implantation, and (3) formation of a buried layer by combined implementation of a different metallic ion and non-metallic ion. Ion implantation in carbon materials, polymers and ceramics is discussed next. The last part of the report is dedicated to macroscopic properties of an ion-implanted layer, centering on surface modification, formation of a conductive surface layer, and tribology. (Nogami, K.) 60 refs

  5. Materials Science with Ion Beams

    CERN Document Server

    Bernas, Harry

    2010-01-01

    This book introduces materials scientists and designers, physicists and chemists to the properties of materials that can be modified by ion irradiation or implantation. These techniques can help design new materials or to test modified properties; novel applications already show that ion-beam techniques are complementary to others, yielding previously unattainable properties. Also, ion-beam interactions modify materials at the nanoscale, avoiding the often detrimental results of lithographic or chemical techniques. Here, the effects are related to better-known quasi-equilibrium thermodynamics, and the consequences to materials are discussed with concepts that are familiar to materials science. Examples addressed concern semiconductor physics, crystal and nanocluster growth, optics, magnetism, and applications to geology and biology.

  6. Negative-ion states

    International Nuclear Information System (INIS)

    Compton, R.N.

    1982-01-01

    In this brief review, we discuss some of the properties of atomic and molecular negative ions and their excited states. Experiments involving photon reactions with negative ions and polar dissociation are summarized. 116 references, 14 figures

  7. Quadrupole Ion Traps

    Indian Academy of Sciences (India)

    to do precision spectroscopic measurements on these ions. ... Bonn, investigated the non-magnetic quadrupole mass filter, .... the details of which will be discussed in the subse- ... the radial plane the ion undergoes a circular motion with the.

  8. Negative ion detachment processes

    International Nuclear Information System (INIS)

    Champion, R.L.; Doverspike, L.D.

    1990-10-01

    This paper discusses the following topics: H - and D - collisions with atomic hydrogen; collisional decomposition of SF 6 - ; two-electron loss processes in negative ion collisions; associative electron detachment; and negative ion desorption from surfaces

  9. Ion sources in AMS

    International Nuclear Information System (INIS)

    Iyer, Indira S.

    1997-01-01

    Accelerator Mass Spectrometry (AMS) entails the sputtering of various samples in an ion source followed by high precision mass analysis of the sputtered ion species in a Tandem Electrostatic Accelerator. A brief account is given

  10. Single Cathode Ion Thruster

    Data.gov (United States)

    National Aeronautics and Space Administration — Objective is to design an electrostatic ion thruster that is more efficient, simpler, and lower cost than the current gridded ion thruster. Initial objective is to...

  11. Applications of decelerated ions

    International Nuclear Information System (INIS)

    Johnson, B.M.

    1985-03-01

    Many facilities whose sole purpose had been to accelerate ion beams are now becoming decelerators as well. The development and current status of accel-decel operations is reviewed here. Applications of decelerated ions in atomic physics experiments are discussed

  12. Fundamentals of ion exchange

    International Nuclear Information System (INIS)

    Townsend, R.P.

    1993-01-01

    In this paper the fundamentals of ion exchange mechanisms and their thermodynamics are described. A range of ion exchange materials is considered and problems of communication and technology transfer between scientists working in the field are discussed. (UK)

  13. Ion acceleration in modulated electron beams

    International Nuclear Information System (INIS)

    Bonch-Osmolovskij, A.G.; Dolya, S.N.

    1977-01-01

    A method of ion acceleration in modulated electron beams is considered. Electron density and energy of their rotational motion are relatively low. However the effective ion-accelerating field is not less than 10 MeV/m. The electron and ion numbers in an individual bunch are also relatively small, although the number of produced bunches per time unit is great. Some aspects of realization of the method are considered. Possible parameters of the accelerator are given. At 50 keV electron energy and 1 kA beam current a modulation is realized at a wave length of 30 cm. The ion-accelerating field is 12 MeV/m. The bunch number is 2x10 3 in one pulse at a gun pulse duration of 2 μs. With a pulse repetition frequency of 10 2 Hz the number of accelerated ions can reach 10 13 -10 14 per second

  14. Control of colliding ion beams

    International Nuclear Information System (INIS)

    Salisbury, W.W.

    1985-01-01

    This invention relates to a method and system for enhancing the power-producing capability of a nuclear fusion reactor, and more specifically to methods and structure for enhancing the ion density in a directed particle fusion reactor. In accordance with the invention, oppositely directed ion beams constrained to helical paths pass through an annular reaction zone. The object is to produce fusion reactions due to collisions between the ion beams. The reaction zone is an annulus as between an inner-cylindrical electrode and an outer-cylindrical coaxial electrode. The beams are enhanced in ion density at spaced points along the paths by providing spline structures protruding from the walls of the electrodes into the reaction zone. This structure causes variations in the electric field along the paths followed by the ion beams. Such fields cause the beams to be successively more and less concentrated as the beams traverse the reaction zone. Points of high concentration are the points at which fusion-producing collisions are most likely to take place

  15. Alternative crystal field parameters for rare-earth ions obtained from various techniques: IV. Comparative analysis of crystal field parameters obtained from inelastic neutron scattering and related studies of RE ions (RE = Er{sup 3+}, Ho{sup 3+}, Nd{sup 3+}, Pr{sup 3+}) in REBa{sub 2}Cu{sub 3}O{sub 7-{delta}} high-T{sub c} superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Rudowicz, Czeslaw, E-mail: crudowicz@zut.edu.pl [Modeling in Spectroscopy Group, Institute of Physics, Faculty of Mechanical Engineering and Mechatronics, West Pomeranian University of Technology, Szczecin, al. Piastow 48, 70-311 Szczecin (Poland); Lewandowska, Monika [Modeling in Spectroscopy Group, Institute of Physics, Faculty of Mechanical Engineering and Mechatronics, West Pomeranian University of Technology, Szczecin, al. Piastow 48, 70-311 Szczecin (Poland)

    2012-11-05

    Highlights: Black-Right-Pointing-Pointer Orthorhombic crystal field parameters (CFPs) for RE3{sup +} in REBa{sub 2}Cu{sub 3}O{sub 7-{delta}} studied. Black-Right-Pointing-Pointer Comparative analysis of CFP sets for Er{sup 3+}, Ho{sup 3+}, Nd{sup 3+}, and Pr{sup 3+} ions performed. Black-Right-Pointing-Pointer Aspects related to CFP standardization considered. Black-Right-Pointing-Pointer Several problems identified due to comparative CFP analysis clarified. Black-Right-Pointing-Pointer Correct comparison of different CFP sets must be based on standardization. - Abstract: This is fourth paper in a series devoted to reanalysis of the non-standard and standard crystal-field (CF) parameter (CFP) sets obtained from various experimental techniques and theoretical models for trivalent rare-earth (RE) ions in high-critical-temperature (high-T{sub c}) superconductors and related systems. In this paper the experimental orthorhombic CFPs, obtained mostly by inelastic neutron scattering techniques and to a lesser extent by magnetic susceptibility and specific heat measurements as well as the respective theoretical CFPs for Er{sup 3+}, Ho{sup 3+}, Nd{sup 3+}, and Pr{sup 3+} ions in REBa{sub 2}Cu{sub 3}O{sub 7-{delta}} compounds, are considered. Several problems identified due to the comparative CFP analysis: (i) confusing notations used for operators and CFPs, (ii) different scaling factors and units used for CFPs, and (iii) lack of clear definitions of the axis systems used to express CFPs, were clarified. For each ion studied the available experimental and theoretical CFP sets are analyzed, standardized, and presented in a unified way. The large number of CFP sets prevents calculation of the five additional alternative sets for each originally reported CFP set. Instead, the alternative CFP sets are determined using the package CST for an average set calculated for selected compatible sets for each ion. These alternative CFP sets may be utilized in the multiple correlated

  16. Gas phase ion chemistry

    CERN Document Server

    Bowers, Michael T

    1979-01-01

    Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation

  17. Ion mobility spectrometry

    CERN Document Server

    Eiceman, GA

    2005-01-01

    Key Developments for Faster, More Precise Detection Capabilities Driven by the demand for the rapid and advanced detection of explosives, chemical and biological warfare agents, and narcotics, ion mobility spectrometry (IMS) undergone significant refinements in technology, computational capabilities, and understanding of the principles of gas phase ion chemistry and mobility. Beginning with a thorough discussion of the fundamental theories and physics of ion mobility, Ion Mobility Spectrometry, Second Edition describes the recent advances in instrumentation and newly

  18. Intense ion beam generator

    International Nuclear Information System (INIS)

    Humphries, S. Jr.; Sudan, R.N.

    1977-01-01

    Methods and apparatus for producing intense megavolt ion beams are disclosed. In one embodiment, a reflex triode-type pulsed ion accelerator is described which produces ion pulses of more than 5 kiloamperes current with a peak energy of 3 MeV. In other embodiments, the device is constructed so as to focus the beam of ions for high concentration and ease of extraction, and magnetic insulation is provided to increase the efficiency of operation

  19. Ion smoke detector

    International Nuclear Information System (INIS)

    Basset, Georges.

    1976-01-01

    This invention covers an ion smoke detector in which the capacity that the smoke will cross, in the event of an accident, is irradiated by a very low energy radioactive source. The gas in the containment is thus partially ionised. Smoke in this containment reduces the mobility of the ions, thereby increasing the impedance of the measuring chamber. A leak tight reference chamber that therefore receives no smoke is added to the measuring chamber. This chamber is filled with the same gas as that present in the measuring chamber and undergoes the same irradiation. It is of course subjected to the same conditions of temperature, atmospheric pressure and hygrometry as the measuring chamber. This makes it possible to break free from the fluctuations of the impedance of the chamber which would seem to be due to these interferences. One only radioactive source irradiates the measuring chamber and the reference chamber. The measuring chamber is in the shape of a cylinder open at one end and the reference chamber is annular and encompasses the measuring chamber. Provision is made for detecting an increase in the potential across the terminals of the measuring chamber in relation to the reference chamber, which is characteristic of the presence of smoke and other provisions separate from the former for dectecting a reduction in potential between the electrodes of the first ionisation chamber, which is characteristic of a change in the detector [fr

  20. Ion sources for accelerators

    International Nuclear Information System (INIS)

    Alton, G.D.

    1974-01-01

    A limited review of low charge sate positive and negative ion sources suitable for accelerator use is given. A brief discussion is also given of the concepts underlying the formation and extraction of ion beams. Particular emphasis is placed on the technology of ion sources which use solid elemental or molecular compounds to produce vapor for the ionization process

  1. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  2. Nanostructures by ion beams

    Science.gov (United States)

    Schmidt, B.

    Ion beam techniques, including conventional broad beam ion implantation, ion beam synthesis and ion irradiation of thin layers, as well as local ion implantation with fine-focused ion beams have been applied in different fields of micro- and nanotechnology. The ion beam synthesis of nanoparticles in high-dose ion-implanted solids is explained as phase separation of nanostructures from a super-saturated solid state through precipitation and Ostwald ripening during subsequent thermal treatment of the ion-implanted samples. A special topic will be addressed to self-organization processes of nanoparticles during ion irradiation of flat and curved solid-state interfaces. As an example of silicon nanocrystal application, the fabrication of silicon nanocrystal non-volatile memories will be described. Finally, the fabrication possibilities of nanostructures, such as nanowires and chains of nanoparticles (e.g. CoSi2), by ion beam synthesis using a focused Co+ ion beam will be demonstrated and possible applications will be mentioned.

  3. Determination of gas phase protein ion densities via ion mobility analysis with charge reduction.

    Science.gov (United States)

    Maisser, Anne; Premnath, Vinay; Ghosh, Abhimanyu; Nguyen, Tuan Anh; Attoui, Michel; Hogan, Christopher J

    2011-12-28

    We use a charge reduction electrospray (ESI) source and subsequent ion mobility analysis with a differential mobility analyzer (DMA, with detection via both a Faraday cage electrometer and a condensation particle counter) to infer the densities of single and multiprotein ions of cytochrome C, lysozyme, myoglobin, ovalbumin, and bovine serum albumin produced from non-denaturing (20 mM aqueous ammonium acetate) and denaturing (1 : 49.5 : 49.5, formic acid : methanol : water) ESI. Charge reduction is achieved through use of a Po-210 radioactive source, which generates roughly equal concentrations of positive and negative ions. Ions produced by the source collide with and reduce the charge on ESI generated drops, preventing Coulombic fissions, and unlike typical protein ESI, leading to gas-phase protein ions with +1 to +3 excess charges. Therefore, charge reduction serves to effectively mitigate any role that Coulombic stretching may play on the structure of the gas phase ions. Density inference is made via determination of the mobility diameter, and correspondingly the spherical equivalent protein volume. Through this approach it is found that for both non-denaturing and denaturing ESI-generated ions, gas-phase protein ions are relatively compact, with average densities of 0.97 g cm(-3) and 0.86 g cm(-3), respectively. Ions from non-denaturing ESI are found to be slightly more compact than predicted from the protein crystal structures, suggesting that low charge state protein ions in the gas phase are slightly denser than their solution conformations. While a slight difference is detected between the ions produced with non-denaturing and denaturing ESI, the denatured ions are found to be much more dense than those examined previously by drift tube mobility analysis, in which charge reduction was not employed. This indicates that Coulombic stretching is typically what leads to non-compact ions in the gas-phase, and suggests that for gas phase

  4. Secondary ions produced from condensed rare gas targets under highly charged MeV/amu heavy ion bombardment

    International Nuclear Information System (INIS)

    Tawara, H.; Tonuma, T.; Kumagai, H.; Matsuo, T.

    1994-01-01

    Secondary ions produced from condensed rare gas targets are observed under MeV/amu, highly charged, heavy ion impact. The intensities of the observed cluster ions decrease smoothly as the cluster sizes become large but show some discontinuities at particular sizes of cluster ions. This seems to be closely related to the stabilities of cluster ion structures. It is also noted that very few doubly charged or practically no triply/higher charged ions have been observed, in sharp contrast to that of some condensed molecular targets. (orig.)

  5. Enhanced ion acoustic fluctuations and ion outflows

    Directory of Open Access Journals (Sweden)

    F. R. E. Forme

    1999-02-01

    Full Text Available A number of observations showing enhanced ion acoustic echoes observed by means of incoherent scatter radars have been reported in the literature. The received power is extremely enhanced by up to 1 or 2 orders of magnitude above usual values, and it is mostly contained in one of the two ion acoustic lines. This spectral asymmetry and the intensity of the received signal cannot be resolved by the standard analysis procedure and often causes its failure. As a result, and in spite of a very clear spectral signature, the analysis is unable to fit the plasma parameters inside the regions of ion acoustic turbulence. We present European Incoherent Scatter radar (EISCAT observations of large ion outflows associated with the simultaneous occurrence of enhanced ion acoustic echoes. The ion fluxes can reach 1014 m-2 s-1 at 800 km altitude. From the very clear spectral signatures of these echoes, a method is presented to extract estimates of the electron temperature and the ion drift within the turbulent regions. It is shown that the electron gas is strongly heated up to 11 000 K. Also electron temperature gradients of about 0.02 K/m exist. Finally, the estimates of the electron temperature and of the ion drift are used to study the possible implications for the plasma transport inside turbulent regions. It is shown that strong electron temperature gradients cause enhancement of the ambipolar electric field and can account for the observed ion outflows.Key words. Ionosphere (auroral ionosphere; ionosphere · magnetosphere interactions; plasma waves and instabilities.

  6. Nuclear targets, recoil ion catchers and reaction chambers

    NARCIS (Netherlands)

    Dionisio, JS; Vieu, C; Schuck, C; Collatz, R; Meunier, R; Ledu, D; Folger, H; Lafoux, A; Lagrange, JM; Pautrat, M; Waast, B; Phillips, WR; Blunt, D; Durell, JL; Varley, BJ; Dagnall, PG; Dorning, SJ; JONES, MA; Smith, AG; Bacelar, JCS; Rzaca-Urban, T; Amzal, N; Meliani, Z; Vanhorenbeeck, J; Passoja, A; Urban, W

    1998-01-01

    The main features of nuclear targets, recoil ion catchers and reaction chambers used in nuclear spectroscopic investigations involving in-beam multi-e-gamma spectrometers are discussed. The relative importance of the F-ray background due to the accelerated ion-target and the recoil-ion-target

  7. Heavy ion induced mutation in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy ions, He, C, Ar and Ne were irradiated to the seeds of Arabidopsis thaliana for inducing the new mutants. In the irradiated generation (M{sub 1}), germination and survival rate were observed to estimate the relative biological effectiveness in relation to the LET including the inactivation cross section. Mutation frequencies were compared by using three kinds of genetic loci after irradiation with C ions and electrons. Several interesting new mutants were selected in the selfed progenies of heavy ion irradiated seeds. (author)

  8. Neutron generator tube ion source control

    International Nuclear Information System (INIS)

    Bridges, J.R.

    1982-01-01

    A system is claimed for controlling the output of a neutron generator tube of the deuterium-tritium accelerator type and having an ion source to produce sharply defined pulses of neutrons for well logging use. It comprises: means for inputting a relatively low voltage input control pulse having a leading edge and a trailing edge; means, responsive to the input control pulse, for producing a relatively high voltage ion source voltage pulse after receipt of the input pulse; and means, responsive to the input control pulse, for quenching, after receipt of the input pulse, the ion source control pulse, thereby providing a sharply time defined neutron output from the generator tube

  9. Metallic ions in the upper atmosphere

    International Nuclear Information System (INIS)

    Kumar, S.

    1979-01-01

    During the past 20 years considerable progress has been made in establishing the presence of metallic ions in the sporadic E layers at mid latitudes and as discrete patches at high altitudes in the equatorial ionosphere. The E-region observations have been based on rocket flights, which represent local conditions faithfully. But the global distribution of metallic ions and variations relating to changes in season, local time, magnetic activity, etc., which require satellite data, have been largely unexamined. This work presents a few aspects of this missing global distribution over an altitude range of 100 to 1000 km, using the data from AE-C, AE-D, and OGO-6 satellites and the rocket flights 18.117 and 18.118 from Wallops Island on July 12 and 13, 1971. The rocket data provide a day-night pair of vertical profiles that include altitudes not covered by the satellites. Results are presented for Mg + , Al + , Si + and Fe + ions in terms of their detection probabilities, median concentrations and relative abundances with respect to Mg + ions as a function of significant geophysical parameters. Na + and K + ions have been excluded from this study because alkali metal ions driven off the spacecraft hamper the measurement of ambient Na + and K + ions. This study has indicated that in general different metallic ions appear together in comparable concentrations except for Al + , which is an order of magnitude smaller than the others

  10. Vacuum Arc Ion Sources

    CERN Document Server

    Brown, I.

    2013-12-16

    The vacuum arc ion source has evolved into a more or less standard laboratory tool for the production of high-current beams of metal ions, and is now used in a number of different embodiments at many laboratories around the world. Applications include primarily ion implantation for material surface modification research, and good performance has been obtained for the injection of high-current beams of heavy-metal ions, in particular uranium, into particle accelerators. As the use of the source has grown, so also have the operational characteristics been improved in a variety of different ways. Here we review the principles, design, and performance of vacuum arc ion sources.

  11. Selection and design of ion sources for use at the Holifield radioactive ion beam facility

    International Nuclear Information System (INIS)

    Alton, G.D.; Haynes, D.L.; Mills, G.D.; Olsen, D.K.

    1994-01-01

    The Holifield Radioactive Ion Beam Facility now under construction at the Oak Ridge National Laboratory will use the 25 MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility. The choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. Although direct-extraction negative ion sources are clearly desirable, the ion formation efficiencies are often too low for practical consideration; for this situation, positive ion sources, in combination with charge exchange, are the logical choice. The high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the facility because of its low emittance, relatively high ionization efficiencies, and species versatility, and because it has been engineered for remote installation, removal, and servicing as required for safe handling in a high-radiation-level ISOL facility. The source will be primarily used to generate ion beams from elements with intermediate to low electron affinities. Prototype plasma-sputter negative ion sources and negative surface-ionization sources are under design consideration for generating radioactive ion beams from high-electron-affinity elements. The design features of these sources and expected efficiencies and beam qualities (emittances) will be described in this report

  12. Ion bombardment modification of surfaces

    International Nuclear Information System (INIS)

    Auciello, O.

