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Sample records for solar-pumped iodine laser

  1. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, K. S.

    1985-01-01

    This semiannual progress report covers the period from April 1, 1985 to Sept. 30, 1985 under NASA grant NAS1-441 entitled direct solar pumped iodine laser amplifier. During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator was carried out before the amplifier studies. The amplifier studies are postponed to the extended period following completion of the parametric studies. In addition, the kinetic modeling of a solar pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) the radiation characteristics of solar simulator and the parametric characteristics of photodissociation iodine laser continuously pumped by a Vortek solar simulator; (2) kinetic modeling of a solar pumped iodine laser amplifier; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

  2. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, K. S.

    1986-01-01

    During this period the parametric studies of the iodine laser oscillator pumped by a Vortek simulator were carried out before amplifier studies. The amplifier studies are postponed to the extended period after completing the parametric studies. In addition, the kinetic modeling of a solar-pumped iodine laser amplifier, and the experimental work for a solar pumped dye laser amplifier are in progress. This report contains three parts: (1) a 10 W CW iodine laser pumped by a Vortek solar simulator; (2) kinetic modeling to predict the time to lasing threshold, lasing time, and energy output of solar-pumped iodine laser; and (3) the study of the dye laser amplifier pumped by a Tamarack solar simulator.

  3. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1987-01-01

    The improvement on the collection system of the Tarmarack Solar Simulator beam was attemped. The basic study of evaluating the solid state laser materials for the solar pumping and also the work to construct a kinetic model algorithm for the flashlamp pumped iodine lasers were carried out. It was observed that the collector cone worked better than the lens assembly in order to collect the solar simulator beam and to focus it down to a strong power density. The study on the various laser materials and their lasing characteristics shows that the neodymium and chromium co-doped gadolinium scandium gallium garnet (Nr:Cr:GSGG) may be a strong candidate for the high power solar pumped solid state laser crystal. On the other hand the improved kinetic modeling for the flashlamp pumped iodine laser provides a good agreement between the theoretical model and the experimental data on the laser power output, and predicts the output parameters of a solar pumped iodine laser.

  4. Direct solar-pumped iodine laser amplifier

    NASA Astrophysics Data System (ADS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1987-02-01

    The improvement on the collection system of the Tarmarack Solar Simulator beam was attemped. The basic study of evaluating the solid state laser materials for the solar pumping and also the work to construct a kinetic model algorithm for the flashlamp pumped iodine lasers were carried out. It was observed that the collector cone worked better than the lens assembly in order to collect the solar simulator beam and to focus it down to a strong power density. The study on the various laser materials and their lasing characteristics shows that the neodymium and chromium co-doped gadolinium scandium gallium garnet (Nr:Cr:GSGG) may be a strong candidate for the high power solar pumped solid state laser crystal. On the other hand the improved kinetic modeling for the flashlamp pumped iodine laser provides a good agreement between the theoretical model and the experimental data on the laser power output, and predicts the output parameters of a solar pumped iodine laser.

  5. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon

    1990-01-01

    The optimum conditions of a solar pumped iodine laser are found in this research for the case of a continuous wave operation and a pulsed operation. The optimum product of the pressure(p) inside the laser tube and the tube diameter(d) was pd=40 approx. 50 torr-cm on the contrary to the case of a high intensity flashlamp pumped iodine laser where the optimum value of the product is known to be pd=150 torr-cm. The pressure-diameter product is less than 1/3 of that of the high power iodine laser. During the research period, various laser materials were also studied for solar pumping. Among the laser materials, Nd:YAG is found to have the lowest laser threshold pumping intensity of about 200 solar constant. The Rhodamine 6G was also tested as the solar pumped laser material. The threshold pumping power was measured to be about 20,000 solar constant. The amplification experiment for a continuously pumped iodine laser amplifier was performed using Vortek solar simulator and the amplification factors were measured for single pass amplification and triple pass amplification of the 15 cm long amplifier tube. The amplification of 5 was obtained for the triple pass amplification.

  6. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

    1989-01-01

    This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

  7. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.

    1987-01-01

    This semiannual progress report covers the period from March 1, 1987 to September 30, 1987 under NASA grant NAG1-441 entitled 'Direct solar-pumped iodine laser amplifier'. During this period Nd:YAG and Nd:Cr:GSGG crystals have been tested for the solar-simulator pumped cw laser, and loss mechanisms of the laser output power in a flashlamp-pumped iodine laser also have been identified theoretically. It was observed that the threshold pump-beam intensities for both Nd:YAG and Nd:Cr:GSGG crystals were about 1000 solar constants, and the cw laser operation of the Nd:Cr:GSGG crystal was more difficult than that of the Nd:YAG crystal under the solar-simulator pumping. The possibility of the Nd:Cr:GSGG laser operation with a fast continuously chopped pumping was also observed. In addition, good agreement between the theoretical calculations and the experimental data on the loss mechanisms of a flashlamp-pumped iodine laser at various fill pressures and various lasants was achieved.

  8. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In Heon; Kim, Khong Hon; Stock, Larry V.

    1988-01-01

    A XeCl laser pumped iodine laser oscillator was developed which will be incorporated into the Master Oscillator Power Amplifier (MOPA) system. The developed XeCl laser produces output energy of about 60 mJ per pulse. The pulse duration was about 10 nsec. The kinetic model for the solar-pumped laser was refined and the algorithm for the calculation of a set of rate equations was improved to increase the accuracy and the efficiency of the calculation. The improved algorithm was applied to explain the existing experimental data taken from a flashlamp pumped iodine laser for three kinds of lasants, i-C3F7I, n-C4F9I, and t-C4F9I. Various solid laser materials were evaluated for solar-pumping. The materials studied were Nd:YAG, Nd:YLF, and Cr:Nd:GSGG crystals. The slope efficiency of 0.17 percent was measured for the Nd:YLF near the threshold pump intensity which was 211 solar constants (29W/sq cm). The threshold pump intensity of the Nd:YAG was measured to be 236 solar constants (32W/sq cm) and the near-threshold slope efficiency was 0.12 percent. True CW laser operation of Cr:Nd:GSGG was possible only at pump intensities less than or equal to 1,500 solar constants (203 W/sq cm). This fact was attributed to the high thermal focusing effect of the Cr:Nd:GSGG rod.

  9. Optically (solar) pumped oxygen-iodine lasers

    NASA Astrophysics Data System (ADS)

    Danilov, O. B.; Zhevlakov, A. P.; Yur'ev, M. S.

    2014-07-01

    We present the results of theoretical and experimental studies demonstrating the possibility of developing an oxygen-iodine laser (OIL) with direct optical pumping of molecular oxygen involving inter-molecular interaction with charge transfer from donor molecule (buffer gas) to acceptor molecule (oxygen). This interaction lifts degeneracy of the lower energy states of molecular oxygen and increases its absorption cross section in the visible spectral region and the UV Herzberg band, where high quantum yield of singlet oxygen is achieved (QY ˜ 1 and QY ˜ 2, respectively) at the same time. A pulse-periodic optical pump sources with pulse energy of ˜50 kJ, pulse duration of ˜25 μs, and repetition rate of ˜10 Hz, which are synchronized with the mechanism of singlet oxygen generation, are developed. This allows implementation of a pulse-periodic oxygen-iodine laser with an efficiency of ˜25%, optical efficiency of ˜40%, and parameter L/ T ˜ 1/1.5, where T is the thermal energy released in the laser active medium upon generation of energy L. It is demonstrated that, under direct solar pumping of molecular oxygen, the efficiency parameter of the OIL can reach L/ T ˜ 1/0.8 in a wide range of scaling factors.

  10. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Kim, K. H.; Stock, L. V.

    1986-01-01

    In order to evaluate the feasibility of the solar pumped dye laser, the parametric study of a dye laser amplifier pumped by a solar simulator and flashlamp was carried out, and the amplifier gains were measured at various pump beam irradiances on the dye cell. Rhodamine 6G was considered as a candidate for the solar pumped laser because of its good utilization of the solar spectrum and high quantum efficiency. The measurement shows that a solar concentration of 20,000 is required to reach the threshold of the dye. The work to construct a kinetic model algorithm which predicts the output parameter of laser was progressed. The kinetic model was improved such that there is good agreement between the theoretical model and experimental data for the systems defined previously as flashlamp pumped laser oscillator, and the long path length solar pumped laser.

  11. Direct solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Han, Kwang S.; Hwang, In H.; Stock, Larry V.

    1988-01-01

    A XeCl laser which was developed earlier for an iodine laser oscillator was modified in order to increase the output pulse energy of XeCl laser so that the iodine laser output energy could be increased. The electrical circuit of the XeCl laser was changed from a simple capacitor discharge circuit of the XeCl laser to a Marx system. Because of this improvement the output energy from the XeCl laser was increased from 60 mj to 80 mj. Subsequently, iodine laser output energy was increased from 100 mj to 3 mj. On the other hand, the energy storage capability and amplification characteristics of the Vortek solar simulator-pumped amplifier was calculated expecting the calculated amplification factor is about 2 and the energy extraction efficiency is 26 percent due to the very low input energy density to the amplifier. As a result of an improved kinetic modeling for the iodine solar simulator pumped power amplifier, it is found that the I-2 along the axis of the tube affects seriously the gain profile. For the gas i-C3F7I at the higher pressures, the gain will decrease due to the I-2 as the pumping intensity increases, and at these higher pressures an increase in flow velocity will increase the gain.

  12. Amplified spontaneous emission in solar-pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Cho, Yong S.; Hwang, In H.; Han, Kwang S.; Lee, Ja H.

    1992-01-01

    The amplified spontaneous emission (ASE) from a long pulse, solar-simulating radiation pumped iodine laser amplifier is studied. The ASE threshold pump intensity is almost proportional to the inverse of the laser gain length when the gas pressure is constant in the laser tube.

  13. Direct solar-pumped iodine laser amplifier. Final report, 1 March 1984-28 February 1990

    SciTech Connect

    Han, K.S.; Hwang, I.H.

    1990-03-01

    The optimum conditions of a solar pumped iodine laser are found in this research for the case of a continuous wave operation and a pulsed operation. The optimum product of the pressure(p) inside the laser tube and the tube diameter(d) was pd=40 approx. 50 torr-cm on the contrary to the case of a high intensity flashlamp pumped iodine laser where the optimum value of the product is known to be pd=150 torr-cm. The pressure-diameter product is less than 1/3 of that of the high power iodine laser. During the research period, various laser materials were also studied for solar pumping. Among the laser materials, Nd:YAG is found to have the lowest laser threshold pumping intensity of about 200 solar constant. The Rhodamine 6G was also tested as the solar pumped laser material. The threshold pumping power was measured to be about 20,000 solar constant. The amplification experiment for a continuously pumped iodine laser amplifier was performed using Vortek solar simulator and the amplification factors were measured for single pass amplification and triple pass amplification of the 15 cm long amplifier tube. The amplification of 5 was obtained for the triple pass amplification.

  14. Design and chemical synthesis of iodine-containing molecules for application to solar-pumped I* lasers

    NASA Technical Reports Server (NTRS)

    Shiner, Christopher S.

    1986-01-01

    Research is directed toward the design and synthesis of new media for solar-pumped I* lasers. Since the most effective existing lasants are perfluoroalkyl iodides, a strategy was proposed for the development of improved materials of this type with absorption maxima at 300 nm. Absorption spectra were synthesized and measured for prototypical species containing iodine bound to boron, iron, and cobalt.

  15. Directly solar-pumped iodine laser for beamed power transmission in space

    NASA Technical Reports Server (NTRS)

    Choi, S. H.; Meador, W. E.; Lee, J. H.

    1992-01-01

    A new approach for development of a 50-kW directly solar-pumped iodine laser (DSPIL) system as a space-based power station was made using a confocal unstable resonator (CUR). The CUR-based DSPIL has advantages, such as performance enhancement, reduction of total mass, and simplicity which alleviates the complexities inherent in the previous system, master oscillator/power amplifier (MOPA) configurations. In this design, a single CUR-based DSPIL with 50-kW output power was defined and compared to the MOPA-based DSPIL. Integration of multiple modules for power requirements more than 50-kW is physically and structurally a sound approach as compared to building a single large system. An integrated system of multiple modules can respond to various mission power requirements by combining and aiming the coherent beams at the user's receiver.

  16. A 50-kW Module Power Station of Directly Solar-Pumped Iodine Laser

    NASA Technical Reports Server (NTRS)

    Choi, S. H.; Lee, J. H.; Meador, W. E.; Conway, E. J.

    1997-01-01

    The conceptual design of a 50 kW Directly Solar-Pumped Iodine Laser (DSPIL) module was developed for a space-based power station which transmits its coherent-beam power to users such as the moon, Martian rovers, or other satellites with large (greater than 25 kW) electric power requirements. Integration of multiple modules would provide an amount of power that exceeds the power of a single module by combining and directing the coherent beams to the user's receiver. The model developed for the DSPIL system conservatively predicts the laser output power (50 kW) that appears much less than the laser output (93 kW) obtained from the gain volume ratio extrapolation of experimental data. The difference in laser outputs may be attributed to reflector configurations adopted in both design and experiment. Even though the photon absorption by multiple reflections in experimental cavity setup was more efficient, the maximum secondary absorption amounts to be only 24.7 percent of the primary. However, the gain volume ratio shows 86 percent more power output than theoretical estimation that is roughly 60 percent more than the contribution by the secondary absorption. Such a difference indicates that the theoretical model adopted in the study underestimates the overall performance of the DSPIL. This fact may tolerate more flexible and radical selection of design parameters than used in this design study. The design achieves an overall specific power of approximately 5 W/kg and total mass of 10 metric tons.

  17. Perfluorobutyl iodides as gain media for a solar-pumped iodine laser amplifier

    NASA Technical Reports Server (NTRS)

    Tabibi, Bagher M.; Lee, Min H.; Lee, Ja H.; Weaver, Willard R.

    1987-01-01

    The effectiveness of t-C4F9I and n-C4F9I as gain media for a space-based solar-pumped iodine photodissociation laser is investigated experimentally. The optically coupled flashlamp/amplifier-tube apparatus described by Hwang et al. (1986) is employed, driving the amplifier with 4-microsec 4.2-mJ TEM(00) pulses from a flashlamp-pumped laser oscillator; the variation of amplification with energy-extraction time was monitored by inserting a delay of up to 1 msec between the firing of the two flashlamps and measuring the delay between the optical pulses. The results are presented graphically and briefly characterized. The performance of t-C4F9I is found to be better than that of n-C4F9I (or n-C3F7I), with an absorption band shifted toward the visible (for improved utilization of solar radiation), higher gain (by a factor of 2) at all delay times, and better chemical reversibility. The gain did not depend significantly on temperature in any of the iodides.

  18. Solar pumped laser

    NASA Technical Reports Server (NTRS)

    Lee, J. H.; Hohl, F.; Weaver, W. R. (Inventor)

    1984-01-01

    A solar pumped laser is described in which the lasant is a gas that will photodissociate and lase when subjected to sunrays. Sunrays are collected and directed onto the gas lasant to cause it to lase. Applications to laser propulsion and laser power transmission are discussed.

  19. Laser Doppler velocimetry for continuous flow solar-pumped iodine laser system

    NASA Technical Reports Server (NTRS)

    Tabibi, Bagher M.; Lee, Ja H.

    1991-01-01

    A laser Doppler velocimetry (LDV) system was employed to measure the flow velocity profile of iodide vapor inside laser tubes of 36 mm ID and 20 mm ID. The LDV, which was operated in the forward scatter mode used a low power (15 mW) He-Ne laser beam. Velocity ranges from 1 m/s was measured to within one percent accuracy. The flow velocity profile across the laser tube was measured and the intensity of turbulence was determined. The flow of iodide inside the laser tube demonstrated a mixture of both turbulence and laminar flow. The flowmeter used for the laser system previously was calibrated with the LDV and found to be in good agreement.

  20. Design and chemical synthesis of iodine-containing molecules for application to solar-pumped I* lasers

    NASA Technical Reports Server (NTRS)

    Shiner, C. S.

    1986-01-01

    The design and chemical synthesis of new media for solar pumped iodine molecule lasers are explored. In an effort to prepare an iodo fluorocarbon compound absorbing strongly at 300 nm or above, the synthesis of perfluoro allylic iodides was investigated. These compounds furnish especially stable allylic radicals upon photodissociation. The desired red shift is anticipated in the absorption maximum could correlate with increasing radical stability. This expectation was based upon the analysis, previously reported, of the structures and absorption maxima of compounds studied earlier. A previously unknown substance was prepared, a prototypical target molecule, perfluoro-3-iodocyclopent-1-ene. It was obtained by reaction of perfluorocyclopentene with sulfur trioxide under the influence of antimony pentafluoride catalyst, followed by treatment of the resulting allylic fluorosulfonate with sodium iodide in sulfoland solvent. Preliminary data indicate that the absorption maximum for the iodo fluorocarbon is not shifted significantly to longer wavelength. It is not certain whether this result reflects an unexpected influence of the cyclic structure upon the position of the absorption maximum.

  1. Solar-pumped laser for free space power transmission

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.

    1989-01-01

    Laser power transmission; laser systems; space-borne and available lasers; 2-D and 1 MW laser diode array systems; technical issues; iodine solar pumped laser system; and laser power transmission applications are presented. This presentation is represented by viewgraphs only.

  2. Advanced solar energy conversion. [solar pumped gas lasers

    NASA Technical Reports Server (NTRS)

    Lee, J. H.

    1981-01-01

    An atomic iodine laser, a candidate for the direct solar pumped lasers, was successfully excited with a 4 kW beam from a xenon arc solar simulator, thus proving the feasibility of the concept. The experimental set up and the laser output as functions of operating conditions are presented. The preliminary results of the iodine laser amplifier pumped with the HCP array to which a Q switch for giant pulse production was coupled are included. Two invention disclosures - a laser driven magnetohydrodynamic generator for conversion of laser energy to electricity and solar pumped gas lasers - are also included.

  3. SOLAR PUMPED LASER MICROTHRUSTER

    SciTech Connect

    Rubenchik, A M; Beach, R; Dawson, J; Siders, C W

    2010-02-05

    The development of microsatellites requires the development of engines to modify their orbit. It is natural to use solar energy to drive such engines. For an unlimited energy source the optimal thruster must use a minimal amount of expendable material to minimize launch costs. This requires the ejected material to have the maximal velocity and, hence, the ejected atoms must be as light as possible and be ejected by as high an energy density source as possible. Such a propulsion can be induced by pulses from an ultra-short laser. The ultra-short laser provides the high-energy concentration and high-ejected velocity. We suggest a microthruster system comprised of an inflatable solar concentrator, a solar panel, and a diode-pumped fiber laser. We will describe the system design and give weight estimates.

  4. Design and chemical synthesis of iodine-containing molecules for application to solar-pumped I* lasers

    NASA Technical Reports Server (NTRS)

    Shiner, C. S.

    1985-01-01

    This work is directed toward the design and chemical synthesis of new media for solar-pumped I* lasers. In view of the desirability of preparing a perfluoroalkyl iodide absorbing strongly at 300 nm, the relationship betwen perfluoroalkyl iodide structure and the corresponding absorption wavelength was reexamined. Analysis of existing data suggests that, in this family of compounds, the absorption maximum shifts to longer wavelength, as desired, as the C-I bond in the lasant is progressively weakened. Weakening of the C-I bond correlates, in turn, with increasing stability of the perfluoroalkyl radical formed upon photodissociation of the iodide. The extremely promising absorption characteristics of perfluoro-tert-butyl iodide can be accounted for on this basis. A new technique of diode laser probing to obtain precise yields of I* atoms in photodissociation was also developed.

  5. Solar-pumped solid-state lasers

    SciTech Connect

    Weksler, M.; Shwartz, J.

    1988-06-01

    Results are presented for direct solar pumping of a ND:YAG rod laser. Stable CW output of more than 60 W was obtained with a slope efficiency exceeding 2 percent. A compound parabolic concentrator, designed to increase the solar radiation coupled into the laser rod, was used in these experiments. The results are consistent with predictions based on a simple solar-pumped laser model, which is also presented. Using this model, it is shown that existing laser materials with broad-band absorption characteristics (e.g., alexandrite and Nd:Cr:GSGG) have a potential for better than 10 percent overall conversion efficiency when solar pumped.

  6. Feasibility of solar-pumped dye lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1987-01-01

    Dye laser gains were measured at various pump-beam irradiances on a dye cell in order to evaluate the feasibility of solar pumping. Rhodamine 6G dye was considered as a candidate for the solar-pumped laser because of its high utilization of the solar spectrum and high quantum efficiency. Measurements show that a solar concentration of 20,000 is required to reach the threshold of the dye.

  7. Solar pumped lasers and their applications

    NASA Astrophysics Data System (ADS)

    Lee, Ja H.

    Since 1980, NASA has been pursuing high power solar lasers as part of the space power beaming program. Materials in liquid, solid, and gas phases have been evaluated against the requirements for solar pumping. Two basic characteristics of solar insolation, namely its diffuse irradiance and 5800 K blackbody-like spectrum, impose rather stringent requirements for laser excitation. However, meeting these requirements is not insurmountable as solar thermal energy technology has progressed today, and taking advantage of solar pumping lasers is becoming increasingly attractive. The high density photons of concentrated solar energy have been used for mainly electric power generation and thermal processing of materials by the DOE Solar Thermal Technologies Program. However, the photons can interact with materials through many other direct kinetic paths, and applications of the concentrated photons could be extended to processes requiring photolysis, photosynthesis, and photoexcitation. The use of solar pumped lasers on Earth seems constrained by economics and sociopolitics. Therefore, prospective applications may be limited to those that require use of quantum effects and coherency of the laser in order to generate extremely high value products and services when conventional and inexpensive means are ineffective or impossible. The new applications already proposed for concentrated solar photons, such as destruction of hazardous waste, production of renewable fuel, production of fertilizer, and air/water pollution controls, may benefit from the use of inexpensive solar pumped laser matched with the photochemical kinetics of these processes.

  8. Research on solar pumped liquid lasers

    NASA Technical Reports Server (NTRS)

    Schneider, R. T.; Kurzweg, U. H.; Cox, J. D.; Weinstein, N. H.

    1983-01-01

    A solar pumped liquid laser that can be scaled up to high power (10Mw CW) for space applications was developed. Liquid lasers have the inherent advantage over gases in that they provide much higher lasant densities and thus high power densities. Liquids also have inherent advantages over solids in that they have much higher damage thresholds and are much cheaper to produce for large scale applications. Among the liquid laser media that are potential candidates for solar pumping, the POC13:Nd(3+):ZrC14 liquid was chosen for its high intrinsic efficiency as well as its relatively good stability against decomposition due to protic contamination. The development and testing of the laser liquid and the development of a large solar concentrator to pump the laser was emphasized. The procedure to manufacture the laser liquid must include diagnostic tests of the solvent purity (from protic contamination) at various stages in the production process.

  9. Research on solar pumped liquid lasers

    NASA Technical Reports Server (NTRS)

    Cox, J. D.; Kurzweg, U. H.; Weinstein, N. H.; Schneider, R. T.

    1985-01-01

    A solar pumped liquid laser that can be scaled up to high power (10 mW CW) for space applications was developed. Liquid lasers have the advantage over gases in that they provide much higher lasant densities and thus high-power densities. Liquids also have advantages over solids in that they have much higher damage thresholds and are much cheaper to produce for large scale applications. Among the liquid laser media that are potential candidates for solar pumping, the POC13: Nd sup 3+:ZrC14 liquid was chosen for its high intrinsic efficiency and its relatively good stability against decomposition due to protic contamination. The development of a manufacturing procedure and performance testing of the laser, liquid and the development of an inexpensive large solar concentrator to pump the laser are examined.

  10. Theoretcial studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.; Fong, Z. S.

    1984-01-01

    A method of pumping a COhZ laser by a hot cavity was demonstrated. The cavity, heated by solar radiation, should increase the efficiency of solar pumped lasers used for energy conversion. Kinetic modeling is used to examine the behavior of such a COhZ laser. The kinetic equations are solved numerically vs. time and, in addition, steady state solutions are obtained analytically. The effect of gas heating filling the lower laser level is included. The output power and laser efficiency are obtained as functions of black body temperature and gas ratios (COhZ-He-Ar) and pressures. The values are compared with experimental results.

  11. Solar-pumped gas laser development

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.

    1980-01-01

    A survey of gas properties through detailed kinetic models led to the identification of critical gas parameters for use in choosing appropriate gas combinations for solar pumped lasers. Broadband photoabsorption in the visible or near UV range is required to excite large volumes of gas and to insure good solar absorption efficiency. The photoexcitation density is independent of the absorption bandwidth. The state excited must be a metastable state which is not quenched by the parent gas. The emission bandwidth must be less than 10 A to insure lasing threshold over reasonable gain lengths. The system should show a high degree of chemical reversibility and an insensitivity to increasing temperature. Other properties such as good quantum efficiency and kinetic efficiency are also implied. Although photoexcitation of electronic vibrational transitions is considered as a possible system if the emission bands sufficiently narrow, it appears that photodissociation into atomic metastables is more likely to result in a successful solar pumped laser system.

  12. Solar-pumped CO laser

    NASA Astrophysics Data System (ADS)

    Treanor, Charles E.

    This paper describes a method of converting thermal radiation directly into laser radiation at a wavelength of about 5 micrometers. The working fluid for the laser operation is a mixture of carbon monoxide and argon. The source of thermal radiation is assumed to be a solar oven or electrical oven operating in the range of 2000 to 2500 K. The use of carbon monoxide as the lasing material presents the advantage that the absorbing lines can be pressure broadened to permit efficient absorption of the thermal radiation without unacceptable increases in vibrational relaxation. Estimates of the efficiency, size, and power loading of such a laser are discussed.

  13. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1982-01-01

    Solar-pumped lasers were investigated by comparing experimental results from pulse experiments with steady state calculations. The time varying behavior of an IBr laser is studied. The analysis is only approximate, but indicates that conditions occurring in a pulsed experiment are quite different from those at steady state. The possibility of steady-state lasing in an IBr laser is determined. The effects of high temperatures on the quenching and recombination rates are examined. Although uncertainties in the values of the rate coefficients make it difficult to draw firm conclusions, it seems steady state running may be possible at high temperatures.

  14. Scaling studies of solar pumped lasers

    NASA Technical Reports Server (NTRS)

    Christiansen, W. H.; Chang, J.

    1985-01-01

    A progress report of scaling studies of solar pumped lasers is presented. Conversion of blackbody radiation into laser light has been demonstrated in this study. Parametric studies of the variation of laser mixture composition and laser gas temperature were carried out for CO2 and N2O gases. Theoretical analysis and modeling of the system have been performed. Reasonable agreement between predictions in the parameter variation and the experimental results have been obtained. Almost 200 mW of laser output at 10.6 micron was achieved by placing a small sapphire laser tube inside an oven at 1500 K the tube was filled with CO2 laser gas mixture and cooled by longitudinal nitrogen gas flow.

  15. Scaling studies of solar pumped lasers

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Chang, J.

    1985-08-01

    A progress report of scaling studies of solar pumped lasers is presented. Conversion of blackbody radiation into laser light has been demonstrated in this study. Parametric studies of the variation of laser mixture composition and laser gas temperature were carried out for CO2 and N2O gases. Theoretical analysis and modeling of the system have been performed. Reasonable agreement between predictions in the parameter variation and the experimental results have been obtained. Almost 200 mW of laser output at 10.6 micron was achieved by placing a small sapphire laser tube inside an oven at 1500 K the tube was filled with CO2 laser gas mixture and cooled by longitudinal nitrogen gas flow.

  16. Preliminary conceptual design and weight of a one-megawatt space-based laser power station utilizing a solar-pumped iodine lasant

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

    1987-01-01

    A preliminary conceptual design of a space-based solar-pumped iodide laser emitting 1 MW of laser power for space-to-space power transmission is described. A near-parabolic solar collector focuses sunlight onto the t-C4F9I lasant within a transverse-flow optical cavity. Using waste heat, a thermal system supplies compressor and auxiliary power. The major system components are designed with weight estimates assigned. In particular, it is found that laser efficiency is not a dominant weight factor, the dominant factor being the laser transmission optics. The station mass is 92,000 kg, requiring approximately eight Shuttle flights to LEO, where an orbital transfer vehicle can transport it to the final altitude of 6378 km.

  17. Photovoltaic converters for solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Walker, Gilbert H.; Heinbockel, John H.

    1988-01-01

    The authors describe a mathematical parametric study of converters used to convert laser radiation to electricity for space-based laser power systems. Two different lasers, the 1.06-micron Nd laser and the 1.315-micron iodine laser, are used in the vertical junction converter. The calculated efficiency is 50 percent for a 100-junction Si photovoltaic converter when used with a Nd laser. The calculated efficiency for a 1000-junction Ga(0.53)In(0.47)As photovoltaic converter is 43 percent when used with an iodine laser.

  18. Solar-pumped laser on the Space Station

    SciTech Connect

    Arashi, H.; Oka, Y.; Ishigame, M.

    1985-01-01

    A solid state solar pumped laser system to be used on the Space Station is described. The system is based on an experimental version of a solar pumped Nd:YAG laser which has achieved a maximum power in excess of 18 W in multi-mode. The laser is powered by a paraboloid solar radiation concentrator. A solar pumped gas laser system is recommended for applications requiring a higher output power. Applications of a laser on board the Space Station include optical communication; laser propulsion; energy conversion; and high speed laser processing. Detailed schematic drawings of the solid state and gas laser designs are provided.

  19. Solar pumped continuous wave carbon dioxide laser

    NASA Technical Reports Server (NTRS)

    Yesil, O.; Christiansen, W. H.

    1978-01-01

    In an effort to demonstrate the feasibility of a solar pumped laser concept, gain has been measured in a CO2-He laser medium optically pumped by blackbody radiation. Various gas mixtures of CO2 and He have been pumped by blackbody radiation emitted from an electrically heated oven. Using a CO2 laser as a probe, an optical gain coefficient of 1.8 x 10 to the -3rd/cm has been measured at 10.6 microns for a 9:1 CO2-He mixture at an oven temperature of about 1500 K, a gas temperature of about 400 K and a pressure of about 1 torr. This corresponds to a small signal gain coefficient when allowance is made for saturation effects due to the probe beam, in reasonable agreement with a theoretical value.

  20. Theoretical studies of solar pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, Wynford L.

    1990-01-01

    One concept for collecting solar energy is to use large solar collectors and then use lasers as energy converters whose output beams act as transmission lines to deliver the energy to a destination. The efficiency of the process would be improved if the conversion could be done directly using solar pumped lasers, and the possibility of making such lasers is studied. There are many applications for such lasers, and these are examined. By including the applications first, the requirements for the lasers will be more evident. They are especially applicable to the Space program, and include cases where no other methods of delivering power seem possible. Using the lasers for conveying information and surveillance is also discussed. Many difficulties confront the designer of an efficient system for power conversion. These involve the nature of the solar spectrum, the method of absorbing the energy, the transfer of power into laser beams, and finally, the far field patterns of the beams. The requirements of the lasers are discussed. Specific laser configurations are discussed. The thrust is into gas laser systems, because for space applications, the laser could be large, and also the medium would be uniform and not subject to thermal stresses. Dye and solid lasers are treated briefly. For gas lasers, a chart of the various possibilities is shown, and the various families of gas lasers divided according to the mechanisms of absorbing solar radiation and of lasing. Several specific models are analyzed and evaluated. Overall conclusions for the program are summarized, and the performances of the lasers related to the requirements of various applications.

  1. Key techniques for space-based solar pumped semiconductor lasers

    NASA Astrophysics Data System (ADS)

    He, Yang; Xiong, Sheng-jun; Liu, Xiao-long; Han, Wei-hua

    2014-12-01

    In space, the absence of atmospheric turbulence, absorption, dispersion and aerosol factors on laser transmission. Therefore, space-based laser has important values in satellite communication, satellite attitude controlling, space debris clearing, and long distance energy transmission, etc. On the other hand, solar energy is a kind of clean and renewable resources, the average intensity of solar irradiation on the earth is 1353W/m2, and it is even higher in space. Therefore, the space-based solar pumped lasers has attracted much research in recent years, most research focuses on solar pumped solid state lasers and solar pumped fiber lasers. The two lasing principle is based on stimulated emission of the rare earth ions such as Nd, Yb, Cr. The rare earth ions absorb light only in narrow bands. This leads to inefficient absorption of the broad-band solar spectrum, and increases the system heating load, which make the system solar to laser power conversion efficiency very low. As a solar pumped semiconductor lasers could absorb all photons with energy greater than the bandgap. Thus, solar pumped semiconductor lasers could have considerably higher efficiencies than other solar pumped lasers. Besides, solar pumped semiconductor lasers has smaller volume chip, simpler structure and better heat dissipation, it can be mounted on a small satellite platform, can compose satellite array, which can greatly improve the output power of the system, and have flexible character. This paper summarizes the research progress of space-based solar pumped semiconductor lasers, analyses of the key technologies based on several application areas, including the processing of semiconductor chip, the design of small and efficient solar condenser, and the cooling system of lasers, etc. We conclude that the solar pumped vertical cavity surface-emitting semiconductor lasers will have a wide application prospects in the space.

  2. Perfluorobutyl iodides as gain media for a solar-pumped laser amplifier

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Weaver, Willard R.; Tabibi, Bagher M.

    1988-01-01

    Perfluorobutyl iodides were studied as media for an iodine photodissociation laser amplifier, and photoabsorption cross sections were measured. The results indicate superior performance for t-C4F9I compared to that for n-C4F9I. The gain of n-C4F9I is found to be equal to that of n-C3F7I. The implications of these findings for space-based solar-pumped lasers are discussed.

  3. Flow tube used to cool solar-pumped laser

    NASA Technical Reports Server (NTRS)

    1968-01-01

    A flow tube has been designed and constructed to provide two major functions in the application of a laser beam for transmission of both sound and video. It maintains the YAG laser at the proper operating temperature of 300 degrees K under solar pumping conditions, and it serves as a pump cavity for the laser crystal.

  4. Solar pumped laser technology options for space power transmission

    NASA Technical Reports Server (NTRS)

    Conway, E. J.

    1986-01-01

    An overview of long-range options for in-space laser power transmission is presented. The focus is on the new technology and research status of solar-pumped lasers and their solar concentration needs. The laser options include gas photodissociation lasers, optically-pumped solid-state lasers, and blackbody-pumped transfer lasers. The paper concludes with a summary of current research thrusts.

  5. Direct solar pumping of semiconductor lasers: A feasibility study

    NASA Technical Reports Server (NTRS)

    Anderson, Neal G.

    1992-01-01

    This report describes results of NASA Grant NAG-1-1148, entitled Direct Solar Pumping of Semiconductor Lasers: A Feasibility Study. The goals of this study were to provide a preliminary assessment of the feasibility of pumping semiconductor lasers in space with directly focused sunlight and to identify semiconductor laser structures expected to operate at the lowest possible focusing intensities. It should be emphasized that the structures under consideration would provide direct optical-to-optical conversion of sunlight into laser light in a single crystal, in contrast to a configuration consisting of a solar cell or storage battery electrically pumping a current injection laser. With external modulation, such lasers could perhaps be efficient sources for intersatellite communications. We proposed specifically to develop a theoretical model of semiconductor quantum-well lasers photopumped by a broadband source, test it against existing experimental data where possible, and apply it to estimating solar pumping requirements and identifying optimum structures for operation at low pump intensities. These tasks have been accomplished, as described in this report of our completed project. The report is organized as follows: Some general considerations relevant to the solar-pumped semiconductor laser problem are discussed in Section 2, and the types of structures chosen for specific investigation are described. The details of the laser model we developed for this work are then outlined in Section 3. In Section 4, results of our study are presented, including designs for optimum lattice-matched and strained-layer solar-pumped quantum-well lasers and threshold pumping estimates for these structures. It was hoped at the outset of this work that structures could be identified which could be expected to operate continuously at solar photoexcitation intensities of several thousand suns, and this indeed turned out to be the case as described in this section. Our project is

  6. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1983-01-01

    Possible types of lasers were surveyed for solar power conversion. The types considered were (1) liquid dye lasers, (2) vapor dye lasers, and (3) nondissociative molecular lasers. These are discussed.

  7. Solar-pumped solid state Nd lasers

    NASA Technical Reports Server (NTRS)

    Williams, M. D.; Zapata, L.

    1985-01-01

    Solid state neodymium lasers are considered candidates for space-based polar-pumped laser for continuous power transmission. Laser performance for three different slab laser configurations has been computed to show the excellent power capability of such systems if heat problems can be solved. Ideas involving geometries and materials are offered as potential solutions to the heat problem.

  8. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1983-01-01

    Metallic vapor lasers of Na2 and Li2 are examined as solar energy converters. The absorbed photons cause transitions to vibrational-rotational levels in an upper electronic state. With broad band absorption the resultant levels can have quantum numbers considerably higher than the upper lasing level. The excited molecule then relaxes to the upper lasing level which is one of the lower vibrational levels in the upper electronic state. The relaxation occurs from collisions, provided the molecule is not quenched into the ground level electronic state. Lasing occurs with a transition to a vibrational level in the lower electronic state. Rough estimates of solar power efficiencies are 1 percent for Na2 and probably a similar figure for Li2. The nondissociative lasers from a family distinct from materials which dissociate to yield an excited atom.

  9. Solar Pumped High Power Solid State Laser for Space Applications

    NASA Technical Reports Server (NTRS)

    Fork, Richard L.; Laycock, Rustin L.; Green, Jason J. A.; Walker, Wesley W.; Cole, Spencer T.; Frederick, Kevin B.; Phillips, Dane J.

    2004-01-01

    Highly coherent laser light provides a nearly optimal means of transmitting power in space. The simplest most direct means of converting sunlight to coherent laser light is a solar pumped laser oscillator. A key need for broadly useful space solar power is a robust solid state laser oscillator capable of operating efficiently in near Earth space at output powers in the multi hundred kilowatt range. The principal challenges in realizing such solar pumped laser oscillators are: (1) the need to remove heat from the solid state laser material without introducing unacceptable thermal shock, thermal lensing, or thermal stress induced birefringence to a degree that improves on current removal rates by several orders of magnitude and (2) to introduce sunlight at an effective concentration (kW/sq cm of laser cross sectional area) that is several orders of magnitude higher than currently available while tolerating a pointing error of the spacecraft of several degrees. We discuss strategies for addressing these challenges. The need to remove the high densities of heat, e.g., 30 kW/cu cm, while keeping the thermal shock, thermal lensing and thermal stress induced birefringence loss sufficiently low is addressed in terms of a novel use of diamond integrated with the laser material, such as Ti:sapphire in a manner such that the waste heat is removed from the laser medium in an axial direction and in the diamond in a radial direction. We discuss means for concentrating sunlight to an effective areal density of the order of 30 kW/sq cm. The method integrates conventional imaging optics, non-imaging optics and nonlinear optics. In effect we use a method that combines some of the methods of optical pumping solid state materials and optical fiber, but also address laser media having areas sufficiently large, e.g., 1 cm diameter to handle the multi-hundred kilowatt level powers needed for space solar power.

  10. Solar-pumped Er,Tm,Ho:YAG laser

    SciTech Connect

    Benmair, R.M.J.; Kagan, J.; Kalisky, Y.; Noter, Y.; Oron, M.; Shimony, Y.; Yogev, A. )

    1990-01-01

    Direct solar illumination was used to pump a 5-mm-diameter 62-mm exposed-length rod of Er,Tm,Ho:YAG to achieve a quasi-cw lasing of the Ho ion at an average power of 12 W. The solar radiation was chopped at a 20% duty cycle to avoid overloading of the cooling system. The peak power output was more than 65 W during the chopper's open times. The slope efficiency is 3.8%, and the threshold input energy is approximately 100 W. The laser was operated for long times (up to hours) while maintaining its performance. This is, to our knowledge, the first directly solar-pumped laser operating at 77 K.

  11. Direct solar pumping of semiconductor lasers: A feasibility study

    NASA Technical Reports Server (NTRS)

    Anderson, Neal G.

    1991-01-01

    The primary goals of the feasibility study are the following: (1) to provide a preliminary assessment of the feasibility of pumping semiconductor lasers in space directly focused sunlight; and (2) to identify semiconductor laser structures expected to operate at the lowest possible focusing intensities. It should be emphasized that the structures under consideration would provide direct optical-to-optical conversion of sunlight into laser light in a single crystal, in contrast to a configuration consisting of a solar cell or battery electrically pumping a current injection laser. With external modulation, such lasers may prove to be efficient sources for intersatellite communications. We proposed to develop a theoretical model of semiconductor quantum-well lasers photopumped by a broadband source, test it against existing experimental data where possible, and apply it to estimating solar pumping requirements and identifying optimum structures for operation for operation at low pump intensities. This report outlines our progress toward these goals. Discussion of several technical details are left to the attached summary abstract.

  12. Highly efficient solar-pumped Nd:YAG laser.

    PubMed

    Liang, Dawei; Almeida, Joana

    2011-12-19

    The recent progress in solar-pumped laser with Fresnel lens and Cr:Nd:YAG ceramic medium has revitalized solar laser researches, revealing a promising future for renewable reduction of magnesium from magnesium oxide. Here we show a big advance in solar laser collection efficiency by utilizing an economical Fresnel lens and a most widely used Nd:YAG single-crystal rod. The incoming solar radiation from the sun is focused by a 0.9 m diameter Fresnel lens. A dielectric totally internally reflecting secondary concentrator is employed to couple the concentrated solar radiation from the focal zone to a 4 mm diameter Nd:YAG rod within a conical pumping cavity. 12.3 W cw laser power is produced, corresponding to 19.3 W/m(2) collection efficiency, which is 2.9 times larger than the previous results with Nd:YAG single-crystal medium. Record-high slope efficiency of 3.9% is also registered. Laser beam quality is considerably improved by pumping a 3 mm diameter Nd:YAG rod. PMID:22274224

  13. Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

    SciTech Connect

    Hwang, I.H. . Dept. of Physics); Lee, J.H. . Langley Research Center)

    1991-09-01

    This paper reports on the efficiencies and threshold pump intensities of various solid-state laser materials that have been estimated to compare their performance characteristics as direct solar-pumped CW lasers. Among the laser materials evaluated in this research, alexandrite has the highest slope efficiency of about 12.6%; however, it does not seem to be practical for solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AMO) solar constants and its slope efficiency is about 12% when thermal deformation is completely prevented.

  14. Efficiency and threshold pump intensity of CW solar-pumped solid-state lasers

    NASA Technical Reports Server (NTRS)

    Hwang, In H.; Lee, Ja H.

    1991-01-01

    The authors consider the relation between the threshold pumping intensity, the material properties, the resonator parameters, and the ultimate slope efficiencies of various solid-state laser materials for solar pumping. They clarify the relation between the threshold pump intensity and the material parameters and the relation between the ultimate slope efficiency and the laser resonator parameters such that a design criterion for the solar-pumped solid-state laser can be established. Among the laser materials evaluated, alexandrite has the highest slope efficiency of about 12.6 percent; however, it does not seem to be practical for a solar-pumped laser application because of its high threshold pump intensity. Cr:Nd:GSGG is the most promising for solar-pumped lasing. Its threshold pump intensity is about 100 air-mass-zero (AM0) solar constants and its slope efficiency is about 12 percent when thermal deformation is completely prevented.

  15. Threshold of stimulated Brillouin scattering by use of a solar pumped laser.

    PubMed

    Naftali, Nir; Benmair, Ruth M J; Pe'er, Idit; Yogev, Ammon

    2002-06-20

    What is to our knowledge the first stimulated Brillouin scattering experiment using a high-power low-gain solar pumped laser is presented. A threshold reflectivity of 0.23% was reached when a peak power of 20.7 kW was used at 7.6 GHz. A cw solar pumped laser was Q-switched with an acousto-optic modulator, and the bandwidth was narrowed with an intracavity etalon. A high polarization ratio (>99.4%) was achieved by use of an intracavity configuration. Higher reflectivity values were limited because of the lack of availability of optical switches. PMID:12078683

  16. Analysis of Nd3+:glass, solar-pumped, high-powr laser systems

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; Williams, M. D.

    1989-01-01

    The operating characteristics of Nd(3+):glass lasers energized by a solar concentrator were analyzed for the hosts YAG, silicate glass, and phosphate glass. The modeling is based on the slab zigzag laser geometry and assumes that chemical hardening methods for glass are successful in increasing glass hardness by a factor of 4. On this basis, it was found that a realistic 1-MW solar-pumped laser might be constructed from phosphate glass 4 sq m in area and 2 mm thick. If YAG were the host medium, a 1-MW solar-pumped laser need only be 0.5 sq m in area and 0.5 cm thick, which is already possible. In addition, Nd(3+) doped glass fibers were found to be excellent solar-pumped laser candidates. The small diameter of fibers eliminates thermal stress problems, and if their diameter is kept small (10 microns), they propagate a Gaussian single mode which can be expanded and transmitted long distances in space. Fiber lasers could then be used for communications in space or could be bundled and the individual beams summed or phase-matched for high-power operation.

  17. Solar-pumped Nd:Cr:GSGG parallel array laser

    NASA Astrophysics Data System (ADS)

    Thompson, George A.; Krupkin, V.; Yogev, Amnon; Oron, Moshe

    1992-12-01

    A compact, parallel array of three Nd:Cr:GSGG laser rods is used to construct a quasi-CW laser. The array is pumped by concentrated solar light and is mounted in a single concentrator. The three laser rods use a common pair of laser mirrors to define the optical resonator. The three laser beams are not coherently coupled in these experiments. The simplicity of the design, and its reasonable stability in terms of vibration and optical misalignment, suggest that the design may be scalable for higher power.

  18. Intensity and absorbed-power distribution in a cylindrical solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Williams, M. D.

    1984-01-01

    The internal intensity and absorbed-power distribution of a simplified hypothetical dye laser of cylindrical geometry is calculated. Total absorbed power is also calculated and compared with laboratory measurements of lasing-threshold energy deposition in a dye cell to determine the suitability of solar radiation as a pump source or, alternatively, what modifications, if any, are necessary to the hypothetical system for solar pumping.

  19. Threshold pump power of a solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Kim, Kyung C.; Kim, Kyong H.

    1988-01-01

    Threshold solar power for dye laser pumping has been determined by measuring the gain of a rhodamine 6G dye laser amplifier at various solar-simulated irradiances on an amplifier cell. The measured threshold was 20,000 solar constants (2.7 kW/sq cm) for the dye volume of 2 x 5 x 40 cu mm and the optimum dye concentration of 0.001 M. The threshold is about one-third of that achievable with a high-intensity solar concentrator.

  20. Kinetic modeling of an IBr solar pumped laser

    NASA Technical Reports Server (NTRS)

    Harries, W. L.; Meador, W. E.

    1983-01-01

    The possibility of using an IBr laser as a solar-energy converter is examined theoretically, and reasons for its choice are given. Broadband absorption results in dissociation with the formation of excited metastable Br atoms, some of which then lase to the ground state Br. The ground state is depopulated by three-body recombination and, more importantly, by exchange reactions which more than compensate for the high quenching in heteronuclear halogen systems. Kinetic modeling indicates lasing is possible in the pulsed mode and possibly in the steady state with a cooled gas flow system. Temperature effects are discussed. The efficiency of the laser approaches 1.2 percent at optical thicknesses large enough for complete absorption of the photons.

  1. Solar-Pumped TEM₀₀ Mode Nd:YAG laser.

    PubMed

    Liang, Dawei; Almeida, Joana

    2013-10-21

    Here we show a significant advance in solar-pumped laser beam brightness by utilizing a 1.0 m diameter Fresnel lens and a 3 mm diameter Nd:YAG single-crystal rod. The incoming solar radiation is firstly focused by the Fresnel lens on a solar tracker. A large aspheric lens and a 2D-CPC concentrator are then combined to further compress the concentrated solar radiation along the thin laser rod within a V-shaped pumping cavity. 2.3 W cw TEM₀₀ (M² ≤ 1.1) solar laser power is finally produced, attaining 1.9 W laser beam brightness figure of merit, which is 6.6 times higher than the previous record. For multimode operation, 8.1 W cw laser power is produced, corresponding to 143% enhancement in collection efficiency. PMID:24150353

  2. Flashlamp-pumped iodine monobromide laser characteristics

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; De Young, R. J.

    1983-01-01

    The operating characteristics of a flashlamp-pumped IBr laser were investigated to evaluate its suitability for solar-pumped laser applications. A peak power of 350 W/sq cm at 2.7 microns was achieved at 12-torr IBr pressure. At 500-J flashlamp energy, the IBr output saturated; a gain of 0.17% per cm was measured for IBr. Neon was found to be effective for enhancing the recombination of the photodissociation products. With neon as a buffer gas, the laser pulse length was extended to 53 microsec. The termination of the laser pulse, within the flashlamp pulse, is thought to be due to the temperature rise in the gas. Increasing the IBr initial temperature decreased the lasing output. At 300 C, output dropped to approximately one-half the room temperature value. The dominant quencher is thought to be atomic iodine. IBr was found to couple better to the flashlamp energy than C3F7I.

  3. A path to practical Solar Pumped Lasers via Radiative Energy Transfer

    SciTech Connect

    Reusswig, Philip D.; Nechayev, Sergey; Scherer, Jennifer M.; Hwang, Gyu Weon; Bawendi, Moungi G.; Baldo, Marc. A.; Rotschild, Carmel

    2015-10-05

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd 3+ -doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 23 W-cm-2, or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.

  4. A path to practical Solar Pumped Lasers via Radiative Energy Transfer

    DOE PAGESBeta

    Reusswig, Philip D.; Nechayev, Sergey; Scherer, Jennifer M.; Hwang, Gyu Weon; Bawendi, Moungi G.; Baldo, Marc. A.; Rotschild, Carmel

    2015-10-05

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd 3+ -doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CWmore » solar lasing threshold of 23 W-cm-2, or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns.« less

  5. A path to practical Solar Pumped Lasers via Radiative Energy Transfer

    PubMed Central

    Reusswig, Philip D.; Nechayev, Sergey; Scherer, Jennifer M.; Hwang, Gyu Weon; Bawendi, Moungi G.; Baldo, Marc. A.; Rotschild, Carmel

    2015-01-01

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd3+-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 23 W-cm−2, or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns. PMID:26434400

  6. A path to practical Solar Pumped Lasers via Radiative Energy Transfer.

    PubMed

    Reusswig, Philip D; Nechayev, Sergey; Scherer, Jennifer M; Hwang, Gyu Weon; Bawendi, Moungi G; Baldo, Marc A; Rotschild, Carmel

    2015-01-01

    The optical conversion of incoherent solar radiation into a bright, coherent laser beam enables the application of nonlinear optics to solar energy conversion and storage. Here, we present an architecture for solar pumped lasers that uses a luminescent solar concentrator to decouple the conventional trade-off between solar absorption efficiency and the mode volume of the optical gain material. We report a 750-μm-thick Nd(3+)-doped YAG planar waveguide sensitized by a luminescent CdSe/CdZnS (core/shell) colloidal nanocrystal, yielding a peak cascade energy transfer of 14%, a broad spectral response in the visible portion of the solar spectrum, and an equivalent quasi-CW solar lasing threshold of 23 W-cm(-2), or approximately 230 suns. The efficient coupling of incoherent, spectrally broad sunlight in small gain volumes should allow the generation of coherent laser light from intensities of less than 100 suns. PMID:26434400

  7. Solar Pumped Solid State Lasers for Space Solar Power: Experimental Path

    NASA Technical Reports Server (NTRS)

    Fork, Richard L.; Carrington, Connie K.; Walker, Wesley W.; Cole, Spencer T.; Green, Jason J. A.; Laycock, Rustin L.

    2003-01-01

    We outline an experimentally based strategy designed to lead to solar pumped solid state laser oscillators useful for space solar power. Our method involves solar pumping a novel solid state gain element specifically designed to provide efficient conversion of sunlight in space to coherent laser light. Kilowatt and higher average power is sought from each gain element. Multiple such modular gain elements can be used to accumulate total average power of interest for power beaming in space, e.g., 100 kilowatts and more. Where desirable the high average power can also be produced as a train of pulses having high peak power (e.g., greater than 10(exp 10 watts). The modular nature of the basic gain element supports an experimental strategy in which the core technology can be validated by experiments on a single gain element. We propose to do this experimental validation both in terrestrial locations and also on a smaller scale in space. We describe a terrestrial experiment that includes diagnostics and the option of locating the laser beam path in vacuum environment. We describe a space based experiment designed to be compatible with the Japanese Experimental Module (JEM) on the International Space Station (ISS). We anticipate the gain elements will be based on low temperature (approx. 100 degrees Kelvin) operation of high thermal conductivity (k approx. 100 W/cm-K) diamond and sapphire (k approx. 4 W/cm-K). The basic gain element will be formed by sequences of thin alternating layers of diamond and Ti:sapphire with special attention given to the material interfaces. We anticipate this strategy will lead to a particularly simple, robust, and easily maintained low mass modelocked multi-element laser oscillator useful for space solar power.

  8. Performance of passive Q-switched solar-pumped high-power Nd:YAG lasers

    NASA Astrophysics Data System (ADS)

    Noter, Yoram; Naftali, Nir; Pe'er, Idit L.; Yogev, Amnon; Lando, Mordechai; Shimony, Yehoshua

    1997-09-01

    Q-switched, solar-pumped, high power Nd:YAG lasers are attractive for a variety of applications requiring high instantaneous peak power density. The Q-switching can be obtained by an acousto-optic, electro-optic or passive device. Passive Q-switching seems an excellent choice for space as well as for other applications since it neither requires an external driver nor an electrical power supply. In recent years Cr+4:YAG single crystals were extensively used as passive Q-switches for flashlamp-pumped high power Nd:YAG lasers, demonstrating their superior thermal superior thermal characteristics and durability. In this work we report the first operation of passive Q- switched, solar-pumped, high power Nd:YAG lasers. The concentrated solar energy for he optical pumping of the laser was obtained by a 3-stage combination of imaging and non-imaging optics. It included: i) Weizmann Institute solar tower heliostats, ii) 3D compound parabolic concentrator, and iii) 2D compound parabolic concentrator in which the laser rod was placed. 72 mm long laser rods with either 3 mm or 4 mm diameter were used. The passive Q-switch was made from a Cr$=+4):YAG single crystal having a low- intensity transmission of 72 percent at 1.06 (mu) . Its rear surface was coated by a high reflectivity coating, serving as the rear mirror of the cavity. Output coupling mirrors with various reflectivities were used. The passive Q-switch demonstrated excellent durability and reliability during all the experiments. Repetition rates of 6-39 kHz were measured, showing higher repetition rates at higher laser power levels. The pulses demonstrated shorter full width at half maximum (FWHM) time for higher laser power elves, and the FWHM time range was 190-310 nsec. The maximal measured average power was 14 W. Thermal lensing was measured as a function of the absorbed solar power in the laser rod. It is estimated that laser peak power densities of approximately 100 kW/cm2 were achieved in the experiments. It is

  9. Identification and properties of molecular systems of potential use in solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Micha, D. A.; Oehrn, N. Y.

    1985-01-01

    The concepts and computational tools of theortical chemistry are used to investigate molecular properties needed in direct solar-pumped lasers. Compounds of the type RR'CXY, with R and R' organic groups, and X and Y halide atoms were identified as likely candidates because of their highly enhanced absorption coefficients over compounds with a single halide atom. The use of a combination of vibrational excitation followed by electronic excitation to enhance quantum yields at certain wavelengths is indicated. A self-consistent eikonal approximation to state-to-state transitions was tested for CH3I and is useful for other problems involving electronic energy and charge transfer. An approach to calculate potential energy surfaces and transition dipoles was developed which is based on the generation of eigenstates of the nonrelativisitc Hamiltonian followed by incorporation of the spin-orbit coupling by configuration interaction.

  10. Design of high-brightness TEM00-mode solar-pumped laser for renewable material processing

    NASA Astrophysics Data System (ADS)

    Liang, D.; Almeida, J.

    2014-08-01

    The conversion of sunlight into laser light by direct solar pumping is of ever-increasing importance because broadband, temporally constant, sunlight is converted into laser light, which can be a source of narrowband, collimated, rapidly pulsed, radiation with the possibility of obtaining extremely high brightness and intensity. Nonlinear processes, such as harmonic generation, might be used to obtain broad wavelength coverage, including the ultraviolet wavelengths, where the solar flux is very weak. The direct excitation of large lasers by sunlight offers the prospect of a drastic reduction in the cost of coherent optical radiation for high average power materials processing. This renewable laser has a large potential for many applications such as high-temperature materials processing, renewable magnesium-hydrogen energy cycle and so on. We propose here a scalable TEM00 mode solar laser pumping scheme, which is composed of four firststage 1.13 m diameter Fresnel lenses with its respective folding mirrors mounted on a two-axis automatic solar tracker. Concentrated solar power at the four focal spots of these Fresnel lenses are focused individually along a common 3.5 mm diameter, 70 mm length Nd:YAG rod via four pairs of second-stage fused-silica spherical lenses and third-stage 2D-CPCs (Compound Parabolic Concentrator), sitting just above the laser rod which is also double-pass pumped by four V-shaped pumping cavities. Distilled water cools both the rod and the concentrators. 15.4 W TEM00 solar laser power is numerically calculated, corresponding to 6.7 times enhancement in laser beam brightness.

  11. Analysis of a 10 megawatt space-based solar-pumped neodymium laser system

    NASA Technical Reports Server (NTRS)

    Kurweg, U. H.

    1984-01-01

    A ten megawatt solar-pumped continuous liquid laser system for space applications is examined. It is found that a single inflatable mirror of 434 m diameter used in conjunction with a conical secondary concentrator is sufficient to side pump a liquid neodymium lasant in an annular tube of 6 m length and 1 m outer and 0.8 m inner diameter. About one fourth of intercepted radiation converging on the laser tube is absorbed and one fifth of this radiation is effective in populating the upper levels. The liquid lasant is flowed through the annular laser cavity at 1.9 m/s and is cooled via a heat exchanger and a large radiator surface comparable in size to the concentrating mirror. The power density of incident light within the lasant of approximately 68 watt/cu cm required for cw operation is exceeded in the present annular configuration. Total system weight corresponds to 20,500 kg and is thus capable of being transported to near Earth orbit by a single shuttle flight.

  12. High-efficiency solar-pumped laser with a grooved Nd:YAG rod.

    PubMed

    Xu, Peng; Yang, Suhui; Zhao, Changming; Guan, Zhu; Wang, Huaxin; Zhang, Yichen; Zhang, Haiyang; He, Tao

    2014-06-20

    We test the performances of a Nd:YAG rod with a grooved sidewall in two solar pumped laser setups. In both cases, a Fresnel lens with a surface of 1.03  m2 is used as the primary solar light concentrator. In the first setup, a ceramic conical cavity is used as the secondary concentrator. Maximum output power of 20.3 W is obtained, corresponding to a slope efficiency of laser output power with respect to focused solar power of 8.34%. In the second setup, a water tube lens is added in a copper conical cavity to further increase the solar energy concentration; from this setup, 27 W output power is obtained, the slope efficiency of laser output power with respect to focused solar power is 9%. In both cases, the performances of the grooved rod are compared with those of an unpolished rod. The efficiency and the beam quality with the grooved rod are superior to those of the unpolished rod. PMID:24979426

  13. Feasibility study of a conical-toroidal mirror resonator for solar-pumped thin-disk lasers

    NASA Astrophysics Data System (ADS)

    Endo, M.

    2007-04-01

    An optical resonator that is suited to a large-scale, space-based solar-pumped solid-state lasers is proposed, and it is studied by numerical simulations. The resonator consists of a conical-toroidal reflector element on which a doughnut-shaped thin-disk active medium is set, and an output coupler. Unlike the ordinary thin-disk lasers, the optical ray of the proposed resonator passes the medium radially. With this arrangement, the resonator can enjoy the benefits of the thin-disk geometry, i. e., good thermal removability and low index gradient, while getting rid of the disadvantages of them as a solar-pumped laser, low round-trip gain and poor beam quality. The output power, beam quality, thermomechanical properties, and alignment stability of the proposed resonator combined with a Nd/Cr codoped GSGG is discussed.

