WorldWideScience
1

Ionizing radiation hardening procedure of CCD's  

International Nuclear Information System (INIS)

The procedure of charge-coupled devices (CCD) are investigated by using MOS capacitors for enhancing their ionizing radiation tolerance. Authors have found that the gate oxidation temperature, thickness of SiO_2 gate insulator and high temperature processes after gate oxidation are crucial for determining the radiation tolerance of the devices, and proposed to decrease the thickness of gate insulator, perform gate oxidation at 1000 deg C by means of dry oxidation and minimize the number of high temperature procedure steps after gate oxidation. All stated above is a necessary preparation for priducing radiation hardened charge-coupled devices.

2

Study of total ionizing dose radiation effects on nitride/oxide stack gate MOS capacitor  

International Nuclear Information System (INIS)

The aim of this paper is to investigate the total ionizing dose (TID) radiation effects on MOS capacitor with nitride/oxide stack gate. The stack gate MOS capacitors are fabricated with 20 nm oxide, 40 nm nitride or 110 nm nitride respectively. Through the analysis of CV curve of the irradiation capacitors, it is found that the degradation of the CV curve is due to a significant increase of interface traps and somewhat smaller oxide charge. It is also shown that the thicker of the nitride, more interface traps and oxide charge will be occurred. (authors)

2008-07-01

3

Tritium monitor with improved gamma-ray discrimination  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and method for selective measurement of tritium oxide in an environment which may include other radioactive components and gamma radiation, the measurement including the selective separation of tritium oxide from a sample gas through a membrane into a counting gas, the generation of electrical pulses individually representative by rise times of tritium oxide and other radioactivity in the counting gas, separation of the pulses by rise times, and counting of those pulses representative of tritium oxide. The invention further includes the separate measurement of any tritium in the sample gas by oxidizing the tritium to tritium oxide and carrying out a second separation and analysis procedure as described above.

1985-01-01

4

Basic mechanisms of radiation effects in the natural space radiation environment  

Energy Technology Data Exchange (ETDEWEB)

Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

1994-06-01

5

AQ4N: an alkylaminoanthraquinone N-oxide showing bioreductive potential and positive interaction with radiation in vivo.  

UK PubMed Central (United Kingdom)

AQ4N (1,4-bis([2-(dimethylamino-N-oxide)ethyl]amino)5,8-dihydroxy- anthracene-9,10-dione) is a novel alkylaminoanthraquinone N-oxide which, on reduction, forms a stable DNA affinic cytotoxic compound...Full Text Available

1995-07-01

6

Radiation oxidation of phenol in petrochemical waste water. II  

International Nuclear Information System (INIS)

The rate was studied of radiation destruction of phenol aqueous solutions at a concentration range of 1 to 100 ppm. Irradiated were model solutions containing additions of some organic and inorganic substances typical of the petrochemical industry. In view of the fact that the radiation destruction kinetics is determined by the amount of dissolved oxygen in the sample and by the phenol concentration, relatively low doses were used. Thus, a sufficient amount of oxygen in the sample and therefore the oxidation mechanism of radiolysis were ensured. The dose-response relationships for phenol destruction were studied using doses of 50, 100, 200 and 400 J.kg"-"1; the limit dose was 500 J.kg"-"1. From the results obtained, a kinetic model was constructed of radiation phenol oxidation in aqueous solutions in the presence of various organic and inorganic additions. (B.S.).

1981-01-01

7

Formation of metal oxides by cathodic arc deposition  

Energy Technology Data Exchange (ETDEWEB)

Cathodic arc deposition is an established and industrially applied technique for the formation of nitrides (e.g. TiN); it can also be used for metal oxide thin film formation. A cathodic arc plasma source with the desired cathode material is operated in an oxygen atmosphere of appropriate pressure, and metal oxides of various stoichiometric composition can be formed on different substrates. We report here on a series of experiments on metal oxide formation by cathodic arc deposition for different applications. Black copper oxide has been deposited on accelerator components to increase the radiative heat transfer between the parts. Various metal oxides such as tungsten oxide, niobium oxide, nickel oxide and vanadium oxide have been deposited on ITO glass to form electrochromic ...

1995-11-01

8

Identification of oxidation states of ultra-trace elements by radiation detection  

International Nuclear Information System (INIS)

The determination of the oxidation state of ultra-trace elements in the environment, especially in the case of actinides, is of importance in many ways. Speciation techniques using radiation may comprise methods based on the detection of the nuclear and atomic radiations emitted in radioactive decay or methods using external sources of excitation. In the former instance, information can be obtained from the energy and intensity of radiation, but at present the partition method is still the most commonly used, although its reliability is questionable. Excitation with intense laser beams, as is currently being used for trace element analysis in photoacoustic and thermal lensing spectroscopic techniques, could conceivably be applied under suitable conditions to ultra-trace elements with a sensitivity approaching that of the radiochemical methods.

1989-11-01

9

Radiation hardening of smart electronics  

International Nuclear Information System (INIS)

Microprocessor based ''smart'' pressure, level, and flow transmitters were tested to determine the radiation hardness of this class of electronic instrumentation for use in reactor building applications. Commercial grade Complementary Metal Oxide Semiconductor (CMOS) integrated circuits used in these transmitters were found to fail at total gamma dose levels between 2500 and 10,000 rad. This results in an unacceptably short lifetime in many reactor building radiation environments. Radiation hardened integrated circuits can, in general, provide satisfactory service life for normal reactor operations when not restricted to the extremely low power budget imposed by standard 4--20 mA two-wire instrument loops. The design of these circuits will require attention to vendor radiation hardness specifications, dose rates, process control with respect to radiation ...

10

Radioprotective Effect of American Ginseng on Human Lymphocytes at 90 Minutes Postirradiation: A Study of 40 Cases  

UK PubMed Central (United Kingdom)

AbstractBackgroundIonizing radiation (IR) initiates intracellular oxidative stress through enhanced formation of reactive oxygen species (ROS) that attack DNA leading...Full Text Available

2010-05-01

11

Total dose hardening of SIMOX buried oxides for fully depleted devices in rad-tolerant applications  

International Nuclear Information System (INIS)

A total dose hardening treatment is applied to SIMOX buried oxides. Total ionizing dose radiation testing is performed on fully-depleted transistors fabricated on both hardened and non-hardened substrates. At 200 krads x-ray dose, the front gate shift is reduced from -0.7 to -0.2 V for FETs built on the hardened wafers.

1996-07-15

12

Improvements in or relating to refractory oxide protective coatings for fuel can  

International Nuclear Information System (INIS)

An improved coating for Advanced Gas Cooled Nuclear Reactor austenitic stainless steel fuel cans is described which, tests have shown, inhibits the deposition of carbon on the cans in carbon-containing ionising radiation environments. The coating comprises a refractory oxide which has been prepared by a vapour phase condensation method, in combination with a noble metal. (U.K.).

13

Radiation treatment of some poultry products  

International Nuclear Information System (INIS)

Practical procedures were developed for large-scale microbial decontamination of dry egg powder and gelatine with gamma radiation ("6"0Co). The formation and lifes of free organic radicals in these materials were examined by ESR measurements of powder samples. The concentration of these radicals was studied in dependence on the time of storage. Secondary oxidation of egg fats by air oxygen was investigated. Sensoric tests of irradiated gelatine, both in powder and hydrogel form, were performed. (author). 4 figs., 2 tabs., 2 refs.

1988-09-26

14

Effect of rapid thermal annealing on radiation hardening of MOS devices  

International Nuclear Information System (INIS)

The influence of RTA (Rapid Thermal Anneal) treatment on MOS radiation hardness is demonstrated and compared with classical furnace treatment. In the case of the RTA, the oxide trapped charge is found to depend on: (i) the anneal temperature as expected, data are in good agreement with a recently developed model of oxygen out-diffusion; (ii) the location across the wafer with a radial dependence, results could be related to stress induced by thermal gradient.

1995-07-17

15

A small particle selective emitter for thermophotovoltaic energy conversion  

Energy Technology Data Exchange (ETDEWEB)

This paper presents an analysis of the performance of a selective emitter using small particles of rare earth compounds stable at high temperatures in a low emittance inert gas stream. An expression for the spectral emissive power excluding radiation scattering was derived to include the radiation in the emission band, produced by electronic transitions of the rare earth ion, and the continuum radiation outside the emission band produced by the rare earth host. Preliminary results suggest that a selective emitter based on suspended rare earth oxide particles will have high efficiency and merits further experimental investigation. {copyright} {ital 1996 American Institute of Physics.}

1996-02-01

16

Radiation-induced damage to DNA; Les lesions radio-induites de l'ADN  

Energy Technology Data Exchange (ETDEWEB)

This short survey focuses on the main radiation-induced base lesions that have been identified within cellular DNA. For this purpose, sensitive assays that are aimed at measuring a few modifications per 10{sup 7} normal bases were set-up. In that respect high performance liquid chromatography - tandem mass spectrometry (CLHP-MS/MS) was found to be able to single out the formation of 9 oxidized nucleosides and two modified nucleo-bases out of the 70 oxidative base lesions that have been identified in model systems. As a striking result, it was found that in the DNA of {gamma}-irradiated human monocytes, the formamide-pyrimidine derivative of guanine is produced in a higher yield than the ubiquitous 8-oxo-7,8-dihydro-guanine damage, both arising from the same radical precursor. However, relatively high doses of ionizing radiation (> 20 Gy) have to be applied in order to detect an increase in the ...

2002-03-01

17

The effects of cosmic radiation on implantable medical devices  

Energy Technology Data Exchange (ETDEWEB)

Metal oxide semiconductor (MOS) integrated circuits, with the benefits of low power consumption, represent the state of the art technology for implantable medical devices. Three significant sources of radiation are classified as having the ability to damage or alter the behavior of implantable electronics; Secondary neutron cosmic radiation, alpha particle radiation from the device packaging and therapeutic doses(up to 70 G{gamma}) of high energy radiation used in radiation oncology. The effects of alpha particle radiation from the packaging may be eliminated by the use of polyimide or silicone rubber die coatings. The relatively low incidence of therapeutic radiation incident on an implantable device and the use of die coating leaves cosmic radiation induced secondary neutron single event upset ...

1996-12-31

18

Radiation thermocatalytic processes of hydrogen production from water  

International Nuclear Information System (INIS)

The results of studies of radiation-thermocatalytic water decomposition in the 673-773 K temperature range in the presence of BeO and titanium Y-type zeolite are presented. It is found that radiation-thermocatalytic processes of hydrogen production from water are characterized by a lower activation energy (55.4 kJ/mole) as compared with thermocatalytic processes (88.4 kJ/mole). The radiation-thermocatalytic process rate in the presence of oxide systems is not an additive sum of rates of radiation-catalytic (at 296-300 K) and thermocatalytic processes of water decomposition. On the basis of obtained results the conclusion is made that during radiation-catalytic decomposition of water in a heterogeneous system BeO + H_2O the main contribution into this process is made by excitons, radiation-chemical yields of excitons and non-equilibrium ...

19

Radiation hardening of CMOS-based circuitry in SMART transmitters  

International Nuclear Information System (INIS)

Process control transmitters that incorporate digital signal processing could be used advantageously in nuclear power plants; however, because such transmitters are too sensitive to radiation, they are not used. The Electric Power Research Institute sponsored work at Sandia National Laboratories under EPRI contract RP2614-58 to determine why SMART transmitters fail when exposed to radiation and to design and demonstrate SMART transmitter circuits that could tolerate radiation. The term ''SMART'' denotes transmitters that contain digital logic. Tests showed that transmitter failure was caused by failure of the complementary metal oxide semiconductors (CMOS)-integrated circuits which are used extensively in commercial transmitters. Radiation-hardened replacements were not available for the radiation-sensitive CMOS circuits. A conceptual design showed that a ...

20

Ion-radiation hardening of magnesium oxide crystals  

International Nuclear Information System (INIS)

Consideration is given to the data, demonstrating the effect of ion radiation on strength characteristics of ionic crystals, presented by magnesium oxide. Crystals, prepared in the form of plates, were irradiated by Si"+, Fe"+, C"+ ions by the dose of 10"1"6-10"1"7 ion/cm"2 at room temperature in vacuum. The following characteristics were investigated: dislocation density, microhardness, crack resistance. Investigation of dislocation structure showed, that dislocation density in irradiated sample was 2-3 times higher, as compared to nonirradiated one. Sufficient increase of fracture viscosity of MgO crystals was revealed. It can be conditioned by occurrence of compression stresses in the surface layer, decelerating crack formation and propagation.

21

The Protective Effect of Antioxidants on Oxidative Stress in Rats Exposed to the 950 MHz Electromagnetic Field  

International Nuclear Information System (INIS)

Studies have linked cell phone radiation to health problems such as headaches, high blood pressure, cancer and more. There is a latency period for most diseases and it may take years and more studies before the required weight of evidence is established. But the effects are cumulative and precautions should be taken now before it is too late. The aim of the present study was to investigate if supplementation with antioxidants would protect heart and liver tissues from harmful radiation emitted by cell phone. Thirty two male albino rats were randomly divided into four equal groups: I- Control, II- Antioxidants treated group, III- 950 MHz EMR, IV- 950 MHz EMR + antioxidants. A 950 MHz EMR radiation (217-Hz pulse rate, 2-W maximum peak power, SAR Specific Absorption Rate"1.6 W/Kg) was applied to groups III and IV 60 min/day, for 30 days using an experimental exposure device. Antioxidants supplement (Vitamins A, E and C + Se) ...

22

Assessment of the role of oxygen and mitochondria in heat shock induction of radiation and thermal resistance in Saccharomyces cerevisiae  

Energy Technology Data Exchange (ETDEWEB)

In response to a heat shock, the yeast Saccharomyces cerevisiae undergoes a large increase in its resistance to heat and, by the induction of its recombinational DNA repair capacity, a corresponding increase in resistance to radiation. Yeast which lack mitochondrial DNA, mitochondria-controlled protein synthetic apparatus, aerobic respiration, and electron transport (rho/sup 0/ strain) were used to assess the role of O/sub 2/, mitochondria, and oxidative processes controlled by mitochondria in the induction of these resistances. We have found that rho/sup 0/ yeast grown and heat shocked in either the presence or absence of O/sub 2/ are capable of developing both radiation and heat resistance. We conclude that neither the stress signal nor its cellular consequences of induced heat and radiation resistance are directly dependent on O/sub 2/, mitochondrial DNA, or mitochondria-controlled protein synthetic ...

1983-10-01

23

Model and simulation of heat transfer, magnetite oxidation and NOx formation in a grate-kiln taconite pellet induration furnace  

Energy Technology Data Exchange (ETDEWEB)

A numerical model was developed to simulate the combined effects of heat transfer, magnetite oxidation, and NO{sub x} formation in a grate-kiln furnace for taconite pellet induration. Heat transfer from the flame in the kiln was described by the net radiation method. The shrinking core model was used to account for magnetite oxidation on the grate. A novel approach to oxidation of tumbling pellets in a kiln was derived. The Zeldovich mechanism was used to predict thermal NO generation. Temperature fluctuations in the gas streams were estimated with a clipped Gaussian probability density function. The thermal energy balances and mass balances resulted in coupled systems of first-order differential equations, which were solved numerically. The model is capable of predicting NO production and magnetite oxidation in agreement with observation of plant performance. Although the design of ...

1996-12-31

24

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

25

Complex radiation degradation behavior of PVC materials under accelerated aging conditions  

Energy Technology Data Exchange (ETDEWEB)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the leveling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests.

1983-07-01

26

Radiation resistance of nylon. [Gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Various nylons including nylon 6, nylon 66, nylon 610 and nylon 12 in the forms of fiber and film were irradiated with the gamma-ray from Co-60 at the dose rate of 0.12 Mrad/hr in the atmosphere of oxygen at 7 kg/cm/sup 2/ and at the room temperature. The irradiation in vacuum on the same specimens was performed at 0.5 Mrad/hr. The tensile properties and the gel fraction of the irradiated nylon samples were measured, and the radiation resistance of the nylons against the irradiation at low dose rate was estimated. From the experimental results, it became clear that in the case of irradiation in vacuum, all the nylons were durable to the irradiation of 250 Mrad or more, and nylon 6 was more durable than nylon 12, and in the case of irradiation in pressurized oxygen, the radiation resistance of the nylons decreased to one-tenth as compared with that in vacuum, and contrary to that in vacuum, nylon 12 was superior to nylon 6, while nylon 610 was ...

1983-12-01

27

THE RADIATION INDUCED OXIDATION AND REDUCTION REACTIONS OF IRON IN AQUEOUS SOLUTIONS. VII. THE DIRECT OBSERVATION OF REDOX PROCESSES IN THE IRRADIATED Fe-H$sub 2$SO$sub 4$-CARBOXYLIC ACIDS- H$sub 2$ -O$sub 2$ SYSTEM. THE EFFECTS OF THE STRUCTURE OF ACIDS  

Science.gov (United States)

The effects of the structure of a carboxylic acid on the processes of oxidation and reduction of iron ions in irradiated aqueous solutions were directly observed during irradiation. The solutions contained the mono- or dicarboxylic acid, H/sub 2/SO/sub 4/, Fe(NH/sub 4/)/sub 2/(SO/sub 4/)/sub 2/ and O/sub 2/. Th e ferrous oxidation was rather independent of the acid and its concentration, but the reduction of ferric was possible in the presence of formic, oxalic, or valeric acid only. The radical formed from the valeric acid acts similar to those formed from hydrocarbons. The G-values of oxidation and reduction of the iron ions were established. The molar extinction coefficients for oxalic and malonic complexes of ferric ions were determined. (auth)

1963-01-01

28

Third World Congress on Oxidation Catalysis  

CERN Document Server

Third World Congress on Oxidation Catalysis

1997-01-01

29

Ultraviolet upconversion luminescence enhancement in Yb3+/Er3+-codoped Y2O3 nanocrystals induced by tridoping with Li+ ions  

International Nuclear Information System (INIS)

Ultraviolet (UV) upconversion (UC) luminescence in Yb3+/Er3+-codoped yttrium oxide (Y2O3) nanocrystals can be enhanced by orders of magnitude via tridoping further with Li+ ions under diode laser excitation of 970 nm. Sensitized three-photon UC radiations at 390 and 409 nm, corresponding to the 4G11/2?4I15/2 and 4H9/2?4I15/2 of Er3+ ions, respectively, present an enhancement time of about 33 times, which is larger than the 24 times enhancement for the UC green radiation. The UV UC radiation at 320 nm that corresponds to the 2P3/2?4I15/2 of Er3+ ions has also been greatly enhanced. Theoretical calculations interpret that all the observed enhancement times of UV UC radiations arise from the prolonged lifetimes of their intermediate states.

2009-03-01

30

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging. 2  

International Nuclear Information System (INIS)

Radiation-and-thermal-combined degradation of some kinds of cable insulating and jacketing materials was evaluated by accelerated aging tests. Plasticized polyvinyl chloride (PVC), silicone rubber, crosslinked and non-crosslinked halogen-free flame-retardant polyolefins (NH-XLPO and NH-PO) and ethylene-propylene rubber (EP rubber) of experimental formulation were degraded at accelerated rates, that are 50-1000 times the degradation rate under standard conditions (e.g.; 1Gy/h, 50degC), and a method to assess the lifetime of these materials under standard conditions was studied. The degradation was investigated by measuring tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for these materials were in proportion to the increase in accelerated rate. The PVC lifetime estimated from sequential aging tests had a tendency to extend beyond that from simultaneous aging tests, while the lifetime of other materials estimated ...

1994-01-01

31

Gamma and X-ray shielding compositions utilizing bauxite - Red Mud regional research laboratory (CSIR), Bhopal, India  

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: The application spectrum of X-ray and Gamma radiation is increasing exponentially in the area of diagnostic, nuclear medicine, food preservation, nuclear power plants and strategic utilities. To prevent the harmful effects of these radiations, shielding materials based on lead metal and its compounds are being used historically, which are toxic in nature. To protect environment it has become necessary to develop non-toxic lead free shielding materials. The use of titanium metal and its compounds as synthetic rock i.e. SYNROC are reported to be very effective non-toxic shielding materials for various applications. Red mud waste generated in aluminum producing industries possesses a unique mineralogical compositions containing fairly high quantity of titanium oxide and iron oxide useful for making non toxic shielding compositions and ...

2007-09-02

32

Fluxes of methane and nitrogen oxides in various boreal mire ecosystems. Effects of land-use activities and environmental changes  

Energy Technology Data Exchange (ETDEWEB)

Atmospheric impact of peatlands is a sum of their gas fluxes. In contrast to carbon dioxide, peatlands are net sources for methane (CH{sub 4}). Methane is an end product in the anaerobic decomposition processes and it has greater capacity to absorb infrared radiation than carbon dioxide. Most of the data on the CH{sub 4} release from northern peatlands is from North America. The total amount of methane released from wetlands is calculated to be 110 Tg yr{sup -1} of which 34 percent (38 Tg yr{sup -1}) is estimated to be emitted from the northern peatlands. Peat with high content of nitrogen is a potential source for gaseous nitrogen oxides, i.e. nitrous oxide (N{sub 2}O) and nitric oxide (NO). However, the importance of peatlands in producing these trace gases is poorly known. Nitrous oxide and nitric oxide are important components in the atmospheric chemistry ...

1996-12-31

33

Comparative studies on titanium and tantalum oxides thin film structures for laser mirrors, deposited by ion assisted gun  

International Nuclear Information System (INIS)

For obtaining radiation less damagable laser mirrors, a preliminary optimization of film fabrication suitable for the analysis of laser damage mechanism has been done as the first step. Here, the optimization requires not only the stable fabrication process but also the ideal film structure i.e., the amorphous and smooth film structure simultaneously, eliminating latently unwanted secondary effects such as light scattering during laser damage test. For this purpose, we adopted the ion assisted deposition (IAD) method and modified the deposition conditions for titanium and tantalum oxide films, both of which compose typical high index layers, and where SiO_2 layers are also chosen as low index layers because of their amorphous and smooth nature, in alternative multilayer laser mirrors. Surface and cross sectional film structures and film crystallinity are compared and characterized, using a high resolution SEM and a x-ray diffractometer, ...

1996-10-07

34

Study of degradation diagnosis for low voltage cable aged by thermal and radiation with time domain dielectric spectrometer  

International Nuclear Information System (INIS)

Non-destructive methods of diagnosis for detecting cable degradation by aging are being studied recently for improvement of electric wires and cables. This study examines degradation behaviors of cable sheath and insulation by combined accelerated aging tests applying thermal and radiation stresses simultaneously using a typical low voltage cable. According to experiments, elongation of cross-linked polyethylene insulation deteriorated at a faster rate than PVC sheath did under low doses below 50 Gy/h. Therefore, measurements using a time domain dielectric spectrometer (TDS) were carried out for the purpose of developing a method of degradation diagnosis of insulation. It was found that values of tan#delta# measured at very low frequencies below 0.1 Hz increase in pace with degradation of insulation reflecting the level of degradation more effectively than those measured at frequencies around the commercial frequency. In order to consider causes of the increases of ...

2000-05-01

35

Neutron resonances in /sup 100/Mo and valence neutron capture  

Science.gov (United States)

Neutron resonance interactions with /sup 100/Mo were studied at a time-of-flight facility. The transmission of two oxide samples (97.4% /sup 100/Mo) was measured at a 78.20 m flight path and the neutron capture cross section was measured at 40.12 m. Resonance analyses yielded parameters of 124 resonances. Capture ..gamma..-ray spectra from 11 resolved resonances were measured with a Ge(Li) detector at a 10.45 m flight path. In contrast to neighboring nuclei, partial radiation widths of strong p-wave resonances are not in agreement with valence model predictions.

1979-07-01

36

Environmental pollutant isotope measurements and natural radioactivity assessment for North Tushki area, south western desert, Egypt  

Energy Technology Data Exchange (ETDEWEB)

Natural radioactive materials under certain conditions can reach hazardous radiological levels. The natural radionuclide ({sup 238}U, {sup 232}Th, {sup 40}K) contents of rock samples at various locations in the North Tushki area were investigated using gamma-spectrometric analysis. Estimates of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The equivalent radium (R{sub eq}) and the external hazard index (H{sub ex}) which resulted from the natural radionuclides in soil are also calculated and tabulated. The studied samples have been collected from various rock exposures in the North Tushki area. The distribution of major oxides, U and Th were studied. It is found that the enrichment and depletion of the major oxides are mainly due to the effect of hydrothermal alteration, which caused mobility of some major oxides, which increases some elements and ...

2002-09-01

37

Punica granatum peel extract protects against ionizing radiation-induced enteritis and leukocyte apoptosis in rats  

International Nuclear Information System (INIS)

Radiation-induced enteritis is a well-recognized sequel of therapeutic irradiation. Therefore we examined the radioprotective properties of Punica granatum peel extract (PPE) on the oxidative damage in the ileum. Rats were exposed to a single whole-body X-ray irradiation of 800 cGy. Irradiated rats were pretreated orally with saline or PPE (50 mg/kg/day) for 10 days before irradiation and the following 10 days, while control rats received saline or PPE but no irradiation. Then plasma and ileum samples were obtained. Irradiation caused a decrease in glutathione and total antioxidant capacity, which was accompanied by increases in malondialdehyde levels, myeloperoxidase activity, collagen content of the tissue with a concomitant increase 8-hydroxy-2'-deoxyguanosine (an index of oxidative DNA damage). Similarly, pro-inflammatory cytokines (TNF-?, IL-1? and IL-6) and lactate dehydrogenase were elevated in irradiated groups as ...

2009-07-01

38

Metabolic effects of microwave radiation and convection heating on human mononuclear leukocytes. Final report, January 1985-May 1986  

Energy Technology Data Exchange (ETDEWEB)

Investigated here were the effects of microwave (MW) radiation (2450-MHz, continuous-wave, mean specific absorption rate of 103.5 + or - 4.2 W/kg) and convention heating on the nonphosphorylating oxidative metabolism of human peripheral mononuclear leukocytes (96% lymphocytes, 4% monocytes) at 37 C. Metabolic activity, determined by chemiluminescence (CL) of cells challenged with luminol (5-aminO-2, 3-dihydro-1, 4-phthalazinedione) linked to bovine serum albumin, was detected with a brightness photomer. A significant stimulation after after MW exposure (p < 0.005) over total CL of matched 37 C-incubator controls was observed. A similar degree of stimulation, compared to incubator controls, was also detected after sham treatment. No significant difference existed between changes in total CL or stimulation indices of the MW and sham-exposed groups. Exposure to MW radiation, under normothermic (37 + or - 0.03 C) conditions, ...

1986-01-01

39

Radiolytic stabilization of poly(methyl methacrylate) using commercial additives; Estabilizacao radiolitica do poli(metacrilato de metila) usando aditivos comerciais  

Energy Technology Data Exchange (ETDEWEB)

Poly(methyl methacrylate), PMMA, Acrigel, a Brazilian polymer, is used in the manufacture of medical supplies sterelizable by ionizing radiation. However, when PMMA is gamma-irradiated it undergoes main chain scissions, which promote molecular degradation causing reduction in its mechanical properties. Therefore, radiolytic of PMMA is important for it to become commercially radiosterizable. In this work some commercial additives, originally used in photo-and thermo-oxidate stabilization of polymers, were tested. Only two additives, type HALS (Hindered Amine Light Stabilizer), denoted Scavenger, showed a good protective quality. The investigation of radiation-induced main scissions was carried out by viscosimetric method. The most effective additive, added to the polymer system at 0.3 w/w%, promotes a great molecular radioprotection of 93%. That means a reduction of G-value (scissions/100 eV) from 0.611 to 0.053. In ...