    1984-01-01

    Ion bombardment-induced modification of surfaces may be considered one of the significant scientific and technological developments of the last two decades. The understanding acquired concerning the underlying mechanisms of several phenomena occurring during ion-surface interactions has led to applications within different modern technologies. These include microelectronics, surface acoustical and optical technologies, solar energy conversion, thin film technology, ion implantation metallurgy, nuclear track technology, thermonuclear fusion, vacuum technology, cold welding technology, biomedicine (implantology). It has become clear that information on many relevant advances, regarding ion bombardment modification of surfaces is dispersed among journals involving fields sometimes not clearly related. This may result, in some cases, in a loss of the type of interdisciplinary exchange of ideas, which has proved to be so fruitful for the advancement of science and technology. This book has been planned in an attempt to collect at least some of today's relevant information about the experimental and theoretical knowledge related to surface modification and its application to technology. (Auth.)

  13. Heavy-ion radiography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.; Woodruff, K.H.; MacFarland, E.W.

    1983-01-01

    High energy, heavy-ion beams offer superior discrimination of tissue electron densities at very low radiation doses. This characteristic has potential for diagnostic medical imaging of neoplasms arising in the soft tissues and organs because it can detect smaller inhomogeneities than x rays. Heavy-ion imaging may also increase the accuracy of cancer radiotherapy planning involving use of accelerated charged particles. In the current physics research program of passive heavy-ion imaging, critical modulation transfer function tests are being carried out in heavy-ion projection radiography and heavy-ion computerized tomography. The research goal is to improve the heavy-ion imaging method until it reaches the limits of its theoretical resolution defined by range straggling, multiple scattering, and other factors involved in the beam quality characteristics. Clinical uses of the imaging method include the application of heavy-ion computerized tomography to heavy-ion radiotherapy planning, to the study of brain tumors and other structures of the head, and to low-dose heavy-ion projection mammography, particularly for women with dense breasts where other methods of diagnosis fail. The ions used are primarily 300 to 570 MeV/amu carbon and neon ions accelerated at the Lawrence Berkeley Laboratory Bevalac

  14. Pick-up ion energization at the termination shock

    Energy Technology Data Exchange (ETDEWEB)

    Gary, S Peter [Los Alamos National Laboratory; Winske, Dan [Los Alamos National Laboratory; Wu, Pin [BOSTON UNIV.; Schwadron, N A [BOSTON UNIV.

    2009-01-01

    One-dimensional hybrid simulations are used to investigate how pickup ions are energized at the perpendicular termination shock. Contrary to previous models based on pickup ion energy gain by repeated crossings of the shock front (shock surfing) or due to a reforming shock front, the present simulations show that pickup ion energy gain involves a gyro-phasedependent interaction with the inhomogeneous motional electric field at the shock. The process operates at all relative concentrations of pickup ion density.

  15. Crater formation by single ions, cluster ions and ion "showers"

    CERN Document Server

    Djurabekova, Flyura; Timko, Helga; Nordlund, Kai; Calatroni, Sergio; Taborelli, Mauro; Wuensch, Walter

    2011-01-01

    The various craters formed by giant objects, macroscopic collisions and nanoscale impacts exhibit an intriguing resemblance in shapes. At the same time, the arc plasma built up in the presence of sufficiently high electric fields at close look causes very similar damage on the surfaces. Although the plasma–wall interaction is far from a single heavy ion impact over dense metal surfaces or the one of a cluster ion, the craters seen on metal surfaces after a plasma discharge make it possible to link this event to the known mechanisms of the crater formations. During the plasma discharge in a high electric field the surface is subject to high fluxes (~1025 cm-2s-1) of ions with roughly equal energies typically of the order of a few keV. To simulate such a process it is possible to use a cloud of ions of the same energy. In the present work we follow the effect of such a flux of ions impinging the surface in the ‘‘shower’’ manner, to find the transition between the different mechanisms of crater formati...

  16. A New Platform for Profiling Degradation-Related Impurities Via Exploiting the Opportunities Offered by Ion-Selective Electrodes: Determination of Both Diatrizoate Sodium and Its Cytotoxic Degradation Product.

    Science.gov (United States)

    Riad, Safaa M; Abd El-Rahman, Mohamed K; Fawaz, Esraa M; Shehata, Mostafa A

    2018-05-01

    Although the ultimate goal of administering active pharmaceutical ingredients (APIs) is to save countless lives, the presence of impurities and/or degradation products in APIs or formulations may cause harmful physiological effects. Today, impurity profiling (i.e., the identity as well as the quantity of impurity in a pharmaceutical) is receiving critical attention from regulatory authorities. Despite the predominant use of spectroscopic and chromatographic methods over electrochemical methods for impurity profiling of APIs, this work investigates the opportunities offered by electroanalytical methods, particularly, ion-selective electrodes (ISEs), for profiling degradation-related impurities (DRIs) compared with conventional spectroscopic and chromatographic methods. For a meaningful comparison, diatrizoate sodium (DTA) was chosen as the anionic X-ray contrast agent based on its susceptibility to deacetylation into its cytotoxic and mutagenic degradation product, 3,5-diamino-2,4,6 triiodobenzoic acid (DTB). This cationic diamino compound can be also detected as an impurity in the final product because it is used as a synthetic precursor for the synthesis of DTA. In this study, four novel sensitive and selective sensors for the determination of both DTA and its cytotoxic degradation products are presented. Sensors I and II were developed for the determination of the anionic drug, DTA, and sensors III and IV were developed for the determination of the cationic cytotoxic impurity. The use of these novel sensors not only provides a stability-indicating method for the selective determination of DTA in the presence of its degradation product, but also permits DRI profiling. Moreover, a great advantage of these proposed ISE systems is their higher sensitivity for the quantification of DTB relative to other spectroscopic and chromatographic methods, so it can measure trace amounts of DTB impurities in DTA bulk powder and pharmaceutical formulation without a need for

  17. Calculation of ion storage in electron beams with account of ion-ion interactions

    International Nuclear Information System (INIS)

    Perel'shtejn, Eh.A.; Shirkov, G.D.

    1979-01-01

    Ion storage in relativistic electron beams was calculated taking account of ion-ion charge exchange and ionization. The calculations were made for nitrogen ion storage from residual gas during the compression of electron rings in the adhezator of the JINR heavy ion accelerator. The calculations were made for rings of various parameters and for various pressures of the residual gas. The results are compared with analogous calculations made without account of ion-ion processes. It is shown that at heavy loading of a ring by ions ion-ion collisions play a significant part, and they should be taken into account while calculating ion storage

  18. Ion sources for initial use at the Holifield radioactive ion beam facility

    International Nuclear Information System (INIS)

    Alton, G.D.

    1994-01-01

    The Holifield Radioactive Ion Beam Facility (HRIBF) now under construction at the Oak Ridge National Laboratory will use the 25-MV tandem accelerator for the acceleration of radioactive ion beams to energies appropriate for research in nuclear physics; negative ion beams are, therefore, required for injection into the tandem accelerator. Because charge exchange is an efficient means for converting initially positive ion beams to negative ion beams, both positive and negative ion sources are viable options for use at the facility; the choice of the type of ion source will depend on the overall efficiency for generating the radioactive species of interest. A high-temperature version of the CERN-ISOLDE positive ion source has been selected and a modified version of the source designed and fabricated for initial use at the HRIBF because of its low emittance, relatively high ionization efficiencies and species versatility, and because it has been engineered for remote installation, removal and servicing as required for safe handling in a high-radiation-level ISOL facility. Prototype plasma-sputter negative ion sources and negative surfaceionization sources are also under design consideration for generating negative radioactive ion beams from high electron-affinity elements. A brief review of the HRIBF will be presented, followed by a detailed description of the design features, operational characteristics, ionization efficiencies, and beam qualities (emittances) of these sources

  19. Dendritic ion channelopathy in acquired epilepsy

    Science.gov (United States)

    Poolos, Nicholas P.; Johnston, Daniel

    2012-01-01

    Summary Ion channel dysfunction or “channelopathy” is a proven cause of epilepsy in the relatively uncommon genetic epilepsies with Mendelian inheritance. But numerous examples of acquired channelopathy in experimental animal models of epilepsy following brain injury have also been demonstrated. Our understanding of channelopathy has grown due to advances in electrophysiology techniques that have allowed the study of ion channels in the dendrites of pyramidal neurons in cortex and hippocampus. The apical dendrites of pyramidal neurons comprise the vast majority of neuronal surface membrane area, and thus the majority of the neuronal ion channel population. Investigation of dendritic ion channels has demonstrated remarkable plasticity in ion channel localization and biophysical properties in epilepsy, many of which produce hyperexcitability and may contribute to the development and maintenance of the epileptic state. Here we review recent advances in dendritic physiology and cell biology, and their relevance to epilepsy. PMID:23216577

  20. Nitridation of vanadium by ion beam irradiation

    International Nuclear Information System (INIS)

    Kiuchi, Masato; Chayahara, Akiyoshi; Kinomura, Atsushi; Ensinger, Wolfgang

    1994-01-01

    The nitridation of vanadium by ion beam irradiation is studied by the ion implantation method and the dynamic mixing method. The nitrogen ion implantation was carried out into deposited V(110) films. Using both methods, three phases are formed, i.e. α-V, β-V 2 N, and δ-VN. Which phases are formed is related to the implantation dose or the arrival ratio. The orientation of the VN films produced by the dynamic ion beam mixing method is (100) and that of the VN films produced by the ion implantation method is (111). The nitridation of vanadium is also discussed in comparison with that of titanium and chromium. ((orig.))

  1. Electrodialytic separation of alkali-element ions with the aid of ion-exchange membranes

    International Nuclear Information System (INIS)

    Gurskii, V.S.; Moskvin, L.N.

    1988-01-01

    Electrodialytic separation of ions bearing charges of the same sign with the aid of ion-exchange membranes has been examined in the literature in relation to the so-called ideal membranes, which do not exhibit selectivity with respect to one ion type in ion exchange. It has been shown that separation on such membranes is effective only for counterions differing in size of charge. A matter of greater importance from the practical standpoint is the possibility of using electrodialysis for separating ions bearing like charges and having similar properties, including ionic forms of isotopes of the same element. In this paper they report a comparative study of ion separation, with reference to the Cs-Na pair, by electrodialysis through various types of cation-exchange membranes. Changes of the solution concentration in the cathode compartment were monitored by measurement of 22 Na and 137 Cs activities

  2. Duopigatron ion source studies

    International Nuclear Information System (INIS)

    Bacon, F.M.; Bickes, R.W. Jr.; O'Hagan, J.B.

    1978-07-01

    Ion source performance characteristics consisting of total ion current, ion energy distribution, mass distribution, and ion current density distribution were measured for several models of a duopigatron. Variations on the duopigatron design involved plasma expansion cup material and dimensions, secondary cathode material, and interelectrode spacings. Of the designs tested, the one with a copper and molybdenum secondary cathode and a mild steel plasma expansion cup proved to give the best results. The ion current density distribution was peaked at the center of the plasma expansion cup and fell off to 80 percent of the peak value at the cup wall for a cup 15.2 mm deep. A total ion current of 180 mA consisting of 60 to 70 percent atomic ions was produced with an arc current of 20 A and source pressure of 9.3 Pa. More shallow cups produced a larger beam current and a more sharply peaked ion current density distribution. Typical ion energy distributions were bell-shaped curves with a peak 10 to 20 V below anode potential and with ion energies extending 30 to 40 V on either side of the peak

  3. Ion Motion Stability in Asymmetric Surface Electrode Ion Traps

    Science.gov (United States)

    Shaikh, Fayaz; Ozakin, Arkadas

    2010-03-01

    Many recently developed designs of the surface electrode ion traps for quantum information processing have asymmetry built into their geometries. The asymmetry helps rotate the trap axes to angles with respect to electrode surface that facilitate laser cooling of ions but introduces a relative angle between the RF and DC fields and invalidates the classical stability analysis of the symmetric case for which the equations of motion are decoupled. For asymmetric case the classical motion of a single ion is given by a coupled, multi-dimensional version of Mathieu's equation. In this poster we discuss the stability diagram of asymmetric surface traps by performing an approximate multiple scale perturbation analysis of the coupled Mathieu equations, and validate the results with numerical simulations. After obtaining the stability diagram for the linear fields, we simulate the motion of an ion in a given asymmetric surface trap, utilizing a method-of-moments calculation of the electrode fields. We obtain the stability diagram and compare it with the ideal case to find the region of validity. Finally, we compare the results of our stability analysis to experiments conducted on a microfabricated asymmetric surface trap.

  4. Quantitative ion implantation

    International Nuclear Information System (INIS)

    Gries, W.H.

    1976-06-01

    This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

  5. Ion species stratification within strong shocks in two-ion plasmas

    Science.gov (United States)

    Keenan, Brett D.; Simakov, Andrei N.; Taitano, William T.; Chacón, Luis

    2018-03-01

    Strong collisional shocks in multi-ion plasmas are featured in many environments, with Inertial Confinement Fusion (ICF) experiments being one prominent example. Recent work [Keenan et al., Phys. Rev. E 96, 053203 (2017)] answered in detail a number of outstanding questions concerning the kinetic structure of steady-state, planar plasma shocks, e.g., the shock width scaling by the Mach number, M. However, it did not discuss shock-driven ion-species stratification (e.g., relative concentration modification and temperature separation). These are important effects since many recent ICF experiments have evaded explanation by standard, single-fluid, radiation-hydrodynamic (rad-hydro) numerical simulations, and shock-driven fuel stratification likely contributes to this discrepancy. Employing the state-of-the-art Vlasov-Fokker-Planck code, iFP, along with multi-ion hydro simulations and semi-analytics, we quantify the ion stratification by planar shocks with the arbitrary Mach number and the relative species concentration for two-ion plasmas in terms of ion mass and charge ratios. In particular, for strong shocks, we find that the structure of the ion temperature separation has a nearly universal character across ion mass and charge ratios. Additionally, we find that the shock fronts are enriched with the lighter ion species and the enrichment scales as M4 for M ≫ 1.

  6. Ion extraction in the cyclotron geometry

    International Nuclear Information System (INIS)

    Rodenburg, R.E.

    1985-01-01

    The detailed physics of ion beam extraction from a plasma column by intense sinusoidal radio frequency (rf) electric fields at the ion cyclotron frequency omega/sub ci/ and its harmonics is experimentally studied. Results describe the instantaneous relationship - within one rf period of approx. = 3009 nsec - between applied rf, the plasma response and the ions expelled by rf and plasma fields. Reflex discharges in H 2 , D 2 , and He with ion and electron densities greater than or equal to10 11 cm -3 are subjected to 0-5 kV zero-to-peak rf electric fields E vector and 0.65-9.00 kG background magnetic fields B 0 vector with E vector perpendicular to B 0 vector. Ion currents up to 200 μA are extracted. Nonperturbing optical diagnostics measure the relative amplitude and phase of instantaneous ion and electron density fluctuations induced by the rf during each rf cycle and the time variation of extracted ion bursts, the latter made possible by the use of a phosphor beam-stop. Detailed dependences on external electric and magnetic fields are reported. The plasma density fluctuations are in good agreement with the dispersion relation for electrostatic ion cyclotron waves (EICW), and the beam data show current enhancement at the second harmonic over that at the fundamental and evidence for a radically different mechanism for the rf-driven ion extraction process than conventional wisdom assumes. This work represents the first detailed, systematic study of the ac ion extraction process

  7. Heating tokamaks via the ion-cyclotron and ion-ion hybrid resonances

    International Nuclear Information System (INIS)

    Perkins, F.W.

    1977-04-01

    For the ion-ion hybrid resonance it is shown that: (1) the energy absorption occurs via a sequence of mode conversions; (2) a poloidal field component normal to the ion-ion hybrid mode conversion surface strongly influences the mode conversion process so that roughly equal electron and ion heating occurs in the present proton-deuterium experiments, while solely electron heating is predicted to prevail in deuterium-tritium reactors; (3) the ion-ion hybrid resonance suppresses toroidal eigenmodes; and (4) wave absorption in minority fundamental ion-cyclotron heating experiments will be dominated by ion-ion hybrid mode conversion absorption for minority concentrations exceeding roughly 1 percent. For the ion-cyclotron resonance, it is shown that: (1) ion-cyclotron mode conversion leads to surface electron heating; and (2) ion-cyclotron mode conversion absorption dominates fundamental ion-cyclotron absorption thereby preventing efficient ion heating

  8. Wettability control of polystyrene by ion implantation

    International Nuclear Information System (INIS)

    Suzuki, Yoshiaki; Kusakabe, Masahiro; Iwaki, Masaya

    1994-01-01

    The permanent effects of ion implantation on the improvement of wettability of polystyrene is investigated in relation to ion species and fluences. The He + , Ne + , Na + , N 2 + , O 2 + , Ar + , K + and Kr + ion implantations were performed at energies of 50 and 150 keV at room temperature. The fluences ranged from 1x10 15 to 1x10 17 ions/cm 2 . The results showed that the contact angle of water for Na + and K + implanted polystyrene decreased from 87 to 0 , as the fluences increased to 1x10 17 ions/cm 2 at an energy of 50 keV. The contact angle for Na + and K + implanted polystyrene did not change under ambient room conditions, even when time elapsed. However, the contact an gle for He + , C + , O + , Ne + , N 2 + , O 2 + , Ar + , and Kr + ion implanted specimens decreased slightly immediately after ion implantation. Results of X-ray photoelectron spectroscopy showed that the increase in the Na content in the surface of Na + implanted specimens were observed with increasing fluence. It is concluded that permanent improvement in wettability was caused by doping effects rather than by radiation effects from Na + and K + ion implantation. ((orig.))

  9. Gaseous odd- and even-electron ions

    International Nuclear Information System (INIS)

    Wagner, W.; Heimbach, H.; Levsen, K.

    1980-01-01

    The principal collision-induced fragmentations of simple protonated ketones, aldehydes, ethers, amines, sulphides, alcohols, acids, nitriles and halides are discussed. These protonated molecules decompose mainly by loss of alkane, alkene and RX (R = alkyl, H; X = OH, SH, NH 2 , Br, I). Substantial radical losses are only observed for small protonated molecules. Deuterium-labelling demonstrates that the X-H bond is particularly strong. The fragmentation of (MH) + ions is compared with that of the corresponding (M) + sup(.) ions is compared with that of the corresponding (M) + sup(.) ions. The spectra of the (M) + sup(.) ions are dominated by direct bond cleavages, in particular α-cleavages, as a result of both the stability of the ionic fragment and the loose transition state. In (MH) + ions direct bond cleavages lead to energetically less favourable products. Thus rearrangement reactions play a more important role in the decomposition of these ions. (MH) + ions are more stable relative to fragmentation than (M) + sup(.) ions. (orig.)

  10. Atmospheric ions and pollution

    International Nuclear Information System (INIS)

    Renoux, A.

    1977-01-01

    The various types of atmospheric ions are defined, the main sources of natural atmospheric radioactivity inducing the formation of radioactive ions in the air are then recalled. The basic equations governing the formation of these ions are indicated and the most current experimental methods used for detecting them are described (Zeleny tubes, Erikson tubes). The special properties of these ions are examined, they are particularly emphasized for the smaller ones. The existence of a discret spectrum of mobilities is shown and the presence of big negative radioactive ions is investigated. Indicative information are given on the granulometric distribution of the atmospheric radioactivity in the air, from small positive Ra A ion fixation on aerosols [fr

  11. Materials analysis fast ions

    CERN Document Server

    Denker, A; Rauschenberg, J; Röhrich, J; Strub, E

    2006-01-01

    Materials analysis with ion beams exploits the interaction of ions with the electrons and nuclei in the sample. Among the vast variety of possible analytical techniques available with ion beams we will restrain to ion beam analysis with ion beams in the energy range from one to several MeV per mass unit. It is possible to use either the back-scattered projectiles (RBS – Rutherford Back Scattering) or the recoiled atoms itself (ERDA – Elastic Recoil Detection Analysis) from the elastic scattering processes. These techniques allow the simultaneous and absolute determination of stoichiometry and depth profiles of the detected elements. The interaction of the ions with the electrons in the sample produces holes in the inner electronic shells of the sample atoms, which recombine and emit X-rays characteristic for the element in question. Particle Induced X-ray Emission (PIXE) has shown to be a fast technique for the analysis of elements with an atomic number above 11.