  14. Feasibility study of a conical-toroidal mirror resonator for solar-pumped thin-disk lasers.

    PubMed

    Endo, M

    2007-04-30

    An optical resonator that is suited to a large-scale, space-based solar-pumped solid-state lasers is proposed, and it is studied by numerical simulations. The resonator consists of a conical-toroidal reflector element on which a doughnut-shaped thin-disk active medium is set, and an output coupler. Unlike the ordinary thin-disk lasers, the optical ray of the proposed resonator passes the medium radially. With this arrangement, the resonator can enjoy the benefits of the thin-disk geometry, i. e., good thermal removability and low index gradient, while getting rid of the disadvantages of them as a solar-pumped laser, low round-trip gain and poor beam quality. The output power, beam quality, thermomechanical properties, and alignment stability of the proposed resonator combined with a Nd/Cr codoped GSGG is discussed. PMID:19532804

  15. Spectroscopic properties of Nd, Er codoped glasses for solar pumped fiber lasers

    NASA Astrophysics Data System (ADS)

    Mizuno, Shintaro; Ito, Hiroshi; Hasegawa, Kazuo; Kawai, Hiroyuki; Nasu, Hiroyuki; Hughes, Mark A.; Suzuki, Takenobu; Ohishi, Yasutake

    2011-03-01

    The absorption and fluorescence characteristics of Er doped and Nd, Er codoped fluoride glasses were investigated under illumination of the simulated sunlight, laser or a monochromatic light filtered from a Xe lamp. Er was used as a sensitizing agent enhancing the energy conversion and the emission efficiency of Nd ions in fluoride glass intended for the sunlight excitation. Er doped fluoride glasses showed four emission peaks under simulated sunlight illumination at the wavelengths of 550, 848, 980, and 1530 nm attributed to the electronic transitions of Er3+ ions. The quantum efficiency of the emission from all of the bands had a peak at x = 0.5 mol. % Er and with the maximum of 73 %. The intensity of each emission band showed different ratios for various ErF3 contents. It is expected that concentration quenching of 4S3/2 state is easy to occur with high concentration of ErF3 compared to the other states. The energy transfer from Er to Nd was studied using a monochromatic light illumination which is absorbed by Er3+ ions only. Strong contribution of Er absorption to the 1.05 μm emission of Nd, Er co-doped fluoride glass was observed. Er was confirmed as a suitable sensitizer for the enhanced energy conversion and emission efficiency of Nd ions in ZBLAN glasses which are proposed for highly efficient solar pumped fiber lasers.

  16. Effects of coolant temperature and pump power on the power output of solar-pumped solid state lasers

    NASA Astrophysics Data System (ADS)

    Thompson, George A.; Yogev, Amnon; Reich, A.; Oron, Moshe

    1992-11-01

    The temperature dependence of solar-pumped solid state lasers of Nd:YAG and two types of Nd:Cr:GSGG was studied over the temperature range of +30 to -60 C in a quasi-CW mode. All lasers had higher output powers at -40 C. The Nd:Cr:GSGG laser with a chromium concentration of 2.5 at. pct produced 70 W of power at -40 C, quasi-CW. If extrapolated to true CW operation this is equivalent to 350 W. The temperature dependence of the laser performance is attributed to changes in both the stimulated emission cross section and the resonator configuration.

  17. Systems efficiency and specific mass estimates for direct and indirect solar-pumped closed-cycle high-energy lasers in space

    NASA Technical Reports Server (NTRS)

    Monson, D. J.

    1978-01-01

    Based on expected advances in technology, the maximum system efficiency and minimum specific mass have been calculated for closed-cycle CO and CO2 electric-discharge lasers (EDL's) and a direct solar-pumped laser in space. The efficiency calculations take into account losses from excitation gas heating, ducting frictional and turning losses, and the compressor efficiency. The mass calculations include the power source, radiator, compressor, fluids, ducting, laser channel, optics, and heat exchanger for all of the systems; and in addition the power conditioner for the EDL's and a focusing mirror for the solar-pumped laser. The results show the major component masses in each system, show which is the lightest system, and provide the necessary criteria for solar-pumped lasers to be lighter than the EDL's. Finally, the masses are compared with results from other studies for a closed-cycle CO2 gasdynamic laser (GDL) and the proposed microwave satellite solar power station (SSPS).

  18. Consideration of coordinated solar tracking of an array of compact solar-pumped lasers combined with photovoltaic cells for electricity generation

    NASA Astrophysics Data System (ADS)

    Motohiro, Tomoyoshi; Ichiki, Akihisa; Ichikawa, Tadashi; Ito, Hiroshi; Hasegawa, Kazuo; Mizuno, Shintaro; Ito, Tadashi; Kajino, Tsutomu; Takeda, Yasuhiko; Higuchi, Kazuo

    2015-08-01

    A monochromatic laser light with a photon energy just above the band edge of photovoltaic cells can be converted into electricity with minimal thermal loss. To attain efficient conversion of sunlight to laser light, a coordinated solar tracking system for an array of originally designed compact solar-pumped lasers of 50 mm aperture diameter is being constructed. As for the feasibility of this system, a prototype with a holding capacity of 25 compact solar-pumped lasers has been fabricated. The primary requisite of this system is that the angular accuracy of tracking should be below 1 mrad for all 25 compact solar-pumped lasers to sustain their continuous lasing. To realize this, imperative challenges have been elucidated including thermal expansion under sunlight. A prototype fabricated with its main frame made of Super Invar alloy was found to fulfill the requisite by measurement using a three-dimensional coordinate measuring machine.

  19. Influence of operating temperature on the power, divergence, and stress-induced birefringence in solar-pumped solid state lasers

    NASA Astrophysics Data System (ADS)

    Brauch, U.; Muckenschnabel, J.; Thompson, George A.; Bernstein, Hana; Yogev, Amnon; Reich, A.; Oron, Moshe

    1992-05-01

    The relative performance of solar-pumped Nd:YAG and Nd:Cr:GSGG lasers was evaluated at both 300 and 80 K. Measurements of the slope efficiency and the lasing threshold were made on several lasers containing these crystals. The stress-induced birefringence and the divergence were also studied. The measurements were used to calculate the values of the intrinsic efficiencies and the losses at both temperatures. The possible mechanisms for the observed temperature dependence are discussed. Due to the improved thermal conductivity of the laser crystals at low temperature, all lasers showed significantly improved performance at low temperature. Both the slope efficiencies and the thresholds improved by a factor of 2 to 3 on cooling. The absolute value of the beam quality, and its sensitivity to changes in the resonator configuration or pump power were significantly better at low temperature.

  20. A model for the kinetics of a solar-pumped long path laser experiment

    NASA Technical Reports Server (NTRS)

    Stock, L. V.; Wilson, J. W.; Deyoung, R. J.

    1986-01-01

    A kinetic model for a solar-simulator pumped iodine laser system is developed and compared to an experiment in which the solar simulator output is dispersed over a large active volume (150 cu cm) with low simulator light intensity (approx. 200 solar constants). A trace foreign gas which quenches the upper level is introduced into the model. Furthermore, a constant representing optical absorption of the stimulated emission is introduced, in addition to a constant representing the scattering at each of the mirrors, via the optical cavity time constant. The non-uniform heating of the gas is treated as well as the pressure change as a function of time within the cavity. With these new phenomena introduced into the kinetic model, a best reasonable fit to the experimental data is found by adjusting the reaction rate coefficients within the range of known uncertainty by numerical methods giving a new bound within this range of uncertainty. The experimental parameters modeled are the lasing time, laser pulse energy, and time to laser threshold.

  1. Preliminary design and cost of a 1-megawatt solar-pumped iodide laser space-to-space transmission station

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

    1987-01-01

    A preliminary conceptual design of a space-based solar pumped iodide laser emitting 1 megawatt of laser power for space-to-space power transmission is described. A near parabolic solar collector focuses sunlight onto the t-C4F9I (perfluoro-t butyl iodide) lasant within a transverse flow optical cavity. Using waste heat, a thermal system was designed to supply compressor and auxiliary power. System components were designed with weight and cost estimates assigned. Although cost is very approximate, the cost comparison of individual system components leads to valuable insights for future research. In particular, it was found that laser efficiency was not a dominant cost or weight factor, the dominant factor being the laser cavity and laser transmission optics. The manufacturing cost was approx. two thirds of the total cost with transportation to orbit the remainder. The flowing nonrenewable lasant comprised 20% of the total life cycle cost of the system and thus was not a major cost factor. The station mass was 92,000 kg without lasant, requiring approx. four shuttle flights to low Earth orbit where an orbital transfer vehicle will transport it to the final altitude of 6378 km.

  2. Scalable chemical oxygen - iodine laser

    SciTech Connect

    Adamenkov, A A; Bakshin, V V; Vyskubenko, B A; Efremov, V I; Il'in, S P; Ilyushin, Yurii N; Kolobyanin, Yu V; Kudryashov, E A; Troshkin, M V

    2011-12-31

    The problem of scaling chemical oxygen - iodine lasers (COILs) is discussed. The results of experimental study of a twisted-aerosol singlet oxygen generator meeting the COIL scalability requirements are presented. The energy characteristics of a supersonic COIL with singlet oxygen and iodine mixing in parallel flows are also experimentally studied. The output power of {approx}7.5 kW, corresponding to a specific power of 230 W cm{sup -2}, is achieved. The maximum chemical efficiency of the COIL is {approx}30%.

  3. Perfluoro-n-hexyl iodide as gain media for high power, continuous solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Lee, Ja H.; Tabibi, Bagher M.; Humes, Donald H.; Weaver, Willard R.

    1990-01-01

    A comparative study of CW laser performance with n-C6F13I and n-C3F7I was performed using a 10-W solar-simulator-pumped laser system. The measured output power for n-C6F13I is near 10 W and is comparable to that of n-C3F7I. However, n-C6F13I has the advantages of easy purification and repeated use.

  4. The high-power iodine laser

    NASA Astrophysics Data System (ADS)

    Brederlow, G.; Fill, E.; Witte, K. J.

    The book provides a description of the present state of the art concerning the iodine laser, giving particular attention to the design and operation of pulsed high-power iodine lasers. The basic features of the laser are examined, taking into account aspects of spontaneous emission lifetime, hyperfine structure, line broadening and line shifts, stimulated emission cross sections, the influence of magnetic fields, sublevel relaxation, the photodissociation of alkyl iodides, flashlamp technology, excitation in a direct discharge, chemical excitation, and questions regarding the chemical kinetics of the photodissociation iodine laser. The principles of high-power operation are considered along with aspects of beam quality and losses, the design and layout of an iodine laser system, the scalability and prospects of the iodine laser, and the design of the single-beam Asterix III laser.

  5. Development of a chemical oxygen - iodine laser with production of atomic iodine in a chemical reaction

    SciTech Connect

    Censky, M; Spalek, O; Jirasek, V; Kodymova, J; Jakubec, I

    2009-11-30

    The alternative method of atomic iodine generation for a chemical oxygen - iodine laser (COIL) in chemical reactions with gaseous reactants is investigated experimentally. The influence of the configuration of iodine atom injection into the laser cavity on the efficiency of the atomic iodine generation and small-signal gain is studied. (lasers)

  6. Short-pulse photolytic iodine laser

    NASA Astrophysics Data System (ADS)

    Tate, Ralph F.; Harris, Melvin; Anderson, Brian T.; Hager, Gordon D.

    2000-08-01

    A compact, short pulse photolytic iodine laser (PIL) system designed for use as a source in Raman conversion experiments is described. The single-shot, flashlamp-pumped laser outputs 10 Joules in a 3 microsecond(s) FWHM pulse at a wavelength of 1.315 micrometer and uses n-C3F7I as the renewable laser fuel. Laser design and performance characteristics are presented.

  7. Overview of iodine generation for oxygen-iodine lasers

    NASA Astrophysics Data System (ADS)

    Jirásek, Vít.

    2012-01-01

    A review of the methods for generation of iodine for oxygen-iodine lasers (OIL) is presented. The chemical and physical methods for production of both atomic (AI) and molecular (MI) iodine have been searched in order to improve the efficiency and/or technology of OILs. These trials were motivated by the estimations that a substantial part of singlet oxygen (SO) could be saved with these methods and the onset of the laser active medium will be accelerated. Vapour of MI can be generated by the evaporation of solid or pressurized liquid I2, or synthesized in situ by the reaction of Cl2 with either HI or CuI2. The chemical methods of generation of AI are based on the substitution of I atom in a molecule of HI or ICl by another halogen atom produced usually chemically. The discharge methods include the dissociation of various iodine compounds (organic iodides, I2, HI) in the RF, MW, DC-pulsed or DC-vortex stabilized discharge. Combined methods use discharge dissociation of molecules (H2, F2) to gain atoms which subsequently react to replace AI from the iodine compound. The chemical methods were quite successful in producing AI (up to the 100% yield), but the enhancement of the laser performance was not reported. The discharge methods had been subsequently improving and are today able to produce up to 0.4 mmol/s of AI at the RF power of 500 W. A substantial enhancement of the discharge- OIL performance (up to 40%) was reported. In the case of Chemical-OIL, the enhancement was reported only under the conditions of a low I2/O2 ratio, where the "standard" I2 dissociation by SO is slow. The small-signal gain up to 0.3 %/cm was achieved on the supersonic COIL using the HI dissociated in the RF discharge. Due to the complicated kinetics of the RI-I-I2-SO system and a strong coupling with the gas flow and mixing, the theoretical description of the problem is difficult. It, however, seems that we can expect the major improvement of the OIL performance for those systems, where

  8. Overview of repetitively pulsed photolytic iodine lasers

    NASA Astrophysics Data System (ADS)

    Schlie, L. A. V.

    1996-02-01

    The performance of a repetitively pulsed, 70 joule, closed cycle 1.3 (mu) M photolytic atomic iodine laser with excellent beam quality (BQ equals 1.15) is presented. This BQ was exhibited in the fundamental mode from a M equals 3.1 confocal unstable resonator at a 0.5 Hz repetition rate. A closed cycle scrubber/laser fuel system consisting of a condensative- evaporative section, two Cu wool I2 reactor regions, and an internal turbo-blower enabled the laser to operate very reliably with low maintenance. The fuel system provided C3F7I gas at 10 - 60 torr absent of the photolytic quenching by-product I2. Using a turbo- molecular blower longitudinal flow velocities greater than 10 m/s were achieved through the 150 cm long by 7.5 multiplied by 7.5 cm2 cross sectional photolytic iodine gain region. In addition to the high laser output and excellent BQ, the resulting 8 - 12 microsecond laser pulse had a coherence length greater than 45 meters and polarization extinction ratio better than 100:1. Projections from this pulsed photolytic atomic iodine laser technology to larger energies, higher repetition rates, and variable pulse widths are discussed.

  9. Comparison between the perfomance of Nd:YAG, Nd/Cr:GSGG and Nd/Cr:YAG ceramic lasers with quasi-solar pumping

    NASA Astrophysics Data System (ADS)

    Bouadjemine, R.; Louhibi, D.; Kellou, A.

    2015-01-01

    Recent developments in laser materials, such as Nd/Cr:YAG ceramic with a broad absorption spectrum in the visible, have been applied to achieve highly-efficient and low-cost optical pumping by conventional sources. Our simulator based on the implementation of a mathematical model under Matlab Simulink allowed us to show the correlation between the characteristics of the laser mode of operation (such as Relaxation, Quasi-continuous wave (QCW), Continuous wave, Burst, Q-switched) and the various physical parameters of the oscillator. This model was applied to the Nd:YAG crystal, Nd/Cr:GSGG crystal and Nd/Cr:YAG ceramic. The simulation results demonstrated that Nd/Cr:YAG ceramic is an excellent candidate for solar and quasi-solar pumping, as its pumping efficiency exceeds by a factor of four that of the Nd:YAG crystal medium, and by a factor of two that of Nd/Cr:GSGG crystal. A pumping by a light guide was considered in this simulation.

  10. A model for a continuous-wave iodine laser

    NASA Technical Reports Server (NTRS)

    Hwang, In H.; Tabibi, Bagher M.

    1990-01-01

    A model for a continuous-wave (CW) iodine laser has been developed and compared with the experimental results obtained from a solar-simulator-pumped CW iodine laser. The agreement between the calculated laser power output and the experimental results is generally good for various laser parameters even when the model includes only prominent rate coefficients. The flow velocity dependence of the output power shows that the CW iodine laser cannot be achieved with a flow velocity below 1 m/s for the present solar-simulator-pumped CW iodine laser system.

  11. Laser Induced Fluorescence of the Iodine Ion

    NASA Astrophysics Data System (ADS)

    Hargus, William

    2014-10-01

    Iodine (I2) has been considered as a potential electrostatic spacecraft thruster propellant for approximately 2 decades, but has only recently been demonstrated. Energy conversion efficiency appears to be on par with xenon without thruster modification. Intriguingly, performance appears to exceed xenon at high acceleration potentials. As part of a continuing program for the development of non-intrusive plasma diagnostics for advanced plasma spacecraft propulsion, we have identified the I II 5d5D4 o state as metastable, and therefore containing a reservoir of excited state ions suitable for laser probing. The 5d5D4 o - 6p5P3 transition at 695.878 nm is convenient for diode laser excitation with the 5s5S2 o - 6p5P3 transition at 516.12 nm as an ideal candidate for non-resonant fluorescence collection. We have constructed a Penning type iodine microwave discharge lamp optimized for I II production for table-top measurements. This work demonstrates I II laser-induced fluorescence in a representative iodine discharge and will validate our previous theoretical work based on the limited available historical I II spectral data.

  12. An experimental study of the chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Vagin, N. P.; Karapetian, D. G.; Konoshenko, A. F.; Kriukov, P. G.; Paziuk, V. S.

    The construction of an oxygen-iodine laser with an output power of up to 400 W based on a chemical singlet oxygen generator is reported. The possibility of achieving high outputs using modular design is demonstrated. The possibility of the operation of chemical oxygen-iodine lasers in the pulsed mode is analyzed, and it is shown that, in this mode, such lasers can operate without a low-temperature trap. In addition, the pulsed mode makes it possible to control the lasing pulse length over a wide range. Possible applications of pulsed chemical oxygen-iodine lasers in thermonuclear fusion are briefly discussed.

  13. Solar-simulator-pumped atomic iodine laser kinetics

    NASA Technical Reports Server (NTRS)

    Wilson, H. W.; Raju, S.; Shiu, Y. J.

    1983-01-01

    The literature contains broad ranges of disagreement in kinetic data for the atomic iodine laser. A kinetic model of a solar-simulator-pumped iodine laser is used to select those kinetic data consistent with recent laser experiments at the Langley Research Center. Analysis of the solar-simulator-pumped laser experiments resulted in the following estimates of rate coefficients: for alkyl radical (n-C3F7) and atomic iodine (I) recombination, 4.3 x 10 to the 11th power (1.9) + or - cu cm/s; for n-C3F7I stabilized atomic iodine recombination (I + I) 3.7 x 10 to the -32nd power (2.3) + or -1 cm to the 6th power/s; and for molecular iodine (I2) quenching, 3.1 x 10 to the -11th power (1.6) + or - 1 cu cm/s. These rates are consistent with the recent measurements.

  14. Satellite Power System (SPS) laser studies. Volume 2: Meteorological effects on laser beam propagation and direct solar pumped lasers for the SPS

    NASA Technical Reports Server (NTRS)

    Beverly, R. E., III

    1980-01-01

    The primary emphasis of this research activity was to investigate the effect of the environment on laser power transmission/reception from space to ground. Potential mitigation techniques to minimize the environment effect by a judicious choice of laser operating parameters was investigated. Using these techniques, the availability of power at selected sites was determined using statistical meteorological data for each site.

  15. Investigation of the excited state iodine lifetime in the photodissociation of perfluoroalkyl iodides

    NASA Technical Reports Server (NTRS)

    Cobb, Stephen H.

    1991-01-01

    An evaluation of prospective laser materials for a space-based solar pumped laser system over the past decade has resulted in the identification of the iodine photodissociation laser as that system best suited to solar-pumped high energy operation. The active medium for the solar-pumped iodine photodissociation laser is from the family of perfluoroalkyl iodides. These lasants have the general form C(n)F(2n + 1)I, often abbreviated as RI. These iodides are known to exhibit photodissociaiton of the C-I bond when irradiated by near UV photons. The focus was on the experimental determination of the lifetime of the excited iodine atom following photodissociation of C4F9I, and also to monitor fluorescence from the iodine molecule at 500 nm to determine if I2 is being produced in the process. Photodissociation is achieved using an XeCl excimer laser with an output wavelength of 308 nm. The XeCl beam is focused into the middle of a cylindrical quartz cell containing the lasant. The laser pulse is detected with a fast risetime photomultiplier tube as it exits the cell. Other aspects of the investigation are discussed.

  16. Chemical oxygen-iodine laser with cryosorption vacuum pump

    NASA Astrophysics Data System (ADS)

    Vetrovec, John

    2000-05-01

    In a chemical oxygen-iodine laser (COIL), chemically prepared, gaseous gain medium at 3-10 Torr pressure is drawn through the laser cavity by vacuum suction. Multiple-stage vacuum pumps such as Roots blowers or steam ejectors are typically used to receive and compress the gas flowing from the laser and exhaust it to the atmosphere. The size and weight of such vacuum pumps present a significant challenge to engineering and packaging a transportable COIL system.

  17. Parameters of an electric-discharge generator of iodine atoms for a chemical oxygen-iodine laser

    SciTech Connect

    Azyazov, V N; Vorob'ev, M V; Voronov, A I; Kupryaev, Nikolai V; Mikheev, P A; Ufimtsev, N I

    2009-01-31

    Laser-induced fluorescence is used for measuring the concentration of iodine molecules at the output of an electric-discharge generator of atomic iodine. Methyl iodide CH{sub 3}I is used as the donor of atomic iodine. The fraction of iodine extracted from CH{sub 3}I in the generator is {approx}50%. The optimal operation regimes are found in which 80%-90% of iodine contained in the output flow of the generator was in the atomic state. This fraction decreased during the iodine transport due to recombination and was 20%-30% at the place where iodine was injected into the oxygen flow. The fraction of the discharge power spent for dissociation was {approx}3%. (elements of laser setups)

  18. XeCl laser pumped iodine laser using t-C4F9I

    NASA Technical Reports Server (NTRS)

    Hwang, In Heon; Han, Kwang S.; Lee, Ja H.

    1989-01-01

    An iodine photodissociation laser using t-C4F9I as the active material was pumped by a XeCl laser. An iodine laser output energy of 3 mJ with pulse duration of 25 ns was obtained when the pumping pulse energy was 80 mJ, the iodine pressure was 70 torr, and the reflectance of the output mirror was 85 percent. The high pumping efficiency and low threshold pump power achieved in this experiment are attributable to the high absorption cross section at the pump laser wavelength (308 nm) of the iodide used.

  19. Spectral properties of iodine cells for laser standards

    NASA Astrophysics Data System (ADS)

    Hrabina, Jan; Šarbort, Martin; Acef, Ouali; Du Burck, Frédéric; Chiodo, Nicola; Chea, Erick; Holá, Miroslava; Číp, Ondřej; Lazar, Josef

    2014-12-01

    The main aim of this work is oriented towards preparation and spectral properties evaluation of optical frequency references for laser standards - molecular iodine cells. These references represent the crucial part of setups for practical realization of the meter unit - highly stable laser standards. Furthermore, not only in the most precise laboratory instruments, but also in less demanding interferometric measuring setups the frequency stabilization of the lasers throught the absorption in suitable media ensure the direct traceability to the fundamental standard of length. A set of absorption cells filled with different amounts of molecular iodine (different saturation pressure point of absorption media) was prepared and an agreement between expected and resulting spectral properties of these cells was observed and evaluated. The usage of borosilicate glass instead of common fused silica as a material for cells bodies represents an approach to simplify the manufacturing technology process and also reduces the overall cell costs. A great care must be taken to control/avoid the risk of absorption media contamination by impurities releasing from the cell walls. We introduce an iodine purity and spectral properties evaluation method based on measurement of linewidth of the hyperfine transitions. The proposed method was used for verification of great iodine purity of manufactured cells by comparison of spectral properties with cells traditionally made of fused silica glass with well known iodine purity. The results confirmed a great potential of proposed approaches.

  20. Studies of new media radiation induced laser

    NASA Technical Reports Server (NTRS)

    Han, K. S.; Shiu, Y. J.; Raju, S. R.; Hwang, I. H.; Tabibi, B.

    1984-01-01

    Various lasants were investigated especially, 2-iodohepafluoropropane (i-C3F7I) for the direct solar pumped lasers. Optical pumping of iodine laser was achieved using a small flashlamp. Using i-C3F7I as a laser gain medium, threshold inversion density, small signal gain, and laser performance at the elevated temperature were measured. The experimental results and analysis are presented. The iodine laser kinetics of the C3F7I and IBr system were numerically simulated. The concept of a direct solar-pumped laser amplifier using (i-C3F7I) as the laser material was evaluated and several kinetic coefficients for i-C3F7I laser system were reexamined. The results are discussed.

  1. Molecular Iodine Fluorescence Using a Green Helium-Neon Laser

    ERIC Educational Resources Information Center

    Williamson, J. Charles

    2011-01-01

    Excitation of molecular iodine vapor with a green (543.4 nm) helium-neon laser produces a fluorescence spectrum that is well suited for the upper-level undergraduate physical chemistry laboratory. Application of standard evaluation techniques to the spectrum yields ground electronic-state molecular parameters in good agreement with literature…

  2. Laser-induced fluorescence method for on-line molecular isotopologues of iodine-127, iodine-129, iodine-131 detected in gaseous media using a tunable diode laser

    NASA Astrophysics Data System (ADS)

    Kireev, S. V.; Shnyrev, S. L.; Sobolevsky, I. V.

    2016-06-01

    The letter reports on the development of a laser-induced fluorescence method for on-line selective measurement of 127I2, 129I2, 131I2, 129I127I, 127I131I, 129I131I isotopologue concentrations in gaseous media. The method is based on the excitation of molecular iodine isotopologues’ fluorescence by tunable diode laser (632–637 nm) radiation at three or four wavelengths corresponding to the 127I2, 131I2, 129I127I, 129I131I absorption line centers. Boundary relations for concentrations of simultaneously measured iodine isotopologues is about 10‑5–10‑6.

  3. Laser-initiated iodine radical chemistry in single microdroplets

    NASA Astrophysics Data System (ADS)

    Vaughn, Bartholomew S.; Tracey, Phillip J.; Trevitt, Adam J.

    2012-11-01

    Iodine radical reactions in single free-falling microdroplets of iodododecane, initiated using UV laser photolysis, are probed using Raman spectroscopy. Stimulated Raman spectra, with 532 nm laser excitation, are recorded at varying time delays from the UV pulse. I atom recombination reactions lead to I2 that changes the optical properties of the microdroplet ultimately quenching the Raman signal. This quenching is observed over ˜10 ns, which is about the time resolution of the two-laser experiment. Although the kinetics are too rapid to be measured in current laser configuration, it demonstrates that radical kinetics can be followed in single microdroplets.

  4. Iodine photodissociation laser with an intracavity space - time light modulator

    SciTech Connect

    Kachalin, G N; Pevny, S N; Pivkin, A N; Safronov, A S

    2012-08-31

    A scheme of an iodine laser with two different intracavity space - time modulators based on electrooptic PLZT ceramics is experimentally studied. It is shown that lasing can occur in different angular directions with the use of both modulators. The output laser energy is 10 mJ with a pulse duration of 200 {mu}s and a beam divergence of 6.3 Multiplication-Sign 10{sup -4} rad. The laser field of view (5.1 Multiplication-Sign 10{sup -3} rad) consists of a discrete set of 8 Multiplication-Sign 8 directions. (control of laser radiation parameters)

  5. Dissociation of molecular iodine in RF discharge for oxygen-iodine lasers

    NASA Astrophysics Data System (ADS)

    Jirásek, V.; Schmiedberger, J.; Čenský, M.; Kodymová, J.

    2012-04-01

    The dissociation of molecular iodine in 40 MHz-RF discharge was studied experimentally. This generation of atomic iodine is aimed at use in oxygen-iodine lasers. The discharge was ignited in a mixture of I2 + buffer gas fast-flowing through the cylindrical chamber and the discharge products were injected into a supersonic flow of nitrogen. The atomic iodine number density was measured in a low-pressure cavity after mixing with nitrogen and the dissociation fraction was calculated related to the input I2 flow rate. The dissociation fraction of 46.2% was achieved at 0.22 mmol/s of I2 and 7 mmol/s of Ar and RF power of 500 W. Argon and helium were used as a buffer gas; discharge stability and dissociation efficiency were better with argon. At the I2 flow rate corresponding to the operation of a 1 kW chemical oxygen-iodine laser, the dissociation fraction was about 20%. The dissociation efficiency (the fraction of absorbed energy used for the dissociation) significantly decreased with increasing in the specific energy. At a reasonable I2 flow rate (0.32 mmol/s), the maximum achieved efficiency was 8.5% and the corresponding energy cost was 8.9 eV per dissociating of one I2 molecule. The input energy of more than 3 kJ per 1 mmol of I2 is needed for dissociating at least 50% of I2. The obtained dependencies on the gas flow rates infer a good chance for scaling-up of the tested RF discharge generator for the intended application.

  6. Second harmonic generation of chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Miura, Noriaki; Mese, Norimichi; Yoshino, Satoru; Uchiyama, Taro

    1993-05-01

    Intracavity second harmonic generation of chemical oxygen iodine laser utilizing LiB3O5 crystal has been studied. A chemical oxygen iodine laser of which the fundamental maximum output power is 3 W in TEM00 mode with the Cl2 flow rate of 300 mmol/min is used. Obtained total second harmonic power is a maximum of about 6 W. Therefore, we could estimate that the effective extraction efficiency is 200%. It is thought that the latter is above 100% due to the condition that the output coupling for the fundamental beam is not optimum. And applying the result of a fundamental laser power measurement, the internal conversion efficiency is estimated at 0.29%.

  7. On a new method for chemical production of iodine atoms in a chemical oxygen-iodine laser

    SciTech Connect

    Andreeva, Tamara L; Kuznetsova, S V; Maslov, A I; Sorokin, Vadim N

    2004-11-30

    A new method is proposed for generating iodine atoms in a chemical oxygen-iodine laser. The method is based on a branched chain reaction of dissociation of the alkyl iodide CH{sub 3}I in a medium of singlet oxygen and chlorine. (active media)

  8. Laser-induced iodine desorption from impregnated polystyrene

    NASA Astrophysics Data System (ADS)

    Torres-Filho, A.; Leite, N. F.; Miranda, L. C. M.; Stempniak, R. A.

    1989-07-01

    The Ar+ laser-stimulated desorption of iodine molecules from an impregnated polystyrene film was investigated. The photoprocess induces a color change (from red to the transparent) and leaves in the film a marked print, which is related to the laser beam characteristics. The experimental data was fitted using a set of differential equations relating the time dependence of the film temperature and absorption coefficient. At low-power levels (<25 mW), the time evolution of the laser transmitted power could be well matched to the experimental data. The wavelength dependence of the marking process was also studied and the relative contribution of photodissociative and photothermal processes was inferred.

  9. Iodine

    MedlinePlus

    ... of iodine are POSSIBLY UNSAFE. Adults should avoid prolonged use of doses higher than 1100 mcg per ... enlarged thyroid gland (goiter), or a thyroid tumor: Prolonged use or high doses of iodine might make ...

  10. Iodine

    MedlinePlus

    ... 6 weeks increases the healing rate. Also, applying povidone-iodine in addition to compression seems help heal ... Catheter-related infection. Some evidence suggests that applying povidone-iodine reduces the risk of blood stream infections ...

  11. Iodine

    MedlinePlus

    ... the amount depends on the iodine in the soil where they grew and in any fertilizer that ... babies. People living in regions with iodine-deficient soils who eat mostly local foods. These soils produce ...

  12. Iodine

    USGS Publications Warehouse

    Krukowski, S.T.

    2006-01-01

    In descending order, Chile, Japan and the United States have the largest iodine reserves. Chile produces iodine from iodate minerals while Japan and the United States produce it from sodium iodide solutions found in underground iodide solutions. Iodine is also produced from subterranean brines in Azerbaijan, Russia, Turkmenista, Indonesia and Uzbekistan. In 2005, iodine prices increased sharply to US$19 to US$23 then leveled off at US$23 to US$25.

  13. Discharge formation systems for generating atomic iodine in a pulse-periodic oxygen–iodine laser

    SciTech Connect

    Aksinin, V I; Kazantsev, S Yu; Kononov, I G; Podlesnykh, S V; Firsov, K N; Antsiferov, S A; Velikanov, S D; Gerasimov, A Yu; Gostev, I V; Kalinovskii, V V; Konovalov, V V; Mikhalkin, V N; Sevryugin, I V

    2014-01-31

    Generation characteristics of a pulse-periodic oxygen–iodine laser with the electro-discharge production of atomic iodine were compared with inductively stabilised edged or anisotropic- resistive cathodes used for ignition of the volume discharge. The discharge was initiated by the radiation of a barrier discharge from the side of a grid anode. It was found that at equal specific electrical energy depositions to the gas-discharge plasma, the system with the anisotropic-resistive cathode provides a more stable and uniform volume discharge with the possibility of varying the composition and pressure of working mixtures over a wide range and a greater specific extraction of laser energy is observed (up to 2.4 J L{sup -1}). At a high pulse repetition rate of laser pulses (50 – 100 Hz) and long duration of the pulse trains (longer than a minute) the surface of anisotropic-resistive cathode became eroded. (laser applications and other topics in quantum electronics)

  14. Nuclear-driven flashlamp pumping of the atomic iodine laser

    SciTech Connect

    Miley, G.H.

    1992-03-01

    This report is a study of the atomic iodine laser pumped with nuclear- excited XeBr fluorescence. Preliminary experiments, conducted in the TRIGA reactor investigated the fluorescence of the excimer XeBr under nuclear pumping with {sup 10}B and {sup 3}He, for use as a flashlamp gas to stimulate the laser. These measurements included a determination of the fluorescence efficiency (light emitted in the wavelength region of interest, divided by energy deposited in the gas) of XeBr under nuclear pumping, with varying excimer mixtures. Maximum fluorescence efficiencies were approximately 1%. In order to better understand XeBr under nuclear excitation, a kinetics model of the system was prepared. The model generated the time-dependant concentrations of 20 reaction species for three pulse sizes, a TRIGA pulse, a fast burst reactor pulse, and an e-beam pulse. The modeling results predicted fluorescence efficiencies significantly higher (peak efficiencies of approximately 10%) than recorded in the fluorescence experiments. The cause of this discrepancy was not fully determined. A ray tracing computer model was also prepared to evaluate the efficiency with which nuclear-induced fluorescence generated in one cavity of a laser could be coupled into another cavity containing an iodine lasant. Finally, an experimental laser cell was constructed to verify that nuclear-induced XeBr fluorescence could be used to stimulate a laser. Lasing was achieved at 1.31 micron in the TRIGA using C{sub 3}F{sub 7}I, a common iodine lasant. Peak laser powers were approximately 20 mW. Measured flashlamp pump powers at threshold agreed well with literature values, as did lasant pressure dependency on laser operation.

  15. XeCl laser pumped iodine laser using t-C4F9I

    NASA Technical Reports Server (NTRS)

    Hwang, In Heon; Han, Kwang S.

    1989-01-01

    An iodine photodissociation laser using t-C4F9I as the active material was pumped by an XeCl laser. An iodine laser output energy of 3 mJ with pulse duration of 25 ns was obtained when the pumping pulse energy was 80 mJ, the iodide pressure was 70 torr, and the reflectance of the output mirror was 85 percent. The high pumping efficiency and low threshold pump power achieved in this experiment are attributable to the high absorption cross section at the pump laser wavelength (308 nm) of the iodide used.

  16. Energy transfer efficiency from Cr(3+) to Nd(3+) in solar-pumped laser using transparent Nd/Cr:Y(3)Al(5)O(12) ceramics.

    PubMed

    Hasegawa, Kazuo; Ichikawa, Tadashi; Mizuno, Shintaro; Takeda, Yasuhiko; Ito, Hiroshi; Ikesue, Akio; Motohiro, Tomoyoshi; Yamaga, Mitsuo

    2015-06-01

    We report energy transfer efficiency from Cr3+ to Nd3+ in Nd (1.0 at.%)/Cr (0.4 at.%) co-doped Y3Al5O12 (YAG) transparent ceramics in the laser oscillation states. The laser oscillation has performed using two pumping lasers operating at 808 nm and 561 nm; the former pumps Nd3+ directly to create the 1064 nm laser oscillation, whereas the latter assists the performance via Cr3+ absorption and sequential energy transfer to Nd3+. From the laser output power properties and laser mode analysis, the energy transfer efficiency was determined to be around 65%, which is close to that obtained from the spontaneous Nd3+ emission. PMID:26072876

  17. Excited states in the active media of oxygen - iodine lasers

    SciTech Connect

    Azyazov, V N

    2009-11-30

    A review of investigations of kinetic processes in active media oxygen - iodine lasers (OILs) performed in the last decade is presented. The mechanisms of pumping and quenching of electronically and vibrationally excited O{sub 2} and I{sub 2} molecules are considered, and dissociation mechanisms of I{sub 2} in the active medium of the OIL are analysed. The values of kinetic constants of processes proceeding in the active media of OILs are recommended. (review)

  18. Development of the electric discharge oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Carroll, David L.; Verdeyen, Joseph T.; King, Darren M.; Palla, Andrew D.; Laystrom, Julia K.; Benavides, Gabriel F.; Zimmerman, Joseph W.; Woodard, Brian S.; Solomon, Wayne C.

    2007-05-01

    In the hybrid electric discharge Oxygen-Iodine laser (ElectricOIL), the desired O II(a1Δ) is produced using a low-to-medium pressure electric discharge. The discharge production of atomic oxygen, ozone, and other excited species adds higher levels of complexity to the post-discharge kinetics which are not encountered in a classic purely chemical O II(a1Δ) generation system. Experimental studies over the past six years using electric discharges have demonstrated O II(a) yields greater than 20%, gain, and cw laser power. Several modeling studies have also been performed for ElectricOIL and similar systems. As the development of this type of iodine laser continues, the roles of oxygen atoms and NO/NO II are found to be very significant in both the discharge region and downstream of the discharge region. A series of O II(1Δ) emission, I* emission, O-atom titrations, gain, and O II(1Δ) yield, NO II* emission, and laser power measurements have been taken to explore the complex phenomena that are being observed. As the overall system is better understood improvements are being made in laser power and efficiency.

  19. Injectant mole-fraction imaging in compressible mixing flows using planar laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Abbitt, John D., III; Mcdaniel, James C.

    1989-01-01

    A technique is described for imaging the injectant mole-fraction distribution in nonreacting compressible mixing flow fields. Planar fluorescence from iodine, seeded into air, is induced by a broadband argon-ion laser and collected using an intensified charge-injection-device array camera. The technique eliminates the thermodynamic dependence of the iodine fluorescence in the compressible flow field by taking the ratio of two images collected with identical thermodynamic flow conditions but different iodine seeding conditions.

  20. Theoretical studies of solar-pumped lasers

    NASA Technical Reports Server (NTRS)

    Harries, Wynford L.

    1988-01-01

    The investigation of stimulated emission causing transitions from the B(1) pi sub u state of sodium to the overlapping 2(1) sigma(+) sub g electronic state has been continued. A new method of estimating the Franck-Condon factors has been developed which instead of fitting the molecular potential curves with Morse functions, estimates the V(r) dependence by interpolation from given potential curves. The results for the sum of the rates from one vibrational level in the upper state to all the levels in the lower state show good agreement with the previous method, implying that curve crossing by stimulated emission due to photons from the oven is an important mechanism in sodium.

  1. Theoretical studies of solar-pumped lasers

    NASA Astrophysics Data System (ADS)

    Harries, Wynford L.

    1988-06-01

    The investigation of stimulated emission causing transitions from the B(1) pi sub u state of sodium to the overlapping 2(1) sigma(+) sub g electronic state has been continued. A new method of estimating the Franck-Condon factors has been developed which instead of fitting the molecular potential curves with Morse functions, estimates the V(r) dependence by interpolation from given potential curves. The results for the sum of the rates from one vibrational level in the upper state to all the levels in the lower state show good agreement with the previous method, implying that curve crossing by stimulated emission due to photons from the oven is an important mechanism in sodium.

  2. Threshold kinetics of a solar-simulator-pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Lee, Y.; Weaver, W. R.; Humes, D. H.; Lee, J. H.

    1984-01-01

    A model of the chemical kinetics of the n-C3F7I solar-simulator-pumped iodine laser is utilized to study the major kinetic processes associated with the threshold behavior of this experimental system. Excited-state diffusion to the cell wall is the dominant limiting factor below 5 torr. Excited-state diffusion to the cell wall is the dominant limiting factor below 5 torr. Excited-state recombination with the alkyl radical and quenching by the parent gas control threshold at higher pressures. Treatment of the hyperfine splitting and uncertainty in the pressure broadening are important factors in fixing the threshold level. In spite of scatter in the experimental data caused by instabilities in the simulator high-pressure high-pressure arc, reasonable agreement is achieved between the model and experiment. Model parameters arrived at are within the uncertainty range of values found in the literature.

  3. Mechanism of dark decomposition of iodine donor in the active medium of a pulsed chemical oxygen - iodine laser

    SciTech Connect

    Andreeva, Tamara L; Kuznetsova, S V; Maslov, A I; Sorokin, Vadim N

    2002-06-30

    A scheme is proposed that describes the dark decomposition of iodide - the donor of iodine - and the relaxation of singlet oxygen in the chlorine-containing active medium of a pulsed chemical oxygen - iodine laser (COIL). For typical compositions of the active media of pulsed COILs utilising CH{sub 3}I molecules as iodine donors, a branching chain reaction of the CH{sub 3}I decomposition accompanied by the efficient dissipation of singlet oxygen is shown to develop even at the stage of filling the active volume. In the active media with CF{sub 3}I as the donor, a similar chain reaction is retarded due to the decay of CF{sub 3} radicals upon recombination with oxygen. The validity of this mechanism is confirmed by a rather good agreement between the results of calculations and the available experimental data. The chain decomposition of alkyliodides accompanied by an avalanche production of iodine atoms represents a new way of efficient chemical production of iodine for a COIL. (active media)

  4. Gain and temperature in a slit nozzle supersonic chemical oxygen-iodine laser with transonic and supersonic injection of iodine

    NASA Astrophysics Data System (ADS)

    Rosenwaks, Salman; Barmashenko, Boris D.; Bruins, Esther; Furman, Dov; Rybalkin, Victor; Katz, Arje

    2002-05-01

    Spatial distributions of the gain and temperament across the flow were studied for transonic and supersonic schemes of the iodine injection in a slit nozzle supersonic chemical oxygen-iodine laser as a function of the iodine and secondary nitrogen flow rate, jet penetration parameter and gas pumping rate. The mixing efficiency for supersonic injection of iodine is found to be much larger than for transonic injection, the maximum values of the gain being approximately 0.65 percent/cm for both injection schemes. Measurements of the gain distribution as a function of the iodine molar flow rate nI2 were carried out. For transonic injection the optimal value of nI2 at the flow centerline is smaller than that at the off axis location. The temperature is distributed homogeneously across the flow, increasing only in the narrow boundary layers near the walls. Opening a leak downstream of the cavity in order to decease the Mach number results in a decrease of the gain and increase of the temperature. The mixing efficiency in this case is much larger than for closed leak.

  5. Investigation of laser-induced iodine fluorescence for the measurement of density in compressible flows

    NASA Technical Reports Server (NTRS)

    Mcdaniel, J. C., Jr.

    1982-01-01

    Laser induced fluorescence is an attractive nonintrusive approach for measuring molecular number density in compressible flows although this technique does not produce a signal that is directly related to the number density. Saturation and frequency detuned excitation are explored as means for minimizing the quenching effect using iodine as the molecular system because of its convenient absorption spectrum. Saturation experiments indicate that with available continuous wave laser sources of Gaussian transverse intensity distribution only partial saturation could be achieved in iodine at the pressures of interest in gas dynamics. Using a fluorescence lineshape theory, it is shown that for sufficiently large detuning of a narrow bandwidth laser from a molecular transition, the quenching can be cancelled by collisional broadening over a large range of pressures and temperatures. Experimental data obtained in a Mach 4.3 underexpanded jet of nitrogen seeded with iodine for various single mode argon laser detunings from a strong iodine transition at 5145 A are discussed.

  6. Assessment of beam intensity profiles in an iodine laser using optical fibers

    NASA Astrophysics Data System (ADS)

    Raffo, C. A.; Rebollo, M. A.; Doti, R.

    1985-05-01

    A method has been developed for measuring the spatial profile of the output beam of an iodine laser at 1.315 μm, which requires only using two optical fibers, one for collecting a reference signal and the other for detecting the laser intensity at a given point of the wavefront. The precision is sufficient for laser engineering purposes.

  7. LASERS: Iodine laser pumped by light from a shock front created by detonating an explosive

    NASA Astrophysics Data System (ADS)

    Arzhanov, V. P.; Borovich, Boris L.; Zuev, V. S.; Kazanskiĭ, V. M.; Katulin, V. A.; Kirillov, G. A.; Kormer, S. B.; Kuratov, Yu V.; Kuryapin, A. I.; Nosach, O. Yu; Sinitsyn, M. V.; Stoĭlov, Yu Yu

    1992-02-01

    The results are presented of investigations, performed in 1965-1966, of a pulsed photodissociation iodine laser utilizing CF3I and C3F7I molecules and pumped by light from a shock front created by detonating an explosive charge. Such lasers were found to possess a unique combination of high output energy and high pulse power. Two types of laser were studied. In one of them the active medium was pumped by light from a shock wave in xenon, and in the other a shock wave propagated through a mixture of the active medium and a rare gas. The energy characteristics of the second type of laser were found to be considerably higher than those of the first type. The laser pulse radiation enegy reached ~100 J with an average power of ~15 MW.

  8. The research of Iodine pool pressure of chemical oxygen-iodine laser in non-equilibrium condition and its automatic control system design

    NASA Astrophysics Data System (ADS)

    Zhou, Songqing; Qu, Pubo; Ren, Weiyan

    2013-05-01

    In the working process of chemical oxy-iodigenne laser(COIL), the change of iodine pool pressure is complicated. As a result, it causes some mis-judgements, such as the damage of heater and the leakage of iodine steam. Further more, when the heater electric circuit is in a single working status, and after the heater switch is on or off, there exists a buffer time for the stabilization of iodine pool pressure, which is a relatively long time, and the minimum buffer pressure exceeds to 19 torr . Of course, it increases the preparing time for steady operation of laser, and reduces the quality of laser beam. In this paper, we study the iodine pool pressure of COIL in non-equilibrium condition, and analyze the mutation and the serious buffer phenomenon of iodine steam pressure. At the same time, we design an automatic control system for iodine pool pressure, which consists of five modules, such as data collection, automatic control, manual control, heater electric circuit, and the setting and display of pressure. This system uses two kinds of heater electric circuits, in this way, the serious buffer phenomenon of iodine pool pressure is effectively avoided. As a result, the maximal buffer pressure reduces to 4 torr, this makes sure that the iodine steam pressure is suitable for the operation of COIL, which produces a good condition for the steady operation of laser system and an excellent laser output.

  9. Review of explosive-driven iodine lasers in the U.S.

    NASA Astrophysics Data System (ADS)

    Jones, Randy C.

    1995-03-01

    High-explosive charges were used in the early 1980's at Los Alamos National Laboratory to pump high-energy atomic-iodine lasers. Laser outputs at the kilojoule level were measured in a series of experiments. Two techniques were used to convert the high-explosive (HE) energy release to optical radiation for the photolysis of the perfluoroalkyliodide fuel. One technique used strong shockwaves propagating through argon gas and driven by the detonation as an intense optical pump source. The second approach used exploding metal films driven by megampere-level current pulses from explosive-driven magnetic flux compression generators. The optical extraction system for both types of single-pulse lasers was a power oscillator configuration using a stable resonator. The purpose of these experiments was to evaluate the scaling potential of HE-driven lasers for a number of applications including inertial confinement fusion. The HE field experiments were supported by a number of laboratory laser experiments. Exploding wires were used to pump 100-J atomic-iodine lasers (and 20-J molecular iodine lasers). Atomic-iodine lasers were also pumped with exploding metal films. In support of this work, several types of optical pump sources were characterized. These included HE-driven shockwaves in a variety of rare gases, exploding metal wires and films, surface discharges, ablating-wall flashlamps, and xenon flashlamps. Equivalent blackbody temperatures as a function of various parameters were measured for each source using absolutely calibrated photodetectors equipped with optical bandpass filters.

  10. A 10-watt CW photodissociation laser with IODO perfluoro-tert-butane

    NASA Technical Reports Server (NTRS)

    Tabibi, Bagher; Venable, Demetrius D.

    1989-01-01

    NASA has been investigating the feasibility of direct solar-pumped laser systems for power beaming in space. Among the various gas, liquid, and solid laser systems being proposed as candidates for solar-pumped lasers, the iodine photodissociation gas laser has demonstrated its potential for space application. Of immediate attention is the determination of system requirements and the choice of lasants to improve the system efficiency. The development of an efficient iodine laser depends on the availability of a suitable iodide which has favorable laser kinetics, chemically reversibility, and solar energy utilization. Among the various alkyliodide lasants comparatively tested in a long-pulse system, perfluoro- tert-butyl iodide, T-C4F9I, was found to be the best. However, the operating conditions for the laser medium in a continuously pumped and continuous-flow iodine laser differ considerably from those in the pulsed regime. The results of the continuous wave (CW)) laser performance from t-C4F9I are reported. Perfluoro- n-propyl iodide, n-C3F7I is used for comparison because of its universal use in photodissociation iodine lasers.

  11. Determination of iodine in oyster tissue by isotope dilution laser resonance ionization mass spectrometry

    SciTech Connect

    Fassett, J.D.; Murphy, T.J. )

    1990-02-15

    The technique of laser resonance ionization mass spectrometry has been combined with isotope dilution analysis to determine iodine in oyster tissue. The long-lived radioisotope, 129I, was used to spike the samples. Samples were equilibrated with the 129I, wet ashed under controlled conditions, and iodine separated by coprecipitation with silver chloride. The analyte was dried as silver ammonium iodide upon a tantalum filament from which iodine was thermally desorbed in the resonance ionization mass spectrometry instrument. A single-color, two-photon resonant plus one-photon ionization scheme was used to form positive iodine ions. Long-lived iodine signals were achieved from 100 ng of iodine. The precision of 127I/129I measurement has been evaluated by replicate determinations of the spike, the spike calibration samples, and the oyster tissue samples and was 1.0%. Measurement precision among samples was 1.9% for the spike calibration and 1.4% for the oyster tissue. The concentration of iodine determined in SRM 1566a, Oyster Tissue, was 4.44 micrograms/g with an estimate of the overall uncertainty for the analysis of +/- 0.12 microgram/g.

  12. LASERS: Efficient chemical oxygen — iodine laser with a high total pressure of the active medium

    NASA Astrophysics Data System (ADS)

    Zagidullin, M. V.; Nikolaev, V. D.; Svistun, M. I.; Khvatov, N. A.; Heiger, G. D.; Madden, T. J.

    2001-01-01

    A new concept of obtaining a high total pressure of the active medium of a chemical oxygen — iodine laser (OIL) is proposed and verified. The nozzle unit of the laser consists of the alternating vertical arrays of cylindrical nozzles to produce high-pressure nitrogen jets, plane slotted nozzles for the flow of O2(1Δ) oxygen, and vertical arrays of cylindrical nozzles to inject the N2 — I2 mixture between the first two streams. For a molar chlorine flow rate of 39.2 mmol s-1, the output power was 700 W and the chemical efficiency was 19.7 %. The combined use of the ejector nozzle unit proposed to obtain the active medium and a super-sonic diffuser allows a significant simplification of the ejection system for the exhaust active medium of the OIL.

  13. Planar temperature measurement in compressible flows using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Hollo, Steven D.; Mcdaniel, James C.

    1991-01-01

    A laser-induced iodine fluorescence technique that is suitable for the planar measurement of temperature in cold nonreacting compressible air flows is investigated analytically and demonstrated in a known flow field. The technique is based on the temperature dependence of the broadband fluorescence from iodine excited by the 514-nm line of an argon-ion laser. Temperatures ranging from 165 to 245 K were measured in the calibration flow field. This technique makes complete, spatially resolved surveys of temperature practical in highly three-dimensional, low-temperature compressible flows.

  14. Numerical study of He/CF{sub 3}I pulsed discharge used to produce iodine atom in chemical oxygen-iodine laser

    SciTech Connect

    Zhang Jiao; Wang Yanhui; Wang Dezhen; Duo Liping; Li Guofu

    2013-04-15

    The pulsed discharge for producing iodine atoms from the alkyl and perfluoroalky iodides (CH{sub 3}I, CF{sub 3}I, etc.) is the most efficient method for achieving the pulse operating mode of a chemical oxygen-iodine laser. In this paper, a one-dimensional fluid model is developed to study the characteristics of pulsed discharge in CF{sub 3}I-He mixture. By solving continuity equation, momentum equation, Poisson equation, Boltzmann equation, and an electric circuit equation, the temporal evolution of discharge current density and various discharge products, especially the atomic iodine, are investigated. The dependence of iodine atom density on discharge parameters is also studied. The results show that iodine atom density increases with the pulsed width and pulsed voltage amplitude. The mixture ratio of CF{sub 3}I and helium plays a more significant role in iodine atom production. For a constant voltage amplitude, there exists an optimal mixture ratio under which the maximum iodine atom concentration is achieved. The bigger the applied voltage amplitude is, the higher partial pressure of CF{sub 3}I is needed to obtain the maximum iodine atom concentration.

  15. Active medium gain study of electric-discharge oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Kolobyanin, Yuriy; Adamenkov, Yuriy; Vyskubenko, Boris; Goryachev, Leonid; Ilyin, Sergey; Kalashnik, Anatoliy; Rakhimova, Tatiana; Rogozhnikov, Georgiy

    2007-05-01

    The paper reports on experimental studies of the active medium gain in supersonic electric-discharge oxygen-iodine laser (DOIL) based on traveling mw discharge. The measurements have included: absolute concentration, yield, and energy efficiency of production of SO in pure oxygen and oxygen-helium mixes at an oxygen partial pressure 3 to 15 Torr. For the gas flow to get rid of atomic oxygen, both heterogeneous mercury oxide coatings of the tube walls and homogeneous additives to the work mix, such as nitrogen oxide, have been used. The active medium of DOIL was formed using a nozzle array of the type of ejector sized as 10*50 mm2. The singlet oxygen-helium mix was supplied through three rows of sonic cylindrical nozzles, while the iodine-carrier gas mix - through two rows of supersonic conical nozzles with a half-opening angle of 10°(arc). The gas-phase iodine was produced in a quartz cell filled with iodine crystals. Room-temperature iodine vapors were picked up with a carrier gas (nitrogen or helium) and thus delivered into the nozzle array. The active medium was investigated by the high-resolution laser diode spectroscopy approach that used the laser type Vortex 6025 purchased from New Focus, Inc. The laser medium gain factor was determined by the intra-cavity approach having a sensitivity about 1*10 -6 cm -1. The static temperature of the medium was determined from the measurements of gain half-width. The gain of the active medium of electric-discharge OIL has been investigated. The DOIL in use was operating on a mix composed as O II:He=1:1 at a total pressure of 6 Torr and flowrate - about 1 mmol/s. With helium as an iodine carrier gas at a flowrate ~3 mmol/s, we have recorded a positive gain in the DOIL medium.

  16. Generation of 14 GHz radiation using a two frequency iodine laser

    NASA Astrophysics Data System (ADS)

    Nicholson, J. W.; Rudolph, W.; Hager, G.

    1998-06-01

    A mode-locked and gain-switched photolytic iodine laser Zeeman tuned to operate simultaneously on the two strongest hyperfine transitions is shown to emit 1.315 μm radiation modulated at 13.9 GHz. The interaction of this laser radiation with suitable targets leads to the generation of microwave pulses that consist of only a few cycles at 13.9 GHz, making the system attractive for ultra-wide-band, short pulse radar applications.

  17. Test bench for studying the outlook for industrial applications of an oxygen-iodine laser

    SciTech Connect

    Adamenkov, A A; Bakshin, V V; Bogachev, A V; Buryak, E V; Vdovkin, L A; Velikanov, S D; Vyskubenko, B A; Garanin, Sergey G; Gorbacheva, E V; Grigorovich, Sergei V; Il'in, S P; Il'kaev, R I; Ilyushin, Yurii N; Kalashnik, A M; Kolobyanin, Yu V; Leonov, M L; Svischev, V V; Troshkin, M V

    2007-07-31

    We report the development and tests of a chemical oxygen-iodine laser test bench based on a twisted-aerosol-flow singlet-oxygen generator and a supersonic laser model for studying the outlook for industrial applications of this laser. The maximal output power of the laser is {approx}65 kW (the average power is {approx}50 kW), corresponding to a specific output power of {approx}110 W cm{sup -2}. The maximal chemical efficiency is {approx}34%. (letters)

  18. Repetitively pulsed, 70-J photolytic iodine laser with excellent optical and long-reliable operation

    NASA Astrophysics Data System (ADS)

    Schlie, L. A.; Rathge, R. D.

    1995-06-01

    The performance of a repetitively pulsed, 70 joule, closed cycle 1.3 mu M photolytic atomic iodine laser with excellent beam quality (BQ = 1.15) is presented. This BQ was exhibited in the fundamental mode from a M = 3.1 confocal unstable resonator at a 0.5 Hz repetition rate. A closed cycle scrubber/laser fuel system consisting of a condensative-evaporative section, two Cu wool I2 reactor regions, and an internal turbo-blower enabled the laser to operate very reliably with low maintenance. The fuel system provided C3F7I gas at 10-60 torr absent of the photolytic quenching by-product I2. Using a turbo-molecular blower longitudinal flow velocities greater than 10 m/s were achieved through the 150 cm long by 7.5 x 7.5 cm(exp 2) cross sectional photolytic iodine gain region. In addition to the high laser output and excellent BQ, the resulting 8-12 mu s laser pulse had a coherence length greater than 45 meters and polarization extinction ratio better than 100:1. Projections from this pulsed photolytic atomic iodine laser technology to larger energies, higher repetition rates, and variable pulse widths are discussed.

  19. Optical pumping of the oxygen-iodine laser medium

    NASA Astrophysics Data System (ADS)

    Zagidullin, Marsel V.; Malyshev, Mikhail S.; Azyazov, Valeriy N.; Heaven, Michael C.

    2016-03-01

    The kinetics of the processes in an O2/I2/Ar/H2O gas flow that is irradiated simultaneously by light at wavelengths near 500 nm and 1315 nm, is considered. Radiation at 500 nm is used to photodissociate about 1% of the iodine molecules. The radiation at 1315 nm excites atomic iodine to the 2P1/2 state. Singlet oxygen molecules are produced via the energy exchange process I(2P1/2)+O2(X3Σ) → I(2P3/2) + O2(a1Δ), while I(2P1/2)+O2(a1Δ) energy pooling produces b1Σ oxygen. I(2P1/2) and O2(b1Σ) then accelerate the dissociation of I2. This active medium may reach ~40 W/cm-2 at an optical efficiency of 50%.

  20. Velocity Field Measurements in Rarefied, Hypersonic Flows of Nitrogen Using Laser-Induced Fluorescence of Iodine

    NASA Astrophysics Data System (ADS)

    Cecil, Eric

    Velocity fields are measured in the shock layer and boundary layer on a plate with a cylindrical fin immersed in a hypersonic, free jet of nitrogen, using laser-induced fluorescence (LIF) of iodine. A sheet beam from a single-mode argon laser at 514 nm is used to excite hyperfine components of the P(13), R(15) and P(48), P(103) blended rotational-vibrational lines in the B-X electronic transition for iodine seeded in the flow. The Doppler broadening and shift of these lines, and the relative rotational line strengths are determined for excitation spectra recorded in a planar grid. Using this measurement technique, estimates for iodine of the mass velocity component and kinetic temperature of translation in the direction of laser propagation, rotational temperature, and relative number density are determined at each point. Sectional planes of the flow over the body are investigated at a spatial resolution on the scale of the molecular mean-free-path in the free jet near the plate leading edge. Two directions within each plane are examined, to determine the velocity vector and to investigate translational non-equilibrium. Predictions from two direct simulation Monte Carlo computations of the flow are compared with the measurements. Large values of slip velocity and temperature jump at the plate surface are observed for iodine. Measurements and DSMC predictions indicate strong translational non-equilibrium effects for the iodine in the shock wave and the thick boundary layer on the plate, and are qualitatively consistent with a bimodal velocity distribution function. As a consequence of the ratio of molecular masses, the translational non-equilibrium of iodine is much greater than for nitrogen.