2000-04-01

40

Effects of gamma and electron beam irradiation on the properties of calendered cord fabrics  

Energy Technology Data Exchange (ETDEWEB)

The effects of gamma and e-beam irradiation on mechanical and structural properties of nylon 66 (Ny 66), nylon 6 (Ny 6) and poly(ethylene terephthalate) (PET) fabrics used in tyres were investigated. The untreated (greige), treated cords and calendered fabrics were irradiated at different doses. It is found that the effects of high energy irradiation on greige, treated cords and calendered fabrics are similar. No protective effect of compounds used in calendering was observed against radiation-induced oxidative degradation. The deterioration effect of gamma irradiation on mechanical properties is much higher than that of e-beam irradiation for all types of samples. Limiting viscosity numbers of both gamma and e-beam irradiated nylon 6 and nylon 66 cords were found to decrease with increasing dose. It is concluded that PET calendered fabric has higher resistance to ionizing radiation. Ny 6 and Ny 66 calendered fabrics are ...

2010-03-15

41

Sorbent for use in hot gas desulfurization  

Energy Technology Data Exchange (ETDEWEB)

A multiple metal oxide sorbent supported on a zeolite of substantially silicon oxide is used for the desulfurization of process gas streams, such as from a coal gasifier, at temperatures in the range of about 1200.degree. to about 1600.degree. F. The sorbent is provided by a mixture of copper oxide and manganese oxide and preferably such a mixture with molybdenum oxide. The manganese oxide and the molybdenum are believed to function as promoters for the reaction of hydrogen sulfide with copper oxide. Also, the manganese oxide inhibits the volatilization of the molybdenum oxide at the higher temperatures.

1993-01-01

42
44

Some comments on BEIR III  

International Nuclear Information System (INIS)

... organizations irradiation radiation doses radiation effects RADIATIONS.

1982-01-01

45

Radiation technology of wood-plastic composite materials  

International Nuclear Information System (INIS)

... radiation effects RADIATIONS. WOOD-PLASTIC COMPOSITES.

1981-10-02

46
47

Global changes and the air-sea exchange of chemicals  

International Nuclear Information System (INIS)

Present and potential future changes to the global environment have important implications for marine pollution and for the air-sea exchange of both anthropogenic and natural substances. This report addresses three issues related to the potential impact of global change on the air-sea exchange of chemicals: Global change and the air-sea transfer of the nutrients nitrogen and iron. Global change and the air-sea exchange of gases. Oceanic responses to radiative and oxidative changes in the atmosphere. The deposition of atmospheric anthropogenic nitrogen has probably increased biological productivity in coastal regions along many continental margins. Atmospheric deposition of new nitrogen may also have increased productivity somewhat in mid-ocean regions. The projected future increases of nitrogen oxide emissions from Asia, Africa and South America will provide significant increases in the rate of deposition of ...

1996-08-01

48

Food packaging and radiation sterilization  

International Nuclear Information System (INIS)

Radiation sterilization has several merits that it is a positively effective sterilization method, it can be used to sterilize low heat-resistant containers and high gas barrier films, and there is no possibility of residual chemicals being left in the packages. It has been commercially used in 'Bag in a Box' and some food containers. The #gamma# ray and an electron beam are commonly used in radiation sterilization. The #gamma# ray can sterilize large size containers and containers with complex shapes or sealed containers due to its strong transmission capability. However, since the equipment tends to be large and expensive, it is generally used in off production lines. On the other hand, it is possible to install and electron beam system on food production lines since the food can be processed in a short time due to its high beam coefficient and its ease of maintenance, even though an electron beam has limited usage such as sterilizing ...

1998-12-08

49

Correlation between mechanical stress and hydrogen-related effects on radiation-induced damage in MOS structures  

Energy Technology Data Exchange (ETDEWEB)

Correlation between mechanical stress and hydrogen effects on radiation damage in polycide-gate MOS capacitors was investigated as a function of gate-oxide thickness. The compressive stress magnitude was altered by varying the silicide (TiSi/sub 2/ or WSi/sub 2/) thickness in the polycide-gate electrode, and hydrogen introduction into gate-SiO/sub 2/ film was carried out by diffusion from plasma-deposited silicon-nitride passivation film (SiN-Cap). In a MOS capacitor without passivation film (No-Cap sample), it was found that compressive stress on gate-SiO/sub 2/ reduces both positive charge build-up (..delta..Qot) and interface-trap generation (..delta..Dit). Radiation induced shift, ..delta..Qot exhibits a smaller stress effect as compared with ..delta..Dit. As gate-SiO/sub 2/ thickness decreases, the stress effect on ..delta..Qot increases, while this effect on ..delta..Dit remains nearly constant. This compressive ...

1987-12-01

50

X-ray and UV-light irradiation effects on oxide superconducting thin films  

International Nuclear Information System (INIS)

Oxide superconducting thin films were irradiated with X-rays and ultra-violet (UV) light, and induced radiation effects on electrical and chemical properties were examined by transport measurement, X-ray diffraction analysis (XRD), diamagnetization measurement and X-ray photoemission spectroscopy (XPS). After irradiation for ErBa_2Cu_3O_x films with X-rays emitted from a Rh tube for 100 hours, superconductivity was remarkably damaged, destroying the zero-resistance state. The UV-light irradiation for Bi_2Sr_2CaCu_2O_x films was performed in He gas of about 500 Pa with a low pressure mercury lamp. The superconductivity was gradually degraded with the UV irradiation time up to 70 minutes. In both cases, adequate oxygen-annealing treatments restored superconductivity. The X-ray photoemission spectra showed that the mean Cu valence of the films was decreased approximately from +2 to +1 by the irradiation. From these results we can find that ...

51

Total hemispherical emittance of niobium-1% zirconium fuel cladding for the SP-100 space reactor. Master's thesis  

Energy Technology Data Exchange (ETDEWEB)

Total hemispherical emittance was measured for the SP-100 reactor fuel cladding alloy (Nb-l% Zr). Based on a standard test method (ASTM C 835-82), experiments were conducted on a reference sample of oxidized stainless steel and then on a sample of actual cladding. The sample is heated in a vacuum by passing DC current through it until reaching equilibrium. Measurements are made of the electrical power dissipated in the sample and of the surface temperature. Using the Stefan-Boltzmann Law and some key assumptions concerning conductive and radiative heat transfer, the measured quantities are used to calculate emittance. Calculated values for unoxidized cladding range from 0.159 +/- 5.35% at 913 K to 0.200 +/- 4.51% at 1091 K. Highest value measured after onset of visible oxidation was 0.339 +/- 3.92% at 1269 K.... SP-100, Reactor, Emittance, Niobium, Fuel cladding, Emissivity.

1992-12-01

52

Spectral dependence of absorption photoinduced in a Bi{sub 12}TiO{sub 20} crystal by 532-nm laser pulses  

Science.gov (United States)

The spectral dependences of absorption photoinduced in a pure bismuth titanium oxide crystal by 532-nm laser pulses are studied. It is shown that optical absorption in the crystal in the range from 492 to 840 nm increases with increasing exposure. The photoinduced absorption relaxes in the dark for more than 60 hours. A model of photoinduced absorption is proposed which assumes the population of two trap centres with the normal energy distribution law for the concentrations of electrons photoexcited from donors to the conduction band. This model well describes the spectral dependences of photoinduced absorption by using the average ionisation energies of the traps E{sub 1} = 1.60 eV and E{sub 2} = 2.57 eV. The model is used to estimate the increase in the photorefractive sensitivity of a bismuth titanium oxide crystal in the near IR region, which was earlier observed after exposing the crystal to visible radiation. It is ...

2007-11-30

53

Safety analysis report: packages. Pu oxide and Am oxide shipping cask (Packaging of fissile and other radioactive materials. Final report  

Energy Technology Data Exchange (ETDEWEB)

The PuO/sub 2/ cask or SP 5320-2 and 3 cask is designed for surface shipment of americium or plutonium. The cask design was physically tested to demonstrate that it met the criteria specified in US ERDA Manual Chapter 0529, and Chapter I, Interstate Commerce Commission. The package has been assessed for transport of up to 357 grams of plutonium (403 grams PuO/sub 2/ powder) and up to 176 grams of americium (200 grams AmO/sub 2/ powder), having a maximum decay heat of 203 watts. Criticality evaluation alone would allow the shipment as Fissile Class II but the radiation level of the cask, measured at the time of shipment, may exceed 50 mrem/h at the surface and require shipment as Fissile Class III. Sample calculations address only the more restrictive of the two materials, which in most cases is /sup 238/PuO/sub 2/.

1980-05-01

54

High efficiency direct thermal to electric energy conversion from radioisotope decay using selective emitters and spectrally tuned solar cells  

International Nuclear Information System (INIS)

Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source.

1993-08-23

56

Obtainment of lanthanum oxide by fractionated precipitation method  

International Nuclear Information System (INIS)

... ammonium compounds benzilic acid chemical preparation lanthanum oxides

1979-01-01

58

The prooxidant-antioxidant homeostasis in Guinea pigs after exposure to fractionated low-low X-radiation and correction of its disturbances with antioxidant complex treatment  

International Nuclear Information System (INIS)

The state of prooxidant-antioxidant homeostasis in Guinea pigs exposed to whole-body fractionated X-irradiation (5 fractions of 0.2 Gy at a 24 hr interval, up to total dose of 1.0 Gy, at a dose rate of 0.425 R/min) and a possibility of its disturbance correction with the complex of vitamins C, E and P was studied. Accumulation of primary and secondary lipid peroxidation products, decrease of the ascorbic acid content, increase of the content of its oxidized forms (dehydroascorbic acid and diketogulonic acid) in radiosensitive and radioresistant organs were found. Antioxidant complex administration reduced the disturbances of prooxidant-antioxidant homeostasis, but did not provide complete normalization.

59

Studies on application of radiation and radioisotopes -The application of irradiation techniques for food preservation and process improvement-  

Energy Technology Data Exchange (ETDEWEB)

The project was designed to solve the infra structural problem required for commercialization of food irradiation. In improvement of physical properties of corn starch, gamma irradiation was effective for increasing glucose productivity and for substituting traditional modified starches (acid modified starch, oxidized starch). In immobilization of microorganisms, the mass production method of natural red pigment was developed by using immobilized mold pellets. In Korean medicinal plants, 10 kGy gamma irradiation was effective for improving sanitary quality and increasing extraction yield. In evaluation of wholesomeness, gamma irradiated red ginseng could be safe on the genotoxic point of view. And also, six items of irradiated foods approved for human consumption from Korea ministry of health and welfare in May 19, 1995. 30 figs, 20 tabs, 54 refs. (Author).

1995-07-01

60

Recent observations on the evolution of secondary-phase particles in zircaloy-2 under irradiation in a BWR to high burn-up  

Energy Technology Data Exchange (ETDEWEB)

The influence of radiation on the corrosion of the fuel claddings in a Light Water Reactor (LWR) has been the subject of many investigations, and different aspects of the overall phenomena have been studied by different techniques. Analysis of the evolution of Secondary-Phase Particles (SPPs) for different periods of immersion of the cladding in the reactor enables the rate of corrosion to the structure of the material to be correlated. In the case of Zircaloy-2 in a Boiling Water Reactor (BWR), SPPs are dissolved under irradiation, and their dissolution affects the rate of oxidation and other correlated phenomena. In recent studies, the Zircaloy-2 in claddings loaded in the Leibstadt BWR are analysed after one, three and five cycles. Results are presented, and give an account of the changes which occurred in the materials under irradiation. (authors)

2000-07-01

61

Photosensitization by drugs. [Ultraviolet radiation  

Science.gov (United States)

uv irradiation (365 nm) of air-saturated methanol solutions of 20 drugs absorbing in the 300 to 400 nm region gave rise to oxygen uptake, as determined with a polarographic oxygen electrode. The drugs were tested for photosensitizing capability by either a Type I (free radical) or a Type II (single molecular oxygen) mechanism. This testing was done by the inclusion of either acrylamide or 2,5-dimethylfuran in the irradiated drug solution, with observation of the subsequent polymerization or oxidation, respectively. Phenothiazine and thiazide derivatives appear capable of photosensitization by both mechanisms; promethazine, trifluoperazine, and furosemide show relatively high reactivity. Diazepam (weak), hexachlorophene, aminacrine, pyrilamine, tetracycline, demeclocyline, quinine, and anthracene (strong) react only by a Type II mechanism, with a photosensitizing efficiency increasing in the order given. A correlation appears to exist with reports of in vivo ...

1977-09-01

62

Neutron resonances in "1"0"0Mo and valence neutron capture  

International Nuclear Information System (INIS)

Neutron resonance interactions with "1"0"0Mo were studied at a time-of-flight facility. The transmission of two oxide samples (97.4% "1"0"0Mo) was measured at a 78.20 m flight path and the neutron capture cross section was measured at 40.12 m. Resonance analyses yielded parameters of 124 resonances. Capture #gamma#-ray spectra from 11 resolved resonances were measured with a Ge(Li) detector at a 10.45 m flight path. In contrast to neighboring nuclei, partial radiation widths of strong p-wave resonances are not in agreement with valence model predictions.

63

Interactions of SO{sub x} and NO{sub x} with soot  

Energy Technology Data Exchange (ETDEWEB)

Studies of the adsorption of oxides of sulfur and nitrogen, and their coadsorption, on black carbon in the form of n-hexane soot have been carried out by microgravimetry, EPR and FTIR spectroscopy over a wide range of experimental conditions. The mechanisms of adsorption of O{sub 2} and NO{sub 2} are entirely different, as reflected by adsorption isotherms, the behavior of carbon`s unpaired electrons, the spectral features of surface species formed, mass changes during adsorption-desorption cycles, and an essential lack of competition for surface sites. Significant effects of temperature, water, SO{sub 2} and NO{sub 2} concentration, O{sub 2}, simulated solar radiation, and the presence of trace metals, have been observed and interpreted.

1996-10-01

64

Considerations referring to chemical descaling of filmed carbon steels  

International Nuclear Information System (INIS)

Under operational conditions in nuclear power plants, the carbon steel components of the primary and secondary circuits react with high temperature cooling agent forming several iron oxides and oxyhydroxides. These deposits can result in tubes' constrictions, pitting and intergranular corrosion and finally to heat transfer reducing and increasing of radiation fields around the circuits, as well. The descaling process involves the chemical dissolution of the corrosion deposits by means of diluted organic acidic solutions containing usually a carboxylic acid, a reductant and one or more corrosion inhibitors. To evaluate the removing rates of these superficial films two types of methods were used, the gravimetric and potentiodynamic techniques. By correlating the experimental results, we established the chemical composition of descaling solution and two models of mechanisms applicable to our specific conditions. (authors)

2009-10-12

65

Advanced oxidation process based on ozone/electron beam irradiation for treating groundwater  

International Nuclear Information System (INIS)

There are several methods of generating OH free radicals from ozone and/or hydrogen peroxide and ultraviolet light. They all have in common that the OH free radicals originate in one single source only whereas in the combination of ozone with ionizing radiation two simultaneous working sources for the OH free radicals exist. The resulting higher OH free radical concentration makes this process especially apt for the remediation of low level contaminated groundwater as for example trichloroethylene (TCE) contamination in the sub-ppm range. A cost comparison between O_3/UV and O_3/electron beam for remediation of a groundwater contaminated with 100 ppb TCE indicated that for a throughput of about 5 million gallons/day the O_3/electron beam process is more cost-effective. (authors).

66

A routine chemical dosimetric system using the modified ceric sulphate dosimeter  

International Nuclear Information System (INIS)

The radiolytic reduction of the Ce4+ in a 0.8N sulfuric acid was examined, with the objective of measuring large radiation doses. the ceric sulphate dosimeter was tested in the range from 1 to 20kGy. The 0.01 M sodium oxalate solution was chosen instead of the arsenious oxide solution (used in the conventional method), in order to obtain a less expensive dosimetric system than that normally use for routine chemical dosimetry. The absorption spectrum of the Ce"4"+ solution presents an absorption peak at 370 nm; the obtained molar extinction coefficients of Ce"4"+ and Ce"3"+ were 5670 and 2.7 M"-"1 cm"-"1 respectively. The purpose of this work was to establish a simple, reliable and inexpensive routine chemical dosimetric system for high doses.

1994-10-01

67

Radiation Chemistry of Aqueous Solutions Related to Nuclear Reactor Systems and Spent Fuel Management  

International Nuclear Information System (INIS)

In this thesis the rate constants for a number of radical reactions in aqueous solution have been studied in a wide temperature range. The reactions of H with H_2O_2, OH and HO_2 and the reactions of HO_2 with OH, Fe"2"+ and Cu"2"+ have been studied. For each reaction rate constants have been determined as a function of temperature using the technique of high temperature, high pressure (HTP) pulse radiolysis. The rate constants were obtained by fitting a kinetic computer model to the experimental data. From an Arrhenius plot the activation energy of each reaction was determined. The data determined in this way are important for modeling of radiolysis in nuclear light water reactors. A previously developed model for calculation of the effect of water radiolysis products on oxidation and dissolution of spent nuclear fuel has been improved. In the new model, called TraRaMo, simultaneous transport by diffusion and chemical reactions induced by radiolysis can be ...

2003-01-01

68

Ionising radiation effects on food packaging  

International Nuclear Information System (INIS)

The main aim of any food irradiation treatment is to guarantee the best safe quality of the products, reducing the spreading risk ("cross-contamination") for several food-associated diseases. Actually, over 40 countries provide clearances for the treatment of about 45 different types of foodstuffs. EU has to homogenise the situation within the associated States. With the European directive 1999/2/EC Italy, as other EU countries, already has brought into force their regulations to comply. The current Italian regulation on irradiation treatment of foodstuffs is referred since 1996 as follows: a) potatoes, onions and garlic; b) spices, herbs and condiments microbial. The new (April 2001) Italian law allows the possibility to ask for special permission of treatment for other foodstuff which is possible to treat in other E.U. countries. Large majority of foods are submitted to irradiation treatment after they have been packaged. In Dutch cases the study of radiation ...

2001-10-22

69

Corrosion studies on selected packaging materials for disposal of high level wastes  

International Nuclear Information System (INIS)

In order to qualify corrosion resistant materials for high level waste (HLW) packagings acting as a long-term barrier in a rock salt repository, the corrosion behaviour of the preselected materials Ti 99.8-Pd, Hastelloy C4 and two unalloyed steels was investigated. The resistance of the materials to general corrosion, local corrosion and stress corrosion cracking was examined under postulated accident conditions in the repository by long-term immersion tests of up to 4 years duration and electrochemical methods. The parameters investigated were different salt brines, temperatures of 90 deg. C, 170 deg. C and 200 deg. C as well as a gamma radiation field of 10"3Gy/h (10"5rad/h). Among the materials studied, Ti 99.8-Pd exhibited the highest corrosion resistance. This material corroded at a very low rate (radiation, and proved to be resistant to local corrosion and stress corrosion cracking. Hastelloy C4 ...

1987-05-01

70

Transition of hydrated oxide layer for aluminum electrolytic capacitors  

Energy Technology Data Exchange (ETDEWEB)

A hydrous oxide film for the application as dielectric film is synthesized by immersion of pure aluminum in hot water. From a Rutherford backscattering analysis, the ratio of aluminum to oxygen atoms was found to be 3:2 in the anodized aluminum oxide film, and 2:1 in the hydrous oxide layer. Anodization of the hydrous oxide layer was more effective for the transition of amorphous anodic oxides to the crystalline aluminum oxides.

2007-03-25

71

Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles  

International Nuclear Information System (INIS)

Some of the Indian pressurized heavy water reactors (PHWRs) which use Stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit have encountered high radiation fields in the moderator system due to "6"0Co. Release of particulate Stellite is responsible for the hotspots in addition to the general uniform contamination of internal surfaces with "6"0Co. Extensive laboratory studies have shown that it is possible to dissolve these Stellite particles by adopting a three-step redox process with permanganic acid as the oxidizing agent. These investigations with inactive Stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The susceptibility of Stellite to corrode or dissolve was found to depend on the concentration of the permanganate, pH and temperature of the ...

2011-06-01

72

Integrated Optics Anisotropic Waveguides and Devices  

Science.gov (United States)

... silicon oxide (BSO), bismuth germanium oxide (BGO), and bismuth titanium oxide (BTO). These crystals are electro-optic, optically active, ...

1989-04-30

73

The interaction of alcohol radicals with human hemoglobin. Pt. 1. Spectral properties of hemoglobin in the visible range  

International Nuclear Information System (INIS)

Aqueous deoxyhemoglobin solutions (2 mg/ml) were gamma-irradiated by a "6"0Co source in the presence of methanol, ethanol, 1-butanol and t-butanol under N_2O or argon. The effects of the interaction of the particular alcohol radical species with hemoglobin were determined according to the detected spectral alterations in the visible range. The amounts of stable final products in the form of methemoglobin (MetHb) and the sum of hemichromes and cholehemichromes (Hemichr) were estimated in irradiated preparations. For preparations irradiated under N_2O, the radiation yield for MetHb formation was three-fold lower in the presence of ethanol and 1-butanol [G(MetHb) = 0.33[ compared with preparations irradiated in the presence of t-butanol or without alcohol [G(MetHb) = 1.00[. The yield of hemichromes and cholehemichromes in preparations irradiated under N_2O increased in the order: ethanol (G = 0.38), 1-butanol (B = 0.52), t-butanol (G = 0.59), and in the absence of ...

74

Environmental pollutant isotope measurements and natural radioactivity assessment for North Tushki area, south western desert, Egypt  

International Nuclear Information System (INIS)

Natural radioactive materials under certain conditions can reach hazardous radiological levels. The natural radionuclide ("2"3"8U, "2"3"2Th, "4"0K) contents of rock samples at various locations in the North Tushki area were investigated using gamma-spectrometric analysis. Estimates of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The equivalent radium (R_e_q) and the external hazard index (H_e_x) which resulted from the natural radionuclides in soil are also calculated and tabulated. The studied samples have been collected from various rock exposures in the North Tushki area. The distribution of major oxides, U and Th were studied. It is found that the enrichment and depletion of the major oxides are mainly due to the effect of hydrothermal alteration, which caused mobility of some major oxides, which increases some elements and decreases others. It is ...

2002-09-01

75

Combined photochemical-biological processes for treatment of unleaded gasoline oxygenates : MTBE, ETBE and TAME  

Energy Technology Data Exchange (ETDEWEB)

A study was conducted to determine the feasibility and the opportunity of photochemical pretreatment on the biodegradation and detoxification of Methyl Tert Butyl Ether (MTBE), Ethyl Tert Butyl Ether (ETBE) and Tert Amyl Methyl Ether (TAME), the most common oxygenates used as octane enhancers in unleaded gasoline. The production, storage, uses and disposal of oxygenates result in an unknown amount of groundwater pollution. Because of their high solubility, MTBE, ETBE and TAME are detected in large portions in saturated zones of aquifers. The biodegradation of these oxygenates is difficult and slow, and information regarding their biodegradability is scarce. Photo-decomposition of oxidants under appropriate UV radiation has been shown to be very effective because the hydroxyl radicals produced possess high oxidation potential. In this study, the H{sub 2}O{sub 2}/UV process was used to generate hydroxyl radicals. Maximal ...

1998-10-01

76

Combined photochemical-biological processes for treatment of unleaded gasoline oxygenates : MTBE, ETBE and TAME  

International Nuclear Information System (INIS)

A study was conducted to determine the feasibility and the opportunity of photochemical pretreatment on the biodegradation and detoxification of Methyl Tert Butyl Ether (MTBE), Ethyl Tert Butyl Ether (ETBE) and Tert Amyl Methyl Ether (TAME), the most common oxygenates used as octane enhancers in unleaded gasoline. The production, storage, uses and disposal of oxygenates result in an unknown amount of groundwater pollution. Because of their high solubility, MTBE, ETBE and TAME are detected in large portions in saturated zones of aquifers. The biodegradation of these oxygenates is difficult and slow, and information regarding their biodegradability is scarce. Photo-decomposition of oxidants under appropriate UV radiation has been shown to be very effective because the hydroxyl radicals produced possess high oxidation potential. In this study, the H_2O_2/UV process was used to generate hydroxyl radicals. Maximal oxygenates ...

1998-10-01

77

The Use of Medical Images in Planning and Delivery of Radiation Therapy  

UK PubMed Central (United Kingdom)

Abstract The authors provide a survey of how images are used in radiation therapy to improve the precision of radiation therapy plans, and delivery of radiation treatment. In contrast...Full Text Available

1997-09-01

79
80

Animal Models for Radiation Injury, Protection and Therapy  

Science.gov (United States)

... radiation during clinical therapy and exposures due to radiation accidents or attacks, in which the doses are uncontrolled ... only be used off-label in victims of radiation accidents or attacks. The idea...

82

Update on the oxidative stress theory of aging: Does oxidative stress play a role in aging or healthy aging?  

UK PubMed Central (United Kingdom)

The oxidative stress theory of aging predicts that manipulations that alter oxidative stress/damage will alter aging. The gold standard for determining whether aging is altered is lifespan,...Full Text Available

2010-03-01

87

Characterization and catalytic oxidation activity of uranium-bismuth mixed oxides  

International Nuclear Information System (INIS)

Bi-U mixed oxides were synthesized by two methods and characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The samples were tested for the catalytic oxidation of carbon monoxide by oxygen. A stepwise redox mechanism consistent with the kinetic results is proposed. (orig.).

89

Radiolytic stabilization of industrial poly(methyl methacrylate); Estabilizacao radiolitica do poli(metacrilato de metila) industrial  

Energy Technology Data Exchange (ETDEWEB)

Poly(methyl methacrylate), PMMA, Acrigel, a Brazilian polymer, is used in the manufacture of medical supplies sterilisable by ionizing radiation. However, when PMMA is gamma-irradiated it undergoes main chain scissions, which promote molecular degradation causing reduction in its physical properties. Therefore, radiolytic stabilization of PMMA is important for to become it commercially radio sterilisable. In this work we investigated the radiolytic stabilization of PMMA by using HALS (Hindered Amine Light Stabilizer) additive, commercially used for photo and thermo oxidative stabilization of polymers. The investigation of the radiation-induced main chain scissions was carried out by viscometric method. The additive added to the polymer system at 0.3 % w/w promotes a molecular radioprotection of 61%. That means a reduction of G value (scissions/100 eV) from 2.6 to 1.0. In addition, the glassy transition temperature (Tg) of ...

2005-03-15

90

Tritium Oxide Content Control  

International Science & Technology Center (ISTC)

Development of Method and Technical Project of the Plant for Thermo-Vacuum Desorption of Tritium Oxide (HTO) from the Environmental Samples

91

Sputter Deposition of Yttrium-Oxides.  

Science.gov (United States)

... Accession Number : ADD257320. Title : Sputter Deposition of Yttrium-Oxides. Descriptive Note : Journal article,. Corporate ...

93

Laboratory evaluation of the feasibility of chemical oxidation processes for treatment of contaminated groundwaters. Final report  

Energy Technology Data Exchange (ETDEWEB)

Chemical oxidation is a treatment technology that uses powertul chemical oxidizers to destroy organic contaminants. Typical oxidizers used in chemical oxidation processes include ozone, hydrogen peroxide, chlorine, and potassium permanganate. The chemical reaction products are usually simple organic compounds, such as carboxylic acids, and/or inorganic compounds, such as carbon dioxide, water, and simple inorganic complexes (e.g., chloride salts, in the case of chemical oxidation treatment of chlorinated solvents).