  12. Ion thruster performance model

    International Nuclear Information System (INIS)

    Brophy, J.R.

    1984-01-01

    A model of ion thruster performance is developed for high flux density cusped magnetic field thruster designs. This model is formulated in terms of the average energy required to produce an ion in the discharge chamber plasma and the fraction of these ions that are extracted to form the beam. The direct loss of high energy (primary) electrons from the plasma to the anode is shown to have a major effect on thruster performance. The model provides simple algebraic equations enabling one to calculate the beam ion energy cost, the average discharge chamber plasma ion energy cost, the primary electron density, the primary-to-Maxwellian electron density ratio and the Maxwellian electron temperature. Experiments indicate that the model correctly predicts the variation in plasma ion energy cost for changes in propellant gas (Ar, Kr, and Xe), grid transparency to neutral atoms, beam extraction area, discharge voltage, and discharge chamber wall temperature

  13. Ion emission microscope microanalyzer

    International Nuclear Information System (INIS)

    Cherepin, V.T.; Olckovsky, V.L.

    1977-01-01

    In the ion microanalyzer (microprobe) the object is exposed to the bombardment of a highly focused ion beam, the secondary ions emitted from the object being analyzed by means of a mass filter. In order to be able to control the position of an analysis synchronous to the local analysis of an object an ion-optical converter (electron image with a fluorescent screen) is placed behind the aperture diaphragm in the direction of the secondary ion beam. The converter allows to make visible in front of the mass filter a non-split ion image characterizing the surface of the surface investigated. Then a certain section may be selected for performing chemical and isotope analyses. (DG) [de

  14. Outlook for ion exchange

    International Nuclear Information System (INIS)

    Kunin, R.

    1977-01-01

    This paper presents the history and theory of ion exchange technology and discusses the usefulness of ion exchange resins which found broad applications in chemical operations. It is demonstrated that the theory of ion exchange technology seems to be moving away from the physical chemist back to the polymer chemist where it started originally. This but confronted the polymer chemists with some knotty problems. It is pointed out that one has still to learn how to use ion exchange materials as efficiently as possible in terms of the waste load that is being pumped into the environment. It is interesting to note that, whereas ion exchange is used for abating pollution, it is also a polluter. One must learn how to use ion exchange as an antipollution device, and at the same time minimize its polluting properties

  15. HEAVY ION LINEAR ACCELERATOR

    Science.gov (United States)

    Van Atta, C.M.; Beringer, R.; Smith, L.

    1959-01-01

    A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

  16. Spatially-Resolved Ion Trajectory Measurements During Cl2 Reactive Ion Beam Etching and Ar Ion Beam Etching

    International Nuclear Information System (INIS)

    Vawter, G. Allen; Woodworth, Joseph R.; Zubrzycki, Walter J.

    1999-01-01

    The angle of ion incidence at the etched wafer location during RIBE and IBE using Cl 2 , Ar and O 2 ion beams has been characterized using an ion energy and angle analyzer. Effects of beam current and accelerator grid bias on beam divergence and the spatial uniformity of the spread of incident angles are measured. It is observed that increased total beam current can lead to reduced current density at the sample stage due to enhanced beam divergence at high currents. Results are related to preferred etch system design for uniform high-aspect-ratio etching across semiconductor wafers

  17. Isotope separation by ion waves

    International Nuclear Information System (INIS)

    Dawson, J.M.

    1978-01-01

    One of the isotopes of an element having several isotopes can be separated from the others in a dense, neutral plasma. Thus initially a neutral plasma is prepared including the element in question. This may consist of positive ions and negative electrons or alternatively of positive and negative ions, or else of a mixture of positive ions, negative ions and electrons. The plasma may then be injected into a magnetic field or may be generated in the field where more energy is imparted to a selected isotope than to the others. Finally, the isotopes are separated from each other on the basis of their differential energies. For example, the selected isotope may be given more energy than the others by stimulating it within the plasma at its resonant frequency which may be close to the cyclotron frequency, either by an electric field or by a magnetic field. In order to excite the other isotope, a different resonant frequency is required which depends on the plasma density, the relative concentration of electrons if the plasma contains electrons, the strength of the magnetic field, the ratio of charge to mass of the isotope, and possibly on the physical parameters of the plasma apparatus itself, such as the ratio of the length of the plasma column to its radius. The more energetic isotope may be separated by energy dependent chemical reactions, it may be collected by a positively biased probe or else the isotopes may be separated from each other by magnetic fields or in various other ways

  18. Electron-ion collisions

    International Nuclear Information System (INIS)

    Crandall, D.H.

    1982-01-01

    This discussion concentrates on basic physics aspects of inelastic processes of excitation, ionization, and recombination that occur during electron-ion collisions. Except for cases of illustration along isoelectronic sequences, only multicharged (at least +2) ions will be specifically discussed with some emphasis of unique physics aspects associated with ionic charge. The material presented will be discussed from a primarily experimental viewpoint with most attention to electron-ion interacting beams experiments

  19. Ion implantation in semiconductors

    International Nuclear Information System (INIS)

    Gusev, V.; Gusevova, M.

    1980-01-01

    The historical development is described of the method of ion implantation, the physical research of the method, its technological solution and practical uses. The method is universally applicable, allows the implantation of arbitrary atoms to an arbitrary material, ensures high purity of the doping element. It is linked with sample processing at low temperatures. In implantation it is possible to independently change the dose and energy of the ions thereby affecting the spatial distribution of the ions. (M.S.)

  20. Ion implantation in semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Gusev, V; Gusevova, M

    1980-06-01

    The historical development of the method of ion implantation, the physical research of the method, its technological solution and practical uses is described. The method is universally applicable, allows the implantation of arbitrary atoms to an arbitrary material and ensures high purity of the doping element. It is linked with sample processing at low temperatures. In implantation it is possible to independently change the dose and energy of the ions thereby affecting the spatial distribution of the ions.

  1. Ion implantation in metals

    International Nuclear Information System (INIS)

    Vook, F.L.

    1977-02-01

    The application of ion beams to metals is rapidly emerging as a promising area of research and technology. This report briefly describes some of the recent advances in the modification and study of the basic properties of metals by ion implantation techniques. Most of the research discussed illustrates some of the new and exciting applications of ion beams to metals which are under active investigation at Sandia Laboratories, Albuquerque

  2. Heavy-ion targets

    International Nuclear Information System (INIS)

    Adair, H.L.; Kobisk, E.H.

    1985-01-01

    This chapter examines the characteristics of targets required in heavy-ion accelerator physics experiments. The effects of target parameters on heavy-ion experimental results are reviewed. The target fabrication and characterization techniques used to minimize experimental problems during heavy-ion bombardment are described. Topics considered include target thickness and uniformity, target lifetime, target purity, substrate materials, Doppler shift effects, metal preparations, and target preparation methods

  3. Cluster ion beam facilities

    International Nuclear Information System (INIS)

    Popok, V.N.; Prasalovich, S.V.; Odzhaev, V.B.; Campbell, E.E.B.

    2001-01-01

    A brief state-of-the-art review in the field of cluster-surface interactions is presented. Ionised cluster beams could become a powerful and versatile tool for the modification and processing of surfaces as an alternative to ion implantation and ion assisted deposition. The main effects of cluster-surface collisions and possible applications of cluster ion beams are discussed. The outlooks of the Cluster Implantation and Deposition Apparatus (CIDA) being developed in Guteborg University are shown

  4. Neutron ion temperature measurement

    International Nuclear Information System (INIS)

    Strachan, J.D.; Hendel, H.W.; Lovberg, J.; Nieschmidt, E.B.

    1986-11-01

    One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n) 3 He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques

  5. Ion transport in stellarators

    International Nuclear Information System (INIS)

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    Stellarator ion transport in the low-collisionality regime with a radial electric field is calculated by a systematic expansion of the drift-Boltzmann equation. The shape of the helical well is taken into account in this calculation. It is found that the barely trapped ions with three to four times the thermal energy give the dominant contribution to the diffusion. Expressions for the ion particle and energy fluxes are derived

  6. Ion optics in an ion source system

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Salam, F W; Moustafa, O A; El-Khabeary, H [Accelerators Dept, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    1997-12-31

    An analysis of ion beams from an ion source which consisted of a hemispherical anode, a plane earthed cathode, and a focusing electrode has been carried out. The focal properties of such electrode arrangement were studied using axially symmetric fields. Axial and radial electric fields were obtained as functions of the axial distance. It was found that the radial component of the gradient of potential pushes the ions towards the axis, which indicates the convergent action of the system. The effect of voltage variation between the boundary and the focusing electrode on the position of the plasma boundary are given using the experimental data of the ion source characteristics and its geometrical parameters. The advantages of plasma diffusing outside the source through a small aperture were used by applying a potential to the focusing electrode. It was possible to extract a large ion current from the expanded plasma. The system constituted a lens with a focal length of 29.4 mm. 7 figs.

  7. Ion trap device

    Science.gov (United States)

    Ibrahim, Yehia M.; Smith, Richard D.

    2016-01-26

    An ion trap device is disclosed. The device includes a series of electrodes that define an ion flow path. A radio frequency (RF) field is applied to the series of electrodes such that each electrode is phase shifted approximately 180 degrees from an adjacent electrode. A DC voltage is superimposed with the RF field to create a DC gradient to drive ions in the direction of the gradient. A second RF field or DC voltage is applied to selectively trap and release the ions from the device. Further, the device may be gridless and utilized at high pressure.

  8. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  9. Correlation ion mobility spectroscopy

    Science.gov (United States)

    Pfeifer, Kent B [Los Lunas, NM; Rohde, Steven B [Corrales, NM

    2008-08-26

    Correlation ion mobility spectrometry (CIMS) uses gating modulation and correlation signal processing to improve IMS instrument performance. Closely spaced ion peaks can be resolved by adding discriminating codes to the gate and matched filtering for the received ion current signal, thereby improving sensitivity and resolution of an ion mobility spectrometer. CIMS can be used to improve the signal-to-noise ratio even for transient chemical samples. CIMS is especially advantageous for small geometry IMS drift tubes that can otherwise have poor resolution due to their small size.

  10. Heavy ion storage rings

    International Nuclear Information System (INIS)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented. 35 refs

  11. Electrochemical evidences and consequences of significant differences in ions diffusion rate in polyacrylate-based ion-selective membranes.

    Science.gov (United States)

    Woźnica, Emilia; Mieczkowski, Józef; Michalska, Agata

    2011-11-21

    The origin and effect of surface accumulation of primary ions within the ion-selective poly(n-butyl acrylate)-based membrane, obtained by thermal polymerization, is discussed. Using a new method, based on the relation between the shape of a potentiometric plot and preconditioning time, the diffusion of copper ions in the membrane was found to be slow (the diffusion coefficient estimated to be close to 10(-11) cm(2) s(-1)), especially when compared to ion-exchanger counter ions--sodium cations diffusion (a diffusion coefficient above 10(-9) cm(2) s(-1)). The higher mobility of sodium ions than those of the copper-ionophore complex results in exposed ion-exchanger role leading to undesirably exposed sensitivity to sodium or potassium ions.

  12. Development of a four-zone carousel process packed with metal ion-imprinted polymer for continuous separation of copper ions from manganese ions, cobalt ions, and the constituent metal ions of the buffer solution used as eluent.

    Science.gov (United States)

    Jo, Se-Hee; Park, Chanhun; Yi, Sung Chul; Kim, Dukjoon; Mun, Sungyong

    2011-08-19

    A three-zone carousel process, in which Cu(II)-imprinted polymer (Cu-MIP) and a buffer solution were employed as adsorbent and eluent respectively, has been developed previously for continuous separation of Cu²⁺ (product) from Mn²⁺ and Co²⁺ (impurities). Although this process was reported to be successful in the aforementioned separation task, the way of using a buffer solution as eluent made it inevitable that the product stream included the buffer-related metal ions (i.e., the constituent metal ions of the buffer solution) as well as copper ions. For a more perfect recovery of copper ions, it would be necessary to improve the previous carousel process such that it can remove the buffer-related metal ions from copper ions while maintaining the previous function of separating copper ions from the other 2 impure heavy-metal ions. This improvement was made in this study by proposing a four-zone carousel process based on the following strategy: (1) the addition of one more zone for performing the two-step re-equilibration tasks and (2) the use of water as the eluent of the washing step in the separation zone. The operating conditions of such a proposed process were determined on the basis of the data from a series of single-column experiments. Under the determined operating conditions, 3 runs of carousel experiments were carried out. The results of these experiments revealed that the feed-loading time was a key parameter affecting the performance of the proposed process. Consequently, the continuous separation of copper ions from both the impure heavy-metal ions and the buffer-related metal ions could be achieved with a purity of 91.9% and a yield of 92.8% by using the proposed carousel process based on a properly chosen feed-loading time. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. An online low energy gaseous ion source

    International Nuclear Information System (INIS)

    Jin Shuoxue; Guo Liping; Peng Guoliang; Zhang Jiaolong; Yang Zheng; Li Ming; Liu Chuansheng; Ju Xin; Liu Shi

    2010-01-01

    The accumulation of helium and/or hydrogen in nuclear materials may cause performance deterioration of the materials. In order to provide a unique tool to investigate the He-and/or H-caused problems, such as interaction of helium with hydrogen and defects, formation of gas bubbles and its evolution, and the related effects, we designed a low energy (≤ 20 keV) cold cathode Penning ion source, which will be interfaced to a 200 kV transmission electron microscope (TEM), for monitoring continuously the evolution of micro-structure during the He + or H + ion implantation. Studies on discharge voltage-current characteristics of the ion source, and extraction and focusing of the ion beam were performed. The ion source works stably with 15-60 mA of the discharge current.Under the gas pressure of 5 x 10 -3 Pa and 1.5 x 10 -2 Pa, the discharge voltage are about 380 V and 320 V, respectively. The extracted ion current under lower gas pressure is greater than that under higher gas pressure, and it increases with the discharge current and extraction voltage. The ion lens consisting of three equal-diameter metal cylinder focus the ion beam effectively, so that the beam density at the 150 cm away from the lens exit increases by a over one order of magnitude. For ion beams of around 10 keV, the measured beam density is about 200 nA · cm -2 , which is applicable for ion implantation and in situ TEM observation for many kinds of nuclear materials. (authors)

  14. Recent advances in high current vacuum arc ion sources for heavy ion fusion

    CERN Document Server

    Qi Nian Sheng; Prasad, R R; Krishnan, M S; Anders, A; Kwan, J; Brown, I

    2001-01-01

    For a heavy ion fusion induction linac driver, a source of heavy ions with charge states 1+-3+, approx 0.5 A current beams, approx 20 mu s pulse widths and approx 10 Hz repetition rates is required. Thermionic sources have been the workhorse for the Heavy Ion Fusion (HIF) program to date, but suffer from heating problems for large areas and contamination. They are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states in short and long pulse bursts and high beam current density. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications was investigated. We have modifie...

  15. Ion-beam technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fenske, G.R. [Argonne National Lab., IL (United States)

    1993-01-01

    This compilation of figures and diagrams reviews processes for depositing diamond/diamond-like carbon films. Processes addressed are chemical vapor deposition (HFCVD, PACVD, etc.), plasma vapor deposition (plasma sputtering, ion beam sputtering, evaporation, etc.), low-energy ion implantation, and hybrid processes (biased sputtering, IBAD, biased HFCVD, etc.). The tribological performance of coatings produced by different means is discussed.

  16. Ion beam studies

    International Nuclear Information System (INIS)

    Freeman, J.H.; Chivers, D.J.; Gard, G.A.; Temple, W.

    1977-04-01

    A description of techniques for the production of intense beams of heavy ions is given. A table of recommended operational procedures for most elements is included. The ionisation of boron is considered in some detail because of its particular importance as a dopant for ion implantation. (author)

  17. Where do ions solvate?

    Indian Academy of Sciences (India)

    We study a simple model of ionic solvation inside a water cluster. The cluster is modeled as a spherical dielectric continuum. It is found that unpolarizable ions always prefer the bulk solvation. On the other hand, for polarizable ions, there exists a critical value of polarization above which surface solvation becomes ...

  18. Ion implantation of metals

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1976-01-01

    In this part of the paper descriptions are given of the effects of ion implantation on (a) friction and wear in metals; and (b) corrosion of metals. In the study of corrosion, ion implantation can be used either to introduce a constituent that is known to convey corrosion resistance, or more generally to examine the parameters which control corrosion. (U.K.)

  19. Heavy ion fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1986-01-01

    This report on the International Symposium on Heavy Ion Fusion held May 27-29, 1986 summarizes the problems and achievements in the areas of targets, accelerators, focussing, reactor studies, and system studies. The symposium participants recognize that there are large uncertainties in Heavy Ion Fusion but many of them are also optimistic that HIF may ultimately be the best approach to fusion

  20. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Fessenden, T.J.; Friedman, A.

    1991-01-01

    This report describes the research status in the following areas of research in the field of heavy ion inertial fusion: (1) RF accelerators, storage rings, and synchrotrons; (2) induction linacs; (3) recirculation induction accelerator approach; (4) a new accelerator concept, the ''Mirrortron''; (5) general issues of transport, including beam merging, production of short, fat quadrupoles with nearly linear focusing, calculations of beam behaviour in image fields; 3-D electrostatic codes on drift compression with misalignments and transport around bends; (6) injectors, ion sources and RFQs, a.o., on the development of a 27 MHz RFQ to be used for the low energy portion of a new injector for all ions up to Uranium, and the development of a 2 MV carbon ion injector to provide 16 C + beams of 0.5 A each for ILSE; (7) beam transport from accelerator to target, reporting, a.o., the feasibility to suppress third-order aberrations; while Particle-in-Cell simulations on the propagation of a non-neutral ion beam in a low density gas identified photo-ionization by thermal X-rays from the target as an important source of defocusing; (9) heavy ion target studies; (10) reviewing experience with laser drivers; (11) ion cluster stopping and muon catalyzed fusion; (12) heavy ion systems, including the option of a fusion-fission burner. 1 tab

  1. Ion mobility sensor system

    Science.gov (United States)

    Xu, Jun; Watson, David B.; Whitten, William B.

    2013-01-22

    An ion mobility sensor system including an ion mobility spectrometer and a differential mobility spectrometer coupled to the ion mobility spectrometer. The ion mobility spectrometer has a first chamber having first end and a second end extending along a first direction, and a first electrode system that generates a constant electric field parallel to the first direction. The differential mobility spectrometer includes a second chamber having a third end and a fourth end configured such that a fluid may flow in a second direction from the third end to the fourth end, and a second electrode system that generates an asymmetric electric field within an interior of the second chamber. Additionally, the ion mobility spectrometer and the differential mobility spectrometer form an interface region. Also, the first end and the third end are positioned facing one another so that the constant electric field enters the third end and overlaps the fluid flowing in the second direction.

  2. Cryogenic surface ion traps

    International Nuclear Information System (INIS)

    Niedermayr, M.

    2015-01-01

    Microfabricated surface traps are a promising architecture to realize a scalable quantum computer based on trapped ions. In principle, hundreds or thousands of surface traps can be located on a single substrate in order to provide large arrays of interacting ions. To this end, trap designs and fabrication methods are required that provide scalable, stable and reproducible ion traps. This work presents a novel surface-trap design developed for cryogenic applications. Intrinsic silicon is used as the substrate material of the traps. The well-developed microfabrication and structuring methods of silicon are utilized to create simple and reproducible traps. The traps were tested and characterized in a cryogenic setup. Ions could be trapped and their life time and motional heating were investigated. Long ion lifetimes of several hours were observed and the measured heating rates were reproducibly low at around 1 phonon per second at a trap frequency of 1 MHz. (author) [de

  3. Molecular ion photofragment spectroscopy

    International Nuclear Information System (INIS)

    Bustamente, S.W.