  1. Application of a telescopic resonator to high-power chemical oxygen-iodine lasers

    SciTech Connect

    Yoshida, Sanichiro; Shimizu, Kouki; Tahil, Hari; Tanaka, Ikuzo . Laser Lab.)

    1994-01-01

    The application of an intraresonator telescope to high-power chemical oxygen-iodine lasers to decrease the output beam divergence is analyzed and demonstrated. A theoretical formula based on the ABCD matrix theory is developed to analyze the characteristics of the telescopic resonator. Calculations are carried out using Galilean type telescopes with magnification factors in the range of two to four, and the high-power chemical oxygen-iodine laser as an analysis model. By locating the telescope at a proper position on the optical axis, the overall telescopic resonator can be conveniently tailored to the hardware of this model laser in a way that the beam divergence and the resonator stability can be improved simultaneously. Experiments are carried out for one of the conditions used in the calculations. Measured divergence angles are in excellent agreement with the theoretical values.

  2. Oxygen-iodine ejector laser with a centrifugal bubbling singlet-oxygen generator

    SciTech Connect

    Zagidullin, M V; Nikolaev, V D; Svistun, M I; Khvatov, N A

    2005-10-31

    It is shown that if a supersonic oxygen-iodine ejector laser is fed by singlet oxygen from a centrifugal bubbling generator operating at a centrifugal acceleration of {approx}400g, the laser output power achieves a value 1264 W at a chemical efficiency of 24.6% for an alkaline hydrogen peroxide flow rate of 208 cm{sup 3}s{sup -1} and a specific chlorine load of 1.34 mmol s{sup -1} per square centimetre of the bubble layer. (lasers)

  3. Similarity criteria in calculations of the energy characteristics of a cw oxygen - iodine laser

    SciTech Connect

    Mezhenin, A V; Azyazov, V N

    2012-12-31

    The calculated and experimental data on the energy efficiency of a cw oxygen - iodine laser (OIL) are analysed based on two similarity criteria, namely, on the ratio of the residence time of the gas mixture in the resonator to the characteristic time of extraction of the energy stored in singlet oxygen td and on the gain-to-loss ratio {Pi}. It is shown that the simplified two-level laser model satisfactorily predicts the output characteristics of OILs with a stable resonator at {tau}{sub d} {<=} 7. Efficient energy extraction from the OIL active medium is achieved in the case of {tau}{sub d} = 5 - 7, {Pi} = 4 - 8. (lasers)

  4. Conversion of the 'Iskra-5' iodine laser to second-harmonic operating mode

    SciTech Connect

    Annenkov, V I; Vinogradskiy, L M; Gaidash, V A; Galakhov, I V; Garanin, Sergey G; Zhidkov, N V; Zubkov, A V; Kalipanov, S V; Kargin, V A; Kirillov, G A; Kovalenko, V P; Kochemasov, G G; Kravchenko, A G; Krotov, V A; Lazarchuk, V P; Lapin, S G; Bespalov, V I; Bredikhin, V I; Ershov, V P; Zil'berberg, V V

    2005-11-30

    The conversion of the 'Iskra-5' iodine laser to the regime of fusion target irradiation by second harmonic radiation at 657.5 nm is reported. The laser upgrading enabled obtaining from 12 channels a total second-harmonic energy yield of 2.5 kJ, which corresponds to an output power of 5 TW. The conversion efficiency was equal to {approx}50% in experiments with DKDP crystals with an aperture of 35 cm. A series of 12-channel experiments was conducted involving second-harmonic irradiation of microtargets. (lasers)

  5. Improvement in Suppression of Pulsed Nd:YAG Laser Light With Iodine Absorption Cells for Filtered Rayleigh Scattering Measurements

    NASA Technical Reports Server (NTRS)

    Seasholtz, Richard G.; Buggele, Alvin E

    1997-01-01

    Filtered Rayleigh scattering using iodine absorption cells is an effective technique for obtaining density, temperature, and velocity measurements in high speed confined flows. By tuning a single frequency laser to a strong iodine absorption line, stray scattered laser light can be greatly suppressed. For example, the minimum transmission predicted by an iodine absorption model calculation is less than 10(exp -5) at the 18788.44/cm line using a 200 mm absorption cell containing iodine vapor at 0.46 T. Measurements obtained by other researches using a CW Nd:YAG laser agree with the model calculations. However, measurements made by us and by others using Q-switched, injection-seeded, frequency doubled Nd:YAG lasers only show minimum transmission of about 3 x 10(exp -3). This greatly reduces the applicability of the filtered Rayleigh scattering technique using these lasers in experiments having large amounts of stray scattered laser light. The purposes of the present study are to characterize the spectrum of the excess light transmitted by the iodine cell and to make changes to the laser to reduce the transmitted laser light. Transmission data as a function of laser frequency for the iodine absorption line at 18788.44/cm are presented. A planar mirror Fabry-Perot interferometer was used to characterize the frequency spectrum of the light passed through the cell. Measurements taken with the laser tuned to the center of the iodine absorption line show the light transmitted through the iodine cell to have a component with a bandwidth of about 40 GHz. This is probably caused by other modes in the laser that exist in spite of the single frequency injection beam. A second broadband component was also observed, possibly caused by the laser flash lamps or by fluorescence. An intracavity etalon was installed in the laser oscillator cavity to suppress the 40 GHz component. Measurements taken with the etalon tuned to the injection frequency showed a reduction in the transmitted

  6. Use of basic deuterium peroxide in the chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Vetrovec, John; Yang, Tientsai T.; Copeland, Drew A.

    2000-05-01

    The chemical oxygen-iodine laser (COIL) uses a reaction of gaseous chorine and aqueous solution of basic oxygen peroxide (BHP) to produce oxygen singlet delta molecules, O2(1(Delta) ). Quenching of O2(1(Delta) ) during its extraction from the BHP solution and quenching of excited atomic iodine I* by water vapor from the O2(1(Delta) ) production process are well-known parasitic effects in COIL. This paper shows that both of these effects can be significantly reduced by replacing the hydrogen 1H1 isotope atoms in BHP by the 1H2 isotope atoms. In addition to restoring laser power lost to parasitic quenching, use of basic deuterium peroxide (BDP) rather than BHP is expected to allow generation of O2(1(Delta) ) at elevated temperature. This approach promises to save refrigerant, reduce the risk of BDP freezing, and delay precipitation of salt form BDP solution. Methods for producing BDP are outlined.

  7. Nuclear-driven flashlamp pumping of the atomic iodine laser. Final report

    SciTech Connect

    Miley, G.H.

    1992-03-01

    This report is a study of the atomic iodine laser pumped with nuclear- excited XeBr fluorescence. Preliminary experiments, conducted in the TRIGA reactor investigated the fluorescence of the excimer XeBr under nuclear pumping with {sup 10}B and {sup 3}He, for use as a flashlamp gas to stimulate the laser. These measurements included a determination of the fluorescence efficiency (light emitted in the wavelength region of interest, divided by energy deposited in the gas) of XeBr under nuclear pumping, with varying excimer mixtures. Maximum fluorescence efficiencies were approximately 1%. In order to better understand XeBr under nuclear excitation, a kinetics model of the system was prepared. The model generated the time-dependant concentrations of 20 reaction species for three pulse sizes, a TRIGA pulse, a fast burst reactor pulse, and an e-beam pulse. The modeling results predicted fluorescence efficiencies significantly higher (peak efficiencies of approximately 10%) than recorded in the fluorescence experiments. The cause of this discrepancy was not fully determined. A ray tracing computer model was also prepared to evaluate the efficiency with which nuclear-induced fluorescence generated in one cavity of a laser could be coupled into another cavity containing an iodine lasant. Finally, an experimental laser cell was constructed to verify that nuclear-induced XeBr fluorescence could be used to stimulate a laser. Lasing was achieved at 1.31 micron in the TRIGA using C{sub 3}F{sub 7}I, a common iodine lasant. Peak laser powers were approximately 20 mW. Measured flashlamp pump powers at threshold agreed well with literature values, as did lasant pressure dependency on laser operation.

  8. Intracavity second harmonic generation of chemical oxygen iodine laser with a Brewster cut LBO crystal

    NASA Astrophysics Data System (ADS)

    Shimizu, Tomohiro; Tezuka, Takeo; Chen, Kuntetsu; Hashimoto, Katsuki; Uchiyama, Taro

    1997-04-01

    Second harmonic generation of chemical oxygen iodine laser was investigated with a Brewster cut LBO crystal. By utilizing a Brewster cut LBO crystal the loss in the resonator can be suppressed. Further, by reducing crystal absorption, the crystal can't be heated and go off phase match or even crack due to thermal stress. We could obtain 16.4 W of second harmonic power and keep out the crystal from being destroyed by the damage of thermal stress.

  9. REVIEW: Excited states in the active media of oxygen — iodine lasers

    NASA Astrophysics Data System (ADS)

    Azyazov, V. N.

    2009-11-01

    A review of investigations of kinetic processes in active media oxygen — iodine lasers (OILs) performed in the last decade is presented. The mechanisms of pumping and quenching of electronically and vibrationally excited O2 and I2 molecules are considered, and dissociation mechanisms of I2 in the active medium of the OIL are analysed. The values of kinetic constants of processes proceeding in the active media of OILs are recommended.

  10. Pulsed oxygen-iodine chemical laser initiated by an electrical discharge

    SciTech Connect

    Zhang Rongyao; Chen Fang; Song Xueqin; Xu Qingzhou; Huan Changqing; Zhuang Qi; Zhang Cunhao

    1988-08-01

    This paper demonstrates for the first time the feasibility of an electrically initiated, pulsed oxygen-iodine laser which can be initiated efficiently by low energy electrons. By electrical initiation, an O/sub 2/(/sup 1/..delta..)--CH/sub 3/I--N/sub 2/ mixture has been made to lase with an output energy of 130 mJ. The efficiency of the electrical initiation is 350 times higher than that obtained with photo-initiation.

  11. Similarity criteria in calculations of the energy characteristics of a cw oxygen - iodine laser

    NASA Astrophysics Data System (ADS)

    Mezhenin, A. V.; Azyazov, V. N.

    2012-12-01

    The calculated and experimental data on the energy efficiency of a cw oxygen - iodine laser (OIL) are analysed based on two similarity criteria, namely, on the ratio of the residence time of the gas mixture in the resonator to the characteristic time of extraction of the energy stored in singlet oxygen td and on the gain-to-loss ratio Π. It is shown that the simplified two-level laser model satisfactorily predicts the output characteristics of OILs with a stable resonator at τd <= 7. Efficient energy extraction from the OIL active medium is achieved in the case of τd = 5 - 7, Π = 4 - 8.

  12. Efficient generation in a chemical oxygen - iodine laser with a low buffer-gas flow rate

    SciTech Connect

    Azyazov, V N; Safonov, V S; Ufimtsev, N I

    2002-09-30

    The efficient generation in a chemical oxygen - iodine laser (COIL) with a low buffer-gas flow rate for Mach numbers M {<=} 1 is demonstrated. The maximum output power of the COIL was 415 W for a molecular chlorine flow rate of 20 mmol s{sup -1}, which corresponds to a chemical efficiency {eta}{sub ch} =23%. It is shown that the substitution of the buffer gas CO{sub 2} for N{sub 2} does not cause any significant variation in the dependence of the output power on the degree of dilution of the active medium. (lasers)

  13. Advanced technologies in chemical oxygen-iodine lasers for industrial applications

    NASA Astrophysics Data System (ADS)

    Endo, Masamori; Nagatomo, Syoji; Takeda, Shuzaburo; Wani, Fumio; Nanri, Kenzo; Fujioka, Tomoo

    1998-05-01

    A new concept of energy network system, `optical power system', was proposed. In this system, optical power is generated at a laser facility and it is distributed to users through optical fiber such as electric power system. The authors have started a feasibility study of this concept based on the latest chemical oxygen-iodine laser technology. 23.4% of chemical efficiency was obtained using nitrogen as buffer gas. Buffer gas cooling remarkably increased chemical efficiency. Liquid-jet type singlet oxygen generator (SOG) and twisted aerosol SOG (TA-SOG) were compared with the same setup. TA-SOG showed good performance especially in the high gas flow velocity range.

  14. COIL--Chemical Oxygen Iodine Laser: advances in development and applications

    NASA Astrophysics Data System (ADS)

    Kodymova, Jarmila

    2005-09-01

    Advantageous features of Chemical Oxygen-Iodine Laser (COIL) for laser technologies have increased considerably activities of international COIL communities during past ten years. They have been focused on the advanced concepts of hardware designs of the COIL subsystems, and testing and scaling-up of existing laser facilities. Prospective special applications of COIL technology, both civil and military, have received a significant attention and gained concrete aims. The paper is introduced by a brief description of the COIL operation mechanism and key device subsystems. It deals then with presentation of some investigated advanced concepts of singlet oxygen generators, alternative methods for atomic iodine generation, a mixing and ejector nozzle design to downsize a pressure recovery system, and optical resonators for high power COIL systems. The advanced diagnostics and computational modeling are also mentioned as very useful tools for critical insight into the laser kinetics and fluid dynamics, supporting thus the COIL research. The recent progress in the COIL development moves this laser closer to the application projects that are also briefly presented.

  15. Molecular iodine fluorescence spectra generated with helium-neon lasers for spectrometer calibration.

    PubMed

    Williamson, J Charles

    2010-12-01

    Gas-phase molecular iodine laser-induced fluorescence (LIF) spectra were recorded out to 815 nm at 1 cm(-1) resolution using green, yellow, and red helium-neon (HeNe) lasers as excitation sources. Nine previously unreported I(2) B←X absorption transitions accessed by these lasers were identified, and specific rovibronic transition assignments were made for two hundred LIF peaks--more than sixty per laser. These I(2) LIF peaks can be used to calibrate the vacuum wavenumber coordinate of spectrometers to better than 0.1 cm(-1) accuracy. In particular, green HeNe excitation of the I(2) R(106) 28-0 transition leads to strong fluorescence well suited for calibration, with a rotational doublet spacing of 15 cm(-1) and a doublet-to-doublet spacing of 190 cm(-1). Calibration by HeNe I(2) LIF may be an especially valuable technique for Raman spectroscopy applications. PMID:21144161

  16. A unified planar measurement technique for compressible flows using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Hollo, Steven D.; Mcdaniel, James C.

    1992-01-01

    A unified laser-induced fluorescence technique for conducting planar measurements of temperature, pressure and velocity in nonreacting, highly compressible flows has been developed, validated and demonstrated. Planar fluorescence from iodine, seeded into air, was induced by an argon-ion laser and collected using a liquid-nitrogen cooled CCD camera. In the measurement technique, temperature is determined from the fluorescence induced with the laser operated broad band. Pressure and velocity are determined from the shape and position of the fluorescence excitation spectrum which is measured with the laser operated narrow band. The measurement approach described herein provides a means of obtaining accurate, spatially-complete maps of the primary flow field parameters in a wide variety of cold supersonic and transonic flows.

  17. Test bed for a high throughput supersonic chemical oxygen - iodine laser

    SciTech Connect

    Singhal, Gaurav; Mainuddin; Rajesh, R; Varshney, A K; Dohare, R K; Kumar, Sanjeev; Singh, V K; Kumar, Ashwani; Verma, Avinash C; Arora, B S; Chaturvedi, M K; Tyagi, R K; Dawar, A L

    2011-05-31

    The paper reports the development of a test bed for a chemical oxygen - iodine laser based on a high throughput jet flow singlet oxygen generator (JSOG). The system provides vertical singlet oxygen extraction followed by horizontal orientation of subsequent subsystems. This design enables the study of flow complexities and engineering aspects of a distributed weight system as an input for mobile and other platform-mounted systems developed for large scale power levels. The system under consideration is modular and consists of twin SOGs, plenum and supersonic nozzle modules, with the active medium produced in the laser cavity. The maximal chlorine flow rate for the laser is {approx}1.5 mole s{sup -1} achieving a typical chemical efficiency of about 18%. (lasers)

  18. Analysis of the effect of anhydride of trifluoroacetanhydride in the working mixture composition on the operation of iodine photodissociation laser

    NASA Astrophysics Data System (ADS)

    Vinogradskii, L. M.; Polozov, A. A.; Khudikov, N. M.

    2015-12-01

    The effect of the (CF3CO)2O (trifluoroacetanhydride) buffer additive on the operation of an iodine photodissociation laser is studied experimentally. Comparative experiments for determining the laser energy of the iodine laser with the replacement of the working substance with this buffer additive and without it and with widely used buffer gas SF6 (sulfur hexafluoride) are carried out. Optical inhomogeneities in the working volume, emerging during pumping of working mixtures based on i-C3F7I (perfluoroalkyl iodide) with buffer additives (CF3CO)2O and C6F14 (perfluorohexane), are measured. The results of experiments are analyzed.

  19. Comparing the efficiency of supersonic oxygen-iodine laser with different mixing designs

    NASA Astrophysics Data System (ADS)

    Vyskubenko, Boris A.; Adamenkov, A. A.; Bakshin, V. V.; Efremov, V. I.; Ilyin, S. P.; Kolobyanin, Yu. V.; Krukovsky, I. M.; Kudryashov, E. A.; Moiseyev, V. B.

    2003-11-01

    The paper presents experimental studies of supersonic oxygen-iodine laser (OIL) using twisted-flow singlet oxygen generator (SOG) over a wide range of the singlet oxygen pressures and the buffer gas flow rates. The experiments used different designs of the nozzle unit and mixing system for singlet oxygen and iodine gas with the carrier gas (such as nitrogen or helium). For a wide range of the key parameters, the study looked at the efficiency of supersonic OIL with variation of the singlet oxygen pressure. The measurements were made for different positions of the iodine injection plane with respect to the critical cross-section (both in the subsonic part of the nozzle and in the supersonic flow). The gas pressure at the nozzle unit entry was varied from 50 to 250 Torr. The total pressure loss have been found for different mixing designs. Experimental curves are given for energy performance and chemical efficiency of the supersonic OIL as a function of the key parameters. Comparison is made between the calculated and experimental data. For the optimum conditions of OIL operation, chemical efficiency of 25-30% has been achieved.

  20. Quantitative characterization of a nonreacting, supersonic combustor flowfield using unified, laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Fletcher, D. G.; Mcdaniel, J. C.

    1989-01-01

    A calibrated, nonintrusive optical technique, laser-induced iodine fluorescence (LIIF) was used to quantify the steady, compressible flowfield of a nonreacting, supersonic combustor. The combustor was configured with single and staged, transverse-air injection into a supersonic-air freestream behind a rearward-facing step. Pressure, temperature, two-velocity components, and injectant mole fraction were measured with high spatial resolution in the three-dimensional flowfields. These experimental results provide a benchmark set of data for validation of computational fluid dynamic (CFD) codes being developed to model supersonic combustor flowfields.

  1. Mode locking of a CW supersonic chemical oxygen-iodine laser

    SciTech Connect

    Phipps, S.P.; Helms, C.A.; Copland, R.J.; Rudolph, W.; Truesdell, K.A.; Hager, G.D.

    1996-12-01

    This paper presents the results of the first mode-locking experiments on a supersonic chemical oxygen-iodine laser (COIL). Mode locking has been achieved using an acoustooptic modulator (AOM) and lasing demonstrated on the TEM{sub 00} modes with a small intracavity aperture. A dc magnetic field was used to increase the number of axial modes and a peak power of 2.5 kW has been reached with a pulse width of 2.1 ns at a repetition rate of 43.68 MHz.

  2. Chemical oxygen-iodine laser (COIL) for the dismantlement of nuclear facilities

    NASA Astrophysics Data System (ADS)

    Hallada, Marc R.; Seiffert, Stephan L.; Walter, Robert F.; Vetrovec, John

    2000-05-01

    The dismantlement of obsolete nuclear facilities is a major challenge for both the US Department of Energy and nuclear power utilities. Recent demonstrations have shown that lasers can be highly effective for size reduction cutting, especially for the efficient storage and recycling of materials. However, the full benefits of lasers can only be realized with high average power beams that can be conveniently delivered, via fiber optics, to remote and/or confined areas. Industrial lasers that can meet these requirements are not available now or for the foreseeable future. However, a military weapon laser, a Chemical Oxygen Iodine Laser (COIL), which has been demonstrated at over a hundred kilo Watts, could be adapted to meet these needs and enable entirely new industrial applications. An 'industrialized' COIL would enable rapid sectioning of thick and complex structures, such as glove boxes, reactor vessels, and steam generators, accelerating dismantlement schedules and reducing worker hazards. The full advantages of lasers in dismantlement could finally be realized with a portable COIL which is integrated with sophisticated robotics. It could be built and deployed in less than two years, breaking the paradigm of labor-intensive dismantlement operations and cutting processing times and costs dramatically.

  3. Combining laser frequency combs and iodine cell calibration techniques for Doppler detection of exoplanets

    NASA Astrophysics Data System (ADS)

    Cahoy, Kerri; Fischer, Debra; Spronck, Julien; DeMille, David

    2010-07-01

    Exoplanets can be detected from a time series of stellar spectra by looking for small, periodic shifts in the absorption features that are consistent with Doppler shifts caused by the presence of an exoplanet, or multiple exoplanets, in the system. While hundreds of large exoplanets have already been discovered with the Doppler technique (also called radial velocity), our goal is to improve the measurement precision so that many Earth-like planets can be detected. The smaller mass and longer period of true Earth analogues require the ability to detect a reflex velocity of ~10 cm/s over long time periods. Currently, typical astronomical spectrographs calibrate using either Iodine absorptive cells or Thorium Argon lamps and achieve ~10 m/s precision, with the most stable spectrographs pushing down to ~2 m/s. High velocity precision is currently achieved at HARPS by controlling the thermal and pressure environment of the spectrograph. These environmental controls increase the cost of the spectrograph, and it is not feasible to simply retrofit existing spectrometers. We propose a fiber-fed high precision spectrograph design that combines the existing ~5000-6000 A Iodine calibration system with a high-precision Laser Frequency Comb (LFC) system from ~6000-7000 A that just meets the redward side of the Iodine lines. The scientific motivation for such a system includes: a 1000 A span in the red is currently achievable with LFC systems, combining the two calibration methods increases the wavelength range by a factor of two, and moving redward decreases the "noise" from starspots. The proposed LFC system design employs a fiber laser, tunable serial Fabry-Perot cavity filters to match the resolution of the LFC system to that of standard astronomical spectrographs, and terminal ultrasonic vibration of the multimode fiber for a stable point spread function.

  4. Singlet oxygen generator for a solar powered chemically pumped iodine laser

    NASA Technical Reports Server (NTRS)

    Busch, G. E.

    1984-01-01

    The potential of solid phase endoperoxides as a means to produce single-delta oxygen in the gas phase in concentrations useful to chemical oxygen-iodine lasers was investigated. The 1,4 - endoperoxide of ethyl 3- (4-methyl - 1-naphthyl) propanoate was deposited over an indium-oxide layer on a glass plate. Single-delta oxygen was released from the endoperoxide upon heating the organic film by means of an electrical discharge through the conductive indium oxide coating. The evolution of singlet-delta oxygen was determined by measuring the dimol emission signal at 634 nm. Comparison of the measured signal with an analytic model leads to two main conclusions: virtually all the oxygen being evolved is in the singlet-delta state and in the gas phase, and there is no significant quenching other than energy pooling on the time scale of the experiment (approximately 10 msec). The use of solid phase endoperoxide as a singlet-delta oxygen generator for an oxygen-iodine laser appears promising.

  5. Mechanism of singlet oxygen deactivation in an electric discharge oxygen – iodine laser

    SciTech Connect

    Azyazov, V N; Mikheyev, P A; Torbin, A P; Pershin, A A; Heaven, M C

    2014-12-31

    We have determined the influence of the reaction of molecular singlet oxygen with a vibrationally excited ozone molecule O{sub 2}(a {sup 1}Δ) + O{sub 3}(ν) → 2O{sub 2} + O on the removal rate of O{sub 2}(a {sup 1}Δ) in an electric-discharge-driven oxygen – iodine laser. This reaction has been shown to be a major channel of O{sub 2}(a {sup 1}Δ) loss at the output of an electric-discharge singlet oxygen generator. In addition, it can also contribute significantly to the loss of O{sub 2}(a {sup 1}Δ) in the discharge region of the generator. (lasers)

  6. Optical frequency measurements with the global positioning system: tests with an iodine-stabilized He-Ne laser.

    PubMed

    Fox, Richard W; Diddams, Scott A; Bartels, Albrecht; Hollberg, Leo

    2005-01-01

    Global positioning system- (GPS-) referenced optical frequency combs based on mode-locked lasers offer calibrations for length metrology traceable to international length standards through the SI second and the speed of light. The absolute frequency of an iodine-stabilized He-Ne laser [127I2 R(127) 11-5 f component] was measured with a femtosecond comb referenced to a multichannel GPS timing receiver. The expected performance and limitations of GPS-referenced comb measurements are discussed. PMID:15662892

  7. Mathematical modeling of a photovoltaic-laser energy converter for iodine laser radiation

    NASA Technical Reports Server (NTRS)

    Walker, Gilbert H.; Heinbockel, John H.

    1987-01-01

    Space-based laser power systems will require converters to change laser radiation into electricity. Vertical junction photovoltaic converters are promising devices for this use. A promising laser for the laser power station is the t-C4F9I laser which emits radiation at a wavelength of 1.315 microns. This paper describes the results of mathematical modeling of a photovoltaic-laser energy converter for use with this laser. The material for this photovoltaic converter is Ga(53)In(47)As which has a bandgap energy of 0.94 eV, slightly below the energy of the laser photons (0.943 eV). Results of a study optimizing the converter parameters are presented. Calculated efficiency for a 1000 vertical junction converter is 42.5 percent at a power density of 1 x 10 to the 3d power w/sq cm.

  8. Studies of oxygen-helium discharges for use in electric oxygen-iodine lasers

    NASA Astrophysics Data System (ADS)

    Zimmerman, Joseph William

    In recent work, the performance of the Electric Oxygen-Iodine Laser (ElectricOIL), developed in partnership by researchers at the University of Illinois and CU Aerospace, has been greatly improved through systematic study of various components of this new laser technology. One major contribution to the advancement of ElectricOIL technology has been the development of electric discharges capable of producing significant flow rates of the precursor electronically-excited molecular oxygen, O2(a1Delta). O2(a 1Delta) serves as an energy reservoir in the laser system, pumping atomic iodine by near-resonant energy transfer producing gain and laser on the I(2P1/2) → I(2P3/2 ) transition at 1315 nm. Initial experimental work with radio-frequency discharges showed the importance of controlling O-atom flow rates to reduce quenching losses of energy stored in O2(a1Delta), and determined proper selection of the helium diluent ratio and specific power deposition (power per O2 flow rate). Further experimental investigations with transverse capacitive radio-frequency discharges in O2/He/NO mixtures in the pressure range of 1-100 Torr and power range of 0.1-1.2 kW have indicated that O2(a1Delta) production is a strong function of geometry (transverse gap), excitation frequency, and pressure. These parameters along with gas flow mixture dictate the current density at which the discharge operates, and its modal characteristics (normal vs. abnormal, homogeneous vs. inhomogeneous). A key result is that to encourage efficient O2(a1Delta) production these parameters should be selected in order to promote a homogeneous (low current density) discharge. The discharge behavior is characterized using terminal current-voltage-characteristics, microwave interferometer measurements, and plasma emission intensity measurements. Numerous spectroscopic measurements of O2(a1Delta), oxygen atoms, and discharge excited states are made in order to describe the discharge performance dependent on

  9. A computational fluid dynamics simulation of a supersonic chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Waichman, K.; Rybalkin, V.; Katz, A.; Dahan, Z.; Barmashenko, B. D.; Rosenwaks, S.

    2007-05-01

    The dissociation of I II molecules at the optical axis of a supersonic chemical oxygen-iodine laser (COIL) was studied via detailed measurements and three dimensional computational fluid dynamics calculations. Comparing the measurements and the calculations enabled critical examination of previously proposed dissociation mechanisms and suggestion of a mechanism consistent with the experimental and theoretical results. The gain, I II dissociation fraction and temperature at the optical axis, calculated using Heidner's model (R.F. Heidner III et al., J. Phys. Chem. 87, 2348 (1983)), are much lower than those measured experimentally. Agreement with the experimental results was reached by using Heidner's model supplemented by Azyazov-Heaven's model (V.N. Azyazov and M.C. Heaven, AIAA J. 44, 1593 (2006)) where I II(A') and vibrationally excited O II(a1Δ) are significant dissociation intermediates.

  10. Experimental investigation of a supersonic swept ramp injector using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J.; Hollo, Steven D.; Mcdaniel, James C.

    1990-01-01

    Planar measurements of injectant mole fraction and temperature have been conducted in a nonreacting supersonic combustor configured with underexpanded injection in the base of a swept ramp. The temperature measurements were conducted with a Mach 2 test section inlet in streamwise planes perpendicular to the test section wall on which the ramp was mounted. Injection concentration measurements, conducted in cross flow planes with both Mach 2 and Mach 2.9 free stream conditions, dramatically illustrate the domination of the mixing process by streamwise vorticity generated by the ramp. These measurements, conducted using a nonintrusive optical technique (laser-induced iodine fluorescence), provide an accurate and extensive experimental data base for the validation of computation fluid dynamic codes for the calculation of highly three-dimensional supersonic combustor flow fields.

  11. Chemical oxygen-iodine laser with a cryosorption vacuum pump with different buffer gases

    NASA Astrophysics Data System (ADS)

    Xu, Mingxiu; Fang, Benjie; Sang, Fengting; Geng, Zicai; Li, Yongzhao; JIn, Yuqi

    2015-02-01

    A traditional pressure recovery system is the major obstacle to mobile chemical oxygen-iodine laser (COIL) for its huge volume. A cryosorption vacuum pump was used as the pressure recovery system for different buffer gases. It made COIL become a flexible, quiet and pressure-tight. Experiments were carried out on a verti- COIL, which was designed for N2 and energized by a square-pipe jet singlet oxygen generator (JSOG). The output power with CO2 was 27.3% lower than that with N2, but the zeolite bed showed an adsorption capacity threefold higher for CO2 than for N2 in the continuous operation. The great volume efficiency interested researchers.

  12. Quantitative determination of oxygen yield in a chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Kendrick, Kip R.; Helms, Charles A.; Quillen, Brian; Copland, R. J.

    1998-05-01

    With the advent of the Airborne Laser program, the emphasis of chemical oxygen-iodine laser (COIL) research has shifted toward improving the overall efficiency. A key component of COIL is the singlet-oxygen generator (SOG). To asses the efficiency of the SOG an accurate method of determining the yield of O2((alpha) 1(Delta) g),[O2((alpha) 1(Delta) g)]/[O2(total)] where [O2(total)]equals[O2((alpha) 1(Delta) g)]+[O2(X3(Sigma) g-)], has been developed. Absorption measurements of ground-state oxygen utilizing the magnetic-dipole transition, O2(X3(Sigma) g-) at 763 nm, have been obtained using a diode laser in conjunction with a multiple-pass Herriot-cell on a 10 kW class supersonic SOIL (RADICL). When RADICL is configured with a 0.35' throat, 15' diskpack, and a medium volume transition duct, with a diluent ratio (He:O2) of 3:1, the yield of O2((alpha) 1(Delta) g) in the diagnostic duct is 0.41 +/- 0.02.

  13. Tomographic imaging of a target directly irradiated in experiments on the Iskra-5 iodine laser facility

    SciTech Connect

    Bondarenko, S V; Garanin, R V; Garanin, Sergey G; Zhidkov, N V; Oreshkov, O V; Potapov, S V; Suslov, N A; Frolova, N V

    2010-12-29

    We set forth the data of experiments involving direct microtarget irradiation by the 12 second-harmonic beams ({lambda} = 0.66 {mu}m) of iodine laser radiation carried out on the Iskra-5 facility. For microtargets we employed glass shells {approx}500 {mu}m in diameter with {approx}1-{mu}m thick walls, which were filled with a DT mixture at a pressure p{sub DT} {approx} 3-4 atm. In one of these experiments, a tomographic image of the microtarget was recorded from the images obtained using pinhole cameras, which were arranged along seven different directions. The pinhole images were acquired in the X-ray radiation with photon energies above 1.5 keV. The procedure used for reconstructing the volume luminosity of the microtarget is described. An analysis of the tomographic image suggests that the compressed microtarget domain possesses a complex asymmetric shape; 20-30 {mu}m sized structural elements being clearly visible. The resultant data set allowed us to estimate the initial nonuniformity of microtarget surface irradiation by the laser radiation. The rms nonuniformity of microtarget irradiance was estimated at {approx}60 %. (interaction of laser radiation with targets)

  14. Electrode system for electric-discharge generation of atomic iodine in a repetitively pulsed oxygen - iodine laser with a large active volume

    SciTech Connect

    Kazantsev, S Yu; Kononov, I G; Podlesnykh, S V; Firsov, K N

    2010-08-03

    Possibilities for increasing the active medium volume of a chemical oxygen - iodine laser (CCOIL) with a pulsed electric-discharge generation of atomic iodine are studied. The reasons are analysed of the low stability of the transverse self-sustained volume discharge in electrode systems with metal cathodes under the conditions of the electric energy input into gas-discharge plasma that are typical for CCOILs: low pressure of mixtures containing a strongly electronegative component, low voltage of discharge burning, low specific energy depositions, and long duration of the current pulse. An efficient electrode system is elaborated with the cathode based on an anisotropically-resistive material, which resulted in a stable discharge in the mixtures of iodide (CH{sub 3}I, n-C{sub 3}H{sub 7}I, C{sub 2}H{sub 5}I) with oxygen and nitrogen at the specific energy depositions of {approx}5 J L{sup -1}, pressures of 10 - 25 Torr, and mixture volume of 2.5 L. (lasers)

  15. Multiphase reacting flow modeling of singlet oxygen generators for chemical oxygen iodine lasers.

    SciTech Connect

    Salinger, Andrew Gerhard; Pawlowski, Roger Patrick; Hewett, Kevin B.; Madden, Timothy J.; Musson, Lawrence Cale

    2008-08-01

    Singlet oxygen generators are multiphase flow chemical reactors used to generate energetic oxygen to be used as a fuel for chemical oxygen iodine lasers. In this paper, a theoretical model of the generator is presented along with its solutions over ranges of parameter space and oxygen maximizing optimizations. The singlet oxygen generator (SOG) is a low-pressure, multiphase flow chemical reactor that is used to produce molecular oxygen in an electronically excited state, i.e. singlet delta oxygen. The primary product of the reactor, the energetic oxygen, is used in a stage immediately succeeding the SOG to dissociate and energize iodine. The gas mixture including the iodine is accelerated to a supersonic speed and lased. Thus the SOG is the fuel generator for the chemical oxygen iodine laser (COIL). The COIL has important application for both military purposes--it was developed by the US Air Force in the 1970s--and, as the infrared beam is readily absorbed by metals, industrial cutting and drilling. The SOG appears in various configurations, but the one in focus here is a crossflow droplet generator SOG. A gas consisting of molecular chlorine and a diluent, usually helium, is pumped through a roughly rectangular channel. An aqueous solution of hydrogen peroxide and potassium hydroxide is pumped through small holes into the channel and perpendicular to the direction of the gas flow. So doing causes the solution to become aerosolized. Dissociation of the potassium hydroxide draws a proton from the hydrogen peroxide generating an HO{sub 2} radical in the liquid. Chlorine diffuses into the liquid and reacts with the HO{sub 2} ion producing the singlet delta oxygen; some of the oxygen diffuses back into the gas phase. The focus of this work is to generate a predictive multiphase flow model of the SOG in order to optimize its design. The equations solved are the so-called Eulerian-Eulerian form of the multiphase flow Navier-Stokes equations wherein one set of the

  16. Subwavenumber charge-coupled device spectrometer calibration using molecular iodine laser-induced fluorescence

    SciTech Connect

    Lambert, Joseph G.; Hernandez-Diaz, Carlos; Williamson, J. Charles

    2010-01-15

    Spectrometers configured with charge-coupled devices (CCD) or other array-based detectors require calibration to convert from the pixel coordinate to a spectral coordinate. A CCD calibration method well suited for Raman spectroscopy has been developed based on the 514.5 nm Ar{sup +} laser-induced fluorescence (LIF) spectrum of room-temperature molecular iodine vapor. Over 360 primary and secondary I{sub 2} LIF calibration lines spanning 510-645 nm were identified as calibrant peaks using an instrumental resolution of 1 cm{sup -1}. Two instrument calibration functions were evaluated with these peaks: a second-order polynomial and a function derived from simple optomechanical considerations. The latter function provided better fitting characteristics. Calibration using I{sub 2} LIF was tested with measurements of both laser light scattering and Raman spectra. The I{sub 2} LIF reference spectra and the signal spectra were recorded simultaneously, with no cross talk, by separating the two signals spatially along the vertical axis of the CCD imager. In this way, every CCD image could be independently calibrated. An accuracy and a precision of {+-}0.05 cm{sup -1} were achieved with this calibration technique.

  17. Realization of an advanced nozzle concept for compact chemical oxygen iodine laser

    NASA Astrophysics Data System (ADS)

    Singhal, Gaurav; Subbarao, P. M. V.; Rajesh, R.; Mainuddin; Tyagi, R. K.; Dawar, A. L.

    2007-04-01

    Conventional supersonic chemical oxygen-iodine lasers (SCOIL) are not only low-pressure systems, with cavity pressure of 2-3 Torr and Mach number of approximately 1.5, but also are high-throughput systems with a typical laser power per unit evacuation capacity of nearly 1 J/l, thus demanding high capacity vacuum systems which mainly determine the compactness of the system. These conventional nozzle-based systems usually require a minimum of a two-stage ejector system for realization of atmospheric pressure recovery in a SCOIL. Typically for a 500 W class SCOIL, a first stage requires a motive gas flow (air) of 120 gm/s to entrain a laser gas flow of 3 g/s and is capable of achieving the pressure recovery in the range of 60-80 Torr. On the other hand, the second stage ejector requires 4.5 kg/s of motive gas (air) to achieve atmospheric pressure recovery. An advanced nozzle, also known as ejector nozzle, suitable for a 500 W-class SCOIL employing an active medium flow of nearly 12 g/s, has been developed and used instead of a conventional slit nozzle. The nozzle has been tested in both cold as well as hot run conditions of SCOIL, achieving a typical cavity pressure of nearly 10 Torr, stagnation pressure of approximately 85 Torr and a cavity Mach number of 2.5. The present study details the gas dynamic aspects of this ejector nozzle and highlights its potential as a SCOIL pressure recovery device. This nozzle in conjunction with a diffuser is capable of achieving pressure recovery equivalent to a more cumbersome first stage of the pressure recovery system used in the case of a conventional slit nozzle-based system. Thus, use of this nozzle in place of a conventional slit nozzle can achieve atmospheric discharge using a single stage ejector system, thereby making the pressure recovery system quite compact.

  18. Flowfield measurements in a model scramjet combustion using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Mcdaniel, J. C., Jr.

    1984-01-01

    Preliminary designs were completed for an iodine mixing chamber and the optical setup to be used with a modified wind tunnel in obtaining accurate, spatially resolved measurements of variables in the flowfield of a model nonreacting scramjet combustor. Schematics of the iodine-seeded wind tunnel and a sketch of the charcoal filter for removing the iodine are included along with a cutaway section of the laboratory.

  19. Singlet oxygen generation in gas discharge for oxygen-iodine laser pumping

    NASA Astrophysics Data System (ADS)

    Lopaev, D. V.; Braginsky, O. V.; Klopovsky, K. S.; Kovalev, A. S.; Mankelevich, Yu. A.; Popov, N. A.; Rakhimov, A. T.; Rakhimova, T. V.; Vasilieva, A. N.

    2004-09-01

    The possibility of development of effective discharged singlet oxygen (SO) generator (DSOG) for oxygen-iodine laser (OIL) is studied in detail. Researches of kinetics of oxygen atoms and oxygen molecules in the lowest metastable singlet states have been carried out in the different discharges and its afterglow (DC discharges, E-beam controlled discharge and RF discharges) in both CW and pulsed mode in a wide range of conditions (pressures, gas mixtures, energy deposits etc.). The models developed for all the discharges have allowed us to analyze SO generation and loss mechanisms and to find out the key-parameters controlling the highest SO yield. It is shown that in addition to spatial plasma uniformity at low E/N and high specific energy deposit per oxygen molecule, DSOG must be oxygen atom free to avoid fast three-body quenching of SO by atomic oxygen with increasing pressure and thereby to provide pressure scaling (in tens Torrs) for applying to real OIL systems.

  20. Computer-controlled multi-parameter mapping of 3D compressible flowfields using planar laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Donohue, James M.; Victor, Kenneth G.; Mcdaniel, James C., Jr.

    1993-01-01

    A computer-controlled technique, using planar laser-induced iodine fluorescence, for measuring complex compressible flowfields is presented. A new laser permits the use of a planar two-line temperature technique so that all parameters can be measured with the laser operated narrowband. Pressure and temperature measurements in a step flowfield show agreement within 10 percent of a CFD model except in regions close to walls. Deviation of near wall temperature measurements from the model was decreased from 21 percent to 12 percent compared to broadband planar temperature measurements. Computer-control of the experiment has been implemented, except for the frequency tuning of the laser. Image data storage and processing has been improved by integrating a workstation into the experimental setup reducing the data reduction time by a factor of 50.

  1. Optical Frequency Metrology of an Iodine-Stabilized He-Ne Laser Using the Frequency Comb of a Quantum-Interference-Stabilized Mode-Locked Laser

    PubMed Central

    Smith, Ryan P.; Roos, Peter A.; Wahlstrand, Jared K.; Pipis, Jessica A.; Rivas, Maria Belmonte; Cundiff, Steven T.

    2007-01-01

    We perform optical frequency metrology of an iodine-stabilized He-Ne laser using a mode-locked Ti:sapphire laser frequency comb that is stabilized using quantum interference of photocurrents in a semiconductor. Using this technique, we demonstrate carrier-envelope offset frequency fluctuations of less than 5 mHz using a 1 s gate time. With the resulting stable frequency comb, we measure the optical frequency of the iodine transition [127I2 R(127) 11-5 i component] to be 473 612 214 712.96 ± 0.66 kHz, well within the uncertainty of the CIPM recommended value. The stability of the quantum interference technique is high enough such that it does not limit the measurements. PMID:27110472

  2. Influence of the gaseous mixture composition on accuracy of molecular iodine on-line detection by laser-induced fluorescence method

    NASA Astrophysics Data System (ADS)

    Kireev, S. V.; Shnyrev, S. L.

    2016-07-01

    This paper informs on research into the influence of the composition of gaseous mixtures analyzed on the accuracy of on-line molecular iodine detection by laser-induced fluorescence in various gaseous media—in atmospheric air and in technological mixtures formed during reprocessing of spent nuclear fuel. The paper shows that by considering the composition of buffer media and parts of its components, the accuracy of iodine content measurement may be increased in several times.

  3. Analytic study of the chain dark decomposition reaction of iodides - atomic iodine donors - in the active medium of a pulsed chemical oxygen-iodine laser: 2. Limiting parameters of the branching chain dark decomposition reaction of iodides

    SciTech Connect

    Andreeva, Tamara L; Kuznetsova, S V; Maslov, Aleksandr I; Sorokin, Vadim N

    2009-08-31

    The final stages in the development of a branching chain decomposition reaction of iodide in the active medium of a pulsed chemical oxygen-iodine laser (COIL) are analysed. Approximate expressions are derived to calculate the limiting parameters of the chain reaction: the final degree of iodide decomposition, the maximum concentration of excited iodine atoms, the time of its achievement, and concentrations of singlet oxygen and iodide at that moment. The limiting parameters, calculated by using these expressions for a typical composition of the active medium of a pulsed COIL, well coincide with the results of numerical calculations. (active media)

  4. Planar measurement of flow field parameters in a nonreacting supersonic combustor using laser-induced iodine fluorescence

    NASA Technical Reports Server (NTRS)

    Hartfield, Roy J., Jr.; Hollo, Steven D.; Mcdaniel, James C.

    1990-01-01

    A nonintrusive optical technique, laser-induced iodine fluorescence, has been used to obtain planar measurements of flow field parameters in the supersonic mixing flow field of a nonreacting supersonic combustor. The combustor design used in this work was configured with staged transverse sonic injection behind a rearward-facing step into a Mach 2.07 free stream. A set of spatially resolved measurements of temperature and injectant mole fraction has been generated. These measurements provide an extensive and accurate experimental data set required for the validation of computational fluid dynamic codes developed for the calculation of highly three-dimensional combustor flow fields.

  5. On-line molecular iodine isotopologue detection in gaseous media during spent nuclear fuel reprocessing using a laser-induced fluorescence method

    NASA Astrophysics Data System (ADS)

    Kireev, S. V.; Shnyrev, S. L.

    2015-06-01

    The paper reports on on-line measurement of the {}129{{\\text{I}}2}, 127I129I, and {}127{{\\text{I}}2} concentrations during spent nuclear fuel (SNF) reprocessing using a laser-induced fluorescence method. A He-Ne laser (632.8 nm) was used as a fluorescence excitation source. The detection limits obtained for molecular iodine isotopologue concentrations demonstrate the possibility of using this method for iodine control both in gaseous technological media generated during SNF reprocessing and after passing through the gas purification system (in atmosphere emission).

  6. Small acousto-optic modulation for active mode locking in the iodine photodissociation laser and the effect of supplementary saturable absorber

    SciTech Connect

    Kim, Y.S.; Lee, S.S.

    1985-02-01

    Active, passive, and active--passive mode locking of the iodine photodissociation laser are investigated. The peak-to-background ratio (PBR) of the acousto-optically mode-locked pulse is 85% for rf power of 5 W. Passive mode locking using BDN dye gives PBR of 75% and has inferior reproducibility. The active--passive mode locking using the two methods simultaneously is useful for the pressure broadened iodine laser line and gives a PBR of 91%. In this case the rf power required for complete mode locking is calculated to be 7 W which is much less than the required power of 11 W in using active mode locking alone.

  7. 2D gasdynamic simulation of the kinetics of an oxygen-iodine laser with electric-discharge generation of singlet oxygen

    SciTech Connect

    Chukalovsky, A. A.; Rakhimova, T. V.; Klopovsky, K. S.; Mankelevich, Yu. A.; Proshina, O. V.

    2011-03-15

    The kinetic processes occurring in an electric-discharge oxygen-iodine laser are analyzed with the help of a 2D (r, z) gasdynamic model taking into account transport of excited oxygen, singlet oxygen, and radicals from the electric discharge and their mixing with the iodine-containing gas. The main processes affecting the dynamics of the gas temperature and gain are revealed. The simulation results obtained using the 2D model agree well with the experimental data on the mixture gain. A subsonic oxygen-iodine laser in which singlet oxygen is generated by a 350 W transverse RF discharge excited in an oxygen flow at a pressure P = 10 Torr and the discharge tube wall is covered with mercury oxide is simulated. The simulated mixing system is optimized in terms of the flow rate and the degree of preliminary dissociation of the iodine flow. The optimal regime of continuous operation of a subsonic electric-discharge oxygen-iodine laser is found.

  8. Iodine poisoning

    MedlinePlus

    Iodine is a naturally occurring chemical. Small amounts are needed for good health. However, large doses can ... Children are especially sensitive to the effects of iodine. NOTE: Iodine is found in certain foods. However, ...

  9. 70-J repped pulse (0.5 Hz) closed-cycle photolytic atomic iodine laser at 1.315 microns with excellent BQ, coherence length, and reliable operation

    NASA Astrophysics Data System (ADS)

    Schlie, L. A. V.; Rathge, Robert D.

    1992-05-01

    The performance of a repetitively pulsed, high energy, closed cycle photolytic atomic iodine lasers at 1.315 microns is presented. Using an I2 removal system for the photolyzed C3F7I laser fuel, more than 70 joules/pulse was acquired in the fundamental mode from a M equals 3 confocal unstable resonator at a 0.5 Hz repetition rate. The closed cycle chemical scrubber system consisted of a condensative-evaporative section, two Cu wool I2 reactor sections, and an internal turbo-blower. This closed cycle system provided C2F7I gas at 10 - 60 torr absent of I2. The turbo-blower produced longitudinal flow velocities greater than 10 m/s through the 150 cm long by 7.5 X 7.5 cm2 cross sectional photolytic iodine gain region. In addition to the high energy output, the resulting 10 - 12 microsecond(s) ec laser had a beam quality of less than 1.5 times diffraction limited with a coherence length greater than 45 meters, and a polarization extinction ratio better than 100:1. Projections from this pulsed photolytic atomic iodine laser technology to larger energies, high repetition rates, and variable pulsewidths are discussed. In addition, the performance of cw photolytically excited atomic iodine laser at 1.315 micrometers is reported which has excellent scaling potential. Volumetric extractable cw powers of 55 watts/liter are reported with a small signal gain coefficient of 2%/cm. The potential of enhancing the cw powers to kilowatt levels plus producing variable pulsewidth, repetition rate iodine laser using an internal electro-optical modulator are also discussed.

  10. Oxygen discharge and post-discharge kinetics experiments and modeling for the electric oxygen-iodine laser system.

    PubMed

    Palla, A D; Zimmerman, J W; Woodard, B S; Carroll, D L; Verdeyen, J T; Lim, T C; Solomon, W C

    2007-07-26

    Laser oscillation at 1315 nm on the I(2P1/2)-->I(2P3/2) transition of atomic iodine has been obtained by a near resonant energy transfer from O2(a1Delta) produced using a low-pressure oxygen/helium/nitric oxide discharge. In the electric discharge oxygen-iodine laser (ElectricOIL) the discharge production of atomic oxygen, ozone, and other excited species adds levels of complexity to the singlet oxygen generator (SOG) kinetics which are not encountered in a classic purely chemical O2(a1Delta) generation system. The advanced model BLAZE-IV has been introduced to study the energy-transfer laser system dynamics and kinetics. Levels of singlet oxygen, oxygen atoms, and ozone are measured experimentally and compared with calculations. The new BLAZE-IV model is in reasonable agreement with O3, O atom, and gas temperature measurements but is under-predicting the increase in O2(a1Delta) concentration resulting from the presence of NO in the discharge and under-predicting the O2(b1Sigma) concentrations. A key conclusion is that the removal of oxygen atoms by NOX species leads to a significant increase in O2(a1Delta) concentrations downstream of the discharge in part via a recycling process; however, there are still some important processes related to the NOX discharge kinetics that are missing from the present modeling. Further, the removal of oxygen atoms dramatically inhibits the production of ozone in the downstream kinetics. PMID:17461557

  11. Reduced dimer production in solar-simulator-pumped continuous wave iodine lasers based on model simulations and scaling and pumping studies

    NASA Technical Reports Server (NTRS)

    Costen, Robert C.; Heinbockel, John H.; Miner, Gilda A.; Meador, Willard E., Jr.; Tabibi, Bagher M.; Lee, Ja H.; Williams, Michael D.

    1995-01-01

    A numerical rate equation model for a continuous wave iodine laser with longitudinally flowing gaseous lasant is validated by approximating two experiments that compare the perfluoroalkyl iodine lasants n-C3F7I and t-C4F9I. The salient feature of the simulations is that the production rate of the dimer (C4F9)2 is reduced by one order of magnitude relative to the dimer (C3F7)2. The model is then used to investigate the kinetic effects of this reduced dimer production, especially how it improves output power. Related parametric and scaling studies are also presented. When dimer production is reduced, more monomer radicals (t-C4F9) are available to combine with iodine ions, thus enhancing depletion of the laser lower level and reducing buildup of the principal quencher, molecular iodine. Fewer iodine molecules result in fewer downward transitions from quenching and more transitions from stimulated emission of lasing photons. Enhanced depletion of the lower level reduces the absorption of lasing photons. The combined result is more lasing photons and proportionally increased output power.

  12. Laser and solar-photovoltaic space power systems comparison. II.

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Stripling, J.; Enderson, T. M.; Humes, D. H.; Davis, W. T.

    1984-01-01

    A comparison of total system cost is made between solar photovoltaic and laser/receiver systems. The laser systems assume either a solar-pumped CO2 blackbody transfer laser with MHD receiver or a solar pumped liquid neodymium laser with a photovoltaic receiver. Total system costs are less for the laser systems below 300 km where drag is significant. System costs are highly dependent on altitude.

  13. Data acquisition and control system with a programmable logic controller (PLC) for a pulsed chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Yu, Haijun; Li, Guofu; Duo, Liping; Jin, Yuqi; Wang, Jian; Sang, Fengting; Kang, Yuanfu; Li, Liucheng; Wang, Yuanhu; Tang, Shukai; Yu, Hongliang

    2015-02-01

    A user-friendly data acquisition and control system (DACS) for a pulsed chemical oxygen -iodine laser (PCOIL) has been developed. It is implemented by an industrial control computer,a PLC, and a distributed input/output (I/O) module, as well as the valve and transmitter. The system is capable of handling 200 analogue/digital channels for performing various operations such as on-line acquisition, display, safety measures and control of various valves. These operations are controlled either by control switches configured on a PC while not running or by a pre-determined sequence or timings during the run. The system is capable of real-time acquisition and on-line estimation of important diagnostic parameters for optimization of a PCOIL. The DACS system has been programmed using software programmable logic controller (PLC). Using this DACS, more than 200 runs were given performed successfully.

  14. Three-block model of the kinetics of vibrationally excited I{sub 2}(X) molecules in the active media of oxygen - iodine lasers

    SciTech Connect

    Pichugin, S Yu

    2012-09-30

    A three-block model of the kinetics of vibrationally excited I{sub 2}(X) molecules in the active media of chemical oxygen - iodine lasers is developed. Instead of the system of equations describing a change in the concentrations of I{sub 2}(X, u) (u=0 - 47) molecules, this model uses equations for the total concentrations of iodine molecules belonging to the blocks of vibrational levels with u {<=} 10, u = 11 - 24, and u {>=} 25. Effective deactivation rate constants of I{sub 2}(X, 11 {<=} u {<=} 24) molecules are found for laser media of different compositions. The results of calculations performed using the proposed model agree with experimental data and are close to the parameters calculated previously by using the total system of equations for populations of individual vibrational levels of I{sub 2}(X, u). (laser applications and other topics in quantum electronics)

  15. Zeeman effects in the hyperfine structure of atomic iodine photodissociation laser emission.

    NASA Technical Reports Server (NTRS)

    Hwang, W. C.; Kasper, J. V. V.

    1972-01-01

    Observation of hyperfine structure in laser emission from CF3I and C2F5I photodissociation lasers. Constant magnetic fields affect the time behavior of the emission by changing the relative gains of the hyperfine transitions. Time-varying fields usually present in photodissociation lasers further complicate the emission.

  16. Investigation of possibilities for solar-powered high-energy lasers in space

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Solar pumped lasers were investigated. The literature was reviewed for possible solar laser candidates from optical pumping experiments. A baseline CO electric discharge laser system was shown to be technically feasible. The most promising direct solar pumped laser was identified to be CF3I. Using the 'STAG' solar laser concept and CF3I, it was found that such a system could be weight competitive with the baseline CO laser system.

  17. Iodine poisoning

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002658.htm Iodine poisoning To use the sharing features on this page, please enable JavaScript. Iodine is a naturally occurring chemical. Small amounts are ...

  18. Laser power transmission

    NASA Technical Reports Server (NTRS)

    Conway, Edmund J.

    1992-01-01

    An overview of previous studies related to laser power transmission is presented. Particular attention is given to the use of solar pumped lasers for space power applications. Three general laser mechanisms are addressed: photodissociation lasing driven by sunlight, photoexcitation lasing driven directly by sunlight, and photoexcitation lasing driven by thermal radiation.

  19. Efficient laser action on the 342-nm band of molecular iodine using ArF laser pumping

    NASA Astrophysics Data System (ADS)

    Shaw, M. J.; Edwards, C. B.; Oneill, F.; Fotakis, C.; Donovan, R. J.

    1980-08-01

    Strong laser action on the 342-nm band of I2 has been obtained by transverse pumping I2/SF6 mixtures at 193 nm with an ArF laser. The highest output energy obtained was 230 mJ at an intrinsic energy conversion efficiency of approximately 30% equivalent to a photon efficiency of greater than 50%.

  20. Interpretation of In-Situ Measurements of Iodine Monoxide in Coastal Regions Using Laser-Induced Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Furneaux, K. L.; Whalley, L. K.; Heard, D. E.

    2009-04-01

    Iodine species are present in coastal and open ocean regions due to the release of I2 and iodocarbons from macro and micro algae. The photolysis of these molecules yields iodine atoms, which react with ozone to produce iodine monoxide (IO). IO is involved in ozone depletion cycles, the partitioning of HOx and NOx, and the formation and growth of new particles. A novel point source Laser Induced Fluorescence (LIF) instrument was deployed to measure IO in September 2006 at Roscoff, France as part of the Reactive Halogens in the Marine Boundary Layer (RHaMBLe) programme (1 instrument uncertainty = 23%)1. The maximum IO mixing ratio was 30 ± 7.1 pptV (10 s integration period, limit of detection = 1.4 pptV) at this semi-polluted coastal site (NOx levels = 1 - 5 ppbV). The closest macroalgae beds known to strongly emit I2 (laminaria) were ~ 300 m from the LIF instrument. IO displayed a strong anti-correlation with tidal height which is consistent with previous studies. IO was also dependent on solar irradiation and meteorological conditions. The dominant source of IO at this site was the photolysis of I2. The measurements provided by this instrument aim to address the main uncertainties associated with iodine chemistry. Co-ordinated measurement of IO by point source (LIF) and spatially averaged (Long Path Differential Optical Absorption Spectroscopy) instruments confirm the presence of IO hotspots due to non-uniform macroalgae distribution at this location (resulting in a spatially variable I2 source). The ratio of point source/spatially averaged IO is determined by meteorological conditions and distance of the instrument from macroalgae beds. Co-located point source I2 (Broadband Cavity Ringdown Spectroscopy) and IO (LIF) measurements correlated on some days but cannot be explained by our current knowledge of iodine chemistry. The influence of NOx on IO has been investigated. The detection of IO by LIF at the Roscoff site shows that IO can survive in a high NOx

  1. PHYSICAL PHENOMENA ACCOMPANYING THE GENERATION AND AMPLIFICATION OF LASER RADIATION: Investigation of elementary stages of the CF3 + I + M → CF3I + M recombination process using an iodine photodissociation laser

    NASA Astrophysics Data System (ADS)

    Kuznetsova, S. V.; Maslov, A. I.

    1989-05-01

    Measurements were made of the rate constant of the CF3 + I + M→CF3I + M recombination process as a function of the pressure of various buffer gases (M = Xe, SF6, CF3I, C5F12). An analysis was made of a method of measuring the recombination rate constants for perfluoroalkyl radicals using an iodine laser developed previously and improved in the present study. The main parameters of the elementary stages of the recombination process involving CF3 radicals and ground-state iodine atoms were determined from the dependences k( [M] ) using formulas from the simplified theory of monomolecular decay.

  2. Toward understanding the dissociation of I2 in chemical oxygen-iodine lasers: Combined experimental and theoretical studies

    NASA Astrophysics Data System (ADS)

    Waichman, K.; Rybalkin, V.; Katz, A.; Dahan, Z.; Barmashenko, B. D.; Rosenwaks, S.

    2007-07-01

    The dissociation of I2 molecules at the optical axis of a supersonic chemical oxygen-iodine laser (COIL) was studied via detailed measurements and three-dimensional computational fluid dynamics calculations. The measurements, briefly reported in a recent paper [Rybalkin et al., Appl. Phys. Lett. 89, 021115 (2006)] and reanalyzed in detail here, revealed that the number N of consumed O2(aΔg1) molecules per dissociated I2 molecule depends on the experimental conditions: it is 4.5±0.4 for typical conditions and I2 densities applied for optimal operation of the COIL but increases at lower I2 densities. Comparing the measurements and the calculations enabled critical examination of previously proposed dissociation mechanisms and suggestion of a mechanism consistent with the experimental and theoretical results obtained in a supersonic COIL for the gain, temperature, I2 dissociation fraction, and N at the optical axis. The suggested mechanism combines the recent scheme of Azyazov and Heaven [AIAA J. 44, 1593 (2006)], where I2(A'Π2u3), I2(AΠ1u3), and O2(aΔg1,v) are significant dissociation intermediates, with the "standard" chain branching mechanism of Heidner III et al. [J. Phys. Chem. 87, 2348 (1983)], involving I(P1/22) and I2(XΣg +1,v).