1995-09-01

94

Effect of hydrogen sulfide on chemical looping of coal-derived synthesis gas over bentonite-supported metal---oxide oxygen carriers  

Science.gov (United States)

The effect of hydrogen sulfide (H2S) on the chemical looping combustion of coal-derived synthesis gas with bentonite-supported metal oxidesssuch as iron oxide, nickel oxide, manganese oxide, and copper oxideswas investigated by thermogravimetric analysis, mass spectrometry, and X-ray photoelectron spectroscopy (XPS). During the reaction with synthesis gas containing H2S, metal-oxide oxygen carriers were first reduced by carbon monoxide and hydrogen, and then interacted with H2S to form metal sulfide, which resulted in a weight gain during the reduction/sulfidation step. The reduced/sulfurized compounds could be regenerated to form sulfur dioxide and oxides during the oxidation reaction with air. The reduction/oxidation capacities of iron oxide and nickel oxide were not affected by the presence ...

2009-01-01

95

Statistical cut-off criterion  

International Nuclear Information System (INIS)

... radiation effects human populations low dose irradiation neoplasms radiation

1980-01-01

96

Radiation protection and the management of radioactive waste in the oil and gas industry  

CERN Document Server

Radiation protection and the management of radioactive waste in the oil and gas industry

2003-01-01

98

Higher harmonics of spontaneous radiation of ultrarelativistic channeled particles  

International Nuclear Information System (INIS)

The case of spontaneous radiation of channeled ultrarelativistic particles is considered when the dipolarity condition is not satisfied. The change of the particle longitudinal velocity affecting the maximum radiation frequency is included. The angular and frequency characteristics of the radiation for superhigh energies are studied for the first time. It is shown that there is an optimum energy at which the radiation density is maximum. The influence of the angle at which electrons enter a crystal and of the beam divergence on the radiation is investigated. The problem of quasichanneled particle radiation and also the radiation in axis-plane transitions are considered. (author).

1980-06-01

100

Contribution to the radiation preparation of wood-plastic materials. Pt. 7  

International Nuclear Information System (INIS)

... odd nuclei organic compounds radiation effects radioisotopes synthesis

1974-01-01

101

Contribution to the radiation preparation of wood-plastic materials. Pt. 6  

International Nuclear Information System (INIS)

... compounds polymers polyolefins polyvinyls radiation effects SYNTHESIS.

1974-01-01

102

Contribution to the radiation preparation of wood-plastic materials Pt. 3  

International Nuclear Information System (INIS)

... compounds plants radiation effects radioisotopes reaction kinetics trees

1974-01-01

103

Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy  

CERN Document Server

Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy

2002-01-01

104

? j -  

Science.gov (United States)

duced and spontaneous radiation. The amount of polarization is ... of the induced and spontaneous radiation patterns. Therefore ...

105

Systematics of average radiative width of heavy nuclides  

Energy Technology Data Exchange (ETDEWEB)

Systematics of neutron capture radiative width were studied in the target element range from Th to Cm. Reduced radiative widths were analyzed with a simple radiative width formula based on E1 transition. Average radiative width is presented with the standard deviation of 15%. (author)

1999-03-01

106

Oxidation of Propylene with Oxygen and Air in a Barrier Discharge in the Presence of Octane  

British Library Electronic Table of Contents (United Kingdom)

Oxidation of propylene with oxygen, air and a mixture of nitrogen?oxygen in a barrier discharge is investigated. The selectivity towards formation of propylene oxide in pure oxygen is shown to be as high as 45 wt% and the propylene conversion ratio is found to be 12.9 wt%. In the oxidation with air, the propylene oxide selectivity is 23 wt%, while the conversion is 7.5 wt%. The values of propylene conversion and selectivity towards formation of propylene oxide in a barrier discharge are consistent with those obtained by the thermocatalytic methods for production of propylene oxide.

2011-01-01

107

Structure and kinetics of Sn whisker growth on Pb-free solder finish  

Energy Technology Data Exchange (ETDEWEB)

Standard Leadframes used in surface mount technology are finished with a layer of eutectic SnPb for passivation and for enhancing solder wetting during reflow. When eutectic SnPb is replaced by Pb-free solder, especially the eutectic SnCu, a large number of Sn whiskers are found on the Pb-free finish. Some of the whiskers are long enough to become shorts between the neighboring legs of the leadframe. How to suppress their growth and how to perform accelerated test of Sn whisker growth are crucial reliability issues in the electronic packaging industry. In this paper, we report the study of spontaneous Sn whisker growth at room temperature on eutectic SnCu and pure Sn finishes. Both compressive stress and surface oxide on Sn are necessary conditions for whisker growth. Structure and stress analyses by using the micro-diffraction in synchrotron radiation are reported. Cross-sectional electron microscopy, with samples prepared by focused ion beam, ...

2002-07-11

108

Sludge stabilization at the Plutonium Finishing Plant, Hanford Site, Richland, Washington  

Energy Technology Data Exchange (ETDEWEB)

This Environmental Assessment evaluates the proposed action to operate two laboratory-size muffle furnaces in glovebox HC-21C, located in the Plutonium Finishing Plant (PFP), Hanford Site, Richland, Washington. The muffle furnaces would be used to stabilize chemically reactive sludges that contain approximately 25 kilograms (55 pounds) of plutonium by heating to approximately 500 to 1000{degrees}C (900 to 1800{degrees}F). The resulting stable powder, mostly plutonium oxide with impurities, would be stored in the PFP vaults. The presence of chemically reactive plutonium-bearing sludges in the process gloveboxes poses a risk to workers from radiation exposure and limits the availability of storage space for future plant cleanup. Therefore, there is a need to stabilize the material into a form suitable for long-term storage. This proposed action would be an interim action, which would take place prior to completion of an Environmental Impact ...

1994-10-01

109

Quantitative monitoring of the fluorination process by neutron counting  

Energy Technology Data Exchange (ETDEWEB)

Plutonium metal is produced by reducing PuF{sub 4} prepared from PuO{sub 2} by fluorination. Both fluorination and reduction are batch processes at the Los Alamos Plutonium Facility. The conversion of plutonium oxide to fluoride greatly increases the neutron yield, a result of the high cross section for alpha-neutron ({alpha},n) reactions on fluorine targets compared to the (more than 100 times) smaller {alpha},n yield on oxygen targets. Because of the increase, total neutron counting can be used to monitor the conversion process. This monitoring ability can lead to an improved metal product, reduced scrap for recycle, waste reduction, minimized reagent usage, and reduce personnel radiation exposures. A new stirred-bed fluorination process has been developed simultaneously with a recent evaluation of an automated neutron-counting instrument for quantitative process monitoring. Neutrons are counted with polyethylene-moderated {sup 3}He-gas ...

1993-12-31

110

Investigation of natural radionuclides in selected NORM-samples  

International Nuclear Information System (INIS)

A programme has been initiated by the Coordinating Office for Monitoring of enhanced natural radioactivity of the Federal Office for Radiation Protection to investigate different kinds of sample materials with enhanced naturally occurring radioactivity (NORM) such as scales from oilfield and naturally gasfield pipes, blast furnace sludge and sinter dust from the production of pig iron, as well as bauxit and red mud from the production of aluminium oxide. The aim of these investigations is to find proper preparation and measuring methods which allow, in particular, a sample treatment with optimised effort combined with a reliable determination of the specific activities of the dominating radionuclides. Of particular interest is the method of gamma-ray spectrometry, since this method has been used for most of our studies of sample materials. Due to different compositions of calibration and NORM-samples, e.g. different densities, and the analysis ...

2005-09-20

111

Investigation of a mineral melting cupola furnace. Part II. Mathematical modeling  

Energy Technology Data Exchange (ETDEWEB)

A mathematical model of a mineral melting cupola furnace for stone wool production has been developed for improving cupola operation. The 1-D, first-engineering-principles model includes mass and heat balances for the gas phase, five solid phases, and four liquid phases. The gas and solid/liquid phases flow countercurrently. Seven chemical reactions account for the conversions of coke, iron oxide, limestone, and gaseous species. The heterogeneous reactions of coke conversion are limited by both kinetics and mass transport. Heat transfer between phases is modeled including both convection and radiation. The model predicts gas concentrations; mass flow rates; and temperature profiles of the solid, melt, and gas in the cupola, as well as heat loss to the water-cooled walls. Inputs to the model include the coke, rock, and blast air properties, the blast air amount, and the coke percentage in the charge. The unknown model parameters are estimated on ...

2003-12-24

112

Endonuclease IV of Escherichia coli is induced by paraquat  

International Nuclear Information System (INIS)

The addition of paraquat (methyl viologen) to a growing culture of Escherichia coli K-12 led within 1 hr to a 10- to 20-fold increase in the level of endonuclease IV, a DNase for apurinic/apyrimidinic sites. The induction was blocked by chloramphenicol. Increases of 3-fold or more were also seen with plumbagin, menadione, and phenazine methosulfate. H_2O_2 produced no more than a 2-fold increase in endonuclease IV activity. The following agents had no significant effect: streptonigrin, nitrofurantoin, tert-butyl hydroperoxide, #gamma# rays, 260-nm UV radiation, methyl methanesulfonate, mitomycin C, and ascorbate. Paraquat, plumbagin, menadione, and phenazine methosulfate are known to generate superoxide radical anions via redox cycling in vivo. A mutant lacking superoxide dismutase was unusually sensitive to induction by paraquat. In addition, endonuclease IV could be induced by merely growing the mutant in pure O_2. The levels of endonuclease IV in uninduced or ...

113

Effects of ionizing radiation on properties of monolayer and multilayer flexible food packaging materials  

International Nuclear Information System (INIS)

Volatile compounds produced in flexible food packaging materials (LDPE, EVAc, PET/PE/EVOH/PE) during electron beam irradiation were isolated by purge and trap technique and identified by combined gas chromatography-mass spectrometry (GC/MS), after thermal desorption and concentration. For comparison purposes non-irradiated films were also studied. Film samples were irradiated at low (5 kGy, corresponding to cold pasteurization), intermediate (20 kGy, corresponding to cold sterilization) and high (100 kGy) doses. It was observed that a number of volatile compounds are produced after irradiation in all cases. Furthermore the amounts of all volatile compounds increase with increasing irradiation dose. Both primary (methyl-derivatives etc.) as well as secondary i.e. oxidation products (ketones, aldehydes, alcohols, carboxylic acids etc.) are produced upon irradiation. These products may affect organoleptic properties and thus shelf-life of prepackaged irradiated foods. ...

1999-05-01

114

Heavy fuel oil combustion in a cylindrical laboratory furnace: measurements and modeling  

Energy Technology Data Exchange (ETDEWEB)

The finite-volume based commercial CFD-code Fluent was used to simulate the reacting flow in a heavy fuel oil fired laboratory furnace. Both the standard {kappa}-{epsilon} turbulence model and the Reynolds stress model (RSM) were tested. The combustion model was based on the conserved scalar (mixture fraction) and prescribed probability density function approach. The heavy fuel oil droplet trajectories were predicted by solving the momentum equations for the droplets using the Lagrangian treatment. The soot distribution in the furnace was calculated by solving a transport equation for the soot mass fraction. Simple expressions for the soot formation and oxidation rates were employed. The radiation heat transfer equation was solved using the finite volume method. The formation of thermal NO from molecular nitrogen was modeled according to the extended Zeldovich mechanism. Fuel-based NO was modeled assuming that all the nitrogen in the fuel is ...

2005-03-01

115

CHEMICAL TECHNOLOGY DIVISION, UNIT OPERATIONS SECTION MONTHLY PROGRESS REPORT, JULY 1960  

Science.gov (United States)

A critical review of the literature revealed no experiments on uranyl ion transfer from an aqueous to a tributyl phosphate phase which positively measured the kinetics of the chemical reaction at the interphase. Drawing isorhythmic lines on a three component diagram gives a complex correlation for the compaction of three sizes of glass beads. Neither the use of thoria sols nor high feed solution concentrations of thorium nitrate gave any significant increase in mean particle diameters over those obtained from nitrate solutions of lower concentrations in flame denitration. A hydraulic film resistance has been detected in the anion exchange of uranyl sulfate into Dowex 2lK, and chloride elution was found to give a higher apparent uranium diffusion coefficient than nitrate elution. The rate of dissolution of mixed thorium-uranium oxides was determined as a function of the per cent of mixed oxides dissolved. Mixing in ...

1960-10-27

116

Development of internal dose estimation software on radiation protection  

International Nuclear Information System (INIS)

Objective: To develop a computerized method of internal dose estimation on radiation protection. Methods: Based on MIRD mathematic model of the organs and by means of the programming language of MS Visual Basic 6.0, a computer program of dose estimation in internal radiation was developed for radiation protection. Results: The computerized method of dose estimation for internal radiation was completed. Conclusions: This computerized method is very convenient for internal radiation dose estimation of several aspects. It can also be used in radiation accident. (authors)

2008-10-01

117

Surface intermediates in selective olefin oxidation and ammoxidation  

Energy Technology Data Exchange (ETDEWEB)

An investigation of the mechanism of the oxidation and ammoxidation of propylene was made. The products of the above reactions were acrylonitrile and acrolein for ammoxidation and oxidation, respectively. Also, the ammoxidation and oxidation of allyl alcohol, allyl amine, and their allylic deuterium substituted analogues was studied. It was concluded that oxidation and ammoxidation of propylene have the same rate determining step. Other conclusions about the reaction intermediates were also made.

1983-02-01

118

Electrochemical oxidation of drug residues in water by the example of tetracycline, gentamicin and Aspirin {sup trademark}  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical oxidation as a method to destroy drug residues like Aspirin {sup trademark}, tetracycline or gentamicin in water was investigated with C-Anode (modified by manganese oxides) and Pt Anode. The mechanism of Aspirin {sup trademark} and tetracycline oxidation and the influence of the biocide effect was observed using GC-MS and three different microbiological tests. In general the biological availability increases with progressive oxidation of the antibiotics. (orig.)

2003-07-01

119

The evaluation of risks from radiation  

International Nuclear Information System (INIS)

German translation of the publication 'The evaluation of risks from radiation' published in 1965 by the International Commission on Radiological Protection. In a survey, genetic and somatic risks from radiation are presented and explained. (HP).

1977-01-01

121

Role of Mast Cells in Early and Delayed Radiation Injury in Rat Intestine  

Science.gov (United States)

... mast cell staining; ref. 16). The severity of structural radiation injury was assessed using a histopathological radiation injury score ... ...

122

Radionuclide X-ray fluorescence analysis. 1: Excitation of X-ray fluorescense radiation by nuclear radiation  

Science.gov (United States)

The principles of radionuclide excitation of X-ray fluorescence radiation and its application in

1972-01-01

123

Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation  

Science.gov (United States)

This investigation describes the technique for the detection of the X-ray fluorescent radiation

1972-01-01

124

Radiation protection - an overview of the concept for radiation protection at work and the concept for environmental radiation protection  

International Nuclear Information System (INIS)

This book gives an overview of the entire field of radiation protection with the subject areas radioactivity, X-rays, UV radiation, laser beams and high-frequency electromagnetic fields. It deals graphically with the most important physical notions, the incidence, origin, properties and biological effects of types of radiation, administrative and practical protection measures and the code of rules governing them. Apart from fundamentals of radiation protection the emphasis on the following: natural radiation exposure, radiation exposure to radon, disaster relief plans in the environment of nuclear plant, the precautionary radiation protection system evolved after Chernobyl, radiation exposure through UV radiation devices, radio, RF communication, radar, microwave ovens and high-voltage transmission ...

1993-01-01

125

Structure and electronic studies of defects in amorphous silicon. Final report, March 1980-February 1981  

Science.gov (United States)

Basic research of the structure and electronic properties of a-Si:H is reported with particular emphasis on the role of defects. The main findings are as follows: (1) low defect density material can be deposited at a high rate using SiH/sub 4/ diluted in He or Ne. Using Ar or Kr results in a high defect density and columnar material; (2) an electrical bias during deposition modifies the band gap, hydrogen concentration and structure; (3) the clustering of hydrogen in the regions between the columns is confirmed; (4) hydrogen diffusion is observed by NMR; (5) the oxidation of an a-Si:H surface results in approx. 3 x 10/sup 11/ cm/sup -2/ dangling bonds at the interface; (6) auger recombination of photoexcited carriers is a significant non-radiative mechanism at low temperatures; (7) non-radiative recombination by diffusion and capture at dangling bonds is observed at temperatures above 50 to 100/sup 0/K; (8) the defect ...

1981-08-01

126

Oriented immobilization of proteins on grafted porous polymers  

Energy Technology Data Exchange (ETDEWEB)

The modification of polymers by radiation grafting has been utilized for several decades. The penetrability of gamma rays allows to modify the internal surfaces of porous materials retaining its mechanical properties. In recent years applications of these materials to obtain chromatographic supports and biocatalysts have been reported. In this work, we described the grafting of glycidyl methacrylate (GMA) onto a macroporous polysulfone polymer. Reproducible amount of grafting, from 10% to 60% was obtained by choosing favourable monomer concentration and gamma radiation doses from 6 kGy up. Afterwards, iminodiacetic acid (IDA) and amino phenyl arsine oxide (PAO) were covalently attached to the grafted polyGMA, in correspondence with the grafting degree. Later on, a recombinant histidin-patch thioredoxin protein (HP-rTrx) was immobilized onto this surface by two different ways, involving specific protein orientations. The ...

2003-08-01

127

Gamma radiation effects at color, antioxidant capacity and fatty acid profile in peanut (Arachis hypogaea L.)  

International Nuclear Information System (INIS)

Irradiation is efficient at extinction fungi contamination in peanuts. Peanuts have high biologic value protein, minerals, vitamin E, complex B, and high concentration of lipids. The objective of this research is to evaluate the gamma irradiation effect on color, total phenolic, antioxidant activity, and fatty acid profile in peanuts (Arachis hypogaea L.). Cultivars IAC-Tatu ST and IAC-Runner 886 were submitted to gamma radiation with doses of 5.0; 7.5; 10.0, and 15.0 kGy and storage at room temperature. There was no significant difference in the color of IAC-Tatu ST. However, significant difference was found in the luminosity and Chroma in IAC-Runner 886. Total fenolics differed from the control with 33.27 mg.g-1 and treatment dose of 10.0 kGy with 58.60 mg.g-1 in IAC-Tatu ST. This parameter not had significant difference in IAC-Runner 886 and the control with 51.59 mg.g-1. The antioxidant activity did not present significant difference with a dose of 10.0 kGy, ...

2011-01-01

128

Development of functional foods for radiation workers - Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Some fractions of Him-I and Him-II increased the proliferation of bone marrow cells irradiated {gamma}-ray(4Gray). Stimulation of macrophage cell line with herval extracts with the treatments of recombinant ...

2000-04-01

129

Development of food preservation and processing techniques by radiation  

International Nuclear Information System (INIS)

Development of food preservation and processing techniques by radiation was performed. Gamma irradiation at 2-10 kGy is considered to be an effective method to control pathogenic bacteria in species including Escherichia coli O157:H7. Gamma irradiation at 5 kGy completely eliminated pathogenic bacteria in beef. Gamma irradiation at such doses and subsequent storage at less than 4 deg C could ensure hygienic quality and prolong the microbiological shelf-life resulting from the reduction of spoilage microorganisms. Gamma irradiation on pre-rigor beef shortens the aging-period, improves tenderness and enhances the beef quality. And, a new beef processing method using gamma irradiation, such as in the low salt sausage and hygienic beef patty was developed. Safety tests of gamma-irradiated meats(beefs: 0-5 kGy; porks: 0-30 kGy) in areas such as genotoxicity, acute toxicity, four-week oral toxicity, rat hepato carcinogenesis and the anti oxidative ...

1988-04-18

130

The correlation between accelerated and field corrosion tests performed in carbon steel and weathering steel coupons, coated and non-coated; Correlacao entre ensaios acelerados e ensaios de campo em corpos-de-provas de aco carbono e aco patinavel, sem e com revestimento  

Energy Technology Data Exchange (ETDEWEB)

The performance of four different organic coating systems applied to carbon and weathering steel coupons has been assessed in this investigation. applied on the surface of carbon steel and weathering steel coupons. The coupons have been evaluated using five different tests, three field tests and two accelerated tests. The field tests were carried out at three atmospheric stations, located at COSIPA in Cubatao-SP, at Alto da Serra in Cubatao-SP and at Paula Souza in Sao Paulo city. The accelerated tests consisted of (a) exposure to alternate cycles of ultraviolet radiation/condensation combined with salt spray cycles (UVCON combined with Salt Spray) and of (b) exposure to alternate cycles of ultraviolet radiation/condensation combined with the Prohesion test. The performance of the coatings was assessed by visual observation and photographs, using a method based on ASTM D-610, ASTM D-714 and ASTM-1654 standards to rank them. The ...

2002-07-01

131

Synthesis, characterization and optical properties of a high NIR reflecting yellow inorganic pigment: Mo"6"+ doped Y_2Ce_2O_7 as a cool colorant  

International Nuclear Information System (INIS)

Full text: Pigments possessing the ability to confer high solar reflectance have received considerable attention in recent years. The inorganic class of NIR reflective pigments are mainly metal oxides and are primarily employed in two applications: (i) visual camouflage and (ii) reducing heat build up. More than half of the solar radiation consists of near-infrared radiation (52%), the remaining being 43% visible light and 5% ultraviolet radiation. Over heating due to solar radiation negatively affects comfort in the built environment and contributes substantially to electrical consumption for air conditioning and release of green house gases. A pigment which has strong reflections in the NIR region (780-2500 nm) can be referred to as a 'cool' pigment. However, most of the NIR reflective inorganic pigments particularly yellow (eg. cadmium yellow, lead chromate, chrome titanate ...

2010-11-24

132

Protein stability and resistance to oxidative stress are determinants of longevity in the longest-living rodent, the naked mole-rat  

UK PubMed Central (United Kingdom)

The widely accepted oxidative stress theory of aging postulates that aging results from accumulation of oxidative damage. Surprisingly, data from the longest-living rodent known, naked mole-rats [MRs;...Full Text Available

2009-03-03

133

Oxidative Stress and Longevity in Okinawa: An Investigation of Blood Lipid Peroxidation and Tocopherol in Okinawan Centenarians  

UK PubMed Central (United Kingdom)

Background. The Free Radical Theory of Aging mechanistically links oxidative stress to aging. Okinawa has among the world's longest-lived populations but oxidative stress in this...Full Text Available

2010-01-01

134

Mitochondrial function and redox control in the aging eye: Role of MsrA and other repair systems in cataract and macular degenerations  

UK PubMed Central (United Kingdom)

Oxidative stress occurs when the level of prooxidants exceeds the level of antioxidants in cells resulting in oxidation of cellular components and consequent loss of cellular function. Oxidative...Full Text Available

2009-02-01

135

Local inhibition of nitric oxide generation in man reduces blood flow in finger pulp but not in hand dorsum skin.  

UK PubMed Central (United Kingdom)

1. Nitric oxide generation is important in the regulation of resistance vessel tone. Until now, however, there has been no evidence of such a role for basal generation of nitric oxide in the skin microcirculation...Full Text Available

1996-01-15

136

Heterogeneous coupling of phenylethyne over Cu-Mg-Al mixed oxides. Influence of catalyst composition and calcination temperature on structural and catalytic properties  

Science.gov (United States)

The catalytic effects of copper-aluminium-magnesium oxides in the oxidative coupling of phenylethyne is described. The importance of surface properties as a redox site are discussed.

1997-07-01

137

Evolution of Nitrogen Oxide(s) during In Vivo Nitrate Reductase Assay of Soybean Leaves  

UK PubMed Central (United Kingdom)

Studies were conducted to quantitate the evolution of nitrogen oxides (NO(x)) from soybean [Glycine max (L.) Merr.] leaves during in vivo nitrate reductase...Full Text Available

1981-12-01

138

Effect of NAD+ on Malate Oxidation in Intact Plant Mitochondria 1  

UK PubMed Central (United Kingdom)

Potato tuber mitochondria oxidizing malate respond to NAD+ addition with increased oxidation rates, whereas mung bean hypocotyl mitochondria do not. This is traced to a low endogenous content...Full Text Available

1980-08-01

139

Community Structure of Ammonia-Oxidizing Bacteria within Anoxic Marine Sediments  

UK PubMed Central (United Kingdom)

The potential for oxidation of ammonia in anoxic marine sediments exists through anaerobic oxidation by Nitrosomonas-like organisms, utilizing nitrogen dioxide, coupling of nitrification,...Full Text Available

2003-03-01

140

Anodic oxide coatings on metals and anodic protection /2nd revised and enlarged edition/. Anodnye oksidnye pokrytiia na metallakh i anodnaia zashchita /2nd revised and enlarged edition/  

Energy Technology Data Exchange (ETDEWEB)

The theoretical principles underlying the formation of oxide and, in particular, anodic oxide coatings on metals produced by chemical oxidation, anodizing in solutions, and anodizing in cold plasmas are reviewed. The mechanisms and conditions of anodic oxidation are described, and the structure of anodic oxide coatings on aluminum, magnesium, beryllium, zinc, cadmium, iron, cobalt, nickel, titanium, zirconium, tantalum, and chromium alloys is examined. Attention is also given to various applictins of anodized coatings. 54 references.

1985-01-01

143

THE ENVIRONMENTAL MANAGEMENT AND CO-ORDINATION ACT, 1999  

Wastenet

Subject to the provisions of the Radiation Protection Act, the Authority, on the advice of ...(f) in collaboration with the Radiation Protection Board, conduct an ionising radiation monitoring programme and ...or document kept under the control of the Radiation Protection Board.

151

Application of gamma radiation  

International Nuclear Information System (INIS)

Described and discussed in this paper are radiation processes and their advantages over the conventional techniques. Radiation sterilization of medical products, food irradiation, wood plastic composites, and radiation treatment of sewage and waste waters are presented. The Philippine experience in using these technologies, its problems and barriers are also given. (ELC).

1985-12-10

154

The potential use of uranium oxides and uranium-bismuth mixed oxides in catalysis  

International Nuclear Information System (INIS)

The potential use of uranium in the field of catalysis is presented in the first part of this paper. Numerous applications of uranium binary oxides, as well as mixed oxides, are reviewed with a special emphasis on the role of U-Sb-O catalysts in selective oxidation (and ammoxidation) processes. Attempts are made to correlate the electronic structure of uranium, and especially the role that 5f electrons play in bonding, with its promising catalytic properties. In the second part, new data are given for uranium-bismuth mixed oxides in the catalytic oxidation of CO by O_2. Kinetic tests performed in a flow microreactor allow a mechanism to be proposed that involves the direct participation of lattice oxygen of the catalyst in the chemical process (redox mechanism). The high activity can be related to the ability of uranium to change reversibly its oxidation state. ...

155

Technology of GaAs metal-oxide-semiconductor solar cells  

Science.gov (United States)

The growth of an oxide interfacial layer was recently found to increase the open-circuit voltage (OCV) and efficiency by up to 60 per cent in GaAs metal-semiconductor solar cells. Details of oxidation techniques to provide the necessary oxide thickness and chemical structure and using ozone, water-vapor-saturated oxygen, or oxygen gas discharges are described, as well as apparent crystallographic orientation effects. Preliminary results of the oxide chemistry obtained from X-ray, photoelectron spectroscopy are given. Ratios of arsenic oxide to gallium oxide of unity or less seem to be preferable. Samples with the highest OVC predominantly have As(+3) in the arsenic oxide rather than As(+5). A major difficulty at this time is a reduction in OCV by 100-200 mV when the antireflection coating is vacuum deposited.