    1983-11-01

    A new molecular ion photofragment spectrometer is described which features a supersonic molecular beam ion source and a radio frequency octapole ion trap interaction region. This unique combination allows several techniques to be applied to the problem of detecting a photon absorption event of a molecular ion. In particular, it may be possible to obtain low resolution survey spectra of exotic molecular ions by using a direct vibrational predissociation process, or by using other more indirect detection methods. The use of the spectrometer is demonstrated by measuring the lifetime of the O 2 + ( 4 π/sub u/) metastable state which is found to consist of two main components: the 4 π/sub 5/2/ and 4 π/sub -1/2/ spin components having a long lifetime (approx. 129 ms) and the 4 π/sub 3/2/ and 4 π/sub 1/2/ spin components having a short lifetime (approx. 6 ms)

  4. Progress in liquid ion exchangers

    International Nuclear Information System (INIS)

    Nakagawa, Genkichi

    1974-01-01

    Review is made on the extraction with anion exchangers and the extraction with liquid cation exchangers. On the former, explanation is made on the extraction of acids, the relation between anion exchange and the extraction of metals, the composition of the metallic complexes that are extracted, and the application of the extraction with anion exchangers to analytical chemistry. On the latter, explanation is made on the extraction of metals and its application to analytical chemistry. The extraction with liquid ion exchangers is suitable for the operation in chromatography, because the distribution of extracting agents into aqueous phase is small, and extraction equilibrium is quickly reached, usually within 1 to several minutes. The separation by means of anion exchangers is usually made from hydrochloric acid solution. For example, Brinkman et al. determined Rf values for more than 50 elements by thin layer chromatography. Tables are given for showing the structure of the liquid ion exchangers and the polymerized state of various amines. (Mori, K.)

  5. Quantitative determination of acidic hydrolysis products of Chemical Weapons Convention related chemicals from aqueous and soil samples using ion-pair solid-phase extraction and in situ butylation.

    Science.gov (United States)

    Pal Anagoni, Suresh; Kauser, Asma; Maity, Gopal; Upadhyayula, Vijayasarathi V R

    2018-02-01

    Chemical warfare agents such as organophosphorus nerve agents, mustard agents, and psychotomimetic agent like 3-quinuclidinylbenzilate degrade in the environment and form acidic degradation products, the analysis of which is difficult under normal analytical conditions. In the present work, a simultaneous extraction and derivatization method in which the analytes are butylated followed by gas chromatography and mass spectrometric identification of the analytes from aqueous and soil samples was carried out. The extraction was carried out using ion-pair solid-phase extraction with tetrabutylammonium hydroxide followed by gas chromatography with mass spectrometry in the electron ionization mode. Various parameters such as optimum concentration of the ion-pair reagent, pH of the sample, extraction solvent, and type of ion-pair reagent were optimized. The method was validated for various parameters such as linearity, accuracy, precision, and limit of detection and quantification. The method was observed to be linear from 1 to 1000 ng/mL range in selected ion monitoring mode. The extraction recoveries were in the range of 85-110% from the matrixes with the limit of quantification for alkyl phosphonic acids at 1 ng/mL, thiodiglycolic acid at 20 ng/mL, and benzilic acid at 50 ng/mL with intra- and interday precisions below 15%. The developed method was applied for the samples prepared in the scenario of challenging inspection. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Test of special relativity theory by means of laser spectroscopy on relativistic {sup 7}Li{sup +} ions in the ESR; Test der Speziellen Relativitaetstheorie mittels Laserspektroskopie an relativistischen {sup 7}Li{sup +}-Ionen am ESR

    Energy Technology Data Exchange (ETDEWEB)

    Botermann, Benjamin

    2012-10-31

    The invariance under Lorentz transformation of the laws of physics is a fundamental postulate of modern physics and all theories of the fundamental interactions have been stated in a covariant form. Although the theory of Special Relativity (SR) has been tested and confirmed with high accuracy in a large number of experiments, improved tests are of fundamental interest due to the far-reaching relevance of this postulate. Additionally modern attempts of a unified description of the four fundamental interactions point to possible violations of Lorentz invariance. In this context experiments of the Ives-Stilwell type for a test of time dilation play an important role. High resolution laser spectroscopy is applied on relativistic particle beams to investigate the validity of the relativistic Doppler formula - and therefore of the time dilation factor γ. In the course of this thesis an Ives-Stilwell experiment was performed with {sup 7}Li{sup +} ions at a velocity of 34 % of the speed of light, which were stored at the experimental storage ring (ESR) of the GSI Helmholtzzentrum fuer Schwerionenforschung. The techniques of Λ- as well as saturation spectroscopy were employed on the 1s2s{sup 3}S{sub 1}→1s2p{sup 3}P{sub 2} transition. By a computer based analysis of the fluorescence detection system and utilization of appropriate edge filters the signal to noise ratio was decisively improved and the application of an additional pump laser allowed for the observation of a saturation signal for the first time. The frequency stability of both laser systems was specified by means of a frequency comb to obtain the highest possible accuracy. The data from the beam times were analyzed in the frameworks of the Robertson-Mansouri-Sexl test theory (RMS) and the Standard Model Extension (SME) and the corresponding upper limits of the relevant test parameters of the assigned theories were calculated. The upper limit of the parameter α was improved by a factor of 4 compared to

  7. Synchrotron-radiation experiments with recoil ions

    International Nuclear Information System (INIS)

    Levin, J.C.

    1989-01-01

    Studies of atoms, ions and molecules with synchrotron radiation have generally focused on measurements of properties of the electrons ejected during, or after, the photoionization process. Much can also be learned, however, about the atomic or molecular relaxation process by studies of the residual ions or molecular fragments following inner-shell photoionization. Measurements are reported of mean kinetic energies of highly charged argon, krypton, and xenon recoil ions produced by vacancy cascades following inner-shell photoionization using white and monochromatic synchrotron x radiation. Energies are much lower than for the same charge-state ions produced by charged-particle impact. The results may be applicable to design of future angle-resolved ion-atom collision experiments. Photoion charge distributions are presented and compared with other measurements and calculations. Related experiments with synchrotron-radiation produced recoil ion, including photoionization of stored ions and measurement of shakeoff in near-threshold excitation, are briefly discussed. 24 refs., 6 figs., 1 tab

  8. Ion thermometers - nuclear reactor applications

    International Nuclear Information System (INIS)

    Rosenkranz, J.; Jakes, D.

    The principle is briefly described of ion thermometers and the effects are reported of radiation on the ion crystal properties. The results show that ion thermometers are applicable for in-core measurements. (J.P.)

  9. Study of the negative ion extraction mechanism from a double-ion plasma in negative ion sources

    International Nuclear Information System (INIS)

    Goto, I.; Nishioka, S.; Hatayama, A.; Miyamoto, K.

    2015-01-01

    We have developed a 2D3V-PIC model of the extraction region, aiming to clarify the basic extraction mechanism of H − ions from the double-ion plasma in H − negative ion sources. The result shows the same tendency of the H − ion density n H − as that observed in the experiments, i.e.,n H − in the upstream region away from the plasma meniscus (H − emitting surface) has been reduced by applying the extraction voltage. At the same time, relatively slow temporal oscillation of the electric potential compared with the electron plasma frequency has been observed in the extraction region. Results of the systematic study using a 1D3V-PIC model with the uniform magnetic field confirm the result that the electrostatic oscillation is identified to be lower hybrid wave. The effect of this oscillation on the H − transport will be studied in the future

  10. Semiconductor Ion Implanters

    International Nuclear Information System (INIS)

    MacKinnon, Barry A.; Ruffell, John P.

    2011-01-01

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  11. Plasma source ion implantation

    International Nuclear Information System (INIS)

    Conrad, J.R.; Forest, C.

    1986-01-01

    The authors' technique allows the ion implantation to be performed directly within the ion source at higher currents without ion beam extraction and transport. The potential benefits include greatly increased production rates (factors of 10-1000) and the ability to implant non-planar targets without rastering or shadowing. The technique eliminates the ion extractor grid set, beam raster equipment, drift space and target manipulator equipment. The target to be implanted is placed directly within the plasma source and is biased to a large negative potential so that plasma ions gain energy as they accelerate through the potential drop across the sheath that forms at the plasma boundary. Because the sheath surrounds the target on all sides, all surfaces of the target are implanted without the necessity to raster the beam or to rotate the target. The authors have succeeded in implanting nitrogen ions in a silicon target to the depths and concentrations required for surface treatment of materials like stainless steel and titanium alloys. They have performed ESCA measurements of the penetration depth profile of a silicon target that was biased to 30 kV in a nitrogen discharge plasma. Nitrogen ions were implanted to a depth of 700A at a peak concentration of 30% atomic. The measured profile is quite similar to a previously obtained profile in titanium targets with conventional techniques

  12. Laser-cooled atomic ions as probes of molecular ions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Kenneth R.; Viteri, C. Ricardo; Clark, Craig R.; Goeders, James E.; Khanyile, Ncamiso B.; Vittorini, Grahame D. [Schools of Chemistry and Biochemistry, Computational Science and Engineering and Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2015-01-22

    Trapped laser-cooled atomic ions are a new tool for understanding cold molecular ions. The atomic ions not only sympathetically cool the molecular ions to millikelvin temperatures, but the bright atomic ion fluorescence can also serve as a detector of both molecular reactions and molecular spectra. We are working towards the detection of single molecular ion spectra by sympathetic heating spectroscopy. Sympathetic heating spectroscopy uses the coupled motion of two trapped ions to measure the spectra of one ion by observing changes in the fluorescence of the other ion. Sympathetic heating spectroscopy is a generalization of quantum logic spectroscopy, but does not require ions in the motional ground state or coherent control of the ion internal states. We have recently demonstrated this technique using two isotopes of Ca{sup +} [Phys. Rev. A, 81, 043428 (2010)]. Limits of the method and potential applications for molecular spectroscopy are discussed.

  13. Ion-induced particle desorption in time-of-flight medium energy ion scattering

    Science.gov (United States)

    Lohmann, S.; Primetzhofer, D.

    2018-05-01

    Secondary ions emitted from solids upon ion impact are studied in a time-of-flight medium energy ion scattering (ToF-MEIS) set-up. In order to investigate characteristics of the emission processes and to evaluate the potential for surface and thin film analysis, experiments employing TiN and Al samples were conducted. The ejected ions exhibit a low initial kinetic energy of a few eV, thus, requiring a sufficiently high acceleration voltage for detection. Molecular and atomic ions of different charge states originating both from surface contaminations and the sample material are found, and relative yields of several species were determined. Experimental evidence that points towards a predominantly electronic sputtering process is presented. For emitted Ti target atoms an additional nuclear sputtering component is suggested.

  14. Ion acoustic waves in pair-ion plasma: Linear and nonlinear analyses

    International Nuclear Information System (INIS)

    Saeed, R.; Mushtaq, A.

    2009-01-01

    Linear and nonlinear properties of low frequency ion acoustic wave (IAW) in pair-ion plasma in the presence of electrons are investigated. The dispersion relation and Kadomtsev-Petviashvili equation for linear/nonlinear IAW are derived from sets of hydrodynamic equations where the ion pairs are inertial while electrons are Boltzmannian. The dispersion curves for various concentrations of electrons are discussed and compared with experimental results. The predicted linear IAW propagates at the same frequencies as those of the experimentally observed IAW if n e0 ∼10 4 cm -3 . It is found that nonlinear profile of the ion acoustic solitary waves is significantly affected by the percentage ratio of electron number density and temperature. It is also determined that rarefactive solitary waves can propagate in this system. It is hoped that the results presented in this study would be helpful in understanding the salient features of the finite amplitude localized ion acoustic solitary pulses in a laboratory fullerene plasma.

  15. Ion beam induced luminescence from diamond using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A A; Jamieson, D N; Prawer, S; Allen, M G [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1994-12-31

    Analysis of the luminescence induced by a MeV ion beam offers the potential to provide useful information about the chemical properties of atoms in crystals to complement the information provided by more traditional Ion Beam Analysis (IBA) such as Rutherford Backscattering Spectrometry (RBS), ion channeling and Particle Induced X-ray Emission (PIXE). Furthermore, the large penetration depth of the MeV ion beam offers several advantages over the relatively shallow penetration of keV electrons typically employed in cathodoluminescence. An Ion Beam Induced Luminescence (IBIL) detection system was developed for the Melbourne microprobe that allows the spatial mapping of the luminescence signal along with the signals from RBS and PIXE. Homoepitaxial diamond growth has been studied and remarkable shifts in the characteristic blue luminescence of diamond towards the green were observed in the overgrowth. This has been tentatively identified as being due to transition metal inclusions in the epitaxial layers. 8 refs., 2 refs.

  16. Ion beam induced luminescence from diamond using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A.A.; Jamieson, D. N.; Prawer, S.; Allen, M.G. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1993-12-31

    Analysis of the luminescence induced by a MeV ion beam offers the potential to provide useful information about the chemical properties of atoms in crystals to complement the information provided by more traditional Ion Beam Analysis (IBA) such as Rutherford Backscattering Spectrometry (RBS), ion channeling and Particle Induced X-ray Emission (PIXE). Furthermore, the large penetration depth of the MeV ion beam offers several advantages over the relatively shallow penetration of keV electrons typically employed in cathodoluminescence. An Ion Beam Induced Luminescence (IBIL) detection system was developed for the Melbourne microprobe that allows the spatial mapping of the luminescence signal along with the signals from RBS and PIXE. Homoepitaxial diamond growth has been studied and remarkable shifts in the characteristic blue luminescence of diamond towards the green were observed in the overgrowth. This has been tentatively identified as being due to transition metal inclusions in the epitaxial layers. 8 refs., 2 refs.

  17. Complementary scattered and recoiled ion data from TOF-E heavy ion elastic recoil detection analysis

    International Nuclear Information System (INIS)

    Johnston, P.N.; El Bouanani, M.; Stannard, W.B.; Bubb, I.F.; Cohen, D.D.; Dytlewski, N.; Siegele, R.

    1998-01-01

    The advantage of Time of Flight and Energy (ToF-E) Heavy Ion Elastic Recoil Detection Analysis (HIERDA) over Rutherford Backscattering (RBS) analysis is its mass and energy dispersive capabilities. The mass resolution of ToF-E HIERDA deteriorates for very heavy elements. The limitation is related to the poor energy resolution of Si detectors for heavy ions. While the energy spectra from ToF-E HIERDA data are normally used to extract depth profiles, this work discusses the benefits of using the time spectra of both the recoiled and the scattered ions for depth profiling. The simulation of the complementary scattered and recoiled ion time spectra improves depth profiling and reduced current limitations when dealing with very heavy ions, such as Pt, Bi, Ta. (authors)

  18. Negative secondary ion emission from oxidized surfaces

    International Nuclear Information System (INIS)

    Gnaser, H.; Kernforschungsanlage Juelich G.m.b.H.

    1984-01-01

    The emission of negative secondary ions from 23 elements was studied for 10 keV O 2 + and 10 keV In + impact at an angle of incidence of 45 0 . Partial oxidation of the sample surfaces was achieved by oxygen bombardment and/or by working at a high oxygen partial pressure. It was found that the emission of oxide ions shows an element-characteristic pattern. For the majority of the elements investigated these features are largely invariant against changes of the surface concentration of oxygen. For the others admission of oxygen strongly changes the relative intensities of oxide ions: a strong increase of MO 3 - signals (M stands for the respective element) is accompanied by a decrease of MO - and M - intensities. Different primary species frequently induce changes of both the relative and the absolute negative ion intensities. Carbon - in contrast to all other elements - does not show any detectable oxide ion emission but rather intense cluster ions Csub(n) - (detected up to n=12) whose intensities oscillate in dependence on n. (orig./RK)

  19. Ion implantation as an efficient surface treatment

    International Nuclear Information System (INIS)

    Straede, C.A.

    1992-01-01

    Ion beam processing has for several years been well established in the semiconductor industry. In recent years ion implantation of tool steels, ceramics and even plastics has gained increasing industrial awareness. The development of ion implantation to a commercially viable surface treatment of tools and spare parts working in production type environments is very dependent on technical merits, economic considerations, competing processes and highly individual barriers to acceptance for each particular application. Some examples of this will be discussed. The development of the process is very closely linked with the development of high current accelerators and their ability to efficiently manipulate the samples being treated, or to make sample manipulation superfluous by using special beam systems like the PSII. Furthermore, the ability to produce high beam currents (mA) of a wide variety of ions is crucial. Previously, it was broadly accepted that ion implantation of tools on a commercial basis generally had to be limited to nitrogen implantation. The development of implanters which can produce high beam currents of ions like B + , C + , Ti + , Cr + and others is rapidly changing this situation, and today an increasing number of commercial implantations are performed with these ions although nitrogen is still successfully used in the majority of commercial implantation. All in all, the recent development of equipment makes it possible to a higher extent than before to tailor the implantation to a specific situation. The emerging new possibilities in this direction will be discussed, and a broad selection of practical examples of ion implantation at standard low temperatures of tools and spare parts will be given. Furthermore, very interesting results have been obtained recently by implanting nitrogen at elevated temperatures, which yields a relatively deep penetration of the implanted ions. (orig./WL)

  20. Image-projection ion-beam lithography

    International Nuclear Information System (INIS)

    Miller, P.A.

    1989-01-01

    Image-projection ion-beam lithography is an attractive alternative for submicron patterning because it may provide high throughput; it uses demagnification to gain advantages in reticle fabrication, inspection, and lifetime; and it enjoys the precise deposition characteristics of ions which cause essentially no collateral damage. This lithographic option involves extracting low-mass ions (e.g., He + ) from a plasma source, transmitting the ions at low voltage through a stencil reticle, and then accelerating and focusing the ions electrostatically onto a resist-coated wafer. While the advantages of this technology have been demonstrated experimentally by the work of IMS (Austria), many difficulties still impede extension of the technology to the high-volume production of microelectronic devices. We report a computational study of a lithography system designed to address problem areas in field size, telecentricity, and chromatic and geometric aberration. We present a novel ion-column-design approach and conceptual ion-source and column designs which address these issues. We find that image-projection ion-beam technology should in principle meet high-volume-production requirements. The technical success of our present relatively compact-column design requires that a glow-discharge-based ion source (or equivalent cold source) be developed and that moderate further improvement in geometric aberration levels be obtained. Our system requires that image predistortion be employed during reticle fabrication to overcome distortion due to residual image nonlinearity and space-charge forces. This constitutes a software data preparation step, as do correcting for distortions in electron lithography columns and performing proximity-effect corrections. Areas needing further fundamental work are identified

  1. Impulsive ion acceleration in earth's outer magnetosphere

    International Nuclear Information System (INIS)

    Baker, D.N.; Belian, R.D.

    1985-01-01

    Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions are not of dominant importance for magnetotail plasma dynamics, they serve as an important tracer population. Their absolute intensity and brief temporal appearance bespeaks a strong and rapid acceleration process in the near-tail, very probably involving large induced electric fields substantially greater than those associated with cross-tail potential drops. Subsequent to their impulsive acceleration, these ions are injected into the outer trapping regions forming ion ''drift echo'' events, as well as streaming tailward away from their acceleration site in the near-earth plasma sheet. Most auroral ion acceleration processes occur (or are greatly enhanced) during the time that these global magnetospheric events are occurring in the magnetotail. A qualitative model relating energetic ion populations to near-tail magnetic reconnection at substorm onset followed by global redistribution is quite successful in explaining the primary observational features. Recent measurements of the elemental composition and charge-states have proven valuable for showing the source (solar wind or ionosphere) of the original plasma population from which the ions were accelerated

  2. Heavy-ion dosimetry

    International Nuclear Information System (INIS)

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained

  3. Ion implantation technology

    CERN Document Server

    Downey, DF; Jones, KS; Ryding, G

    1993-01-01

    Ion implantation technology has made a major contribution to the dramatic advances in integrated circuit technology since the early 1970's. The ever-present need for accurate models in ion implanted species will become absolutely vital in the future due to shrinking feature sizes. Successful wide application of ion implantation, as well as exploitation of newly identified opportunities, will require the development of comprehensive implant models. The 141 papers (including 24 invited papers) in this volume address the most recent developments in this field. New structures and possible approach

  4. IN MEMORIAM ION VATAMANU

    Directory of Open Access Journals (Sweden)

    S.P. Palii

    2012-12-01

    Full Text Available A dreamer in his creative solitude, an objective and lucid analyst of history and contemporaneity, an energetic and decisive leader with an uncanny ability for crisis management – all these describe Ion Vatamanu. His wife Elena and daughters Mihaela, Mariana, Leontina treasure a personal universe in which the magical spark of Ion Vatamanu’s love and joy of life meld the everyday in and out of poetry. Ion Vatamanu’s instantaneous connection to the audiences and deeply felt words still touch the hearts of his many colleagues and friends. Downloads: 2

  5. Ion implantation for microelectronics

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1977-01-01

    Ion implantation has proved to be a versatile and efficient means of producing microelectronic devices. This review summarizes the relevant physics and technology and assesses the advantages of the method. Examples are then given of widely different device structures which have been made by ion implantation. While most of the industrial application has been in silicon, good progress continues to be made in the more difficult field of compound semiconductors. Equipment designed for the industrial ion implantation of microelectronic devices is discussed briefly. (Auth.)