  3. Dissociation of I II in chemical oxygen-iodine lasers: experiment, modeling, and pre-dissociation by electrical discharge

    NASA Astrophysics Data System (ADS)

    Katz, A.; Waichman, K.; Dahan, Z.; Rybalkin, V.; Barmashenko, B. D.; Rosenwaks, S.

    2007-06-01

    The dissociation of I II molecules at the optical axis of a supersonic chemical oxygen-iodine laser (COIL) was studied via detailed measurements and three dimensional computational fluid dynamics calculations. Comparing the measurements and the calculations enabled critical examination of previously proposed dissociation mechanisms and suggestion of a mechanism consistent with the experimental and theoretical results obtained in a supersonic COIL for the gain, temperature and I II dissociation fraction at the optical axis. The suggested mechanism combines the recent scheme of Azyazov and Heaven (AIAA J. 44, 1593 (2006)), where I II(A' 3Π 2u), I II(A 3Π 1u) and O II(a1Δ g, v) are significant dissociation intermediates, with the "standard" chain branching mechanism of Heidner et al. (J. Phys. Chem. 87, 2348 (1983)), involving I(2P 1/2) and I II(X1Σ + g, v). In addition, we examined a new method for enhancement of the gain and power in a COIL by applying DC corona/glow discharge in the transonic section of the secondary flow in the supersonic nozzle, dissociating I II prior to its mixing with O II(1Δ). The loss of O II(1Δ) consumed for dissociation was thus reduced and the consequent dissociation rate downstream of the discharge increased, resulting in up to 80% power enhancement. The implication of this method for COILs operating beyond the specific conditions reported here is assessed.

  4. Picosecond dynamics of reactions in the liquid phase: studies of iodine photodissociation and development of new laser techniques

    SciTech Connect

    Berg, M.A.

    1985-09-01

    Iodine photodissociation and recombination was studied as a model for processes common to chemical reaction in the liquid phase. Picosecond transient absorption measurements from 1000 to 295 nm were used to monitor the dynamics in a variety of solvents. Most of the atoms which undergo geminate recombination were found to do so in less than or equal to 15 ps, in agreement with the results of existing molecular dynamics simulations. Vibrational relaxation times vary from approx.15 ps near the middle of the ground state well to approx.150 ps for complete relaxation to v = 0. The prediction of strong resonant vibrational energy transfer to chlorinated methane solvents was not supported, but some evidence for this mechanism was found for alkane solvents. Current theory is unable to explain the large variation (65 to 2700 ps) of the excited A'-state lifetime in various solvents. The 10-Hz amplified, synchronously-pumped dye laser which was used in these studies is described and characterized. SERS (Stimulated Electronic Raman Scattering) and difference frequency mixing were used in the generation of the infrared and far-infrared, respectively. 54 refs., 38 figs., 3 tabs. (WRF)

  5. Carrier phases for iodine in the Allende meteorite and their associated Xe-129(r)/I-127 ratios - A laser microprobe study

    NASA Technical Reports Server (NTRS)

    Kirschbaum, C.

    1988-01-01

    This paper presents the results of a study of the carrier phases of iodine in the Allende meteorite and their associated Xe-129(r)/I-127 ratios, obtained using a new high-sensitivity low-blank mass spectrometer coupled with a low-blank laser extraction system. Two types of experiments were performed: a survey of the Xe-129(r) amounts in unirradiated specimens of fine-grained assemblages and individual coarse mineral grains, and a study of the relationship between chlorine and iodine in irradiated samples of the inclusions, in which the Xe-129(r)/I-127 ratios were determined for various minerals. As a by-product of these measurements, the Ar-40/Ar-39 ages were obtained along with some results on trapped Xe components. A schematic diagram of the new mass spectrometer system is included.

  6. Generation of singlet oxygen for an oxygen-iodine laser in a radio-frequency discharge

    SciTech Connect

    Braginskii, O V; Vasil'eva, A N; Klopovskii, K S; Kovalev, A S; Lopaev, D V; Mankelevich, Yu A; Popov, N A; Rakhimov, Aleksandr T; Rakhimova, T V

    2005-01-31

    The generation of singlet oxygen (SO) in a radio-frequency discharge (13.56 MHz) in the gas flow was investigated experimentally and theoretically. The oxygen pressure was varied from 2 to 20 Torr and the energy deposition in gas from 10 to 2000 J mmol{sup -1}. The saturation of the SO concentration with increasing the energy deposition was shown to arise from the three-body process of SO quenching by atomic oxygen. Removing atomic oxygen allowed a 2.5-fold increase in the ultimate SO concentration at the discharge output. For an oxygen pressure of 15 Torr, the SO fraction amounts to 10%. (active media. lasers)

  7. Kinetics and scaling of gain and lasing in a 1-5 kW microwave discharge oxygen iodine laser

    NASA Astrophysics Data System (ADS)

    Rawlins, Wilson T.; Lee, Seonkyung; Hicks, Adam J.; Konen, Ian M.; Plumb, Emily P.; Oakes, David B.; Davis, Steven J.

    2010-02-01

    Scaling of Electric Oxygen-Iodine Laser (EOIL) systems to higher powers requires extension of electric discharge powers into the kW range and beyond, with high efficiency and singlet oxygen yield. This paper describes the implementation of a moderate-power (1 to 5 kW) microwave discharge at 30 to 70 Torr pressure in a supersonic flow reactor designed for systematic investigations of the scaling of gain and lasing with power and flow conditions. The 2450 MHz microwave discharge is confined near the flow axis by a swirl flow. The discharge effluent, containing active species including O2(a1▵), O(3P), and O3, passes through a 2-D flow duct equipped with a supersonic nozzle and cavity. I2 is injected upstream of the supersonic nozzle. The apparatus is water-cooled, and is modular to permit a variety of inlet, nozzle, and optical configurations. A comprehensive suite of optical emission and absorption diagnostics monitors the absolute concentrations of O2(a), O(3P), O3, I2, I(2P3/2), I(2P1/2), small-signal gain, and temperature in both the subsonic and supersonic flow streams. The experimental results include numerous observations of positive gain and lasing in supersonic flow, and the scaling of gain with a variety of flow and reaction rate conditions. The results are compared with kinetics modeling predictions to highlight key discrepancies as well as areas of agreement. The observed gains are generally lower than the predicted values, due in part to chemical kinetics effects and also due to mixing limitations specific to the reagent injection design. We discuss in detail the observed effects related to O-atom chemistry, and their import for scaling the gain to higher levels. We also will present initial beam quality measurements.

  8. Kinetic-fluid dynamics modeling of I{sub 2} dissociation in supersonic chemical oxygen-iodine lasers

    SciTech Connect

    Waichman, K.; Barmashenko, B. D.; Rosenwaks, S.

    2009-09-15

    The mechanism of I{sub 2} dissociation in supersonic chemical oxygen-iodine lasers (COILs) is studied applying kinetic-fluid dynamics modeling, where pathways involving the excited species I{sub 2}(X {sup 1}SIGMA{sub g}{sup +},10<=v<25), I{sub 2}(X {sup 1}SIGMA{sub g}{sup +},25<=v<=47), I{sub 2}(A{sup '} {sup 3}PI{sub 2u}), I{sub 2}(A {sup 3}PI{sub 1u}), O{sub 2}(X {sup 3}SIGMA{sub g}{sup -},v), O{sub 2}(a {sup 1}DELTA{sub g},v), O{sub 2}(b {sup 1}SIGMA{sub g}{sup +},v), and I({sup 2}P{sub 1/2}) as intermediate reactants are included. The gist of the model is adding the first reactant and reducing the contribution of the second as compared to previous models. These changes, recently suggested by Azyazov, et al. [J. Chem. Phys. 130, 104306 (2009)], significantly improve the agreement with the measurements of the gain in a low pressure supersonic COIL for all I{sub 2} flow rates that have been tested in the experiments. In particular, the lack of agreement for high I{sub 2} flow rates, which was encountered in previous models, has been eliminated in the present model. It is suggested that future modeling of the COIL operation should take into account the proposed contribution of the above mentioned reactants.

  9. LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Effect of intense background radiation on the sensitivity of a laser receiver with an iodine active quantum filter

    NASA Astrophysics Data System (ADS)

    Kutaev, Yu F.; Mankevich, S. K.; Nosach, O. Yu; Orlov, E. P.

    2002-04-01

    The effect of background light on the sensitivity of a laser receiver with an iodine active quantum filter (λ=1.315 μm) was theoretically and experimentally investigated. Upon the reception of a 40-ns pulsed signal against the background of 2.5-fold attenuated radiation of a pulsed light source with a brightness temperature of 4 × 104 K, the sensitivity of this receiver for a signal-to-noise ratio of three and a diffraction-limited acceptance angle was experimentally shown to be equal to 20 photons, which exceeds the quantum limit by about a factor of two. This is consistent with the results of theoretical treatment and suggests that upon the detection of optical signals against the background of the solar disk, the sensitivity of this receiver should decrease by only 12%. This receiver was compared with a receiver employing a photomultiplier of the visible range. Upon the reception of optical signals with the same parameters against the background of the solar disk and an interference filter with a transmission band width of 5 nm, the sensitivity of a receiver equipped with an FEU-115 photomultiplier was shown to be equal to about 1400 photons for a signal-to-noise ratio of three.

  10. Planar Laser-Induced Iodine Fluorescence Measurements in Rarefied Hypersonic Flow

    NASA Technical Reports Server (NTRS)

    Cecil, Eric; McDaniel, James C.

    2005-01-01

    A planar laser-induced fluorescence (PLIF) technique is discussed and applied to measurement of time-averaged values of velocity and temperature in an I(sub 2)-seeded N(sub 2) hypersonic free jet facility. Using this technique, a low temperature, non-reacting, hypersonic flow over a simplified model of a reaction control system (RCS) was investigated. Data are presented of rarefied Mach 12 flow over a sharp leading edge flat plate at zero incidence, both with and without an interacting jet issuing from a nozzle built into the plate. The velocity profile in the boundary layer on the plate was resolved. The slip velocity along the plate, extrapolated from the velocity profile data, varied from nearly 100% down to 10% of the freestream value. These measurements are compared with results of a DSMC solution. The velocity variation along the centerline of a jet issuing from the plate was measured and found to match closely with the correlation of Ashkenas and Sherman. The velocity variation in the oblique shock terminating the jet was resolved sufficiently to measure the shock wave thickness.

  11. Comparison of laser models

    NASA Technical Reports Server (NTRS)

    Heinbockel, John H.

    1992-01-01

    The final phase of modeling solar pumped lasers considers the photodissociation of the perfloralkyl molecules n - C3F7I ,t - C4F9I, and i - C3F7I. Computer modeling was compared to laboratory data and good agreement between theory and experiment was achieved. The following is a summary of the modeling of solar pumped lasers. A perfloride gas enters a tube at a point z = 0 and travels a distance L at a velocity, W, and then exits at the point z = L. During the flow, the gas is solar pumped over the initial distance 0 less than or = z less than or = z sub 0, where z sub 0 is less than or equal to L. The perfloride gas interacts chemically with light and a chain of chemical reactions occur.

  12. In-situ measurements of iodine monoxide at coastal and open-ocean locations using laser induced fluorescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Commane, R.; Whalley, L. K.; Furneaux, K. L.; Ingham, T.; Bloss, W. J.; Heard, D. E.

    2008-12-01

    The halogen oxides, IO and BrO, have traditionally been measured using the Long Path-Differential Optical Absorption Spectroscopy (LP-DOAS) technique. Laser Induced Fluorescence (LIF), however, provides a sensitive and selective alternative method to detect IO. LIF provides a point-source measurement of IO; comparison of IO data taken using LIF and LP-DOAS can help determine local sources of iodine at coastal sites. In-situ techniques, such as LIF, also allow a direct comparison with other co-located in-situ instruments, improving the understanding of the chemical interactions that occur. Furthermore the size, weight and flexibility of such instruments mean that they are readily deployable on ship and aircraft platforms, as well as at ground-based sites. The University of Leeds LIF-IO instruments have been operational since 2006; data taken at three contrasting locations will be presented. IO measurements were made at the Mace Head Observatory on the west coast of Ireland in 2007. The site is predominantly impacted by background air-masses from the north Atlantic. An anti-correlation between IO concentration and tidal height during the day was observable; a maximum of 33 pptV was observed during the lowest tides. A comparison with concurrent LP-DOAS measurements demonstrates local hot-spots of IO production. The release of I2 from a narrow strip of macro-algae, specifically laminaria, along this coastline acts as the major iodine source. In-situ IO measurements were also made at a second coastal site, in Roscoff, France as part of the Reactive Halogens in the Marine Boundary Layer (RHaMBLe) project. This stretch of coastline is also impacted by macro-algae and high concentrations of IO were again observable at low-tide. In contrast to Mace Head, the Roscoff site was influenced by local pollution. A negative correlation between IO and NO2 was observed during low-tide periods; a positive correlation between IO and new particle bursts was also recorded. This work

  13. Iodine Deficiency

    MedlinePlus

    ... enlargement of the thyroid (goiter – see Goiter brochure ), hypothyroidism (see Hypothyroidism brochure ) and to mental retardation in infants and ... when lying down, and difficulty swallowing and breathing. HYPOTHYROIDISM – As the body’s iodine levels fall, hypothyroidism may ...

  14. Design investigation of solar powered lasers for space applications

    NASA Technical Reports Server (NTRS)

    Taussig, R.; Bruzzone, C.; Quimby, D.; Nelson, L.; Christiansen, W.; Neice, S.; Cassady, P.; Pindroh, A.

    1979-01-01

    The feasibility of solar powered lasers for continuous operation in space power transmission was investigated. Laser power transmission in space over distances of 10 to 100 thousand kilometers appears possible. A variety of lasers was considered, including solar-powered GDLs and EDLs, and solar-pumped lasers. An indirect solar-pumped laser was investigated which uses a solar-heated black body cavity to pump the lasant. Efficiencies in the range of 10 to 20 percent are projected for these indirect optically pumped lasers.

  15. Iodine in diet

    MedlinePlus

    ... good sources are plants grown in iodine-rich soil. Side Effects Lack of enough iodine (deficiency) may occur in places that have iodine-poor soil. Many months of iodine deficiency in a person's ...

  16. Iodine in diet

    MedlinePlus

    ... products also contain iodine. Other good sources are plants grown in iodine-rich soil. ... goiter or hypothyroidism . Without enough iodine, the thyroid ... intake of iodine can reduce the function of the thyroid gland.

  17. The Development and Deployment of a Ground-Based, Laser-Induced Fluorescence Instrument for the In Situ Detection of Iodine Monoxide Radicals

    NASA Technical Reports Server (NTRS)

    Thurlow, M. E.; Co, D. T.; O'Brien, A. S.; Hannun, R. A.; Lapson, L. B.; Hanisco, T. F.; Anderson, J. G.

    2014-01-01

    High abundances of iodine monoxide (IO) are known to exist and to participate in local photochemistry of the marine boundary layer. Of particular interest are the roles IO plays in the formation of new particles in coastal marine environments and in depletion episodes of ozone and mercury in the Arctic polar spring. This paper describes a ground-based instrument that measures IO at mixing ratios less than one part in 1012. The IO radical is measured by detecting laser-induced fluorescence at wavelengths longer that 500 nm. Tunable visible light is used to pump the A23/2 (v = 2) ? X23/2 (v = 0) transition of IO near 445 nm. The laser light is produced by a solid-state, Nd:YAG-pumped Ti:Sapphire laser at 5 kHz repetition rate. The laser-induced fluorescence instrument performs reliably with very high signal-to-noise ratios (>10) achieved in short integration times (<1 min). The observations from a validation deployment to the Shoals Marine Lab on Appledore Island, ME are presented and are broadly consistent with in situ observations from European Coastal Sites. Mixing ratios ranged from the instrumental detection limit (<1 pptv) to 10 pptv. These data represent the first in situ point measurements of IO in North America.

  18. The development and deployment of a ground-based, laser-induced fluorescence instrument for the in situ detection of iodine monoxide radicals

    SciTech Connect

    Thurlow, M. E. Hannun, R. A.; Lapson, L. B.; Anderson, J. G.; Co, D. T.; O'Brien, A. S.; Hanisco, T. F.

    2014-04-15

    High abundances of iodine monoxide (IO) are known to exist and to participate in local photochemistry of the marine boundary layer. Of particular interest are the roles IO plays in the formation of new particles in coastal marine environments and in depletion episodes of ozone and mercury in the Arctic polar spring. This paper describes a ground-based instrument that measures IO at mixing ratios less than one part in 10{sup 12}. The IO radical is measured by detecting laser-induced fluorescence at wavelengths longer that 500 nm. Tunable visible light is used to pump the A{sup 2}Π{sub 3/2} (v{sup ′} = 2) ← X{sup 2}Π{sub 3/2} (v{sup ″} = 0) transition of IO near 445 nm. The laser light is produced by a solid-state, Nd:YAG-pumped Ti:Sapphire laser at 5 kHz repetition rate. The laser-induced fluorescence instrument performs reliably with very high signal-to-noise ratios (>10) achieved in short integration times (<1 min). The observations from a validation deployment to the Shoals Marine Lab on Appledore Island, ME are presented and are broadly consistent with in situ observations from European Coastal Sites. Mixing ratios ranged from the instrumental detection limit (<1 pptv) to 10 pptv. These data represent the first in situ point measurements of IO in North America.

  19. Chemical oxygen-iodine laser (COIL) beam quality predictions using 3D Navier-Stokes (MINT) and wave optics (OCELOT) codes

    NASA Astrophysics Data System (ADS)

    Lampson, Alan I.; Plummer, David N.; Erkkila, John H.; Crowell, Peter G.; Helms, Charles A.

    1998-05-01

    This paper describes a series of analyses using the 3-d MINT Navier-Stokes and OCELOT wave optics codes to calculate beam quality in a COIL laser cavity. To make this analysis tractable, the problem was broken into two contributions to the medium quality; that associated with microscale disturbances primarily from the transverse iodine injectors, and that associated with the macroscale including boundary layers and shock-like effects. Results for both microscale and macroscale medium quality are presented for the baseline layer operating point in terms of single pass wavefront error. These results show that the microscale optical path difference effects are 1D in nature and of low spatial order. The COIL medium quality is shown to be dominated by macroscale effects; primarily pressure waves generated from flow/boundary layer interactions on the cavity shrouds.

  20. Quantum-well lasers for direct solar photopumping

    NASA Technical Reports Server (NTRS)

    Unnikrishnan, Sreenath; Anderson, Neal G.

    1993-01-01

    Semiconductor lasers directly photopumped by focused sunlight may be viable sources of coherent light for intersatellite communications and other low-power spaceborne applications. In this work, we theoretically explore the possibility of realizing such devices. We specifically assess solar pumped operation of separate-confinement-quantum-well heterostructure (SCQWH) lasers based on InGaAs, GaAs, and AlGaA, as fabrication technology for these lasers is mature and they can operate at very low thresholds. We develop a model for step-index single-well SCQWH lasers photopumped by sunlight, examine how threshold solar photoexcitation intensities depend upon material and structure parameters, design optimum structures for solar-pumped operation, and identify design tradeoffs. Our results suggest that laser action should be possible in properly designed structures at readily achievable solar concentrations and that optimum designs for solar-pumped SCQWH lasers differ significantly from those for analogous current injection devices.

  1. Iodine Satellite

    NASA Technical Reports Server (NTRS)

    Kamhawi, Hani; Dankanich, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Iodine Satellite (iSat) spacecraft will be the first CubeSat to demonstrate high change in velocity from a primary propulsion system by using Hall thruster technology and iodine as a propellant. The mission will demonstrate CubeSat maneuverability, including plane change, altitude change and change in its closest approach to Earth to ensure atmospheric reentry in less than 90 days. The mission is planned for launch in fall 2017. Hall thruster technology is a type of electric propulsion. Electric propulsion uses electricity, typically from solar panels, to accelerate the propellant. Electric propulsion can accelerate propellant to 10 times higher velocities than traditional chemical propulsion systems, which significantly increases fuel efficiency. To enable the success of the propulsion subsystem, iSat will also demonstrate power management and thermal control capabilities well beyond the current state-of-the-art for spacecraft of its size. This technology is a viable primary propulsion system that can be used on small satellites ranging from about 22 pounds (10 kilograms) to more than 1,000 pounds (450 kilograms). iSat's fuel efficiency is ten times greater and its propulsion per volume is 100 times greater than current cold-gas systems and three times better than the same system operating on xenon. iSat's iodine propulsion system consists of a 200 watt (W) Hall thruster, a cathode, a tank to store solid iodine, a power processing unit (PPU) and the feed system to supply the iodine. This propulsion system is based on a 200 W Hall thruster developed by Busek Co. Inc., which was previously flown using xenon as the propellant. Several improvements have been made to the original system to include a compact PPU, targeting greater than 80 percent reduction in mass and volume of conventional PPU designs. The cathode technology is planned to enable heaterless cathode conditioning, significantly increasing total system efficiency. The feed system has been designed to

  2. Blackbody-pumped CO2 laser experiment

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Insuik, R. J.

    1983-07-01

    Thermal radiation from a high temperature oven was used as an optical pump to achieve lasing from CO2 mixtures. Laser output as a function of blackbody temperature and gas conditions is described. This achievement represents the first blackbody cavity pumped laser and has potential for solar pumping. Previously announced in STAR as N83-10420

  3. A blackbody radiation-pumped CO2 laser experiment

    NASA Astrophysics Data System (ADS)

    Christiansen, W. H.; Insuik, R. J.; Deyoung, R. J.

    1982-09-01

    Thermal radiation from a high temperature oven was used as an optical pump to achieve lasing from CO2 mixtures. Laser output as a function of blackbody temperature and gas conditions is described. This achievement represents the first blackbody cavity pumped laser and has potential for solar pumping.

  4. Laser welding in space

    NASA Technical Reports Server (NTRS)

    Kaukler, W. F.; Workman, G. L.

    1991-01-01

    Autogenous welds in 304 stainless steel were performed by Nd-YAG laser heating in a simulated space environment. Simulation consists of welding on the NASA KC-135 aircraft to produce the microgravity and by containing the specimen in a vacuum chamber. Experimental results show that the microgravity welds are stronger, harder in the fusion zone, have deeper penetration and have a rougher surface rippling of the weld pool than one-g welds. To perform laser welding in space, a solar-pumped laser concept that significantly increases the laser conversion efficiency and makes welding viable despite the limited power availability of spacecraft is proposed.

  5. Precise modulation of laser radiation by an acousto-optic modulator for stabilisation of the Nd : YAG laser on optical resonances in molecular iodine

    NASA Astrophysics Data System (ADS)

    Denisov, V. I.; Ignatovich, S. M.; Kvashnin, N. L.; Skvortsov, M. N.; Farnosov, S. A.

    2016-05-01

    A system of precise frequency modulation of laser radiation by an acousto-optic modulator, which makes it possible to stabilise the radiation power and simultaneously suppress the residual amplitude modulation to a level of 10-8 of the total laser power at the third harmonic of modulation frequency (~500 Hz), is presented. The use of this system for the Nd : YAG/I2 optical frequency standard and application of digital signal synthesis and processing methods provided a level of frequency standard instability as small as ~10-15 for ~6 × 104 s.

  6. The atmospheric chemistry of iodine monoxide

    SciTech Connect

    Laszlo, B.; Huie, R.E.

    1995-12-01

    The possible role of iodine on tropospheric ozone arid, more recently, stratospheric ozone has been of considerable interest. There have been, however relatively few experimental determination of the chemistry of the important radical, IO. Laser flash photolysis with two-wavelength transient absorption experiments were performed on N{sub 2}O/I{sub 2}+X{sub 2}/N{sub 2} mixtures (X{sub 2} = halogen) at room temperature and total pressure between 8 and 80 kPa. An extended IO absorption spectrum, experimental rate coefficients of IO+IO, IO+O({sup 3}P), IO+BrO, BrO+I and IO+ClO reactions will be presented. Preliminary results show the atmospheric importance of reaction between alkylperoxy radicals and iodine atoms or iodine monoxide radicals. These reactions seem to be important tropospheric iodine sinks.

  7. The {sup 2}P{sub 1/2} {yields} {sup 2}P{sub 3/2} laser transition in atomic iodine and the problem of search for signals from extraterrestrial intelligence

    SciTech Connect

    Kutaev, Yu F; Mankevich, S K; Nosach, O Yu; Orlov, E P

    2007-07-31

    It is proposed to search for signals from extraterrestrial intelligence (ETI) at a wavelength of 1.315 {mu}m of the laser {sup 2}P{sub 1/2} {yields} {sup 2}P{sub 3/2} transition in the atomic iodine, which can be used for this purpose as the natural frequency reference. The search at this wavelength is promising because active quantum filters (AQFs) with the quantum sensitivity limit have been developed for this wavelength, which are capable of receiving laser signals, consisting of only a few photons, against the background of emission from a star under study. In addition, high-power iodine lasers emitting diffraction-limited radiation at 1.315 {mu}m have been created, which highly developed ETI also can have. If a ETI sends in our direction a diffraction-limited 10-ns, 1-kJ laser pulse with the beam diameter of 10 m, a receiver with an AQF mounted on a ten-meter extra-atmospheric optical telescope can detect this signal at a distance of up to 300 light years, irrespective of the ETI position on the celestial sphere. The realisation of the projects for manufacturing optical telescopes of diameter 30 m will increase the research range up to 2700 light years. A weak absorption of the 1.315-{mu}m radiation in the Earth atmosphere (the signal is attenuated by less than 20%) allows the search for ETI signals by using ground telescopes equipped with adaptive optical systems. (laser applications and other topics in quantum electronics)

  8. Iodine-deficiency disorders.

    PubMed

    Zimmermann, Michael B; Jooste, Pieter L; Pandav, Chandrakant S

    2008-10-01

    2 billion individuals worldwide have insufficient iodine intake, with those in south Asia and sub-Saharan Africa particularly affected. Iodine deficiency has many adverse effects on growth and development. These effects are due to inadequate production of thyroid hormone and are termed iodine-deficiency disorders. Iodine deficiency is the most common cause of preventable mental impairment worldwide. Assessment methods include urinary iodine concentration, goitre, newborn thyroid-stimulating hormone, and blood thyroglobulin. In nearly all countries, the best strategy to control iodine deficiency is iodisation of salt, which is one of the most cost-effective ways to contribute to economic and social development. When iodisation of salt is not possible, iodine supplements can be given to susceptible groups. Introduction of iodised salt to regions of chronic iodine-deficiency disorders might transiently increase the proportion of thyroid disorders, but overall the small risks of iodine excess are far outweighed by the substantial risks of iodine deficiency. International efforts to control iodine-deficiency disorders are slowing, and reaching the third of the worldwide population that remains deficient poses major challenges. PMID:18676011

  9. Atomic iodine production in a gas flow by decomposing methyl iodide in a dc glow discharge

    SciTech Connect

    Mikheyev, P A; Shepelenko, A A; Voronov, A I; Kupryaev, Nikolai V

    2002-01-31

    The production of atomic iodine for an oxygen - iodine laser is studied by decomposing methyl iodide in a dc glow discharge in a vortex gas flow. The concentration of iodine atoms in discharge products was measured from the atomic iodine absorption of the radiation of a single-frequency tunable diode laser at a wavelength of 1.315 {mu}m. Atomic iodine concentrations sufficient for the operation of an oxygen - iodine laser were obtained. The concentration of atomic iodine amounted to 3.6 x 10{sup 15} cm{sup -3} for a pressure of the carrying argon gas of 15 Torr. The discharge stabilisation by a vortex gas flow allowed the glow discharge to be sustained in a strongly electronegative halogen-containing gas mixture for pressures up to 20 Torr. (active media)

  10. Characterization of low-molecular weight iodine-terminated polyethylenes by gas chromatography/mass spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry with the use of derivatization.

    PubMed

    Zaikin, Vladimir G; Borisov, Roman S; Polovkov, Nikolai Yu; Zhilyaev, Dmitry I; Vinogradov, Aleksei A; Ivanyuk, Aleksei V

    2013-01-01

    Gas chromatography/mass spectrometry (GC/MS) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry, in conjunction with various derivatization approaches, have been applied to structure determination of individual oligomers and molecular-mass distributions (MMD) in low-molecular mass polyethylene having an iodine terminus. Direct GC/MS analysis has shown that the samples under investigation composed of polyethyelene-iodides (major components) and n-alkanes. Exchange reaction with methanol in the presence of NaOH gave rise to methoxy-derivatives and n-alkenes. Electron ionization mass spectra have shown that the former contained terminal methoxy groups indicating the terminal position of the iodine atom in the initial oligomers. MMD parameters have been determined with the aid of MALDI mass spectrometry followed by preliminary derivatization-formation of covalently bonded charge through the reaction of iodides with triphenylphosphine, trialkylamines, pyridine or quinoline. The mass spectra revealed well-resolved peaks for cationic parts of derivatized oligomers allowing the determination of MMD. The latter values have been compared with those calculated from GC/MS data. PMID:24308197

  11. Iodine deficiency disorders.

    PubMed

    Elliott, T C

    1987-01-01

    Iodine deficiency disorder (IDD) affects 800 million people in the world, yet iodine supplementation is one of the most cost-effective nutritional interventions known. Iodine is incorporated into thyroid hormones, necessary for regulating metabolic rate, growth, and development of the brain and nervous system. IDD may appear as goiter in adults, usually not a serious problem, or in cretinism in children, which is marked by severe mental and physical retardation, with irreversible hearing and speech defects and either deaf-mutism, squint and paralysis, or stunting and edema. Children supplemented by age 1 or 2 can sometimes be helped. Foods contain variable amounts of iodine dependent on the soil where they are grown, hence mountainous and some inland regions have high goiter and IDD incidence. There are also goitrogenic foods, typically those of the cabbage family. Diagnosis is clinical or by blood tests for thyroid hormone levels and ratios. Finger-stick methods are available. Prevention of IDD is simple with either iodized salt or flour, iodinated central water supplies, injectable or oral iodine-containing oil. All cost about $.04 per person per year, except injections, which cost about $1 per person, but have the advantage that they could be combined with immunizations. Local problems with supplements are loss of iodine in salt with storage in tropics, and local production of cheaper uniodinated salt. Emphasis should be given to pregnant women and young children. There is no harm in giving pregnant women iodine injections in 2nd or 3rd trimester. PMID:12343033

  12. Effect of vibrationally excited I{sub 2}(a{sup 1{Delta}}{sub g}) molecules on the parameters of the active medium of an oxygen - iodine laser

    SciTech Connect

    Azyazov, V N; Antonov, I O; Pichugin, S Yu; Ufimtsev, N I

    2004-12-31

    A comparison of the experimental and theoretical results shows that quenching of one singlet oxygen molecule leads to the formation of 4.5 vibrational quanta of the I{sub 2} molecule on the average in the active medium of an oxygen-iodine laser. The dependence of threshold yield of singlet oxygen and of the gain on the relative concentration of vibrationally excited I{sub 2}(a{sup 1{Delta}}{sub g}) molecules are studied. The threshold yield of singlet oxygen increases with the relative concentration of vibrationally excited I{sub 2} molecules and may be several percent higher than the value assumed earlier. The gain depends weakly on the relative concentration of vibrationally excited oxygen molecules. (active media)

  13. Iodine generator for reclaimed water purification

    NASA Technical Reports Server (NTRS)

    Wynveen, R. A.; Powell, J. D.; Schubert, F. H. (Inventor)

    1977-01-01

    The system disclosed is for controlling the iodine level in a water supply in a spacecraft. It includes an iodine accumulator which stores crystalline iodine, an electrochemical valve to control the input of iodine to the drinking water and an iodine dispenser. A pump dispenses fluid through the iodine dispenser and an iodine sensor to a potable water tank storage. The iodine sensor electronically detects the iodine level in the water, and through electronic means, produces a correction current control. The correction current control operates the electro-chemical iodine valve to release iodine from the iodine accumulator into the iodine dispenser.

  14. Lasers '85; Proceedings of the Eighth International Conference, Las Vegas, NV, Dec. 2-6, 1985

    SciTech Connect

    Wang, C.P.

    1986-01-01

    The present conference on laser technology development encompasses issues in such areas as VUV and X-ray lasers; optical phase conjugation and nonlinear optics; laser applications in medicine; methods for optical processing; laser and nonlinear spectroscopy; ultrashort-pulse lasers and their applications; frequency selection in pulsed lasers; and interactions between laser beams, material surfaces, and material volumes. Also treated are laser applications in the Strategic Defense Initiative program, chemical laser design and performance, the lasing of biophysical materials, laser diagnostics in fluids and plasma, semiconductor laser diodes and arrays, solid state lasers, radiation- and solar-pumped lasers, laser cavities and propagation, remote sensing with lasers and fiber-optics, coupled resonators and diode lasers, industrial applications of lasers, excimer lasers, optoelectronics, CO/sub 2/ lasers, fiber-optic sensors, alexandrite lasers, free electron lasers, and IR and visible wavelength lasers.

  15. Laser satellite power systems

    SciTech Connect

    Walbridge, E.W.

    1980-01-01

    A laser satellite power system (SPS) converts solar power captured by earth-orbiting satellites into electrical power on the earth's surface, the satellite-to-ground transmission of power being effected by laser beam. The laser SPS may be an alternative to the microwave SPS. Microwaves easily penetrate clouds while laser radiation does not. Although there is this major disadvantage to a laser SPS, that system has four important advantages over the microwave alternative: (1) land requirements are much less, (2) radiation levels are low outside the laser ground stations, (3) laser beam sidelobes are not expected to interfere with electromagnetic systems, and (4) the laser system lends itself to small-scale demonstration. After describing lasers and how they work, the report discusses the five lasers that are candidates for application in a laser SPS: electric discharge lasers, direct and indirect solar pumped lasers, free electron lasers, and closed-cycle chemical lasers. The Lockheed laser SPS is examined in some detail. To determine whether a laser SPS will be worthy of future deployment, its capabilities need to be better understood and its attractiveness relative to other electric power options better assessed. First priority should be given to potential program stoppers, e.g., beam attenuation by clouds. If investigation shows these potential program stoppers to be resolvable, further research should investigate lasers that are particularly promising for SPS application.

  16. Radioactive iodine uptake

    MedlinePlus

    ... the testing center so that the amount of radioactivity in the thyroid gland can be measured. This ... The amount of radioactivity is very small, and there have been no documented side effects. The amount of iodine used is less than ...

  17. Iodine Clock Reaction.

    ERIC Educational Resources Information Center

    Mitchell, Richard S.

    1996-01-01

    Describes a combination of solutions that can be used in the study of kinetics using the iodine clock reaction. The combination slows down degradation of the prepared solutions and can be used successfully for several weeks. (JRH)

  18. Radioactive iodine uptake

    MedlinePlus

    ... uptake may be due to: Factitious hyperthyroidism Iodine overload Subacute thyroiditis Silent (or painless) thyroiditis Amiodarone Risks ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  19. Iodine Hall Thruster

    NASA Technical Reports Server (NTRS)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  20. Spaceborne Photonics Institute

    NASA Technical Reports Server (NTRS)

    Venable, D. D.; Farrukh, U. O.; Han, K. S.; Hwang, I. H.; Jalufka, N. W.; Lowe, C. W.; Tabibi, B. M.; Lee, C. J.; Lyons, D.; Maclin, A.

    1994-01-01

    This report describes in chronological detail the development of the Spaceborne Photonics Institute as a sustained research effort at Hampton University in the area of optical physics. This provided the research expertise to initiate a PhD program in Physics. Research was carried out in the areas of: (1) modelling of spaceborne solid state laser systems; (2) amplified spontaneous emission in solar pumped iodine lasers; (3) closely simulated AM0 CW solar pumped iodine laser and repeatedly short pulsed iodine laser oscillator; (4) a materials spectroscopy and growth program; and (5) laser induced fluorescence and atomic and molecular spectroscopy.

  1. Dither Cavity Length Controller with Iodine Locking

    NASA Astrophysics Data System (ADS)

    Lawson, Marty; Eloranta, Ed

    2016-06-01

    A cavity length controller for a seeded Q-switched frequency doubled Nd:YAG laser is constructed. The cavity length controller uses a piezo-mirror dither voltage to find the optimum length for the seeded cavity. The piezo-mirror dither also dithers the optical frequency of the output pulse. [1]. This dither in optical frequency is then used to lock to an Iodine absorption line.

  2. Deep well solar pump

    SciTech Connect

    Vanek, J.

    1990-02-06

    This patent describes, in a pump having a source of gas under pressure, and a gas operated pump, a mechanism periodically injecting gas from the source of gas into the gas operated pump. It comprises: a long period pendulum turning towards a first position by gravity, an injection valve connected between the source of gas under pressure and the gas operated pump, a linkage between the pendulum and the injection valve. The linkage opening the injection valve when the pendulum is in the first position, an impulse tube connected between the injection valve and the gas operated pump, a member having a surface adjacent to the first position of the pendulum, and an elastic impulse bladder connected to the impulse tube adjacent to the surface so that inflation of the impulse bladder on the opening of the injection valve forces the impulse bladder against the pendulum urging the pendulum against the force of gravity toward a second position.

  3. HWVP Iodine Trap Evaluation

    SciTech Connect

    Burger, Leland L.; Scheele, Randall D.

    2004-09-24

    This report details our assessment of the chemistry of the planned Hanford Waste Vitrification Plant (HWVP) off-gas system and its impact on the applicability of known iodine removal and control methods. To predict the gaseous species in the off-gas system, we completed thermodynamic calculations to determine theoretical equilibrium concentrations of the various potential chemical species. In addition, we found that HWVP pilot-plant experiments were generally consistent with the known chemistry of the individual elements present in the off gas. Of the known trapping techniques for radioiodine, caustic scrubbing and silver-containing sorbents are, in our opinion, the most attractive methods to reduce the iodine concentration in the HWVP melter off gas (MOG) after it has passed through the high-efficiency particulate air (HEPA) filter. These two methods were selected because they (1) have demonstrated retention factors (RFs), ratio of amount in and amount out, of 10 to 1000, which would be sufficient to reduce the iodine concentration in the MOG to below regulatory limits; (2) are simple to apply; (3) are resistant to oxidizing gases such as NOx; (4) do not employ highly hazardous or highly corrosive agents; (5) require containment vessels constructed or common materials; (6) have received extensive laboratory development; (7) and the radioactive wastes produced should be easy to handle. On the basis of iodine trapping efficiency, simplicity of operation, and waste management, silver sorbents are superior to caustic scrubbing, and, or these sorbents, we prefer the silver zeolites. No method has been fully demonstrated, from laboratory-scale through pilot-plant testing, to be an effective iodine trap at the low iodine concentration (2 x 10-11 mol I/L) expected in the MOG of the HWVP in the presence of the other gaseous off gas components. In terms of compatibility of the trapping technology with the components in the MOG, there is some question about the resistance of

  4. Iodine deficiency disorders in Europe.

    PubMed Central

    Delange, F.; Bürgi, H.

    1989-01-01

    Recent data on iodine excretion in the urine of adults, adolescents and newborns and on the iodine content of breast milk indicate a high prevalence of iodine deficiency (moderate in many cases and severe in a few) in many European countries. These cases may manifest as subclinical hypothyroidism in neonates and as goitre in adolescents and adults. Lack of iodine causes not only goitre, but also mental deficiency, hearing loss and other neurological impairments, and short stature due to thyroid insufficiency during fetal development and childhood. Although iodinated salt is available theoretically in most countries where it is needed, its quality and share of the market are often unsatisfactory. In many countries where only household salt is iodinated the iodine content has been set too low owing to an overestimation of household salt consumption. Governments are therefore urged to pass legislation and provide means for efficient iodination of salt wherever this is necessary. PMID:2670299

  5. Laser satellite power systems - Concepts and issues

    NASA Astrophysics Data System (ADS)

    Walbridge, E. W.

    A laser satellite power system (SPS) converts solar power captured by Earth-orbiting satellites into electrical power on the Earth's surface, the satellite-to-ground transmission of power being effected by a laser beam. The laser SPS is an alternative to the microwave SPS. Lasers and how they work are described, as are the types of lasers - electric discharge, direct and indirect solar pumped, free electron, and closed-cycle chemical - that are candidates for application in a laser SPS. The advantages of a laser SPS over the microwave alternative are pointed out. One such advantage is that, for the same power delivered to the utility busbar, land requirements for a laser system are much smaller (by a factor of 21) than those for a microwave system. The four laser SPS concepts that have been presented in the literature are described and commented on. Finally key issues for further laser SPS research are discussed.

  6. Effect of dietary iodine on production of iodine enriched eggs

    PubMed Central

    Sumaiya, Shaikh; Nayak, Sunil; Baghel, R. P. S.; Nayak, Anju; Malapure, C. D.; Kumar, Rajesh

    2016-01-01

    Aim: Objective of this study was to investigate the effect of different levels of iodine supplementation on iodine content of eggs in laying hens. Materials and Methods: In the experiment, 135 laying hens (White Leghorn) of 55 weeks age were randomly distributed to 5 dietary treatments; each group contained 27 laying hens distributed in three replicates of 9 birds each. Diet T1 was control basal layer diet without iodine enrichment in which iodine content (I2) was as per NRC recommendation. Basal diets were supplemented with calcium iodate (Ca (IO3)2) at 5, 10, 15 and 20 mg/kg in T2, T3, T4 and T5 groups, respectively. The iodine content in the calcium iodate is 65.21%, therefore, the diets T2, T3, T4 and T5 contained 3.25, 6.50, 9.75 and 13.0 ppm iodine, respectively. The laying hens were fed the respective experimental diets ad libitum during the experimental period of 10-week. The iodine content of egg yolk and albumen was analyzed at the end of 5th and 10th week of the experiment. Economics of feeding for the production of iodine enriched egg was calculated at the end of the experiment. Results: Increasing iodine levels in diet of hens from 0.45 to 13.0 ppm significantly increased egg iodine concentration, the highest concentration of egg iodine was observed in the group fed diet supplemented with 13.0 ppm iodine followed by those fed 9.75, 6.50, 3.25 and 0.45 ppm iodine in diet. There was no significant difference in the iodine levels of unboiled versus boiled eggs. Therefore, the consumers are ensured to receive the optimal levels of iodine from boiled iodine-enriched eggs. Among different diets, minimum and significantly lower feeding cost (Rs. per dozen or per kg eggs) was noticed in hens allotted T3 diet (6.50 ppm I2). However, feeding cost of hens receiving 3.25 and 9.25 ppm I2 was statistically (p<0.05) similar to control group (T1). Further, it was noticed that feeding cost (Rs. per dozen or per kg eggs) was significantly increased due to the inclusion

  7. Lasers.

    ERIC Educational Resources Information Center

    Schewe, Phillip F.

    1981-01-01

    Examines the nature of laser light. Topics include: (1) production and characteristics of laser light; (2) nine types of lasers; (3) five laser techniques including holography; (4) laser spectroscopy; and (5) laser fusion and other applications. (SK)

  8. [Improving the human iodine supply by iodination of swine feed].

    PubMed

    Rambeck, W A; Kaufmann, S; Feng, J; Hollwich, W; Arnold, R

    1997-07-01

    Germany and several other countries are areas of severe iodine deficiency. In addition to iodized salt additional strategies to fight iodine deficiency exist. A promising possibility is the supplementation of feed with iodine, in order to increase its content in food of animal origin. In a feeding experiment 24 male castrated and female piglets of the cross breed Deutsche Landrasse x Pietrain were fed a high iodine supplemented diet. At a body weight of 100 kg the animals were slaughtered and the effect of the iodine supplementation on iodine content in the organs was studied. Animals receiving 30 mg iodine/kg feed showed significantly higher iodine contents in muscle, heart, kidney, liver, serum, fat and in the thyroidea than animals receiving no iodine supplementation. The iodine content in muscle and organs increased by a factor three to seven. Concerning meat quality and other slaughter parameters there was no difference between the two groups. This demonstrates that this strategy is in addition to iodized salt a possibility to reduce iodine deficiency. PMID:9312888

  9. Iodine: deficiency and therapeutic considerations.

    PubMed

    Patrick, Lyn

    2008-06-01

    Iodine deficiency is generally recognized as the most commonly preventable cause of mental retardation and the most common cause of endocrinopathy (goiter and primary hypothyroidism). Iodine deficiency becomes particularly critical in pregnancy due to the consequences for neurological damage during fetal development as well as during lactation. The safety of therapeutic doses of iodine above the established safe upper limit of 1 mg is evident in the lack of toxicity in the Japanese population that consumes 25 times the median intake of iodine consumption in the United States. Japan's population suffers no demonstrable increased incidence of autoimmune thyroiditis or hypothyroidism. Studies using 3.0- to 6.0-mg doses to effectively treat fibrocystic breast disease may reveal an important role for iodine in maintaining normal breast tissue architecture and function. Iodine may also have important antioxidant functions in breast tissue and other tissues that concentrate iodine via the sodium iodide symporter. PMID:18590348

  10. Adsorption of iodine from COIL waste gas on soaked coal-based activated carbon

    NASA Astrophysics Data System (ADS)

    Zhou, Junbo; Hao, Shan; Gao, Liping

    2014-04-01

    The chemical oxygen-iodine laser (COIL) has wide application prospects in military, industrial and medical treatment fields as a second generation gas chemical laser to follow the first HF/DF chemical laser. However, a COIL releases large amounts of gas, such as helium, oxygen, chlorine and iodine. Chlorides have a serious corrosive effect on the system, especially iodine vapor crystallization, which seriously endangers the normal use of vacuum systems, and radioactive methyl iodide, which is hazardous to operators and pollutes the environment. The use of soaked coal-based activated carbon as an adsorbent for removing methyl iodine is proposed, while it is proposed that coal-based activated carbon is an effective adsorbent for removing stable iodine. The research conducted in this work shows that iodine residues are less than 0.5 μg ml-1 after the adsorption treatment and the decontamination factor of the coal-based activated carbon for removing stable iodine is more than 1000. Using this method can achieve the purpose of removing harmful iodine, satisfy the requirements for engineering applications, and also be applied to other nuclear power plant flue gas treatments.

  11. [Allergy to iodinated drugs and to foods rich in iodine: Iodine is not the allergenic determinant].

    PubMed

    Dewachter, Pascale; Mouton-Faivre, Claudie

    2015-11-01

    "Iodine allergy" does not exist. The concept of "iodine allergy" should be abandoned since it may result in inappropriate measures such as drug, food or environmental eviction. Immediate or non-immediate allergic hypersensitivity to iodinated contrast media is not infrequent. The corresponding allergens have not been identified. Iodine is not involved. Immediate or non-immediate allergic hypersensitivity to povidone iodine is rare. The corresponding allergen is povidone in case of immediate hypersensitivity while nonoxynol might be involved during non-immediate hypersensitivity. Seafood allergens belong to a group of muscle proteins. Immediate drug hypersensitivity or food hypersensitivity is assessed by immediate-reading skin tests while non-immediate drug hypersensitivity is investigated by delayed-reading skin testing. Combined histamine and tryptase measurement is invaluable during the diagnostic approach of immediate hypersensitivity. Other biological tests are being evaluated. Allergic hypersensitivity to iodinated contrast agents does not contraindicate the use of other iodinated drugs. PMID:26387623

  12. Iodine supplementation: benefits outweigh risks.

    PubMed

    Delange, F; Lecomte, P

    2000-02-01

    In 1990, iodine deficiency affected almost one-third of the world population and was the greatest single cause of preventable brain damage and mental retardation. Following a resolution adopted by the World Summit for Children in 1990. major programmes of iodine supplementation were implemented by the governments of the affected countries with the support of major donors. Iodisation of salt was recognised as the method of choice. Nine years later, by April 1999, 75% of the affected countries had legislation on salt iodisation and 68% of the affected populations had access to iodised salt. The prevalence of iodine deficiency disorders decreased drastically in most countries and the deficiency disappeared completely in some such as Peru. This result constitutes a public heath success unprecedented with a non-infectious disease. However, occasional adverse effects occurred. The principle effect is iodine-induced hyperthyroidism which occurs essentially in older people with autonomous nodular goitres, especially following iodine intake that is too rapid and of too massive an increment. The incidence of the disorder is usually low and reverts spontaneously to the background rate of hyperthyroidism or even below this rate after 1 to 10 years of iodine supplementation. The possible occurrence of iodine-induced thyroiditis in susceptible individuals has not been clearly demonstrated by large epidemiological surveys. Iodine supplementation is followed by an increased prevalence of occult papillary carcinoma of the thyroid discovered at autopsy but the prognosis of thyroid cancer is improved due to a shift towards differentiated forms of thyroid cancer that are diagnosed at earlier stages. Iodine-induced hyperthyroidism and other adverse effects can be almost entirely avoided by adequate and sustained quality control and monitoring of iodine supplementation which should also confirm adequate iodine intake. Available evidence clearly confirms that the benefits of correcting

  13. High-performance iodine fiber frequency standard.

    PubMed

    Lurie, Anna; Baynes, Fred N; Anstie, James D; Light, Philip S; Benabid, Fetah; Stace, Thomas M; Luiten, Andre N

    2011-12-15

    We have constructed a compact and robust optical frequency standard based around iodine vapor loaded into the core of a hollow-core photonic crystal fiber (HC-PCF). A 532 nm laser was frequency locked to one hyperfine component of the R(56) 32-0 (127)I(2) transition using modulation transfer spectroscopy. The stabilized laser demonstrated a frequency stability of 2.3×10(-12) at 1 s, almost an order of magnitude better than previously reported for a laser stabilized to a gas-filled HC-PCF. This limit is set by the shot noise in the detection system. We present a discussion of the current limitations to the performance and a route to improve the performance by more than an order of magnitude. PMID:22179880

  14. An iodine hypersonic wind tunnel for the study of nonequilibrium reacting flows

    NASA Technical Reports Server (NTRS)

    Pham-Van-diep, G. C.; Muntz, E. P.; Weaver, D. P.; Dewitt, T. G.; Bradley, M. K.; Erwin, D. A.; Kunc, J. A.

    1992-01-01

    A pilot scale hypersonic wind tunnel operating on pure iodine vapor has been designed and tested. The wind tunnel operates intermittently with a run phase lasting approximately 20 minutes. Successful recirculation of the iodine used during the run phase has been achieved but can be improved. Relevant issues regarding the full scale facility's design and operation, and the use of iodine as a working gas are discussed. Continuous wave laser induced fluorescence was used to monitor number densities within the plume flowfield, while pulsed laser induced fluorescence was used in an initial attempt to measure vibrational energy state population distributions. Preliminary nozzle flow calculations based on finite rate chemistry are presented.

  15. Iodine addition using triiodide solutions

    NASA Technical Reports Server (NTRS)

    Rutz, Jeffrey A.; Muckle, Susan V.; Sauer, Richard L.

    1992-01-01

    The study develops: a triiodide solution for use in preparing ground service equipment (GSE) water for Shuttle support, an iodine dissolution method that is reliable and requires minimal time and effort to prepare, and an iodine dissolution agent with a minimal concentration of sodium salt. Sodium iodide and hydriodic acid were both found to dissolve iodine to attain the desired GSE iodine concentrations of 7.5 +/- 2.5 mg/L and 25 +/- 5 mg/L. The 1.75:1 and 2:1 sodium iodide solutions produced higher iodine recoveries than the 1.2:1 hydriodic acid solution. A two-hour preparation time is required for the three sodium iodide solutions. The 1.2:1 hydriodic acid solution can be prepared in less than 5 min. Two sodium iodide stock solutions (2.5:1 and 2:1) were found to dissolve iodine without undergoing precipitation.

  16. Hermetic optical-fiber iodine frequency standard.

    PubMed

    Light, Philip S; Anstie, James D; Benabid, Fetah; Luiten, Andre N

    2015-06-15

    We have built an optical-frequency standard based on interrogating iodine vapor that has been trapped within the hollow core of a hermetically sealed kagome-lattice photonic crystal fiber. A frequency-doubled Nd:YAG laser locked to a hyperfine component of the P(142)37-0 I2127 transition using modulation transfer spectroscopy shows a frequency stability of 3×10(-11) at 100 s. We discuss the impediments in integrating this all-fiber standard into a fully optical-fiber-based system, and suggest approaches that could improve performance of the frequency standard substantially. PMID:26076241

  17. Iodine neutron capture therapy

    NASA Astrophysics Data System (ADS)

    Ahmed, Kazi Fariduddin

    A new technique, Iodine Neutron Capture Therapy (INCT) is proposed to treat hyperthyroidism in people. Present thyroid therapies, surgical removal and 131I treatment, result in hypothyroidism and, for 131I, involve protracted treatment times and excessive whole-body radiation doses. The new technique involves using a low energy neutron beam to convert a fraction of the natural iodine stored in the thyroid to radioactive 128I, which has a 24-minute half-life and decays by emitting 2.12-MeV beta particles. The beta particles are absorbed in and damage some thyroid tissue cells and consequently reduce the production and release of thyroid hormones to the blood stream. Treatment times and whole-body radiation doses are thus reduced substantially. This dissertation addresses the first of the several steps needed to obtain medical profession acceptance and regulatory approval to implement this therapy. As with other such programs, initial feasibility is established by performing experiments on suitable small mammals. Laboratory rats were used and their thyroids were exposed to the beta particles coming from small encapsulated amounts of 128I. Masses of 89.0 mg reagent-grade elemental iodine crystals have been activated in the ISU AGN-201 reactor to provide 0.033 mBq of 128I. This activity delivers 0.2 Gy to the thyroid gland of 300-g male rats having fresh thyroid tissue masses of ˜20 mg. Larger iodine masses are used to provide greater doses. The activated iodine is encapsulated to form a thin (0.16 cm 2/mg) patch that is then applied directly to the surgically exposed thyroid of an anesthetized rat. Direct neutron irradiation of a rat's thyroid was not possible due to its small size. Direct in-vivo exposure of the thyroid of the rat to the emitted radiation from 128I is allowed to continue for 2.5 hours (6 half-lives). Pre- and post-exposure blood samples are taken to quantify thyroid hormone levels. The serum T4 concentration is measured by radioimmunoassay at

  18. Health consequences of iodine deficiency.

    PubMed

    Kapil, Umesh

    2007-12-01

    Iodine Deficiency Disorders (IDD) are one of the biggest worldwide public health problem of today. Their effect is hidden and profoundly affects the quality of human life. Iodine deficiency occurs when the soil is poor in iodine, causing a low concentration in food products and insufficient iodine intake in the population. When iodine requirements are not met, the thyroid may no longer be able to synthesize sufficient amounts of thyroid hormone. The resulting low-level of thyroid hormones in the blood is the principal factor responsible for the series of functional and developmental abnormalities, collectively referred to as IDD. Iodine deficiency is a significant cause of mental developmental problems in children, including implications on reproductive functions and lowering of IQ levels in school-aged children. The consequence of iodine deficiency during pregnancy is impaired synthesis of thyroid hormones by the mother and the foetus. An insufficient supply of thyroid hormones to the developing brain may result in mental retardation. Brain damage and irreversible mental retardation are the most important disorders induced by iodine deficiency. Daily consumption of salt fortified with iodine is a proven effective strategy for prevention of IDD. PMID:21748117

  19. Iodine-Catalyzed Polysaccharide Esterification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A review is provided of the recent reports to use iodine-catalyzed esterification reaction to produce esters from polysaccharides. The process entails reaction of the polysaccharide with an acid anhydride in the presence of a catalytic level of iodine, and in the absence of additional solvents. T...

  20. Hypothyroidism following iodine-131 therapy

    SciTech Connect

    Hays, M.T.

    1982-02-01

    A teaching editorial dealing with the hypothyroidism side effect of Iodine-131 radiotherapy is presented. The author reviews two articles in this issue of the Journal of Nuclear Medicine on the subject, discusses Graves' disease, Iodine 125 radiotherapy, and the patient-physician relationship when dealing with the problem. (JMT)

  1. Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency.

    PubMed

    Ares, S; Quero, J; Durán, S; Presas, M J; Herruzo, R; Morreale de Escobar, G

    1994-11-01

    As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine--mean (SEM) 10 (1) microgram/dl--than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30 weeks' gestational age took 3.1 (1.1) micrograms/day at 5 days of age and 29.8 (2.7) micrograms by 2 months of age. This problem is not exclusive to Spanish premature babies as the iodine content of many of the formulas on sale in other countries was also inadequate. It is concluded that preterm infants who are formula fed are at high risk of iodine deficiency. PMID:7820714

  2. Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency.

    PubMed Central

    Ares, S; Quero, J; Durán, S; Presas, M J; Herruzo, R; Morreale de Escobar, G

    1994-01-01

    As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine--mean (SEM) 10 (1) microgram/dl--than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30 weeks' gestational age took 3.1 (1.1) micrograms/day at 5 days of age and 29.8 (2.7) micrograms by 2 months of age. This problem is not exclusive to Spanish premature babies as the iodine content of many of the formulas on sale in other countries was also inadequate. It is concluded that preterm infants who are formula fed are at high risk of iodine deficiency. PMID:7820714

  3. Criteria for the evaluation of laser solar energy converter systems

    NASA Technical Reports Server (NTRS)

    Harries, W. L.

    1985-01-01

    Assuming that a parabolic insolation-collection mirror-based solar pumped laser has a collector and heat emitter whose weights are proportional to their areas, and that the weight of the laser is negligible by comparison, the output power/unit weight can be expressed in terms of the efficiencies and working temperatures of the system. This ratio appears to be several times higher for an IBr laser than for one operating on C3F7I, because the solar utilization efficiency is greater for the former despite its lower working temperature.

  4. COIL power extraction enhanced by reducing/eliminating iodine clusters in a high Mach number nitrogen mixing nozzle

    NASA Astrophysics Data System (ADS)

    Marshall, J.; Healey, K.; Croker, B.; Kendrick, K.; Yang, T. T.; Hsia, Y. C.; Dickerson, R. A.; Forman, L.

    2006-02-01

    Heterogeneous iodine cluster formation has been identified as the responsible factor resulting in large iodine titration requirements for Boeing's first high Mach number nitrogen ejector nozzle. A solution employing geometrically produced aerodynamic heating in the flow was envisioned to break up these clusters. Horizontal and vertical wire arrays (cluster busters) placed downstream of the nozzle exit plane (NEP) have been shown to significantly reduce the optimal iodine titration and to greatly improve the power extraction efficiency of the Chemical Oxygen-Iodine Laser utilizing this first generation ejector nozzle.

  5. Iodine deficiency disorders in Bangladesh.

    PubMed

    Yusuf, H K; Quazi, S; Kahn, M R; Mohiduzzaman, M; Nahar, B; Rahman, M M; Islam, M N; Khan, M A; Shahidullah, M; Hoque, T; Baquer, M; Pandav, C S

    1996-01-01

    An extensive iodine deficiency disorders survey was conducted in Bangladesh in 1993 to assess the latest iodine nutriture status of the country. The clinical variables of the survey were goitre and cretinism, and the biochemical variable was urinary iodine. The "EPI-30 cluster" sampling methodology was followed for selecting the survey sites. In each survey site, the study population consisted of boys and girls, aged 5-11 years, and men and women, aged 15-44 years, in about equal populations. The total number of survey sites was 78 and the total number of respondents was 30,072. The total number of urine samples was 4512 (15% sub-sample). The current total goitre rate (grade 1 + grade 2) in Bangladesh is 47.1% (hilly, 44.4%; flood-prone, 50.7%; and plains, 45.6%). The prevalence of cretinism in the country is 0.5% (hilly, 0.8%; flood-prone, 0.5%; and plains, 0.3%). Nearly 69% of Bangladeshi population have biochemical iodine deficiency (urinary iodine excretion [UIE] < 10 mg/dl) (hilly, 84.4; flood-prone, 67.1%; and plains 60.4%). Women and children are more affected that men, in terms of both goitre prevalence and UIE. The widespread severe iodine deficiency in all ecological zones indicates that the country as a whole is an iodine-deficient region. Important recommendations of global interest are made from the experience of the survey. PMID:10829973

  6. Iodine Tagging Velocimetry in a Mach 10 Wake

    NASA Technical Reports Server (NTRS)

    Balla, Robert Jeffrey

    2013-01-01

    A variation on molecular tagging velocimetry (MTV) [1] designated iodine tagging velocimetry (ITV) is demonstrated. Molecular iodine is tagged by two-photon absorption using an Argon Fluoride (ArF) excimer laser. A single camera measures fluid displacement using atomic iodine emission at 206 nm. Two examples ofMTVfor cold-flowmeasurements areN2OMTV [2] and Femtosecond Laser Electronic Excitation Tagging [3]. These, like most MTV methods, are designed for atmospheric pressure applications. Neither can be implemented at the low pressures (0.1- 1 Torr) in typical hypersonic wakes. Of all the single-laser/singlecamera MTV approaches, only Nitric-Oxide Planar Laser Induced Fluorescence-based MTV [4] has been successfully demonstrated in a Mach 10 wake. Oxygen quenching limits transit times to 500 ns and accuracy to typically 30%. The present note describes the photophysics of the ITV method. Off-body velocimetry along a line is demonstrated in the aerothermodynamically important and experimentally challenging region of a hypersonic low-pressure near-wake in a Mach 10 air wind tunnel. Transit times up to 10 µs are demonstrated with conservative errors of 10%.