1977-01-01

156

Potential use of uranium oxides and uranium-bismuth mixed oxides in catalysis  

Energy Technology Data Exchange (ETDEWEB)

The potential use of uranium in the field of catalysis is presented in the first part of this paper. Numerous applications of uranium binary oxides, as well as mixed oxides, are reviewed with a special emphasis on the role of U-Sb-O catalysts in selective oxidation (and ammoxidation) processes. Attempts are made to correlate the electronic structure of uranium, and especially the role that 5f electrons play in bonding, with its promising catalytic properties. In the second part, new data are given for uranium-bismuth mixed oxides in the catalytic oxidation of CO by O/sub 2/. Kinetic tests performed in a flow microreactor allow a mechanism to be proposed that involves the direct participation of lattice oxygen of the catalyst in the chemical process (redox mechanism). The high activity can be related to the ability of uranium to change reversibly its oxidation ...

1987-07-01

157

Oxidative Damage and the Prevention of Age-Related Cataracts  

UK PubMed Central (United Kingdom)

PurposeCataracts are often considered to be an unavoidable consequence of aging. Oxidative damage is a major cause or consequence of cortical and nuclear cataracts, the most common...Full Text Available

2010-09-01

158

Oxidation of ethane by an Acremonium species.  

UK PubMed Central (United Kingdom)

Ethane oxidation was studied in ethane-grown resting cells (mycelia) of an Acremonium sp. and in cell-free preparations of such mycelia. From resting cell experiments evidence was found for a pathway...Full Text Available

1976-07-01

159

Metastability of yttrium-oxides.  

Science.gov (United States)

Metastable yttrium-oxide films are synthesized using reactive sputter deposition. The yttrium concentration of the as-deposited film is found to vary as a function of the sputter deposition rate. In addition to the synthesis of the cubic equilibrium phase...

1993-01-01

160

Double perovskite catalysts for oxidative coupling  

Energy Technology Data Exchange (ETDEWEB)

Alkali metal doped double perovskites containing manganese and at least one of cobalt, iron and nickel are useful in the oxidative coupling of alkane to higher hydrocarbons.

1991-01-01

161

Catalyst for the manufacture of acrylonitrile and methacrylonitrile  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a catalyst composition. It consists of the catalytic oxides of iron, bismuth, molybdenum and magnesium as essential components and optionally the oxides of cobalt, nickel, phosphorus and arsenic.

1989-09-05

162

Bicarbonate kinetics and predicted energy expenditure in critically ill children2  

UK PubMed Central (United Kingdom)

Background:To determine nutrient requirements by the carbon oxidation techniques, it is necessary to know the fraction of carbon dioxide produced during the oxidative...Full Text Available

2008-08-01

163

A Theoretical Solid Oxide Fuel Cell Model for - The NASA Glenn ...  

Science.gov (United States)

May 31, 2011 ... A Theoretical Solid Oxide Fuel Cell Model for System Controls and Stability Design AUTHOR(S): Kopasakis, George; Brinson, Thomas; Credle, ...

165

Radiobiology  

International Nuclear Information System (INIS)

This text-book (electronic book - multi-media CD-ROM) constitutes a course-book - author's collection of lectures. It consists of 13 lectures in which the reader acquaints with the basis of radiobiology: Introduction to radiobiology; Physical fundamentals of radiobiology; Radiation of cells; Modification of radiation damage of cells; Reparation of radiation damage of cells; Radiation syndromes and their modification; Radiation injury; Radiation damage of tissues; Effect of radiation on embryo and fetus; Biological effects of incorporated radionuclides; Therapy of acute irradiation sickness; Delayed consequences of irradiation; Radiation oncology and radiotherapy. This course-book may be interesting for students, post-graduate students of chemistry, biology, physics, medicine as well as for teachers, scientific workers ...

166

Radiation Therapy in Treating Patients With Prostate Cancer  

Science.gov (United States)

Prostate Cancer; Psychosocial Effects of Cancer and Its Treatment; Radiation Toxicity; Sexual Dysfunction and Infertility

2011-09-13

168

NAME=\\  

Wastenet

... Radiation Protection Products and Equipment Find and compare a variety of radiation protection products and equipment on the world's largest environmental industry portal. View product ...

170

Standards and guidances for limiting ionizing radiation exposure  

Energy Technology Data Exchange (ETDEWEB)

This chapter is concerned with standards and guidances for limiting radiation exposures. It is divided into three sections, each of which has several parts. Section 1: Ionizing Radiation -- Standards and Guidances Applicable to the Public: Part A, Radiation Protection Standards; Part B, Environmental Radiation Standards; Part C, Exempt Levels of Radioactivity; Part D, Protective Action Guides for Accidents. Section 2: Ionizing Radiation -- Standards Applicable to the Workplace. Section 3: Medical and Other Standards.

1992-12-31

171

Radiation protection in the operating room  

International Nuclear Information System (INIS)

On the basis of legally provided area dose measurements and time records of fluoroscopic examinations during the operation, radiation doses to medical personnel and patients are evaluated. Adequate radiation protection measures and a careful behaviour in the operating room keep the radiation exposure to the personnel below the maximum permissible exposure. Taking into account the continuous personnel radiation monitoring and medical supervision, radiation hazards in the operating room can be considered low.

172

Recycling of red mud waste for use as a catalyst for eliminating volatile organic compounds; Recyclage d'un dechet, une boue rouge, comme catalyseur pour l'elimination des composes organiques volatils  

Energy Technology Data Exchange (ETDEWEB)

Red mud is a waste product of the aluminium refining industry. It is composed of aluminium hydroxide and iron oxide. This study examined the feasibility of using red mud as a catalyst to eliminate volatile organic compounds in atmospheric pollutants. Volatile organic compounds can be eliminated by thermal oxidation between 600 and 1100 degrees C. However, the oxidation of volatile organic compounds can also be accomplished at lower temperatures (200 to 450 degrees C) if a catalyst is present. Currently, the low temperature destruction of volatile organic compounds is not widespread because of the difficulty in deactivating the catalyst. In this study, red mud was calcined in air at 500 degrees C. Under such conditions, the red mud converts to aluminium oxide and iron oxide. These 2 oxides are active and are carbon dioxide selective in the ...

2005-08-01

173

Survey of Radiation Protection Education and Training in Finland in 2003  

Energy Technology Data Exchange (ETDEWEB)

The current state and need for radiation protection training in Finland have been surveyed by the Radiation and Nuclear Safety Authority STUK. The survey sought to determine whether the current requirements for radiation protection training had been met, and to promote radiation protection training. Details of the scope and quality of present radiation protection training were requested from all educational institutes and organizations providing radiation protection training. The survey covered both basic and further training, special training of radiation safety officers, and supplementary training. The questionnaire was sent to 77 educational organization units, 66 per cent of which responded. Radiation workers and radiation safety officers were asked about radiation protection ...

2004-07-01

185

Inorganic chemistry of astatine  

International Nuclear Information System (INIS)

On the basis of experimental and extrapolated values the physico-chemical properties of astatine are reviewed considering all oxidation states.

186

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

Energy Technology Data Exchange (ETDEWEB)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-15

187

Influence of MeV electron irradiation on the properties of by ion implantation hydrogenated polysilicon TFTs  

International Nuclear Information System (INIS)

The influence of MeV electrons irradiation on the gate oxide layers of hydrogenated polysilicon thin film transistors (TFTs) was investigated by measuring gate leakage currents and threshold voltages. The experimental data revealed a decrease of oxide trap density and increase of positive oxide charge. Improvement in the interface roughness and in the oxide quality near the bottom interface was observed.

2006-02-01

191

Fouling Study of Silicon Oxide Pores Exposed to Tap Water  

Energy Technology Data Exchange (ETDEWEB)

We report on the fouling of Focused Ion Beam (FIB)-fabricated silicon oxide nanopores after exposure to tap water for two weeks. Pore clogging was monitored by Scanning Electron Microscopy (SEM) on both bare silicon oxide and chemically functionalized nanopores. While fouling occurred on hydrophilic silicon oxide pore walls, the hydrophobic nature of alkane chains prevented clogging on the chemically functionalized pore walls. These results have implications for nanopore sensing platform design.

2007-07-12

199

ESCA-investigations of the passive films formed on austenitic stainless steels in nitric acid  

International Nuclear Information System (INIS)

By means of ESCA the composition and the thickness of passive films formed on austenitic stainless steels were investigated after the attack of nitric acid at various temperatures and acid concentrations. The outermost layers of the oxide film consist of SiO_2, then a layer rich of Cr-oxid follows, containing also some Mo in the four- and sixvalent state. Ni does not contribute to the oxide film. Cr is also enriched in the metal just below the oxide film. (orig.).

1978-01-01

200

Dissociation energies of HfO and ThO  

International Nuclear Information System (INIS)

The RKR potential energy curves are constructed for the ground states of diatomic hafnium oxide and thorium oxide. Using Lippincott and Hulburt-Hirschfelder potential function the dissociation energies are estimated by curve fitting method. The H-H potential function was found to give a better fit in both cases. The dissociation energies of hafnium oxide and thorium oxide are estimated as 9.04 #+-# 0.02 eV and 10.34 #+-# 0.01 eV respectively. (author).

207

AN AES/XPS STUDY OF THE CHEMISTRY OF PALLADIUM ...  

Science.gov (United States)

... AT THE INTERFACE, A THIN OXIDE LAYER IS OBSERVED ALONG WITH POSSIBLE PALLADIUM SILICIDES. PALLADIUM ...

1981-02-01

209

The effect of sodium on the MoO sub 3 -SiO sub 2 -catalyzed partial oxidation of methane  

Energy Technology Data Exchange (ETDEWEB)

The effect of sodium on the partial oxidation of methane over MoO{sub 3}-SiO{sub 2} in the presence of molecular oxygen has been investigated. As in the sodium-free case, the major products are formaldehyde, carbon monoxide, carbon dioxide, and water. Kinetic analysis indicates that methane is directly oxidized to formaldehyde and carbon dioxide. Formaldehyde is oxidized to carbon monoxide, which is itself further oxidized, providing an alternative route to carbon dioxide. The kinetic model shows that sodium poisons the direct oxidation of methane to formaldehyde and carbon dioxide, but promotes the oxidation of formaldehyde and carbon monoxide. Model predictions of rates and selectivities are in good agreement with the experimental data. A mechanism that explains both the poisoning and promotion effects of sodium on MoO{sub 3}-SiO{sub 2} is proposed.

1990-12-01

210

Studies on heterogeneous simulated Am targets. Influence of lanthanide oxides  

Energy Technology Data Exchange (ETDEWEB)

Targets for heterogeneous transmutation of americium are composed of a support material, the inert matrix and of an americium oxide compound: AmO{sub 2-x} or Am{sub 2}O{sub 3}. In parallel to the studies using americium, simulated compounds of americium oxide, chosen amongst lanthanide oxides, are used. The selection of these compounds is based on theoretical, physical and crystallochemical considerations. In order to assess the influence of impurities composed of lanthanide oxides, resulting from the separation process, on the physical and chemical properties of such a target, synthesis of oxide powders containing impurities associated with the simulated americium oxide, characterizations, crystallographic studies and sodium compatibility tests have been performed. (author)

1997-12-31

211

Relationships between Film Chemistry, Structure, and Mechanical Properties in Titanium Oxide  

Energy Technology Data Exchange (ETDEWEB)

Titanium oxides were grown anodically to selected final potentials on grade II polycrystalline titanium under different anodization rates. XPS and RBS results show that the oxide consists of primarily TiO2 with a non-stoichiometric oxide/metal interface, with the slower growth rate associated with a thicker layer at the interface. Characterization using TEM reveals that the structure of the oxide evolves from a primarily amorphous phase to islands of crystallites in an amorphous matrix, to an entirely crystalline phase by increasing the polarization potential. Slower growth rates tend to remain crystalline at higher potentials. The mechanical strength of oxide films extracted from load-depth data by nanoindentation varies dramatically for oxide films grown by different rates at 9.4 V, and to a lesser extent at lower potentials. The variation of film strength is ...

2001-01-01

212

Oxidative desulphurization study of gasoline and kerosene  

British Library Electronic Table of Contents (United Kingdom)

Desulphurization of gasoline and kerosene was carried out using organic and inorganic oxidants. Among the organic oxidants used were hydrogen peroxide in combination with acetic acid, formic acid, benzoic acid and butyric acid, while inorganic oxidants used included potassium permanganate and sodium perchlorate. The oxidation of each petroleum oil was carried out in two steps; the first step consisted of oxidation of the feed at moderate temperature and atmospheric pressure while in the second step, the oxidized mixture was extracted with azeotropic mixture of acetonitrile-water. A maximum desulphurization has occurred with NaClO4 and hydrogen peroxide and acetic acid, which are 68% and 61%, respectively in case of gasoline and 66% and 63%, respectively in case of kerosene oil. The FTIR st...

2010-01-01

213

On synergism in inhibition of liquidphase oxidation of styrene and tetralin by organic phosphites and transition eleement acetylacetonates  

International Nuclear Information System (INIS)

Synergism has been observed during inhibiting initiated oxidation of styrene or tetralin by organic phosphites in the presence of complex compounds of some transition metals. The results are given of non-additive intensification of antioxidative activity of triphenylphosphite (TPP) and tri-(4-methyl-6-tert.-- butyl)-phenyl-phosphite (TMBP) in the process of initiated oxidation of styrene or tetralin with addition of acetylacetonates of cobalt and vanadyl. During styrene oxidation, inhibition of the reaction with chelate complex of vanadyl is weakened considerably when phosphite is added into the reaction system. During tetralin oxidation, postcatalytic (or branched) oxidation is observed only for large concentration of vanadyl complex. Addition of TPP to above complex sharply increases the induction period. When the induction period is completed, oxidation of ...

214

Modelling of the partial oxidation of {alpha}, {beta}-unsaturated aldehydes on Mo-V-oxides based catalysts  

Energy Technology Data Exchange (ETDEWEB)

A kinetic model based on the Mars-van Krevelen mechanism that allows to describe the microkinetics of the heterogeneously catalysed partial oxidation of {alpha}, {beta}-unsaturated aldehydes is presented. This conversion is represented by a network, composed of the oxidation of the {alpha}, {beta}-unsaturated aldehyde towards the {alpha}, {beta}-unsaturated carboxylic acid and the consecutive oxidation of the acid as well as the parallel reaction of the aldehyde to products of deeper oxidation. The reaction steps of aldehyde respectively acid oxidation and catalyst reoxidation have been investigated separately in transient experiments. The combination of steady state and transient experiments has led to an improved understanding of the interaction of the catalyst with the aldehyde and the carboxylic acids as well as to a support of the kinetic model assumptions. (orig.)

1998-12-31

215

Oxidative dimerization of methane over lead-magnesium mixed oxide catalysts  

Energy Technology Data Exchange (ETDEWEB)

Our goal was a process to convert methane to higher hydrocarbons oxidatively, since this circumvents thermodynamic yield limits of a strictly degydrogenative process. Keller and Bhasin converted thermodynamic yield limits of a strictly dehydrogenative process. Keller and Bhasin converted methane to higher hydrocarbons by using metal oxides as oxidants, without co-fed oxygen. They stated that selectivity is necessarily poor if gaseous oxygen is present. Jones and Sofranko have also used reducible metal oxides as oxidants in a group of their parents, but later used some of those materials with continuous O{sub 2} feed without much loss of selectivity. Baerns, Lunsford and Otsuka have shown that high selectivity could be possible with co-fed O{sub 2} at least for low O{sub 2} partial pressures, over PbO-A1{sub 2}O{sub 3}, Li-MgO and rare earths. The performance of a group of ...

1987-08-01

216

Oxidative dehydrodimerization of propylene over a Bi/sub 2/O/sub 3/-La/sub 2/O/sub 3/ oxide ion-conductive catalyst  

Energy Technology Data Exchange (ETDEWEB)

The oxidative dehydrodimerization of propylene to C/sub 3/-dimers (1,5-hexadiene and benzene) has been examined at 600/sup 0/C and atmospheric pressure using a (Bi/sub 2/O/sub 3/)/sub 0.85/(La/sub 2/O/sub 3/)/sub 0.15/ oxide ion-conducting catalyst in a reactor where a catalyst disk separates a feed of propylene in helium from air. The surface of the disk exposed to propylene was reoxidized not by gaseous O/sub 2/, but by the dissociative adsorption and reduction of dioxygen at the oxidant side of the disk, followed by oxide ion conduction to replace spent lattice oxygen. Selectivity to C/sub 3/-dimers when using lattice oxide migration to reoxidize the catalyst was considerably greater than when O/sub 2/ was added to the propylene feed under the same reaction conditions. This result supports the proposal that lattice oxygen is predominantly involved in the selective ...

1986-11-01

217

Electrical properties of inalp native oxides for metal-oxide-semiconductor device applications  

Science.gov (United States)

Data are presented on the insulating properties and capacitance-voltage (CV) characteristics of metal-oxide-semiconductor (MOS) device-thickness (below approx. 100 nm) native oxides formed by wet thermal oxidation of thin InAlP epilayers lattice matched to GaAs. Low leakage current densities of J=1.4 x 10-9 A/cm2 and J=8.7 x 10-11 A/cm2 are observed at an applied field of 1 MV/cm for MOS capacitors fabricated with 17 nm and 48 nm oxides, respectively. TEM images show that the In-rich interfacial particles which exist in 110 nm oxides are absent in 17 nm oxide films. Quasi-static capacitance-voltage measurements of MOS capacitors fabricated on both n-type and p-type GaAs show that the InAlP oxide-GaAs interface is sufficiently free of traps to support inversion, indicating an unpinned Fermi level. These data suggest that InAlP native ...

2004-09-01

218

Alloys and oxides on carbon-supported Pt-Sn electrocatalysts for ethanol oxidation  

Energy Technology Data Exchange (ETDEWEB)

This work reports studies of ethanol oxidation on Pt-Sn/C catalysts with nearly the same particle size and identical overall composition having different amounts of oxide and alloyed phases. Results of characterization of physical properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and in situ dispersive X-ray absorption spectroscopy (DXAS) are presented. The variation in the amount of oxide and alloyed phases, promoted by heat treatments in mild temperature conditions, does not produce any significant particle growth. Cyclic voltammetry and oxidation of adsorbed CO in acid medium are used to probe the surface conditions. Data on the electrocatalytic activity towards ethanol oxidation, obtained by potential sweeps and chronoamperometry, are discussed and correlate well with ...

2010-06-01

219

The benefits of low level radiation  

Energy Technology Data Exchange (ETDEWEB)

The assumed linear relationship between exposure to radiation and cancer incidence is questioned in this article. The current research data on radiation effects at the cellular level is reviewed, as are epidemiological studies of background radiation effects and health effects of populations exposed to low levels of radiation exposure via employment or medical treatments. Statistics reveal that threshold levels currently in force need to be reviewed. Some evidence of beneficial effects of low level radiation exposure effects of low level radiation exposure is also presented, and so regulations should be reviewed at an international level. (UK).

1997-06-01

220

Stimulated radiation of high - current relativistic electron beams  

International Nuclear Information System (INIS)

The most propagated mechanisms of stimulated radiation of electron beam such as Cherenkov one-particle and collective effects, ondulator and magnetic bremsshrahlung radiations, Doppler anomalous effect, Thompson and Raman scattering and radiation are discussed. Relation of spontaneous radiation mechanisms of individual electron and stimulated radiation effects in electron beams has been elucidated, grounds of linear electrodynamics of radiative beam instabilities are stated, and main mechanisms of their nonlinear stabilization are elucidated as well. Various simulated processes in electron beams are considered from the unique point of view using a simple mathematical apparatus and such physical laws as conservation and Newton laws.

1987-01-01

221

Biogenic emissions of isoprenoids and NO in China and comparison to anthropogenic emissions  

International Nuclear Information System (INIS)

In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10 x 10 km) biogenic emissions of isoprene (C_5H_8), monoterpenes (C_1H_1_6), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with season and local time. During winter (January), the biogenic isoprenoid emissions are the lowest, resulting from lower temperature ...

2006-12-01

222

Corrosion resistance of oxide scale formed on SiSiC in boiling sulfuric acid  

International Nuclear Information System (INIS)

SiSiC is one of selected materials for the thermal chemical hydrogen production IS (Iodine-Sulfur) process at JAERI. SiSiC was tested in boiling sulfuric acid for 1000 hours. The obtained results showed the following facts. The transverse strength was not changed by sulfuric corrosion, high temperature oxidation and oxidation. Silica scale formed on SiSiC by sulfate corrosion and high temperature oxidation had corrosion resistance in boiling sulfuric acid. Bilayer structure of silica scale produced by high temperature oxidation was not affected by sulfate corrosion. (S.Y.).

223

Radiation protection. A guide for scientists and physicians  

International Nuclear Information System (INIS)

This manual was written for individuals who wish to become qualified in radiation protection as an adjunct to working with sources of ionizing radiation or using radionuclides in the field of medicine. It provides the radiation user with information needed to protect himself and others and to understand and comply with governmental and institutional regulations regarding the use of radionuclides and radiation machines. It is designed for a wide spectrum of users, including physicians, research scientists, engineers, and technicians. It should be useful also to radiation safety officers, members of radiation safety committees, and others who are responsible for the proper use of radiation sources, although they may not be working with the sources directly. The presentation in this manual is designed to obviate the need for reviews of atomic ...

224

Combining satellite data and models to estimate cloud radiative effect at the surface and in the atmosphere  

British Library Electronic Table of Contents (United Kingdom)

Abstract Satellite measurements and numerical forecast model reanalysis data are used to compute an updated estimate of the cloud radiative effect on the global multi-annual mean radiative energy budget of the atmosphere and surface. The cloud radiative cooling effect through reflection of short wave radiation dominates over the long wave heating effect, resulting in a net cooling of the climate system of - 21 Wm-2. The short wave radiative effect of cloud is primarily manifest as a reduction in the solar radiation absorbed at the surface of - 53 Wm-2. Clouds impact long wave radiation by heating the moist tropical atmosphere (up to around 40 Wm-2 for global annual means) while enhancing the radiative cooling of the atmosphere over other regions, in particular higher latitudes and sub-trop...

2011-01-01

225

Biological effects of electromagnetic radiation in the microwave range  

Energy Technology Data Exchange (ETDEWEB)

The book examines current experimental and clinical knowledge concerning the biological and biophysical effects of electromagnetic radiation, particularly that in the microwave range. The biophysical bases of the interaction of electromagnetic radiation with matter are reviewed with emphasis on biological systems, and the effects of radiation on critical biological systems, including the nervous, reproductive, visual and blood-forming systems are compared. Data concerning the lethal effects of nonionizing radiation is presented and characteristics of the effects of electromagnetic radiation on the whole mammalian organisms are examined. Various reactions of the neuroendocrine system to electromagnetic radiation are described, with particular attention given to the adrenal system, and the combined effects of ionizing and microwave radiation ...

1980-01-01

226

[The indicators of biological age and accelerated aging in liquidators of the consequences of radiation emergency].  

Science.gov (United States)

The biological age (BA) of the majority of the liquidators of the consequences of the radiation accidents in the Navy and of the liquidators of the Chernobyl' APS accident exceeds the medium standard and the DBA (due BA). The index of the BA can be a characteristic of the influence of the social-hygienic factors on the health condition of the Special Risk Subunit--the liquidators of the consequences of the radiation accidents. It was established, that the radiation influence concerns to the factors dramatically increasing the BA and the rate of senescence of the liquidators of the consequences of the radiation accidents. PMID:21809627

2011-01-01

227

The THz Radiation from Undulator  

Science.gov (United States)

The experimental device for generation of undulator radiation in terahertz wavelength region by use of undulator with ferromagnets is created. The device is based on a beam of a microtron with the energy 7.5 MeV. The radiation wavelength is 200 mu. Registered spontaneous radiation has a power 10{sup -6} W at a current of a beam 2 mA in a pulse. With the optical resonator, in a mode, the amplification of 6% is received, that in sometimes is more than the expected value. This effect is explained as a result of partial coherence of radiation.

2010-02-03

228

Study of emission of Cerenkov radiation by tachyons  

Energy Technology Data Exchange (ETDEWEB)

The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation.

1983-01-01

229

Radiation facility with electron accelerator of the Institute for Nuclear Research of Ukraine, Kiev  

International Nuclear Information System (INIS)

Characteristics of the Ukrainian NSA NRI radiation facility for scientific researches and developments of industrial radiation technology are performed. Parts of the facility, design peculiarities of technical tools are described. Biological protection of the facility and radiation protection system, transport line, systems of technical provision and radiation measurements are discussed

2003-02-01

230

Radiation exposure of the population of the GDR by X-ray diagnostics  

International Nuclear Information System (INIS)

The radiation burden of the people of the GDR in relation to biomedical radiography altogether as well as organ doses, gonad doses and genetically significant doses in detail are outlined. The concepts of radiation protection and standards of radiographic examination are demonstrated. Possibilities of influencing radiation exposure by scientifically based indication of X-ray examination, application of new and improvement of usual examination techniques are discussed with regard to quality assurance and control. Proposals concerning the reduction of radiation exposure of the GDR population are presented.

1986-01-01

231

Potential Hazards from Neutrino Radiation at Muon Colliders  

CERN Document Server

High energy muon colliders, such as the TeV-scale conceptual designs now being considered, are found to produce enough high energy neutrinos to constitute a potentially serious off-site radiation hazard in the neighbourhood of the accelerator site. A general characterization of this radiation hazard is given, followed by an order-of-magnitude calculation for the off-site annual radiation dose and a discussion of accelerator design and site selection strategies to minimize the radiation hazard.

1999-01-01

232

Model of quantum noise of shadow radiation images  

International Nuclear Information System (INIS)

Correlation characteristics of quantum noise on the shadow radiation image (RI) of the object under nondestructive testing are studied. Mathematical model of RI occasional distortions is derived. The model takes into account the parameters of object under testing and of radiation beam by radiation quanta flux density. The results obtained can be used as a component in the process of investigation of various radiation testing systems

233

Coherent oscillator radiation  

International Nuclear Information System (INIS)

Coherent oscillator radiation is considered. A comparison is made with classical particle radiation with gauss distribution. Decay probability for coherent state in spontaneous radiation is estimated. The method suggested for describing harmonic oscillator allows to separate the effect of classical field radiation from quantum description of particle state within the framework of a self-consistent quantum mechanical problem.

1982-04-01

234

Studies on reactivity of coal surfaces at low temperature; Teion ni okeru sekitan hyomen no hannosei no kento  

Energy Technology Data Exchange (ETDEWEB)

With an objective to learn reactivity of coal at its surface, surfaces of oxidized coal samples were investigated. Miike coal was oxidized by using {sup 18}O2 in a closed loop system. As the reaction progresses, proportion of CO2 including isotopes increased rapidly as a result of oxidation of CO sites existing in the coal and the newly generated C{sup 18}O sites. The oxidizing reaction progressed via oxygen adsorbing sites generated near the surface, and oxygen containing groups. An FT-IR analysis estimated the depth of the oxidized layer to be 10{mu}m or less from particle surface. The oxidized coal was pulverized to see its surface condition. Functional groups introduced by the oxidation enter into the vicinity of the surface in a form to desorb as CO. CO2 is trapped in inner pores. The coal surface was observed by using an atomic force ...