  6. Multivalent ion conducting solids

    Energy Technology Data Exchange (ETDEWEB)

    Imanaka, N. [Osaka Univ., Suita, Osaka (Japan). Dept. of Applied Chemistry

    2008-07-01

    Solid electrolytes possess important characteristics for industrial applications. Only a single ionic species can macroscopically migrate in these solids. This paper described a the new NASICON (M-Zr-Nb-P-O) type system, exhibiting an exceptionally high level of trivalent M3+ ion conductivity on polycrystalline solids. The partial substitution of the smaller higher valent Nb5+ ion for Zr4+ stabilized the NASICON phase and realized the M3+ ion conduction in the NASICON structure. It was concluded that the conductivities of the series are comparable to those of the practically applied solid electrolytes of oxide anion conductors of YSZ and CSZ. 3 refs., 2 figs.

  7. Heavy ion physics

    International Nuclear Information System (INIS)

    Kalpakchieva, R.; Cherepanov, E.A.

    1993-01-01

    The international school-seminar on heavy ion physics had been organized in Dubna in may of 1993. The scientific program of reports covers the following main topics: synthesis and properties of heavy nuclei; synthesis and investigation of properties of exotic nuclei; experiments with radioactive nuclear beams; interaction between complex nuclei at low and intermediate energies. It also includes reports on laser spectroscopy and exotic nuclear beams, on some application of heavy ion beams for the problems of solid state physics, on construction of multidetector facilities and on developing of heavy ion accelerator complexes. Short communication

  8. Compact microwave ion source

    International Nuclear Information System (INIS)

    Leung, K.N.; Walther, S.; Owren, H.W.

    1985-05-01

    A small microwave ion source has been fabricated from a quartz tube with one end enclosed by a two grid accelerator. The source is also enclosed by a cavity operated at a frequency of 2.45 GHz. Microwave power as high as 500 W can be coupled to the source plasma. The source has been operated with and without multicusp fields for different gases. In the case of hydrogen, ion current density of 200 mA/cm -2 with atomic ion species concentration as high as 80% has been extracted from the source

  9. Jet laser ion source

    International Nuclear Information System (INIS)

    Dem'yanov, A.V.; Sidorov, S.V.

    1994-01-01

    External laser injector of multicharged ions (MCI) is developed in which wide-aperture aberration-free wire gauze spherical shape electrodes are applied for effective MCI extraction from laser plasma and beam focusing. Axial plasma compression by solenoid magnetic field is used to reduce ion losses due to transverse movement of the scattering laser plasma. Transverse magnetic field created by another solenoid facilitates the effective laser plasma braking and consequently, leads to the narrowing of energy spectrum of plasma ions and its shift towards lower energies. 2 refs.; 3 figs

  10. Carbon Ion Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, David Christoffer; Herrmann, Rochus

    On the importance of choice of target size for selective boosting of hypoxic tumor subvolumina in carbon ion therapy Purpose: Functional imaging methods in radiotherapy are maturing and can to some extent uncover radio resistant structures found within a tumour entity. Selective boost of identified...... effect. All cell lines investigated here did not reach an OER of 1, even for the smaller structures, which may indicate that the achievable dose average LET of carbon ions is too low, and heavier ions than carbon may be considered for functional LET-painting....

  11. Atlas positive-ion injector project

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, R C; Bollinger, L M; Shepard, K W

    1987-04-01

    The goal of the Argonne Positive Ion Injector project is to replace the ATLAS tandem injector with a facility which will increase the beam currents presently available by a factor of 100 and to make beams of essentially all elements including uranium available at ATLAS. The beam quality expected from the facility will be at least as good as that of the tandem based ATLAS. The project combines two relatively new technologies - the electron cyclotron resonance ion source, which provides ions of high charge states at microampere currents, and rf superconductivity which has been shown to be capable of generating accelerating fields as high as 10 MV/m resulting in an essentially new method of acceleration for low-energy heavy ions.

  12. Multiple ionization of atoms by ion impact

    International Nuclear Information System (INIS)

    DuBois, R.D.

    1988-01-01

    In order to model the energy deposition of fast ions as they slow down in gaseous media, information about the ionization occurring in collisions between ions and target atoms/molecules is required. Our measurements of doubly differential electron emission cross sections provide detailed information about the ionization process but do not provide any information about the final states of the target. They also do not distinguish between the emission of one or more target electrons in a single collision. It is important to know the relative importance of multiple-, with respect to single-, target ionization in order to accurately model the energy deposition. To date, multiple ionization of He, Ne, Ar, Kr, and Xe targets has been studied. Primarily, H and He ions were used, although some data for heavier ions (C,N and O) have also been obtained

  13. Applications of the ion microprobe to geochemistry and cosmochemistry

    International Nuclear Information System (INIS)

    Shimizu, N.; Hart, S.R.

    1982-01-01

    When a solid surface is subjected to a bombardment of energetic ions, material is ejected from the surface in a process known as sputtering. A part of the sputtered material is ionized and these secondary ions can be analyzed with a mass spectrometer according to a technique known as secondary ion mass spectrometry (SIMS). A description is presented of the present status of geochemical and cosmochemical applications of the ion microprobe. Attention is given to the sputtering event, molecular ion interferences, aspects of isotopic fractionation, secondary ion intensities in polycomponent materials, and questions of trace element analysis. Geochemical applications of the ion microprobe are based on certain advantages over other analytical techniques. These advantages are related to high sensitivity, low background, and the capability of in situ analysis of isotopic composition. The distribution of trace elements in minerals is considered, along with isotope anomalies, isotope zoning, diffusion studies, and depth profiling

  14. Characterizing Ion Flows Across a Dipolarization Front

    Science.gov (United States)

    Arnold, H.; Drake, J. F.; Swisdak, M.

    2017-12-01

    In light of the Magnetospheric Multiscale Mission (MMS) moving to study predominately symmetric magnetic reconnection in the Earth's magnetotail, it is of interest to investigate various methods for determining the relative location of the satellites with respect to the x line or a dipolarization front. We use a 2.5 dimensional PIC simulation to explore the dependence of various characteristics of a front, or flux bundle, on the width of the front in the dawn-dusk direction. In particular, we characterize the ion flow in the x-GSM direction across the front. We find a linear relationship between the width of a front, w, and the maximum velocity of the ion flow in the x-GSM direction, Vxi, for small widths: Vxi/VA=w/di*1/2*(mVA2)/Ti*Bz/Bxwhere m, VA, di, Ti, Bz, and Bx are the ion mass, upstream Alfven speed, ion inertial length, ion temperature, and magnetic fields in the z-GSM and x-GSM directions respectively. However, once the width reaches around 5 di, the relationship gradually approaches the well-known theoretical limit for ion flows, the upstream Alfven speed. Furthermore, we note that there is a reversal in the Hall magnetic field near the current sheet on the positive y-GSM side of the front. This reversal is most likely due to conservation of momentum in the y-GSM direction as the ions accelerate towards the x-GSM direction. This indicates that while the ions are primarily energized in the x-GSM direction by the front, they transfer energy to the electromagnetic fields in the y-GSM direction. The former energy transfer is greater than the latter, but the reversal of the Hall magnetic field drags the frozen-in electrons along with it outside of the front. These simulations should better able researchers to determine the relative location of a satellite crossing a dipolarization front.

  15. Fully kinetic simulation of ion acoustic and dust-ion acoustic waves

    International Nuclear Information System (INIS)

    Hosseini Jenab, S. M.; Kourakis, I.; Abbasi, H.

    2011-01-01

    A series of numerical simulations is presented, based on a recurrence-free Vlasov kinetic model using kinetic phase point trajectories. All plasma components are modeled kinetically via a Vlasov evolution equation, then coupled through Poisson's equation. The dynamics of ion acoustic waves in an electron-ion and in a dusty (electron-ion-dust) plasma configuration are investigated, focusing on wave decay due to Landau damping and, in particular, on the parametric dependence of the damping rate on the dust concentration and on the electron-to-ion temperature ratio. In the absence of dust, the occurrence of damping was observed, as expected, and its dependence to the relative magnitude of the electron vs ion temperature(s) was investigated. When present, the dust component influences the charge balance, enabling dust-ion acoustic waves to survive Landau damping even in the extreme regime where T e ≅ T i . The Landau damping rate is shown to be minimized for a strong dust concentration or/and for a high value of the electron-to-ion temperature ratio. Our results confirm earlier theoretical considerations and contribute to the interpretation of experimental observations of dust-ion acoustic wave characteristics.

  16. Single ion induced surface nanostructures: a comparison between slow highly charged and swift heavy ions.

    Science.gov (United States)

    Aumayr, Friedrich; Facsko, Stefan; El-Said, Ayman S; Trautmann, Christina; Schleberger, Marika

    2011-10-05

    This topical review focuses on recent advances in the understanding of the formation of surface nanostructures, an intriguing phenomenon in ion-surface interaction due to the impact of individual ions. In many solid targets, swift heavy ions produce narrow cylindrical tracks accompanied by the formation of a surface nanostructure. More recently, a similar nanometric surface effect has been revealed for the impact of individual, very slow but highly charged ions. While swift ions transfer their large kinetic energy to the target via ionization and electronic excitation processes (electronic stopping), slow highly charged ions produce surface structures due to potential energy deposited at the top surface layers. Despite the differences in primary excitation, the similarity between the nanostructures is striking and strongly points to a common mechanism related to the energy transfer from the electronic to the lattice system of the target. A comparison of surface structures induced by swift heavy ions and slow highly charged ions provides a valuable insight to better understand the formation mechanisms. © 2011 IOP Publishing Ltd

  17. Fast-ion Dα measurements of the fast-ion distribution (invited)

    International Nuclear Information System (INIS)

    Heidbrink, W. W.

    2010-01-01

    The fast-ion Dα (FIDA) diagnostic is an application of charge-exchange recombination spectroscopy. Fast ions that neutralize in an injected neutral beam emit Balmer-α light with a large Doppler shift. The spectral shift is exploited to distinguish the FIDA emission from other bright sources of Dα light. Background subtraction is the main technical challenge. A spectroscopic diagnostic typically achieves temporal, energy, and transverse spatial resolution of ∼1 ms, ∼10 keV, and ∼2 cm, respectively. Installations that use narrow-band filters achieve high spatial and temporal resolution at the expense of spectral information. For high temporal resolution, the bandpass-filtered light goes directly to a photomultiplier, allowing detection of ∼50 kHz oscillations in FIDA signal. For two-dimensional spatial profiles, the bandpass-filtered light goes to a charge-coupled device camera; detailed images of fast-ion redistribution at instabilities are obtained. Qualitative and quantitative models relate the measured FIDA signals to the fast-ion distribution function. The first quantitative comparisons between theory and experiment found excellent agreement in beam-heated magnetohydrodynamics (MHD)-quiescent plasmas. FIDA diagnostics are now in operation at magnetic-fusion facilities worldwide. They are used to study fast-ion acceleration by ion cyclotron heating, to detect fast-ion transport by MHD modes and microturbulence, and to study fast-ion driven instabilities.

  18. Multifactorial Understanding of Ion Abundance in Tandem Mass Spectrometry Experiments.

    Science.gov (United States)

    Fazal, Zeeshan; Southey, Bruce R; Sweedler, Jonathan V; Rodriguez-Zas, Sandra L

    2013-01-29

    In a bottom-up shotgun approach, the proteins of a mixture are enzymatically digested, separated, and analyzed via tandem mass spectrometry. The mass spectra relating fragment ion intensities (abundance) to the mass-to-charge are used to deduce the amino acid sequence and identify the peptides and proteins. The variables that influence intensity were characterized using a multi-factorial mixed-effects model, a ten-fold cross-validation, and stepwise feature selection on 6,352,528 fragment ions from 61,543 peptide ions. Intensity was higher in fragment ions that did not have neutral mass loss relative to any mass loss or that had a +1 charge state. Peptide ions classified for proton mobility as non-mobile had lowest intensity of all mobility levels. Higher basic residue (arginine, lysine or histidine) counts in the peptide ion and low counts in the fragment ion were associated with lower fragment ion intensities. Higher counts of proline in peptide and fragment ions were associated with lower intensities. These results are consistent with the mobile proton theory. Opposite trends between peptide and fragment ion counts and intensity may be due to the different impact of factor under consideration at different stages of the MS/MS experiment or to the different distribution of observations across peptide and fragment ion levels. Presence of basic residues at all three positions next to the fragmentation site was associated with lower fragment ion intensity. The presence of proline proximal to the fragmentation site enhanced fragmentation and had the opposite trend when located distant from the site. A positive association between fragment ion intensity and presence of sulfur residues (cysteine and methionine) on the vicinity of the fragmentation site was identified. These results highlight the multi-factorial nature of fragment ion intensity and could improve the algorithms for peptide identification and the simulation in tandem mass spectrometry experiments.

  19. Charge transfer processes during ion scattering and stimulated desorption of secondary ions from gas-condensed dielectric surfaces

    CERN Document Server

    Souda, R

    2002-01-01

    The ion emission mechanism from weakly-interacting solid surfaces has been investigated. The H sup + ion captures a valence electron via transient chemisorption, so that the ion neutralization probability is related to the nature of bonding of adsorbates. The H sup + ion is scattered from physisorbed Ar at any coverage whereas the H sup + yield from solid H sub 2 O decays considerably due to covalency in the hydrogen bond. In electron- and ion-stimulated desorption, the ion ejection probability is correlated intimately with the physisorption/chemisorption of parent atoms or molecules. The emission of F sup + ions is rather exceptional because they arise from the screened F 2s core-hole state followed by the ionization via the intra-atomic Auger decay after bond breakage. In electron-stimulated desorption of H sub 2 O, hydrated protons are emitted effectively from nanoclusters formed on a solid Ar substrate due to Coulomb repulsion between confined valence holes.

  20. Atomic negative ions

    International Nuclear Information System (INIS)

    Brage, T.

    1991-01-01

    We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given

  1. Ion exchange phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  2. Sensing with Ion Channels

    CERN Document Server

    Martinac, Boris

    2008-01-01

    All living cells are able to detect and translate environmental stimuli into biologically meaningful signals. Sensations of touch, hearing, sight, taste, smell or pain are essential to the survival of all living organisms. The importance of sensory input for the existence of life thus justifies the effort made to understand its molecular origins. Sensing with Ion Channels focuses on ion channels as key molecules enabling biological systems to sense and process the physical and chemical stimuli that act upon cells in their living environment. Its aim is to serve as a reference to ion channel specialists and as a source of new information to non specialists who want to learn about the structural and functional diversity of ion channels and their role in sensory physiology.

  3. Trapping radioactive ions

    CERN Document Server

    Kluge, Heinz-Jürgen

    2004-01-01

    Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning.

  4. Ion sensing method

    Science.gov (United States)

    Smith, Richard Harding; Martin, Glenn Brian

    2004-05-18

    The present invention allows the determination of trace levels of ionic substances in a sample solution (ions, metal ions, and other electrically charged molecules) by coupling a separation method, such as liquid chromatography, with ion selective electrodes (ISE) prepared so as to allow detection at activities below 10.sup.-6 M. The separation method distributes constituent molecules into fractions due to unique chemical and physical properties, such as charge, hydrophobicity, specific binding interactions, or movement in an electrical field. The separated fractions are detected by means of the ISE(s). These ISEs can be used singly or in an array. Accordingly, modifications in the ISEs are used to permit detection of low activities, specifically, below 10.sup.-6 M, by using low activities of the primary analyte (the molecular species which is specifically detected) in the inner filling solution of the ISE. Arrays constructed in various ways allow flow-through sensing for multiple ions.

  5. EPR of uranium ions

    International Nuclear Information System (INIS)

    Ursu, I.; Lupei, V.

    1984-02-01

    A review of the electron paramagnetic resonance data on the uranium ions is given. After a general account of the electronic structure of the uranium free atoms and ions, the influence of the external fields (magnetic field, crystal fields) is discussed. The main information obtained from EPR studies on the uranium ions in crystals are emphasized: identification of the valence and of the ground electronic state, determination of the structure of the centers, crystal field effects, role of the intermediate coupling and of the J-mixing, role of the covalency, determination of the nuclear spin, maqnetic dipole moment and electric quadrupole moment of the odd isotopes of uranium. These data emphasize the fact that the actinide group has its own identity and this is accutely manifested at the beginning of the 5fsup(n) series encompassed by the uranium ions. (authors)

  6. Trapping radioactive ions

    International Nuclear Information System (INIS)

    Kluge, H.-J.; Blaum, K.

    2004-01-01

    Trapping devices for atomic and nuclear physics experiments with radioactive ions are becoming more and more important at accelerator facilities. While about ten years ago only one online Penning trap experiment existed, namely ISOLTRAP at ISOLDE/CERN, meanwhile almost every radioactive beam facility has installed or plans an ion trap setup. This article gives an overview on ion traps in the operation, construction or planing phase which will be used for fundamental studies with short-lived radioactive nuclides such as mass spectrometry, laser spectroscopy and nuclear decay spectroscopy. In addition, this article summarizes the use of gas cells and radiofrequency quadrupole (Paul) traps at different facilities as a versatile tool for ion beam manipulation like retardation, cooling, bunching, and cleaning

  7. Ion - biomolecule interactions and radiation damage

    International Nuclear Information System (INIS)

    Schlathoelter, T.

    2004-01-01

    fragmentation cross sections as well as kinetic energies of the various primary and secondary species. An important aspect of the current research in this field focuses on collisions of keV (singly and multiply charged) ions with molecules such as water [1,3] and DNA building blocks [2,3,4]. These energies are typical for slowed down heavy ions or protons in the Bragg peak region. Relative and absolute cross sections as well as fragment kinetic energies are measured by means of coincidence time-of-flight spectrometry or fragment ion spectroscopy. Fragment ion kinetic energies exceeding 10 eV are observed in these studies. Recent data on interaction of very low energy ions (0.5 eV - 500 eV) with solid nucleobases showed that ion kinetic energies of less than 5 eV are still sufficient to induce substantial fragmentation [5]. This implies that in the vicinity of a DNA strand break induced by a primary ion, fragment ions migh induce further damage, possibly double strand breaks or clustered lesions. Such biological damage can also be assessed on a larger scale: Ion irradiation of e.g. supported plasmid DNA and subsequent investigation by gel electrophoresis [6] or atomic force microscopy allows quantitative studies of the induced single and double strand breaks

  8. Ion exchange equilibrium constants

    CERN Document Server

    Marcus, Y

    2013-01-01

    Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and

  9. Heavy ion accelerators

    International Nuclear Information System (INIS)

    Schmelzer, C.

    1974-01-01

    This review of the present state of work on heavy-ion accelerators pays particular attention to the requirements for nuclear research. It is divided into the following sections: single-particle versus collective acceleration, heavy-ion accelerators, beam quality, and a status report on the UNILAC facility. Among the topics considered are the recycling cyclotron, linacs with superconducting resonators, and acceleration to the GeV/nucleon range. (8 figures, 2 tables) (U.S.)

  10. Ion Mass Determination

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (100) is described for determining the mass of ions, the apparatus configured to hold a plasma (101 ) having a plasma potential. The apparatus (100) comprises an electrode (102) having a surface extending in a surface plane and an insulator (104) interfacing with the electrode (102......, and a processing unit (108) configured to interpret the detected impact locations in terms of the mass of the impacting ions....

  11. Ion beam diagnosis

    International Nuclear Information System (INIS)

    Strehl, P.

    1994-04-01

    This report is an introduction to ion beam diagnosis. After a short description of the most important ion beam parameters measurements of the beam current by means of Faraday cups, calorimetry, and beam current transformers and measurements of the beam profile by means of viewing screens, profile grids and scanning devices, and residual gas ionization monitors are described. Finally measurements in the transverse and longitudinal phase space are considered. (HSI)

  12. Ion implantation - an introduction

    International Nuclear Information System (INIS)

    Townsend, P.D.