  7. Understanding Hotspots of Iodine Chemistry: Comparison of Spatially-averaged and Point Measurements of Iodine Monoxide

    NASA Astrophysics Data System (ADS)

    Commane, R.; Bale, C. S. E.; Ingham, T.; Heard, D. E.; Bloss, W. J.; Seitz, K.; Platt, U.

    2009-04-01

    The iodine monoxide (IO) radical plays an important role in marine boundary layer chemistry. IO catalytically destroys ozone, affects HOx and NOx partitioning and has been implicated as a precursor to new particle formation. IO is formed by the reaction of ozone with iodine atoms generated by the photolysis of molecular iodine and photo-labile iodocarbons. Measurements of IO were made at the Mace Head Atmospheric Research Station (MHARS) in August 2007 using two different methods. Point measurements of IO were made using a portable laser-induced fluorescence (LIF) instrument. The measurement point was located 50 m from a narrow intertidal region, with macroalgae exposed only at some low tides. A long-path differential optical absorption spectroscopy (LP-DOAS) instrument measured IO concentrations over a large spatial scale from the point measurement site (14 km total path length), including measurements across intertidal regions containing macro-algae. High time-resolution (10 s) data from the LIF instrument shows significant variability in IO mixing ratios at low tide (± 20 pptv over 1 minute). LIF point measurements of IO peaked at 33.8 pptv (10 s integration time) at daytime low tide (the highest mixing ratios of IO measured worldwide), while DOAS spatially-averaged measurements of IO peaked at 4.4 pptv (10 minute integration time) over the same period. Data from the two instruments are compared with tidal variations and the relationship between point and spatially-averaged measurements is analysed.

  8. Research needs for assessing iodine intake, iodine status, and the effects of maternal iodine supplementation.

    PubMed

    Ershow, Abby G; Goodman, Gay; Coates, Paul M; Swanson, Christine A

    2016-09-01

    The Office of Dietary Supplements of the NIH convened 3 workshops on iodine nutrition in Rockville, Maryland, in 2014. The purpose of the current article is to summarize and briefly discuss a list of research and resource needs developed with the input of workshop participants. This list is composed of the basic, clinical, translational, and population studies required for characterizing the benefits and risks of iodine supplementation, along with related data, analyses, evaluations, methods development, and supporting activities. Ancillary studies designed to use the participant, biological sample, and data resources of ongoing and completed studies (including those not originally concerned with iodine) may provide an efficient, cost-effective means to address some of these research and resource needs. In the United States, the foremost question is whether neurobehavioral development in the offspring of mildly to moderately iodine-deficient women is improved by maternal iodine supplementation during pregnancy. It is important to identify the benefits and risks of iodine supplementation in all population subgroups so that supplementation can be targeted, if necessary, to avoid increasing the risk of thyroid dysfunction and related adverse health effects in those with high iodine intakes. Ultimately, there will be a need for well-designed trials and other studies to assess the impact of maternal supplementation on neurodevelopmental outcomes in the offspring. However, 2 basic information gaps loom ahead of such a study: the development of robust, valid, and convenient biomarkers of individual iodine status and the identification of infant and toddler neurobehavioral development endpoints that are sensitive to mild maternal iodine deficiency during pregnancy and its reversal by supplementation. PMID:27534640

  9. Immobilization of iodine in concrete

    DOEpatents

    Clark, Walter E.; Thompson, Clarence T.

    1977-04-12

    A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3-20 wt. % iodine as Ba(IO.sub.3).sub.2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO.sub.3).sub.2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. BACKGROUND OF THE INVENTION This invention was made in the course of, or under a contract with the Energy Research and Development Administration. It relates in general to reactor waste solidification and more specifically to the immobilization of fission product radioactive iodine recovered from irradiated nuclear fuel for underground storage.

  10. [Iodine excess induced thyroid dysfunction].

    PubMed

    Egloff, Michael; Philippe, Jacques

    2016-04-20

    The principle sources of iodine overload, amiodarone and radiologic contrast media, are frequently used in modern medicine. The thyroid gland exerts a protective effect against iodine excess by suppressing iodine internalization into the thyrocyte and iodine organification, the Wolff-Chaikoff effect. Insufficiency of this effect or lack of escape from it leads to hypo- or hyperthyroidism respectively. Amiodarone induced thyrotoxicosis is a complex condition marked by two different pathophysiological mechanisms with different treatments. Thyroid metabolism changes after exposure to radiologic contrast media are frequent, but they rarely need to be treated. High risk individuals need to be identifed in order to delay the exam or to monitor thyroid function or apply prophylactic measures in selected cases. PMID:27276725

  11. CIN Iodine cyanide

    NASA Astrophysics Data System (ADS)

    Wlodarczak, G.

    This document is part of Subvolume B 'Linear Polyatomic Molecules' of Volume 29 'Molecular Constants Mostly from Microwave, Molecular Beam, and Sub-Doppler Laser Spectroscopy' of Landolt-Börnstein - Group II 'Molecules and Radicals'.

  12. [Physiopathology of iodine deficiency].

    PubMed

    Pinchera, A; Rago, T; Vitti, P

    1998-01-01

    The process of goitrogenesis is likely to be the consequence of an increased TSH stimulation linked to an initial reduction of circulating thyroid hormone caused by iodine deficiency (ID). Other growth factors associated to TSH may have a role in the pathogenesis of goiter. Natural history of goiter is the evolution towards nodularity and functional autonomy. This phenomenon is due to the heterogeneity of thyroid follicular cells, some of which, with an intrinsic elevated growth rate, under the stimulation of ID progress to nodule formation and hyperfunction. In multinodular goiter TSH receptor mutations activating adenylate cyclase-cAMP pathway were found. In a recent epidemiological survey it was shown that nodular goiter increased with the age, being about 1% in schoolchildren and 23% in the adults (56-75 years). Also nodular autonomy and hyperthyroidism were more frequent in the 36-75 year age group. Severe ID is also cause of endemic cretinism. In Europe minor neuropsychological impairments and cognitive deficits were described in areas of moderate ID. The exposure to a mild ID during fetal life causes minor neuropsychological damage. In conclusion, ID is responsible of goiter and its evolution towards nodularity and functional autonomy. Severe ID is also cause of endemic cretinism, while cognitive deficits and minor neuropsychological impairments were found in mild to moderate ID. PMID:10052165

  13. High-Performance Water-Iodinating Cartridge

    NASA Technical Reports Server (NTRS)

    Sauer, Richard; Gibbons, Randall E.; Flanagan, David T.

    1993-01-01

    High-performance cartridge contains bed of crystalline iodine iodinates water to near saturation in single pass. Cartridge includes stainless-steel housing equipped with inlet and outlet for water. Bed of iodine crystals divided into layers by polytetrafluoroethylene baffles. Holes made in baffles and positioned to maximize length of flow path through layers of iodine crystals. Resulting concentration of iodine biocidal; suppresses growth of microbes in stored water or disinfects contaminated equipment. Cartridge resists corrosion and can be stored wet. Reused several times before necessary to refill with fresh iodine crystals.

  14. Development of an online method for quantification of maritime molecular iodine and other gaseous iodine containing inorganic compounds

    NASA Astrophysics Data System (ADS)

    Götz, Sven; Hoffmann, Thorsten

    2014-05-01

    The atmospheric chemistry of iodine is important in multiple ways. The focus lies on the ability to influence the oxidizing capacity of the atmosphere, i.e. by destruction of ozone, and the formation of iodine oxide particles (IOP), i.e. the influence on condensation nuclei (CCN). Using a variation of techniques, like differential optical absorption spectroscopy (DOAS), laser-induced fluorescence (LIF), inductively coupled plasma mass spectrometry (ICP-MS) and atmospheric pressure chemical ionization with tandem mass spectrometry (APCI-MS/MS), the reactive iodine species of atomic iodine (I), molecular iodine (I2), iodine monoxide (IO) and iodine dioxide (OIO) have all been detected in the atmosphere from Antarctica to the equatorial marine boundary layer (MBL). In the past few years there have been active research on IO, especially after revealing significant levels in open ocean measurements, OIO and higher iodine oxides. In addition to atmospheric measurements, significant developments in laboratory kinetics, photochemistry and heterogeneous chemistry of iodine species have been accomplished. [1] Here we introduce an online-method for detecting gaseous molecular iodine and other gaseous iodine-containing inorganic compounds such as HOI, which is a further development of the technique used by Carpenter et al. [2]. The method is based on selective photolytic dissociation of the analytes, followed by oxidization and particle formation of the iodine compounds. The particles are than size-segregated and detected by a scanning mobility particle sizer (SMPS) system. Initial IOP forming is performed in a reaction chamber providing specific wavelengths according to corresponding bond dissociation thresholds. Atmospheric samples can also be pre concentrated by diffusion denuder (with α Cyclodextrin modified and immobilised silica coating) [3-5] and afterwards released by thermodesorption. First attempts of quantification are carried out by external calibration using an

  15. The changing epidemiology of iodine deficiency.

    PubMed

    Li, Mu; Eastman, Creswell J

    2012-07-01

    Globally, about 2 thousand million people are affected by iodine deficiency. Although endemic goitre is the most visible sign of iodine deficiency, its most devastating consequence is brain damage causing mental retardation in children. The relationship between iodine deficiency and brain damage was not clearly established until the 1980s when the term iodine deficiency disorders (IDDs), which encompass a spectrum of conditions caused by iodine deficiency, was introduced. This paradigm shift in the understanding of the clinical consequences of iodine deficiency led to a change in iodine deficiency assessment. The median urinary iodine excretion level has been recommended as the preferred indicator for monitoring population iodine deficiency status since 2001. The 2007 WHO urinary iodine data in schoolchildren from 130 countries revealed that iodine intake is still insufficient in 47 countries. Furthermore, about one-third of countries lack national estimates of the prevalence of iodine deficiency. The picture that has emerged from available data worldwide over the past two decades is that IDDs are not confined to remote, mountainous areas in developing countries, but are a global public health problem that affects most countries, including developed countries and island nations. The recognition of the universality of iodine deficiency highlights the need to develop and apply new strategies to establish and maintain sustainable IDD elimination and strengthen regular monitoring programmes. PMID:22473332

  16. The Absorption Spectrum of Iodine Vapour

    ERIC Educational Resources Information Center

    Tetlow, K. S.

    1972-01-01

    A laboratory experiment is described which presents some molecular parameters of iodine molecule by studying iodine spectrum. Points out this experiment can be conducted by sixth form students in high school laboratories. (PS)

  17. Synthetic applications of pseudocyclic hypervalent iodine compounds.

    PubMed

    Yoshimura, Akira; Yusubov, Mekhman S; Zhdankin, Viktor V

    2016-06-01

    Hypervalent iodine compounds have found wide practical application as versatile, efficient, and sustainable reagents for organic synthesis. Pseudocyclic hypervalent iodine derivatives are characterized by the presence of additional intramolecular non-covalent coordination at the iodine center, which leads to significant alteration of their physical and chemical properties. In comparison with common hypervalent iodine reagents, these pseudocyclic compounds have higher thermal stability, better solubility, and improved reactivity. In recent years, pseudocyclic hypervalent iodine reagents are increasingly used in organic synthesis as environmentally friendly selective oxidants and electrophiles. Furthermore, numerous enantioselective reactions mediated by chiral pseudocyclic hypervalent iodine species have been recently developed. In the present review, the preparation and structural features of pseudocyclic iodine(iii) and iodine(v) derivatives are discussed, and recent developments in their synthetic applications are summarized. PMID:27143521

  18. Towards graphene iodide: iodination of graphite oxide

    NASA Astrophysics Data System (ADS)

    Šimek, Petr; Klímová, Kateřina; Sedmidubský, David; Jankovský, Ondřej; Pumera, Martin; Sofer, Zdeněk

    2014-11-01

    Halogenated graphene derivatives are interesting owing to their outstanding physical and chemical properties. In this paper, we present various methods for the synthesis of iodinated graphene derivatives by the iodination of graphite oxides prepared according to either the Hummers or Hofmann method. Both graphite oxides were iodinated by iodine or hydroiodic acid under reflux or in an autoclave at elevated temperatures (240 °C) and pressures (over 100 bar). The influence of both graphite oxide precursors on the properties of resulting iodinated graphenes was investigated by various techniques, including SEM, SEM-EDS, high-resolution XPS, FTIR, STA, and Raman spectroscopy. Electrical resistivity was measured by a standard four point technique. In addition, the electrochemical properties were investigated by cyclic voltammetry. Although the iodinated graphenes were structurally similar, they had remarkably different concentrations of iodine. The most highly iodinated graphenes (iodine concentration above 30 wt%) exhibited relatively high C/O ratios, confirming high degrees of reduction. Iodine is incorporated in the form of covalent bonds to carbon atoms or as polyiodide anions non-covalently bonded through the charge transfer reaction with the graphene framework. Iodinated graphenes with such properties could be used as the starting material for further chemical modifications or as flame-retardant additives.Halogenated graphene derivatives are interesting owing to their outstanding physical and chemical properties. In this paper, we present various methods for the synthesis of iodinated graphene derivatives by the iodination of graphite oxides prepared according to either the Hummers or Hofmann method. Both graphite oxides were iodinated by iodine or hydroiodic acid under reflux or in an autoclave at elevated temperatures (240 °C) and pressures (over 100 bar). The influence of both graphite oxide precursors on the properties of resulting iodinated graphenes was

  19. Mineral resource of the month: iodine

    USGS Publications Warehouse

    Polyak, Désirée E.

    2009-01-01

    The article focuses on iodine, its benefits and adverse effects, and its production and consumption. It states that iodine is essential to humans for it produces thyroid hormones to nourish thyroid glands but excessive intake could cause goiter, hyperthyroidism or hypothyroidism. U.S. laws require salt iodization to help prevent diseases. Chile and Japan are the world's leading iodine producer while in the U.S. iodine is mined from deep well brines in northern Oklahoma.

  20. Sublimation of Iodine at Various Pressures

    ERIC Educational Resources Information Center

    Leenson, Ilya A.

    2005-01-01

    Various phenomena that are observed in the process of heating solid iodine in closed vessels at different pressures and temperatures are described. When solid iodine is heated in an evacuated ampoule where the pressure is less than 10(super -3), no noticeable color appears and immediate condensation of tiny iodine crystals is visible higher up on…

  1. Kinetics of an oxygen - iodine active medium with iodine atoms optically pumped on the 2P1/2 - 2P3/2 transition

    NASA Astrophysics Data System (ADS)

    Zagidullin, M. V.; Malyshev, M. S.; Azyazov, V. N.

    2015-08-01

    The kinetics of the processes occurring in an O2 - I2 - He - H2O gas flow in which photodissociation of molecular iodine at a wavelength close to 500 nm and excitation of atomic iodine on the 2P1/2 - 2P3/2 transition by narrow-band radiation near 1315 nm are implemented successively has been analysed. It is shown that implementation of these processes allows one to form an oxygen - iodine medium with a high degree of dissociation of molecular iodine and a relative content of singlet oxygen O2(a1Δ) exceeding 10%. Having formed a supersonic gas flow with a temperature ~100 K from this medium, one can reach a small-signal gain of about 10-2 cm-1 on the 2P1/2 - 2P3/2 transition in iodine atoms. The specific power per unit flow cross section in the oxygen - iodine laser with this active medium may reach ~100 W cm-2.

  2. Iodine losses during Winkler titrations

    NASA Astrophysics Data System (ADS)

    Knapp, George P.; Stalcup, Marvel C.; Stanley, Robert J.

    1991-01-01

    An experiment designed to measure iodine loss during the aliquot version of the Winkler titration for dissolved oxygen in seawater shows that 0.01-0.03 ml l -1 equivalent oxygen is lost at typical oceanic concentrations in the method presently used. A standardization technique, which mimics that employed during the titration of seawater samples, compensates for this iodine loss throughout the oceanic range. This result, contradicting an earlier report by GREEN and CARRITT (1966, Analyst, 91, 207-208), demonstrates that the whole-bottle method of oxygen titration is not to be preferred over the aliquot method.

  3. Infinite Polyiodide Chains in the Pyrroloperylene-Iodine Complex: Insights into the Starch-Iodine and Perylene-Iodine Complexes.

    PubMed

    Madhu, Sheri; Evans, Hayden A; Doan-Nguyen, Vicky V T; Labram, John G; Wu, Guang; Chabinyc, Michael L; Seshadri, Ram; Wudl, Fred

    2016-07-01

    We report the preparation and X-ray crystallographic characterization of the first crystalline homoatomic polymer chain, which is part of a semiconducting pyrroloperylene-iodine complex. The crystal structure contains infinite polyiodide I∞ (δ-) . Interestingly, the structure of iodine within the insoluble, blue starch-iodine complex has long remained elusive, but has been speculated as having infinite chains of iodine. Close similarities in the low-wavenumber Raman spectra of the title compound and starch-iodine point to such infinite polyiodide chains in the latter as well. PMID:27239781

  4. Enabling lunar and space missions by laser power transmission

    NASA Technical Reports Server (NTRS)

    Deyoung, R. J.; Nealy, J. E.; Humes, D. H.; Meador, W. E.

    1992-01-01

    Applications are proposed for laser power transmission on the Moon. A solar-pumped laser in lunar orbit would beam power to the lunar surface for conversion into either electricity or propulsion needs. For example, lunar rovers could be much more flexible and lighter than rovers using other primary power sources. Also, laser power could be absorbed by lunar soil to create a hard glassy surface for dust-free roadways and launch pads. Laser power could also be used to power small lunar rockets or orbital transfer vehicles, and finally, photovoltaic laser converters could power remote excavation vehicles and human habitats. Laser power transmission is shown to be a highly flexible, enabling primary power source for lunar missions.

  5. Advanced prototype automated iodine monitor system

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The technique of detecting and measuring parts-per-million concentrations of aqueous iodine by direct spectrophotometric means is discussed, and development of a prototype Automated Iodine Monitoring/Controller System (AIMS) is elaborated. The present effort is directed primarily toward reducing the power requirement and the weight of the AIMS. Other objectives include determining the maximum concentration of iodine that can be dissolved in an alcohol solution, and in an aqueous potassium iodide solution. Also discussed are the effects of a no flow condition on iodine measurements and the effect of pH on spectrophotometric iodine determinations.

  6. Iodine supplementation in pregnancy - is it time?

    PubMed

    Taylor, P N; Vaidya, B

    2016-07-01

    Iodine is essential for the synthesis of thyroid hormone and optimal foetal neurological development. Pregnant women living in borderline or moderate-severe iodine deficient areas are at particularly high risk of being iodine deficient, and this may have important clinical consequences, particularly for the neurocognitive development of the offspring. It is a substantial problem and many countries including the United Kingdom are mild-moderately iodine deficient. Although the detrimental effects of severe iodine deficiency are well recognized, the benefits of correcting mild-to-moderate iodine deficiency are unclear due to a lack of randomized controlled trials in this area. However, observational data increasingly indicate that there may be substantial health and economic benefits from correcting iodine deficiency in pregnancy. There is now a growing trend from learned societies that iodine supplementation should be utilized in pregnancy in countries with mild-to-moderate iodine deficiency. The dose of iodine supplement needs to reflect local iodine status and iodization policies and will need careful monitoring at the population level to ensure doses to prevent under/excess dosing which would undermine the potential benefits. National tailored guidance is therefore essential. PMID:26998765

  7. An iodine-based frequency reference for space applications

    NASA Astrophysics Data System (ADS)

    Schuldt, Thilo; Johann, Ulrich; Doeringshoff, Klaus; Kovalchuk, Evgeny; Peters, Achim; Braxmaier, Claus; Pahl, Julia; Stuehler, Johannes; Franz, Matthias

    We present the development of an iodine-based frequency reference for future potential applications in space, including the gravitational wave detector LISA/eLISA (Laser Interferometer Space Antenna), the mini SpaceTime Asymmetry Research (mSTAR) program, the aperture-synthesis telescope Darwin and the GRACE (Gravity Recovery and Climate Experiment) follow on mission/NGGM (Next Generation Gravity Mission) exploring Earth's gravity. Based on a state-of-the-art laboratory iodine frequency reference, setups on elegant breadboard (EBB) and engineering model (EM) level were realized, taking into account specific design criteria for space compatibility such as compactness and robustness. Both setups employ modulation transfer spectroscopy (MTS) in combination with balanced detection. They use a baseplate made of glass material in combination with a dedicated easy-to-handle assembly-integration technology (adhesive bonding) ensuring high pointing stability of the two counter-propagating laser beams in the iodine cell and therefore high long-term stability. The EBB setup utilizes a commercial off-the-shelf 30 cm long iodine cell in triple-pass configuration, the EM setup a specifically designed and manufactured compact iodine cell made of fused silica in a nine-pass configuration with a specific robust cold finger design. Both setups were characterized in beat measurements with a ULE cavity setup. Similar frequency stabilities of about 1*10 (-14) at an integration time of 1 s and below 5*10 (-15) at integration times between 10 s and 100 s were demonstrated. These values are comparable to the currently best laboratory setups. The EM setup was further subjected to environmental testing including thermal cycling and vibrational testing. Financial support by the German Space Agency DLR with funds provided by the Federal Ministry of Economics and Technology (BMWi) under grant numbers 50 QT 1102 and 50 QT 1201 is highly appreciated. The authors thank Jan Hrabina and Josef Lazar

  8. Iodine requirements and the risks and benefits of correcting iodine deficiency in populations.

    PubMed

    Zimmermann, Michael B

    2008-01-01

    Iodine deficiency has multiple adverse effects on growth and development due to inadequate thyroid hormone production that are termed the iodine deficiency disorders (IDD). IDD remains the most common cause of preventable mental impairment worldwide. IDD assessment methods include urinary iodine concentration, goiter, thyroglobulin and newborn thyrotropin. In nearly all iodine-deficient countries, the best strategy to control IDD is salt iodization, one of the most cost-effective ways to contribute to economic and social development. When salt iodization is not possible, iodine supplements can be targeted to vulnerable groups. Introduction of iodized salt to regions of chronic IDD may transiently increase the incidence of thyroid disorders, and programs should include monitoring for both iodine deficiency and excess. Although more data on the epidemiology of thyroid disorders caused by differences in iodine intake are needed, overall, the relatively small risks of iodine excess are far outweighed by the substantial risks of iodine deficiency. PMID:18565420

  9. An innovative approach for iodine supplementation using iodine-rich phytogenic food.

    PubMed

    Weng, Huan-Xin; Liu, Hui-Ping; Li, De-Wang; Ye, Mingli; Pan, Lehua; Xia, Tian-Hong

    2014-08-01

    Iodine, as one of the essential trace elements for human body, is very important for the proper function of thyroid gland. In some regions, people are still suffering from iodine deficiency disorder (IDD). How to provide an effective and cost-efficient iodine supplementation has been a public health issue for many countries. In this review, a novel iodine supplementation approach is introduced. Different from traditional iodine salt supplement, this approach innovatively uses cultivated iodine-rich phytogenic food as the supplement. These foods are cultivated using alga-based organic iodine fertilizer. The feasibility, mechanics of iodine absorption of plants from soil and the bioavailability of iodine-rich phytogenic food are further discussed. PMID:24504625

  10. Mechanism of iodine uptake by cabbage: effects of iodine species and where it is stored.

    PubMed

    Weng, Huan-Xin; Hong, Chun-Lai; Yan, Ai-Lan; Pan, Le-Hua; Qin, Ya-Chao; Bao, Lü-Ting; Xie, Ling-Li

    2008-10-01

    Iodine-enhanced vegetable has been proven to be an effective way to reduce iodine deficiency disorders in many regions. However, the knowledge about what mechanisms control plant uptake of iodine and where iodine is stored in plants is still very limited. A series of controlled experiments, including solution culture, pot planting, and field experiments were carried out to investigate the uptake mechanism of iodine in different forms. A new methodology for observing the iodine distribution within the plant tissues, based on AgI precipitation reaction and transmission electron microscope techniques, has been developed and successfully applied to Chinese cabbage. Results show that iodine uptake by Chinese cabbage was more effective when iodine was in the form of IO(3) (-) than in the form of I(-) if the concentration was low (<0.5 mg L(-1)), but the trend was opposite if iodine concentration was 0.5 mg L(-1) or higher. The uptake was more sensitive to metabolism inhibitor in lower concentration of iodine, which implies that the uptake mechanism transits from active to passive as the iodine concentration increases, especially when the iodine is in the form of IO(3) (-). The inorganic iodine fertilizer provided a quicker supply for plant uptake, but the higher level of iodine was toxic to plant growth. The organic iodine fertilizer (seaweed composite) provided a more sustainable iodine supply for plants. Most of the iodine uptake by the cabbage is intercepted and stored in the fibrins in the root while the iodine that is transported to the above-ground portion (shoots and leaves) is selectively stored in the chloroplasts. PMID:18521548

  11. Laser Welding in Space

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Kaukler, William F.

    1989-01-01

    Solidification type welding process experiments in conditions of microgravity were performed. The role of convection in such phenomena was examined and convective effects in the small volumes obtained in the laser weld zone were observed. Heat transfer within the weld was affected by acceleration level as indicated by the resulting microstructure changes in low gravity. All experiments were performed such that both high and low gravity welds occurred along the same weld beam, allowing the effects of gravity alone to be examined. Results indicate that laser welding in a space environment is feasible and can be safely performed IVA or EVA. Development of the hardware to perform the experiment in a Hitchhiker-g platform is recomended as the next step. This experiment provides NASA with a capable technology for welding needs in space. The resources required to perform this experiment aboard a Shuttle Hitchhiker-pallet are assessed. Over the four year period 1991 to 1994, it is recommended that the task will require 13.6 manyears and $914,900. In addition to demonstrating the technology and ferreting out the problems encountered, it is suggested that NASA will also have a useful laser materials processing facility for working with both the scientific and the engineering aspects of materials processing in space. Several concepts are also included for long-term optimization of available solar power through solar pumping solid state lasers directly for welding power.

  12. Geochemical Cycling of Iodine Species in Soils

    SciTech Connect

    Hu, Q; Moran, J E; Blackwood, V

    2007-08-23

    Iodine is an important element in studies of environmental protection and human health, global-scale hydrologic processes and nuclear nonproliferation. Biogeochemical cycling of iodine in soils is complex, because iodine occurs in multiple oxidation states and as inorganic and organic species that may be hydrophilic, atmophilic, and biophilic. In this study, we applied new analytical techniques to study the content and speciation of stable iodine in representative surface soils, and sorption and transport behavior of iodine species (iodide, iodate, and 4-iodoaniline) in sediments collected at numerous nuclear facilities in the United States, where anthropogenic {sup 129}I from prior nuclear fuel processing activities poses an environmental risk. The surface soil samples were chosen for their geographic locations (e.g., near the ocean or nuclear facilities) and for their differing physico-chemical characteristics (organic matter, texture, etc). Extracted solutions were analyzed by IC and ICP-MS methods to determine iodine concentrations and to examine iodine speciation (iodide, iodate, and organic iodine). In natural soils, iodine is mostly (nearly 90% of total iodine) present as organic species, while inorganic iodine becomes important (up to 50%) only in sediments with low organic matter. Results from laboratory column studies, aimed at examining transport of different iodine species, showed much greater retardation of 4-iodoaniline than iodide or iodate. Careful attention must be given to potential interconversion among species when interpreting the biogeochemical behavior of iodine in the environment. In addition to speciation, input concentration and residence time effects will influence the biogeochemical cycling of anthropogenic 129I deposited on surface soils.

  13. Effects of iodine intake and teat-dipping practices on milk iodine concentrations in dairy cows.

    PubMed

    Castro, S I Borucki; Berthiaume, R; Robichaud, A; Lacasse, P

    2012-01-01

    Two studies were conducted to determine the effects of dietary iodine and teat-dipping practices on iodine concentrations in milk. In the first study, 63 cows in mid lactation were assigned to a 3×3 factorial design in which the main effects were dietary iodine levels (0.3, 0.6, and 0.9 mg of dietary I/kg of dry matter) and 3 different postdip managements (chlorhexidine with dip cup, 1% iodine dip cup, and 1% iodine by manual spray). During the 13-d pre-experimental period and the 15-d experimental period, noniodized sanitizers were used in premilking management. During the pre-experimental period, the levels of milk iodine averaged 241.2±5.8 μg/kg, and no relationship was found with lactation number, days in milk, or milk production. Milk iodine concentrations increased linearly with iodine intake. Although teat dipping with 1% iodine had no effect on milk iodine concentration, the same solution applied by spraying greatly increased milk iodine levels. The second study was conducted to determine the effects of udder preparation before milking on milk iodine concentrations. Thirty-two lactating cows were assigned to 4 treatments: no predip (Con); predip with a predip solution containing 0.5% iodine+complete cleaning (Comp); predip with a postdip solution containing 1% iodine+complete cleaning (Post); and predip with a predip solution containing 0.5% iodine+incomplete cleaning (Inc). During the 14-d pre-experimental period and the 19-d experimental period, cows were fed the same diet, and noniodized sanitizers were used for postmilking dipping. During the last week of treatment, milk iodine averaged 164, 189, 218, and 252±9.8 μg/kg for Con, Comp, Post, and Inc, respectively. Preplanned orthogonal contrasts indicated that predipping with a 0.5% iodine predip solution completely wiped off (Comp) tended to increase milk iodine content above that of the control and that the iodine content of Post and Inc were higher than that of the Comp treatment. The results of

  14. Graphs for 53-I (Iodine)

    NASA Astrophysics Data System (ADS)

    Sukhoruchkin, S. I.; Soroko, Z. N.

    This document is part of the Supplement containing the complete sets of data of Subvolume A `Nuclei with Z = 1 - 54' of Volume 22 `Nuclear Binding Energies and Atomic Masses' of Landolt-Börnstein - Group I `Elementary Particles, Nuclei and Atoms'. It provides a graphic representation of nucleon separation energies and residual interaction parameters for isotopes of the chemical element 53-I (Iodine, atomic number Z = 53).

  15. Effect of iodine disinfectant source and water quality parameters on soluble iodine speciation

    NASA Technical Reports Server (NTRS)

    Silverstein, Joann; Hurst, Charles; Barkley, Robert; Dunham, Andrew

    1993-01-01

    Investigations of iodine species distribution of various aqueous solutions of iodine disinfectants and water from equilibrated suspensions of triodide and pentaiodide resins were done at the University of Colorado for the Center for Space Environmental Health during 1992 and 1993. Direct measurements of three individual iodine species: I(-), I2 and I3(-), were made. In addition three measures of total titratable iodine species were used. It has been found that I2 and I3(-) solutions produce a significant fraction of the non-disinfecting species iodine I(-), ranging from 50 to 80% of added iodine, respectively, at pH values of approximately 5. Correspondingly, I2 solutions produce more than twice the concentration of disinfecting iodine species per mass iodine dose than I3(-) solutions. Both I(-) and I2 species were found in aqeuous extracts of pentaiodide resin, although no soluble species were detected with triiodide resin.

  16. Iodine deficiency disorders (IDD) and their eradication.

    PubMed

    Hetzel, B S

    1983-11-12

    Disorders resulting from severe iodine deficiency affect more than 400 million people in Asia alone. These disorders include stillbirths, abortions, and congenital anomalies; endemic cretinism, characterised most commonly by mental deficiency, deaf mutism, and spastic diplegia and lesser degrees of neurological defect related to fetal iodine deficiency; and impaired mental function in children and adults with goitre associated with subnormal concentrations of circulating thyroxine. Use of the term iodine deficiency disorders, instead of "goitre", would help to bridge the serious gap between knowledge and its application. Iodised salt and iodised oil (by injection or by mouth) are suitable for the correction of iodine deficiency on a mass scale. A single dose of iodised oil can correct severe iodine deficiency for 3-5 years. Iodised oil offers a satisfactory immediate measure for primary care services until an iodised salt programme can be implemented. The complete eradication of iodine deficiency is therefore feasible within 5-10 years. PMID:6138653

  17. Injection of iodine to the stratosphere

    NASA Astrophysics Data System (ADS)

    Saiz-Lopez, A.; Baidar, S.; Cuevas, C. A.; Koenig, T. K.; Fernandez, R. P.; Dix, B.; Kinnison, D. E.; Lamarque, J.-F.; Rodriguez-Lloveras, X.; Campos, T. L.; Volkamer, R.

    2015-08-01

    We report a new estimation of the injection of iodine into the stratosphere based on novel daytime (solar zenith angle < 45°) aircraft observations in the tropical tropopause layer and a global atmospheric model with the most recent knowledge about iodine photochemistry. The results indicate that significant levels of total reactive iodine (0.25-0.7 parts per trillion by volume), between 2 and 5 times larger than the accepted upper limits, can be injected into the stratosphere via tropical convective outflow. At these iodine levels, modeled iodine catalytic cycles account for up to 30% of the contemporary ozone loss in the tropical lower stratosphere and can exert a stratospheric ozone depletion potential equivalent to, or even larger than, that of very short-lived bromocarbons. Therefore, we suggest that iodine sources and chemistry need to be considered in assessments of the historical and future evolution of the stratospheric ozone layer.

  18. Discovery and Early Uses of Iodine

    NASA Astrophysics Data System (ADS)

    Rosenfeld, Louis

    2000-08-01

    The ancient Chinese recognized goiter and the therapeutic effects of burnt sponge and seaweed in reducing its size or causing its disappearance. The modern use of iodine in the prevention of goiter dates from 1830, when it was proposed that goiter is an iodine deficiency disease due to lack of iodine in the water supply. But unfavorable symptoms of iodism were frequent owing to overenthusiastic use and overdose of iodine. Consequently, iodide prophylaxis was discredited and abandoned. The presence of iodine in organic combination as a normal constituent of the thyroid was established in 1896 and the use of iodine in treatment and prevention of goiter was revived. In 1917 the general use of iodized salt in goitrous areas was shown to be effective in preventing simple endemic goiter.

  19. Atmospheric science: marine aerosols and iodine emissions.

    PubMed

    McFiggans, Gordon

    2005-02-10

    O'Dowd et al. describe the formation of marine aerosols from biogenic iodine and the growth of these aerosols into cloud-condensation nuclei (CCN). Based on chamber and modelling results, the authors suggest that biogenic organic iodine compounds emitted from macroalgae may be responsible for coastal particle bursts and that production of these compounds in the open ocean could increase CCN there too. It has since been shown that coastal particles are more likely to be produced from the photooxidation of molecular iodine. Moreover, I contend that open-ocean particle production and cloud enhancement do not result from emissions of organic iodine at atmospheric levels. For iodine particles to affect cloud properties over the remote ocean, an additional source of iodine is necessary as organic precursors cannot be responsible. PMID:15703706

  20. Disposal of radioactive iodine in space

    NASA Technical Reports Server (NTRS)

    Burns, R. E.; Defield, J. G.

    1978-01-01

    The possibility of space disposal of iodine waste from nuclear power reactors is investigated. The space transportation system utilized relies upon the space shuttle, a liquid hydrogen/liquid oxygen orbit transfer vehicle, and a solid propellant final stage. The iodine is assumed to be in the form of either an iodide or an iodate, and calculations assume that the final destination is either solar orbit or solar system escape. It is concluded that space disposal of iodine is feasible.

  1. Solid state lithium-iodine primary battery

    SciTech Connect

    Sekido, S.; Ninomiya, Y.; Sotomura, T.

    1984-01-10

    A solid-state primary cell comprising a lithium anode, an iodine cathode containing a charge transfer complex and a solid lithium iodide electrolyte doped with a 1-normal-alkyl-pyridinium iodide. The anode surface can be coated with LiOH or Li/sub 3/N. The iodine cathode comprises a complex of iodine and 1-normal-alkyl-pyridinium iodide and preferably contains titanium dioxide powder, alumina gel powder or silica gel powder admixed with the complex.

  2. [CME: Radioactive iodine therapy in thyroid cancer].

    PubMed

    Steinert, Hans C; Aberle, Susanne

    2015-11-11

    Differentiated thyroid carcinomas represent about 90% of all thyroid tumors and are divided in papillary and follicular carcinomas. Their prognosis is good, however, recurrences are not rare. Their ability to accumulate iodine is used for the radioactive iodine treatment. The aim of the postoperative radioactive iodine ablation therapy is the complete elimination of remnant thyroid cells and sensitive staging (Fig. 1). The recurrence rate decreases after a complete thyroid ablation. Furthermore, thyroglobulin can be used as a sensitive tumor marker. Radioactive iodine treatment by itself describes the therapy of metastases. An exception is the papillary microcarcinoma, which in general is treated by a lobectomy alone. PMID:26558927

  3. Chalcogenide aerogels as sorbents for radioactive iodine

    SciTech Connect

    Subrahmanyam, Kota S.; Sarma, Debajit; Malliakas, Christos; Polychronopoulou, Kyriaki; Riley, Brian J.; Pierce, David A.; Chun, Jaehun; Kanatzidis, Mercouri G.

    2015-04-14

    Iodine (129I) is one of the radionuclides released in nuclear fuel reprocessing and poses risk to public safety due to its involvement in human metabolic processes. In order to prevent the leaching of hazardous radioactive iodine into the environment, its effective capture and sequestration is pivotal. In the context of finding a suitable matrix for capturing radioactive iodine the chalcogels, NiMoS4, CoMoS4, Sb4Sn4S12, Zn2Sn2S6, and CoSx (x = 4-5) were explored as iodine sorbents. All the chalcogels showed high uptake, reaching up to 225 mass% (2.25 g/g) of the final mass owing to strong chemical and physical iodine-chalcogen interactions. Analysis of the iodine-loaded specimens revealed that the iodine chemically reacted with Sb4Sn4S12, Zn2Sn2S6, and CoSx to form metal complexes SbI3, SnI4, and, KI respectively. The NiMoS4 and CoMoS4 chalcogels did not appear to undergo a chemical reaction with iodine since iodide complexes were not observed with these samples. Once heated, the iodine-loaded chalcogels released iodine in the temperature range of 75 °C to 220 °C, depending on the nature of iodine speciation. In the case of Sb4Sn4S12 and Zn2Sn2S6 iodine release was observed around 150 °C in the form of SnI4 and SbI3, respectively. The NiMoS4, CoMoS4, and CoSx released iodine at ~75 °C, which is consistent with physisorbed iodine. Preliminary investigations on consolidation of iodine-loaded Zn2Sn2S6 with Sb2S3 as a glass forming additive showed the content of iodine in consolidated glass ingots at around 25 mass%.

  4. Injection of iodine to the stratosphere

    NASA Astrophysics Data System (ADS)

    Saiz-Lopez, Alfonso; Baidar, Sunil; Cuevas, Carlos A.; Koening, Theodore; Fernandez, Rafael P.; Dix, Barbara; Kinnison, Douglas E.; Lamarque, Jean-Francois; Rodriguez-Lloveras, Xavier; Campos, Teresa L.; Volkamer, Rainer

    2016-04-01

    There are still many uncertainties about the influence of iodine chemistry in the stratosphere, as the real amount of reactive iodine injected to this layer the troposphere and the partitioning of iodine species are still unknown. In this work we report a new estimation of the injection of iodine into the stratosphere based on novel daytime (SZA < 45°) aircraft observations in the tropical tropopause layer (TORERO campaign) and a 3D global chemistry-climate model (CAM-Chem) with the most recent knowledge about iodine photochemistry. The results indicate that significant levels of total reactive iodine (0.25-0.7 pptv), between 2 and 5 times larger than the accepted upper limits, could be injected into the stratosphere via tropical convective outflow. At these iodine levels, modelled iodine catalytic cycles account for up to 30% of the contemporary ozone loss in the tropical lower stratosphere and can exert a stratospheric ozone depletion potential equivalent or even larger than that of very short-lived bromocarbons. Therefore, we suggest that iodine sources and chemistry need to be considered in assessments of the historical and future evolution of the stratospheric ozone layer.

  5. Automated iodine monitor system. [for aqueous solutions

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The feasibility of a direct spectrophotometric measurement of iodine in water was established. An iodine colorimeter, was built to demonstrate the practicality of this technique. The specificity of this method was verified when applied to an on-line system where a reference solution cannot be used, and a preliminary design is presented for an automated iodine measuring and controlling system meeting the desired specifications. An Automated iodine monitor/controller system based on this preliminary design was built, tested, and delivered to the Johnson Space Center.

  6. Urinary iodine, thyroid function, and thyroglobulin as biomarkers of iodine status.

    PubMed

    Pearce, Elizabeth N; Caldwell, Kathleen L

    2016-09-01

    The accurate assessment of population iodine status is necessary to inform public health policies and clinical research on iodine nutrition, particularly the role of iodine adequacy in normal neurodevelopment. Urinary iodine concentration (UIC) directly reflects dietary iodine intake and is the most common indicator used worldwide to assess population iodine status. The CDC established the Ensuring the Quality of Iodine Procedures program in 2001 to provide laboratories that measure urinary iodine with an independent assessment of their analytic performance; this program fosters improvement in the assessment of UIC. Clinical laboratory tests of thyroid function (including serum concentrations of the pituitary hormone thyrotropin and the thyroid hormones thyroxine and triiodothyronine) are sometimes used as indicators of iodine status, although such use is often problematic. Even in severely iodine-deficient regions, there is a great deal of intraindividual variation in the ability of the thyroid to adapt. In most settings and in most population subgroups other than newborns, thyroid function tests are not considered sensitive indicators of population iodine status. However, the thyroid-derived protein thyroglobulin is increasingly being used for this purpose. Thyroglobulin can be measured in either serum or dried blood spot (DBS) samples. The use of DBS samples is advantageous in resource-poor regions. Improved methodologies for ascertaining maternal iodine status are needed to facilitate research on developmental correlates of iodine status. Thyroglobulin may prove to be a useful biomarker for both maternal and neonatal iodine status, but validated assay-specific reference ranges are needed for the determination of iodine sufficiency in both pregnant women and neonates, and trimester-specific ranges are possibly needed for pregnant women. UIC is currently a well-validated population biomarker, but individual biomarkers that could be used for research, patient care

  7. Exploding conducting film laser pumping apparatus

    DOEpatents

    Ware, K.D.; Jones, C.R.

    1984-04-27

    The 342-nm molecular iodine and the 1.315-..mu..m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

  8. Iodine transport analysis in the ESBWR.

    SciTech Connect

    Kalinich, Donald A.; Gauntt, Randall O.; Young, Michael Francis; Longmire, Pamela

    2009-03-01

    A simplified ESBWR MELCOR model was developed to track the transport of iodine released from damaged reactor fuel in a hypothesized core damage accident. To account for the effects of iodine pool chemistry, radiolysis of air and cable insulation, and surface coatings (i.e., paint) the iodine pool model in MELCOR was activated. Modifications were made to MELCOR to add sodium pentaborate as a buffer in the iodine pool chemistry model. An issue of specific interest was whether iodine vapor removed from the drywell vapor space by the PCCS heat exchangers would be sequestered in water pools or if it would be rereleased as vapor back into the drywell. As iodine vapor is not included in the deposition models for diffusiophoresis or thermophoresis in current version of MELCOR, a parametric study was conducted to evaluate the impact of a range of iodine removal coefficients in the PCCS heat exchangers. The study found that higher removal coefficients resulted in a lower mass of iodine vapor in the drywell vapor space.

  9. Thioamination of Alkenes with Hypervalent Iodine Reagents

    PubMed Central

    Mizar, Pushpak; Niebuhr, Rebecca; Hutchings, Matthew; Farooq, Umar; Wirth, Thomas

    2016-01-01

    An efficient thioamination of alkenes mediated by iodine(III) reagents is described. The use of different sulfur nucleophiles allows the flexible synthesis of 1,2-aminothiols from alkenes. By employing chiral iodine(III) reagents, a stereoselective version of the thioamination protocol has also been developed. PMID:26660291

  10. An Iodine Fluorescence Quenching Clock Reaction

    ERIC Educational Resources Information Center

    Weinberg, Richard B.; Muyskens, Mark

    2007-01-01

    Clock reactions based upon competing oxidation and reduction reactions of iodine and starch as the most popular type of chemistry example is presented to illustrate the redox phenomena, reaction kinetics, and principles of chemical titration. The examination of the photophysical principles underlying the iodine fluorescence quenching clock…

  11. [Adaptation of thyroid function to excess iodine].

    PubMed

    Aurengo, Andre; Leenhardt, Laurence; Aurengo, Helyett

    2002-10-26

    NORMALLY: The production of thyroid hormones is normally stable, despite iodine supplies that may vary widely and even on sudden excess iodine. The metabolism of iodine is characterised by adapted thyroid uptake, the requirements varying on the age and physiological status of the individual (pregnancy, breastfeeding) and by insufficient supplies in several areas in France. IN THE CASE OF EXCESS: The mechanisms that permit the thyroid to adapt to a sudden or chronic excess of iodine are immature in the newborn and sometimes deficient in adults, and may lead to iodine-induced dysthyroidism. Thanks to the recent progress made in thyroid physiology, these mechanisms are now better known. PATHOLOGICAL IMPACT: Iodine-induced hyperthyroidisms in a healthy or pathological thyroid are frequent. They are predominantly related to amiodarone. Iodine-related hypothyroidism frequently appears in cases of pre-existing thyroid diseases (asymptomatic autoimmune thyroiditis, for example). They are frequent in the newborn, notably in the premature. The iodine prophylaxis organised in Poland following the Tchernobyl accident led to very few pathological consequences in adults or children. PMID:12448332

  12. Iodine deficiency in vegetarians and vegans.

    PubMed

    Krajcovicová-Kudlácková, M; Bucková, K; Klimes, I; Seboková, E

    2003-01-01

    Iodine content in food of plant origin is lower in comparison with that of animal origin due to a low iodine concentration in soil. Urinary iodine excretion was assessed in 15 vegans, 31 lacto- and lacto-ovovegetarians and 35 adults on a mixed diet. Iodine excretion was significantly lower in alternative nutrition groups - 172 microg/l in vegetarians and 78 microg/l in vegans compared to 216 microg/l in subjects on a mixed diet. One fourth of the vegetarians and 80% of the vegans suffer from iodine deficiency (iodine excretion value below 100 microg/l) compared to 9% in the persons on a mixed nutrition. The results show that under conditions of alternative nutrition, there is a higher prevalence of iodine deficiency, which might be a consequence of exclusive or prevailing consumption of food of plant origin, no intake of fish and other sea products, as well as reduced iodine intake in the form of sea salt. PMID:12748410

  13. Immobilization of iodine in soil-water systems and its relation to iodine species

    NASA Astrophysics Data System (ADS)

    Shimamoto, Y.; Takahashi, Y.

    2009-12-01

    Iodine tends to accumulate in thyroid, and radioactive 131I and 129I are threatening to human health both short-term and long-term, respectively. It is thus important to understand iodine behavior in surface environments. Possible iodine species are I-, IO3-, I2, and organo-iodine species. X-ray absorption near-edge structure (XANES) and high performance liquid chromatography (HPLC) connected to ICP-MS were used to determine iodine species in soil and pore water, respectively. Soil and pore water samples were collected at depths of 0 to 12 cm near a tube well in Yoro, Chiba, Japan, where surface soil is flooded with brine containing iodine of 5.8 mg/L. Soil samples were also collected at depths of 0 to 90 cm in Yakushima Island, Kagoshima, Japan. The soil samples were frozen, and iodine K-edge XANES were measured at BL01B1, SPring-8 (Hyogo, Japan). Soil samples were buried into resin and prepared as thin sections, and mapping of iodine in soil grain was obtained using μ-XRF analysis at BL37XU, SPring-8. HPLC-ICP-MS, equipped with anion exchange or size exclusion column, was used to determine iodine species in pore water. Yoro: The depth profile of iodine concentration in soil correlates quite well with that of organic carbon content. XANES spectra are almost identical to that of humic substances at any depth (Fig. 1). Iodine mapping shows that iodine exists in organic matter more than clay minerals and iron rich mineral. Iodine in pore water exists as I- and organic iodine bound to dissolved humic substances at 0-6 cm, and mainly as I- at 9-12 cm, respectively. Thus, iodine tends to be bound to organic materials in soil as organic iodine, where as iodine in pore water exists mainly as I-. Yakushima: Iodine concentration is higher in volcanic ash soil layer (25-55 cm) than surface organic rich soil layer (0-25 cm). XANES spectrum of volcanic ash soil was different from those of reference materials (Fig. 1). Volcanic ash soil in Yakushima contains imogolite and

  14. Singlet oxygen generation using iodinated squaraine and squaraine-rotaxane dyes†

    PubMed Central

    Arunkumar, Easwaran; Sudeep, Pallikkara K.; Kamat, Prashant V.; Noll, Bruce C.

    2010-01-01

    The goal of this study was to assess the ability of squaraine-rotaxanes to generate singlet oxygen for potential application in photodynamic therapy (PDT). Specifically, we compare the aggregation and photophysical properties of an iodinated squaraine dye and an iodinated squaraine-rotaxane. Even under strongly aggregating conditions, the absorption spectra of both remain relatively sharp. An X-ray crystal structure of the iodinated squaraine dye shows that it adopts perpendicular, end-to-face orientations in the solid state. Singlet oxygen generation efficiency was measured by trapping with 1,3-diphenylisobenzofuran. The triplet state of the rotaxane was characterized using laser flash photolysis. The results of this study suggest that heavily halogenated squaraine-rotaxanes have potential as singlet oxygen photosensitizers for PDT. PMID:20376333

  15. Spectral properties of molecular iodine in absorption cells filled to specified saturation pressure.

    PubMed

    Hrabina, Jan; Šarbort, Martin; Acef, Ouali; Burck, Frédéric Du; Chiodo, Nicola; Holá, Miroslava; Číp, Ondřej; Lazar, Josef

    2014-11-01

    We present the results of measurement and evaluation of spectral properties of iodine absorption cells filled at certain saturation pressure. A set of cells made of borosilicate glass instead of common fused silica was tested for their spectral properties in greater detail with special care for the long-term development of the absorption media purity. The results were compared with standard fused silica cells and the high quality of iodine was verified. A measurement method based on an approach relying on measurement of linewidth of the hyperfine transitions is proposed as a novel technique for iodine cell absorption media purity evaluation. A potential application in laser metrology of length is also discussed. PMID:25402909

  16. Eliminating iodine deficiency: obstacles and their removal.

    PubMed

    Padilla, Carmencita David; Fagela-Domingo, Carmelita

    2008-12-01

    Iodine deficiency remains a global concern for developing countries and some industrialised countries. Iodine deficiency is the most common cause of preventable mental retardation, posing a threat to the social and economic development of countries. Initiatives were developed and instituted to accelerate progress to achieve the goal of universal salt iodisation (USI). However, these efforts were not successful in eliminating iodine deficiency disorders (IDD) in some countries. Every year, 50 million children are born without the protection that iodine offers to the growing brain and body and about 18 million suffer some significant degree of mental impairment. The World Health Organization (WHO), United Nations Children's Fund (UNICEF) and non-governmental organisations assist to ensure that populations at risk have access to iodised salt. This paper will review the highlights of iodine deficiency and present the experiences in the various countries in Asia, i.e. assessments of the situation, action plans, and obstacles to implementation. PMID:19904447

  17. The importance of iodine in public health.

    PubMed

    Lazarus, John H

    2015-08-01

    Iodine (I) deficiency has been known for more than a century and is known to cause cretinism at the extreme end of the spectrum but also, importantly, impaired development and neurocognition in areas of mild deficiency. The WHO has indicated that median urinary iodine of 100-199 μg/l in a population is regarded as indicative of an adequate iodine intake. The understanding of the spectrum of iodine deficiency disorders led to the formation of The International Council for the Control of Iodine Deficiency Disorders which has promulgated the use of household iodized salt and the use of such salt in food processing and manufacture. Iodine deficiency is particularly important in pregnancy as the fetus relies on maternal thyroxine (T4) exclusively during the first 14 weeks and also throughout gestation. As this hormone is critical to brain and nervous system maturation, low maternal T4 results in low child intelligence quotient. The recommendation for I intake in pregnancy is 250 μg/day to prevent fetal and child brain function impairment. During the past 25 years, the number of countries with I deficiency has reduced to 32; these still include many European developed countries. Sustainability of adequate iodine status must be achieved by continuous monitoring and where this has not been performed I deficiency has often recurred. More randomized controlled trials of iodine supplementation in pregnancy are required in mild iodine-deficient areas to inform public health strategy and subsequent government action on suitable provision of iodine to the population at risk. PMID:25663362

  18. Production of iodine atoms by RF discharge decomposition of CF3I

    NASA Astrophysics Data System (ADS)

    Jirásek, Vít; Schmiedberger, Josef; Čenský, Miroslav; Kodymová, Jarmila

    2011-03-01

    Generation of atomic iodine by dissociation of CF3I in a RF discharge was studied experimentally in a configuration ready for direct use of the method in an oxygen-iodine laser. The discharge was ignited between coaxial electrodes with a radial distance of 3.5 mm in a flowing mixture of 0.1-0.9 mmol s-1 of CF3I and 0.5-6 mmol s-1 of buffer gas (Ar, He) at a pressure of 2-3 kPa. The discharge stability was improved by different approaches so that the discharge could be operated up to a RF source limit of 500 W without sparking. The gas leaving the discharge was injected into the subsonic or supersonic flow of N2 and the concentration of generated atomic iodine and gas temperature were measured downstream of the injection. An inhomogeneous distribution of the produced iodine atoms among the injector exit holes was observed, which was attributed to a different gas residence time corresponding to each hole. The dissociation fraction was better with pure argon as a diluting gas than in the mixture of Ar-He, although the variation in the Ar flow rate had no significant effect on CF3I dissociation. The dissociation fraction calculated from the atomic iodine concentration measured several centimetres downstream of the injection was in the range 7-30% when the absorbed electric energy ranged from 200 to 4000 J per 1 mmol of CF3I. The corresponding values of the fraction of power spent on the dissociation decreased from 8% to 2% and the energy cost for one iodine atom increased from 30 to 130 eV. Due to a possible high rate of the atomic iodine loss by recombination after leaving the discharge, these values were considered as lower limits of those achieved in the discharge.

  19. Development and Deployment of a Field Instrument for the Detection of Iodine Atoms Using Resonance Fluorescence

    NASA Astrophysics Data System (ADS)

    Bale, C. S.; Ingham, T.; Commane, R.; Heard, D. E.; Bloss, W. J.

    2007-12-01

    Recently there have been several measurements of I2, alkyl iodides (CH3I, CH2I2), iodine monoxide (IO) and OIO at sites including coastal, polar and open ocean environments. I2 and the alkyl iodides are rapidly photolysed in the atmosphere to liberate iodine atoms which may then react with ozone to form iodine monoxide (IO) radicals. Subsequent reactions of IO lead to the catalytic depletion of tropospheric ozone, affect OH:HO2 and NO:NO2 ratios, oxidise dimethyl sulphide and result in the formation of new particles. While the IO radical and its stable precursors have previously been detected and measured in the marine boundary layer, little is known about the levels of reactive inorganic halogen species, or the local distribution of iodine activity at coastal sites such as Mace Head (Ireland). We have developed an instrument which employs vacuum UV resonance-fluorescence using a microwave discharge lamp to detect atomic iodine via the (5p5) \\ 2P3/2 ← \\ 2P3/2 \\ (6s1) transition near 178 nm. The instrument is calibrated by generating a known concentration of iodine atoms from the photolysis of I2 at 185 nm. The system can be operated in two modes; either to measure ambient iodine atoms (in photochemical steady state with their precursors and IO), or to measure the total photolabile iodine loading, through broadband visible photolysis of ambient air, with detection of the iodine atoms formed. This technique allows for the in-situ measurement of the species detected, which is advantageous for gathering information about their local distribution and source. The instrument was deployed for the first time in August 2007 at Mace Head on the west coast of Ireland. We present initial results from this field trial, which represent the first observation of ambient iodine atoms in the marine atmosphere. The results will be compared with the measurements of IO obtained from the University of Leeds laser-induced fluorescence (LIF) instrument.

  20. Iodine speciation in rain, snow and aerosols

    NASA Astrophysics Data System (ADS)

    Gilfedder, B. S.; Lai, S. C.; Petri, M.; Biester, H.; Hoffmann, T.

    2008-10-01

    Iodine oxides, such as iodate, should be the only thermodynamically stable sink species for iodine in the troposphere. However, field observations have increasingly found very little iodate and significant amounts of iodide and soluble organically bound iodine (SOI) in precipitation and aerosols. The aim of this study was to investigate iodine speciation, including the organic fraction, in rain, snow, and aerosols in an attempt to further clarify aqueous phase iodine chemistry. Diurnal aerosol samples were taken with a 5 stage cascade impactor and a virtual impactor (PM2.5) from the Mace Head research station, Ireland, during summer 2006. Rain was collected from Australia, New Zealand, Patagonia, Germany, Ireland, and Switzerland and snow was obtained from Greenland, Germany, Switzerland, and New Zealand. Aerosols were extracted from the filters with water and all samples were analysed for total soluble iodine (TSI) by inductively coupled plasma mass spectrometry (ICP-MS) and iodine speciation was determined by coupling an ion chromatography unit to the ICP-MS. The median concentration of TSI in aerosols from Mace Head was 222 pmol m-3 (summed over all impactor stages) of which the majority was associated with the SOI fraction (median day: 90±4%, night: 94±2% of total iodine). Iodide exhibited higher concentrations than iodate (median 6% vs. 1.2% of total iodine), and displayed significant enrichment during the day compared to the night. Interestingly, up to 5 additional, presumably anionic iodo-organic peaks were observed in all IC-ICP-MS chromatograms, composing up to 15% of the TSI. Soluble organically bound iodine was also the dominant fraction in all rain and snow samples, with lesser amounts of iodide and iodate (iodate was particularly low in snow). Two of the same unidentified peaks found in aerosols were also observed in precipitation from both Southern and Northern Hemispheres. This suggests that these species are transferred from the aerosols into

  1. Use of iodine for water disinfection: iodine toxicity and maximum recommended dose.

    PubMed Central

    Backer, H; Hollowell, J

    2000-01-01

    Iodine is an effective, simple, and cost-efficient means of water disinfection for people who vacation, travel, or work in areas where municipal water treatment is not reliable. However, there is considerable controversy about the maximum safe iodine dose and duration of use when iodine is ingested in excess of the recommended daily dietary amount. The major health effect of concern with excess iodine ingestion is thyroid disorders, primarily hypothyroidism with or without iodine-induced goiter. A review of the human trials on the safety of iodine ingestion indicates that neither the maximum recommended dietary dose (2 mg/day) nor the maximum recommended duration of use (3 weeks) has a firm basis. Rather than a clear threshold response level or a linear and temporal dose-response relationship between iodine intake and thyroid function, there appears to be marked individual sensitivity, often resulting from unmasking of underlying thyroid disease. The use of iodine for water disinfection requires a risk-benefit decision based on iodine's benefit as a disinfectant and the changes it induces in thyroid physiology. By using appropriate disinfection techniques and monitoring thyroid function, most people can use iodine for water treatment over a prolonged period of time. PMID:10964787

  2. Iodine speciation in rain and snow: Implications for the atmospheric iodine sink

    NASA Astrophysics Data System (ADS)

    Gilfedder, Benjamin S.; Petri, Michael; Biester, Harald

    2007-04-01

    Atmospheric iodine models currently predict iodate as the only stable iodine sink species in the troposphere. However, it is shown here using ion chromatograph inductively coupled plasma-mass spectroscopy (IC-ICP-MS) that iodate is the least abundant iodine species in precipitation (rain and snow) collected from various locations in southern Germany, the Swiss Alps, and Patagonia (Chile). The majority of iodine is associated with organic compounds (average 56%) followed by iodide (average 27%). Although the exact structure of the organic fraction remains ambiguous and is probably of higher molecular weight, a smaller portion of the iodo-organic compounds are anionic (5-20% of total I). One of these anionic organo-I peaks is present in all rain and most snow chromatograms and is generally responsible for 5-18% of total iodine. This suggests a ubiquitous atmospheric iodine species. The data indicate that organic iodine compounds play an important role in the global atmospheric iodine cycle and the atmospheric iodine sink. As such, future tropospheric iodine models must consider organic-I reactions.