1996-10-28

235

Physical characterization of a new composition of oxidized zirconium-2.5wt% niobium produced using a two step process for biomedical applications  

British Library Electronic Table of Contents (United Kingdom)

Zirconium and particularly Zr-2.5wt%Nb (Zr2.5Nb) alloy are useful for engineering bearing applications because they can be oxidized in air to form a hard surface ceramic. Oxidized zirconium (OxZr) due to its abrasion resistant ceramic surface and biocompatible substrate alloy has been used as a bearing surface in total joint arthroplasty for several years. OxZr is characterized by hard zirconium oxide (oxide) formed on Zr2.5Nb using one step thermal oxidation carried out in air. Because the oxide is only at the surface, the bulk material behaves like a metal, with high toughness. The oxide, furthermore, exhibits high adhesion to the substrate because of an oxygen-rich diffusion hardened zone (DHZ) interposing between the oxide and the substrate. In this study, we demonstrate a two step pro...

2011-01-01

236

Measurement of oxidation rate of sulfite in rain water in Yokohama, Japan  

Energy Technology Data Exchange (ETDEWEB)

In recent years, the influences of acid rain such as the acidification of lake water, on bio-system by the heavy metals from effluent of soils with acid rain and also on the structural materials of buildings are seriously discussed. Sulfur and nitrogen that are contained in fossil fuels are released into the atmosphere by the fuel combustion as their oxides dissolve in rain drops as sulfite and nitrous ions, where they are further oxidized into sulfate and nitrate ions These ions lower the pH of rain water resulting so-called acid rain. Therefore, it is important to accurately determine these ions in rain water for the investigation of reality of acid rain. However, it is not easy to accurately determine these ions, especially for sulfite ions in rain water, since they are quickly oxidized by the catalytic action of metallic ions such as ferric and manganous ions. And light, temperature, pH of solution and also species and ...

1986-04-01

237

Study of Pd-Sn/Al{sub 2}O{sub 3} catalysts prepared by an oxide colloidal route; Etude de catalyseurs Pd-Sn/Al{sub 2}O{sub 3} prepares par voie colloidale oxyde  

Energy Technology Data Exchange (ETDEWEB)

The oxide colloidal route, developed in the laboratory for mono-metallic catalysts, consists in preparing a metallic oxide hydro-sol which leads to the supported catalyst after deposition onto a support and an activation stage. In this work, this method has been adapted to the preparation of alumina supported bimetallic Pd-Sn catalysts to determine its interest for the control of the properties of the bimetallic phase (size, composition and structure). In the preliminary study concerning tin oxide sols, SnO{sub 2} (size=2,3 nm) and Sn{sub 6}O{sub 4}(OH){sub 4} (size = 25 nm) nano-particles were synthesized by neutralization respectively for tin(IV) and tin(H). The control through the pH of the aggregation of the PdO and SnO{sub 2} particles revealed that increasing oxide solubility promotes integral re-dispersion of the oxide particles. To synthesize oxide ...

2001-09-01

238

The properties and transport phenomena in oxide films on iron, nickel, chromium and their alloys in aqueous environments  

International Nuclear Information System (INIS)

The construction materials used in coolant systems in nuclear power plants become covered with oxide films as a result of exposure to the aqueous environment. The susceptibility of the materials to different forms of corrosion, as well as the extent of the incorporation of radioactive species on the surfaces of the primary circuit, are greatly influenced by the physical and chemical properties of these oxide films. The composition and characteristics of the oxide films in turn depend on the applied water chemistry. This work was undertaken in order to collect and evaluate the present views on the structure and behaviour of oxide films formed on iron- and nickel-based materials in aqueous environments. This survey should serve to recognise the areas in which more understanding and research effort is needed. The review begins with a discussion on the bulk oxides of iron, nickel and ...

2010-03-01

239

A kinetic and mechanistic study of the oxidation of silicon- and thin metal silicide layers  

International Nuclear Information System (INIS)

The formation of thin SiO_2 layers on silicon and metal silicides was studied by phase- and thickness measurements with Rutherford back-scattering of 2 MeV alfa particles. Thermal oxidation was done in steam and dry oxygen at temperatures between 750 degrees Celsius and 1 100 degrees Celsius, while SiO_2 formation at room temperature was carried out by anodic oxidation. The study of silicon oxidation was done on Si<100>, Si<111> and amorphous silicon substrates. Thermal oxidation of CoSi_2, CrSi_2, NiSi_2, PtSi and TiSi_2 was investigated. The oxidation rates of the silicides were found to be much higher than for silicon. The oxidation process is also diffusion-limited with a higher oxidation rate for steam as compared to dry oxygen. The silicide layers were found to stay intact during thermal oxidation. A ...

240

Technology of iodine-131 production and its application  

International Nuclear Information System (INIS)

Full text: Production: This radio iodine produced by three methods: 1) Wet method: The irradiated tellurium is dissolved in an oxidizing mixture which also converts iodine in to iodide. This is a chemical method and iodine that it produced with this method has low purity and efficiency. 2). Dry Method: The irradiated tellurium is dissolved in furnace (750 deg. C) with sublimation method and iodine absorbed in sodium solution . In this case we have more than 99.5 % purity and 80 % efficiency. We are using this type in Iran. 3) Fission fragment method: In this case the iodine separated from fission fragment directly and we have high purity (career free) and specific activity of iodine. Application: Iodine is a versatile tracer element. It is used to determine thyroid cancer metastases, and size, shape and activity of the thyroid gland. Critical organ of iodine is thyroid gland. One of the common diagnostic procedures for determining thyroid function therefore, is to ...

241

Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin  

International Nuclear Information System (INIS)

The 177 underground storage tanks at the DOE's Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. CS-100 shows the presence of phenoxy-ether ...

2004-09-10

242

Survey of degradation modes of candidate materials for high-level radioactive-waste disposal containers  

International Nuclear Information System (INIS)

Three copper-based alloys, CDA 102 (oxygen-free, high-purity copper), CDA 613 (aluminum bronze), and CDA 715 (Cu-30Ni), are candidates for the fabrication of high-level radioactive-waste disposal containers. Waste will include spent fuel assemblies from reactors as well as borosilicate glass, and will be sent to the prospective repository site at Yucca Mountain in Nye County, Nevada. The decay of radionuclides will result in the generation of substantial heat and in fluxes of gamma radiation outside the containers. In this environment, container materials might degrade by atmospheric oxidation, general aqueous phase corrosion, localized corrosion (LC), and stress corrosion cracking (SCC). This volume is a critical survey of available data on pitting and crevice corrosion of the copper-based candidates. Pitting and crevice corrosion are two of the most common forms of LC of these materials. Data on the SCC of these alloys is surveyed in Volume ...

1991-07-01

243

Search for the active components and studies on the mechanism of the hematopoiesis improvement foods  

Energy Technology Data Exchange (ETDEWEB)

In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation of macrophage cell line with herval extracts with the treatments of recombinant interferon-{gamma} resulted in increased nitric oxide synthesis in a dose-dependent manners. In addition, ...

1999-04-01

244

Relationship of DNA repair processes to mutagenesis and carcinogenesis in mammalian cells. Progress report, November 1, 1979-October 31, 1980  

International Nuclear Information System (INIS)

The objective of this research is to determine the role of DNA repair in mutagenesis and carcinogenesis in mammalian cells. Use of the host-cell reactivation viral suicide enrichment procedure was initiated in the isolation of repair-deficient mutants. Lightly mutagenized BHK cells were infected with irradiated Herpes simplex virus (HSV); several radiation-sensitive strains were isolated among the survivors of the infection. The characterization of these strains is progressing and the enrichments are continuing. That alterations in the frequency of mutation of C3H/10T 1/2 cells, occurring as a result of holding the cells in a confluent state following treatment with ethylmethane sulfonate, parallel the alterations in the frequency of neoplastic transformation was found. The repair capabilities of BHK cells were found to be intermediate in comparison to repair-proficient and -deficient human cells with regard to the reactivation of HSV treated with various ...

245

Influence of irradiation spectrum and implanted ions on the amorphization of ceramics  

Energy Technology Data Exchange (ETDEWEB)

Polycrystalline Al2O3, magnesium aluminate spinel (MgAl2O4), MgO, Si3N4, and SiC were irradiated with various ions at 200-450 K, and microstructures were examined following irradiation using cross-section TEM. Amorphization was not observed in any of the irradiated oxide ceramics, despsite damage energy densities up to {similar_to}7 keV/atom (70 displacements per atom). On the other hand, SiC readily amorphized after damage levels of {similar_to}0.4 dpa at room temperature (RT). Si3N4 exhibited intermediate behavior; irradiation with Fe{sup 2+} ions at RT produced amorphization in the implanted ion region after damage levels of {similar_to}1 dpa. However, irradiated regions outside the implanted ion region did not amorphize even after damage levels > 5 dpa. The amorphous layer in the Fe-implanted region of Si3N4 did not appear if the specimen was simultaneoulsy irradiated with 1-MeV He{sup +} ions at RT. By comparison with published results, it is concluded that ...

1995-12-31

246

Ellipsometric and spectral measurements in the study of chemically coloured 304 stainless steel selective surfaces  

Energy Technology Data Exchange (ETDEWEB)

Ellipsometric studies and reflectance measurements on five anodized coloured 304 stainless steel samples (Brown, Violet, Blue, Light Grey and Dark Grey) are reported. The optical properties, solar absorptance and thermal emittance of samples have been obtained. Measured values of absorptance lay between 0.75-0.87 together with a near normal emittance value approx. =0.10 at 100/sup 0/C. The total hemispherical emittance has been measured at 100 and 200/sup 0/C for the sample having the best selective surface. This study shows that the blue coloured surface has the most favourable combination of radiation properties. The surface deteriorates at temperatures above 210/sup 0/C. Oxidation is assumed to be the deterioration mechanism. The different samples exhibited difference in the /PSI/ and ..delta.. parameters as determined by ellipsometry both before and after heat treatments. When brown and violet samples were coated with a 125 nm layer of ...

1982-09-01

247

Characterization and Source Term Assessments of Radioactive Particles from Marshall Islands Using Non-Destructive Analytical Techniques  

Energy Technology Data Exchange (ETDEWEB)

A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and {sup 241}Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and ...

2005-06-11

248

Bitumen immobilization of aqueous radwaste by thin-film evaporation  

International Nuclear Information System (INIS)

In the early 1980s, AECL built a Waste Treatment Centre (WTC) for managing low-level solid and aqueous liquid wastes for converting CANDU wastes. At present, two liquid waste streams are being treated at the WTC. The liquid waste streams are volume-reduced by a combination of continuous crossflow microfiltration (MF), spiral wound reverse osmosis (SWRO) and tubular reverse osmosis (TRO) membrane technologies. The concentrate produced from the TRO system and the volume-reduced MF backwash solutions are evaporated while simultaneously adding bitumen in a thin-film evaporator. A water-free product of chemical and radiochemical salts and bitumen is removed in 200-L galvanized steel drums for storage. The radiation field of product drums on contact typically has a value of 0.5 to 3 R/h depending upon the feed concentration of radioactivity to the evaporator. The total solids content in the 200-L drum ranges from 25 to 35%. Encapsulated in the bitumen matrix are a ...

1996-02-25

249

Study of particles trapped by a magnetic field  

Science.gov (United States)

A new type of radiation which occurs when particles are accelerated in the field of a longitudinal wave and in a transverse magnetic field is studied. The characteristics of such spontaneous radiation are obtained, and the influence of collective effects on the radiation is analyzed. The application of the findings to the theory of free electron lasers is discussed. 8 references.

1986-01-01

251

Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries  

UK PubMed Central (United Kingdom)

Objectives To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental,...Full Text Available

2005-07-09

252

Radiation therapy alone versus radiation therapy and chemotherapy in the management of Hodgkin's disease.  

UK PubMed Central (United Kingdom)

Forty-four patients with histologically proven Hodgkin's disease underwent initial treatment with extended-field radiation therapy. Nineteen of these patients also received combination chemotherapy....Full Text Available

1990-02-01

253

Radiation exposure due to X-rays of the hip joint in babies  

International Nuclear Information System (INIS)

Exact anatomic knowledge about the location of the gonads and the application of corresponding measures of radiation protection are the preconditions for an efficient reduction of the danger of a possible genetic damage as a result of radiation exposition during X-ray examination of the hip joint of newborns. (VJ).

254

Multiscale registration of planning CT and daily cone beam CT images for adaptive radiation therapy  

UK PubMed Central (United Kingdom)

Adaptive radiation therapy (ART) is the incorporation of daily images in the radiotherapy treatment process so that the treatment plan can be evaluated and modified to maximize the amount of radiation...Full Text Available

2009-01-01

255

Lagranzheva dinamika kollektivnykh vzaimodejstvij v potokakh diskretnykh izluchatelej. (Lagrange dynamics of collective interactions in flows of discrete radiators).  

Science.gov (United States)

Analytical method of theoretical simulation of collective hydrodynamic instabilities of intensive flows of discrete radiators, interacting with each other only through the coherent fields of their spontaneous radiation in corresponding media was suggested...

1989-01-01

256

Granite Countertops and Radiation | Radiation Protection | US EPA  

Wastenet

... Top of page Testing Radiation coming from granite countertops results from natural radioactive material in the granite. Identifying the presence and concentration of radioactive elements in granite requires expensive and sophisticated portable instruments or laboratory equipment. These instruments and equipment require proper calibration, and interpretation of ...

257

Are natural radioactive materials dangerous  

International Nuclear Information System (INIS)

The different radiation loads caused by natural and artificial radionuclides are compared in this paper. This examples will serve to illustrate that the problem of population exposure to radiation can only be solved in consideration of all components and to show which effects of the radiation from natural sources are of special importance in this connexion. (orig./AK).

1974-09-23

258

A radiator of electromagnetic waves with a combined shape of generatrices  

British Library Electronic Table of Contents (United Kingdom)

The problem of optimizing a horn radiator of electromagnetic waves for the reflection coefficient and the coefficient of transformation of the fundamental mode into higher order modes is solved. Optimization is performed by means of selecting a combined shape of the radiator generatrices.

2008-01-01

259

Morphological development of surface scales during long term oxidation of a low Al-substituted #beta#'-sialon  

International Nuclear Information System (INIS)

The morphological development of oxide scales formed on a low Al substituted #beta#-sialon (z=0.2) oxidised for time periods up to 1024h at 1350 C is discussed in relation to oxidation kinetics. The oxidation process is observed to be accompanied by changes in both the phase assemblage of the external layers and their morphology. Thus as the time of oxidation increases beyond 64h the cristobalite-#beta#-yttrium disilicate phase assemblage changes to cristobalite plus #beta#- and #gamma#-yttrium disilicate. In addition to the changes observed for the surface layers, differences are observed in the morphologies of the polished cross-sections. These changes are consistent with an order of magnitude decrease in oxidation rate. (orig.).

1993-10-04

260

Manufacturing of oxide-dispersion-strengthened steels with the use of preliminary surface oxidation  

British Library Electronic Table of Contents (United Kingdom)

Regularities of deformation-induced dissolution of a surface layer of iron oxides in matrixes of iron-based alloys with bcc and fcc lattices have been studied by the methods of M?ssbauer spectroscopy, transmission electron microscopy, and X-ray diffraction. A method of producing iron alloys strengthened by dispersed oxide nanoparticles and alloyed with elements possessing a high affinity to oxygen (titanium and yttrium) has been proposed, which implies a dynamic dissolution of a surface layer of iron oxides upon strong cold deformation and a precipitation of secondary yttrium and titanium nanooxides upon a subsequent high-temperature sintering of mechanically alloyed powders. There has been demonstrated a possibility of oxide strengthening of pure iron upon its interaction with air without...

2011-01-01

261

Degradation of gas turbine coatings and life assessment  

Energy Technology Data Exchange (ETDEWEB)

MCrAlY coatings are widely used on hot section components of gas turbines to provide hot corrosion and/or oxidation protection by formation of an oxide layer on the surface. As the protective oxide scale exfoliates during service, aluminum from the coating diffuses outward for reformation of the protective scale. Aluminum may also diffuse inward due to the differences in composition between the coating and the substrate. Thus, the coatings degrade due to oxidation, oxide scale spallation, and inward and outward diffusion of aluminum. Service life of these coatings is controlled by the aluminum content in the coating, operating temperature and start- shutdown cycles. In-service degradation of CoCrAlY and CoNiCrAlY coatings is presented. A procedure to predict the remaining service life of coatings under oxidizing conditions is discussed. (orig.) 12 refs.

1998-12-31

262

Using ICCD as a fast optical switch to measure harmonic super-radiation from an optical klystron in a storage ring  

International Nuclear Information System (INIS)

An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate

2001-07-01

263

The medical exposures to ionizing radiations, it is a world priority in radiation protection  

International Nuclear Information System (INIS)

The document published under A/63:46 and titled report of the scientific committee of United Nations for the study of ionizing radiations effects, gives the situation of the fifty sixth session of the committee that stood at Vienna from the 10. to 18. july 2008. In the chapter 3 of this report the writers summarize the strategic planning and the working program of the scientific committee for the period 2009-2013. They note that the committee worry about the inadequate means, particularly in personnel. The priorities for the given period will be the medical exposure of patients, the radiation levels and the effects of energy production, the exposure to natural radiation sources and the improvement of the understanding of the effects of the low doses radiation exposure. (N.C.)

264

x - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011 ... Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation ...

265

VOLUME I11 IMISSION SYSTEM PERFORMANCE - NASA Technical Report ...  

Science.gov (United States)

Nov 8, 2010 ... Ihring Mission 11, the radiation dosimetry measurement system functioned normally and provided data on the Earth's trapped radiation belts ...

266

Treatment of persons exposed in radiation accidents or nuclear explosions. Omhaendertagande av skadade vid radiakolyckor och kaernvapenexplosioner  

Energy Technology Data Exchange (ETDEWEB)

The report gives general principles of treatment and care of casualties caused by radiation accidents or nuclear explosions.

1991-01-01

267

The importance of radiation quality for optimisation in radiology  

UK PubMed Central (United Kingdom)

Selection of the appropriate radiation quality is an important aspect of optimisation for every clinical imaging task in radiology, since it affects both image quality and patient dose. Spreadsheet...Full Text Available

269

Tachyon Cerenkov radiation  

Energy Technology Data Exchange (ETDEWEB)

By proposing the four-dimensional, reciprocity transformations the appropriate condition for superluminal electromagnetic Cerenkov radiation is obtained by introducing the hypothesis that tachyons possess vector energy and scalar momentum.

1985-09-01

270

Solar Cell Radiation Response near the Interface of Different ...  

Science.gov (United States)

... Solar Cell Radiation Respinnse Near the Interface o~f fliffprerv- ... 5 4. CALCUTl-ATED SOLAR CELL RLSPONSE FOR VARIOUS BASE MATERIALS ...

1971-11-01

271

Relationship of Optical Coating on Thermal Radiation ...  

Science.gov (United States)

drical Enclosures Using a Numerical Ray Tracing Technique. NASA. TM-I02527, 1990 . Buckley, H.: Radiation from the Interior of a Reflecting Cylinder. Philos. ...

272

References | Radiation Protection | US EPA  

Wastenet

...References | Radiation Protection | US EPA This page provides links to the reference material on EPA's Radiation Protection Web site. U.S. EPA/...OAR/ORIA/Radiation Protection Division Jump to main content. Radiation Protection Contact Us Search: All EPA This Area You are here: EPA Home ... Radiation Protection References PageName Technical Users General Public Reporters Librarians Students/Teachers PROGRAMS TOPICS REFERENCES References The Reference Section provides general material that support the ...other sections of EPA's Radiation Protection Web site. You will find links within the information to related pages throughout the Radiation Protection , EPA ...

273
274

Radiation deamination of tetracycline. [Gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

The fundamental product of tetracycline hydrochlorine gamma radiolysis was separated in its solid state. From the results of spectroscopic studies it has been established that it is des-N,N-dimethylaminotetracycline.

1980-01-01

275

Radiation Damage Calculations for the FUBR and BEATRIX Irradiations of Lithium Compounds in EBR-II and FFTF  

Energy Technology Data Exchange (ETDEWEB)

Radiation Damage Calculations for the FUBR and BEATRIX Irradiations of Lithium Compunds in EBR-II and FFTF

1999-05-01

276

Onclas U9800 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

the probability of its spontaneous radiation de-excitation increases. ... consider spontaneous radiation transitions. We will examine the ...

277

Numerical analysis of methane-air combustion considering radiation effect  

Energy Technology Data Exchange (ETDEWEB)

Turbulent premixed methane-air combustion in a cylindrical chamber is numerically simulated considering radiation effect. Reaction rates are considered as minimum rates between Arrhenius rates and eddy break up rates. A five step reduced mechanism is used. Turbulent modeling is done via standard k-{epsilon} model imposed by empirical inlet boundary conditions. Source terms of energy equation consist of reaction rates and radiation effects. The discrete ordinate method (DOM) is employed to solve the radiative transfer equation (RTE) and the weighted sum of gray gas model (WSGGM) is imposed to consider radiation effect of non-gray gases. The results indicate that in the case of turbulent combusting flows, the effect of radiation of gases can affect the temperature and species concentrations. The numerical results obtained considering radiation effect are closer to ...

2008-12-15

278

Numerical analysis of methane-air combustion considering radiation effect  

International Nuclear Information System (INIS)

Turbulent premixed methane-air combustion in a cylindrical chamber is numerically simulated considering radiation effect. Reaction rates are considered as minimum rates between Arrhenius rates and eddy break up rates. A five step reduced mechanism is used. Turbulent modeling is done via standard k-? model imposed by empirical inlet boundary conditions. Source terms of energy equation consist of reaction rates and radiation effects. The discrete ordinate method (DOM) is employed to solve the radiative transfer equation (RTE) and the weighted sum of gray gas model (WSGGM) is imposed to consider radiation effect of non-gray gases. The results indicate that in the case of turbulent combusting flows, the effect of radiation of gases can affect the temperature and species concentrations. The numerical results obtained considering radiation effect are closer to the ...

2008-12-01

279

Multifunctional, Boron-Foam Based Radiation Shielding  

Science.gov (United States)

PROPOSAL NUMBER: 04 B3.09-7744. SUBTOPIC TITLE: Radiation Shielding to Protect Humans. PROPOSAL TITLE: Multifunctional, Boron-Foam Based ...

280

Mathematical Analysis of Three Free-Electron-Laser Issues  

Science.gov (United States)

... iFfficiency-en- enhanced spontaneous radiation at the free-electron- ... as enhanced spontaneous radiation at the free-electron-laser wavelength. ...

1990-09-30

281

Equipment hardening and hardness assurance  

International Nuclear Information System (INIS)

The introduction of tolerance to radiation (''radiation-hardness'') into large electronic systems is one of the major tasks to which this Handbook will be put. The practices recommended here for inculcating radiation-tolerance in equipment require advanced physical modeling techniques, precise engineering procedures, and firm assurance procedures. The degree to which these procedures should be used in an equipment project can be measured by the severity of the raw radiation environment, the desired reliability of the system, and the requirement of that project for radiation-sensitive technologies. The balance of device/circuit design versus shielding will depend on whether the radiation is highly penetrating -- as in isotope handling or military environments -- or readily attenuated, as in space. In this chapter the authors have attempted to summarize the ...

282

Enhanced coherent undulator radiation from bunched electron beams  

International Nuclear Information System (INIS)

When energetic bunches of electrons traverse an undulator field, they can spontaneously emit radiation both coherently and incoherently. Although it has generally been assumed that undulator radiation is incoherent at wavelengths short compared to the longitudinal size of the electron bunch, several recent observations have proved this assumption false. Furthermore, the appearance of coherent radiation is often accompanied by a significant increase in radiated power. Here we report observations of strongly enhanced coherent spontaneous radiation together with direct measurements, using transition radiation techniques, of the electron distributions responsible for the coherent emission. We also report demonstrated enhancements in the predicted spontaneous radiated power by as much as 6x10"4 using electron bunch compression. copyright 1996 ...

1995-09-28

284

ESR study in radiation damage in pyrimidines. 3-year comprehensive progress report  

International Nuclear Information System (INIS)

General mechanisms of radiation damage to biomolecules was studied by using substituted pyrimidines, particularly barbituric acid derivatives.

285

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy  

CERN Document Server

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy

1990-01-01

286

Combined Radiation and Thermal Injury after Nuclear Attack  

Science.gov (United States)

... Except for isolated radiation accidents over the ensuing years, little practical experience has been gained in the treatment of thermal injuries ...

2011-05-13

287

Chinese Journal of Lasers (Selected Articles)  

Science.gov (United States)

... spontaneous radiation of amplifiers within a relatively w~de range of ... pulse widths are 20-30ns, while amplified spontaneous radiation pulse ...

1991-12-10

288

An evaluation of planning techniques for stereotactic body radiation therapy in lung tumors  

UK PubMed Central (United Kingdom)

PurposeTo evaluate four planning techniques for stereotactic body radiation therapy (SBRT) in lung tumors.Methods...Full Text Available

2008-04-01

289

Yttrium Oxides in Vacuum-Plasma-Sprayed CoNiCrAlY ...  

Science.gov (United States)

... Accession Number : ADD141533. Title : Yttrium Oxides in Vacuum-Plasma- Sprayed CoNiCrAlY Coatings,. Descriptive Note : Journal Article,. ...

1989-06-01

290

Uranium oxides. Specific surface measurement by nitrogen adsorption  

International Nuclear Information System (INIS)

Determination of the specific surface of uranium oxides: UO_2 and U_3O_8 using a simplified equation derived from the Brunauer, Emmett and Teller theory. The method is suitable for samples having a surface between 6 to 50 m"2.

291

Updated general technical guidelines for the environmentally sound management of wastes consisting of, containing or contaminated with persistent org  

Wastenet

Emissions and residues: Emissions may include, inter alia, nitrogen oxides, carbon monoxide, sulphur dioxide and other oxides

292

The role of metallothionein IIa in defending lens epithelial cells against cadmium and TBHP induced oxidative stress  

UK PubMed Central (United Kingdom)

PurposeHeavy metals and other forms of oxidative stress have been implicated as key factors in the formation of age-related cataract in humans. Metallothioneins are...Full Text Available

293

The oxidative stress theory of aging: embattled or invincible? Insights from non-traditional model organisms  

UK PubMed Central (United Kingdom)

Reactive oxygen species (ROS), inevitable byproducts of aerobic metabolism, are known to cause oxidative damage to cells and molecules. This, in turn, is widely accepted as a pivotal determinant of...Full Text Available

2008-09-01

294

The long lifespan of two bat species is correlated with resistance to protein oxidation and enhanced protein homeostasis  

UK PubMed Central (United Kingdom)

Altered structure, and hence function, of cellular macromolecules caused by oxidation can contribute to loss of physiological function with age. Here, we tested whether the lifespan of bats, which generally...Full Text Available

2009-07-01

295

The effect of nonstoichiometry of surface oxides formed during high temperature oxidation on the corrosion resistance of ferritic chromium steel  

Energy Technology Data Exchange (ETDEWEB)

The influence of surface oxides of variable composition and nonstoichiometry formed at high temperatures in air on the general corrosion resistance of ferritic chromium steel type 08H17T (Fe-17Cr-1Ti) in weak sulfuric acid has been studied. Anodic passive films formed on steel with different pretreatments have also been examined. The surface oxide of nearly stoichiometric composition formed at 300 C provides for the passive state of steel in sulfuric acid despite its depletion by chromium when compared with that for nonstoichiometric Cr-enriched oxide formed at 600 C. The dissolution and transformation of nonstoichiometric thermal surface oxide in sulfuric acid appear to take place through defect sites, {minus}Fe{sup 2+} ions, and oxygen vacancies of the n-type conductor. The passive film formed on the nonstoichiometric oxide film, which had been produced at 600 C, was found to be ...