    1986-01-01

    Ion implantation is a widely used technique with a literature that covers semiconductor production, surface treatments of steels, corrosion resistance, catalysis and integrated optics. This brief introduction outlines advantages of the technique, some aspects of the underlying physics and examples of current applications. Ion implantation is already an essential part of semiconductor technology while in many other areas it is still in an early stage of development. The future scope of the subject is discussed. (author)

  13. Aspirated capacitor measurements of air conductivity and ion mobility spectra

    International Nuclear Information System (INIS)

    Aplin, K.L.

    2005-01-01

    Measurements of ions in atmospheric air are used to investigate atmospheric electricity and particulate pollution. Commonly studied ion parameters are (1) air conductivity, related to the total ion number concentration, and (2) the ion mobility spectrum, which varies with atmospheric composition. The physical principles of air ion instrumentation are long established. A recent development is the computerized aspirated capacitor, which measures ions from (a) the current of charged particles at a sensing electrode, and (b) the rate of charge exchange with an electrode at a known initial potential, relaxing to a lower potential. As the voltage decays, only ions of higher and higher mobility are collected by the central electrode and contribute to the further decay of the voltage. This enables extension of the classical theory to calculate ion mobility spectra by inverting voltage decay time series. In indoor air, ion mobility spectra determined from both the voltage decay inversion, and an established voltage switching technique, were compared and shown to be of similar shape. Air conductivities calculated by integration were: 5.3±2.5 and 2.7±1.1 fSm -1 , respectively, with conductivity determined to be 3 fSm -1 by direct measurement at a constant voltage. Applications of the relaxation potential inversion method include air ion mobility spectrum retrieval from historical data, and computation of ion mobility spectra in planetary atmospheres

  14. 2010 ion run: completed!

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    After a very fast switchover from protons to lead ions, the LHC has achieved performances that allowed the machine to exceed both peak and integrated luminosity by a factor of three. Thanks to this, experiments have been able to produce high-profile results on ion physics almost immediately, confirming that the LHC was able to keep its promises for ions as well as for protons.   First direct observation of jet quenching. A seminar on 2 December was the opportunity for the ALICE, ATLAS and CMS collaborations to present their first results on ion physics in front of a packed auditorium. These results are important and are already having a major impact on the understanding of the physics processes that involve the basic constituents of matter at high energies. In the ion-ion collisions, the temperature is so high that partons (quarks and gluons), which are usually constrained inside the nucleons, are deconfined to form a highly dense and hot soup known as quark-gluon plasma (QGP). The existence of ...

  15. Collective focusing ion accelerator

    International Nuclear Information System (INIS)

    Goldin, F.J.

    1986-01-01

    The principal subject of this dissertation is the trapping confinement of pure electron plasmas in bumpy toroidal magnetic fields, with particular attention given to the trapping procedure and the behavior of the plasma during the final equilibrium. The most important aspects of the equilibrium studied were the qualitative nature of the plasma configuration and motion and its density, distribution and stability. The motivation for this study was that an unneutralized cloud of electrons contained in a toroidal system, sufficiently dense and stable, may serve to electrostatically focus ions (against centrifugal and self space charge forces) in a cyclic ion accelerator. Such an accelerator, known as a Collective Focusing Ion Accelerator (CFIA) could be far smaller than conventional designs (which use external magnetic fields directly to focus the ions) due to the smaller gyro-radium of an electron in a magnetic field of given strength. The electron cloud generally drifted poloidally at a finite radius from the toroidal minor axis. As this would preclude focusing ions with such clouds, damping this motion was investigated. Finite resistance in the normally perfectly conductive vessel wall did this. In further preparation for a working CFIA, additional experiments studied the effect of ions on the stability of the electron cloud

  16. Ion bombardment and disorder in amorphous silicon

    International Nuclear Information System (INIS)

    Sidhu, L.S.; Gaspari, F.; Zukotynski, S.

    1997-01-01

    The effect of ion bombardment during growth on the structural and optical properties of amorphous silicon are presented. Two series of films were deposited under electrically grounded and positively biased substrate conditions. The biased samples displayed lower growth rates and increased hydrogen content relative to grounded counterparts. The film structure was examined using Raman spectroscopy. The transverse optic like phonon band position was used as a parameter to characterize network order. Biased samples displayed an increased order of the amorphous network relative to grounded samples. Furthermore, biased samples exhibited a larger optical gap. These results are correlated and attributed to reduced ion bombardment effects

  17. Ion mixing and numerical simulation of different ions produced in the ECR ion source

    International Nuclear Information System (INIS)

    Shirkov, G.D.

    1996-01-01

    This paper is to continue theoretical investigations and numerical simulations in the physics of ECR ion sources within the CERN program on heavy ion acceleration. The gas (ion) mixing effect in ECR sources is considered here. It is shown that the addition of light ions to the ECR plasma has three different mechanisms to improve highly charged ion production: the increase of confinement time and charge state of highly ions as the result of ion cooling; the concentration of highly charged ions in the central region of the source with high energy and density of electrons; the increase of electron production rate and density of plasma. The numerical simulations of lead ion production in the mixture with different light ions and different heavy and intermediate ions in the mixture with oxygen, are carried out to predict the principal ECR source possibilities for LHC applications. 18 refs., 23 refs

  18. Performance of the K+ ion diode in the 2 MV injector for heavy ion fusion

    Science.gov (United States)

    Bieniosek, F. M.; Henestroza, E.; Kwan, J. W.

    2002-02-01

    Heavy ion beam inertial fusion driver concepts depend on the availability and performance of high-brightness high-current ion sources. Surface ionization sources have relatively low current density but high brightness because of the low temperature of the emitted ions. We have measured the beam profiles at the exit of the injector diode, and compared the measured profiles with EGUN and WARP-3D predictions. Spherical aberrations are significant in this large aspect ratio diode. We discuss the measured and calculated beam size and beam profiles, the effect of aberrations, quality of vacuum, and secondary electron distributions on the beam profile.

  19. Materials analysis by ion backscattering and channeling. Materials modification by ion irradiation and implementation

    International Nuclear Information System (INIS)

    Meyer, O.

    1984-08-01

    A description will be given of the basic processes occuring during ion implantation and ion beam analyses. The usefulness of the backscattering and channeling technique is demonstrated by a discussion of the applications to thin film analysis, studies of diffusion and reactions in thin films, lattice location investigations, disorder analysis and surface studies. Ion implantation is a valuable research tool in metallurgy. The process operates very far from equilibrium conditions and thus will influence near surface properties in a unique way. The observed modifications are related to special microscopic structures which will be considered in detail. (orig.) [de

  20. Consideration of beam plasma ion-source

    International Nuclear Information System (INIS)

    Sano, Fumimichi; Kusano, Norimasa; Ishida, Yoshihiro; Ishikawa, Junzo; Takagi, Toshinori

    1976-01-01

    Theoretical and experimental analyses and their comparison were made on the plasma generation and on the beam extraction for the beam plasma ion-source. The operational principle and the structure of the ion-source are explained in the first part. Considerations are given on the electron beam-plasma interaction and the resulting generation of high frequency or microwaves which in turn increases the plasma density. The flow of energy in this system is also explained in the second part. The relation between plasma density and the imaginary part of frequency is given by taking the magnetic flux density, the electron beam energy, and the electron beam current as parameters. The relations between the potential difference between collector and drift tube and the plasma density or the ion-current are also given. Considerations are also given to the change of the plasma density due to the change of the magnetic flux density at drift tube, the change of the electron beam energy, and the change of the electron beam current. The third part deals with the extraction characteristics of the ion beam. The structure of the multiple-aperture electrode and the relation between plasma density and the extracted ion current are explained. (Aoki, K.)

  1. Biomaterials modification by ion beam

    International Nuclear Information System (INIS)

    Zhang Tonghe; Yi Zhongzhen; Zhang Xu; Wu Yuguang

    2001-01-01

    Ion beam technology is one of best ways for the modification of biomaterials. The results of ion beam modification of biomaterials are given. The method and results of improved biocompatibility are indicated by ion beam technology. The future development of ion beam modification of biomaterials is discussed

  2. Light-induced ion-acoustic instability of rarefied plasma

    International Nuclear Information System (INIS)

    Krasnov, I.V.; Sizykh, D.V.

    1987-01-01

    A new method of ion-acoustic instability excitation under the effect of coherent light, resonance to ion quantum transitions on collisionless plasma, is suggested. The light-induced ion-acoustic instability (LIIAI) considered is based on the induced progressive nonequilibrium resonance particles in the field of travelling electromagnetic wave. Principal possibility to use LIIAI in high-resolution spectroscopy and in applied problems of plasma physics, related to its instability, is pointed out

  3. Gas-phase ion/ion reactions of peptides and proteins: acid/base, redox, and covalent chemistries.

    Science.gov (United States)

    Prentice, Boone M; McLuckey, Scott A

    2013-02-01

    Gas-phase ion/ion reactions are emerging as useful and flexible means for the manipulation and characterization of peptide and protein biopolymers. Acid/base-like chemical reactions (i.e., proton transfer reactions) and reduction/oxidation (redox) reactions (i.e., electron transfer reactions) represent relatively mature classes of gas-phase chemical reactions. Even so, especially in regards to redox chemistry, the widespread utility of these two types of chemistries is undergoing rapid growth and development. Additionally, a relatively new class of gas-phase ion/ion transformations is emerging which involves the selective formation of functional-group-specific covalent bonds. This feature details our current work and perspective on the developments and current capabilities of these three areas of ion/ion chemistry with an eye towards possible future directions of the field.

  4. Ball lightning dynamics and stability at moderate ion densities

    International Nuclear Information System (INIS)

    Morrow, R

    2017-01-01

    A general mechanism is presented for the dynamics and structure of ball lightning and for the maintenance of the ball lightning structure for several seconds. Results are obtained using a spherical geometry for air at atmospheric pressure, by solving the continuity equations for electrons, positive ions and negative ions coupled with Poisson’s equation. A lightning strike can generate conditions in the lightning channel with a majority of positive nitrogen ions, and a minority of negative oxygen ions and electrons. The calculations are initiated with electrons included; however, at the moderate ion densities chosen the electrons are rapidly lost to form negative ions, and after 1 µ s their influence on the ion dynamics is negligible. Further development after 1 µ s is followed using a simpler set of equations involving only positive ions and negative ions, but including ion diffusion. The space-charge electric field generated by the majority positive ions drives them from the centre of the distribution and drives the minority negative ions and electrons towards the centre of the distribution. In the central region the positive and negative ion distributions eventually overlap exactly and their space-charge fields cancel resulting in zero electric field, and the plasma ball formed is quite stable for a number of seconds. The formation of such plasma balls is not critically dependent on the initial diameter of the ion distributions, or the initial density of minority negative ions. The ion densities decrease relatively slowly due to mutual neutralization of positive and negative ions. The radiation from this neutralization process involving positive nitrogen ions and negative oxygen ions is not sufficient to account for the reported luminosity of ball lightning and some other source of luminosity is shown to be required; the plasma ball model used could readily incorporate other ions in order to account for the luminosity and range of colours reported for ball

  5. Ion-selective electrode reviews

    CERN Document Server

    Thomas, J D R

    1983-01-01

    Ion-Selective Electrode Reviews, Volume 5 is a collection of articles that covers ion-speciation. The book aims to present the advancements of the range and capabilities of selective ion-sensors. The topics covered in the selection are neutral carrier based ion-selective electrodes; reference electrodes and liquid junction effects in ion-selective electrode potentiometry; ion transfer across water/organic phase boundaries and analytical; and carbon substrate ion-selective electrodes. The text will be of great use to chemists and chemical engineers.

  6. Ion optics of RHIC EBIS

    Energy Technology Data Exchange (ETDEWEB)

    Pikin, A.; Alessi, J.; Beebe, E.; Kponou, A.; Okamura, M.; Raparia, D.; Ritter, J.; Tan, Y.; Kuznetsov, G.

    2011-09-10

    RHIC EBIS has been commissioned to operate as a versatile ion source on RHIC injection facility supplying ion species from He to Au for Booster. Except for light gaseous elements RHIC EBIS employs ion injection from several external primary ion sources. With electrostatic optics fast switching from one ion species to another can be done on a pulse to pulse mode. The design of an ion optical structure and the results of simulations for different ion species are presented. In the choice of optical elements special attention was paid to spherical aberrations for high-current space charge dominated ion beams. The combination of a gridded lens and a magnet lens in LEBT provides flexibility of optical control for a wide range of ion species to satisfy acceptance parameters of RFQ. The results of ion transmission measurements are presented.

  7. Ion-Responsive Drug Delivery Systems.

    Science.gov (United States)

    Yoshida, Takayuki; Shakushiro, Kohsuke; Sako, Kazuhiro

    2018-02-08

    Some kinds of cations and anions are contained in body fluids such as blood, interstitial fluid, gastrointestinal juice, and tears at relatively high concentration. Ionresponsive drug delivery is available to design the unique dosage formulations which provide optimized drug therapy with effective, safe and convenient dosing of drugs. The objective of the present review was to collect, summarize, and categorize recent research findings on ion-responsive drug delivery systems. Ions in body fluid/formulations caused structural changes of polymers/molecules contained in the formulations, allow formulations exhibit functions. The polymers/molecules responding to ions were ion-exchange resins/fibers, anionic or cationic polymers, polymers exhibiting transition at lower critical solution temperature, self-assemble supramolecular systems, peptides, and metalorganic frameworks. The functions of ion-responsive drug delivery systems were categorized to controlled drug release, site-specific drug release, in situ gelation, prolonged retention at the target sites, and enhancement of drug permeation. Administration of the formulations via oral, ophthalmic, transdermal, and nasal routes has showed significant advantages in the recent literatures. Many kinds of drug delivery systems responding to ions have been reported recently for several administration routes. Improvement and advancement of these systems can maximize drugs potential and contribute to patients in the world. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Ion acoustic waves in the solar wind

    International Nuclear Information System (INIS)

    Gurnett, D.A.; Frank, L.A.

    1978-01-01

    Plasma wave measurements on the Helios I and 2 spacecraft have revealed the occurrence of electric field turbulence in the solar wind at frequencies between the electron and ion plasma frequencies. Wavelength measurements with the Imp 6 spacecraft now provide strong evidence that these waves are short-wavelength ion acoustic waves which are Doppler-shifted upward in frequency by the motion of the solar wind. Comparison of the Helios results with measurements from the earth-orbiting Imp 6 and 8 spacecraft shows that the ion acoustic turbulence detected in interplanetary space has characteristics essentially identical to those of bursts of electrostatic turbulence generated by protons streaming into the solar wind from the earth's bow shock. In a few cases, enhanced ion acoustic wave intensities have been observed in direct association with abrupt increases in the anisotropy of the solar wind electron distribution. This relationship strongly suggests that the ion acoustic waves detected by Helios far from the earth are produced by an electron heat flux instability, as was suggested by Forslund. Possible related mechanisms which could explain the generation of ion acoustic waves by protons streaming into the solar wind from the earth's bow shock are also considered

  9. Solar-wind minor ions: recent observations

    International Nuclear Information System (INIS)

    Bame, S.J.

    1982-01-01

    During the years following the Solar Wind Four Conference at Burghausen our knowledge of the solar wind ion composition and dynamics has grown. There have been some surprises, and our understanding of the evolution of the solar wind has been improved. Systematic studies have shown that the minor ions generally travel with a common bulk speed and have temperatures roughly proportional to their masses. It has been determined that the 3 He ++ content varies greatly; 3 He ++ / 4 He ++ ranges from as high as 10 2 values to below 2 x 10 - 4 . In some solar wind flows which can be related to energetic coronal events, the minor ions are found in unusual ionization states containing Fe 16 + as a prominent ion, showing that the states were formed at unusually high temperatures. Unexpectedly, in a few flows substantial quantities of 4 He + have been detected, sometimes with ions identifiable as O 2 + and O 3 + . Surprisingly, in some of these examples the ionization state is mixed showing that part of the plasma escaped the corona without attaining the usual million-degree temperatures while other parts were heated more nearly in the normal manner. Additionally, detailed studies of the minor ions have increased our understanding of the coronal expansion. For example, such studies have contributed to identifying near equatorial coronal streamers as the source of solar wind flows between high speed streams

  10. Ion beam inertial fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1995-01-01

    About twenty years ago, A. W. Maschke of Brookhaven National Laboratory and R. L. Martin of Argonne National Laboratory recognized that the accelerators that have been developed for high energy and nuclear physics are, in many ways, ideally suited to the requirements of inertial fusion power production. These accelerators are reliable, they have a long operating life, and they can be efficient. Maschke and Martin noted that they can focus ion beams to small focal spots over distances of many meters and that they can readily operate at the high pulse repetition rates needed for commercial power production. Fusion, however, does impose some important new constraints that are not important for high energy or nuclear physics applications. The most challenging new constraint from a scientific standpoint is the requirement that the accelerator deliver more than 10 14 W of beam power to a small quantity (less than 100 mg) of matter. The most challenging constraint from an engineering standpoint is accelerator cost. Maschke showed theoretically that accelerators could produce adequate work. Heavy-ion fusion is widely recognized to be a promising approach to inertial fusion power production. It provides an excellent opportunity to apply methods and technology developed for basic science to an important societal need. The pulsed-power community has developed a complementary, parallel approach to ion beam fusion known as light-ion fusion. The talk will discuss both heavy-ion and light-ion fusion. It will explain target physics requirements and show how they lead to constraints on the usual accelerator parameters such as kinetic energy, current, and emittance. The talk will discuss experiments that are presently underway, specifically experiments on high-current ion sources and injectors, pulsed-power machines recirculating induction accelerators, and transverse beam combining. The talk will give a brief description of a proposed new accelerator called Elise

  11. Ion-selective electrode reviews

    CERN Document Server

    Thomas, J D R

    1985-01-01

    Ion-Selective Electrode Reviews, Volume 7 is a collection of papers that covers the applications of electrochemical sensors, along with the versatility of ion-selective electrodes. The coverage of the text includes solid contact in membrane ion-selective electrodes; immobilized enzyme probes for determining inhibitors; potentiometric titrations based on ion-pair formation; and application of ion-selective electrodes in soil science, kinetics, and kinetic analysis. The text will be of great use to chemists and chemical engineers.

  12. Clues From Pluto's Ions

    Science.gov (United States)

    Kohler, Susanna

    2016-05-01

    Nearly a year ago, in July 2015, the New Horizons spacecraft passed by the Pluto system. The wealth of data amassed from that flyby is still being analyzed including data from the Solar Wind Around Pluto (SWAP) instrument. Recent examination of this data has revealedinteresting new information about Plutos atmosphere and how the solar wind interacts with it.A Heavy Ion TailThe solar wind is a constant stream of charged particles released by the Sun at speeds of around 400 km/s (thats 1 million mph!). This wind travels out to the far reaches of the solar system, interacting with the bodies it encounters along the way.By modeling the SWAP detections, the authors determine the directions of the IMF that could produce the heavy ions detected. Red pixels represent IMF directions permitted. No possible IMF could reproduce the detections if the ions are nitrogen (bottom panels), and only retrograde IMF directions can produce the detections if the ions are methane. [Adapted from Zirnstein et al. 2016]New Horizons data has revealed that Plutos atmosphere leaks neutral nitrogen, methane, and carbon monoxide molecules that sometimes escape its weak gravitational pull. These molecules become ionized and are subsequently picked up by the passing solar wind, forming a tail of heavy ions behind Pluto. The details of the geometry and composition of this tail, however, had not yet been determined.Escaping MethaneIn a recent study led by Eric Zirnstein (Southwest Research Institute), the latest analysis of data from the SWAP instrument on board New Horizons is reported. The team used SWAPs ion detections from just after New Horizons closest approach to Pluto to better understand how the heavy ions around Pluto behave, and how the solar wind interacts with Plutos atmosphere.In the process of analyzing the SWAP data, Zirnstein and collaborators first establish what the majority of the heavy ions picked up by the solar wind are. Models of the SWAP detections indicate they are unlikely

  13. Study of ion exchange equilibrium and determination of heat of ion exchange by ion chromatography

    International Nuclear Information System (INIS)

    Liu Kailu; Yang Wenying

    1996-01-01

    Ion chromatography using pellicularia ion exchange resins and dilute solution can be devoted to the study of ion exchange thermodynamics and kinetics. Ion exchange equilibrium equation was obtained, and examined by the experiments. Based on ion exchange equilibrium, the influence of eluent concentration and resin capacity on adjusted retention volumes was examined. The effect of temperature on adjusted retention volumes was investigated and heats of ion exchange of seven anions were determined by ion chromatography. The interaction between anions and skeleton structure of resins were observed

  14. The ion circus

    Energy Technology Data Exchange (ETDEWEB)

    Minaya Ramirez, Enrique [GSI Helmholtzzentrum, Darmstadt (Germany); Lunney, David [CSNSM- IN2P3/CNRS, Universite de Paris-Sud, Orsay (France)

    2010-07-01

    The ability to prepare radioactive beams for experiments in nuclear structure has seen important developments in recent years. The use of ion traps and buffer-gas cooling now enables the accumulation and purification of even short-lived nuclides. This is a key point for future installations since higher intensity also brings increased isobaric contamination which can be disastrous for background. Until now, the development of beam cooler/bunchers has relied on linear (radiofrequency quadrupole) Paul traps. In this contribution we describe the progress in developing a novel circular Paul trap. The ion circus, so named for its ability to trap ions at different positions along the ring circumference and to eject them in either perpendicular or tangential direction, has also been designed to cool and mass separate the ions over a longer flight path. The resolving power is increased as the ions orbit in the ring and are cooled with buffer gas at a much lower pressure. The first prototype is now under test in Orsay. We report results of the first tests and the future program.