  3. Rechargeable Lithium-Iodine Batteries with Iodine/Nanoporous Carbon Cathode.

    PubMed

    Zhao, Qing; Lu, Yanying; Zhu, Zhiqiang; Tao, Zhanliang; Chen, Jun

    2015-09-01

    Rechargeable Li-iodine batteries are attractive electrochemical energy storage systems because iodine cathode provides the possibility of high energy density, wide abundance and low cost. However, the safety risk caused by low thermostability of iodine and the self-discharge reaction due to high solvency of iodine in aprotic solvent are target issues to be considered. Herein, we designed a room-temperature "solution-adsorption" method to prepare a thermostable iodine-carbon cathode by utilizing the strong adsorption of nanoporous carbon. Meanwhile, Li-iodine batteries constructed by the as-prepared cathode and ether-based electrolyte with the addition of LiNO3 showed negligible self-discharge reaction, high rate and long cycling performance. The reversible reactions of I2/LiI3 and LiI3/LiI in Li-iodine batteries were also proved with in situ Raman measurement. For the demonstration of application, soft-package batteries with Al-plastic film were assembled, displaying energy densities of 475 Wh/kg by mass of Li and iodine, and 136 Wh/kg by total mass of the battery. The use of nanoporous carbon to adsorb iodine at room-temperature represents a new and promising direction for realizing high-performance cathode for rechargeable Li-iodine batteries. PMID:26241461

  4. Current global iodine status and progress over the last decade towards the elimination of iodine deficiency.

    PubMed Central

    Andersson, Maria; Takkouche, Bahi; Egli, Ines; Allen, Henrietta E.; de Benoist, Bruno

    2005-01-01

    OBJECTIVE: To estimate worldwide iodine nutrition and monitor country progress towards sustained elimination of iodine deficiency disorders. METHODS: Cross-sectional data on urinary iodine (UI) and total goitre prevalence (TGP) in school-age children from 1993-2003 compiled in the WHO Global Database on Iodine Deficiency were analysed. The median UI was used to classify countries according to the public health significance of their iodine nutrition status. Estimates of the global and regional populations with insufficient iodine intake were based on the proportion of each country's population with UI below 100 microg/l. TGP was computed for trend analysis over 10 years. FINDINGS: UI data were available for 92.1% of the world's school-age children. Iodine deficiency is still a public health problem in 54 countries. A total of 36.5% (285 million) school-age children were estimated to have an insufficient iodine intake, ranging from 10.1% in the WHO Region of the Americas to 59.9% in the European Region. Extrapolating this prevalence to the general population generated an estimate of nearly two billion individuals with insufficient iodine intake. Iodine intake was more than adequate, or excessive, in 29 countries. Global TGP in the general population was 15.8%. CONCLUSION: Forty-three countries have reached optimal iodine nutrition. Strengthened UI monitoring is required to ensure that salt iodization is having the desired impact, to identify at-risk populations and to ensure sustainable prevention and control of iodine deficiency. Efforts to eliminate iodine deficiency should be maintained and expanded. PMID:16175826

  5. History of U.S. iodine fortification and supplementation.

    PubMed

    Leung, Angela M; Braverman, Lewis E; Pearce, Elizabeth N

    2012-11-01

    Iodine is a micronutrient required for thyroid hormone production. This review highlights the history of the discovery of iodine and its uses, discusses the sources of iodine nutrition, and summarizes the current recommendations for iodine intake with a focus on women of childbearing age. PMID:23201844

  6. History of U.S. Iodine Fortification and Supplementation

    PubMed Central

    Leung, Angela M.; Braverman, Lewis E.; Pearce, Elizabeth N.

    2012-01-01

    Iodine is a micronutrient required for thyroid hormone production. This review highlights the history of the discovery of iodine and its uses, discusses the sources of iodine nutrition, and summarizes the current recommendations for iodine intake with a focus on women of childbearing age. PMID:23201844

  7. Laser Fine-Adjustment Thruster For Space Vehicles

    SciTech Connect

    Rezunkov, Yu. A.; Egorov, M. S.; Repina, E. V.; Safronov, A. L.; Rebrov, S. G.

    2010-05-06

    To the present time, a few laser propulsion engine devices have been developed by using dominant mechanisms of laser propulsion. Generally these mechanisms are laser ablation, laser breakdown of gases, and laser detonation waves that are induced due to extraction of the internal energy of polymer propellants. In the paper, we consider the Aero-Space Laser Propulsion Engine (ASLPE) developed earlier, in which all of these mechanisms are realized via interaction of laser radiation with polymers both in continuous wave (CW) and in repetitively pulsed modes of laser operation. The ASLPE is considered to be exploited as a unit of a laser propulsion device being arranged onboard space vehicles moving around the Earth or in interplanetary missions and intended to correct the vehicles orbits. To produce a thrust, a power of the solar pumped lasers designed to the present time is considered in the paper. The problem of increasing the efficiency of the laser propulsion device is analyzed as applied to space missions of vehicles by optimizing the laser propulsion propellant composition.

  8. Structure of polyacetylene-iodine complexes

    NASA Astrophysics Data System (ADS)

    Murthy, N. S.; Miller, G. G.; Baughman, R. H.

    1988-08-01

    We confirm the existence of a 15 Å period in iodine-doped polyacetylene and provide a new interpretation for this key feature as part of a general model for structural changes during iodine doping. The observed diffraction intensities for different samples suggest the existence of structures with two different types of dopant-containing layers: layers obtained by complete replacement of polyacetylene chains by iodine columns (F layers) and layers obtained by replacement of every other polyacetylene chain by an iodine column (P layers). The F layers in the heavily doped complex alternate with dopant-free layers of polyacetylene chains (U layers), corresponding to a (UF)n stacking sequence. The phase obtained at a lower dopant concentration, which provides the 15 Å spacing, is attributed to a (UPUF)n stacking sequence. At still lower dopant concentrations, one obtains a (UP)n stacking sequence. This model, along with published Raman, Mössbauer, and photoelectron spectroscopy data, suggests that the ratio of I-5 to I-3 increases in going from P layers to F layers. Intense and monotonically decreasing, diffuse x-ray scattering suggests that vacancies of size ˜3 Å are present, probably in iodine columns. A diffuse reflection at 3.1 Å, observed in all iodine-doped samples, is due to an average iodine-iodine distance in disordered columnar arrays. On the other hand, ordered arrays of iodine columns in oriented samples give rise to sharp meridional reflections. All ten observed reflections (down to 1.17 Å) in one sample could be indexed based on a 33.8 Å repeat corresponding to (-I-3-I-5-I-3-)n arrays. The observed diffraction pattern was calculated from this model without using any freely adjustable parameters.

  9. Computation of iodine species concentrations in water

    NASA Technical Reports Server (NTRS)

    Schultz, John R.; Mudgett, Paul D.; Flanagan, David T.; Sauer, Richard L.

    1994-01-01

    During an evaluation of the use of iodine as a water disinfectant and the development of methods for measuring various iodine species in water onboard Space Freedom, it became necessary to compute the concentration of the various species based on equilibrium principles alone. Of particular concern was the case when various amounts of iodine, iodide, strong acid, and strong base are added to water. Such solutions can be used to evaluate the performance of various monitoring methods being considered. The authors of this paper present an overview of aqueous iodine chemistry, a set of nonlinear equations which can be used to model the above case, and a computer program for solving this system of equations using the Newton-Raphson method. The program was validated by comparing results over a range of concentrations and pH values with those previously presented by Gottardi for a given pH. Use of this program indicated that there are multiple roots to many cases and selecting an appropriate initial guess is important. Comparison of program results with laboratory results for the case when only iodine is added to water indicates the program gives high pH values for the iodine concentrations normally used for water disinfection. Extending the model to include the effects of iodate formation results in the computer pH values being closer to those observed, but the model with iodate does not agree well for the case in which base is added in addition to iodine to raise the pH. Potential explanations include failure to obtain equilibrium conditions in the lab, inaccuracies in published values for the equilibrium constants, and inadequate model of iodine chemistry and/or the lack of adequate analytical methods for measuring the various iodine species in water.

  10. Method and apparatus for removing iodine from a nuclear reactor coolant

    DOEpatents

    Cooper, Martin H.

    1980-01-01

    A method and apparatus for removing iodine-131 and iodine-125 from a liquid sodium reactor coolant. Non-radioactive iodine is dissolved in hot liquid sodium to increase the total iodine concentration. Subsequent precipitation of the iodine in a cold trap removes both the radioactive iodine isotopes as well as the non-radioactive iodine.

  11. Effect of chronic douching with polyvinylpyrrolidone-iodine on iodine absorption and thyroid function

    SciTech Connect

    Safran, M.; Braverman, L.E.

    1982-07-01

    Daily vaginal douching with polyvinylpyrrolidone-iodine in 12 euthyroid volunteers for 14 days resulted in a significant increase in serum total iodine concentration and urine iodine excretion. The increase in serum total iodine was associated with a marked decrease in 24-hour /sup 123/I uptake by the thyroid and a small but significant increase in serum thyrotropin (TSH) concentration. However, values for serum TSH never rose above the normal range. No significant changes in serum thyroxine (T4), free T4 index (FTI), or triiodothyronine concentrations were observed, although serum T4 and FTI did decrease slightly during treatment. The findings suggest that iodine is absorbed across the vaginal mucosa and that the subsequent increase in serum total iodine does induce subtle increases in serum TSH concentration. There was no evidence, however, of overt hypothyroidism in these euthyroid women.

  12. Method for immobilizing radioactive iodine

    DOEpatents

    Babad, Harry; Strachan, Denis M.

    1980-01-01

    Radioactive iodine, present as alkali metal iodides or iodates in an aqueous solution, is incorporated into an inert solid material for long-term storage by adding to the solution a stoichiometric amount with respect to the formation of a sodalite (3M.sub.2 O.3Al.sub.2 O.sub.3. 6SiO.sub.2.2MX, where M=alkali metal; X=I.sup.- or IO.sub.3.sup.-) of an alkali metal, alumina and silica, stirring the solution to form a homogeneous mixture, drying the mixture to form a powder, compacting and sintering the compacted powder at 1073 to 1373 K (800.degree. to 1100.degree. C.) for a time sufficient to form sodalite.

  13. Iodine binding to humic acid.

    PubMed

    Bowley, H E; Young, S D; Ander, E L; Crout, N M J; Watts, M J; Bailey, E H

    2016-08-01

    The rate of reactions between humic acid (HA) and iodide (I(-)) and iodate (IO3(-)) have been investigated in suspensions spiked with (129)I at concentrations of 22, 44 and 88 μg L(-1) and stored at 10 °C. Changes in the speciation of (129)I(-), (129)IO3(-) and mixed ((129)I(-) + (129)IO3(-)) spikes were monitored over 77 days using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). In suspensions spiked with (129)I(-) 25% of the added I(-) was transformed into organic iodine (Org-(129)I) within 77 days and there was no evidence of (129)IO3(-) formation. By contrast, rapid loss of (129)IO3(-) and increase in both (129)I(-) and Org-(129)I was observed in (129)IO3(-)-spiked suspensions. However, the rate of Org-(129)I production was greater in mixed systems compared to (129)IO3(-)-spiked suspensions with the same total (129)I concentration, possibly indicating IO3(-)I(-) redox coupling. Size exclusion chromatography (SEC) demonstrated that Org-(129)I was present in both high and low molecular weight fractions of the HA although a slight preference to bond with the lower molecular weight fractions was observed indicating that, after 77 days, the spiked isotope had not fully mixed with the native (127)I pool. Iodine transformations were modelled using first order rate equations and fitted rate coefficients determined. However, extrapolation of the model to 250 days indicated that a pseudo-steady state would be attained after ∼200 days but that the proportion of (129)I incorporated into HA was less than that of (127)I indicating the presence of a recalcitrant pool of (127)I that was unavailable for isotopic mixing. PMID:27231879

  14. Probing starch-iodine interaction by atomic force microscopy.

    PubMed

    Du, Xiongwei; An, Hongjie; Liu, Zhongdong; Yang, Hongshun; Wei, Lijuan

    2014-01-01

    We explored the interaction of iodine with three crystalline type starches, corn, potato, and sweet potato starches using atomic force microscopy. Results revealed that starch molecules aggregated through interaction with iodine solution as well as iodine vapor. Detailed fine structures such as networks, chains, and super-helical structures were found in iodide solution tests. The nanostructures formed due to iodine adsorption could help to understand the formation and properties of the starch-iodine complex. PMID:24338992

  15. A model to secure a stable iodine concentration in milk

    PubMed Central

    Trøan, Gisken; Dahl, Lisbeth; Meltzer, Helle Margrete; Abel, Marianne Hope; Indahl, Ulf Geir; Haug, Anna; Prestløkken, Egil

    2015-01-01

    Background Dairy products account for approximately 60% of the iodine intake in the Norwegian population. The iodine concentration in cow's milk varies considerably, depending on feeding practices, season, and amount of iodine and rapeseed products in cow fodder. The variation in iodine in milk affects the risk of iodine deficiency or excess in the population. Objective The first goal of this study was to develop a model to predict the iodine concentration in milk based on the concentration of iodine and rapeseed or glucosinolate in feed, as a tool to securing stable iodine concentration in milk. A second aim was to estimate the impact of different iodine levels in milk on iodine nutrition in the Norwegian population. Design Two models were developed on the basis of results from eight published and two unpublished studies from the past 20 years. The models were based on different iodine concentrations in the fodder combined with either glucosinolate (Model 1) or rapeseed cake/meal (Model 2). To illustrate the impact of different iodine concentrations in milk on iodine intake, we simulated the iodine contribution from dairy products in different population groups based on food intake data in the most recent dietary surveys in Norway. Results The models developed could predict iodine concentration in milk. Cross-validation showed good fit and confirmed the explanatory power of the models. Our calculations showed that dairy products with current iodine level in milk (200 µg/kg) cover 68, 49, 108 and 56% of the daily iodine requirements for men, women, 2-year-old children, and pregnant women, respectively. Conclusions Securing a stable level of iodine in milk by adjusting iodine concentration in different cow feeds is thus important for preventing excess intake in small children and iodine deficiency in pregnant and non-pregnant women. PMID:26689316

  16. [Iodine-induced hyperthyroidism after cadexomer iodine treatment of leg ulcers].

    PubMed

    Michanek, A; Hansson, C; Berg, G; Månesköld-Claes, A

    1998-12-01

    The article consists in two case reports of eldery patients who developed hyperthyroidism after cadexomer iodine treatment of small leg ulcers. The first was an 87-year-old woman who developed anxiety, hoarseness and tachycardia after five months treatment of a 12 cm2 leg ulcer with 350 g cadexomer iodine. Her serum level of free thyroxine (FT4) was 23.1 pmol/l (normal range, 11.7-28.0), and that of thyroid-stimulating hormone (TSH) 0.01 mIU/l (normal range, 0.1-3.0). She had had a nodular goitre for thirty years. The second was an 86- year-old woman who developed depression and confusion after three months' treatment of an 8 cm2 leg ulcer with 170 g cadexomere iodine. Her serum level of FT4 was 30.0 pmol/l, and that of TSH 0.005 mIU/l. Both patients underwent Tc99m pertechnetate scanning and iodine uptake measurement with a view to treating the hyperthyroidism with radio-iodine. However, as iodine uptake was inhibited in both cases, radio-iodine treatment was impossible, and symptomatic treatment and antithyroid drugs had to be used. Thus, it is concluded that topical treatment with cadexomer iodine can induce hyperthyroidism difficult to manage clinically as the treatment options are limited, which should be borne in mind when cadexomer iodine treatment is considered. PMID:9889495

  17. Iodine content in bread, milk and the retention of inherent iodine in commonly used Indian recipes.

    PubMed

    Longvah, T; Toteja, G S; Upadhyay, A

    2013-01-15

    Iodine deficiency disorders (IDD) is still a major public health problem and iodized salt remains the most effective means to control IDD in India. Few reports indicate that vegans have inadequate iodine intake while at the same time concerns are being raised on the implementation of universal salt iodization in the country. Therefore, we investigated the iodine content in bread, milk and commonly used Indian recipes prepared without iodized salt and the retention of inherent iodine therein. Results showed considerable iodine content in bread (25 μg/100g) and milk (303 μg/L) as a positive fallout of universal salt iodization. Iodine content in 38 vegetarian recipes prepared without iodized salt was very low (2.9 ± 2.4 μg/100g). Retention of inherent iodine (65.6 ± 15.4%) and iodine from iodized salt (76.7 ± 10.3%) in the same recipes was comparable. Thus, universal salt iodization programme remains the single most important source of dietary iodine for the Indian population. PMID:23122074

  18. Radioactive Iodine (I-131) Therapy for Hyperthyroidism

    MedlinePlus

    ... Iodine (I-131) Therapy Radioiodine therapy is a nuclear medicine treatment for an overactive thyroid, a condition ... locally overactive in producing too much thyroid hormone. Nuclear medicine is a branch of medical imaging that ...

  19. Teaching the Rovibronic Spectroscopy of Molecular Iodine

    ERIC Educational Resources Information Center

    Williamson, J. Charles

    2007-01-01

    The rovibronic spectroscopy of molecular iodine provides a clearer understanding of the electronic potential parameters of various systems to the undergraduate students. The technique also helps them to test the various other quantum mechanical concepts.

  20. The Electronic Spectrum of Iodine Revisited.

    ERIC Educational Resources Information Center

    McNaught, Ian J.

    1980-01-01

    Presents equations and techniques for calculating and interpreting many of the spectroscopically important parameters associated with the ground and second excited states of the iodine molecule. (Author/CS)

  1. Tositumomab and Iodine I 131 Tositumomab

    Cancer.gov

    This page contains brief information about tositumomab and iodine I 131 tositumomab and a collection of links to more information about the use of this drug combination, research results, and ongoing clinical trials.

  2. Regenerable Iodine Water-Disinfection System

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

    1994-01-01

    Iodinated resin bed for disinfecting water regenerated to extend useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle manually controlled readily automated to start and stop according to signals from concentration sensors. Further benefit of regeneration is bed provides highly concentrated biocide source when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

  3. Iodine supplementation and the prevention of cretinism.

    PubMed

    Dunn, J T

    1993-03-15

    Normal development of the CNS requires adequate thyroid hormone exposure. Since iodine is an essential component of the thyroid hormone molecule, its deficiency during fetal development can cause hypothyroidism and irreversible mental retardation. The full-blown syndrome, called cretinism, includes deaf-mutism, short stature, spasticity, and profound mental retardation. The clinical spectrum can vary in degree and combination of these features. Screening programs in iodine-deficient countries show that up to 10% of neonates have elevated serum TSH levels, putting them at theoretical risk for permanent brain damage. About one billion people worldwide risk the consequences of iodine deficiency, all of which can be prevented by adequate maternal and infant iodine nutrition. Iodized salt is usually the preferred prophylactic vehicle, but iodized vegetable oil, iodized water, and iodine tablets are also occasionally used. The United Nations and the heads of state of most countries have pledged the virtual elimination of iodine deficiency by the year 2000. This goal is technically feasible if pursued with sufficient vigor and resources. PMID:8494259

  4. Modern and past volcanic degassing of iodine

    NASA Astrophysics Data System (ADS)

    Bureau, H.; Auzende, A.-L.; Marocchi, M.; Raepsaet, C.; Munsch, P.; Testemale, D.; Mézouar, M.; Kubsky, S.; Carrière, M.; Ricolleau, A.; Fiquet, G.

    2016-01-01

    We have monitored iodine degassing from a melt to a water vapor during decompression (i.e. magma ascent). Experiments have been performed by combining diamond anvil cells experiments with synchrotron X-rays fluorescence analysis. Partition coefficients DIfluid/melt measured for a pressure and temperature range of 0.1-1.8 GPa and 500-900 °C, range from 41 to 1.92, values for room conditions DIfluid/glass (quenched samples) are equal to or higher than 350. We show that iodine degassing with water is earlier and much more efficient than for lighter halogen elements, Cl and Br. Iodine is totally degassed from the silicate melt at room conditions. By applying these results to modern volcanology, we calculate an annual iodine flux for subduction related volcanism of 0.16-2.4 kt yr-1. We suggest that the natural iodine degassing may be underestimated, having possible consequences on the Earth's ozone destruction cycle. By applying this results to the Early Earth, we propose a process that may explain the contrasted signature of I, Br and Cl, strongly depleted in the bulk silicate Earth, the most depleted being iodine, whereas fluorine is almost enriched. The Earth may have lost heavy halogen elements during an early water degassing process from the magma ocean.

  5. Electron microscopy of low iodinated thyroglobulin molecules.

    PubMed

    Berg, G; Ekholm, R

    1975-04-29

    Thyroglobulin molecules were studied in the electron microscope with negative staining technique. In a first series of experiments samples of thyroglobulin varying in iodine content from 0.5 to 0.03% were prepared from the thyroids of mice and rats kept on iodine-poor diets. All samples contained thyroglobulin molecules of the normal ovoid shape, not deviating in size or shape from molecules obtained from normal thyroids. However, in addition, another type of molecule having a cylindrical shape was observed in all samples. The proportion of these cylindrical molecules increased from a few per cent in the moderately iodine-poor thyroglobulin samples to more than 80% in the highly iodine-deficient thyroglobulin (0.03%). In a second series of experiments extremely iodine-poor thyroglobulin (smaller than 0.005%) was obtained from propylthiouracil-treated rats. In these preparations practically all molecules had a cylindrical shape. These samples also contained smaller particles interpreted to be dissociation products. The cylindrical molecules were of two types, one appearing compact and measuring 250 times 135 A (length times diameter) and the other appearing porous and having a length of 145 and a diameter of 205 A. It is concluded that the cylindrical molecules represent non- or low-iodinated thyroglobulin and it is suggested that the porous cylindrical molecule is an unfolded form of the compact cylinder. PMID:1138879

  6. Proposed ground-based incoherent Doppler lidar with iodine filter discriminator for atmospheric wind profiling

    SciTech Connect

    Liu, Z.S.; Chen, W.B.; Hair, J.W.; She, C.Y.

    1996-12-31

    A new incoherent lidar for measuring atmospheric wind using iodine molecular filter is proposed. A unique feature of the proposed lidar lies in its capability for simultaneous measurement of aerosol mixing ratio, with which the radial wind can be determined uniquely from lidar return. A preliminary laboratory experiment using a dye laser at 589 nm and a rotating wheel has been performed demonstrating the feasibility of the proposed wind measurement.

  7. Effect of iodine disinfection products on higher plants

    NASA Technical Reports Server (NTRS)

    Janik, D.; Macler, B.; Macelroy, R. D.; Thorstenson, Y.; Sauer, R.

    1989-01-01

    Iodine is used to disinfect potable water on United States spacecraft. Iodinated potable water will likely be used to grow plants in space. Little is known about the effects of iodine disinfection products on plants. Seeds of select higher plants were germinated in water iodinated using the Shuttle Microbial Check Valve, and water to which measured amounts of iodine was added. Percent germination was decreased in seeds of most species germinated in iodinated water. Beans were most affected. Germination rates, determined from germination half-times, were decreased for beans germinated in iodinated water, and water to which iodide was added. Development was retarded and rootlets were conspicuously absent in bean and several other plant species germinated in iodinated water. Iodide alone did not elicit these responses. Clearly iodine disinfection products can affect higher plants. These effects must be carefully considered for plant experimentation and cultivation in space, and in design and testing of closed environmental life support systems.

  8. Iodine derivatives of chemically modified gum Arabic microspheres.

    PubMed

    Ganie, Showkat A; Ali, Akbar; Mazumdar, Nasreen

    2015-09-20

    Acetylated gum Arabic (AGA) derivatives with different degrees of substitution (DS 0.97-2.74) were synthesized using acetyl chloride and a base under varying reaction conditions. The AGA derivatives were obtained in the form of microspheres and thereafter stable iodine products were prepared by doping the microspheres with an iodinating agent, iodine monochloride (ICl). The reaction between electrophilic iodine and polar carbonyl groups was studied by FT-IR, (1)H-NMR, and UV-VIS spectroscopies. The products were also characterized by DSC, TGA and SEM studies. The incorporated iodine was released in aqueous medium as iodide ions (I(-)). A reaction scheme has been proposed for the iodination and de-iodination of the gum derivatives. This work suggests that the iodine derivatives of modified gum Arabic could be used as a source of iodide ions which is the nutritional form of iodine. PMID:26050909

  9. Thyroid and iodine nutritional status: a UK perspective.

    PubMed

    Vanderpump, Mark

    2014-12-01

    Iodine is an essential component of the thyroid hormones, which play a crucial role in brain and neurological development. At least one-third of the world's population is estimated to be iodine deficient predominantly in developing countries. Recently concern had also been expressed about the iodine status in industrialised countries such as the UK. A recent survey of the UK iodine status found that that more than two-thirds of schoolgirls aged 14-15 years were iodine deficient due to the reduced milk intake. Maternal iodine deficiency in pregnancy is correlated with cognitive outcomes such as intelligence quotient and reading ability in offspring. No randomised trial data exist for iodine supplementation in mild-moderate iodine-deficient pregnant women. It is possible to combine population interventions to reduce population salt intake with salt iodisation programmes in order to maintain adequate levels of iodine nutrition. PMID:25468924

  10. Mixed-layered bismuth-oxygen-iodine materials for capture and waste disposal of radioactive iodine

    DOEpatents

    Krumhansl, James L; Nenoff, Tina M

    2013-02-26

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  11. Mixed-layered bismuth--oxygen--iodine materials for capture and waste disposal of radioactive iodine

    DOEpatents

    Krumhansl, James L; Nenoff, Tina M

    2015-01-06

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  12. Iodine-129 Dose in LLW Disposal Facility Performance Assessments

    SciTech Connect

    Wilhite, E.L.

    1999-10-15

    Iodine-129 has the lowest Performance Assessment derived inventory limit in SRS disposal facilities. Because iodine is concentrated in the body to one organ, the thyroid, it has been thought that dilution with stable iodine would reduce the dose effects of 129I.Examination of the dose model used to establish the Dose conversion factor for 129I shows that, at the levels considered in performance assessments of low-level waste disposal facilities, the calculated 129I dose already accounts for ingestion of stable iodine. At higher than normal iodine ingestion rates, the uptake of iodine by the thyroid itself decrease, which effectively cancels out the isotopic dilution effect.

  13. [Application of iodine metabolism analysis methods in thyroid diseases].

    PubMed

    Han, Jian-hua; Qiu, Ling

    2013-08-01

    The main physiological role of iodine in the body is to synthesize thyroid hormone. Both iodine deficiency and iodine excess can lead to severe thyroid diseases. While its role in thyroid diseases has increasingly been recognized, few relevant platforms and techniques for iodine detection have been available in China. This paper summarizes the advantages and disadvantages of currently iodine detection methods including direct titration, arsenic cerium catalytic spectrophotometry, chromatography with pulsed amperometry, colorimetry based on automatic biochemistry, inductively coupled plasma mass spectrometry, so as to optimize the iodine nutrition for patients with thyroid diseases. PMID:23987480

  14. Effects of increased iodine intake on thyroid disorders.

    PubMed

    Sun, Xin; Shan, Zhongyan; Teng, Weiping

    2014-09-01

    Iodine is a micronutrient essential for the production of thyroid hormones. Iodine deficiency is the most common cause of preventable mental impairment worldwide. Universal salt iodization (USI) has been introduced in many countries as a cost-effective and sustainable way to eliminate iodine deficiency disorders for more than 25 years. Currently, the relationship between USI and iodine excess has attracted more attention. Iodine excess can lead to hypothyroidism and autoimmune thyroiditis, especially for susceptible populations with recurring thyroid disease, the elderly, fetuses, and neonates. Nationwide USI was introduced in China in 1996. This review focused on the effects of iodine excess worldwide and particularly in China. PMID:25309781

  15. Exploding conducting film laser pumping apparatus

    DOEpatents

    Ware, Kenneth D.; Jones, Claude R.

    1986-01-01

    Exploding conducting film laser optical pumping apparatus. The 342-nm molecular iodine and the 1.315-.mu.m atomic iodine lasers have been optically pumped by intense light from exploding-metal-film discharges. Brightness temperatures for the exploding-film discharges were approximately 25,000 K. Although lower output energies were achieved for such discharges when compared to exploding-wire techniques, the larger surface area and smaller inductance inherent in the exploding-film should lead to improved efficiency for optically-pumped gas lasers.

  16. A Solar-pumped Fluorescence Model for Line-by-line Emission Intensities in the B–X, A–X, and X–X Band Systems of 12C14N

    NASA Astrophysics Data System (ADS)

    Paganini, L.; Mumma, M. J.

    2016-09-01

    We present a new quantitative model for detailed solar-pumped fluorescent emission of the main isotopologue of CN. The derived fluorescence efficiencies permit estimation and interpretation of ro-vibrational infrared line intensities of CN in exospheres exposed to solar (or stellar) radiation. Our g-factors are applicable to astronomical observations of CN extending from infrared to optical wavelengths, and we compare them with previous calculations in the literature. The new model enables extraction of rotational temperature, column abundance, and production rate from astronomical observations of CN in the inner coma of comets. Our model accounts for excitation and de-excitation of rotational levels in the ground vibrational state by collisions, solar excitation to the {A}2{{{\\Pi }}}{{i}} and {B}2{{{Σ }}}+ electronically excited states followed by cascade to ro-vibrational levels of {X}2{{{Σ }}}+, and direct solar infrared pumping of ro-vibrational levels in the {X}2{{{Σ }}}+ state. The model uses advanced solar spectra acquired at high spectral resolution at the relevant infrared and optical wavelengths and considers the heliocentric radial velocity of the comet (the Swings effect) when assessing the exciting solar flux for a given transition. We present model predictions for the variation of fluorescence rates with rotational temperature and heliocentric radial velocity. Furthermore, we test our fluorescence model by comparing predicted and measured line-by-line intensities for {X}2{{{Σ }}}+ (1–0) in comet C/2014 Q2 (Lovejoy), thereby identifying multiple emission lines observed at IR wavelengths.

  17. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine....

  18. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine....

  19. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine....

  20. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine....

  1. 40 CFR 415.430 - Applicability; description of the iodine production subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... iodine production subcategory. 415.430 Section 415.430 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Iodine Production Subcategory § 415.430 Applicability; description of the iodine production... iodine....

  2. Theoretical studies of solar lasers and converters

    NASA Technical Reports Server (NTRS)

    Heinbockel, John H.

    1990-01-01

    The research described consisted of developing and refining the continuous flow laser model program including the creation of a working model. The mathematical development of a two pass amplifier for an iodine laser is summarized. A computer program for the amplifier's simulation is included with output from the simulation model.

  3. First application of an online method for quantification of maritime molecular iodine and hypoiodic acid in maritime aerosol during PEGASO cruise

    NASA Astrophysics Data System (ADS)

    Götz, Sven; Dall'Osto, Manuel; Simó, Rafel; Hoffmann, Thosten

    2015-04-01

    The atmospheric chemistry of iodine is important in multiple ways. The focus lies on the ability to influence the oxidizing capacity of the atmosphere, i.e. by destruction of ozone, and the formation of iodine oxide particles (IOP), i.e. the influence on condensation nuclei (CCN). Using a variation of techniques, like differential optical absorption spectroscopy (DOAS), laser-induced fluorescence (LIF), inductively coupled plasma mass spectrometry (ICP-MS) and atmospheric pressure chemical ionization with tandem mass spectrometry (APCI-MS/MS), the reactive iodine species of atomic iodine (I), molecular iodine (I2), iodine monoxide (IO) and iodine dioxide (OIO) have all been detected in the atmosphere from Antarctica to the equatorial marine boundary layer (MBL). In the past few years there have been active research on IO, especially after revealing significant levels in open ocean measurements, and higher iodine oxides. In addition to atmospheric measurements, significant developments in laboratory kinetics, photochemistry and heterogeneous chemistry of iodine species have been accomplished. [1] Here we introduce the first field application of an online-method for detecting gaseous molecular iodine and HOI, which is a further development of a technique [2] based on selective photolytic dissociation, followed by oxidization and particle formation of iodine compounds. The particles are than size-segregated and detected by a scanning mobility particle sizer (SMPS) system. Initial IOP forming is performed in a reaction chamber providing specific wavelengths according to corresponding bond dissociation thresholds. Additionally offline sampling of iodine and iodine containing interhalogenes with coated diffusion denuders [3] were carried out throughout the cruise to compare both methods after analysis with GC/MS. Furthermore filter samples were taken to perform non-target analysis of organic compounds by UHPLC/ESI(+/-)-HR-MS. Preliminary results of iodine related

  4. [Iodine and thyroid: what a clinic should know].

    PubMed

    Santana Lopes, Maria; Jácome de Castro, João; Marcelino, Mafalda; Oliveira, Maria João; Carrilho, Francisco; Limbert, Edward

    2012-01-01

    The World Health Organization considers iodine deficiency as a major worldwide cause of mental and development diseases, estimating that about 13% of the world population is affected by diseases caused by iodine deficiency. Iodine is a trace element necessary for the synthesis of thyroid hormones which, since it cannot be formed by the organism, must be taken regularly with food. Fish and shellfish are generally a good source, because the ocean contains a considerable amount of iodine. On the contrary, plants which grow in iodine-deficient soils are poor in this element, as well as meat and other animal products fed in plants low in iodine. Salt is the best way for iodine supplementation. Cooking the food with iodized salt is a desirable practice because it guarantees the presence of this element. There are also other methods to provide iodine to the general population, such as adding iodine to drinking water or taking supplements of iodine. In pregnancy is recommended iodine supplementation, except in patients with known thyroid disorders. Iodine is an essential component of thyroid hormones (T4 and T3). Inadequate iodine intake leads to inadequate thyroid hormone production. The most important consequences of iodine deficiency, in the general population are goiter and hypothyroidism, and in the severe cases, mental retardation, cretinism and increased neo-natal and infant mortality. The International Council for the Control of Iodine Deficiency Disorders (ICCIDD) formed in 1985, with the only aim of achieving optimal iodine nutrition in the world, in cooperation with UNICEF and WHO. In Portugal, recent studies show significant deficiencies in pregnancy and The Portuguese Society of Endocrinology Diabetes and Metabolism, in partnership with General Directorate of Health, proposed an iodine supplementation during pregnancy with 150-200µg/day. PMID:23069238

  5. Iodine Supplementation: Usage "with a Grain of Salt".

    PubMed

    Prete, Alessandro; Paragliola, Rosa Maria; Corsello, Salvatore Maria

    2015-01-01

    Iodine supplementation through salt iodization is a worldwide, effective strategy for preventing iodine deficiency-related problems. Its safety and efficacy profile has been extensively investigated, and benefits far outweigh the potential iodine-induced risks. Moreover, iodine supplementation during pregnancy in order to avoid brain damage in the newborn is considered a mainstay of preventive medicine. Exposure to high amounts of iodine is actually well tolerated in most cases and can be unrecognized. Nevertheless, at-risk individuals may develop thyroid dysfunction even when they are exposed to increases in iodine intake universally considered as safe. Iodine-induced thyroid disorders include thyroid autoimmunity, thyrotoxicosis, iodine-induced goiter, and hypothyroidism. Moreover, a relationship between iodine intake and histotype distribution of differentiated thyroid cancer has been observed, with a progressive shift from follicular to papillary thyroid cancer. To date, evaluating iodine status in a clinical setting has limitations, and assessing the actual risk for each individual can be challenging, since it is influenced by personal history, genetics, and environmental factors. In conclusion, iodine supplementation programs need to be continued and strengthened, but iodine should be used "with a grain of salt," because a growing number of susceptible individuals will be exposed to the risk of developing iodine-induced thyroid disorders. PMID:25873950

  6. Iodine Supplementation in Pregnancy and the Dilemma of Ambiguous Recommendations.

    PubMed

    Andersen, Stine Linding; Laurberg, Peter

    2016-03-01

    Iodine requirements are increased during pregnancy, predominantly caused by an increase in renal iodide clearance and in the use of iodine for thyroid hormone production. Because iodine deficiency (ID) in pregnancy may be associated with neurodevelopmental deficits in the offspring, a pertinent question is at what level of iodine intake pregnant women should be advised to take iodine-containing supplements. The consensus reached by the WHO/UNICEF/ICCIDD in 2007 was that pregnant women should not be recommended to take iodine-containing supplements if the population in general had been iodine sufficient for at least 2 years. However, guidance on this differs between scientific societies. This review discusses iodine supplementation in pregnancy. Based on current evidence, the recommendations given by WHO/UNICEF/ICCIDD in 2007 provide a valid guidance on the use of iodine supplements in pregnant women. Women living in a population with a median urinary iodine concentration (UIC) at or above 100 µg/l are not in need of iodine supplementation in pregnancy. On the other hand, if the population median UIC is below 100 µg/l, pregnant women should take iodine-containing supplements until the population in general has been iodine sufficient for at least 2 years by way of universal salt iodization. PMID:27099837

  7. Iodine Supplementation in Pregnancy and the Dilemma of Ambiguous Recommendations

    PubMed Central

    Andersen, Stine Linding; Laurberg, Peter

    2016-01-01

    Iodine requirements are increased during pregnancy, predominantly caused by an increase in renal iodide clearance and in the use of iodine for thyroid hormone production. Because iodine deficiency (ID) in pregnancy may be associated with neurodevelopmental deficits in the offspring, a pertinent question is at what level of iodine intake pregnant women should be advised to take iodine-containing supplements. The consensus reached by the WHO/UNICEF/ICCIDD in 2007 was that pregnant women should not be recommended to take iodine-containing supplements if the population in general had been iodine sufficient for at least 2 years. However, guidance on this differs between scientific societies. This review discusses iodine supplementation in pregnancy. Based on current evidence, the recommendations given by WHO/UNICEF/ICCIDD in 2007 provide a valid guidance on the use of iodine supplements in pregnant women. Women living in a population with a median urinary iodine concentration (UIC) at or above 100 µg/l are not in need of iodine supplementation in pregnancy. On the other hand, if the population median UIC is below 100 µg/l, pregnant women should take iodine-containing supplements until the population in general has been iodine sufficient for at least 2 years by way of universal salt iodization. PMID:27099837

  8. Technical digest of ICALEO, 84

    SciTech Connect

    Not Available

    1984-01-01

    This book presents the papers given at a symposium on laser welding and laser spectroscopy. Topics considered at the symposium included dimensional modeling of conduction-mode laser welding, the effect of angle of incidence on plasmas generated during laser welding, metal mirrors for carbon dioxide lasers, zinc selenide optics, potassium chloride optics, laser beam diagnostics for metalworking applications, the photochemistry of alkali metal vapor lasers, solar pumped iodine amplifiers, multiphoton ionization and excitation of fluoranthene and benzene, fluorescence spectroscopy, laser Doppler anemometer measurements in internal combustion engines, coherent anti-stokes Raman scattering, and pulsed-laser techniques for the temperature measurement of rotating surfaces.

  9. A solar simulator-pumped gas laser for the direct conversion of solar energy

    NASA Technical Reports Server (NTRS)

    Weaver, W. R.; Lee, J. H.

    1981-01-01

    Most proposed space power systems are comprised of three general stages, including the collection of the solar radiation, the conversion to a useful form, and the transmission to a receiver. The solar-pumped laser, however, effectively eliminates the middle stage and offers direct photon-to-photon conversion. The laser is especially suited for space-to-space power transmission and communication because of minimal beam spread, low power loss over large distances, and extreme energy densities. A description is presented of the first gas laser pumped by a solar simulator that is scalable to high power levels. The lasant is an iodide C3F7I that as a laser-fusion driver has produced terawatt peak power levels.

  10. Surface concentration dependent structures of iodine on Pd(110)

    NASA Astrophysics Data System (ADS)

    Göthelid, Mats; Tymczenko, Michael; Chow, Winnie; Ahmadi, Sareh; Yu, Shun; Bruhn, Benjamin; Stoltz, Dunja; von Schenck, Henrik; Weissenrieder, Jonas; Sun, Chenghua

    2012-11-01

    We use photoelectron spectroscopy, low energy electron diffraction, scanning tunneling microscopy, and density functional theory to investigate coverage dependent iodine structures on Pd(110). At 0.5 ML (monolayer), a c(2 × 2) structure is formed with iodine occupying the four-fold hollow site. At increasing coverage, the iodine layer compresses into a quasi-hexagonal structure at 2/3 ML, with iodine occupying both hollow and long bridge positions. There is a substantial difference in electronic structure between these two iodine sites, with a higher electron density on the bridge bonded iodine. In addition, numerous positively charged iodine near vacancies are found along the domain walls. These different electronic structures will have an impact on the chemical properties of these iodine atoms within the layer.

  11. Noise-immune laser receiver - transmitters with the quantum sensitivity limit

    SciTech Connect

    Kutaev, Yu F; Mankevich, S K; Nosach, O Yu; Orlov, E P

    2009-11-30

    We consider the operation principles of noise-immune near-IR receiver - transmitters with the quantum sensitivity limit, in which active quantum filters based on iodine photodissociation quantum amplifiers and iodine lasers are used. The possible applications of these devices in laser location, laser space communication, for the search for signals from extraterrestrial civilisations and sending signals to extraterrestrial civilisations are discussed. (invited paper)

  12. Iodine Propulsion Advantages for Low Cost Mission Applications and the Iodine Satellite (ISAT) Technology Demonstration

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Schumacher, Daniel M.

    2015-01-01

    The NASA Marshall Space Flight Center Science and Technology Office is continuously exploring technology options to increase performance or reduce cost and risk to future NASA missions including science and exploration. Electric propulsion is a prevalent technology known to reduce mission costs by reduction in launch costs and spacecraft mass through increased post launch propulsion performance. The exploration of alternative propellants for electric propulsion continues to be of interest to the community. Iodine testing has demonstrated comparable performance to xenon. However, iodine has a higher storage density resulting in higher ?V capability for volume constrained systems. Iodine's unique properties also allow for unpressurized storage yet sublimation with minimal power requirements to produce required gas flow rates. These characteristics make iodine an ideal propellant for secondary spacecraft. A range of mission have been evaluated with a focus on low-cost applications. Results highlight the potential for significant cost reduction over state of the art. Based on the potential, NASA has been developing the iodine Satellite for a near-term iodine Hall propulsion technology demonstration. Mission applications and progress of the iodine Satellite project are presented.

  13. The Ozone-Iodine-Chlorate Clock Reaction

    PubMed Central

    Sant'Anna, Rafaela T. P.; Monteiro, Emily V.; Pereira, Juliano R. T.; Faria, Roberto B.

    2013-01-01

    This work presents a new clock reaction based on ozone, iodine, and chlorate that differs from the known chlorate-iodine clock reaction because it does not require UV light. The induction period for this new clock reaction depends inversely on the initial concentrations of ozone, chlorate, and perchloric acid but is independent of the initial iodine concentration. The proposed mechanism considers the reaction of ozone and iodide to form HOI, which is a key species for producing non-linear autocatalytic behavior. The novelty of this system lies in the presence of ozone, whose participation has never been observed in complex systems such as clock or oscillating reactions. Thus, the autocatalysis demonstrated in this new clock reaction should open the possibility for a new family of oscillating reactions. PMID:24386257

  14. [Iodine deficiency in infancy - a risk for cognitive development].

    PubMed

    Remer, T; Johner, S A; Gärtner, R; Thamm, M; Kriener, E

    2010-08-01

    Severe iodine deficiency during pregnancy seriously influences fetal brain development and in the worst case induces cretinism. Recent studies have shown that even a mild iodine deficiency during pregnancy and during the first years of life adversely affects brain development. The World Health Organisation (WHO) considers iodine deficiency as the most common preventable cause of early childhood mental deficiency. In this context, the insufficient production of the four iodine atoms containing thyroxine seems to play a causal role, i. e., due to the iodine substrate deficiency the neuronally particularly relevant free-thyroxine level falls. Due to the very limited iodine storage capacity, the infantile thyroid is eminently dependent on an adequate and steady iodine supply. In the first month of life, when milk is the only energy- and nutrient provider, infants fed a commercial formula regularly have a sufficient iodine supply. However, breastfed infants, who depend on maternal iodine status, frequently show an inadequate iodine intake. Furthermore, iodine intake is critical when complementary food (CF) is introduced. Especially homemade CF is poor in iodine, but also commercial CFs are only partly fortified. A simultaneous inadequate iodine supply of the breastfeeding mother and the preferential use of mostly iodine-poor organic milk cannot ensure an adequate iodine supply of the infant. In terms of an improvement of nutrient supply, especially concerning an unhindered brain development, the corresponding German reference value for iodine intake of infants until age 4 month should be raised from currently 40 microg/d to at least 60 microg/d (WHO-reference: 90 microg/d). PMID:20665419

  15. Effects of the air pressure on the wave-packet dynamics of gaseous iodine molecules at room temperature

    NASA Astrophysics Data System (ADS)

    Fan, Rongwei; He, Ping; Chen, Deying; Xia, Yuanqin; Yu, Xin; Wang, Jialing; Jiang, Yugang

    2013-02-01

    Based on ultrafast laser pulses, time-resolved resonance enhancement coherent anti-Stokes Raman scattering (RE-CARS) is applied to investigate wave-packet dynamics in gaseous iodine. The effects of air pressure on the wave-packet dynamics of iodine molecules are studied at pressures ranging from 1.5 Torr to 750 Torr. The RE-CARS signals are recorded in a gas cell filled with a mixture of about 0.3 Torr iodine in air buffer gas at room temperature. The revivals and fractional revival structures in the wave-packet signal are found to gradually disappear with rising air pressure up to 750 Torr, and the decay behaviors of the excited B-state and ground X-state become faster with increasing air pressure, which is due to the collision effects of the molecules and the growing complexity of the spectra at high pressures.

  16. Dynamics of production of iodine atoms by dissociation of iodides in a pulsed self-sustained discharge

    SciTech Connect

    Vagin, Nikolai P; Kochetov, Igor' V; Napartovich, A P; Yuryshev, Nikolai N

    2013-07-31

    Absorption at the laser transition has been used for the first time to assess the evolution of concentration of iodine atoms in a pulsed self-sustained discharge in mixtures of iodides with a buffer gas such as molecular nitrogen and helium. Dynamics of the iodine atom production is studied by the method of absorption spectroscopy. The dissociation of C{sub n}F{sub 2n+1}I and CnH{sub 2n+1}I (n = 1, 2) iodides is investigated. The energy required to produce atomic iodine is evaluated. The experimental data obtained for CF{sub 3}I are compared with the results of numerical simulations, their reasonable agreement being demonstrated. (active media)

  17. Recent data on iodine intake in Germany and Europe.

    PubMed

    Gärtner, Roland

    2016-09-01

    Iodine is essential for the synthesis of thyroid hormones. These regulate metabolism, promote growth, development and maturation of all organs, especially the brain. Most iodine is found in oceans and most continental soil and ground water is deficient in iodine. Therefore, around 2 billion individuals are estimated to have insufficient iodine intake and are at risk of iodine deficiency disorders. The best carrier for save iodine supplementation is salt, as the daily intake of salt is mainly constant. Due to the collaboration between international and national organisations and the salt industry, many developing and developed countries introduced universal salt iodization (USI) or have mandatory or voluntary fortification programs. In Germany as in most European countries the use of iodized salt is voluntary not only in household but also in the food industry. Two recent epidemiological surveys in Germany revealed that 33% of children and 32% of adults are still suffering from mild to moderate iodine deficiency. The best surrogate parameter for iodine deficiency is goitre. The goitre prevalence is around 30% in children as well as in adults which is in accordance with the documented iodine deficiency. From other European countries epidemiological derived data on iodine intake are only available from Denmark and Poland. Further efforts are under way to reveal the iodine status with proper methods in all European countries. On this background it might be possible to establish adequate iodine fortification programs in all European countries. PMID:27421794

  18. Iodine Deficiency in School Children in Aligarh District, India.

    PubMed

    Aslami, Ahmad Nadeem; Ansari, Mohammed A; Khalique, N; Kapil, Umesh

    2016-08-01

    We carried out this study to assess iodine deficiency disorders among school children of 6-12 years age group in Aligarh district of India. The prevalence of goiter was 5.2%. Median Urinary Iodine Excretion level was 150 ug/L; 22.5% of students had biochemical iodine deficiency. 50.4% households were consuming adequately iodized salt. PMID:27567653

  19. A quantitative model of the biogeochemical transport of iodine

    NASA Astrophysics Data System (ADS)

    Weng, H.; Ji, Z.; Weng, J.

    2010-12-01

    Iodine deficiency disorders (IDD) are among the world’s most prevalent public health problems yet preventable by dietary iodine supplements. To better understand the biogeochemical behavior of iodine and to explore safer and more efficient ways of iodine supplementation as alternatives to iodized salt, we studied the behavior of iodine as it is absorbed, accumulated and released by plants. Using Chinese cabbage as a model system and the 125I tracing technique, we established that plants uptake exogenous iodine from soil, most of which are transported to the stem and leaf tissue. The level of absorption of iodine by plants is dependent on the iodine concentration in soil, as well as the soil types that have different iodine-adsorption capacity. The leaching experiment showed that the remainder soil content of iodine after leaching is determined by the iodine-adsorption ability of the soil and the pH of the leaching solution, but not the volume of leaching solution. Iodine in soil and plants can also be released to the air via vaporization in a concentration-dependent manner. This study provides a scientific basis for developing new methods to prevent IDD through iodized vegetable production.

  20. Regenerable Iodine Water-Disinfection System

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

    1994-01-01

    Iodinated resin bed for disinfecting water regenerated to extend its useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle was manually controlled in demonstration, readily automated to start and stop according to signals and stop according to signals from concentration sensors. Further benefit of regeneration is that regeneration bed provides highly concentrated biocide source (200 mg/L) when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

  1. [Overall child development: beyond pharmacological iodine supplementation].

    PubMed

    Gavilán, Enrique; Jiménez de Gracia, Laura

    2013-12-01

    Iodine deficiency is a factor that may compromise child development, but is not the only one. Other health determinants, some of them outside the healthcare system, are able to influence development. Fighting iodine deficiency may be a pragmatic and useful strategy if it is found to be not maleficent, beneficial to health, and cost-effective, and does not make us lose the notion that child development goes beyond psychomotor or cognitive performance. This article analyzes such constraints from a critical point of view. PMID:23916171

  2. Mysterious iodine-overabundance in Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Dreibus, G.; Waenke, H.; Schultz, L.

    1986-01-01

    Halogen as well as other trace element concentrations in meteorite finds can be influenced by alteration processes on the Earth's surface. The discovery of Antarctic meteorites offered the opportunity to study meteorites which were kept in one of the most sterile environment of the Earth. Halogen determination in Antartic meteorites was compared with non-Antarctic meteorites. No correlation was found between iodine concentration and the weathering index, or terrestrial age. The halogen measurements indicate a contaminating phase rich in iodine and also containing chlorine. Possible sources for this contamination are discussed.

  3. A novel concept to derive iodine status of human populations from frequency distribution properties of a hair iodine concentration.

    PubMed

    Prejac, J; Višnjević, V; Drmić, S; Skalny, A A; Mimica, N; Momčilović, B

    2014-04-01

    Today, human iodine deficiency is next to iron the most common nutritional deficiency in developed European and underdeveloped third world countries, respectively. A current biological indicator of iodine status is urinary iodine that reflects the very recent iodine exposure, whereas some long term indicator of iodine status remains to be identified. We analyzed hair iodine in a prospective, observational, cross-sectional, and exploratory study involving 870 apparently healthy Croatians (270 men and 600 women). Hair iodine was analyzed with the inductively coupled plasma mass spectrometry (ICP MS). Population (n870) hair iodine (IH) respective median was 0.499μgg(-1) (0.482 and 0.508μgg(-1)) for men and women, respectively, suggesting no sex related difference. We studied the hair iodine uptake by the logistic sigmoid saturation curve of the median derivatives to assess iodine deficiency, adequacy and excess. We estimated the overt iodine deficiency to occur when hair iodine concentration is below 0.15μgg(-1). Then there was a saturation range interval of about 0.15-2.0μgg(-1) (r(2)=0.994). Eventually, the sigmoid curve became saturated at about 2.0μgg(-1) and upward, suggesting excessive iodine exposure. Hair appears to be a valuable and robust long term biological indicator tissue for assessing the iodine body status. We propose adequate iodine status to correspond with the hair iodine (IH) uptake saturation of 0.565-0.739μgg(-1) (55-65%). PMID:24629671

  4. Tomato fruits: a good target for iodine biofortification

    PubMed Central

    Kiferle, Claudia; Gonzali, Silvia; Holwerda, Harmen T.; Ibaceta, Rodrigo Real; Perata, Pierdomenico

    2013-01-01

    Iodine is a trace element that is fundamental for human health: its deficiency affects about two billion people worldwide. Fruits and vegetables are usually poor sources of iodine; however, plants can accumulate iodine if it is either present or exogenously administered to the soil. The biofortification of crops with iodine has therefore been proposed as a strategy for improving human nutrition. A greenhouse pot experiment was carried out to evaluate the possibility of biofortifying tomato fruits with iodine. Increasing concentrations of iodine supplied as KI or KIO3 were administered to plants as root treatments and the iodine accumulation in fruits was measured. The influences of the soil organic matter content or the nitrate level in the nutritive solution were analyzed. Finally, yield and qualitative properties of the biofortified tomatoes were considered, as well as the possible influence of fruit storage and processing on the iodine content. Results showed that the use of both the iodized salts induced a significant increase in the fruit’s iodine content in doses that did not affect plant growth and development. The final levels ranged from a few mg up to 10 mg iodine kg - 1 fruit fresh weight and are more than adequate for a biofortification program, since 150 μg iodine per day is the recommended dietary allowance for adults. In general, the iodine treatments scarcely affected fruit appearance and quality, even with the highest concentrations applied. In contrast, the use of KI in plants fertilized with low doses of nitrate induced moderate phytotoxicity symptoms. Organic matter-rich soils improved the plant’s health and production, with only mild reductions in iodine stored in the fruits. Finally, a short period of storage at room temperature or a 30-min boiling treatment did not reduce the iodine content in the fruits, if the peel was maintained. All these results suggest that tomato is a particularly suitable crop for iodine biofortification programs

  5. Advances in chemical lasers

    SciTech Connect

    Miller, D.J.

    1987-09-25

    High-power chemical lasers thrive in an array of special environments and present many fascinating associated subjects ripe for developmental research. Included are processes to produce the source reactants; supersonic mixing and reacting flow fields; the production and dissipation of multiple vibrational-rotational molecular states; optical gain extraction in complex geometries; media inhomogeneity effects, and waste energy and reaction products removal. Some configurations require wavelength selectivity, special optical components, and coherent cavity or beam combining. In recent years, progress has been made in these areas on behalf of continuous-wave and repetitively pulsed hydrogen fluoride and deuterium fluoride lasers, subsonic and supersonic oxygen-iodine lasers, and potential shorter wavelength chemical lasers based on chemically excited higher electronic states. This paper presents a brief review of the technical approach of some of the technology areas, and the status in achieving practical, integrated high-power chemical lasers.

  6. Source And Sink Of Iodine For Drinking Water

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Flanagan, David T.; Gibbons, Randall E.

    1991-01-01

    Proposed system for controlling concentration of iodine in potable water exploits temperature dependence of equilibrium partition of iodine between solution in water and residence in ion-exchange resin. Used to maintain concentration of iodine sufficient to kill harmful microbes, but not so great to make water unpalatable. Requires little attention, yet controls concentration of iodine more precisely than iodination and deiodination by manual techniques. Conceived for use aboard spacecraft, system has terrestrial applications in regions where water must be kept potable, resupply difficult, and system must operate largely unattended.

  7. Optical and physical effects of iodine in chalcohalide glasses

    NASA Astrophysics Data System (ADS)

    MacKinnon, Robin J.; Heo, Jong; Sigel, George H., Jr.

    1990-05-01

    Tellurium and iodine were added to a base chalcogenide glass composition (Ge33Asl2Se5S) to compare their effects on physical and optical properties. Iodine decreased the glass transition temperature and increased thermal expansion to a greater extent than tellurium. However, density was lowered by the presence of iodine and increased by tellurium. Examination of the multiphonon absorption edge in the 300-900 cm1 range revealed that iodine and tellurium occupy different structural sites which accounts for their varied effect on physical properties. There appears to be no advantage of iodine versus tellurium additions with regard to optical fiber applications based on the results obtained.

  8. Dry method for recycling iodine-loaded silver zeolite

    DOEpatents

    Thomas, Thomas R.; Staples, Bruce A.; Murphy, Llewellyn P.

    1978-05-09

    Fission product iodine is removed from a waste gas stream and stored by passing the gas stream through a bed of silver-exchanged zeolite until the zeolite is loaded with iodine, passing dry hydrogen gas through the bed to remove the iodine and regenerate the bed, and passing the hydrogen stream containing the hydrogen iodide thus formed through a lead-exchanged zeolite which adsorbs the radioactive iodine from the gas stream and permanently storing the lead-exchanged zeolite loaded with radioactive iodine.

  9. Iodine insufficiency: a global health problem?

    PubMed

    Swanson, Christine A; Pearce, Elizabeth N

    2013-01-01

    As a result of collaborative efforts with international organizations and the salt industry, many developing and developed countries practice universal salt iodization (USI) or have mandatory salt fortification programs. As a consequence, the prevalence of iodine deficiency decreased dramatically. The United States and Canada are among the few developed countries that do not practice USI. Such an undertaking would require evidence of deficiency among vulnerable population groups, including pregnant women, newborns, and developing infants. Government agencies in the United States rely heavily on data from NHANES to assess the iodine status of the general population and pregnant women in particular. NHANES data suggest that pregnant women in the United States remain mildly deficient. This is important, because the developing fetus is dependent on maternal iodine intake for normal brain development throughout pregnancy. Professional societies have recommended that pregnant and lactating women, or those considering pregnancy, consume a supplement providing 150 μg iodine daily. The United States and Canada collaborate on the daily recommended intake and are also confronted with the challenge of identifying the studies needed to determine if USI is likely to be beneficial to vulnerable population groups without exposing them to harm. PMID:24038248

  10. Iodine as propellant for electric space propulsion

    NASA Astrophysics Data System (ADS)

    Grondein, Pascaline; Chabert, Pascal; Aanesland, Ane

    2014-10-01

    In PEGASES (an electric gridded thruster) both positive and negative ions are expelled after extraction from an ion-ion plasma formed downstream a localized magnetic field placed a few centimeters from the ionization region. For this thruster concept, we believe that Iodine is the best candidate. Its advantages are multiple: heavy and therefore good for high thrust, low ionization threshold and high electronegativity (the latter crucial for PEGASES) leading to high ion-ion densities and low RF power, at solid state at STP with a high vapor, and finally inexpensive. Iodine is also di-atomic and therefore energy loss in dissociation processes are reduced compared to SF6. We present here a dedicated experimental set-up intended for iodine experiments. The injection system consists of an evaporation chamber with temperature controlled gas lines and vacuum chamber to control condensation. A global model of the iodine electronegative plasma will be developed to compare and predict the plasma behavior and composition inside the thruster. The main challenge in this model is to reproduce the conditions of a strongly segregated plasma with two regions: one with rather high electron temperature and low electronegativity and the other an ion-ion plasma with low temperature.

  11. Iodine retention during evaporative volume reduction

    DOEpatents

    Godbee, H.W.; Cathers, G.I.; Blanco, R.E.