1998-07-01

296

The Release of Nitric Oxide from S-Nitrosothiols Promotes Angiogenesis  

UK PubMed Central (United Kingdom)

BackgroundFree nitric oxide (NO) reacts with sulphydryl residues to form S-nitrosothiols, which act as NO reservoirs. We sought to determine whether thiol-preserving...Full Text Available

297

The Oxidation Behavior of CoCrAlY, CoCrAl and Yttrium ...  

Science.gov (United States)

... ADD137758. Title : The Oxidation Behavior of CoCrAlY, CoCrAl and Yttrium-Implanted CoCrAl Alloys Compared and Contrasted,. ...

1987-11-01

298

Synthesis and characterization of PVP-coated large core iron oxide nanoparticles as an MRI contrast agent  

UK PubMed Central (United Kingdom)

The purpose of this study was to synthesize biocompatible polyvinylpyrrolidone (PVP)-coated iron oxide (PVP-IO) nanoparticles and to evaluate their efficacy as a magnetic resonance imaging (MRI)...Full Text Available

2008-04-01

299

Sulfur dioxide oxidation catalyst and process  

Energy Technology Data Exchange (ETDEWEB)

A catalytic process for the oxidation of sulfur-containing gases , E.G., sulfur dioxide and simultaneous production of sulfuric acid wherein a sulfur-containing gas is reacted with an oxygencontaining gas in the presence of a catalyst comprising an iron group metal on a solid support comprising a zeolite in a silicaalumina matrix.

1981-01-13

300

Submicromolar concentrations of 4-hydroxynonenal induce glutamate cysteine ligase expression in HBE1 cells  

UK PubMed Central (United Kingdom)

4-Hydroxynonenal (HNE), a major electrophilic product of lipid peroxidation, is regarded as both a marker of oxidative stress and a mediator of oxidative damage. At subtoxic concentrations,...Full Text Available

2007-01-01

301

Rheological Characterization of in situ Crosslinkable Hydrogels Formulated from Oxidized Dextran and N-Carboxyethyl Chitosan  

UK PubMed Central (United Kingdom)

The gelation kinetics of an in situ gelable hydrogel formulated from oxidized dextran (Odex) and N-carboxyethyl chitosan (CEC) were investigated rheologically. Both Schiff base...Full Text Available

2007-04-01

302

Revised model of thermally stimulated current in MOS capacitors  

Energy Technology Data Exchange (ETDEWEB)

It is shown analytically and experimentally that thermally stimulated current (TSC) measurements at negative bias incompletely describe oxide-trap charge in SIMOX and bipolar base oxides irradiated at 0 V. Positive-bias TSC is also required.

1997-06-01

303

Properties of cellulose solutions in methylmorpholine N-oxide containing montmorillonite nanoparticles and of composite films thereof  

British Library Electronic Table of Contents (United Kingdom)

Rheological properties of moderately concentrated solutions of cellulose in methylmorpholine N-oxide-dimethylformamide mixtures containing hydrophilic montmorillonite nanoparticles were studied. Film composite materials were prepared, and their physicomechanical properties and structural organization were studied.

2011-01-01

304

Oxidation of phosphine by iron(III) chloride complexes supported on activated charcoal  

Energy Technology Data Exchange (ETDEWEB)

It has been discovered that iron(III) chloride complexes supported on activated charcoal oxidize phosphine under normal conditions. The process accelerates as the concentration of the chloride ions and the proton acid increases.

1988-06-01

305

Oxidation of an engineered pore cysteine locks a voltage-gated K+ channel in a nonconducting state.  

UK PubMed Central (United Kingdom)

We report the use of cysteine-substituted mutants in conjunction with in situ oxidation to determine the physical proximity of a pair of engineered cysteines in the pore region of the voltage-gated...Full Text Available

1996-12-01

306

Non-cytotoxic, In Situ Gelable Hydrogels Composed of N-carboxyethyl Chitosan and Oxidized Dextran  

UK PubMed Central (United Kingdom)

A series of in situ gelable hydrogels were prepared from oxidized dextran (Odex) and N-carboxyethyl chitosan (CEC) without any extraneous crosslinking agent. The gelation readily...Full Text Available

2008-10-01

307

Nitrogen Cycling and Community Structure of Proteobacterial ?-Subgroup Ammonia-Oxidizing Bacteria within Polluted Marine Fish Farm Sediments  

UK PubMed Central (United Kingdom)

A multidisciplinary approach was used to study the effects of pollution from a marine fish farm on nitrification rates and on the community structure of ammonia-oxidizing bacteria in the underlying...Full Text Available

1999-01-01

308

Nitric Oxide and Nitrous Oxide Production by Soybean and Winged Bean during the in Vivo Nitrate Reductase Assay 1  

UK PubMed Central (United Kingdom)

This study was conducted to determine by gas chromatography (GC) and mass spectrometry (MS) the identity and the quantity of volatile N products produced during the helium-purged in vivo...Full Text Available

1986-11-01

309

Mechanism of atmospheric photooxidation of organic compounds. Reactions of alkoxy radicals in oxidation of n-butane and simple ketones  

Energy Technology Data Exchange (ETDEWEB)

The OH-initiated photo-oxidation of n-butane was used as a source of 1- and 2-butoxy radicals. Reactions producing ketones and other organic compounds are explained. Rates of photolysis were determined and are discussed.

1981-05-01

310

Intracellular Copper Does Not Catalyze the Formation of Oxidative DNA Damage in Escherichia coli?  

UK PubMed Central (United Kingdom)

Because copper catalyzes the conversion of H2O2 to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity....Full Text Available

2007-03-01

311

Increased superoxide in vivo accelerates age-associated muscle atrophy through mitochondrial dysfunction and neuromuscular junction degeneration  

UK PubMed Central (United Kingdom)

Oxidative stress has been implicated in the etiology of age-related muscle loss (sarcopenia). However, the underlying mechanisms by which oxidative stress contributes to sarcopenia have not been thoroughly...Full Text Available

2010-05-01

312

Heterogeneous catalytic alcoholysis of benzonitrile  

Energy Technology Data Exchange (ETDEWEB)

The authors investigate the possibility of the direct heterogeneous catalytic synthesis of ethylbenzoate from benzonitrile. The catalysts tested were oxides of aluminium, titanium, and vanadium. The main conversion product detected chromatographically was ethylbenzoate; benzaldehyde, benzamide, and benzanilide were also identified. Aluminium oxide was found to be the most effective catalyst.

1986-04-01

313

Genome-Wide Transcriptome Profiling of Region-Specific Vulnerability to Oxidative Stress in the Hippocampus  

UK PubMed Central (United Kingdom)

Neurons in the hippocampal CA1 region are particularly sensitive to oxidative stress (OS), whereas those in CA3 are resistant. To uncover mechanisms for selective CA1 vulnerability to OS, we...Full Text Available

2007-08-01

314

Genetic Association Analysis of NOS1 and Methamphetamine-Induced Psychosis Among Japanese  

UK PubMed Central (United Kingdom)

The neuronal nitric oxide synthase gene (NOS1) is located at 12q24, a susceptibility region for schizophrenia, and produces nitric oxide (NO). NO has been reported to play important...Full Text Available

2011-03-01

315

Functional pools of oxidative and glycolytic fibers in human muscle observed by 31P magnetic resonance spectroscopy during exercise.  

UK PubMed Central (United Kingdom)

Quantitative probing of heterogeneous regions in muscle is feasible with phosphorus-31 magnetic resonance spectroscopy because of the differentiation of metabolic patterns of glycolytic and oxidative...Full Text Available

1987-12-01

316

Enrichment of Thermophilic Propionate-Oxidizing Bacteria in Syntrophy with Methanobacterium thermoautotrophicum or Methanobacterium thermoformicicum  

UK PubMed Central (United Kingdom)

Thermophilic propionate-oxidizing, proton-reducing bacteria were enriched from the granular methanogenic sludge of a bench-scale upflow anaerobic sludge bed reactor operated at 55°C with a mixture...Full Text Available

1992-01-01

317

Endogenous Nitric Oxide Protects Bacteria Against a Wide Spectrum of Antibiotics  

UK PubMed Central (United Kingdom)

Bacterial nitric oxide synthases (bNOS) are present in many Gram-positive species and have been demonstrated to synthesize NO from arginine in vitro and in vivo. However, the physiological role...Full Text Available

2009-09-11

318

Effects of ultrafine particles-induced oxidative stress on Clara cells in allergic lung inflammation  

UK PubMed Central (United Kingdom)

BackgroundClara cell protein (CC16), the main secretory product of bronchiolar Clara cells, plays an important protective role in the respiratory tract against oxidative stress and...Full Text Available

319

Effects of comonomer and two-step oxidation on production of polyacrylonitrile-based carbon fibers. Polyacrylonitrile kei tanso sen'i no seizo ni okeru sanka jikan ni oyobosu zenkutai sen'i no kyojugo seibun oyobi dankai sanka no koka  

Energy Technology Data Exchange (ETDEWEB)

The oxidation conditions were investigated for obtaining a higher productivity in the production of high strength carbon fiber from polyacrylonitrile (PAN). The effect of incorporation of 2 % comonomer such as methyl acrylate (MA), acrylate containing carboxylate (SA), acrylamide (AAm), and hydroxyethyl acrylate (HEA) on the oxidation conditions was also investigated. The measurement of DSC and bonded oxygen content revealed that the most effective comonomer for promoting the cyclization of nitril group and the bonding of oxygen was found to be SA, and the second best was AAm. The measurement of tensile strength of carbon fiber showed that the copolymer of SA, HEA, and MA gave a high strength fiber. It took a long time to oxidize the carbon fiber when it was oxidized at a temperature on which double layer structure was not formed. To shorten the production time, a method of combining the upper limit ...

1994-06-10

320

Effects of Kombucha on oxidative stress induced nephrotoxicity in rats  

UK PubMed Central (United Kingdom)

BackgroundTrichloroethylene (TCE) may induce oxidative stress which generates free radicals and alters antioxidants or oxygen-free radical scavenging enzymes.MethodsTwenty...Full Text Available

321

Dexamethasone and nitric oxide synthase gene expression in brain.  

UK PubMed Central (United Kingdom)

Systemic administration of lipopolysaccharide (LPS), which causes endotoxemia and systemic inflammation, has been reported to induce expression of the gene for type II inducible nitric oxide synthase...Full Text Available

1997-03-01

322

Comparative analysis of nitrifying bacteria associated with freshwater and marine aquaria.  

UK PubMed Central (United Kingdom)

Three nucleic acid probes, two for autotrophic ammonia-oxidizing bacteria of the beta subdivision of the class Proteobacteria and one for alpha subdivision nitrite-oxidizing bacteria, were developed...Full Text Available

1996-08-01

323

Chemical behavior of europium oxides in- LiCI-KCI eutectic melt  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical behavior of lanthanide oxides in molten alkaline chloride media is of great concern in pyrochemical processes for advanced nuclear fuel cycle. We have studied the solubilities of various lanthanide oxides in LiCl-KCl eutectic melt. In general, lanthanide oxides appeared to be insoluble/sparingly soluble in LiCl-KCl eutectic at 723 K. However, europium oxide exhibited an abnormal behavior in solubility and redox chemistry. The solubility of europium oxide was measured to be 1-2 order of magnitude higher than those of other lanthanide oxides. This abnormal solubility may be attributable to different electrochemical behavior of europium in the same experimental conditions. Most lanthanides ion exists as trivalent oxidation states. However, we observed divalent europium dissolved in LiCl-KCl molten salt by applying electron ...

2005-06-15

324

Characterization of the stimulatory effect of high-fat diets on peroxisomal beta-oxidation in rat liver.  

UK PubMed Central (United Kingdom)

1. The effect on rat liver peroxisomal beta-oxidation of feeding diets containing various amounts of dietary oils was investigated. With increasing amounts (5-25%, w/w) of soya-bean oil an apparent,...Full Text Available

1982-08-15

325

CaF sub 2 passivation layers for high temperature superconductors  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method comprising applying a passivation layer of CaF{sub 2} to the surface of a superconductive ceramic oxide by evaporation. The CaF{sub 2} layer is effective to passivate the oxide surface without disrupting the superconductive properties.

1990-10-23

326

Blockage by acetylene of nitrous oxide reduction in Pseudomonas perfectomarinus.  

UK PubMed Central (United Kingdom)

Suspensions of denitrifying cells of Pseudomonas perfectomarinus reduced nitrate and nitrate as expected to dinitrogen; but, in the presence of acetylene, nitrous oxide accumulated when nitrate or nitrate...Full Text Available

1976-04-01

327

Association of Paraoxonase 1 (PON1) polymorphisms with osteoporotic fracture risk in postmenopausal Korean women  

UK PubMed Central (United Kingdom)

There is increasing evidence of a biochemical link between lipid oxidation and bone metabolism. Paraoxonase 1 (PON1) prevents the oxidation of low-density lipoprotein (LDL) and metabolizes biologically...Full Text Available

2011-02-28

328

Arsenic-Associated Oxidative Stress, Inflammation, and Immune Disruption in Human Placenta and Cord Blood  

UK PubMed Central (United Kingdom)

BackgroundArsenic (As) exposure during pregnancy induces oxidative stress and increases the risk of fetal loss and low birth weight.ObjectivesIn...Full Text Available

2011-02-01

329

Anions Activate the Oxidation of Indoleacetic Acid by Peroxidases from Tomato and Other Sources  

UK PubMed Central (United Kingdom)

Anionic peroxidase from tomato (Lycopersicon esculentum) fruit oxidized indoleacetic acid (IAA) slowly in the presence of Mn2+ and dichlorophenol in acetate buffers. The...Full Text Available

1990-06-01

330

Ameliorative Potential of Quercetin Against Paracetamol-induced Oxidative Stress in Mice Blood  

UK PubMed Central (United Kingdom)

The aim of the present study was to evaluate the ameliorative potential of quercetin (QC) against paracetamol (PCM)-induced oxidative stress and biochemical alterations in mice blood. A total of 36...Full Text Available

2011-07-01

331

Acetaldehyde Oxime, A Product Formed during the In Vivo Nitrate Reductase Assay of Soybean Leaves 1  

UK PubMed Central (United Kingdom)

Evolution of nitrogen oxides (NO(x), primarily as nitric oxide) from soybean (Glycine max [L.] Merr.) leaves during purged in vivo nitrate reductase assays...Full Text Available

1984-09-01

332

A simple method to systematically study oxidatively-modified proteins in biological samples and its applications  

UK PubMed Central (United Kingdom)

Increased oxidative stress with elevated levels of reactive oxygen and nitrogen species (ROS/RNS) plays an important role in the pathophysiology of many disease states. Increased ROS/RNS can...Full Text Available

2010-01-01

333

Voltage-current characteristics of point systems of metal-oxide-metal  

Science.gov (United States)

A detection theory is developed for point-contact metal-oxide-metal (MOM) systems. A system with heterogeneous oxide strongly bonded to the substrate is considered. It is shown that the form of the functional connection between the barrier heights and the ultimate compressive strength of the oxide has no substantial influence on the voltage-current characteristics of the system. Quantitative analysis indicates that a MOM system can behave as a tunnel diode and as a diode with a Schottky barrier. The model permits the determination of the optimum construction of long-life detectors based on MOM point-contacts.-

1975-10-01

334

Survey of Biodegradation of Electronic Components and ...  

Science.gov (United States)

... This pinhole process may be similar to the formation of an oxide layer in aluminum electrolytic capacitors immersed in a borax solution. ...

1991-08-01

335

Rapid and continuous hydrothermal crystallization of metal oxide particles in supercritical water  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on hydrolysis of 10 metal salt aqueous solutions of 6 metal oxides that was conducted in supercritical water. Continuous and rapid production of metal oxide fine particles was achieved by mixing a metal salt aqueous solution with preheated water fed from another line. The reaction time required was less than 2 min. Particle size, morphology, and crystal structure of the obtained metal (hydrous) oxides were examined. Particle size (20 to 600 nm) was different among the system but the size range was relatively narrow in all the cases.

1992-04-01

339

Partial oxidation of 2-propanol on perovskites  

Energy Technology Data Exchange (ETDEWEB)

Partial oxidation of 2-propanol was carried out on AB{sub 1-x}B`{sub x}O{sub 3} (A=Ba, B=Pb, Ce, Ti; B`=Bi, Sb and Cu) type perovskite oxides. Acetone was the major product observed on all the catalysts. All the catalysts underwent partial reduction during the reaction depending on the composition of the reactant, nature of the B site cation and the extent of substitution at B site. The catalytic activity has been correlated with the reducibility of the perovskite oxides determined from Temperature Programmed Reduction (TPR) studies. (orig.)

1998-12-31

340

Oil shale oxidation at subretorting temperatures  

Energy Technology Data Exchange (ETDEWEB)

Green River oil shale was air oxidized at subretorting temperatures. Off gases consisting of nitrogen, oxygen, carbon monoxide, carbon dioxide, and water were monitored and quantitatively determined. A mathematical model of the oxidation reactions based on a shrinking core model has been developed. This model incorporates the chemical reaction of oxygen and the organic material in the oil shale as well as the diffusivity of the oxygen into the shale particle. Diffusivity appears to be rate limiting for the oxidation. Arrhenius type equations, which include a term for oil shale grade, have been derived for both the chemical reaction and the diffusivity.

1980-06-01

341

JENDL-4.0: A database on neutron-induced reactions for nuclear science and engineering  

International Nuclear Information System (INIS)

... compilation fission products j codes mixed oxide fuels neutron reactions

2010-12-01

343

Effect of Yttrium on the Microstructure of Titanium Alloys,  

Science.gov (United States)

... Title : Effect of Yttrium on the Microstructure of Titanium Alloys,. ... The yttrium was added in the melting stage as an oxide or in the elemental form. ...

344

Economic Evaluation of Carbon Dioxide and Nitrous Oxide Emission Reducti\\\\\\rons in Industry in the EU  

Wastenet

However, these intra-industrial structural changes are not considered in this bottom-up study.

345

Cost sensitivity analysis for mixed-oxide fuel cycles  

International Nuclear Information System (INIS)

(1978). United States Quan, B. Becker, M. Harris, DR Rensselaer Polytechnic

346

Characterization of Metal Oxide and Silica-Based Electrodes  

Energy Technology Data Exchange (ETDEWEB)

Objective of the project is characterization of electrode reactions in molten salt by using metal oxides and silica-based electrode. The scope of project are characterization of metal oxide properties in molten salt and miniaturization of 3-electrode electrochemical test cell. Electrochemical micro-cell for actinide-LiCl-KCl molten salt was newly designed. Electroless and electrochemical deposition technique was applied to Mo coating on quartz tube. From the design of electrode and 3-electrode electrochemical cell suitable for the tests in molten salt electrolyte, so it is anticipated to get the information on the electrochemical behavior of metallic electrode in molten salt and to secure the information on oxidation/reduction behavior of actinide

2010-05-15

347

Behavior of Aqueous Electrolytes in Steam Cycles - The Final Report on the Solubility and Volatility of copper(I) and Copper(II) Oxides  

Energy Technology Data Exchange (ETDEWEB)

Measurements were completed on the solubility of cupric and cuprous oxides in liquid water and steam at controlled pH conditions from 25 to 400 C (77 to 752 F). The results of this study have been combined with those reported from this laboratory in two previous EPRI reports to provide a complete description of the solubility of these oxides and the speciation of copper dissolved in liquid water and steam as a function of oxidation state, temperature, pH, and in the case of steam, pressure. These constitute the first set of reliable data for cuprous oxide solubility over this range of conditions. For the more intensively studied CuO case, agreement was found between our results and those of previous studies of its solubility in steam, whereas only partial agreement was evident for its solubility in liquid water. For both oxides this disagreement often amounted to orders of ...

2004-05-01

348

Ammoxidation of methanol to produce hydrogen cyanide  

Energy Technology Data Exchange (ETDEWEB)

Promoted antimony phosphate oxide complexes are excellent catalysts for the ammoxidation of methanol to HCN especially at high methanol throughputs.

1985-04-16

349

Thermal wet oxidation of GaP and Al{sub 0.4}Ga{sub 0.6}P  

Science.gov (United States)

Thermal wet oxidations of GaP and Al{sub 0.4}Ga{sub 0.6}P at 650 degree sign C for various times have been performed. Comparisons are made on oxidation rates and post oxidation morphology. Transmission electron microscopy shows that when oxidizing GaP, polycrystalline monoclinic GaPO{sub 4}{center_dot}2H{sub 2}O forms without noticeable loss of phosphorus. Oxidation for 6 h or more leads to poor morphology resulting in cracks and detachment. A thickness expansion of about 2.5-3 times is noticed as a result of oxidation. In contrast, oxidized Al{sub 0.4}Ga{sub 0.6}P exhibits much better morphology without cracks or detachment from the substrate. The oxide has an almost amorphous-like microstructure. The oxidation process shows typical diffusion-limited reaction at long anneals. Preliminary work on the ...

2000-08-21

350

The liquid phase oxidation of n-butane: a search for plausible mechanisms  

Energy Technology Data Exchange (ETDEWEB)

This articles deals with an approach that has given some key information about the mechanisms of the liquid phase oxidation of butane to acetic acid. This procedure has been developed over the last 34 years; however, much of what will be discussed represents a synthesis of previous insights. Many of the observations are relatively recent and have not been previously published. In principle, this approach should be applicable to many oxidation processes. (orig.)

1998-12-31

351

The Friction of Vehicle Brake Tandem Master Cylinder  

International Nuclear Information System (INIS)

The behaviour of an elastomeric seal for vehicle brake Tandem master cylinder is measured and analyzed in temperature and brake fluids changed. Working conditions are simulated for different piston rod velocity and cylinder supply pressure, in temperature rising, brakefluid boundary and Nanoaluminum oxide brakefluid oxide brakefluid lubrication. The result shows that Nanoaluminum oxide brakefluid with its ball shape can highly reduce friction coefficient to avoid seal excessive wear and reduce slick slip in brake applications.

2006-10-01

352

The Fenton oxidation mechanism: reactivities of biologically relevant substrates with two oxidizing intermediates differ from those predicted for the hydroxyl radical.  

UK PubMed Central (United Kingdom)

The application of kinetic probes that allow one to determine relative reactivities of biologically relevant substrates with oxidizing intermediates in the Fenton reagent (H2O2 plus Fe2+ in acidic aqueous...Full Text Available

1994-07-05

353

The Conversion of Nitrite to Nitrogen Oxide(s) by the Constitutive NAD(P)H-Nitrate Reductase Enzyme from Soybean 1  

UK PubMed Central (United Kingdom)

A two-step purification protocol was used in an attempt to separate the constitutive NAD(P)H-nitrate reductase [NAD(P)H-NR, pH 6.5; EC 1.6.6.2] activity from the nitric oxide and nitrogen dioxide (NO(x))...Full Text Available

1988-10-01

354

Single-crystalline cadmium telluride anodic oxidation kinetics  

Science.gov (United States)

The authors have determined quantitative characteristics for oxide films forming on (111) surfaces of cadmium telluride single crystals on anodic oxidation in 0.1 M KOH: the constants in the Guenterschulze-Betz equation and the film growth constant, which is 2.4 nm/V, from which the activation energy for cadmium telluride electrooxidation has been calculated.

1988-10-10

355

Quartz ceramics alloying  

International Nuclear Information System (INIS)

The following methods of quartz ceramics alloying were considered: alloying of initial quartz glass; introduction of alloying additive into water slip of quartz glass; porous materials impregnation with salt aqueous solutions and subsequent salt thermal decomposition with formation of stable oxides in pores of ceramics. Oxygen free compounds BN, SiB_4, SiC, Si_3N_4, REM oxides and transition metal oxides were used as alloying additives. Main properties of the materials and compositions obtained are presented.

356

Electrochemical oxidation of curium(III) in potassium carbonate solution  

International Nuclear Information System (INIS)

During electrolysis of a "2"4"8Cm(III) solution in 2M K_2CO_3 at pH=13, partial oxidation of curium to a higher oxidation state, probably Cm(IV), was observed. The absorption spectra of Cm(III) and Cm(IV) in K_2CO_3 solution were recorded and the molar extinction coefficients of main absorption bands of curium were evaluated. (author).

1986-11-01

357

Catalytic hydrocarbon reactions over supported metal oxides. Progress report, April 1, 1994--January 31, 1995  

Energy Technology Data Exchange (ETDEWEB)

Oxide catalysis plays a central role in hydrocarbon processing and improvements in catalytic activity or selectivity are of great technological importance because these improvements will translate directly into more efficient utilization of hydrocarbon supplies and lower energy consumption in separation processes. An understanding of the relationships between surface structure and catalytic properties is needed to describe and improve oxide catalysts. Our approach has been to prepare supported oxides that have a specific structure and oxidation state and then employ these structures in reaction studies. Our current research program is focused on studying the fundamental relationships between structure and reactivity for two important reactions that are present in many oxide-catalyzed processes, partial oxidation and carbon-carbon bond formation. ...

1995-01-31

358

uv photobiology: postreplication repair. [Escherichia coli, synchrotron radiation  

Science.gov (United States)

The following topics are discussed: insertion of incorrect bases in DNA; ability of DNA polymerase to copy uv-irradiated DNA; role of enzymes in repair of DNA; effects of uv radiation on molecular weight of DNA; photoreactivation; repair of DNA in Escherichia coli and xp cells following uv radiation; and synchrotron radiation studies on DNA repair. (HLW)

1978-01-01

361

Tumorigenic and tumoricidal actions of ionizing radiations  

Energy Technology Data Exchange (ETDEWEB)

The book is divided into two approximately equal parts. The first four chapters are relatively lengthy and cover the basic principles of radiation biology, carcinogenesis and therapy, along with a brief introduction to radiological physics to orient the reader without background in this specialized related discipline. The remainder consists of twenty-four relatively brief chapters, each covering the radiation biology of a specific organ, tissue, or systems tissues, with emphasis on the tumorigenic and tumoricidal action of ionizing radiations.

1983-01-01

362

The influence of stray radiation on image quality  

International Nuclear Information System (INIS)

The present state of knowledge on the influence of stray radiation on image quality and its physical description and quantification is summarized. Experimental results on the influence of physical parameters on the fraction of scattered radiation and the effect of scatter reduction by air gap technique and secondary radiation grids are committed. Open theoretical and practical problems and the limitations of common methods of scatter reduction are pointed out. (author).

365

Surprising collectivity in neutron-rich iron isotopes  

International Nuclear Information System (INIS)

... VDPEAZ (Bonn 2010 issue) NUCLEAR PHYSICS AND RADIATION PHYSICS

2010-03-15

370

Space Radiation Detector with Spherical Geometry  

Science.gov (United States)

A particle detector is provided, the particle detector including a spherical Cherenkov detector, and

2011-01-01

372

Solar Radiation Pressure Binning for the Geosynchronous Orbit  

Science.gov (United States)

Orbital maintenance parameters for individual satellites or groups of satellites have traditionally

2011-01-01

373

Self-filling and self-purging apparatus for detecting spontaneous radiation from substances in fluids  

Energy Technology Data Exchange (ETDEWEB)

Disclosed herein is a radiation detector providing for the in situ automatic sampling of fluids containing substances emitting radiation, especially Cerenkov radiation. The detector permits sampling within well casings and is self-purging such that no additional provisions must be established for the storage and disposal of contaminated fluids.