  15. Inverted magnetron ion source

    International Nuclear Information System (INIS)

    Singh, B.; Boyarsky, D.

    1985-01-01

    The present invention provides, in a preferred embodiment, a cylindrical stainless steel cathode with end pieces thereon to form a cathode chamber within. In addition, in a preferred embodiment, there is a stainless steel rod which passes axially through the cathode chamber and which is electrically insulated therefrom at the end pieces. The stainless steel cathode has first and second apertures formed therein with the first to be connected to a source of ionizable gas and the second to act as the opening through which there passes a stream of ions to an ion beam target. A magnetic flux source is coupled to the cathode chamber to pass magnetic flux therethrough and a voltage source is connected between the anode and the cathode to provide an electrostatic field therebetween whereby when ionizable gas is fed into the cathode chamber, it is ionized and a stream of ions emanates from the second aperture. In a preferred embodiment there is further provided an electrostatic ion focusing means to focus the ion stream emanating from the second aperture

  16. Neurosurgical applications of ion beams

    Science.gov (United States)

    Fabrikant, Jacob I.; Levy, Richard P.; Phillips, Mark H.; Frankel, Kenneth A.; Lyman, John T.

    1989-04-01

    The program at Donner Pavilion has applied nuclear medicine research to the diagnosis and radiosurgical treatment of life-threatening intracranial vascular disorders that affect more than half a million Americans. Stereotactic heavy-charged-particle Bragg peak radiosurgery, using narrow beams of heavy ions, demonstrates superior biological and physical characteristics in brain over X-and γ-rays, viz., improved dose distribution in the Bragg peak and sharp lateral and distal borders and less scattering of the beam. Examination of CNS tissue response and alteration of cerebral blood-flow dynamics related to heavy-ion Bragg peak radiosurgery is carried out using three-dimensional treatment planning and quantitative imaging utilizing cerebral angiography, computerized tomography (CT), magnetic resonance imaging (MRI), cine-CT, xenon X-ray CT and positron emission tomography (PET). Also under examination are the physical properties of narrow heavy-ion beams for improving methods of dose delivery and dose distribution and for establishing clinical RBE/LET and dose-response relationships for human CNS tissues. Based on the evaluation and treatment with stereotactically directed narrow beams of heavy charged particles of over 300 patients, with cerebral angiography, CT scanning and MRI and PET scanning of selected patients, plus extensive clinical and neuroradiological followup, it appears that Stereotactic charged-particle Bragg peak radiosurgery obliterates intracranial arteriovenous malformations or protects against rebleeding with reduced morbidity and no mortality. Discussion will include the method of evaluation, the clinical research protocol, the Stereotactic neuroradiological preparation, treatment planning, the radiosurgery procedure and the protocol for followup. Emphasis will be placed on the neurological results, including the neuroradiological and clinical response and early and late delayed injury in brain leading to complications (including vasogenic edema

  17. Atmospheric ions and nucleation: a review of observations

    Directory of Open Access Journals (Sweden)

    A. Hirsikko

    2011-01-01

    Full Text Available This review is based on ca. 260 publications, 93 of which included data on the temporal and spatial variation of the concentration of small ions (<1.6 nm in diameter especially in the lower troposphere, chemical composition, or formation and growth rates of sub-3 nm ions. This information was collected on tables and figures. The small ions exist all the time in the atmosphere, and the average concentrations of positive and negative small ions are typically 200–2500 cm−3. However, concentrations up to 5000 cm−3 have been observed. The results are in agreement with observations of ion production rates in the atmosphere. We also summarised observations on the conversion of small ions to intermediate ions, which can act as embryos for new atmospheric aerosol particles. Those observations include the formation rates (J2[ion] of 2-nm intermediate ions, growth rates (GR[ion] of sub-3 nm ions, and information on the chemical composition of the ions. Unfortunately, there were only a few studies which presented J2[ion] and GR[ion]. Based on the publications, the formation rates of 2-nm ions were 0–1.1 cm−3 s−1, while the total 2-nm particle formation rates varied between 0.001 and 60 cm−3 s−1. Due to small changes in J2[ion], the relative importance of ions in 2-nm particle formation was determined by the large changes in J2[tot], and, accordingly the contribution of ions increased with decreasing J2[tot]. Furthermore, small ions were observed to activate for growth earlier than neutral nanometer-sized particles and at lower saturation ratio of condensing vapours.

  18. Majority ion heating near the ion-ion hybrid layer in tokamaks

    International Nuclear Information System (INIS)

    Phillips, C.K.; Hosea, J.C.; Ignat, D.; Majeski, R.; Rogers, J.H.; Schilling, G.; Wilson, J.R.

    1995-08-01

    Efficient direct majority ion heating in a deuterium-tritium (D-T) reactor-grade plasma via absorption of fast magnetosonic waves in the ion cyclotron range of frequencies (ICRF) is discussed. Majority ion heating results from resonance overlap between the cyclotron layers and the D-T ion-ion hybrid layer in hot, dense plasmas for fast waves launched with high parallel wavenumbers. Analytic and numerical models are used to explore the regime in ITER plasmas

  19. Empirical stopping powers for ions in solids

    International Nuclear Information System (INIS)

    Ziegler, J.F.; Biersack, J.P.; Littmark, U.

    1983-01-01

    The work of Brandt and collaborators on low energy ion stopping powers has been extended to create an empirical formulation for the stopping of ions in solids. The result is a simple computer program (about 60 lines of code) which calculates stopping powers from zero to 100 MeV/amu for all ions in all elemental solids. This code has been compared to the data in about 2000 papers, and has a standard error of 9% for energies above keV/amu. This approach includes high energy relativistic effects and shell-corrections. In the medium energy range it uses stopping theory based on the local-density approximation and Lindhard stopping in a free electron gas. This is applied to realistic Hartree-Fock charge distributions for crystalline solids. In the low energy range it uses the Brandt concepts of ion stripping relative to the Fermi velocity of solids, and also his formalism for the relation of projectile ionization to its effective charge. The details of the calculation are presented, and a broad comparison is shown with experiment. Special comparative examples are shown of both the low energy stopping power oscillations which depend on the atomic number of the ion, and also of the target

  20. The Function of the Novel Mechanical Activated Ion Channel Piezo1 in the Human Osteosarcoma Cells

    OpenAIRE

    Jiang, Long; Zhao, Yi-ding; Chen, Wei-xiang

    2017-01-01

    Background The Piezo1 protein ion channel is a novel mechanical activated ion channel which is related to mechanical signal transduction. However, the function of the mechanically activated ion channel Piezo1 had not been explored. In this study, we explored the function of the Piezo1 ion channel in human osteosarcoma (OS) cells related to apoptosis, invasion, and the cell proliferation. Material/Methods Reverse transcription polymerase chain reaction (RT-PCR) and western-blotting were used t...

  1. Ion channels versus ion pumps: the principal difference, in principle.

    Science.gov (United States)

    Gadsby, David C

    2009-05-01

    The incessant traffic of ions across cell membranes is controlled by two kinds of border guards: ion channels and ion pumps. Open channels let selected ions diffuse rapidly down electrical and concentration gradients, whereas ion pumps labour tirelessly to maintain the gradients by consuming energy to slowly move ions thermodynamically uphill. Because of the diametrically opposed tasks and the divergent speeds of channels and pumps, they have traditionally been viewed as completely different entities, as alike as chalk and cheese. But new structural and mechanistic information about both of these classes of molecular machines challenges this comfortable separation and forces its re-evaluation.

  2. Three-dimensional simulation of the electromagnetic ion/ion beam instability: cross field diffusion

    Directory of Open Access Journals (Sweden)

    H. Kucharek

    2000-01-01

    Full Text Available In a system with at least one ignorable spatial dimension charged particles moving in fluctuating fields are tied to the magnetic field lines. Thus, in one-and two-dimensional simulations cross-field diffusion is inhibited and important physics may be lost. We have investigated cross-field diffusion in self-consistent 3-D magnetic turbulence by fully 3-dimensional hybrid simulation (macro-particle ions, massless electron fluid. The turbulence is generated by the electromagnetic ion/ion beam instability. A cold, low density, ion beam with a high velocity stream relative to the background plasma excites the right-hand resonant instability. Such ion beams may be important in the region of the Earth's foreshock. The field turbulence scatters the beam ions parallel as well as perpendicular to the magnetic field. We have determined the parallel and perpendicular diffusion coefficient for the beam ions in the turbulent wave field. The result compares favourably well (within a factor 2 with hard-sphere scattering theory for the cross-field diffusion coefficient. The cross-field diffusion coefficient is larger than that obtained in a static field with a Kolmogorov type spectrum and similar total fluctuation power. This is attributed to the resonant behaviour of the particles in the fluctuating field.

  3. Development of a beam ion velocity detector for the heavy ion beam probe

    Energy Technology Data Exchange (ETDEWEB)

    Fimognari, P. J., E-mail: PJFimognari@XanthoTechnologies.com; Crowley, T. P.; Demers, D. R. [Xantho Technologies, LLC, Madison, Wisconsin 53705 (United States)

    2016-11-15

    In an axisymmetric plasma, the conservation of canonical angular momentum constrains heavy ion beam probe (HIBP) trajectories such that measurement of the toroidal velocity component of secondary ions provides a localized determination of the poloidal flux at the volume where they originated. We have developed a prototype detector which is designed to determine the beam angle in one dimension through the detection of ion current landing on two parallel planes of detecting elements. A set of apertures creates a pattern of ion current on wires in the first plane and solid metal plates behind them; the relative amounts detected by the wires and plates determine the angle which beam ions enter the detector, which is used to infer the toroidal velocity component. The design evolved from a series of simulations within which we modeled ion beam velocity changes due to equilibrium and fluctuating magnetic fields, along with the ion beam profile and velocity dispersion, and studied how these and characteristics such as the size, cross section, and spacing of the detector elements affect performance.

  4. Development of a beam ion velocity detector for the heavy ion beam probe

    International Nuclear Information System (INIS)

    Fimognari, P. J.; Crowley, T. P.; Demers, D. R.

    2016-01-01

    In an axisymmetric plasma, the conservation of canonical angular momentum constrains heavy ion beam probe (HIBP) trajectories such that measurement of the toroidal velocity component of secondary ions provides a localized determination of the poloidal flux at the volume where they originated. We have developed a prototype detector which is designed to determine the beam angle in one dimension through the detection of ion current landing on two parallel planes of detecting elements. A set of apertures creates a pattern of ion current on wires in the first plane and solid metal plates behind them; the relative amounts detected by the wires and plates determine the angle which beam ions enter the detector, which is used to infer the toroidal velocity component. The design evolved from a series of simulations within which we modeled ion beam velocity changes due to equilibrium and fluctuating magnetic fields, along with the ion beam profile and velocity dispersion, and studied how these and characteristics such as the size, cross section, and spacing of the detector elements affect performance.

  5. Heavy-ion radiography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.

    1981-01-01

    Heavy-particle radiography has clinical potential as a newly developed noninvasive low-dose imaging procedure that provides increased resolution of minute density differences in soft tissues of the body. The method utilizes accelerated high-energy ions, primarily carbon and neon, at the Bevalac accelerator at the Lawrence Berkeley Laboratory. The research program for medicine utilizes heavy-ion radiography for low-dose mammography, for treatment planning for cancer patients, and for imaging and accurate densitometry of skeletal structures, brain and spinal neoplasms, and the heart. The potential of heavy-ion imaging, and particularly reconstruction tomography, is now proving to be an adjunct to existing diagnostic imaging procedures in medicine, both for applications to the diagnosis, management and treatment of clinical cancer in man, and for the early detection of small soft-tissue tumors at low radiation dose

  6. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Keefe, D.; Sessler, A.M.

    1980-01-01

    Inertial fusion has not yet been as well explored as magnetic fusion but can offer certain advantages as an alternative source of electric energy for the future. Present experiments use high-power beams from lasers and light-ion diodes to compress the deuterium-tritium (D-T) pellets but these will probably be unsuitable for a power plant. A more promising method is to use intense heavy-ion beams from accelerator systems similar to those used for nuclear and high-energy physics; the present paper addresses itself to this alternative. As will be demonstrated the very high beam power needed poses new design questions, from the ion-source through the accelerating system, the beam transport system, to the final focus. These problems will require extensive study, both theoretically and experimentally, over the next several years before an optimum design for an inertial fusion driver can be arrived at. (Auth.)

  7. Acceleration of radioactive ions

    International Nuclear Information System (INIS)

    Laxdal, R.E.

    2003-01-01

    There is an intense interest world-wide in the use of radioactive ion beams (RIBs) for experiment. In many existing or proposed facilities ions are produced or collected at source potential, ionized and re-accelerated. Within the past year three new ISOL based facilities have added dedicated post-accelerators to deliver accelerated RIBs to experiment. The paper gives an overview of RIB accelerators present and future, and explores the inherent features in the various acceleration methods with an emphasis on heavy ion linacs. The ISAC-I and ISAC-II post-accelerators are discussed as examples. Commissioning results and initial operating experience with ISAC-I will be presented

  8. Ion accelerators for space

    International Nuclear Information System (INIS)

    Slobodrian, R.J.; Potvin, L.

    1991-01-01

    The main purpose of the accelerators is to allow ion implantation in space stations and their neighborhoods. There are several applications of interest immediately useful in such environment: as ion engines and thrusters, as implanters for material science and for hardening of surfaces (relevant to improve resistance to micrometeorite bombardment of exposed external components), production of man made alloys, etc. The microgravity environment of space stations allows the production of substances (crystalline and amorphous) under conditions unknown on earth, leading to special materials. Ion implantation in situ of those materials would thus lead uninterruptedly to new substances. Accelerators for space require special design. On the one hand it is possible to forego vacuum systems simplifying the design and operation but, on the other hand, it is necessary to pay special attention to heat dissipation. Hence it is necessary to construct a simulator in vacuum to properly test prototypes under conditions prevailing in space

  9. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Keefe, D.; Sessler, A.M.

    1980-07-01

    Inertial fusion has not yet been as well explored as magnetic fusion but can offer certain advantages as an alternative source of electric energy for the future. Present experiments use high-power beams from lasers and light-ion diodes to compress the deuterium-tritium (D-T) pellets but these will probably be unsuitable for a power plant. A more promising method is to use intense heavy-ion beams from accelerator systems similar to those used for nuclear and high-energy physics; the present paper addresses itself to this alternative. As will be demonstrated the very high beam power needed poses new design questions, from the ion source through the accelerating system, the beam transport system, to the final focus. These problems will require extensive study, both theoretically and experimentally, over the next several years before an optimum design for an inertial fusion driver can be arrived at

  10. Adsorption of palladium ions by modified carbons from rice husks

    International Nuclear Information System (INIS)

    Mostafa, M.R.

    1994-01-01

    Steam activated carbon of high surface area does not show palladium ions adsorption. Treatment of this carbon with HF acid increases to a great extent the gas adsorption capacity expressed as nitrogen surface area as well as the adsorption capacity of palladium ions from aqueous solution. HHB was loaded in different amounts on to these carbons. The acid sites represent the active fraction of the surface on which the adsorption palladium ions proceed. The uptake of palladium ions by HHB treated carbons is related to the total number of HHB molecules loaded on the carbon surface. (author)

  11. ELectron stopping of heavy ions in a matter

    International Nuclear Information System (INIS)

    Akhiezer, I.A.; Davydov, L.N.

    1978-01-01

    The theory of heavy ion stopping by electrons in solids is analyzed with an aim to establish which physical mechanisms are of importance at different ion velocity values v. The theory is presented for deep inelastic collisions taking the main part in stopping at v > Zsub(1)sup(1/3) v 0 (z 1 is the atomic number of the ion, v 0 is the Bohr velocity). Elastic scattering (relative to the incident ion) are investigated. It is shown that the contribution from these processes to the stopping cross-section is predominant at Zsub(1)sup(1/3) v 0 > v > Zsub(1)sup(2/3) v 0

  12. Versatile lipid profiling by liquid chromatography–high resolution mass spectrometry using all ion fragmentation and polarity switching. Preliminary application for serum samples phenotyping related to canine mammary cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gallart-Ayala, H., E-mail: laberca@oniris-nantes.fr [LUNAM, Ecole Nationale Vétérinaire, Agroalimentaire et de l’Alimentation Nantes Atlantique (Oniris), USC 1329 INRA Laboratoire d’Etude des résidus et Contaminants dans les Aliments (LABERCA), Site de la Chantrerie – CS50707, 44307 Nantes cedex 3 (France); Courant, F.; Severe, S.; Antignac, J.-P. [LUNAM, Ecole Nationale Vétérinaire, Agroalimentaire et de l’Alimentation Nantes Atlantique (Oniris), USC 1329 INRA Laboratoire d’Etude des résidus et Contaminants dans les Aliments (LABERCA), Site de la Chantrerie – CS50707, 44307 Nantes cedex 3 (France); Morio, F.; Abadie, J. [LUNAM, Ecole Nationale Vétérinaire, Agroalimentaire et de l’Alimentation Nantes Atlantique (Oniris), Cancers Animaux, Modèles pour la Recherche en Oncologie Comparée (AMaROC), Site de la Chantrerie–CS50707, 44307 Nantes cedex 3 (France); Le Bizec, B. [LUNAM, Ecole Nationale Vétérinaire, Agroalimentaire et de l’Alimentation Nantes Atlantique (Oniris), USC 1329 INRA Laboratoire d’Etude des résidus et Contaminants dans les Aliments (LABERCA), Site de la Chantrerie – CS50707, 44307 Nantes cedex 3 (France)

    2013-09-24

    Graphical abstract: -- Highlights: •Lipidomics, high resolution mass spectrometry, polarity switching, serum, canine mammary cancer. -- Abstract: Lipids represent an extended class of substances characterized by such high variety and complexity that makes their unified analyses by liquid chromatography coupled to either high resolution or tandem mass spectrometry (LC–HRMS or LC–MS/MS) a real challenge. In the present study, a new versatile methodology associating ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC–HRMS/MS) have been developed for a comprehensive analysis of lipids. The use of polarity switching and “all ion fragmentation” (AIF) have been two action levels particularly exploited to finally permit the detection and identification of a multi-class and multi-analyte extended range of lipids in a single run. For identification purposes, both higher energy collision dissociation (HCD) and in-source CID (collision induced dissociation) fragmentation were evaluated in order to obtain information about the precursor and product ions in the same spectra. This approach provides both class-specific and lipid-specific fragments, enhancing lipid identification. Finally, the developed method was applied for differential phenotyping of serum samples collected from pet dogs developing spontaneous malignant mammary tumors and health controls. A biological signature associated with the presence of cancer was then successfully revealed from this lipidome analysis, which required to be further investigated and confirmed at larger scale.