    1975-11-18

    An improved method for retaining radioactive iodine in aqueous waste solutions during volume reduction is disclosed. The method applies to evaporative volume reduction processes whereby the decontaminated (evaporated) water can be returned safely to the environment. The method generally comprises isotopically diluting the waste solution with a nonradioactive iodide and maintaining the solution at a high pH during evaporation.

  12. METHOD OF REMOVING RADIOACTIVE IODINE FROM GASES

    DOEpatents

    Silverman, L.

    1962-01-23

    A method of removing radioactive iodine from a gaseous medium is given in which the gaseous medium is adjusted to a temperature not exceeding 400 deg C and then passed over a copper fibrous pad having a coating of cupric sulfide deposited thereon. An ionic exchange on the pad results in the formation of cupric iodide and the release of sulfur. (AEC)

  13. Volcanic iodine monoxide observed from satellite

    NASA Astrophysics Data System (ADS)

    Schönhardt, Anja; Richter, Andreas; Theys, Nicolas; Burrows, John P.

    2016-04-01

    Halogen species are injected into the atmosphere by volcanic eruptions. Previous studies have reported observations of chlorine and bromine oxides in volcanic plumes. These emissions have a significant impact on the chemistry within the plume as well as on upper troposphere and lower stratosphere composition, e.g. through ozone depletion. Volcanic halogen oxides have been observed from different platforms, from ground, aircraft and from satellite. The present study reports on satellite observations of iodine monoxide, IO, following the eruption of the Kasatochi volcano, Alaska, in August 2008. Satellite measurements from the SCIAMACHY sensor onboard ENVISAT are used. In addition, the volcanic IO plume is also retrieved from GOME-2 / MetOP-A measurements. Largest IO column amounts reach up to more than 4×1013 molec/cm2, the results from both instruments being consistent. The IO plume has a very similar shape as the BrO plume and is observed for several days following the eruption. The present observations are the first evidence that besides chlorine and bromine oxides also iodine oxides can be emitted by volcanic eruptions. This has important implications for atmospheric composition and background iodine levels. Together with the simultaneous observations of BrO and SO2, iodine monoxide columns can possibly provide insights into the composition of the magma.

  14. Halogen Bonding in Hypervalent Iodine Compounds.

    PubMed

    Catalano, Luca; Cavallo, Gabriella; Metrangolo, Pierangelo; Resnati, Giuseppe; Terraneo, Giancarlo

    2016-01-01

    Halogen bonds occur when electrophilic halogens (Lewis acids) attractively interact with donors of electron density (Lewis bases). This term is commonly used for interactions undertaken by monovalent halogen derivatives. The aim of this chapter is to show that the geometric features of the bonding pattern around iodine in its hypervalent derivatives justify the understanding of some of the longer bonds as halogen bonds. We suggest that interactions directionality in ionic and neutral λ(3)-iodane derivatives is evidence that the electron density distribution around iodine atoms is anisotropic, a region of most positive electrostatic potential exists on the extensions of the covalent bonds formed by iodine, and these positive caps affect, or even determine, the crystal packing of these derivatives. For instance, the short cation-anion contacts in ionic λ(3)-iodane and λ(5)-iodane derivatives fully match the halogen bond definition and geometrical prerequisites. The same holds for the short contacts the cation of ionic λ(3)-iodanes forms with lone-pair donors or the short contacts given by neutral λ(3)-iodanes with incoming nucleophiles. The longer and weaker bonds formed by iodine in hypervalent compounds are usually called secondary bondings and we propose that the term halogen bond can also be used. Compared to the term secondary bond, halogen bond may possibly be more descriptive of some bonding features, e.g., its directionality and the relationships between structure of interacting groups and interaction strength. PMID:26809623

  15. Arthur von Hubl and the Iodine Value

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The iodine value is still one of the most commonly applied indices in fatty acid chemistry. Its introduction was a milestone in analyzing fats and oils as well as describing their structure-property relationships, although it can be considered largely outdated because modern analytical methods such...

  16. Factors Influencing the Occurrence of High Numbers of Iodine-Resistant Bacteria in Iodinated Swimming Pools

    PubMed Central

    Favero, Martin S.; Drake, Charles H.

    1966-01-01

    It has been shown that, although iodinated swimming-pool waters are usually free from coliform bacteria and enterococci, the total counts frequently become relatively high. Pseudomonas alcaligenes and Alcaligenes faecalis have been shown to account for most of these high counts. It was of interest, therefore, to compare the microbial flora of four alternately chlorinated and iodinated swimming pools. By means of the membrane filter method and suitable selective media, examinations were made for total viable counts, coliform bacteria, enterococci, staphylococci, Streptococcus salivarius, and P. aeruginosa. Colonies also were picked from membrane filters incubated on standard plate count agar and identified. The results showed that, although viable counts were significantly higher during the iodinated periods, the specific types of bacteria determined were either fewer than or the same as in chlorinated periods. During chlorination, the predominant microbial flora consisted of staphylococci and members of the genus Bacillus. During iodination, however, the P. alcaligenes-A. faecalis group accounted for 92 to 99% of the microbial flora. The accumulation of high numbers of these bacteria was shown to be due to their iodine resistance and their ability to grow rapidly in pool water in the absence of free iodine. PMID:5927040

  17. [Antihyperlipidemic effect of iodine egg: search for active ingredients and their iodine contents].

    PubMed

    Kaji, K; Seyama, Y; Yamashita, S

    1984-04-01

    Active fractions that possess the hypocholesterolemic effect of iodine egg yolk lipid fraction have been investigated with male Wistar strain rats fed on a cholesterol-rich diet. Iodine egg yolk lipid was extracted by Folch's (chloroform: methanol) method and was refractionated into a neutral lipid (IEY-NL) fraction and a polar lipid (IEY-PL) fraction. The iodine content in each fraction was determined. The animals were kept on the cholesterol-rich diet for 5 days, and then they were fed the fractions in addition to the above diet for 10 more days. The hypocholesterolemic effect was seen most significantly with the IEY-NL fraction. The serum total cholesterol level in rats receiving this fraction was 70% as compared with that of the Ch group (fed on the cholesterol diet). However, the liver total cholesterol level was not affected or rather increased by the IEY-NL fraction. Another fraction (IEY-PL) showed no such effect. Iodine content in the IEY-NL fraction was quite low (0.2 ppm) compared with the other fractions. The daily dose in terms of iodine in the IEY-NL fraction was only the amount equivalent to 1/50 of the reported daily requirement for the rat. The IEY-NL fraction induced the hypocholesterolemic effect, though it contained only a trace of iodine. PMID:6540225

  18. Radioactive iodine separations and waste forms development.

    SciTech Connect

    Krumhansl, James Lee; Nenoff, Tina Maria; Garino, Terry J.; Rademacher, David

    2010-04-01

    Reprocessing nuclear fuel releases gaseous radio-iodine containing compounds which must be captured and stored for prolonged periods. Ag-loaded mordenites are the leading candidate for scavenging both organic and inorganic radioiodine containing compounds directly from reprocessing off gases. Alternately, the principal off-gas contaminant, I2, and I-containing acids HI, HIO3, etc. may be scavenged using caustic soda solutions, which are then treated with bismuth to put the iodine into an insoluble form. Our program is focused on using state-of-the-art materials science technologies to develop materials with high loadings of iodine, plus high long-term mechanical and thermal stability. In particular, we present results from research into two materials areas: (1) zeolite-based separations and glass encapsulation, and (2) in-situ precipitation of Bi-I-O waste forms. Ag-loaded mordenite is either commercially available or can be prepared via a simple Ag+ ion exchange process. Research using an Ag+-loaded Mordenite zeolite (MOR, LZM-5 supplied by UOP Corp.) has revealed that I2 is scavenged in one of three forms, as micron-sized AgI particles, as molecular (AgI)x clusters in the zeolite pores and as elemental I2 vapor. It was found that only a portion of the sorbed iodine is retained after heating at 95o C for three months. Furthermore, we show that even when the Ag-MOR is saturated with I2 vapor only roughly half of the silver reacted to form stable AgI compounds. However, the Iodine can be further retained if the AgI-MOR is then encapsulated into a low temperature glass binder. Follow-on studies are now focused on the sorption and waste form development of Iodine from more complex streams including organo-iodine compounds (CH3I). Bismuth-Iodate layered phases have been prepared from caustic waste stream simulant solutions. They serve as a low cost alternative to ceramics waste forms. Novel compounds have been synthesized and solubility studies have been completed

  19. A review on the metabolic disorders of iodine deficiency.

    PubMed

    Mansourian, Azad Reza

    2011-04-01

    Iodine is in the crucial parts of two hormones of T4 and T3 produced by the thyroid glands which are essential for all the aspects of human metabolisms. It is demonstrated that iodine deficiency can be considered as sole cause of many thyroid abnormalities including mental disorders. Iodine deficiency of sufficient degree to cause hypothyroidism during fetus life and early infancy will be accompanied with brain abnormality possibly to the stage of mental retardation. The iodine deficiency among subjects in their early stage of childhood is not as severe as those in their fetus or infancy. In adult subjects the sever iodine deficiency can be also associated with mental disorders due to the direct side effects of hypothyroidism occurred by lack of iodine. The clinical manifestation of iodine deficiency show itself with psychological disorders in adult subjects. The status of iodine within blood can be evaluated through measurement of urinary iodine level and the low urinary concentration is an indicative of hypothyroidism. Mental retardation and brain damage due to iodine deficiency can be prevented if iodine supplementation prescribed duly on time. PMID:21902053

  20. A Review: Radiographic Iodinated Contrast Media-Induced Thyroid Dysfunction

    PubMed Central

    Leung, Angela M.; Braverman, Lewis E.; Brent, Gregory A.; Pearce, Elizabeth N.

    2015-01-01

    Context: Thyroid hormone production is dependent on adequate iodine intake. Excess iodine is generally well-tolerated, but thyroid dysfunction can occur in susceptible individuals after excess iodine exposure. Radiological iodinated contrast media represent an increasingly common source of excess iodine. Objective: This review will discuss the thyroidal response after acute exposure to excess iodine; contrast iodine-induced thyroid dysfunction; risks of iodine-induced thyroid dysfunction in vulnerable populations, such as the fetus, neonate, and patients with impaired renal function; and recommendations for the assessment and treatment of contrast iodine-induced thyroid dysfunction. Methods: Data for this review were identified by searching PubMed, Google Scholar, and references from relevant articles from 1948 to 2014. Conclusions: With the increase in the use of computed tomography scans in the United States, there is increasing risk of contrast-induced thyroid dysfunction. Patients at risk of developing iodine-induced thyroid dysfunction should be closely monitored after receiving iodinated contrast media and should be treated as needed. PMID:25375985

  1. The Importance of Adequate Iodine during Pregnancy and Infancy.

    PubMed

    Zimmermann, Michael B

    2016-01-01

    Iodine requirements are increased ≥50% during pregnancy. Iodine deficiency during pregnancy can cause maternal and fetal hypothyroidism and impair neurological development of the fetus. The consequences depend upon the timing and severity of the hypothyroidism; the most severe manifestation is cretinism. In iodine-deficient areas, controlled studies have demonstrated that iodine supplementation before or during early pregnancy eliminates new cases of cretinism, increases birth weight, reduces rates of perinatal and infant mortality and generally increases developmental scores in young children by 10-20%. Mild-to-moderate maternal iodine deficiency can cause thyroid dysfunction, but whether it impairs cognitive and/or neurological function in the offspring remains uncertain. In nearly all regions affected by iodine deficiency, salt iodization is the most cost-effective way of delivering iodine and improving maternal and infant health. PMID:27198746

  2. Metabolic engineering of the iodine content in Arabidopsis

    PubMed Central

    Landini, Martina; Gonzali, Silvia; Kiferle, Claudia; Tonacchera, Massimo; Agretti, Patrizia; Dimida, Antonio; Vitti, Paolo; Alpi, Amedeo; Pinchera, Aldo; Perata, Pierdomenico

    2012-01-01

    Plants are a poor source of iodine, an essential micronutrient for human health. Several attempts of iodine biofortification of crops have been carried out, but the scarce knowledge on the physiology of iodine in plants makes results often contradictory and not generalizable. In this work, we used a molecular approach to investigate how the ability of a plant to accumulate iodine can be influenced by different mechanisms. In particular, we demonstrated that the iodine content in Arabidopsis thaliana can be increased either by facilitating its uptake with the overexpression of the human sodium-iodide symporter (NIS) or through the reduction of its volatilization by knocking-out HOL-1, a halide methyltransferase. Our experiments show that the iodine content in plants results from a balance between intake and retention. A correct manipulation of this mechanism could improve iodine biofortification of crops and prevent the release of the ozone layer-threatening methyl iodide into the atmosphere. PMID:22468225

  3. The challenges of iodine supplementation: a public health programme perspective.

    PubMed

    Untoro, Juliawati; Timmer, Arnold; Schultink, Werner

    2010-02-01

    An adequate iodine intake during pregnancy, lactation and early childhood is particularly critical for optimal brain development of the foetus and of children 7-24 months of age. While the primary strategy for sustainable elimination of iodine deficiency remains universal salt iodisation, the World Health Organization and the United Nations Children's Fund recommend a complementary strategy of iodine supplements as a temporary measure when salt iodisation could not be implemented. This article aims to review current evidence on efficacy and implications of implementing iodine supplementation as a public health measure to address iodine deficiency. Iodine supplementation seems unlikely to reach high coverage in a rapid, equitable and sustained way. Implementing the programme requires political commitment, effective and efficient supply, distribution and targeting, continuous education and communication and a robust monitoring system. Thus, universal salt iodisation should remain the primary strategy to eliminate iodine deficiency. PMID:20172473

  4. Research Spotlight: Ozone-destroying iodine measured in Arctic atmosphere

    NASA Astrophysics Data System (ADS)

    Tretkoff, Ernie

    2011-01-01

    Iodine in the atmosphere can destroy ozone and can also accelerate bromine-catalyzed ozone depletion. Iodine has been measured in the Antarctic atmosphere at levels that cause significant ozone depletion. Mahajan et al. now report detailed measurements of iodine in the Arctic lower troposphere above Hudson Bay. They observed episodes of elevated levels of iodine monoxide as well as other iodine compounds. They suggest that the iodine monoxide probably originated from organoiodine compounds released from ice and seawater algae in areas of open water surrounded by sea ice in Hudson Bay. The emissions of these iodinated compounds will probably grow if sea ice cover in the Arctic continues to decrease. (Journal of Geophysical Research-Atmospheres, doi:10.1029/2009JD013665, 2010)

  5. Iodine Revolatilization in a Grand Gulf Loca

    SciTech Connect

    Beahm, E.C.; Weber, C.F.

    1999-01-01

    The TRENDS models are applied at each time step to each control volume. Significant amounts of water occur only in the wetwell and drywell sump (the refueling pool is not a factor, as discussed earlier). In Fig. 2, we show the radiolytic acid production feeding into each of these pools. Since the water is initially neutral and no chemical additives are present, the acid additions are the major factors affecting pH. In Fig. 3, we see the downward trend of pH resulting from these acid additions. The conversion of iodide (I{sup {minus}}) to molecular iodine (I{sub 2}) is most noticeable in the wetwell, since this is the repository of most iodide and HCl. Gradually, during the transient small amounts of more volatile iodine are formed. While iodide remains the dominant form, noticeable amounts of I{sub 2} and intermediate species are created. Once produced in water, some I{sub 2} is free to evaporate into airspace. Fig. 4 indicates the increase in all airborne iodine throughout the transient. This is compared to the MELCOR result for CsI aerosol, which decreases dramatically due to containment sprays. The I{sub 2} in the airspace can be vented to the enclosure building or the environment. In the present accident sequence, the only path to the environment was through the SGTS, which was assumed to operate as in MELCOR. However, both are dwarfed by the MELCOR gaseous release during the first 12 h because MELCOR does not model spray washout of gaseous iodine. Steadily increasing throughout the transient, the revolatilization release is eventually more than an order-or-magnitude higher than the MELCOR aerosol release. Also, 99% of iodine flowing directly through the SGTS was retained in filters. The remaining 1% was released to the environment. In addition, a small flow bypassing the SGTS filters vented directly into the environment. The total released from these two paths is shown in Fig. 5.

  6. Assessing iodine intake, iodine status, and the effects of maternal iodine supplementation: introduction to articles arising from 3 workshops held by the NIH Office of Dietary Supplements.

    PubMed

    Ershow, Abby G; Goodman, Gay; Coates, Paul M; Swanson, Christine A

    2016-09-01

    The NIH Office of Dietary Supplements (ODS) convened 3 workshops on iodine nutrition in 2014, each held in Rockville, Maryland. These workshops were part of the ongoing ODS Iodine Initiative, begun in 2011 in response to concerns that US pregnant women may be at risk of iodine deficiency and that a high fraction of prenatal dietary supplements do not contain the recommended amounts of iodine. The primary purpose of the workshops was to consider the data and resources necessary to evaluate the clinical and public health benefits and risks of maternal iodine supplementation in the United States. The first workshop focused on the assessment of iodine intake, the second focused on the assessment of iodine status, and the third focused on the design and interpretation of clinical trials of maternal iodine supplementation. Here we provide the background of the ODS Iodine Initiative, summarize the 3 workshops held in 2014, and introduce the articles that arose from the workshops and are published in this supplement issue. PMID:27534646

  7. Long-term migration of iodine in sedimentary rocks based on iodine speciation and 129I/127I ratio

    NASA Astrophysics Data System (ADS)

    Togo, Y.; Takahashi, Y.; Amano, Y.; Matsuzaki, H.; Suzuki, Y.; Muramatsu, Y.; Iwatsuki, T.

    2012-12-01

    [Introduction] 129I is one of the available indexes of long-term migration of groundwater solutes, because of its long half-life (15.7 million years) and low sorption characteristics. The Horonobe underground research center (Japan Atomic Energy Agency), at which are conducted research and development of fundamental techniques on geological disposal of high-level radioactive waste, is an appropriate site for natural analogue studies, because iodine concentration in groundwater is high in this area. To predict iodine behavior in natural systems, speciation of iodine is essential because of different mobility among each species. In this study, we determined iodine speciation and129I/127I isotope ratios of rock and groundwater samples to investigate long term migration of iodine. [Methods] All rock and groundwater samples were collected at Horonobe underground research center. The region is underlain mainly by Neogene to Quaternary marine sedimentary rocks, the Wakkanai Formation (Wk Fm, siliceous mudstones), and the overlying Koetoi Formation (Kt Fm, diatomaceous mudstones). Iodine species in rock samples were determined by iodine K-edge X-ray absorption near edge structure (SPring-8 BL01B1). Thin sections of rock samples were prepared, and iodine mapping were obtained by micro-XRF analysis (SPring-8 BL37XU). Iodine species (IO3-, I-, and organic I) in groundwater were separately detected by high performance liquid chromatography connected to ICP-MS. The 129I/127I ratios in groundwater and rock samples were measured by accelerator mass spectrometry (MALT, Univ. of Tokyo). Iodine in rock samples were separated by pyrohydrolysis and water extraction. [Results and discussion] Concentration of iodine in groundwater varied widely and was much higher than that of seawater showing a high correlation with that of chlorine (R2 = 0.90). Species of iodine in groundwater was mainly I-. Iodine in rock samples decreased near the boundary between Wk and Kt Fms. Iodine K-edge XANES

  8. [Hyperthyreosis and hypothyreosis after use of iodine-containing natural products and iodine-containing vitamin and mineral supplements].

    PubMed

    Jørgensen, H; Svindland, O

    1991-10-30

    Excess iodine is known to affect thyroid function, and in predisposed individuals even a moderately increased iodine intake may cause hypothyreosis or hyperthyreosis. In our material, one patient developed hypothyreosis and five patients hyperthyreosis after using commercial health products containing iodine. The daily intake of iodine was 100-300 micrograms for a period of four months to four years. Except for a positive antibody titer to microsomal thyroid-antigen no obvious predisposing conditions were present. The thyroid function normalized two to three months after withdrawal of the iodine product. The hyperthyroid patients accounted for about 5% of all cases of hyperthyrosis seen in our hospitals during the period in question (one and a half years). It is concluded that "health products", containing iodine should be subjected to public control and the iodine content regulated. This would mean changing the present practice of no such regulation. PMID:1948937

  9. Quantification of total iodine in intact granular starches of different botanical origin exposed to iodine vapor at various water activities.

    PubMed

    Manion, Bruce; Ye, Mei; Holbein, Bruce E; Seetharaman, Koushik

    2011-11-01

    Iodine has been used as an effective tool for studying both the structure and composition of dispersed starch and starch granules. In addition to being employed to assess relative amylose contents for starch samples, it has been used to look at the molecular mobility of the glucose polymers within intact starch granules based on exposure to iodine vapor equilibrated at different water activities. Starches of different botanical origin including corn, high amylose corn, waxy corn, potato, waxy potato, tapioca, wheat, rice, waxy rice, chick pea and mung bean were equilibrated to 0.33, 0.75, 0.97 water activities, exposed to iodine vapor and then absorbance spectra and LAB color were determined. In addition, a new iodine quantification method sensitive to <0.1% iodine (w/w) was employed to measure bound iodine within intact granular starch. Amylose content, particle size distribution of granules, and the density of the starch were also determined to explore whether high levels of long linear glucose chains and the surface area-to-volume ratio were important factors relating to the granular iodine binding. Results showed, in all cases, starches complexed more iodine as water content increased and waxy starches bound less iodine than their normal starch counterparts. However, much more bound iodine could be measured chemically with waxy starches than was expected based on colorimetric determination. Surface area appeared to be a factor as smaller rice and waxy rice starch granules complexed more iodine, while the larger potato and waxy potato granules complexed less than would be expected based on measured amylose contents. Corn, high amylose corn, and wheat, known to have starch granules with extensive surface pores, bound higher levels of iodine suggesting pores and channels may be an important factor giving iodine vapor greater access to bind within the granules. Exposing iodine vapor to moisture-equilibrated native starches is an effective tool to explore starch

  10. Development and validation of an iodine-specific FFQ to estimate iodine intake in Australian pregnant women.

    PubMed

    Condo, Dominique; Makrides, Maria; Skeaff, Sheila; Zhou, Shao J

    2015-03-28

    Adequate iodine is important during pregnancy to ensure optimal growth and development of the offspring. We validated an iodine-specific FFQ (I-FFQ) for use in Australian pregnant women. A forty-four-item I-FFQ was developed to assess iodine intake from food and was administered to 122 pregnant women at 28 weeks gestation. Iodine supplement use was captured separately at 28 weeks gestation. Correlation between iodine intake from food estimated using the I-FFQ and a 4 d weighed food record as well as correlation between total iodine intake and 24 h urinary iodine excretion (UIE), 24 h urinary iodine concentration (UIC), spot UIC and thyroid function were assessed at 28 weeks gestation. A moderate correlation between the two dietary methods was shown (r 0·349, P< 0·001), and it was strengthened with the addition of iodine supplements (r 0·876, P<0·001). There was a fair agreement (k= 0·28, P<0·001) between the two dietary measures in the classification of women as receiving adequate (≥160 μg/d) or inadequate (<160 μg/d) iodine intake from food, but the limits of agreement from the Bland-Altman plot were large. Total iodine intake was associated with 24 h UIE (β = 0·488, P<0·001) but not with spot UIC. Iodine intake from food using the I-FFQ was assessed at study entry (<20 weeks gestation) in addition to 28 weeks gestation, and there was a strong correlation in iodine intake at the two time points (r 0·622, P<0·001), which indicated good reproducibility. In conclusion, the I-FFQ provides a valid tool for estimating iodine intake in pregnant women and can be used to screen women who are at risk of inadequate intake. PMID:25744430

  11. Genetic alterations of differentiated thyroid carcinoma in iodine-rich and iodine-deficient countries.

    PubMed

    Vuong, Huy Gia; Kondo, Tetsuo; Oishi, Naoki; Nakazawa, Tadao; Mochizuki, Kunio; Inoue, Tomohiro; Tahara, Ippei; Kasai, Kazunari; Hirokawa, Mitsuyoshi; Tran, Thong Minh; Katoh, Ryohei

    2016-08-01

    BRAF V600E mutation, RET rearrangements, and RAS mutations are the common genetic alterations in differentiated thyroid carcinomas derived from follicular thyroid cells. However, the relationship between these alterations and iodine intake is still controversial. To clarify the influence of iodine intake on the occurrence of differentiated thyroid carcinomas, we performed molecular analyses for two differentiated carcinomas, papillary thyroid carcinomas (PTCs) and follicular thyroid carcinomas (FTCs), from an iodine-rich country (Japan) and an iodine-deficient country (Vietnam). We examined 120 PTCs (67 Japanese and 53 Vietnamese) and 74 FTCs (51 Japanese and 23 Vietnamese). We carried out allele-specific polymerase chain reaction (AS-PCR) for BRAF V600E, PCR and direct sequencing for RAS mutations (codon 12, 13, and 61 in NRAS, HRAS, and KRAS), and RT-PCR for RET/PTC1 and RET/PTC3. BRAF V600E was present in 55/67 (82.1%) Japanese PTCs and 44/53 (83%) Vietnamese PTCs. RET/PTC1 was identified in only one PTC from each country, and no samples had RET/PTC3. NRAS mutation was found in 17/51 (33.3%) Japanese FTCs and 4/23 (17.4%) Vietnamese FTCs. NRAS mutation was cited in codon 61 (20 cases) and codon 12 (one case). None of FTCs had KRAS or HRAS mutations. There were no significant differences in the prevalence of BRAF V600E, RET/PTC, or RAS mutations between the two countries. Our study showed no differences in genetic alterations of thyroid cancers from iodine-rich and iodine-deficient countries, possibly suggesting that iodine intake might not affect the genetic alterations of differentiated thyroid cancer. PMID:27264674

  12. Iodine Deficiency and the Brain: Effects and Mechanisms.

    PubMed

    Redman, Kahla; Ruffman, Ted; Fitzgerald, Penelope; Skeaff, Sheila

    2016-12-01

    Iodine is an essential micronutrient needed in human diets. As iodine is an integral component of thyroid hormone, it mediates the effects of thyroid hormone on brain development. Iodine deficiency is the most prevalent and preventable cause of mental impairment in the world. The exact mechanism through which iodine influences the brain is unclear, but is generally thought to begin with genetic expression. Many brain structures and systems appear to be affected with iodine deficiency, including areas such as the hippocampus, microstructures such as myelin, and neurotransmitters. The clearest evidence comes from the studies examining cognition in the cases of iodine deprivation or interventions involving iodine supplementation. Nevertheless, there are many inconsistencies and gaps in the literature of iodine deficiency, especially over the lifespan. This paper summarizes the literature on this topic, suggests a causal mechanism for iodine's effect on the brain, and indicates areas for the future research (e.g., using magnetic resonance imaging (MRI) and functional MRI to examine how iodine supplementation facilitates cognitive functioning). PMID:25880137

  13. Safety of iodine based water sterilization for travelers.

    PubMed

    Goodyer, L; Behrens, R H

    2000-01-01

    The recent report by Khan et al. of an unexpectedly high concentration of free iodine in water filters, which may have led to the high proportion of abnormal thyroid function tests in Peace Corps workers, is of concern for travel advisors when asked to recommend suitable means of water sterilization. Many travelers use iodine based filters and/or chemicals for purification of water when traveling in areas with contaminated water supplies and may therefore be at risk of excess iodine intake. Aside from iodine impregnated resin filtration systems, tetraglycine hydroperiodide tablets, tincture of iodine 2% and more commonly, chlorine-based proprietary products are widely used to sterilize water for drinking, and usually purchased by travelers without advice on how they should be used. A single tetraglycine hydroperiodide tablet in a liter of water releases 8 mg of iodine in comparison to the 10 mg/liter released from the iodinated resin pumps described by Khan et al. Although the instructions for using iodine tincture are imprecise, the normal recommendation is 5 drops per liter of water, increasing this to 12 drops where Giardia cysts may be present. The lower of the two doses would yield about 2 mg/liter of free iodine per liter depending on the pipette used, although, because of the potassium iodide present in the formulation, a total of 4 mg iodine would be available for absorption. PMID:10689241

  14. Iodine Nutritional Status of School Children in Nauru 2015.

    PubMed

    Huang, Chun-Jui; Tseng, Chi-Lung; Chen, Harn-Shen; Garabwan, Chanda; Korovo, Samuela; Tang, Kam-Tsun; Won, Justin Ging-Shing; Hsieh, Chang-Hsun; Wang, Fan-Fen

    2016-01-01

    Little is known about iodine nutritional status in island countries in the Pacific Ocean. The primary objective of this study was to report for the first time the iodine nutritional status of people in Nauru. In addition, sources of iodine nutrition (i.e., water and salt) were investigated. A school-based cross-sectional survey of children aged 6-12 years was conducted in three primary schools of Nauru. Urinary iodine concentration (UIC) was determined by spot urine samples. Available water and salt samples in Nauru were collected for the measurement of iodine content. A food frequency questionnaire was conducted. The median UIC was 142 μg/L, and 25.2% and 7.4% of the population had median UIC below 100 μg/L and 50 μg/L, respectively. Natural iodine-containing foods such as seaweeds and agar were rare. Iodine was undetectable in Nauruan tank water, filtered tap water, and raindrops. Of the analyzed salt products, five kinds were non-iodized, and three were iodized (iodine content: 15 ppm, 65 ppm, and 68 ppm, respectively). The results indicate that the iodine status in Nauruan school children is adequate. Iodized salt may serve as an important source of iodine nutrition in Nauru. PMID:27563920

  15. Salt intake and iodine status of women in Samoa.

    PubMed

    Land, Mary-Anne; Webster, Jacqui L; Ma, Gary; Li, Mu; Su'a, Sarah Asi Faletoese; Ieremia, Merina; Viali, Satu; Faeamani, Gavin; Bell, A Colin; Quested, Christine; Neal, Bruce C; Eastman, Creswell J

    2016-01-01

    The objective of this study was to determine iodine nutrition status and whether iodine status differs across salt intake levels among a sample of women aged 18-45 years living in Samoa. A cross-sectional survey was completed and 24-hr urine samples were collected and assessed for iodine (n=152) and salt excretion (n=119). The median urinary iodine concentration (UIC) among the women was 88 μg/L (Interquartile range (IQR)=54-121 μg/L). 62% of the women had a UIC <100 μg/L. The crude estimated mean 24-hr urinary salt excretion was 6.6 (standard deviation 3.2) g/day. More than two-thirds (66%) of the women exceeded the World Health Organization recommended maximum level of 5 g/day. No association was found between median UIC and salt excretion (81 μg/L iodine where urinary salt excretion >=5 g/day versus 76 μg/L where urinary salt excretion <5 g/day; p=0.4). Iodine nutrition appears to be insufficient in this population and may be indicative of iodine deficiency disorders in Samoan women. A collaborative approach in monitoring iodine status and salt intake will strengthen both programs and greatly inform the level of iodine fortification required to ensure optimal iodine intake as population salt reduction programs take effect. PMID:26965773

  16. Ultrastable laser array at 633 nm for real-time dimensional metrology

    NASA Astrophysics Data System (ADS)

    Lawall, John; Pedulla, J. Marc; Le Coq, Yann

    2001-07-01

    We describe a laser system for very-high-accuracy dimensional metrology. A sealed-cavity helium-neon laser is offset locked to an iodine-stabilized laser in order to realize a secondary standard with higher power and less phase noise. Synchronous averaging is employed to remove the effect of the frequency modulation present on the iodine-stabilized laser. Additional lasers are offset locked to the secondary standard for use in interferometry. All servo loops are implemented digitally. The offset-locked lasers have intrinsic linewidths of the order of 2.5 kHz and exhibit a rms deviation from the iodine-stabilized laser below 18 kHz. The amplitude noise is at the shot-noise limit for frequencies above 700 kHz. We describe and evaluate the system in detail, and include a discussion of the noise associated with various types of power supplies.

  17. Iodine status in the Nordic countries – past and present

    PubMed Central

    Nyström, Helena Filipsson; Brantsæter, Anne Lise; Erlund, Iris; Gunnarsdottir, Ingibjörg; Hulthén, Lena; Laurberg, Peter; Mattisson, Irene; Rasmussen, Lone Banke; Virtanen, Suvi; Meltzer, Helle Margrete

    2016-01-01

    Background Adequate iodine nutrition is dependent on ground water content, seafood, and, as many countries use iodized cow fodder, dairy products. In most countries, salt fortification programs are needed to assure adequate iodine intake. Objectives The objectives are threefold: 1) to describe the past and present iodine situation in the Nordic countries, 2) to identify important gaps of knowledge, and 3) to highlight differences among the Nordic countries’ iodine biomonitoring and fortification policies. Design Historical data are compared with the current situation. The Nordic countries’ strategies to achieve recommended intake and urine iodine levels and their respective success rates are evaluated. Results In the past, the iodine situation ranged from excellent in Iceland to widespread goiter and cretinism in large areas of Sweden. The situation was less severe in Norway and Finland. According to a 1960 World Health Organization (WHO) report, there were then no observations of iodine deficiency in Denmark. In Sweden and Finland, the fortification of table salt was introduced 50–75 years ago, and in Norway and Finland, the fortification of cow fodder starting in the 1950s helped improve the population's iodine status due to the high intake of milk. In Denmark, iodine has been added to household salt and salt in bread for the past 15 years. The Nordic countries differ with regard to regulations and degree of governmental involvement. There are indications that pregnant and lactating women, the two most vulnerable groups, are mildly deficient in iodine in several of the Nordic countries. Conclusion The Nordic countries employ different strategies to attain adequate iodine nutrition. The situation is not optimal and is in need of re-evaluation. Iodine researchers, Nordic national food administrations, and Nordic governmental institutions would benefit from collaboration to attain a broader approach and guarantee good iodine health for all. PMID:27283870

  18. Iodine-xenon studies and the relax mass spectrometer

    NASA Astrophysics Data System (ADS)

    Gilmour, J. D.; Ash, R. D.; Lyon, I. C.; Johnston, W. A.; Hutchison, R.; Bridges, J. C.; Turner, G.

    1994-07-01

    RELAX combines a resonance ionization ion source with a cryogenic sample concentrator to achieve ultrasensitivity. Gas is extracted from samples using either a continuous wave laser microprobe based on an argon-ion laser or a filament microfurnace. Recent refinements in the operating procedure have resulted in optimum sensitivities such that detection rates of 1 cps are achieved from fewer than 500 atoms. A Xe-128 spike reservoir has also been added and characterized, allowing accurate determinations of absolute amounts of gas. We have completed a preliminary study of the iodine-xenon system in samples from the Bjurbole and Parnallee meteorites. Bjurbole chondrules ranging in mass from 5.45 mg to 260 micrograms were analyzed by laser microprobe. The results from these samples are consistent with an effectively uniform formation age, suggesting that the use of Bjurbole chondrules for calibration of this chronometer can be extended to samples in this size range. Samples from two chondrules from the Parnallee meteorite have been analyzed to date. An alpha-cristobalite-bearing chondrule (designated CB1) was found to have a formation age 4.62 +/- 0.44 Ma after Bjurboele, while a porphyritic olivine macrochondrule appears to have been reset after the decay of I-129(t1/2 17 Ma). Consideration of these results alongside Ar-Ar data from the macrochondrule and whole rock samples suggests that Parnallee has a complex history: The macrochondrule underwent an early postcrystallization degassing event but appears to have been essentially unaffected by the later (1.9 Ga) partial resetting of the bulk meteorite.

  19. Formation of iodinated trihalomethanes during UV/chloramination with iodate as the iodine source.

    PubMed

    Zhang, Tian-Yang; Lin, Yi-Li; Wang, An-Qi; Tian, Fu-Xiang; Xu, Bin; Xia, Sheng-Ji; Gao, Nai-Yun

    2016-07-01

    Iodinated trihalomethanes (I-THMs) are a group of emerging disinfection by-products with high toxicity, and iodide (I(-)) as well as iodinated organic compounds are expected to be their iodine sources. Nevertheless, in this study, iodate (IO3(-)) was proven to be a new iodine source of I-THM formation during UV/chloramination. In the iodate-containing waters (without any other iodine sources), I-THM formation increased with the increase of UV dose, IO3(-) and NH2Cl concentrations. With the increase of Br(-)/IO3(-) molar ratio, I-THM formation (especially for the brominated species) increased. Besides, NOM species could affect I-THM formation from IO3(-) during UV/chloramination. Fulvic acid could promote IO3(-) phototransformation to I(-) but humic acid impeded the production of I(-) during UV irradiation. Under realistic drinking water treatment conditions (DOC = 5.0 mg-C/L, IO3(-) = 12.7 μg-I/L, UV dose = 50 mJ/cm(2), NH2Cl = 5 mg-Cl2/L), CHCl2I was detected as 0.17 μg/L using solid-phase microextraction method, and the production rate of I-THMs from IO3(-) was about 7% of that from I(-). PMID:27105034

  20. Iodine-125 radiation of posterior uveal melanoma

    SciTech Connect

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  1. Models of iodine behavior in reactor containments

    SciTech Connect

    Weber, C.F.; Beahm, E.C.; Kress, T.S.

    1992-10-01

    Models are developed for many phenomena of interest concerning iodine behavior in reactor containments during severe accidents. Processes include speciation in both gas and liquid phases, reactions with surfaces, airborne aerosols, and other materials, and gas-liquid interface behavior. Although some models are largely empirical formulations, every effort has been made to construct mechanistic and rigorous descriptions of relevant chemical processes. All are based on actual experimental data generated at the Oak Ridge National Laboratory (ORNL) or elsewhere, and, hence, considerable data evaluation and parameter estimation are contained in this study. No application or encoding is attempted, but each model is stated in terms of rate processes, with the intention of allowing mechanistic simulation. Taken together, this collection of models represents a best estimate iodine behavior and transport in reactor accidents.

  2. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats.

    PubMed

    Piątkowska, Ewa; Kopeć, Aneta; Bieżanowska-Kopeć, Renata; Pysz, Mirosław; Kapusta-Duch, Joanna; Koronowicz, Aneta Agnieszka; Smoleń, Sylwester; Skoczylas, Łukasz; Ledwożyw-Smoleń, Iwona; Rakoczy, Roksana; Maślak, Edyta

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats' hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations. PMID:27043135

  3. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats

    PubMed Central

    Piątkowska, Ewa; Kopeć, Aneta; Bieżanowska-Kopeć, Renata; Pysz, Mirosław; Kapusta-Duch, Joanna; Koronowicz, Aneta Agnieszka; Smoleń, Sylwester; Skoczylas, Łukasz; Ledwożyw-Smoleń, Iwona; Rakoczy, Roksana; Maślak, Edyta

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats’ hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations. PMID:27043135

  4. A rate equation approach to gain saturation effects in laser mode calculations

    NASA Technical Reports Server (NTRS)

    Roberts, Lila F.

    1990-01-01

    Space exploration and research require large amounts of power. Solar pumped laser systems have been shown to have the potential for meeting the performance requirements necessary for power transmission in space. The successful design of laser systems for these applications will depend, in part, on having a clear understanding of the development of the dynamical processes in the laser cavity and on the effects that changes in physical and design parameters have on laser performance. In particular, it is necessary to know the amplitude and phase distributions of the laser beam at the output aperture when steady state operation is achieved in order to determine the far-field power distribution. The output from the laser will depend on the active medium, the optical environment of the active material and on the gain distribution in the active region as laser action builds up and reaches steady state. An important component in the design process will be a realistic model of the active laser cavity. A computer model of the laser cavity, based on Huygens' principle was developed. The code calculates the amplitude and phase of an optical wave reflected back and forth between the mirrors of a laser cavity. The original code assumes a gain distribution which does not change with the buildup of oscillations in the cavity. A step in the direction of realism is the inclusion of a saturable gain medium in the cavity. The objective is to incorporate saturation effects into the existing computer model.

  5. Iodine deficiency disorders (IDD) control in India

    PubMed Central

    Pandav, Chandrakant S.; Yadav, Kapil; Srivastava, Rahul; Pandav, Rijuta; Karmarkar, M.G.

    2013-01-01

    Iodine deficiency disorders (IDD) constitute the single largest cause of preventable brain damage worldwide. Majority of consequences of IDD are invisible and irreversible but at the same time these are preventable. In India, the entire population is prone to IDD due to deficiency of iodine in the soil of the subcontinent and consequently the food derived from it. To combat the risk of IDD, salt is fortified with iodine. However, an estimated 350 million people do not consume adequately iodized salt and, therefore, are at risk for IDD. Of the 325 districts surveyed in India so far, 263 are IDD-endemic. The current household level iodized salt coverage in India is 91 per cent with 71 per cent households consuming adequately iodized salt. The IDD control goal in India was to reduce the prevalence of IDD below 10 per cent in the entire country by 2012. What is required is a “mission approach” with greater coordination amongst all stakeholders of IDD control efforts in India. Mainstreaming of IDD control in policy making, devising State specific action plans to control IDD, strict implementation of Food Safety and Standards (FSS) Act, 2006, addressing inequities in iodized salt coverage (rural-urban, socio-economic), providing iodized salt in Public Distribution System, strengthening monitoring and evaluation of IDD programme and ensuring sustainability of IDD control activities are essential to achieve sustainable elimination of IDD in India. PMID:24135192

  6. Iodine source apportionment in the Malawian diet

    NASA Astrophysics Data System (ADS)

    Watts, M. J.; Joy, E. J. M.; Young, S. D.; Broadley, M. R.; Chilimba, A. D. C.; Gibson, R. S.; Siyame, E. W. P.; Kalimbira, A. A.; Chilima, B.; Ander, E. L.

    2015-10-01

    The aim of this study was to characterise nutritional-I status in Malawi. Dietary-I intakes were assessed using new datasets of crop, fish, salt and water-I concentrations, while I status was assessed for 60 women living on each of calcareous and non-calcareous soils as defined by urinary iodine concentration (UIC). Iodine concentration in staple foods was low, with median concentrations of 0.01 mg kg-1 in maize grain, 0.008 mg kg-1 in roots and tubers, but 0.155 mg kg-1 in leafy vegetables. Freshwater fish is a good source of dietary-I with a median concentration of 0.51 mg kg-1. Mean Malawian dietary-Iodine intake from food, excluding salt, was just 7.8 μg d-1 compared to an adult requirement of 150 μg d-1. Despite low dietary-I intake from food, median UICs were 203 μg L-1 with only 12% defined as I deficient whilst 21% exhibited excessive I intake. Iodised salt is likely to be the main source of dietary I intake in Malawi; thus, I nutrition mainly depends on the usage and concentration of I in iodised salt. Drinking water could be a significant source of I in some areas, providing up to 108 μg d-1 based on consumption of 2 L d-1.

  7. Iodination of glyceraldehyde 3-phosphate dehydrogenase

    PubMed Central

    Thomas, Jean O.; Harris, J. Ieuan

    1970-01-01

    1. A high degree of homology in the positions of tyrosine residues in glyceraldehyde 3-phosphate dehydrogenase from lobster and pig muscle, and from yeast, prompted an examination of the reactivity of tyrosine residues in the enzyme. 2. Iodination of the enzyme from lobster muscle with low concentrations of potassium tri-[125I]-iodide led to the identification of tyrosine residues of differing reactivity. Tyrosine-46 appeared to be the most reactive in the native enzyme. 3. When the monocarboxymethylated enzyme was briefly treated with small amounts of iodine, iodination could be confined almost entirely to tyrosine-46 in the lobster enzyme; tyrosine-39 or tyrosine-42, or both, were also beginning to react. 4. These three tyrosine residues were also those that reacted most readily in the carboxymethylated pig and yeast enzymes. 5. The difficulties in attaining specific reaction of the native enzyme are considered. 6. The differences between our results and those of other workers are discussed. ImagesPLATE 1PLATE 2 PMID:5530750

  8. Iodine source apportionment in the Malawian diet.

    PubMed

    Watts, M J; Joy, E J M; Young, S D; Broadley, M R; Chilimba, A D C; Gibson, R S; Siyame, E W P; Kalimbira, A A; Chilima, B; Ander, E L

    2015-01-01

    The aim of this study was to characterise nutritional-I status in Malawi. Dietary-I intakes were assessed using new datasets of crop, fish, salt and water-I concentrations, while I status was assessed for 60 women living on each of calcareous and non-calcareous soils as defined by urinary iodine concentration (UIC). Iodine concentration in staple foods was low, with median concentrations of 0.01 mg kg(-1) in maize grain, 0.008 mg kg(-1) in roots and tubers, but 0.155 mg kg(-1) in leafy vegetables. Freshwater fish is a good source of dietary-I with a median concentration of 0.51 mg kg(-1). Mean Malawian dietary-Iodine intake from food, excluding salt, was just 7.8 μg d(-1) compared to an adult requirement of 150 μg d(-1). Despite low dietary-I intake from food, median UICs were 203 μg L(-1) with only 12% defined as I deficient whilst 21% exhibited excessive I intake. Iodised salt is likely to be the main source of dietary I intake in Malawi; thus, I nutrition mainly depends on the usage and concentration of I in iodised salt. Drinking water could be a significant source of I in some areas, providing up to 108 μg d(-1) based on consumption of 2 L d(-1). PMID:26503697

  9. Iodine source apportionment in the Malawian diet

    PubMed Central

    Watts, M. J.; Joy, E. J. M.; Young, S. D.; Broadley, M. R.; Chilimba, A. D. C.; Gibson, R. S.; Siyame, E. W. P.; Kalimbira, A. A.; Chilima, B.; Ander, E. L.

    2015-01-01

    The aim of this study was to characterise nutritional-I status in Malawi. Dietary-I intakes were assessed using new datasets of crop, fish, salt and water-I concentrations, while I status was assessed for 60 women living on each of calcareous and non-calcareous soils as defined by urinary iodine concentration (UIC). Iodine concentration in staple foods was low, with median concentrations of 0.01 mg kg−1 in maize grain, 0.008 mg kg−1 in roots and tubers, but 0.155 mg kg−1 in leafy vegetables. Freshwater fish is a good source of dietary-I with a median concentration of 0.51 mg kg−1. Mean Malawian dietary-Iodine intake from food, excluding salt, was just 7.8 μg d−1 compared to an adult requirement of 150 μg d−1. Despite low dietary-I intake from food, median UICs were 203 μg L−1 with only 12% defined as I deficient whilst 21% exhibited excessive I intake. Iodised salt is likely to be the main source of dietary I intake in Malawi; thus, I nutrition mainly depends on the usage and concentration of I in iodised salt. Drinking water could be a significant source of I in some areas, providing up to 108 μg d−1 based on consumption of 2 L d−1. PMID:26503697

  10. Radioactive iodine therapy in cats with hyperthyroidism

    SciTech Connect

    Turrel, J.M.; Feldman, E.C.; Hays, M.; Hornof, W.J.

    1984-03-01

    Eleven cats with hyperthyroidism were treated with radioactive iodine (/sup 131/I). Previous unsuccessful treatments for hyperthyroidism included hemithyroidectomy (2 cats) and an antithyroid drug (7 cats). Two cats had no prior treatment. Thyroid scans, using technetium 99m, showed enlargement and increased radionuclide accumulation in 1 thyroid lobe in 5 cats and in both lobes in 6 cats. Serum thyroxine concentrations were high and ranged from 4.7 to 18 micrograms/dl. Radioactive iodine tracer studies were used to determine peak radioactive iodine uptake (RAIU) and effective and biological half-lives. Activity of /sup 131/I administered was calculated from peak RAIU, effective half-life, and estimated thyroid gland weight. Activity of /sup 131/I administered ranged from 1.0 to 5.9 mCi. The treatment goal was to deliver 20,000 rad to hyperactive thyroid tissue. However, retrospective calculations based on peak RAIU and effective half-life obtained during the treatment period showed that radiation doses actually ranged from 7,100 to 64,900 rad. Complete ablation of the hyperfunctioning thyroid tissue and a return to euthyroidism were seen in 7 cats. Partial responses were seen in 2 cats, and 2 cats became hypothyroid. It was concluded that /sup 131/I ablation of thyroid tumors was a reasonable alternative in the treatment of hyperthyroidism in cats. The optimal method of dosimetry remains to be determined.

  11. Advances in Synthetic Applications of Hypervalent Iodine Compounds.

    PubMed

    Yoshimura, Akira; Zhdankin, Viktor V

    2016-03-01

    The preparation, structure, and chemistry of hypervalent iodine compounds are reviewed with emphasis on their synthetic application. Compounds of iodine possess reactivity similar to that of transition metals, but have the advantage of environmental sustainability and efficient utilization of natural resources. These compounds are widely used in organic synthesis as selective oxidants and environmentally friendly reagents. Synthetic uses of hypervalent iodine reagents in halogenation reactions, various oxidations, rearrangements, aminations, C-C bond-forming reactions, and transition metal-catalyzed reactions are summarized and discussed. Recent discovery of hypervalent catalytic systems and recyclable reagents, and the development of new enantioselective reactions using chiral hypervalent iodine compounds represent a particularly important achievement in the field of hypervalent iodine chemistry. One of the goals of this Review is to attract the attention of the scientific community as to the benefits of using hypervalent iodine compounds as an environmentally sustainable alternative to heavy metals. PMID:26861673

  12. An experimental research on the mixing process of supersonic oxygen-iodine parallel streams

    NASA Astrophysics Data System (ADS)

    Wang, Zengqiang; Sang, Fengting; Zhang, Yuelong; Hui, Xiaokang; Xu, Mingxiu; Zhang, Peng; Zhao, Weili; Fang, Benjie; Duo, Liping; Jin, Yuqi

    2014-12-01

    The O2(1Δ)/I2 mixing process is one of the most important steps in chemical oxygen-iodine laser (COIL). Based on the chemical fluorescence method (CFM), a diagnostic system was set up to image electronically excited fluorescent I2(B3П0) by means of a high speed camera. An optimized data analysis approach was proposed to analyze the mixing process of supersonic oxygen-iodine parallel streams, employing a set of qualitative and quantitative parameters and a proper percentage boundary threshold of the fluorescence zone. A slit nozzle bank with supersonic parallel streams and a trip tab set for enhancing the mixing process were designed and fabricated. With the diagnostic system and the data analysis approach, the performance of the trip tab set was examined and is demonstrated in this work. With the mixing enhancement, the fluorescence zone area was enlarged 3.75 times. We have studied the mixing process under different flow conditions and demonstrated the mixing properties with different iodine buffer gases, including N2, Ar, He and CO2. It was found that, among the four tested gases, Ar had the best penetration ability, whilst He showed the best free diffusion ability, and both of them could be well used as the buffer gas in our experiments. These experimental results can be useful for designing and optimizing COIL systems.

  13. Air Density Measurements in a Mach 10 Wake Using Iodine Cordes Bands

    NASA Technical Reports Server (NTRS)

    Balla, Robert J.; Everhart, Joel L.

    2012-01-01

    An exploratory study designed to examine the viability of making air density measurements in a Mach 10 flow using laser-induced fluorescence of the iodine Cordes bands is presented. Experiments are performed in the NASA Langley Research Center 31 in. Mach 10 air wind tunnel in the hypersonic near wake of a multipurpose crew vehicle model. To introduce iodine into the wake, a 0.5% iodine/nitrogen mixture is seeded using a pressure tap at the rear of the model. Air density was measured at 56 points along a 7 mm line and three stagnation pressures of 6.21, 8.62, and 10.0 MPa (900, 1250, and 1450 psi). Average results over time and space show rho(sub wake)/rho(sub freestream) of 0.145 plus or minus 0.010, independent of freestream air density. Average off-body results over time and space agree to better than 7.5% with computed densities from onbody pressure measurements. Densities measured during a single 60 s run at 10.0 MPa are time-dependent and steadily decrease by 15%. This decrease is attributed to model forebody heating by the flow.

  14. Investigation of the single ionization of molecular iodine using velocity map imaging

    NASA Astrophysics Data System (ADS)

    Smith, Dale; Tagliamonti, Vincent; Dragan, James; Gibson, George

    2016-05-01

    We study the strong-field single ionization of iodine using velocity map imaging and find several distinct dissociation pathways leading to I2 -->I+ + I . To identify the molecular orbital from which the electron is removed we measured the kinetic energy release of the dissociation pathways as a function of laser wavelength, intensity, and polarization. We find that the many of these channels are not consistent with ionization from the first three valence orbitals of I2. We would like to acknowledge support from the NSF under Grant No. PHY-1306845.

  15. Electrolytic trapping of iodine from process gas streams

    DOEpatents

    Horner, Donald E.; Mailen, James C.; Posey, Franz A.

    1977-01-25

    A method for removing molecular, inorganic, and organic forms of iodine from process gas streams comprises the electrolytic oxidation of iodine in the presence of cobalt-III ions. The gas stream is passed through the anode compartment of a partitioned electrolytic cell having a nitric acid anolyte containing a catalytic amount of cobalt to cause the oxidation of effluent iodine species to aqueous soluble species.

  16. [Iodine deficiency in pregnancy--a continuing public health problem].

    PubMed

    Szybiński, Zbigniew

    2005-01-01

    Iodine prophylaxis in Poland started in 1997 and is based on mandatory iodzation of household salt with 20-40 mg KI/ 1 kg, supplementation of bottle fed infants with iodized formulas with 10,0 microg KI/100 ml, and a voluntary supplementation of pregnant and breast feeding women with additional 100-150 microg of iodine/ day. Last evaluation of efficacy of the iodine prophylaxis performed in 2003 by WHO and International Council for the Control of Iodine Deficiency Disorders allocated Poland within the group of the European countries with sufficient iodine supplementation on the population level. However according to data of the Institute of Mather and Chield in Poland, around 50 % of pregnant women only is additionally supplemented with iodine. Iodine deficiency during pregnancy even as a moderate iodine deficiency, creates a risk of mental retardation, perinatal complication like low and very low births weigt of neonates with increased perinatal mortality rate and late consequences in adult life: metabolic syndrom and type 2 diabetes. Another limitation of the actual model of iodine prophylaxis in Poland, it is too high consumption of natrum chloride (over 5,0 g of household salt/day/ capita). It is around 50% over WHO recommendation. Intensive preventive program against hypertension, type 2 diabetes, atherosclerosis, osteoporosis and some neoplasmatic diseases includes limitation of natrum chloride consumption- as one of the risk factors. Therefore new scope of the National Programme for Elimination of Iodine Deficiency will include: a special prorgramme for the iodization of animal food according to european standard, increased rate of pregnant women additionally supplemented with iodine, strengthening public awarness on necessary increase of milk consumption especially in pregnancy and in children and continouse monitoring system of biologic effects and technologic quality of the model of iodine prophylaxis. PMID:16335675

  17. Iodine in food- and dietary supplement-composition databases.

    PubMed

    Pehrsson, Pamela R; Patterson, Kristine Y; Spungen, Judith H; Wirtz, Mark S; Andrews, Karen W; Dwyer, Johanna T; Swanson, Christine A

    2016-09-01

    The US Food and Drug Administration (FDA) and the Nutrient Data Laboratory (NDL) of the USDA Agricultural Research Service have worked independently on determining the iodine content of foods and dietary supplements and are now harmonizing their efforts. The objective of the current article is to describe the harmonization plan and the results of initial iodine analyses accomplished under that plan. For many years, the FDA's Total Diet Study (TDS) has measured iodine concentrations in selected foods collected in 4 regions of the country each year. For more than a decade, the NDL has collected and analyzed foods as part of the National Food and Nutrient Analysis Program; iodine analysis is now being added to the program. The NDL recently qualified a commercial laboratory to conduct iodine analysis of foods by an inductively coupled plasma mass spectrometry (ICP-MS) method. Co-analysis of a set of samples by the commercial laboratory using the ICP-MS method and by the FDA laboratory using its standard colorimetric method yielded comparable results. The FDA recently reviewed historical TDS data for trends in the iodine content of selected foods, and the NDL analyzed samples of a limited subset of those foods for iodine. The FDA and the NDL are working to combine their data on iodine in foods and to produce an online database that can be used for estimating iodine intake from foods in the US population. In addition, the NDL continues to analyze dietary supplements for iodine and, in collaboration with the NIH Office of Dietary Supplements, to publish the data online in the Dietary Supplement Ingredient Database. The goal is to provide, through these 2 harmonized databases and the continuing TDS focus on iodine, improved tools for estimating iodine intake in population studies. PMID:27534627

  18. Xenon and iodine reveal multiple distinct exotic xenon components in Efremovka "nanodiamonds"

    NASA Astrophysics Data System (ADS)

    Gilmour, J. D.; Holland, G.; Verchovsky, A. B.; Fisenko, A. V.; Crowther, S. A.; Turner, G.

    2016-03-01

    We identify new xenon components in a nanodiamond-rich residue from the reduced CV3 chondrite Efremovka. We demonstrate for the first time that these, and the previously identified xenon components Xe-P3 and Xe-P6, are associated with elevated I/Xe ratios. The 129I/127I ratio associated with xenon loss from these presolar compositions during processing on planetesimals in the early solar system was (0.369 ± 0.019) × 10-4, a factor of 3-4 lower than the canonical value. This suggests either incorporation of iodine into carbonaceous grains before the last input of freshly synthesized 129I to the solar system's precursor material, or loss of noble gases during processing of planetesimals around 30 Myr after solar system formation. The xenon/iodine ratios and model closure ages were revealed by laser step pyrolysis analysis of a neutron-irradiated, coarse-grained nanodiamond separate. Three distinct low temperature compositions are identified by characteristic I/Xe ratios and 136Xe/132Xe ratios. There is some evidence of multiple compositions with distinct I/Xe ratios in the higher temperature releases associated with Xe-P6. The presence of iodine alongside Q-Xe and these components in nanodiamonds constrains the pathway by which extreme volatiles entered the solid phase and may facilitate the identification of their carriers. There is no detectable iodine contribution to the presolar Xe-HL component, which is released at intermediate temperatures; this suggests a distinct trapping process. Releases associated with the other components all include significant contributions of 128Xe produced from iodine by neutron capture during reactor irradiation. We propose a revised model relating the origin of Xe-P3 (which exhibits an s-process deficit) through a "Q-process" to the Q component (which makes the dominant contribution to the heavy noble gas budget of primitive material). The Q-process incorporates noble gases and iodine into specific carbonaceous phases with mass

  19. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    SciTech Connect

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  20. Efficient flashlamp-pumped IBr laser

    NASA Technical Reports Server (NTRS)

    Zapata, L. E.; De Young, R. J.

    1985-01-01

    The operating characteristics and scaling parameters of a flashlamp-pumped, 4-m-long IBr laser were investigated to further evaluate its potential as a solar-pumped laser. A peak power of 3 kW/sq cm at 2.7 microns was achieved at 4-Torr IBr pressure. A gain of 0.07 per m was measured at a maximum capacitor discharge energy of 4 kJ. The threshold input power necessary for lasing was found to decrease by a factor of 4 and the laser pulse width increased fourfold as the active gain length was increased from 1 to 4 m. A maximum pulse width of 120 microseconds was achieved with 10-Torr argon diluent added to 4-Torr IBr. Quenching of the excited state by the parent molecule was shown to be unimportant for pressures less than 4-Torr IBr. An intrinsic efficiency in the range of 12 percent has been measured for flashlamp-pumped IBr.