1993-01-01

375

Radiological equipment for emergencies  

Energy Technology Data Exchange (ETDEWEB)

A brief guide to training and equipment needed to effectively manage victims of radiation accidents. (DT)

1985-01-01

379

Radiation-annealing hardening of vanadium  

International Nuclear Information System (INIS)

A study is made of the mechanical properties of vanadium irradiated with fast neutrons up to dose 8.6.10"-"4 dpa, as a function of the temperature of post-radiation annealing. The radiation-annealing hardening (RAH) effect is observed at 300"oC, in agreement with previous studies. It is established for the first time that RAH is accompanied by fall in ductility. A phenomenological model is described which explains the dependence of RAH on radiation dose and temperature, as well as on the content of chemically active alloying impurities. (author).

380

Radiation processing used in forestry in Thailand  

Energy Technology Data Exchange (ETDEWEB)

A summary is presented of research being carried out in Thailand on the preparation of irradiation-impregnated wood.

1981-01-01

381

Radiation effects on the shoot tip culture of chrysanthemum  

International Nuclear Information System (INIS)

Japanese (Mar 1974). Japan Mabuchi, Toshio Kuwada, Hikaru . Kagawa Univ.,

384

Radiation and fetal brain development  

International Nuclear Information System (INIS)

(4 Sep 1986). United Kingdom Zamenhof, Stephen . California Univ., Los

385

Radiation Protection of the Organism (Selected Chapters)  

Science.gov (United States)

... biologically important compounds is sharply lowered with passage of the solutions to the cell an organ, where their sensitivity ...

1970-12-11

386
388

Possibility of production of new superheavy nuclei in complete fusion reactions  

International Nuclear Information System (INIS)

... of Sciences (Poland) [5.48 Megabytes] NUCLEAR PHYSICS AND RADIATION

2008-09-01

389

Nuclear physics with a free electron laser  

International Nuclear Information System (INIS)

... radiation parity photonuclear reactions polarized beams resonance

391

Multi-spectral schottky barrier infrared radiation detection array  

Energy Technology Data Exchange (ETDEWEB)

A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array.

1983-12-27

392

Multi-spectral schottky barrier infrared radiation detection array  

International Nuclear Information System (INIS)

A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array.

394

Kinetics of low-temperature radiation hardening of metallic materials under irradiation  

British Library Electronic Table of Contents (United Kingdom)

A formula is obtained which describes the kinetics of low-temperature radiation hardening caused by creation of dislocation loops of interstitial type during irradiation. The radiation hardening of aluminum and vanadium is estimated using this formula and results of experiments on studying processes of nucleation and growth of interstitial dislocation loops in these materials by transparent electron microscopy. It is shown that the proposed formula is valid for description of the kinetics of low-temperature radiation hardening.

2011-01-01

396

Infrared processes in the auroral zone  

International Nuclear Information System (INIS)

... aurorae carbon dioxide emission spectra infrared radiation nitrogen nitrogen

8432-01-01

398

Induced radiation during scattering of channeled electrons and positrons by point defects  

Energy Technology Data Exchange (ETDEWEB)

In scattering of channeled particles by point defects and in emission of gamma rays in the spontaneous-radiation spectral region conditions are attained where the momentum transferred to the defect is taken up by the crystal as a whole. This leads to coherent and interference effects in the radiation from the crystal defects. When the longitudinal momentum transferred is zero, an induced radiation effect appears in the transitions between the states of transverse motion.

1984-12-01

402

ISR site  

CERN Document Server

A last look at the green field, in the triangular wedge of land stray radiation near the CERN accelerators.

1965-01-01

403

Free radicals in lysozyme reacted with peroxidizing methyl linoleate  

International Nuclear Information System (INIS)

... electron spin resonance gamma radiation lipids lyophilization lysozyme radicals

404

Four cases of bowel perforation following radiation therapy for cervical cancer  

Energy Technology Data Exchange (ETDEWEB)

External radiation dose exceeded 5,000 rad in three cases, and intravaginal radiation dose was 5,000 rad in one case. Radiation damage including perforation was seen in the end of ileus in one case, in the sigmoid and rectum in two cases, and in the end of ileus, sigmoid and rectum in the last case. Satisfactory results were obtained by the removal of the ileocecum in the case of the damage in the end of the ileus. However, only colostomy was performed for the damage in the sigmoid and rectum.

1984-10-01

405

Experts' discussion on the possibility of quantification of the radiation hazard  

International Nuclear Information System (INIS)

Due to the intensity and vast number of subjects, this Bremen experts' discussion, too, could discuss only part of the problem of the possibilitiy to quantify the radiation hazard. One preliminary result is that there is no scientific proof of the harmlessness of radiation exposure during normal operation of a nuclear power plant, either within the plant or in its vicinity. Other results are that some important questions can not be answered yet, and that there are important hints on the dangers even of low radiation doses. (GL).

1978-01-01

408

Effective dose equivalent in nuclear medicine investigations  

International Nuclear Information System (INIS)

... radiation hazards hazards health hazards MEDICINE. SOMATICALLY

1984-05-07

411

Development of a real-time, neutron and gamma dosimeter  

Energy Technology Data Exchange (ETDEWEB)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of {sup 6}Li and {sup 7}Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of {sup 6}Li and {sup 7}Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

2001-07-01

412

Development of a real-time, neutron and gamma dosimeter  

International Nuclear Information System (INIS)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of "6Li and "7Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of "6Li and "7Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

2001-06-10

413

Cooperative spontaneous emission from two different atoms  

International Nuclear Information System (INIS)

The total radiation rate, angular distribution of the emitted energy and photon correlations of the cooperative spontaneous radiation from two atoms with different resonance frequencies and spontaneous decay rates are calculated. Contrary to the case of two identical atoms oscillations appear in the total radiation rate and the spatial distribution of the total number of emitted photons differs from the single-atom radiation pattern. The effect of the dipole-dipole near-field interaction on the time evolution of the atomic system is discussed. (author).

1986-01-01

415

Comparing two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the hypofractionated treatment of high-risk prostate cancer  

UK PubMed Central (United Kingdom)

BackgroundTo compare two strategies of dynamic intensity modulated radiation therapy (dIMRT) with 3-dimensional conformal radiation therapy (3DCRT) in the setting of hypofractionated...Full Text Available

416

Cluster-loop structure influence on molybdenum radiation hardening  

International Nuclear Information System (INIS)

Results on defect structure study and degree of molybdenum radiation hardening irradiated by fission neutrons and medium energy alpha-particles are presented. It is shown that molybdenum irradiation by alpha-particles and neutrons leads to different degree of material hardening for the same damage level. It is established that molybdenum radiation hardening is mainly defined by radiation defect clusters visible in electron microscope whose coefficient of rigidity depends on their size. 5 refs.; 6 figs.; 2 tabs. (author).

1990-05-22

422

About tachyons  

International Nuclear Information System (INIS)

... Part A: The electromagnetic radiation of a charged tachyon. Part B: Some

423

ASE FILE  

Science.gov (United States)

radionuclide X-ray fluorescence analysis: the resolving power of the ... The radiation detectors used in radionuclide X-ray fluorescence ...

425

On the Role of Convection and Turbulence for Tropospheric Ozone and its Precursors  

International Nuclear Information System (INIS)

The aim of the work in this thesis is to investigate the convective and diffusive transport in the TM chemistry transport model, and to investigate some aspects of the consequences for NOx. The large inaccuracy and uncertainty in the description of processes like convection and turbulent diffusion, the strong dependence of the radiative forcing of ozone on its vertical distribution, and the strong dependence of the ozone production on the distribution of NOx, are the main motivation. The availability of the ERA-40 data, where convective data and vertical diffusion coefficients are archived, allows a study of the effect of different convective mass flux sets, and different vertical diffusion coefficients on the model-simulated distribution of tracers. In this thesis the following questions are addressed : (1) How large is the sensitivity of the (model simulated) distribution of ozone and nitrogen oxides on (the) convection (parameterisation)?; ...

426

Theory of edge radiation  

CERN Document Server

We formulate a complete theory of Edge Radiation based on a novel method relying on Fourier Optics techniques. Similar types of radiation like Transition Undulator Radiation are addressed in the framework of the same formalism. Special attention is payed in discussing the validity of approximations upon which the theory is built. Our study makes consistent use of both similarity techniques and comparisons with numerical results from simulation. We discuss both near and far zone. Physical understanding of many asymptotes is discussed. Based on the solution of the field equation with a tensor Green's function technique, we also discuss an analytical model to describe the presence of a vacuum chamber. In particular, explicit calculations for a circular vacuum chamber are reported. Finally, we consider the use of Edge Radiation as a tool for electron beam diagnostics. We discuss Coherent Edge ...

2008-01-01

427

Radiative corrections to the atomic levels in a periodic electromagnetic field  

Energy Technology Data Exchange (ETDEWEB)

The influence of a periodic electromagnetic field on the radiative corrections to the atomic energy levels is studied for the case of ''strong fields'' for which the interaction between the atom and field is of the order or greater than the radiative effects. The analysis is carried out on the basis of the Schwinger-Dirac equation for the propagation function of a bound electron in the field and on the basis of the density matrix in the Furry representation. It is shown that in the strong field approximation the radiative shifts and widths are manifest as radiative corrections to the quasi-energies. In super-high resolution experiments intensity effects in the radiative corrections to the atomic levels are obtained in the case of single-photon resonance. Some multiphoton processes are condidered by taking into account the effect of the field on ...

1982-12-01

428

Biological radiation effects  

International Nuclear Information System (INIS)

The stages of processes leading to radiation damage are studied, as well as, the direct and indirect mechanics of its production. The radiation effects on nucleic acid and protein macro moleculas are treated. The physical and chemical factors that modify radiosensibility are analysed, in particular the oxygen effects, the sensibilization by analogues of nitrogen bases, post-effects, chemical protection and inherent cell factors. Consideration is given to restoration processes by excision of injured fragments, the bloching of the excision restoration processes, the restoration of lesions caused by ionizing radiations and to the restoration by genetic recombination. Referring to somatic effects of radiation, the early ones and the acute syndrome of radiation are discussed. The difference of radiosensibility observed in mammalian cells and main observable alterations in tissues and ...

1976-01-01

429

A study on the real-time radiation dosimetry measurement system based on optically stimulated luminescence  

International Nuclear Information System (INIS)

The optically stimulated luminescent (OSL) radiation dosimeter technically surveys a wide dynamic measurement range and a high sensitivity. Optical fiber dosimeters provide capability for remote monitoring of the radiation in the locations which are difficult-to-access and hazardous. In addition, optical fiber dosimeters are immune to electrical and radio-frequency interference. In this paper, a novel remote optical fiber radiation dosimeter is described. The optical fiber dosimeter takes advantage of the charge trapping materials CaS:Ce, Sm that exhibit OSL. The measuring range of the dosimeter is from 0.1 to 100 Gy. The equipment is relatively simple and small in size, and has low power consumption. This device is suitable for measuring the space radiation dose and also can be used in high radiation dose condition and other dangerous radiation occasions. ...

2008-05-01

430

Radiological concepts in radiotherapy  

International Nuclear Information System (INIS)

The atomic explosions in Hiroshima and Nagasaki made the name radiation itself become a nightmare. Notwithstanding this, radiation continued to serve the mankind specially in diagnosis of several human diseases and in the treatment of intractable malignancies. With their latest research tools biologists have now shown a significant shift in the earlier paradigm; even the concept that radiation initiates cancer appears to be no longer tenable. On the contrary, selective radiation doses inhibit growth of cancer cells and radiation in combination with many chemotherapeutic drugs, radiosensitizing chemicals and/or hyperthermia, is emerging as a new modality for cancer treatment which offers high therapeutic advantages. In addition, the deleterious effects of radiation can now be strategically counter poised by the use of many drugs and chemicals. This has been ...

431

Treatment of a waste salt delivered from an electrorefining process by an oxidative precipitation of the rare earth elements  

British Library Electronic Table of Contents (United Kingdom)

For the reuse of a waste salt from an electrorefining process of a spent oxide fuel, a separation of rare earth elements by an oxidative precipitation in a LiCl-KCl molten salt was tested without using precipitate agents. From the results obtained from the thermochemical calculations by HSC Chemistry software, the most stable rare earth compounds in the oxygen-used rare earth chlorides system were oxychlorides (EuOCl, NdOCl, PrOCl) and oxides (CeO2, PrO2), which coincide well with results of the Gibbs free energy of the reaction. In this study, similar to the thermochemical results, regardless of the sparging time and molten salt temperature, oxychlorides and oxides were formed as a precipitant by a reaction with oxygen. The structure of the rare earth precipitates was divided into two sha...

2009-01-01

432

Surface oxidation of Co2+ and its dependence on ligand coordination number in silica polyamine composites  

British Library Electronic Table of Contents (United Kingdom)

Coordination of CoCl2 solutions to the silica polyamine composite, WP-1, made with the branched polymer polyethylenimine (PEI) shows irreversible binding resulting from surface oxidation of the Co2+-Co3+. This is not the case for the silica polyamine composite BP-1 made with the linear polymer polyallylamine where reversible binding and no oxidation is observed. These observations suggested that oxidation of the cobalt was related to the greater coordination number available with the branched polyamine relative to the linear polyamine. A study of the kinetics of cobalt binding to WP-1 indicated initial loading of Co2+ at relatively low coordination number followed by desorption of Co2+ leading to oxidation and irreversible binding. Exclusion of oxygen from the composite-cobalt solution mix...

2010-01-01

433

Process for the recirculation of nitrogen oxides  

Energy Technology Data Exchange (ETDEWEB)

The invention is regeneration and recirculation of nitrogen oxides in the exhaust gas of a nitric acid plant without using any material current and heat energy other than that generated in the process of producing nitric acid. Nitrogen oxide is recovered by at least two adsorbers each containing an acid resistant zeolite molecular sieve and operating in an alternate heat cycle; adsorption occurring at 20-40 degrees C and regeneration at 300-350 degrees C. The hot gas exiting from the oxidation U used in the production of nitric acid is used to regenerate the adsorbers and the nitrogen oxides set free during the said regeneration are introduced into the main feed stream of the nitric acid plant. In the final stage of the regeneration the adsorbers are cooled by rinsing them with exhaust gas or air at a temperature of 20-40 degrees C.

1983-01-04

434

Oxidation studies of #beta#-sialon ceramics containing amorphous and / or crystalline intergranular phases  

International Nuclear Information System (INIS)

#beta#-sialon ceramics of equal overall compositions but containing amorphous, partly crystalline and almost completely crystalline intergranular phase(s) have been oxidized in oxygen at 1350 deg C for 20 hours. The obtained weight gain curves do not follow the parabolic rate law (#DELTA#W/A_0)"2= k_pt + #beta#. To the extent that crystallization occurs in the oxide scale during the oxidation experiment, the amorphous cross section area through which oxygen most easily diffuses will decrease with time. A brief description of this new rate law is given, and the obtained oxidation curves will be discussed within that framework. 4 refs., 2 tabs., 2 figs.

435

Oxidation of polycaprolactone to induce compatibility with other degradable polyesters  

British Library Electronic Table of Contents (United Kingdom)

Chemical modification of poly(?-caprolactone) PCL by oxidation with potassium permanganate in solution was investigated. According to the data obtained from Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance 1H NMR, after the oxidation reactions the PCL chains exhibited new functional groups (vinyl and hydroxyl) and possible intermolecular recombination, producing an oxidized-polycaprolactone (PCL-OX). Solution viscometry indicated that degradation also occurred during the oxidation reactions (30% drop in viscosity average molecular weight was detected). Differential scanning calorimetry (DSC) also indicated that PCL was chemically modified and degraded. The successive self-nucleation/annealing (SSA) treatment confirmed that a reduction (or interruption) in line...

2007-01-01

436

One-electron redox reactions of pyrazolin-5-ones. A pulse radiolysis study of antipyrine and analogues  

Energy Technology Data Exchange (ETDEWEB)

One-electron oxidation of several derivatives of pyrazolin-5-one, including the drug antipyrine, were studied by pulse radiolysis of aqueous solutions. All the compounds were found to be oxidized by Br2 rapidly but considerably more slowly by weaker oxidants, such as peroxyl radicals. From redox equilibria using p-methoxyphenol and N,N,N',N'-tetramethyl-p-phenylenediamine as reference compounds, the one-electron oxidation potentials of the methyl-substituted 2-pyrazolin-5-ones were found to be in the range of 0.32-0.39 V versus normal hydrogen electrode. The relevance of these findings to the properties of the drug nafazatrom is discussed. Antipyrine was found to have a much higher oxidation potential, estimated as 1.2-1.5 V, which is rationalized on the basis of the phenyl substitution and lack of resonance stabilization of the radical cation.

1985-10-01

437

Chemical composition and electronic structure of passive films formed on Alloy 600 in acidic solution  

Energy Technology Data Exchange (ETDEWEB)

The chemical composition and the semiconducting properties of passive films formed on nickel based alloy (Alloy 600) in acidic sulphate solution, pH 2.0 at room temperature were studied using Auger analysis, voltammetric techniques and the Mott-Schottky approach. The results obtained revealed that the presence of both chromium and mixed nickel-iron oxides in the films leads to the development of a p-n heterojunction, which controls their electronic structure, similarly manner to the case of stainless steels and Alloy 600 in borate buffer solution. This behavior has been interpreted as representing of an oxide system, which has a duplex character, with an inner p-type semiconducting region, mainly formed by chromium oxide and an outer n-type semiconducting region, containing iron oxide. It could also be observed that the nickel oxide present in the films acts as a barrier layer ...

2008-03-15

438

Chemical composition and electronic structure of passive films formed on Alloy 600 in acidic solution  

International Nuclear Information System (INIS)

The chemical composition and the semiconducting properties of passive films formed on nickel based alloy (Alloy 600) in acidic sulphate solution, pH 2.0 at room temperature were studied using Auger analysis, voltammetric techniques and the Mott-Schottky approach. The results obtained revealed that the presence of both chromium and mixed nickel-iron oxides in the films leads to the development of a p-n heterojunction, which controls their electronic structure, similarly manner to the case of stainless steels and Alloy 600 in borate buffer solution. This behavior has been interpreted as representing of an oxide system, which has a duplex character, with an inner p-type semiconducting region, mainly formed by chromium oxide and an outer n-type semiconducting region, containing iron oxide. It could also be observed that the nickel oxide present in the films acts as a barrier layer ...

2008-03-01

439

The influence of scattered radiation on recording systems and quality-assurance test parameters  

International Nuclear Information System (INIS)

Scattered radiation generated in patient and imaging system has to be considered when quality-assurance tests involve dose detection or image-quality estimations. Measurement of automatic-exposure control dose can be altered by backscattering from intensifying screens of more than 10% and the equipment transmission factor can be overestimated up to a factor of 10 when only primary radiation is used. The sensitivity of intensifying screens depends on the angle of incidence of the radiation and so primary and scattered radiation are detected differently. The quality-control aspects of anti-scatter grids are discussed. (author).

1988-02-23

440

The influence of scattered radiation on recording systems and quality-assurance test parameters  

International Nuclear Information System (INIS)

Scattered radiation generated in patient and imaging system has to be considered when quality-assurance tests involve dose detection or image-quality estimations. Measurement of automatic-exposure control dose can be altered by backscattering from intensifying screens of more than 10% and the equipment transmission factor can be overestimated up to a factor of 10 when only primary radiation is used. The sensitivity of intensifying screens depends on the angle of incidence of the radiation and so primary and scattered radiation are detected differently. The quality-control aspects of anti-scatter grids are discussed. (author).

441

Study of emission of Cerenkov radiation by tachyons  

International Nuclear Information System (INIS)

The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation. (author).

442

Standard radiation monitoring at Sendai nuclear power station  

International Nuclear Information System (INIS)

Standard radiation monitoring has been conducted at Sendai nuclear power station for the purpose of estimation of 'source activity' during refueling outage and evaluation of countermeasures to reduce dose rate. Selected objects of the monitoring are radiation dose rate at maintenance area, radiation field at each equipment and piping, coolant chemistry and plant operation condition. Monitored data indicates that 'source activity' variation can be estimated to some extent using influential factors, and that evaluation of change of loose crud activity, which is presumed to be represented by the dose rate at letdown heat exchanger, is necessary to further explain change in radiation field at main work area. (author).

443

Somatic radiation risk in X-ray diagnostics  

Energy Technology Data Exchange (ETDEWEB)

The authors give a survey of the somatic radiation risk in X-ray diagnostics. A somatic dose index is calculated for different examination methods containing the organ doses to the red bone marrow, the lung, the female breast, and the thyroid gland and evaluating their somatic significance. If this somatic dose index by which the individual radiation risk is described, is multiplied by the examination frequencies per year in the German Federal Republic, one gets the somatically significant dose index, which is a measure of the collective somatic radiation risk. In this sense, mammography has the highest, and dental radiography the lowest collective radiation risk.

1983-12-01

444

Somatic radiation risk in X-ray diagnostics  

International Nuclear Information System (INIS)

The authors give a survey of the somatic radiation ris in X-ray diagnostics. A somatic dose index is calculated for different examination methods containing the organ doses to the red bone marrow, the lung, the female breast, and the thyroid gland and evaluating their somatic significance. If this somatic dose index by which the individual radiation risk is described, is multiplied by the examination frequencies per year in the German Federal Republic, one gets the somatically significant dose index, which is a measure of the collective somatic radiation risk. In this sense, mammography has the highest, and dental radiography the lowest collective radiation risk. (orig.).

1983-01-01

445

Radiation-stimulated diffusion of aerosols  

Energy Technology Data Exchange (ETDEWEB)

The diffusion coefficient of particles in radioactive gases has been calculated with account of random wandering of aerosols (occurrence of local fields affecting the particles; recoils accompanying radiation emitted by particles, etc.). To determine the diffusion coefficient, the method of Fokker-Planck equation derivation was used. A formula is presented for calculating the radiation-stimulated diffusion coefficient. A linear growth of the diffusion coefficient with radioactivity is noted according to the formula, the diffusion coefficient is mainly determined by the field in the radiation damage region. The aerosol radioactivity may result in a more rapid deposition of aerosols in the pipelines and aerosol purification systems. The diffusion rate grows not only in the presence of intrinsic radioactivity but in case of external radiation exposure as well.

1984-04-01

446

Radiation-induced chemical modification of wood  

International Nuclear Information System (INIS)

The results of theoretical and experimental investigations, describing the effect of ionizing radiation on wood and its main components and methods for production of wood-plastic composites by means of radiation-induced chemical modification are generalized. Domestic and foreign experience in their production is systematized; physico-mechanical characteristics of new material, simulation and calculation of irradiating devices, as well as calculation and experimental study of #gamma#-radiation attenuation both by wood material and by wood of different species are given. Gamma sources ("6"0Co isotope, a hot loop of a nuclear reactor) as well as electron accelerators are considered as ionizing radiation sources.

1985-01-01

447

RADSOLVER: a computer program for calculating spectrally-dependent radiative heat transfer in solar cavity receivers  

Energy Technology Data Exchange (ETDEWEB)

RADSOLVER is a computer program which calculates the radiation energy transport in cavity type receivers having an arbitrary number of apertures through which collimated beams of solar radiation enter. In contrast to the common assumption of gray (or semi-gray) surfaces used in the modeling of radiation transport, RADSOLVER accounts for the wavelength-dependence of emission, absorption and reflection with a band model of the radiative properties. It is intended that this report serve both as an instruction manual for the use of the RADSOLVER code and a vehicle for presenting the underlying theory. Illustrative examples along with input and output are presented.

1981-09-01

448

Practice and experience of occupational exposure control in the outages of Daya Bay Nuclear Power Plant  

International Nuclear Information System (INIS)

Outage is a specific period of time for radiation protection in a nuclear power plant, in which the radiation risk and collective dose are both at the highest level. In this article, the practice and experience of occupational exposure control in the outages of Daya Bay Nuclear Power Plant are introduced through following aspects: early involvement in outage preparation by radiation protection service, control of source term, radiation protection and safety management in the outage implementation processes, the effectiveness of the plant's safety management network and overall involvement of all staffs of the plant, experience feedback and continuous improvement in radiation protection management, etc

2004-05-01

449

New concepts in risk assessment for patients with radiological treatment  

International Nuclear Information System (INIS)

In radiation risk assessment it must be differentiated between somatic and genetic effect on the one hand as well as between stochastic and non-stochastic effect on the other. According to definitions of the ICRP report 26 the limit for the dose equivalent of all tissues prevents non-stochastic radiation effects. With stochastic radiation effects probably exist no threshold doses; therefore the ALARA principle must be applied concerning radiation protection. The individual risk by stochastic radiation effects in its linear, linear-quadratic and quadratic extrapolations, respectively, is discussed in detail. The effective stochastic dose equivalent (H/sub eff/) as well as collective dose and collective damage are outlined.

1986-01-01

450

Evaluation of the residual radiation field in the proton accelerator facility of the Proton Engineering Frontier Project (PEFP) in Korea  

British Library Electronic Table of Contents (United Kingdom)

In Korea, the Proton Engineering Frontier Project (PEFP) is building a proton linear accelerator facility with energy up to 100MeV and a beam current of 20mA. In this study, a radiation field after shutdown in the accelerator facility of the PEFP was evaluated for the purpose of the radiation shielding by using MCNPX code. A facility modeling was performed for the accelerator tunnel building, accelerator chain, target rooms and beam experiment hall. And radiation source terms were evaluated in the facility. With this facility, model and radiation source terms, the concentration of 41Ar was evaluated and the cooling time satisfying regulation in Korea was calculated.

2007-01-01

451

Difference between delayed radiation-necroses of the cerebral hemispheres and midline: its bearing in radiation therapy  

Energy Technology Data Exchange (ETDEWEB)

Delayed cerebral necroses after irradiation are to be divided into hemispheric and midline lesions, as they differ from each other in several aspects. Apart from the symptoms, they are differing in the duration of latency, in the course and prognosis, and also with regard to morphology. Though there is no doubt that radiation tolerance of cerebral midline structures is relatively limited, on biological grounds, evidence of a difference between the tolerated doses could not be given from the existent inhomogeneous radiation data, with the help of the NSD-concept. Radiation planning for the region of the head, nevertheless, carefully should avoid in every case to involve the structures of the cerebral midline.

1980-08-01

452

Decommissioning and dismantling. Examination of the radiation hardening of electronic components. Final report  

International Nuclear Information System (INIS)

Remote-controlled handling systems are required for work to be done in the decommissioning and dismantling of nuclear facilities. These systems are equipped with electronic devices suitable for use in working environments affected by ionizing radiation. The publication explains the step-wise progress achieved for improving the radiation resistance of electronic devices with the example of a four-quadrant controlling device for the motors of a manipulator. The radiation resistance of the device could be enhanced to radiation energies of 5.500 Gy. This means that a manipulator vehicle equipped with this controlling device can take up to approx. 15 kGy all in all, taking into account its own shielding properties. (DG).