  13. Versatile lipid profiling by liquid chromatography–high resolution mass spectrometry using all ion fragmentation and polarity switching. Preliminary application for serum samples phenotyping related to canine mammary cancer

    International Nuclear Information System (INIS)

    Gallart-Ayala, H.; Courant, F.; Severe, S.; Antignac, J.-P.; Morio, F.; Abadie, J.; Le Bizec, B.

    2013-01-01

    Graphical abstract: -- Highlights: •Lipidomics, high resolution mass spectrometry, polarity switching, serum, canine mammary cancer. -- Abstract: Lipids represent an extended class of substances characterized by such high variety and complexity that makes their unified analyses by liquid chromatography coupled to either high resolution or tandem mass spectrometry (LC–HRMS or LC–MS/MS) a real challenge. In the present study, a new versatile methodology associating ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC–HRMS/MS) have been developed for a comprehensive analysis of lipids. The use of polarity switching and “all ion fragmentation” (AIF) have been two action levels particularly exploited to finally permit the detection and identification of a multi-class and multi-analyte extended range of lipids in a single run. For identification purposes, both higher energy collision dissociation (HCD) and in-source CID (collision induced dissociation) fragmentation were evaluated in order to obtain information about the precursor and product ions in the same spectra. This approach provides both class-specific and lipid-specific fragments, enhancing lipid identification. Finally, the developed method was applied for differential phenotyping of serum samples collected from pet dogs developing spontaneous malignant mammary tumors and health controls. A biological signature associated with the presence of cancer was then successfully revealed from this lipidome analysis, which required to be further investigated and confirmed at larger scale

  14. The relative influence of metal ion binding sites in the I-like domain and the interface with the hybrid domain on rolling and firm adhesion by integrin alpha4beta7.

    Science.gov (United States)

    Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A

    2004-12-31

    We examined the effect of conformational change at the beta(7) I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin alpha(4)beta(7). An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the alpha(4) beta(7) headpiece. Wild-type alpha(4)beta(7) mediates rolling adhesion in Ca(2+) and Ca(2+)/Mg(2+) but firm adhesion in Mg(2+) and Mn(2+). Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn(2+), confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn(2+). Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion.

  15. The Relative Influence of Metal Ion Binding Sites in the I-like Domain and the Interface with the Hybrid Domain on Rolling and Firm Adhesion by Integrin α4β7*

    Science.gov (United States)

    Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A.

    2015-01-01

    We examined the effect of conformational change at the β7 I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin α4β7. An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the α4β7 headpiece. Wild-type α4β7 mediates rolling adhesion in Ca2+ and Ca2+/Mg2+ but firm adhesion in Mg2+ and Mn2+. Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn2+, confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn2+. Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion. PMID:15448154

  16. Versatile lipid profiling by liquid chromatography-high resolution mass spectrometry using all ion fragmentation and polarity switching. Preliminary application for serum samples phenotyping related to canine mammary cancer.

    Science.gov (United States)

    Gallart-Ayala, H; Courant, F; Severe, S; Antignac, J-P; Morio, F; Abadie, J; Le Bizec, B

    2013-09-24

    Lipids represent an extended class of substances characterized by such high variety and complexity that makes their unified analyses by liquid chromatography coupled to either high resolution or tandem mass spectrometry (LC-HRMS or LC-MS/MS) a real challenge. In the present study, a new versatile methodology associating ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-HRMS/MS) have been developed for a comprehensive analysis of lipids. The use of polarity switching and "all ion fragmentation" (AIF) have been two action levels particularly exploited to finally permit the detection and identification of a multi-class and multi-analyte extended range of lipids in a single run. For identification purposes, both higher energy collision dissociation (HCD) and in-source CID (collision induced dissociation) fragmentation were evaluated in order to obtain information about the precursor and product ions in the same spectra. This approach provides both class-specific and lipid-specific fragments, enhancing lipid identification. Finally, the developed method was applied for differential phenotyping of serum samples collected from pet dogs developing spontaneous malignant mammary tumors and health controls. A biological signature associated with the presence of cancer was then successfully revealed from this lipidome analysis, which required to be further investigated and confirmed at larger scale. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Ion cyclotron resonance heating

    International Nuclear Information System (INIS)

    Tajima, T.

    1982-01-01

    Ion cyclotron resonance heating of plasmas in tokamak and EBT configurations has been studied using 1-2/2 and 2-1/2 dimensional fully self-consistent electromagnetic particle codes. We have tested two major antenna configurations; we have also compared heating efficiencies for one and two ion species plasmas. We model a tokamak plasma with a uniform poloidal field and 1/R toroidal field on a particular q surface. Ion cyclotron waves are excited on the low field side by antennas parallel either to the poloidal direction or to the toroidal direction with different phase velocities. In 2D, minority ion heating (vsub(perpendicular)) and electron heating (vsub(parallel),vsub(perpendicular)) are observed. The exponential electron heating seems due to the decay instability. The minority heating is consistent with mode conversion of fast Alfven waves and heating by electrostatic ion cyclotron modes. Minority heating is stronger with a poloidal antenna. The strong electron heating is accompanied by toroidal current generation. In 1D, no thermal instability was observed and only strong minority heating resulted. For an EBT plasma we model it by a multiple mirror. We have tested heating efficiency with various minority concentrations, temperatures, mirror ratios, and phase velocities. In this geometry we have beach or inverse beach heating associated with the mode conversion layer perpendicular to the toroidal field. No appreciable electron heating is observed. Heating of ions is linear in time. For both tokamak and EBT slight majority heating above the collisional rate is observed due to the second harmonic heating. (author)

  18. Stopping power for heavy ions in low energy region

    International Nuclear Information System (INIS)

    Kitagawa, Mitsuo

    1983-01-01

    Review is made for the study on the power for stopping heavy ions. The studies on the power for stopping heavy ions passing through materials have been developed in the last twenty years due to the accuracy improvement in the data analysis of the power for stopping light ions, the requirement of data establishment on the power for stopping heavy ions from fusion research and the development of the experimental studies by heavy-ion accelerators. The relation between the analysis of the power for stopping heavy ions and the power for stopping light ions is described from the standpoint that the results on the power for stopping light ions serve as the guide for the study on the power for stopping heavy ions. Both at present and in future. The analysis of stopping power data with the accuracy from +-10 to 20 % is possible from the theoretical analysis of effective electric charge and its systematic table of the numerical data. The outline of the scaling rule on effective electric charge is discussed. The deviation of the experimental data from the scaling rule is discussed by comparing with the measured values of effective electric charge ratio. Various analyses of the power for stopping heavy ions are summarized. (Asami, T.)

  19. Ion separation from dilute electrolyte solutions by nanofiltration

    International Nuclear Information System (INIS)

    Garcia, Corazon M.

    2000-03-01

    Nanofiltration (NF) is a pressure-driven process which is considered potential for the separation of ionic species selectively from solutions containing mixture of electrolyte solutes. The lower operating pressure requirement of NF than reverse osmosis (RO) makes the earlier potentially economical. In the separation of ions, many authors believed that there are membranes with characteristic fixed surface charge and that the mechanism of separation of ions is by the differences in valences of the ions. In this study, experiments involving dilute single-solute and multiple-solute electrolyte solutions were performed using three different NF membranes. Permeate fluxes and ion rejections of the different species of ions in samples of permeate solutions were measured at varied conditions. The mechanism of separation in NF was determined based on the analysis of the trends and behavior of ion rejection relative to the solution temperature, pressure, type of solute, feed concentration and feed solution pH. The results of the experiments show that there is no evidence of the presence of fixed surface charge on the NF membranes. Ion separation was made possible by the combination of sieve effect and ion-hydration effect. Ions having higher hydration numbers showed higher ion rejection than those having lower hydration numbers. A method to determine the effective membrane pore size of NF membranes using hydrodynamic model was proposed. The proposed method is based on the assumptions that the membrane is neutral and that the separation is based on sieving effect. (Author)

  20. Fast heavy ion collisions with C60: Collective excitation

    International Nuclear Information System (INIS)

    Kadhane, Umesh; Kelkar, A.H.; Misra, D.; Kumar, Ajay; Tribedi, L.C.

    2006-01-01

    Ionization and fragmentation of C 60 in collision with 5 MeV/μm O 6+ ions are studied using recoil ion ToF method. Relative ionization cross sections up to C 60 4+ are determined. The qualitative trend for different C 60 charge states was compared against simple plasmon excitation model

  1. Plasmon band gap generated by intense ion acoustic waves

    International Nuclear Information System (INIS)

    Son, S.; Ku, S.

    2010-01-01

    In the presence of an intense ion acoustic wave, the energy-momentum dispersion relation of plasmons is strongly modified to exhibit a band gap structure. The intensity of an ion acoustic wave might be measured from the band gap width. The plasmon band gap can be used to block the nonlinear cascading channel of the Langmuir wave decay.

  2. Electron spin resonance investigations on polycarbonate irradiated with U ions

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I.; Reyes-Romero, J

    2001-12-01

    Electron spin resonance investigations on polycarbonate irradiated with uranium ions are reported. The dependence of the resonance line parameters (line intensity, line width, double integral) on penetration depth and dose is studied. The nature of free radicals induced in polycarbonate by the incident ions is discussed in relation with the track structure. The presence of severe exchange interactions among free radicals is noticed.

  3. Mass spectrometer and method with improved ion transmission

    International Nuclear Information System (INIS)

    Douglas, D.J.; French, J.B.

    1992-01-01

    This invention relates to a mass analyzer, and to a method of operating a mass analyzer, of the kind in which ions are transmitted through a first rod set for focussing and separation from an accompanying gas, before passing through a mass filter rod set which which permits transmission only of ions of a selected mass to charge ratio. (author). 19 figs

  4. Ion-selective electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Mikhelson, Konstantin N. [St. Petersburg State Univ. (Russian Federation). Ion-Selective Electrode Laboratory

    2013-06-01

    Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis as well as further uses in chemistry and life sciences. Based on his profound experience as a researcher in ISEs and a course instructor, the author summarizes current knowledge for advanced teaching and training purposes with a particular focus on ionophore-based ISEs. Coverage includes the basics of measuring with ISEs, essential membrane potential theory and a comprehensive overview of the various classes of ion-selective electrodes. The principles of constructing ISEs are outlined, and the transfer of methods into routine analysis is considered.

  5. Ion beam texturing

    Science.gov (United States)

    Hudson, W. R.

    1977-01-01

    A microscopic surface texture was created by sputter-etching a surface while simultaneously sputter-depositing a lower sputter yield material onto the surface. A xenon ion-beam source was used to perform the texturing process on samples as large as 3-cm diameter. Textured surfaces have been characterized with SEM photomicrographs for a large number of materials including Cu, Al, Si, Ti, Ni, Fe, stainless steel, Au, and Ag. A number of texturing parameters are studied including the variation of texture with ion-beam powder, surface temperature, and the rate of texture growth with sputter etching time.

  6. Magnetic ions in crystals

    CERN Document Server

    Stevens, K W

    2014-01-01

    There have been many demonstrations, particularly for magnetic impurity ions in crystals, that spin-Hamiltonians are able to account for a wide range of experimental results in terms of much smaller numbers of parameters. Yet they were originally derived from crystal field theory, which contains a logical flaw; electrons on the magnetic ions are distinguished from those on the ligands. Thus there is a challenge: to replace crystal field theory with one of equal or greater predictive power that is based on a surer footing. The theory developed in this book begins with a generic Hamiltonian, on

  7. [Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1990-01-01

    At Brookhaven National Laboratory, participation in the E802 Experiment, which is the first major heavy-ion experiment at the BNL-AGS, was the main focus of the group during the past four years. The emphases of the E802 experiment were on (a) accurate particle identification and measurements of spectra over a wide kinematical domain (5 degree LAB < 55 degree, p < 20 GeV/c); and (b) measurements of small-angle two-particle correlations, with event characterization tools: multiplicity array, forward and large-angle calorimeters. This experiment and other heavy ion collision experiments are discussed in this report

  8. Secondary ion emission

    International Nuclear Information System (INIS)

    Krohn, V.E.

    1976-01-01

    The Saha-Langmuir equation that describes the equilibrium emission process, surface ionization, has also been used to describe ion yields observed in the non-equilibrium emission process, sputtering. In describing sputtering, it is probably best to include the potential due to an image charge in the expression for negative as well as positive ion yield and to treat the work function and the temperature as parameters having limited physical significance. Arguments are presented to suggest that sputtered material is not emitted from a plasma. (Auth.)

  9. Heavy ion collisions

    International Nuclear Information System (INIS)

    Jacak, B.V.

    1994-01-01

    Heavy ion collisions at very high energies provide an opportunity to recreate in the laboratory the conditions which existed very early in the universe, just after the big bang. We prepare matter at very high energy density and search for evidence that the quarks and gluons are deconfined. I describe the kinds of observables that are experimentally accessible to characterize the system and to search for evidence of new physics. A wealth of information is now available from CERN and BNL heavy ion experiments. I discuss recent results on two particle correlations, strangeness production, and dilepton and direct photon distributions

  10. Ion-selective electrodes

    CERN Document Server

    Mikhelson, Konstantin N

    2013-01-01

    Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis as well as further uses in chemistry and life sciences. Based on his profound experience as a researcher in ISEs and a course instructor, the author summarizes current knowledge for advanced teaching and training purposes with a particular focus on ionophore-based ISEs. Coverage includes the basics of measuring with ISEs, essential membrane potential theory and a comprehensive overview of the various classes of ion-selective electrodes. The principles of constructing I

  11. Double chamber ion source

    International Nuclear Information System (INIS)

    Uman, M.F.; Winnard, J.R.; Winters, H.F.

    1978-01-01

    The ion source is comprised of two discharge chambers one of which is provided with a filament and an aperture leading into the other chamber which in turn has an extraction orifice. A low voltage arc discharge is operated in an inert gas atmosphere in the filament chamber while an arc of higher voltage is operated in the second ionization chamber which contains a vapor which will give the desired dopant ion species. The entire source is immersed in an axial magnetic field parallel to a line connecting the filament, the aperture between the two chambers and the extraction orifice. (author)

  12. Asymmetric ion trap

    Science.gov (United States)

    Barlow, Stephan E.; Alexander, Michael L.; Follansbee, James C.

    1997-01-01

    An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

  13. [Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1991-01-01

    The present document describes our second-year application for a continuation grant on relativistic heavy-ion research at Nevis Laboratories, Columbia University, over the two-year period starting from November 15, 1990. The progress during the current budget year is presented. This year, construction of RHIC officially began. As a result, the entire Nevis nuclear physics group has made a coherent effort to create new proposal for an Open Axially Symmetric Ion Spectrometer (OASIS) proposal. Future perspectives and our plans for this proposal are described

  14. Small Column Ion Exchange

    International Nuclear Information System (INIS)

    Huff, Thomas

    2010-01-01

    Small Column Ion Exchange (SCIX) leverages a suite of technologies developed by DOE across the complex to achieve lifecycle savings. Technologies are applicable to multiple sites. Early testing supported multiple sites. Balance of SRS SCIX testing supports SRS deployment. A forma Systems Engineering Evaluation (SEE) was performed and selected Small Column Ion Exchange columns containing Crystalline Silicotitanate (CST) in a 2-column lead/lag configuration. SEE considered use of Spherical Resorcinol-Formaldehyde (sRF). Advantages of approach at SRS include: (1) no new buildings, (2) low volume of Cs waste in solid form compared to aqueous strip effluent; and availability of downstream processing facilities for immediate processing of spent resin.

  15. Novel wave/ion beam interaction approach to isotope separation

    International Nuclear Information System (INIS)

    Post, R.F.; Lowder, R.S.; Schwager, L.A.; Barr, W.L.; Warner, B.E.

    1993-02-01

    Numerical simulations and experimental studies have been made related to the possibility of employing an externally imposed electrostatic potential wave to separate isotopes. This wave/ion interaction is a sensitive function of the wave/ion difference velocity and for the appropriate wave amplitude and wave speed, a lighter faster isotope will be reflected by the wave to a higher energy while leaving heavier, slower isotopes virtually undisturbed in energy -- allowing subsequent ion separation by simple energy discrimination. In these experiments, a set of some 200 individual, electrodes, which surrounded a microamp beam of neon ions, was used to generate the wave. Measurements of the wave amplitudes needed for ion reflection and measurements of the final energies of those reflected ions are consistent with values expected from simple kinetic arguments and with the more detailed results of numeric simulations

  16. Method of pyrolysis for spent ion-exchange resins

    International Nuclear Information System (INIS)

    Aoyama, Yoshiyuki; Matsuda, Masami; Kawamura, Fumio; Yusa, Hideo.

    1985-01-01

    Purpose: To prevent the generation of noxious sulfur oxide and ammonia on the pyrolysis for spent ion-exchange resins discharged from nuclear power plants. Method: In the case where the pyrolysis is made for the cationic exchange resins having sulfonic acids as the ion-exchange group, alkali metals or alkaline earth metals capable of reacting with sulfonic acid groups to form solid sulfates are previously deposited by way of ion-exchange reactions prior to the pyrolysis. In another case of the anionic exchange resins having quarternary ammonium groups as the ion-exchange groups, halogenic elements capable of reacting with the ammonium groups to form solid ammonium salts are deposited to the ion-exchange resins through ion-exchange reactions prior to the pyrolysis. As a result, the amount of the binders used can be reduced, and this method can be used in a relatively simple processing facility. (Horiuchi, T.)

  17. Principal parameters of classical multiply charged ion sources

    International Nuclear Information System (INIS)

    Winter, H.; Wolf, B.H.

    1974-01-01

    A review is given of the operational principles of classical multiply charged ion sources (operating sources for intense beams of multiply charged ions using discharge plasmas; MCIS). The fractional rates of creation of multiply charged ions in MCIS plasmas cannot be deduced from the discharge parameters in a simple manner; they depend essentially on three principal parameters, the density and energy distribution of the ionizing electrons, and the confinement time of ions in the ionization space. Simple discharge models were used to find relations between principal parameters, and results of model calculations are compared to actually measured charge state density distributions of extracted ions. Details of processes which determine the energy distribution of ionizing electrons (heating effects), confinement times of ions (instabilities), and some technical aspects of classical MCIS (cathodes, surface processes, conditioning, life time) are discussed

  18. Cluster ions and van der Waals molecules

    CERN Document Server

    Smirnov, Boris M

    1992-01-01

    This review discusses current ideas in the physics and chemistry of cluster ions and Van der Waals molecules as well as presenting numerical data on their parameters and the processes involving them. It is also a detailed reference on basic data relating to many species.

  19. Trimethylphosphide isomerization in lanthanum ions presence

    International Nuclear Information System (INIS)

    Zacharias, M.A.; Massabni, A.M.G.

    1984-01-01

    The integration between the trimethilphosphide and the lanthanum ions carry to the formation of solid complexes in a relation of 6:1 where the ligand is the phosphonate what is resultant of the isomerization of trimetylphosphite. By the RMN -1 H and infra-red spectra the products were characterized. (L.M.J.) [pt

  20. Charging of dust grains in a plasma with negative ions

    International Nuclear Information System (INIS)

    Kim, Su-Hyun; Merlino, Robert L.

    2006-01-01

    The effect of negative ions on the charging of dust particles in a plasma is investigated experimentally. A plasma containing a very low percentage of electrons is formed in a single-ended Q machine when SF 6 is admitted into the vacuum system. The relatively cold Q machine electrons (T e ≅0.2 eV) readily attach to SF 6 molecules to form SF 6 - negative ions. Calculations of the dust charge indicate that for electrons, negative ions, and positive ions of comparable temperatures, the charge (or surface potential) of the dust can be positive if the positive ion mass is smaller than the negative ion mass and if ε, the ratio of the electron to positive ion density, is sufficiently small. The Q machine plasma is operated with K + positive ions (mass 39 amu) and SF 6 - negative ions (mass 146 amu), and also utilizes a rotating cylinder to dispense dust into the plasma column. Analysis of the current-voltage characteristics of a Langmuir probe in the dusty plasma shows evidence for the reduction in the (magnitude) of the negative dust charge and the transition to positively charged dust as the relative concentration of the residual electrons is reduced. Some remarks are offered concerning experiments that could become possible in a dusty plasma with positive grains