  1. Iodine and thyroid hormones during pregnancy and postpartum.

    PubMed

    Pérez-López, Faustino R

    2007-07-01

    Iodine is a trace element essential for synthesis of the thyroid hormones, triiodothyronine and thyroxine. These hormones play a vital role in the early growth and development stages of most organs, especially the brain. The World Health Organization (WHO) has declared that, after famine, iodine deficiency is the most avoidable cause of cerebral lesions including different degrees of mental retardation and cerebral paralysis. The main function of iodine in vertebrates is to interact with the thyroid hormones. During pregnancy sufficient quantities of iodine are required to prevent the appearance of hypothyroidism, trophoblastic and embryonic or fetal disorders, neonatal and maternal hypothyroidism, and permanent sequelae in infants. Thyroid hormone receptors and iodothyronine deiodinases are present in placenta and central nervous tissue of the fetus. A number of environmental factors influence the epidemiology of thyroid disorders, and even relatively small abnormalities and differences in the level of iodine intake in a population have profound effects on the occurrence of thyroid abnormalities. The prevalence of disorders related to iodine deficit during pregnancy and postpartum has increased. Iodine supplementation is an effective measure in the case of pregnant and lactating women. However, it is not implemented and the problem is still present even in societies with theoretically advanced health systems. During pregnancy and postpartum, the WHO recommends iodine intake be increased to at least 200 microg/day. Side-effects provoked by iodine supplementation are rare during pregnancy at the recommended doses. PMID:17701774

  2. Mission and System Advantages of Iodine Hall Thrusters

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Szabo, James; Pote, Bruce; Oleson, Steve; Kamhawi, Hani

    2014-01-01

    The exploration of alternative propellants for Hall thrusters continues to be of interest to the community. Investments have been made and continue for the maturation of iodine based Hall thrusters. Iodine testing has shown comparable performance to xenon. However, iodine has a higher storage density and resulting higher ?V capability for volume constrained systems. Iodine's vapor pressure is low enough to permit low-pressure storage, but high enough to minimize potential adverse spacecraft-thruster interactions. The low vapor pressure also means that iodine does not condense inside the thruster at ordinary operating temperatures. Iodine is safe, it stores at sub-atmospheric pressure, and can be stored unregulated for years on end; whether on the ground or on orbit. Iodine fills a niche for both low power (<1kW) and high power (>10kW) electric propulsion regimes. A range of missions have been evaluated for direct comparison of Iodine and Xenon options. The results show advantages of iodine Hall systems for both small and microsatellite application and for very large exploration class missions.

  3. Recent experiences with iodine water disinfection in Shuttle

    NASA Technical Reports Server (NTRS)

    Gibbons, Randall E.; Flanagan, David T.; Schultz, John R.; Sauer, Richard L.; Slezak, Terry N.

    1990-01-01

    Microbial proliferation in the STS potable water system is prevented by maintaining a 2-5 ppm iodine residual. The iodine is added to fuel cell water by an iodinated ion exchange resin in the Microbial Check Valve (MCV). Crew comments indicated excessive iodine in the potable water. To better define the problem, a method of in-flight iodine analysis was developed. Inflight analysis during STS-30 and STS-28 indicated iodine residuals were generally in the 9-13 ppm range. It was determined that the high iodine residual was caused by MCV influent temperatures in excess of 120 F. This is well above the MCV operating range of 65-90 F. The solution to this problem was to develop a resin suitable for the higher temperatures. Since 8 months were required to formulate a MCV resin suitable for the higher temperatures, a temporary solution was necessary. Two additional MCV's were installed on the chilled and ambient water lines leading into the galley to remove the excess iodine. These reduced the iodine residual to 3-4 ppm during STS-33, STS-34, STS-36 and STS-32. A high-temperature resin was formulated and initially flown on STS-31.

  4. Urinary iodine percentile ranges in the United States

    PubMed Central

    Soldin, Offie Porat; Soldin, Steven J.; Pezzullo, John C.

    2013-01-01

    Background The status of iodine nutrition of a population can be determined by measurement of urinary iodine concentrations since it is thought to indicate dietary iodine intake. Normally, these results are compared to population-based criteria, since there are no reference ranges for urinary iodine. Objective To determine the percentile ranges for urinary iodide (UI) concentrations in normal individuals in the United States. Materials and methods The third National Health and Nutrition Examination Survey (NHANES III) (1988–1994) database of the civilian, non-institutionalized, iodine-sufficient US population was used. The 2.5th to 97.5th percentile ranges for urinary iodine and for urinary iodine per gram creatinine ratio (UI/Cr) (μg/g) were calculated for females and males, 6–89 years of age, each stratified by age groups. Results and conclusions We calculated the percentile ranges for urinary iodine. After exclusions of subjects with goiter or thyroid disease, the study sample included 21,530 subjects; 10,439 males and 11,091 females. For women of childbearing age (14–44 years), urinary iodine concentration 2.5th to 97.5th percentiles are 1.8–65 μg/dl or 36–539 μg/g creatinine. For pregnant women, the ranges are 4.2–55 μg/dl or 33–535 μg/g creatinine. PMID:12559616

  5. Selenium deficiency mitigates hypothyroxinemia in iodine-deficient subjects.

    PubMed

    Vanderpas, J B; Contempré, B; Duale, N L; Deckx, H; Bebe, N; Longombé, A O; Thilly, C H; Diplock, A T; Dumont, J E

    1993-02-01

    Studies were performed to assess the role of combined selenium and iodine deficiency in the etiology of endemic myxedematous cretinism in a population in Zaire. One effect of selenium deficiency may be to lower glutathione peroxidase activity in the thyroid gland, thus allowing hydrogen peroxide produced during thyroid hormone synthesis to be cytotoxic. In selenium-and-iodine-deficient humans, selenium supplementation may aggravate hypothyroidism by stimulating thyroxin metabolism by the selenoenzyme type I iodothyronine 5'-deiodinase. Selenium supplementation is thus not indicated without iodine or thyroid hormone supplementation in cases of combined selenium and iodine deficiencies. PMID:8427203

  6. Medical effects of iodine disinfection products in spacecraft water

    NASA Technical Reports Server (NTRS)

    Sauer, Richard L.; Janik, Daniel S.; Thorstenson, Yvonne R.

    1987-01-01

    Various iodination products (IDPs), including iodinated and iodine-induced new compounds, will be present in the iodine-disinfected water that is expected to be used by crews on the NASA Space Station and on long duration missions. The metabolic intermediaries created by such a process may be more important to crew health than the parent IDPs, and reclamation and recycling may be expected to produce additional products. These medical effects may be expressed in crews as hypersensitivity, allergic, acute toxic, and chronic toxic reactions, as well as modifications of immune system response.

  7. Screening for thyroid disease and iodine deficiency.

    PubMed

    Eastman, Creswell J

    2012-02-01

    The high global prevalence of iodine deficiency and autoimmune thyroid disorders and the mental and physical consequences of these disorders creates a huge human and economic burden that can be prevented, in large part, by early detection and appropriate preventative or therapeutic measures. The availability of sophisticated, sensitive and accurate laboratory testing procedures provides an efficient and effective platform for the application of screening for these disorders. Measurement of urine iodine concentration (UIC) in school children or pregnant women is the recommended indicator for screening populations for iodine deficiency. The severity of the iodine deficiency is classified according to the UIC. Measurement of serum thyrotropin (TSH) as an indicator for population iodine deficiency is used only in neonates and is supplementary to UIC screening. Other indicators such as goitre rates, thyroid function and serum thyroglobulin levels are useful adjunctive but not frontline process indicators. The human and economic benefits of screening for congenital hypothyroidism by measurement of heel-prick TSH have been well documented and justify its universal application. Using this measurement for monitoring population iodine intake is recommended by the World Health Organization but further validation is required before it can be universally recommended. Subclinical thyroid dysfunction is readily detected by current highly sensitive serum TSH assays and its prevalence appears to increase with age, varies with iodine intake and ethnicity and may occur in up to 20% of older age people. Subclinical hyperthyroidism is the less common disorder and screening cannot be justified because of its low prevalence and minimal or insignificant clinical effects. The argument for screening for subclinical hypothyroidism in middle-aged and older women is stronger but lacks evidence of benefit from randomised controlled trials or cost benefit analyses of therapeutic intervention, so

  8. Method for the simultaneous preparation of Radon-211, Xenon-125, Xenon-123, Astatine-211, Iodine-125 and Iodine-123

    DOEpatents

    Mirzadeh, Saed; Lambrecht, Richard M.

    1987-01-01

    A method for simultaneously preparing Radon-211, Astatine-211, Xenon-125, Xenon-123, Iodine-125 and Iodine-123 in a process that includes irradiating a fertile metal material then using a one-step chemical procedure to collect a first mixture of about equal amounts of Radon-211 and Xenon-125, and a separate second mixture of about equal amounts of Iodine-123 and Astatine-211.

  9. Iodine deficiency among Belgian pregnant women not fully corrected by iodine-containing multivitamins: a national cross-sectional survey.

    PubMed

    Vandevijvere, Stefanie; Amsalkhir, Sihame; Mourri, Ahmed Bensouda; Van Oyen, Herman; Moreno-Reyes, Rodrigo

    2013-06-28

    Low iodine intake during pregnancy may cause thyroid dysfunction in pregnant women and their newborn. In the present study, iodine status among a nation-wide representative sample of Belgian pregnant women in the first and third trimester of pregnancy was determined, and determinants of iodine status were assessed 1 year after the introduction of bread fortified with iodised salt. The women were selected according to a multistage proportionate-to-size sampling design. Urine samples were collected and a general questionnaire was completed face to face with the study nurse. The median urinary iodine concentration (UIC) among pregnant women (n 1311) was 124.1mg/l and 122.6 mg/g creatinine when corrected for urinary creatinine. The median UIC in the first trimester (118.3 mg/l) was significantly lower than that in the third trimester (131.0 mg/l) but significantly higher than among non-pregnant women (84.8 mg/l). Iodine-containing supplement intake was reported by 60.8% of the women and 57.4% of the women took this supplement daily. The risk of iodine deficiency was significantly higher in younger women, in women not taking iodine-containing supplements, with low consumption of milk and dairy drinks and during autumn. Women with a higher BMI had a higher risk of iodine deficiency but the risk was lower in women who reported alcohol consumption. The median UIC during pregnancy indicates iodine deficiency in Belgium and some women are at a higher risk of deficiency. The current low iodine intake in women of childbearing age precludes the correction of iodine deficiency in pregnant women supplemented with multivitamins containing 150 mg iodine as recommended. PMID:23084115

  10. Method for gettering organic, inorganic and elemental iodine in aqueous solutions

    DOEpatents

    Beahm, Edward C.; Shockley, William E.

    1990-07-03

    A process for the removal of iodine from aqueous solutions, particularly the trapping of radioactive iodine to mitigate damage resulting from accidents or spills associated with nuclear reactors, by exposing the solution to well dispersed silver carbonate which reacts with the iodine and iodides, thereby gettering iodine and iodine compounds from solution. The iodine is not only removed from solution but also from the contiguous vapor.

  11. Method for gettering organic, inorganic and elemental iodine in aqueous solutions

    DOEpatents

    Beahm, Edward C.; Shockley, William E.

    1990-01-01

    A process for the removal of iodine from aqueous solutions, particularly the trapping of radioactive iodine to mitigate damage resulting from accidents or spills associated with nuclear reactors, by exposing the solution to well dispersed silver carbonate which reacts with the iodine and iodides, thereby gettering iodine and iodine compounds from solution. The iodine is not only removed from solution but also from the contiguous vapor.

  12. Controlled iodine release from polyurethane sponges for water decontamination.

    PubMed

    Aviv, Oren; Laout, Natalia; Ratner, Stanislav; Harik, Oshrat; Kunduru, Konda Reddy; Domb, Abraham J

    2013-12-28

    Iodinated polyurethane (IPU) sponges were prepared by immersing sponges in aqueous/organic solutions of iodine or exposing sponges to iodine vapors. Iodine was readily adsorbed into the polymers up to 100% (w/w). The adsorption of iodine on the surface was characterized by XPS and SEM analyses. The iodine loaded IPU sponges were coated with ethylene vinyl acetate (EVA), in order to release iodine in a controlled rate for water decontamination combined with active carbon cartridge, which adsorbs the iodine residues after the microbial inactivation. The EVA coated IPU were incorporated in a water purifier and tested for iodine release to water and for microbial inactivation efficiency according to WQA certification program against P231/EPA for 250l, using 25l a day with flow rate of 6-8min/1l. The antimicrobial activity was also studied against Escherichia coli and MS2 phage. Bacterial results exceeded the minimal requirement for bacterial removal of 6log reduction throughout the entire lifespan. At any testing point, no bacteria was detected in the outlet achieving more than 7.1 to more than 8log reduction as calculated upon the inlet concentration. Virus surrogate, MS2, reduction results varied from 4.11log reduction under tap water, and 5.11log reduction under basic water (pH9) to 1.32 for acidic water (pH5). Controlled and stable iodine release was observed with the EVA coated IPU sponges and was effective in deactivating the bacteria and virus present in the contaminated water and thus, these iodinated PU systems could be used in water purification to provide safe drinking water. These sponges may find applications as disinfectants in medicine. PMID:24096017

  13. Iodine Sorbent Performance in FY 2012 Deep Bed Tests

    SciTech Connect

    Nick Soelberg; Tony Watson

    2012-08-01

    Nuclear fission results in the production of fission products and activation products, some of which tend to be volatile during used fuel reprocessing and evolve in gaseous species into the reprocessing facility off-gas systems. Analyses have shown that I-129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Iodine capture is an important aspect of the Separations and Waste Forms Campaign Off-gas Sigma Team (Jubin 2011, Pantano 2011). Deep-bed iodine sorption tests for both silver-functionalized Aerogel and silver zeolite sorbents were performed during Fiscal Year 2012. These tests showed that: • Decontamination factors were achieved that exceed reasonably conservative estimates for DFs needed for used fuel reprocessing facilities in the U.S. to meet regulatory requirements for I-129 capture. • Silver utilizations approached or exceeded 100% for high inlet gas iodine concentrations, but test durations were not long enough to approach 100% silver utilization for lower iodine concentrations. • The depth of the mass transfer zone was determined for both low iodine concentrations (under 10 ppmv) and for higher iodine concentrations (between 10-50 ppmv); the depth increases over time as iodine is sorbed. • These sorbents capture iodine by chemisorption, where the sorbed iodine reacts with the silver to form very non-volatile AgI. Any sorbed iodine that is physisorbed but not chemically reacted with silver to form AgI might not be tightly held by the sorbent. The portion of sorbed iodine that tends to desorb because it is not chemisorbed (reacted to form AgI) is small, under 1%, for the AgZ tests, and even smaller, under 0.01%, for the silver-functionalized Aerogel.

  14. Dietary evaluation of a low-iodine diet in Korean thyroid cancer patients preparing for radioactive iodine therapy in an iodine-rich region

    PubMed Central

    Ju, Dal Lae; Park, Young Joo; Paik, Hee-Young; Kim, Min-Ji; Park, Seonyeong; Jung, Kyong Yeun; Kim, Tae Hyuk; Choi, Hun Sung

    2016-01-01

    BACKGROUND/OBJECTIVES Despite the importance of a low-iodine diet (LID) for thyroid cancer patients preparing for radioactive iodine (RAI) therapy, few studies have evaluated dietary intake during LID. This study evaluated the amount of dietary iodine intake and its major food sources during a typical diet and during LID periods for thyroid cancer patients preparing for RAI therapy, and examined how the type of nutrition education of LID affects iodine intake. SUBJECTS/METHODS A total of 92 differentiated thyroid cancer patients with total thyroidectomy were enrolled from Seoul National University Hospital. All subjects completed three days of dietary records during usual and low-iodine diets before 131I administration. RESULTS The median iodine intake was 290 µg/day on the usual diet and 63.2 µg/day on the LID. The major food groups during the usual diet were seaweed, salted vegetables, fish, milk, and dairy products and the consumption of these foods decreased significantly during LID. The mean energy intake on the LID was 1,325 kcal, which was 446 kcal lower than on the usual diet (1,771 kcal). By avoiding iodine, the intake of most other nutrients, including sodium, was significantly reduced during LID (P < 0.005). Regarding nutritional education, intensive education was more effective than a simple education at reducing iodine intake. CONCLUSION Iodine intake for thyroid cancer patients was significantly reduced during LID and was within the recommended amount. However, the intake of most other nutrients and calories was also reduced. Future studies are needed to develop a practical dietary protocol for a LID in Korean patients. PMID:27087900

  15. Theoretical studies of solar lasers and converters

    NASA Technical Reports Server (NTRS)

    Heinbockel, John

    1988-01-01

    The geometry and setup for the n-C3F7I iodine laser are illustrated. The mathematical modeling of this system is described. The chemical kinetics are summarized. A sensitivity analysis was performed on the parameters occurring in the differential equations describing the chemical kinetics.

  16. Intermolecular Cyclopropanation of Styrenes Using Iodine and Visible Light via Carbon-Iodine Bond Cleavage.

    PubMed

    Usami, Kaoru; Nagasawa, Yoshitomo; Yamaguchi, Eiji; Tada, Norihiro; Itoh, Akichika

    2016-01-01

    The intermolecular cyclopropanation of aromatic olefins with activated methylene compounds using iodine and visible light irradiation was described. This reaction proceeds under rare-metal-free conditions. Styrenes with various substituted groups (alkyl and electron-withdrawing groups) provided corresponding cyclopropanes in moderate to good yields. PMID:26654114

  17. Iodine deficiency, other trace elements, and goitrogenic factors in the etiopathogeny of iodine deficiency disorders (IDD).

    PubMed

    Thilly, C H; Vanderpas, J B; Bebe, N; Ntambue, K; Contempre, B; Swennen, B; Moreno-Reyes, R; Bourdoux, P; Delange, F

    1992-01-01

    Severe goiter, cretinism, and the other iodine deficiency disorders (IDD) have their main cause in the lack of availability of iodine from the soil linked to a severe limitation of food exchanges. Apart from the degrees of severity of the iodine deficiency, the frequencies and symptomatologies of cretinism and the other IDD are influenced by other goitrogenic factors and trace elements. Thiocyanate overload originating from consumption of poorly detoxified cassava is such that this goitrogenic factor aggravates a relative or a severe iodine deficiency. Very recently, a severe selenium deficiency has also been associated with IDD in the human population, whereas in animals, it has been proven to play a role in thyroid function either through a thyroidal or extrathyroidal mechanism. The former involves oxidative damages mediated by free radicals, whereas the latter implies an inhibition of the deiodinase responsible for the utilization of T4 into T3. One concludes that: 1. Goiter has a multifactorial origin; 2. IDD are an important public health problem; and 3. IDD are a good model to study the effects of other trace elements whose actions in many human metabolisms have been somewhat underestimated. PMID:1375059

  18. Electrophilic iodination: a gateway to high iodine compounds and energetic materials.

    PubMed

    Chand, Deepak; He, Chunlin; Mitchell, Lauren A; Parrish, Damon A; Shreeve, Jean'ne M

    2016-09-21

    A large number of iodine atoms can be introduced into a single molecule in a one-pot reaction using trifluoroperacetic acid-mediated electrophilic iodination methodology. The scope of this reaction was investigated extensively using several pyrazole substrates which resulted in nine polyiodo pyrazole compounds with iodine content as high as 80%. This synthetic methodology was also utilized successfully for iodination of benzimidazoles. Tetraiodobenzimidazole was nitrated with 100% nitric acid to give a high yield of 4,5,6,7-tetranitro-1H-benzimidazol-2(3H)-one (14). All of these materials were fully characterized and compounds 5, 9, 10 and 14 were confirmed further with single crystal X-ray analysis. High density, positive oxygen balance, and very good impact sensitivity values characterize 14. For the first time, two 1,2,5-oxadiazole-N-oxide rings were introduced into a benzimidazole ring (11) which remarkably improves the stability of oxadiazole-N-oxide compounds. PMID:27510578

  19. Staging in polyacetylene-iodine conductors

    NASA Astrophysics Data System (ADS)

    Baughman, R. H.; Murthy, N. S.; Miller, G. G.; Shacklette, L. W.

    1983-07-01

    Evidence is presented for the existence of highly conducting polyacetylene complexes with structures related to high-stage graphite, as well as structures related to first-stage graphite. X-ray diffraction measurements on polyacetylene-iodine complexes indicate equatorial lines at 7.7-8.0 and 13.8-14.3 Å. The shorter spacing arises in part from a structure in which iodine-rich planes alternate with planes of polyacetylene chains. The longer spacing, which disappears upon atmospheric exposure, is consistent with a structure analogous to third-stage graphite in which dopant-rich planes are separated by three close-packed planes of polyacetylene chains. The third-stage complex can be viewed as a perturbation of the structure of undoped polyacetylene, with the region between dopant layers consisting essentially of a one unit cell thickness of the parent polymer structure. Packing calculations for this model, in which a linear column of anions (I3- and/or I5-) displaces either every chain or every other chain in the dopant-rich layer, provide an interlayer spacing which is equal to that observed. Evidence consistent with third-stage structures (with both fractional occupation and complete occupation of the dopant plane) is also found by reexamination of published sorption data, which provides slope changes at close to the calculated limiting compositions for these structures [(CHI0.056)x and (CHI0.13)x]. However, a first-stage structure with alternating dopant arrays and polymer chains in the dopant plane [for which (CHI0.13)x is calculated] provides a better explanation for the second slope change, as well as for the composition obtained under dynamic vacuum, (CHI0.14)x. These results for iodine complexes are compared with those derived for the group VA halide complexes of polyacetylene.

  20. Iodine nutritional status in Uttarakhand State, India

    PubMed Central

    Sareen, Neha; Kapil, Umesh; Nambiar, Vanisha; Pandey, Ravindra Mohan; Khenduja, Preetika

    2016-01-01

    Introduction: Uttarakhand (UK) state is a known endemic region to iodine deficiency (ID). Objective: To assess the current status of iodine nutrition in a population of UK. Methodology: Three districts, namely Udham Singh Nagar (USN), Nainital (N), and Pauri Garhwal (PG) were selected. In each district, 30 clusters were identified by utilizing the population proportional to size cluster sampling methodology. Total of 6143 school age children (SAC) (USN; 1807, N; 2269, PG: 2067), 5430 adolescent girls (AGs) (USN; 1823, N; 1811, PG: 1796), 1727 pregnant mothers (PMs) (USN; 632, N; 614, PG: 481), and 2013 Neonates (USN; 649, N; 670, PG: 694), were included in the study. Clinical examination of thyroid of each child, AG and PM was conducted. Spot urine and salt samples were collected from children, AGs and PMs. Cord blood samples were collected from neonates for estimation of thyroid stimulating hormone (TSH). Results: In SAC, total goiter rate (TGR) was 13.2% (USN), 15.9% (N), and 16.8% (PG). Median urinary iodine concentration (UIC) level was 150 μg/l (USN), 125 μg/l (N), and 115 μg/l (PG). In AGs, TGR was 6.8% (USN), 8.2% (N) and 5.6% (PG). Median UIC level was 250 μg/l (USN), 200 μg/l (N), and 183 μg/l (PG). In PMs, TGR was 16.1% (USN), 20.2% (N), and 24.9% (PG). Median UIC level was 124 μg/l (USN), 117.5 μg/l (N) and 110 μg/l (PG), respectively. In Neonates, TSH levels of >5 mIU/L were found in 55.3 (USN), 76.4 (N) and 72.8 (PG) percent of neonates. Conclusion: UIC level in PMs and TSH levels among neonates indicate the prevalence of ID in three districts surveyed. PMID:27042411

  1. Engineering planetary lasers for interstellar communication. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Sherwood, Brent

    1988-01-01

    Transmitting large amounts of data efficiently among neighboring stars will vitally support any eventual contact with extrasolar intelligence, whether alien or human. Laser carriers are particularly suitable for high-quality, targeted links. Space laser transmitter systems designed by this work, based on both demonstrated and imminent advanced space technology, could achieve reliable data transfer rates as high as 1 kb/s to matched receivers as far away as 25 pc, a distance including over 700 approximately solar-type stars. The centerpiece of this demonstration study is a fleet of automated spacecraft incorporating adaptive neural-net optical processing active structures, nuclear electric power plants, annular momentum control devices, and ion propulsion. Together the craft sustain, condition, modulate, and direct to stellar targets an infrared laser beam extracted from the natural mesospheric, solar-pumped, stimulated CO2 emission recently discovered at Venus. For a culture already supported by mature interplanetary industry, the cost of building planetary or high-power space laser systems for interstellar communication would be marginal, making such projects relevant for the next human century. Links using high-power lasers might support data transfer rates as high as optical frequencies could ever allow. A nanotechnological society such as we might become would inevitably use 10 to the 20th power b/yr transmission to promote its own evolutionary expansion out of the galaxy.

  2. [Iodinated contrast agents used in Radiology].

    PubMed

    Ramírez Ribelles, C; Sánchez Fuster, M A; Pamies Guilabert, J

    2014-06-01

    Iodinated contrast media are widely used in Radiology practices with a very low rate of adverse effects, being contrast-induced nephropathy the most serious one. In the majority of cases it is temporary and reversible, even though it can increase the inhospital morbidity and mortality in patients with risk factors. We will describe the various measures of prevention, being hydration and use of non-ionic contrast low osmolality those which have demonstrated greater effectiveness. Precautions to be taken in some risk situations, as patients treated with metformin or with impaired renal function, are also discussed. PMID:25267147

  3. The addition of iodine to tetramethylammonium iodide

    USGS Publications Warehouse

    Foote, H.W.; Fleischer, M.

    1953-01-01

    The system tetramethylammonium iodide-iodine-toluene has been studied by the solubility method at 6 and at 25??. The compounds (CH3)4NI3, (CH3)4NI5 and (CH3)4NI11 were found to be stable phases at both temperatures. In addition, the compound (CH3)4NI10 was found at 6?? and the compound (CH3)4NI9 at 25??. The dissociation pressures of the compounds at these temperatures were calculated from the solubility data.

  4. Viscosity of high-temperature iodine

    NASA Technical Reports Server (NTRS)

    Kang, Steve H.; Kunc, Joseph A.

    1991-01-01

    The viscosity coefficient of iodine in the temperature range 500 - 3000 K is calculated. Because of the low dissociation energy of the I2 molecules, the dissociation degree of the gas increases quickly with temperature, and I + I2 and I + I collisions must be taken into account in calculation of viscosity at temperatures greater than 1000 deg. Several possible channels for atom-atom interaction are considered, and the resulting collision integrals are averaged over all the important channels. It is also shown that the rigid-sphere model is inaccurate in predictions of the viscosity.

  5. Improved iodine radiolabels for monoclonal antibody therapy.

    PubMed

    Stein, Rhona; Govindan, Serengulam V; Mattes, M Jules; Chen, Susan; Reed, Linda; Newsome, Guy; McBride, Bill J; Griffiths, Gary L; Hansen, Hans J; Goldenberg, David M

    2003-01-01

    A major disadvantage of (131)iodine (I)-labeled monoclonal antibodies (MAbs) for radioimmunotherapy has been the rapid diffusion of iodotyrosine from target cells after internalization and catabolism of the radioiodinated MAbs. We recently reported that a radioiodinated, diethylenetriaminepentaacetic acid-appended peptide, designated immunomedics' residualizing peptide 1 (IMP-R1), was a residualizing iodine label that overcame many of the limitations that had impeded the development of residualizing iodine for clinical use. To determine the factors governing the therapeutic index of the labeled MAb, as well as the factors required for production of radioiodinated MAb in high yield and with high specific activity, variations in the peptide structure of IMP-R1 were evaluated. A series of radioiodinated, diethylenetriaminepentaacetic acid-appended peptide moieties (IMP-R1 through IMP-R8) that differed in overall hydrophilicity and charge were compared. Radioiodinations of the peptides followed by conjugations to disulfide-reduced RS7 (an anti-epithelial glycoprotein-1 MAb) furnished radioimmunoconjugates in good overall incorporations, with immunoreactivities comparable to that of directly radioiodinated RS7. Specific activities of up to 8 mCi/mg and yields > 80% have been achieved. In vitro processing experiments showed marked increases in radioiodine retention with all of the adducts; radioiodine retention at 45 h was up to 86% greater in cells than with directly iodinated RS7. Each of the (125)I-peptide-RS7 conjugates was compared with (131)I-RS7 (labeled by the chloramine-T method) in paired-label biodistribution studies in nude mice bearing human lung tumor xenografts. All of the residualizing substrates exhibited significantly enhanced retention in tumor in comparison to directly radioiodinated RS7, but the nontarget uptakes differed significantly among the residualizing labels. The best labels were IMP-R4 and IMP-R8, showing superior tumor-to-non-tumor ratios

  6. Treatment with Iodine in Pregnant Rats with Marginal Iodine Deficiency Improves Cell Migration in the Developing Brain of the Progeny.

    PubMed

    Zhang, Le; Zhai, Xiaodan; Liu, Yuhui; Li, Jing; Shan, Zhongyan; Teng, Weiping

    2016-05-01

    Marginal iodine deficiency is a common health problem in pregnant women. Epidemiological and animal studies had shown that marginally maternal iodine deficiency could cause the mild changes of maternal thyroid function, eventually lead to a negative effect on neurodevelopment. But the underlying mechanisms responsible for the neurological impairment remain unclear. The aim of this study is to explore whether marginally maternal iodine deficiency could produce subtle changes in cell migration and cognitive function of offspring, and the optimal time of giving intervention to minimize the adverse effects. In the present study, we established a marginal iodine deficiency model, and iodine supplement was performed on pre-pregnancy (PP), G13 (gestation day 13), and postnatal day 0 (P0). Our data showed that there were changes in the cytoarchitecture and the percentage of bromodeoxyuridine (BrdU)-labeled cells in the cerebral cortex in marginal iodine deficiency rats. The Reelin expression was significantly lower, but Tenascin-C was higher in the cerebral cortex of marginal iodine deficiency group on P7 than the normal group, respectively. When iodine supplement, especially before G13 could reverse the abnormal expression of the two proteins involved in cell migration, which was consistent with the results of Morris Water Maze test. The three intervention groups had shorter escape latencies than the marginal iodine deficiency rats. The earlier that iodine is supplied, the better behavior performance would reach. Our findings suggested that iodine supplement in early stage of pregnancy could improve the cell migration of cerebral cortex and neurodevelopment of offspring. PMID:25963726

  7. [Effects of the iodine deficiency on intellectual variables among children].

    PubMed

    Muela Martínez, José Antonio; García León, Ana; Torres Barahona, Rosario; Santiago Fernández, Piedad; Sóriguer Escofet, Federico

    2008-05-01

    An association between severe iodine deficiency and poor mental development has been found in many studies. We examined the relationship between moderate or mild iodine deficiency and intellectual capacity in order to determine whether problems common to severe iodine deficiency (including mental retardation) also emerge in a more subtle form. We also wished to know whether the classic methodology (comparing iodine-deficient zones with nondeficient zones) is the most adequate, and propose to combine this grouping by zones with urinary iodine presented by individuals in each zone. We measured IQ, manipulative and verbal capacity, attention, visual motor ability and disruptive behaviour, variables that have barely been studied in this kind of investigations. The sample comprised 760 schoolchildren from the province of Jaén (southern Spain). Our results show that children with low levels of iodine intake and with urinary iodine concentration lower than 100 microg/litre had a lower IQ and displayed more disruptive behaviour than children with high levels of the criteria. The other variables were not associated with iodine deficiency. PMID:18413091

  8. Iodine Deficiency in Australia: Be Alarmed. Opinions & Perspectives

    ERIC Educational Resources Information Center

    McElduff, Aidan; Beange, Helen

    2004-01-01

    Iodine deficiency, the leading preventable cause of intellectual impairment in the world (World Health Organization, 1999), has reappeared in Australia. Recently, we identified the re-emergence of iodine deficiency in Sydney (Gunton, Hams, Fiegert & McElduff, 1999). This has been confirmed locally (Li, Ma, Boyages & Eastman, 2001) and…

  9. Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes.

    PubMed

    Aakre, Inger; Strand, Tor A; Bjøro, Trine; Norheim, Ingrid; Barikmo, Ingrid; Ares, Susana; Alcorta, Marta Duque; Henjum, Sigrun

    2016-01-01

    Iodine excess may impair thyroid function and trigger adverse health consequences for children. This study aims to describe iodine status among breastfed infants with high iodine exposure in the Saharawi refugee camps Algeria, and further assess thyroid function and iodine status among the children three years later. In 2010, a cross-sectional study among 111 breastfed children aged 0-6 months was performed (baseline study). In 2013, a second cross-sectional study (follow-up study) was conducted among 289 children; 213 newly selected and 76 children retrieved from baseline. Urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were measured at baseline. UIC, thyroid hormones and serum thyroglobulin (Tg) were measured at follow-up. At baseline and follow-up, 88% and 72% had excessive iodine intakes (UIC ≥ 300 µg/L), respectively. At follow-up, 24% had a thyroid hormone disturbance and/or elevated serum Tg, including 9% with subclinical hypothyroidism (SCH), 4% with elevated fT3 and 14% with elevated Tg. Children with SCH had poorer linear growth and were more likely to be underweight than the children without SCH. Excessive iodine intakes and thyroid disturbances were common among children below four years of age in our study. Further, SCH seemed to be associated with poor growth and weight. PMID:27367720

  10. Acute Iodine Toxicity From a Suspected Oral Methamphetamine Ingestion

    PubMed Central

    Bulloch, Marilyn N

    2014-01-01

    BACKGROUND Iodine is a naturally occurring element commercially available alone or in a multitude of products. Iodine crystals and iodine tincture are used in the production of methamphetamine. Although rarely fatal, iodine toxicity from oral ingestion can produce distressing gastrointestinal symptoms and systemic symptoms, such as hypotension and tachycardia, from subsequent hypovolemia. OBJECTIVE The objective of this case report is to describe a case of iodine toxicity from suspected oral methamphetamine ingestion. CASE REPORT A male in his early 20’s presented with gastrointestinal symptoms, chills, fever, tachycardia, and tachypnea after orally ingesting a substance suspected to be methamphetamine. The patient had elevated levels of serum creatinine, liver function tests, and bands on arrival, which returned to within normal limits by day 4 of admission. Based on the patient’s narrow anion gap, halogen levels were ordered on day 3 and indicated iodine toxicity. This is thought to be the first documented case of iodine toxicity secondary to suspected oral methamphetamine abuse. CONCLUSION Considering that the incidence of methamphetamine abuse is expected to continue to rise, clinicians should be aware of potential iodine toxicity in a patient with a history of methamphetamine abuse. PMID:25452705

  11. Determination of iodine to compliment mass spectrometric measurements

    SciTech Connect

    Hohorst, F.A.

    1994-11-01

    The dose of iodine-129 to facility personnel and the general public as a result of past, present, and future activities at DOE sites is of continuing interest, WINCO received about 160 samples annually in a variety of natural matrices, including snow, milk, thyroid tissue, and sagebrush, in which iodine-129 is determined in order to evaluate this dose, Currently, total iodine and the isotopic ratio of iodine-127 to iodine-129 are determined by mass spectrometry. These two measurements determine the concentration of iodine-129 in each sample, These measurements require at least 16 h of mass spectrometer operator time for each sample. A variety of methods are available which concentrate and determine small quantities of iodine. Although useful, these approaches would increase both time and cost. The objective of this effort was to determine total iodine by an alternative method in order to decrease the load on mass spectrometry by 25 to 50%. The preparation of each sample for mass spectrometric analysis involves a common step--collection of iodide on an ion exchange bed. This was the focal point of the effort since the results would be applicable to all samples.

  12. 21 CFR 520.1157 - Iodinated casein tablets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Iodinated casein tablets. 520.1157 Section 520.1157 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.1157 Iodinated casein tablets. (a) Specifications. Each 1-gram...

  13. Iodine-deficient vegetarians: a hypothetical perchlorate-susceptible population?

    PubMed

    Fields, Cheryl; Dourson, Michael; Borak, Jonathan

    2005-06-01

    Recent risk assessments of environmental perchlorate have been subject to much debate. A particular concern is whether appropriate susceptible sub-populations have been identified. Iodine-deficient pregnant women, especially vegetarians, have been proposed as such a potential susceptible sub-population, but there is no evidence of iodine deficiency in the US population and the adequacy of iodine nutrition has not been studied in US vegetarians. To understand the possibility that US vegetarians might be iodine deficient, we reviewed the prevalence, demography, and lifestyle characteristics of US vegetarians as well as the world literature on iodine nutrition in vegetarians. Our findings indicate that strict vegetarians and vegans, who comprise probably less than 0.1% of the US population, have higher education, higher incomes, and healthier lifestyles than the general population. Field studies indicate that vegetarian diets need not lead to iodine deficiency and vegans may suffer excess iodine intake. It is remains uncertain whether there are iodine-deficient vegans or pregnant women in the US. Of more general concern is whether the 10-fold default uncertainty factor is needed for intraspecies (i.e., within human) variability to protect such hypothetical susceptible sub-populations. PMID:15896441

  14. 21 CFR 520.1157 - Iodinated casein tablets.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iodinated casein tablets. 520.1157 Section 520... tablets. (a) Specifications. Each 1-gram tablet contains 25 milligrams of iodinated casein. (b) Sponsor. See No. 017762 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. 1/5 to 1 tablet...

  15. 21 CFR 520.1157 - Iodinated casein tablets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Iodinated casein tablets. 520.1157 Section 520... tablets. (a) Specifications. Each 1-gram tablet contains 25 milligrams of iodinated casein. (b) Sponsor. See No. 017762 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. 1/5 to 1 tablet...

  16. 21 CFR 520.1157 - Iodinated casein tablets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Iodinated casein tablets. 520.1157 Section 520... tablets. (a) Specifications. Each 1-gram tablet contains 25 milligrams of iodinated casein. (b) Sponsor. See No. 017762 in § 510.600(c) of this chapter. (c) Conditions of use—(1) Amount. 1/5 to 1 tablet...

  17. Comparison of methods for iodine analysis in foods.

    PubMed

    Judprasong, K; Jongjaithet, N; Chavasit, V

    2016-02-15

    Spectrophotometric and ICP-MS methodology for iodine determination was compared. Samples were alkali dry-ashed, dissolved in water, and iodine assayed by spectrophotometry and by ICP-MS. Iodine content in the studied foods ranged from 3 to 1304μg/100g. There was no significant difference (p>0.05) between iodine values determined spectrophotometrically using an external calibration curve and values determined using a standard addition. Foods containing low iodine concentrations (4-25μg/100g) also showed no significant difference (p>0.05) between iodine concentrations determined spectrophotometrically and concentrations determined by ICP-MS. For food items with more than 25μg/100g, the spectrophotometric methods yielded markedly higher (p<0.05) concentrations than the standard ICP-MS method (relative positive bias 25-122%), especially in foods with high sodium and/or iron contents. A catalytic effect of sodium and iron on the Sandell and Kolthoff reaction, leading to false high values in the spectrophotometric determination of iodine was demonstrated. ICP-MS is recommended for iodine determination in foods. PMID:26433281

  18. Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes

    PubMed Central

    Aakre, Inger; Strand, Tor A.; Bjøro, Trine; Norheim, Ingrid; Barikmo, Ingrid; Ares, Susana; Alcorta, Marta Duque; Henjum, Sigrun

    2016-01-01

    Iodine excess may impair thyroid function and trigger adverse health consequences for children. This study aims to describe iodine status among breastfed infants with high iodine exposure in the Saharawi refugee camps Algeria, and further assess thyroid function and iodine status among the children three years later. In 2010, a cross-sectional study among 111 breastfed children aged 0–6 months was performed (baseline study). In 2013, a second cross-sectional study (follow-up study) was conducted among 289 children; 213 newly selected and 76 children retrieved from baseline. Urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were measured at baseline. UIC, thyroid hormones and serum thyroglobulin (Tg) were measured at follow-up. At baseline and follow-up, 88% and 72% had excessive iodine intakes (UIC ≥ 300 µg/L), respectively. At follow-up, 24% had a thyroid hormone disturbance and/or elevated serum Tg, including 9% with subclinical hypothyroidism (SCH), 4% with elevated fT3 and 14% with elevated Tg. Children with SCH had poorer linear growth and were more likely to be underweight than the children without SCH. Excessive iodine intakes and thyroid disturbances were common among children below four years of age in our study. Further, SCH seemed to be associated with poor growth and weight. PMID:27367720

  19. Povidone iodine skin absorption: an ex-vivo study.

    PubMed

    Nesvadbova, Martina; Crosera, Matteo; Maina, Giovanni; Larese Filon, Francesca

    2015-06-15

    Povidone iodine is a water-soluble complex used to disinfect the skin surface and it exerts prolonged germicidal action against a broad spectrum of germs. Indeed, it is often applied on burned skin, large wounds, deep tissues or mucosa. Notably some surgical hand-scrub solutions, which are considered safe antiseptics, contain large amounts of iodine that can be absorbed by skin. The aim of present study was to study the skin absorption of iodine after the application on the skin of povidone-iodine solution, used by health care workers during surgical procedure. We use Franz diffusion static cells with human skin. After 24h from the beginning of our measurement the iodine concentration in the receiving compartment was 11.59±6.3μg/cm(2). The medium flux calculated was 0.73±0.33μg/cm(2)/h with a lag time of 8.9±1.5h. These in vitro results confirmed that povidone iodine could pass through the skin in a relevant amount that can explain the clinical findings in burned or surgically treated patients. In professional use the repetitive contact with povidone iodine, also as soap, can cause iodine skin permeation that must be considered when the washing procedures are repeated more than 20 times a day. PMID:25858112

  20. Neurocognitive outcomes of children secondary to mild iodine deficiency in pregnant women.

    PubMed

    Caron, Philippe

    2015-07-01

    Iodine deficiency is the most important preventable cause of brain damage worldwide. During pregnancy, severe iodine deficiency causes endemic cretinism, whereas mild-to-moderate iodine deficiency impairs neurocognitive function of the offspring. Numerous reports demonstrate the impact of iodine supplementation on prevention of cretinism, and recent studies evaluate the effects of iodine prophylaxis on neurocognitive development in children of women with mild-to-moderate iodine deficiency. Iodine prophylaxis is generally well tolerated without side effects for the pregnant women and the offspring. In France, the iodine status was recently considered as satisfactory in children and adult population, but regional studies conducted during the last two decades have shown that healthy women are mild-to-moderately iodine deficient during pregnancy. According to recent World Heath Organization guidelines, systematic iodine prophylaxis is recommended in women planning a pregnancy, during gestation and lactation in order to prevent maternal, neonatal and infantile consequences of mild-to-moderate iodine deficiency. PMID:25934357

  1. Iodine deficiency in pregnant women living in the South-East of the UK: the influence of diet and nutritional supplements on iodine status

    PubMed Central

    Bath, Sarah C.; Walter, Alan; Taylor, Andrew; Wright, John; Rayman, Margaret P.

    2015-01-01

    Iodine is a key component of the thyroid hormones which are crucial for brain development. Pregnant women are vulnerable to iodine deficiency because their requirement for iodine is higher than that of non-pregnant adults. Data on the iodine status of UK pregnant women are sparse and there are no such data in the South East. One hundred pregnant women were recruited to a cross-sectional study at the Royal Surrey County Hospital, Guildford, at their first-trimester visit for an ultrasound scan. Participants provided a spot-urine sample (for the measurement of urinary iodine and creatinine concentrations) and 24-hour excretion of iodine was estimated from the urinary iodine-to-creatinine ratio. Women completed a general questionnaire and a food-frequency questionnaire. The median urinary iodine concentration (85·3 μg/l) indicated that the group was iodine deficient by WHO criteria. The median values of the iodine-to-creatinine ratio (122·9 μg/g) and of the estimated 24-hr iodine excretion (151·2 μg/day) were also suggestive of iodine deficiency. Urinary iodine concentration was significantly higher in women taking an iodine-containing prenatal supplement (n=42) than in those not taking such a supplement (P<0·001). In adjusted analyses, milk intake, maternal age and iodine-containing prenatal supplement use were positively associated with estimated 24-hour urinary iodine excretion. Our finding of iodine deficiency in these women gives cause for concern. We suggest that women of childbearing age and pregnant women should be given advice on how to improve their iodine status through dietary means. A national survey of iodine status in UK pregnant women is required. PMID:24398008

  2. Appropriate iodine nutrition in Iran: 20 years of success.

    PubMed

    Delshad, Hossein; Mehran, Ladan; Azizi, Fereidoun

    2010-01-01

    Iodine is a trace element in the human body, its only known function is the synthesis of thyroid hormones. Effects of iodine deficiency, termed iodine deficiency disorders (IDD), include endemic goiter, hypothyroidism, cretinism, decreased fertility rate, increased infant mortality and mental retardation. 2.2 billion people worldwide are at risk for IDD. Of these, 30-70% have goiter and 1-10% have cretinism. Two decades ago the I.R. Iran was among the countries most severely affected by iodine deficiency, but during the last two decades has made much progress in the development of universal salt iodization strategies and IDD prevention, and since 1996 meets all WHO/UNICEF/ICCIDD criteria for the sustainable elimination of iodine deficiency. PMID:21287473

  3. Serial thyroid iodine content in hyperthyroid patients treated with radioiodine

    SciTech Connect

    Lee, G.S.; Sandler, M.P.; Patton, J.A.; Brill, A.B.

    1986-02-01

    X-ray fluorescent scanning was used to measure initial thyroidal iodine content in 64 patients diagnosed as being hyperthyroid and selected for I-131 therapy, and serially in 48 of these patients after therapy in an attempt to determine those patients that were at high risk of becoming hypothyroid. Iodine content fell rapidly after therapy, reaching a nadir at about three months. Based on the population studied, the chance of early hypothyroidism (within 12 months) is about 80% if the iodine content measured at three months is less than 2 mg. If the iodine content is greater than 2 mg, the chance is only about 14%. The serial measurement of thyroidal iodine content (with x-ray fluorescent scanning) may allow early identification of those patients at high risk of developing permanent hypothyroidism following a therapeutic dose of I-131.

  4. Advanced water iodinating system. [for potable water aboard manned spacecraft

    NASA Technical Reports Server (NTRS)

    Davenport, R. J.; Schubert, F. H.; Wynveen, R. A.

    1975-01-01

    Potable water stores aboard manned spacecraft must remain sterile. Suitable sterilization techniques are needed to prevent microbial growth. The development of an advanced water iodinating system for possible application to the shuttle orbiter and other advanced spacecraft, is considered. The AWIS provides a means of automatically dispensing iodine and controlling iodination levels in potable water stores. In a recirculation mode test, simulating application of the AWIS to a water management system of a long term six man capacity space mission, noniodinated feed water flowing at 32.2 cu cm min was iodinated to 5 + or - ppm concentrations after it was mixed with previously iodinated water recirculating through a potable water storage tank. Also, the AWIS was used to successfully demonstrate its capability to maintain potable water at a desired I2 concentration level while circulating through the water storage tank, but without the addition of noniodinated water.

  5. Coherent pulse propagation and self-induced transparency on degenerate transitions in atomic iodine

    NASA Astrophysics Data System (ADS)

    Xu, Gan; King, T. A.

    1984-07-01

    Coherent propagation of intense short laser pulses through degenerate absorbing media is investigated with the use of an atomic-iodine laser-absorber self-resonant combination. Four degenerate systems, the 2P12-2P32, F=3<-->F'=4, ΔMF=0,+/-1 and F=2<-->F'=2, ΔMF=0,+/-1 transitions, are studied under various conditions. Theoretical analysis based on the "pulse-area-pulse-energy" approach shows different pulse propagation behaviors for three typical types of degeneracy. Experimental results give good agreement with theoretical predictions. It is concluded that self-induced transparency exists in any degenerate two-level system, provided that suitable polarization of radiation is used. The usefulness of self-induced-transparency phenomena for measurements of transitional dipole moment and homogeneous relaxation time is also demonstrated.

  6. Precise measurements of hyperfine components in the spectrum of molecular iodine

    SciTech Connect

    Sansonetti, C.J.

    1996-05-01

    Absolute wave numbers with a typical uncertainty of 1 MHz (95% confidence) were measured for 102 hyperfine-structure components of {sup 127}I{sub 2}. The data cover the range 560-656 nm, with no gaps over 50 cm{sup -1}. The spectra were observed using Doppler-free frequency modulation spectroscopy with tunable cw laser. The laser was locked to selected iodine components and its wave number measured with a high precision Fabry-Perot wavemeter. Accuracy is confirmed by good agreement of 9 of the lines with previous results from other laboratories. These measurements provide a well-distributed set of precise reference lines for this spectral region.

  7. Incorporation of iodine in polymeric microparticles and emulsions

    NASA Astrophysics Data System (ADS)

    Kolontaeva, Olga A.; Khokhlova, Anastasia R.; Markina, Natalia E.; Markin, Alexey V.; Burmistrova, Natalia A.

    2016-04-01

    Application of different methods for formation of microcontainers containing iodine is proposed in this paper. Two types of microcontainers: microemulsions and microparticles have been investigated, conditions and methods for obtaining microcontainers were optimized. Microparticles were formed by layer-by-layer method with cores of calcium carbonate (CaCO3) as templates. Incorporation of complexes of iodine with polymers (chitosan, starch, polyvinyl alcohol) into core, shell and hollow capsules was investigated and loadings of microparticles with iodine were estimated. It was found that the complex of iodine with chitosan adsorbed at CaCO3 core is the most stable under physiological conditions and its value of loading can be 450 μg of I2 per 1 g of CaCO3. Moreover, chitosan was chosen as a ligand because of its biocompatibility and biodegradability as well as very low toxicity while its complex with iodine is very stable. A small amount of microparticles containing a iodine-chitosan complex can be used for prolonged release of iodine in the human body since iodine daily intake for adults is around 100 μg. "Oil-in-water" emulsions were prepared by ultrasonication of iodinated oils (sunflower and linseed) with sodium laurilsulfate (SLS) as surfactant solution. At optimal conditions, the homogenous emulsions remained stable for weeks, with total content of iodine in such emulsion being up to 1% (w/w). The oil:SLS ratio was equal to 1:10 (w/w), optimal duration and power of ultrasound exposure were 1.5 min and 7 W, correspondingly. Favorable application of iodized linseed oil for emulsion preparation with suitable oil microdroplets size was proved.

  8. Assessing infant cognitive development after prenatal iodine supplementation.

    PubMed

    Bell, Martha Ann; Ross, Alleyne P; Goodman, Gay

    2016-09-01

    Little information is available on infant behavioral development outcomes of prenatal iodine supplementation in regions of mild to moderate iodine deficiency. Studies performed to date, all of which relied on global developmental assessments, have yielded inconsistent findings with regard to psychomotor development, negative findings with regard to mental development, and no information as to the development of specific cognitive functions. Our review of these studies leads us to suspect that the use of global developmental assessments might partially explain the negative and inconsistent findings. To identify cognitive processes that might be sensitive to prenatal iodine supplementation, we examined the timing of thyroid hormone action on specific brain systems. The development of infant visual attention is sensitive to thyroid hormone during the early prenatal period, when the fetus is entirely dependent on maternal thyroid hormone. For this reason, infant visual attention has the potential to be a sensitive measure of infant outcomes in prenatal iodine supplementation studies. We suggest the assessment of infant visual attention, with follow-up examination of childhood executive functions, as a means of capturing the effects of maternal iodine deficiency and prenatal iodine supplementation on specific cognitive processes. In particular, we propose comparison of infant performance on global developmental tests and specialized tests of visual attention in pilot trials of prenatal iodine supplementation in regions of mild to moderate iodine deficiency. Only by comparing the 2 types of tests side by side will it be possible to establish whether the use of a sensitive measure of infant visual attention will increase the reliability of such supplementation studies. Recognizing that exposure misclassification may also provide a partial explanation for the inconsistent neurodevelopmental outcomes in previous studies, we suggest that urinary iodine concentration or

  9. Iodine intake in human nutrition: a systematic literature review

    PubMed Central

    Gunnarsdottir, Ingibjörg; Dahl, Lisbeth

    2012-01-01

    The present literature review is a part of the NNR5 project with the aim of reviewing and updating the scientific basis of the 4th edition of the Nordic Nutrition Recommendations (NNR) issued in 2004. The main objective of the review is to assess the influence of different intakes of iodine at different life stages (infants, children, adolescents, adults, elderly, and during pregnancy and lactation) in order to estimate the requirement for adequate growth, development, and maintenance of health. The literature search resulted in 1,504 abstracts. Out of those, 168 papers were identified as potentially relevant. Full paper selection resulted in 40 papers that were quality assessed (A, B, or C). The grade of evidence was classified as convincing, probable, suggestive, and no conclusion. We found suggestive evidence for improved maternal iodine status and thyroid function by iodine supplementation during pregnancy. Suggestive evidence was found for the relationship between improved thyroid function (used as an indicator of iodine status) during pregnancy and cognitive function in the offspring up to 18 months of age. Moderately to severely iodine-deficient children will probably benefit from iodine supplementation or improved iodine status in order to improve their cognitive function, while only one study showed improved cognitive function following iodine supplementation in children from a mildly iodine-deficient area (no conclusion). No conclusions can be drawn related to other outcomes included in our review. There are no new data supporting changes in dietary reference values for children or adults. The rationale for increasing the dietary reference values for pregnant and lactating women in the NNR5 needs to be discussed in a broader perspective, taking iodine status of pregnant women in the Nordic countries into account. PMID:23060737

  10. Revisiting History: Encountering Iodine Then and Now--A General Chemistry Laboratory to Observe Iodine from Seaweed

    ERIC Educational Resources Information Center

    Wahab, M. Farooq

    2009-01-01

    The history of the discovery of iodine is retold using brown-colored seaweed found commonly along the ocean shore. The seaweed is ashed at a low temperature and the iodides are extracted into boiling water. The iodides are oxidized in acidic medium. Solvent extraction of iodine by oxidation of iodides as well as simple aqueous extraction of iodide…

  11. Iodine waste form summary report (FY 2007).

    SciTech Connect

    Krumhansl, James Lee; Nenoff, Tina Maria; McMahon, Kevin A.; Gao, Huizhen; Rajan, Ashwath Natech

    2007-11-01

    This new program at Sandia is focused on Iodine waste form development for GNEP cycle needs. Our research has a general theme of 'Waste Forms by Design' in which we are focused on silver loaded zeolite waste forms and related metal loaded zeolites that can be validated for chosen GNEP cycle designs. With that theme, we are interested in materials flexibility for iodine feed stream and sequestration material (in a sense, the ability to develop a universal material independent on the waste stream composition). We also are designing the flexibility to work in a variety of repository or storage scenarios. This is possible by studying the structure/property relationship of existing waste forms and optimizing them to our current needs. Furthermore, by understanding the properties of the waste and the storage forms we may be able to predict their long-term behavior and stability. Finally, we are working collaboratively with the Waste Form Development Campaign to ensure materials durability and stability testing.

  12. Marine aerosol formation from biogenic iodine emissions.

    PubMed

    O'Dowd, Colin D; Jimenez, Jose L; Bahreini, Roya; Flagan, Richard C; Seinfeld, John H; Hämeri, Kaarle; Pirjola, Liisa; Kulmala, Markku; Jennings, S Gerard; Hoffmann, Thorsten

    2002-06-01

    The formation of marine aerosols and cloud condensation nuclei--from which marine clouds originate--depends ultimately on the availability of new, nanometre-scale particles in the marine boundary layer. Because marine aerosols and clouds scatter incoming radiation and contribute a cooling effect to the Earth's radiation budget, new particle production is important in climate regulation. It has been suggested that sulphuric acid derived from the oxidation of dimethyl sulphide is responsible for the production of marine aerosols and cloud condensation nuclei. It was accordingly proposed that algae producing dimethyl sulphide play a role in climate regulation, but this has been difficult to prove and, consequently, the processes controlling marine particle formation remains largely undetermined. Here, using smog chamber experiments under coastal atmospheric conditions, we demonstrate that new particles can form from condensable iodine-containing vapours, which are the photolysis products of biogenic iodocarbons emitted from marine algae. Moreover, we illustrate, using aerosol formation models, that concentrations of condensable iodine-containing vapours over the open ocean are sufficient to influence marine particle formation. We suggest therefore that marine iodocarbon emissions have a potentially significant effect on global radiative forcing. PMID:12050661

  13. Earth's Volatiles History and Cycles: the Case of Iodine

    NASA Astrophysics Data System (ADS)

    Bureau, H.; Marocchi, M.; Munsch, P.; Auzende, A.; Raepsaet, C.; Mezouar, M.; Testemale, D.; Kubsky, S.; Carriere, M.; Ricolleau, A.; Fiquet, G.

    2011-12-01

    Among the volatile elements present in our solar system, iodine is involved in mechanisms of primary importance during planet's evolution. The different isotopic signatures of 129Xe/132Xe for mantle and atmosphere between the Earth and Mars may reflect an early fractionation of xenon with respect to iodine. The role of fluids and more especially water is seriously envisaged to generate such a fractionation because whereas iodine is hydrophilic, xenon is not. Therefore iodine's early degassing with a water-rich fluid from a magma ocean is a good hypothesis to explain iodine, but also chlorine and bromine losses during early differentiation stages of the Earth. It was also shown that iodine is involved in natural ozone destruction in the Earth's atmosphere. Today we are able to detect iodine in volcanic emissions. The intensive subduction-zones volcanic degassing may explain the presence of iodine in the atmosphere if degassed together with water. The combination of synchrotron X-Ray characterization with diamond anvil cells, applied as magmatic and mantelic reactors to simulate pressure and temperature conditions of the planet interiors allows: (1) the characterization of fluids (aqueous, melt, supercritic) existing in the Earth; (2) element transfers via such fluids from depths to planets surfaces. Here, we have experimentally monitored iodine degassing from high pressure hydrous melts in situ in diamond anvil cells DAC by measuring iodine partitioning between aqueous fluids and hydrous melts during decompression. DAC experiments have been combined with high energy Synchrotron X-Ray Fluorescence at the beam lines Id27 and FAME from ESRF. Partition coefficients (D(I)fluid/melt = (I)fluid/(I)melt ) have been measured in situ from 500 to 900 °C and from 0.1 to 1.8 GPa. First results show that they are ranging from 1.9 (1.4 GPa) to 60 (0.1 GPa) and seem to tend to unity close to total miscibility between melts and aqueous fluids. At low pressure conditions (lower than

  14. Nutritional status of iodine in pregnant women in Catalonia (Spain): study on hygiene-dietetic habits and iodine in urine

    PubMed Central

    2011-01-01

    Background It is a priority to achieve an adequate nutritional status of iodine during pregnancy since iodine deficiency in this population may have repercussions on the mother during both gestation and post partum as well as on the foetus, the neonate and the child at different ages. According to the WHO, iodine deficiency is the most frequent cause of mental retardation and irrreversible cerebral lesions around the world. However, few studies have been published on the nutritional status of iodine in the pregnant population within the Primary Care setting, a health care level which plays an essential role in the education and control of pregnant women. Therefore, the aim of the present study is: 1.- To know the hygiene-dietetic habits related to the intake of foods rich in iodine and smoking during pregnancy. 2.- To determine the prevalence of iodine deficiency and the factors associated with its appearance during pregnancy. Methods/design We will perform a cluster randomised, controlled, multicentre trial. Randomisation unit: Primary Care Team. Study population: 898 pregnant women over the age of 17 years attending consultation to a midwife during the first trimester of pregnancy in the participating primary care centres. Outcome measures: consumption of iodine-rich foods and iodine deficiency. Points of assessment: each trimester of the gestation. Intervention: group education during the first trimester of gestation on healthy hygiene-dietetic habits and the importance of an adequate iodine nutritional status. Statistical analysis: descriptive analysis of all variables will be performed as well as multilevel logistic regression. All analyses will be done carried out on an intention to treat basis and will be fitted for potential confounding factors and variables of clinical importance. Discussion Evidence of generalised iodine deficiency during pregnancy could lead to the promotion of interventions of prevention such as how to improve and intensify health care

  15. 21 CFR 862.1640 - Protein-bound iodine test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of...

  16. 21 CFR 862.1640 - Protein-bound iodine test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of...

  17. 21 CFR 862.1640 - Protein-bound iodine test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of...

  18. 21 CFR 862.1640 - Protein-bound iodine test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of...

  19. 21 CFR 862.1640 - Protein-bound iodine test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Protein-bound iodine test system. 862.1640 Section... Systems § 862.1640 Protein-bound iodine test system. (a) Identification. A protein-bound iodine test system is a device intended to measure protein-bound iodine in serum. Measurements of...

  20. Iodine-mediated etching of gold nanorods for plasmonic sensing of dissolved oxygen and salt iodine.

    PubMed

    Zhang, Zhiyang; Chen, Zhaopeng; Cheng, Fangbin; Zhang, Yaowen; Chen, Lingxin

    2016-05-10

    Here, we have carefully investigated iodine-mediated etching of gold nanorods (AuNRs) in the presence of iodate and applied this phenomenon to on-site detection of dissolved oxygen (DO). Under given conditions, the quantitative conversion of target analytes DO to iodine leads to the etching of AuNRs along the longitudinal direction with the aid of cetyltrimethylammonium. As a result, the longitudinal localized surface plasmon resonance shifts to a short wavelength. The peak-shift can be used for quantitative determination of DO and iodate by a spectrophotometer. The satisfactory results from DO detection in different water samples and iodate detection in table salt indicate the feasibility of the proposed methods. Moreover, the as-prepared colorimetric test paper would make the detection more economical and simpler. PMID:27049138