453

Comparison and analysis of results of ? radiation level investigation around Daya Bay  

International Nuclear Information System (INIS)

Investigations were carried out of radiation level around Daya Bay for three times since the construction and operation Daya bay Nuclear Power Station and Lingao Nuclear Power Station in Guangdong province in the period of 1988 to 2000. As shown by the investigation, the radiation levels both in the field and indoors remains unchanged by and large but slightly higher than before on the roads. Also this paper gives the analysis of variations in radiation levels form site to site and from time to time. It was shown that, for environmental ? radiation levels measurements, typical measuring sites have significant impact on the meaning results. (authors)

2003-08-01

454

Strategies for catalyst development: possibilities of the ``rational approach`` illustrated with partial oxidation reactions  

Energy Technology Data Exchange (ETDEWEB)

The paper discusses two petrochemical selective oxidation reactions namely the practised formation of styrene (STY) and the desired oxidative functionalisation of propane. The present knowledge about the mode of operation of oxide catalysts is critically considered. The dehydrogenation of ethylbenzene (EB) should be described by an oxidehydration with water acting as oxidant. The potential role of the coke formed during catalytic reaction as co-catalyst will be discussed. Selective oxidation is connected with the participation of lattice oxygen mechanism which transforms unselective gas phase oxygen into selective oxygen. The atomistic description of this process is still quite unclear as well as the electron structural properties of the activated oxygen atom. The Role of solid state acidity as compared to the role of lattice oxygen is much less well investigated modern ...

1998-12-31

455

Phenol by direct hydroxylation of benzene with nitrous oxide - role of surface oxygen species in the reaction pathways  

Energy Technology Data Exchange (ETDEWEB)

Transient experiments in a Temporal Analysis of Products (TAP) Reactor were performed to elucidate the role of surface oyxgen species in the oxidation of benzene to phenol on ZSM-5 type zeolites with nitrous oxide as a selective oxidant. It was shown by puls experiments with nitrous oxide that the mean lifetime of the generated surface oxygen species is between 0.2s at 500 C and about 4.2 s at 400 C. Afterwards the surface oxygen species desorb as molecular oxygen into the gas phase where total oxidation will take place if hydrocarbons are present. Dual puls experiments consisting of a nitrous oxide puls followed by a benzene puls allowed studying the reactivity of the surface oxygen species formed during the first puls. The observation of the phenol formation was impeded due to the strong sorption of phenol. Multipulse experiments were necessary to reach a ...

1998-12-31

456

Oxygen carriers for chemical looping combustion of solid fuels  

Energy Technology Data Exchange (ETDEWEB)

A thermal analyzer-differential scanning calorimeter-mass spectrometer (TG-DSC-MS) was used to study oxygen carriers (OC) for their potential use for the application of chemical looping combustion (CLC) to solid fuels. Reaction rates, changes in reaction rates with repeated oxidation-reductions, exothermic heats during oxidation, and the effect of changing reduction gas compositions were studied. Oxidation rates were greater than reduction rates and reaction rates were reproducible through multiple oxidation-reduction cycles except where agglomeration occurred with powders. Iron oxide (Fe{sub 2}O{sub 3} powder) and iron-based catalysts were found suitable for CLC of solid fuels having rapid reduction rates which increased with higher reducing gas concentrations. Fe{sub 2}O{sub 3} powder was used to oxidize a high carbon coal char in an inert gas removing 88% of ...

2009-05-15

457

Oxidation resistance of slurry aluminides on high temperature titanium alloys  

International Nuclear Information System (INIS)

Slurry aluminizing is one method of protecting titanium alloys and intermetallics at temperatures at which oxidation would otherwise significantly degrade mechanical properties. The technique produces a continuous layer of alumina-forming TiAl_3 on exposed surfaces. The influence of composition, film thickness, and diffusion temperature upon the oxidation resistance of these slurry aluminides was studied in cyclic tests to 816degC (1500deg F). Degradation of slurry aluminized #beta#-titanium alloy and #alpha#-Z titanium aluminide intermetallic occurs by localized oxidation at cracks in the coating layer. These cracks are probably due to mismatch of coefficients of thermal expansion between the coatings and substrates. Addition of silicon to the slurry modifies the oxidation behaviour around a crack by introducing a continuous layer of titanium silicide at the boundary of the aluminide coating and ...

458

Mine drainage treatment; Kogyo haisui shori  

Energy Technology Data Exchange (ETDEWEB)

The generation of acidic mine drainage is based on the oxidation dissolution of sulfide minerals due to the contact of ores with the natural water and the air. Namely, the sulfuric acid promotes the dissolution of sulfide minerals and gangue minerals, and Fe{sup 2+} is further oxidized to turn into Fe{sup 3+}, which acts as an oxidizer for other sulfide minerals and promotes the dissolution of the same. This paper roughly describes a mine drainage treatment focusing on an Fe{sup 2+} neutralization method and an iron bacteria oxidation method. The iron bacteria oxidation method is a method of oxidizing Fe{sup 2+} into Fe{sup 3+} by using iron bacteria, and then removing Fe{sup 3+} with calcium carbonate. This method has been used for treating the drainage in the Sakuhara Mine and the former Matsuo Mine, with good results. The paper finally introduces, as ...

1996-05-25

459

Hot water extraction with in situ wet oxidation: Kinetics of PAHs removal from soil  

International Nuclear Information System (INIS)

Finding environmentally friendly and cost-effective methods to remediate soils contaminated with polycyclic aromatic hydrocarbons (PAHs) is currently a major concern of researchers. In this study, a series of small-scale semi-continuous extractions - with and without in situ wet oxidation - were performed on soils polluted with PAHs, using subcritical water (i.e. liquid water at high temperatures and pressures, but below the critical point) as the removal agent. Experiments were performed in a 300 mL reactor using an aged soil sample. To find the desorption isotherms and oxidation reaction rates, semi-continuous experiments with residence times of 1 and 2 h were performed using aged soil at 250 deg. C and hydrogen peroxide as oxidizing agent. In all combined extraction and oxidation flow experiments, PAHs in the remaining soil after the experiments were almost undetectable. In combined extraction and ...

2006-09-01

460

Effects of relative thickness of the duplex-treated layer on surface properties of AlSl H13 steel  

Energy Technology Data Exchange (ETDEWEB)

A duplex surface treatment technique based on calorizing and plasma nitriding was developed to improve the wear and oxidation resistance of H13 steel at high temperatures. The effects of the relative thickness of the calorized layer to the depth of plasma nitriding on the wear and oxidation properties at temperatures up to 900 C were investigated in this work. High-temperature wear tests were performed at 500 C with dry conditions in open air using a ball-on-disk type tribotest machine. Isothermal oxidation tests were performed at 900 C for up to 100 h under controlled atmosphere. The results indicated that the specimens with a calorized layer as an intermediate phase between the surface duplex layer and the base metal showed higher wear and oxidation resistance than the specimens with a nitrided layer alone. During exposure to elevated temperatures, the aluminum in the calorized layer diffused to the ...

1997-10-01

461

Alternate alloying for environmental resistance; Proceedings of the Symposium, New Orleans, LA, Mar. 2-6, 1986  

Energy Technology Data Exchange (ETDEWEB)

Papers are presented on the development of oxidation- and sulfidation-resistant ferritic alloys; the microstructural stability of sulfidation-resistant FeCrAl stainless steels around 500 C; age hardening in Fe-Mn-Al-C austenitic alloys; the oxidation/corrosion behavior of low-Cr Fe-Cr-Ni alloys containing Zr or Nb; the high temperature oxidation/corrosion of iron-based superalloys; and the role of Mo in the Na/sub 2/SO/sub 4/ induced corrosion of superalloys at high temperature. Topics discussed include the effect of variations of Co content on the cyclic oxidation resistance of selected Ni-base superalloys; high temperature oxidation of Fe based alloys; the morphological development of high temperature oxide scales of Fe-Mn-Al base alloys; and the oxidation of an Fe-Mn-Al-C alloy at 1000 C. Consideration is given to the corrosion properties ...

1987-01-01

462

A dynamic approach to selectivity in heterogeneous partial oxidation  

Energy Technology Data Exchange (ETDEWEB)

Despite the rapid development of literature pertaining to fundamental (1-4) studies of oxidation catalysis, a general theory of heterogeneous selective oxidation catalysis explaining the selectivity behavior of different metal oxide systems has not yet been developed. Redox mechanisms have been widely invoked in the kinetic and mechanistic descriptions of selective oxidation reactions, suggesting a dynamic behavior of hydrocarbon and oxygen interactions with the catalyst surface. Nevertheless, most of the recent theoretical approaches of this subject matter (5-7) are essentially static in nature. Correlations are made with surface structure on the basis of crystallographic considerations with selectivity being related to the nature, number, bond-strength and nearness of oxygen atoms in the neighborhood of adsorption centers. The effect of the reaction medium on the configuration of the catalyst surface, ...

1987-08-01

463

Biogenic iron oxyhydroxide formation at mid-ocean ridge hydrothermal vents: Juan de Fuca Ridge  

Energy Technology Data Exchange (ETDEWEB)

Here we examine Fe speciation within Fe-encrusted biofilms formed during 2-month seafloor incubations of sulfide mineral assemblages at the Main Endeavor Segment of the Juan de Fuca Ridge. The biofilms were distributed heterogeneously across the surface of the incubated sulfide and composed primarily of particles with a twisted stalk morphology resembling those produced by some aerobic Fe-oxidizing microorganisms. Our objectives were to determine the form of biofilm-associated Fe, and identify the sulfide minerals associated with microbial growth. We used micro-focused synchrotron-radiation X-ray fluorescence mapping (mu XRF), X-ray absorption spectroscopy (mu EXAFS), and X-ray diffraction (mu XRD) in conjunction with focused ion beam (FIB) sectioning, and highresolution transmission electron microscopy (HRTEM). The chemical and mineralogical composition of an Fe-encrusted biofilm was queried at different spatial scales, and the spatial ...

2008-05-22

464

Biological Research for Radiation Protection  

International Nuclear Information System (INIS)

The work scope of 'Biological Research for the Radiation Protection' had contained the research about ornithine decarboxylase and its controlling proteins, thioredoxin, peroxiredoxin, S-adenosymethionine decarboxylase, and glutamate decarboxylase 67KD effect on the cell death triggered ionizing radiation and H_2O_2(toxic agents). In this study, to elucidate the role of these proteins in the ionizing radiation (or H_2O_2)-induced apoptotic cell death, we utilized sensesed (or antisensed) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation and H_2O_2(or paraquat). We also investigated whether genisteine(or thiamine) may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation (may enhance the preventing effect ...

465

Investigation of Symphytum cordatum alkaloids by liquid-liquid partitioning, thin-layer chromatography and liquid chromatography-ion-trap mass spectrometry  

Energy Technology Data Exchange (ETDEWEB)

From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ionization (APCI) interface ...

2006-05-04

466

Synchrotron radiation from electron beams in plasma-focusing channels.  

Science.gov (United States)

Spontaneous radiation emitted from relativistic electrons undergoing betatron motion in a plasma-focusing channel is analyzed, and applications to plasma wake-field accelerator experiments and to the ion-channel laser (ICL) are discussed. Important similarities and differences between a free electron laser (FEL) and an ICL are delineated. It is shown that the frequency of spontaneous radiation is a strong function of the betatron strength parameter a(beta), which plays a role similar to that of the wiggler strength parameter in a conventional FEL. For a(beta) > or approximately 1, radiation is emitted in numerous harmonics. Furthermore, a(beta) is proportional to the amplitude of the betatron orbit, which varies for every electron in the beam. The radiation spectrum emitted from an electron beam is calculated by averaging the single-electron spectrum over the electron distribution. This leads to a ...

2002-05-20

467

Somatic and genetic radiation exposure of the patient in digital subtraction angiography (DSA)  

International Nuclear Information System (INIS)

The somatic and genetic radiation exposure of patients undergoing Digital Subtraction Angiography (DSA) and traditional Film Arteriography (FA) of cranial, cervical, thoracic and abdominal vascular territories are compared. The radiation doses absorbed within the critical organs - red bone marrow, lung, thyroid gland and female breast - and in the gonads were measured using an anthropomorphic Alderson phantom. A Somatic Dose Index was calculated in order to estimate the somatic radiation risk. The somatic radiation exposure depends upon the location of the critical organs with respect to the entrance site of the x-ray beam, and can be reduced by an appropriate choice of the angiographic projection. Under this condition, the radiation exposure of the patient during DSA can be lower than during FA. For renal DSA an a.p. projection, the use of an abdominal compression device and ...

1986-01-01

468

Radiation therapy in the treatment of hilar cholangiocarcinoma  

International Nuclear Information System (INIS)

The incidence of hilar cholangiocarcinoma is very rare worldwide. Radical resection is the only prognostic factor for long survival in patients with hilar cholangiocarcinoma. Postoperative radiation therapy can improve local control and survival rates for patients with palliative resection, but it remains controversial in patients with radical resection. Biliary drainage can effectively release bile duct obstruction for the majority of patients with locally advanced disease, and may even prolong survival when combined with radiation therapy. Radiation therapy includes extrernal beam therapy alone, external beam therapy with intraluminal brachytheapy and new radiation technique, such as three dimentional conformal therapy and intensity modulated radiation therapy. The propective randomized clinical study is needed for further investigation in the role of combined modality therapy ...

2007-10-01

469

Radiation receiver. Strahlungsempfaenger  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the invention is to improve a radiation receiver, consisting of a hollow body with an opening for the entry of radiation and a ceramic absorber situated in the hollow body, which absorbs the radiation energy entering through the opening, and emits it as thermal radiation to a heat medium, so that a higher efficiency can be achieved. According to the invention, the problem is solved by the fact that the absorber consists of ceramic material on the side towards the solar radiation, which has a low emission value and a high absorption value, and that the side of the absorber towards the heat medium has ceramic material of high emission value and low absorption value. This ensures that reradiation is prevented near the opening of the hollow body, and that the solar energy entering is largely absorbed in the hollow body.

1981-10-01

470

Procedure for radiation dose control in irradiated tissues during electron-beam therapy  

International Nuclear Information System (INIS)

The invention refers a procedure of radiation dose control in irradiated tissues during electron-beam therapy. It aims at meeting the planned radiation dose for diseased tissues and taking care of the healthy ones. Therefore, the dose distribution required is determined before irradiation in consideration of such factors as energy-dependence of detector sensitivity, self-absorption within the tissue, and relative biological effectiveness. Furthermore, the expected intensity distribution of secondary quantum radiation excited in the irradiated tissue is calculated. A radiation detector for local resolution is used for registration. During irradiation the calculated intensity distribution is compared with the measured one. The invention is applicable in radiation therapy with monoenergetic electron beams.

1984-11-08

471

Ionizing radiation effect on sealant properties  

International Nuclear Information System (INIS)

Presented are the investigation results of electrophysical and physico-mechanical properties of KLF-20, Viksint U-4-21, Viksint KT-73, UF-7-21, KG-184, KL-4, KL-16SE-305, VIAT-1 and PPK-21 sealants, irradiated with sources of continuous and pulse #gamma#-radiation, as well as pulse #gamma#-neutron radiation. It is shown that electrophysical and physico-mechanical properties of sealants after irradiation by continuous #gamma#-radiation up to 10"6 doses and pulse gamma-neutron radiation with neutron fluence of 10"1"3 neutron/cm"2 and #gamma#-radiation dose of 10"4R do not practically change. Electric conductivity and tangent of the angle of dielectric losses increase in the process of irradiation. Electric conductivity depends on irradiation type, is proportional to dose rate and does not depend on temperature and pulse duration.

472

Compare analysis of efficiency of using of digital and analog regimes of registration of radiation in radiometric systems of radiation thickness measuring  

International Nuclear Information System (INIS)

A consideration is given to the problem of selecting optimized methods of radionuclide radiation registration during the control of the objects with essential changes in thickness. Adequate model of information signal formation is developed and analyzed for the case of the existence of an inertial link of the system with the dead time of a noncontinued type. The boundary values of radiation thickness and radiation flux intensity that divide the priority of using either digital or analog registration modes are revealed. The method is found for the full correction of a systematic error of flux intensity measurement because of the dead time of the apparatus. To control the objects with essential variation of thickness the method of selective measurement of radiation intensity is proposed

473

Packaging materials for use in radiation processing of foods  

International Nuclear Information System (INIS)

In radiation processing of food, the product often has to be prepackaged to prevent microbial recontamination during and after irradiation. The packaging material is exposed to radiation during radiation processing and radiation stability is a key consideration in the selection of packaging materials. The effects of ionizing radiation on many food packaging materials at the dose levels recommended for food precessing can be minimized by selecting appropriate radiation resistant materials. It is important to select materials in which chemicals formed as a result of the radiation treatment do not migrate and interact with the food, affecting its organoleptic and toxicological aspects. It is also important to select materials in which the physical properties are not altered to the extent they cannot resist damage during commercial production, ...

474

Method and system for determining depth distribution of radiation-emitting material located in a source medium and radiation detector system for use therein  

Energy Technology Data Exchange (ETDEWEB)

A method, system and a radiation detector system for use therein are provided for determining the depth distribution of radiation-emitting material distributed in a source medium, such as a contaminated field, without the need to take samples, such as extensive soil samples, to determine the depth distribution. The system includes a portable detector assembly with an x-ray or gamma-ray detector having a detector axis for detecting the emitted radiation. The radiation may be naturally-emitted by the material, such as gamma-ray-emitting radionuclides, or emitted when the material is struck by other radiation. The assembly also includes a hollow collimator in which the detector is positioned. The collimator causes the emitted radiation to bend toward the detector as rays parallel to the detector axis of the detector. The collimator may be a hollow cylinder ...

2003-03-04

475

V{sub 2}O{sub 5}-ZrO{sub 2} catalysts for the oxidative dehydrogenation of propane - influence of the niobium oxide doping  

Energy Technology Data Exchange (ETDEWEB)

The oxidative dehydrogenation (ODH) of light alkanes is an alternative way for the production of olefins. A wide variety of catalytic systems has been investigated. Vanadium oxide based catalysts were described in the literature as effective catalysts for the ODH of propane. The catalytic activity and selectivity depend on the kind of support material, the kind of dopants and the formation of complex metal oxide phases. In recent papers it was claimed that both orthovanadate and/or pyrovanadate species are selective for the ODH of propane. Niobia based materials were investigated as catalysts for acidic and selective oxidation type reactions. In the ODH of propane niobia exhibited a high selectivity to propene but the conversion of propane was low. V{sub 2}O{sub 5}-Nb{sub 2}O{sub 5} catalysts proved to be catalytically active and selective and showed no formation of oxygenates. In the present study the ...

1998-12-31

476

Treatment of a waste salt delivered from an electrorefining process by an oxidative precipitation of the rare earth elements  

Energy Technology Data Exchange (ETDEWEB)

For the reuse of a waste salt from an electrorefining process of a spent oxide fuel, a separation of rare earth elements by an oxidative precipitation in a LiCl-KCl molten salt was tested without using precipitate agents. From the results obtained from the thermochemical calculations by HSC Chemistry software, the most stable rare earth compounds in the oxygen-used rare earth chlorides system were oxychlorides (EuOCl, NdOCl, PrOCl) and oxides (CeO{sub 2}, PrO{sub 2}), which coincide well with results of the Gibbs free energy of the reaction. In this study, similar to the thermochemical results, regardless of the sparging time and molten salt temperature, oxychlorides and oxides were formed as a precipitant by a reaction with oxygen. The structure of the rare earth precipitates was divided into two shapes: small cubic (oxide) and large plate-like (tetragonal) structures. The ...

2009-02-28

477

Treatment of a waste salt delivered from an electrorefining process by an oxidative precipitation of the rare earth elements  

International Nuclear Information System (INIS)

For the reuse of a waste salt from an electrorefining process of a spent oxide fuel, a separation of rare earth elements by an oxidative precipitation in a LiCl-KCl molten salt was tested without using precipitate agents. From the results obtained from the thermochemical calculations by HSC Chemistry software, the most stable rare earth compounds in the oxygen-used rare earth chlorides system were oxychlorides (EuOCl, NdOCl, PrOCl) and oxides (CeO2, PrO2), which coincide well with results of the Gibbs free energy of the reaction. In this study, similar to the thermochemical results, regardless of the sparging time and molten salt temperature, oxychlorides and oxides were formed as a precipitant by a reaction with oxygen. The structure of the rare earth precipitates was divided into two shapes: small cubic (oxide) and large plate-like (tetragonal) structures. The conversion ...

2009-02-28

478

The corrosion resistance of alloy 800  

International Nuclear Information System (INIS)

Basic studies of the oxidation resistance of Fe-Cr binary and Fe-Cr-Ni ternary alloys in pure oxygen have shown that the excellent corrosion resistance of Alloy 800 is explicable in terms of the low defect concentrations and diffusion rates in the oxide forming on alloys of this composition in sufficiently oxidising environments. The performance of Alloy 800 in environments of particular importance to nuclear power generation is briefly reviewed to determine to what extent ideas derived from the basic studies of Fe-Cr-Ni ternary alloys are borne out in practice. The good corrosion resistance of Alloy 800 in steam and CO_2 and, to some extent, in molten salt environments is in agreement with the behaviour of ternary alloys in oxygen. Minor aliovalent alloying additions are only expected to have a significant effect on the oxidation resistance of Alloy 800 if they favour the formation of breakthrough duplex ...

479

Session 6: Effect of Zeolite Supported Catalysts on the Decomposition of Pyridine  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to test the catalytic oxidation of pyridine over zeolite-supported catalysts and to compare the difference in their activities for the oxidation of pyridine. The catalytic oxidation of pyridine pollutant on a series of copper-supported catalysts, inclusive of Cu/beta, Cu/ZSM-5, Cu/MCM-41 and Cu/{gamma}-Al{sub 2}O{sub 3}, in the presence of excess oxygen was studied. The activity of the copper-supported catalysts for the pyridine oxidation could be correlated with the binding energy of oxygen coordinated to metal copper, while the ability to control the yield of NO{sub x} appeared to be strongly dependent on the binding energy of NO bonded to metal copper. On these catalysts, two copper species, Cu(H{sub 2}O){sub 6}{sup 2+} ions and CuO were identified, in which Cu{sup 2+} ions had higher activity for the NO{sub x} control but poorer activity for the pyridine ...

2004-07-01

480

Plasma onditions for nitriding a stainless steel. Report 2. Fundamental study of ion-nitriding by D. C. glow discharge. Stainless ko no chikka tassei no tameno purazuma keitai. 2. Chokuryu guro hoden wo mochiita ion chikka purosesu ni kansuru kisoteki kenkyu  

Energy Technology Data Exchange (ETDEWEB)

Dominating factors in plasma nitriding and plasma condition that makes nitriding possible in plasma nitriding process of metals having hard oxide film were studied. In case of stainless steel, oxide film sputtering was easier comparing to nitriding layer. Three phenomena such as sputtering of oxide layer, formation of nitriding layer and sputtering of nitriding layer occurred simultaneously. Nitriding was achieved when the formation of nitriding layer reached the peak comparing to the removal of nitriding layer after the removal of oxide layer. Situations of metallic surface of stainless steel in surface nitriding were divided into four categories and they were, situation where oxide layer remained as it is, situation where nitriding layer was formed although oxide layer remained in some part, situation where only nitriding layer was formed and situation where ...

1994-05-05

481

Oxidative dehydrogenation of ethane on rare-earth oxide-based catalysts  

Energy Technology Data Exchange (ETDEWEB)

Results on the oxidative dehydrogenation of ethane on rare-earth oxide (REO) based catalysts (Na-P-Sm-O, Sm-Sr(Ca)-O, La-Sr-O and Nd-Sr-O) are described. Oxygen adsorption was found to be a key factor which determines the activity of this type of catalysts. Continuous flow experiments in the presence of catalysts which reveal strong oxygen adsorption showed that the reaction mixture is ignited resulting in an enhanced heat generation at the reactor inlet. The heat produced by the oxidative reactions was sufficient under the conditions chosen for the endothermic thermal pyrolysis which takes place preferentially in the gas phase. Ignition of the reaction mixture is an important catalyst function. Contrary to non-catalytic oxidative dehydrogenation, reaction temperatures above 700 C could be achieved without significant external heat input. Ethylene yields of up to 34-45% (S=66-73%) were obtained on ...

1998-12-31

482

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system.  

Science.gov (United States)

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. ...

2007-01-01

483

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO_2 films  

International Nuclear Information System (INIS)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to ...

484

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO[sub 2] films  

Energy Technology Data Exchange (ETDEWEB)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to ...

1993-07-16

485

Conversion of a plasma enhanced chemical vapor deposited silicon-carbon-nitride thin film at ultra-low temperature by oxygen plasma  

Energy Technology Data Exchange (ETDEWEB)

In this work we present an ultra-low temperature method for the oxidation of an amorphous silicon-carbide-nitride (SiCN) material. The SiCN is deposited on silicon substrates by plasma enhanced chemical vapor deposition using CH{sub 4}, SiH{sub 4}, and N{sub 2} chemistry. The physical and chemical properties are characterized for the as-deposited SiCN and post-oxidized films are discussed. The SiCN film is exposed to oxygen plasma, where it undergoes a chemical transformation into a binary SiO{sub 2} material system. A 1.7 nm/min oxidation rate is typical for this process and compares favorably to oxidation methods utilizing much higher temperatures. The substrate temperature remains extremely low throughout the oxidation process, T{sub s} < 200 deg. C. Changes in film stress, optical constants, film thickness, surface roughness, and film density are measured. Chemical ...

2008-01-30

486

The adsorption and reaction of halogenated volatile organic compounds (VOC's) on metal oxides. Annual progress report, September 1996--October 1997  

Energy Technology Data Exchange (ETDEWEB)

'The interactions of carbon tetrachloride with strongly basic oxides and hydroxides have been studied by several techniques in order to understand the surface reactions and the subsequent bulk reactions that result in the destruction of the chlorinated hydrocarbon. Emphasis has been placed on understanding the surface phases, as well as the bulk phases, that are present during these transformations. As a result of the study with barium oxide, a reaction cycle has been demonstrated that may have practical significance in the removal of chlorinated hydrocarbons.'

1997-10-01

487

Protective oxides in coal-fired combined cycle power systems  

Energy Technology Data Exchange (ETDEWEB)

In most industrial processes operating at elevated temperatures, protective oxide layers perform a vital duty in protecting the underlying metallic alloys from process gases. Coal-fired combined cycle power generation systems present a number of process conditions in which the properties of the protective oxide layers are particularly important. This paper discusses two of these particular conditions: (1) `erosion/corrosion` of in-bed heat exchanger tubing and (2) thermal cycling of hot gas path components. For both these situations, the desirable properties of protective scales are outlined. The behaviour of scales in practice are highlighted. 33 refs., 6 figs., 2 tabs.

1995-12-31

488

One-electron oxidation of photosynthetic pigments in micelles. Bacteriochlorophyll a, chlorophyll a, chlorophyll b, and pheophytin a  

International Nuclear Information System (INIS)

Chlorophyll a, chlorophyll b, and bacteriochlorophyll a in aqueous micellar solutions of Trition X 100 (2%) are readily oxidized by pulse-radiolytically generated N_3., Br_2"-., and (SCN)_2"-. radicals at nearly diffusion-controlled rates. The kinetic study suggests that pigment molecules occupy multiple sites in the micelle. Pheophytin a is only oxidized by N_3. and Br_2"-. radicals. The absolute spectra and the molar extinction coefficients of chlorophyll a, bacteriochlorophyll a, chlorophyll b, and pheophytin a cations have been determined. The chlorophyll a cation has been observed in the presence of pigment aggregates.

1981-11-01

489

On the catalytic gas phase oxidation of butadiene to furan  

Energy Technology Data Exchange (ETDEWEB)

Applying the thermochemical selectivity criterion of Hadnett et al. It is shown that the selectivity of the furan formation is not limited by a too low strength of the C-H bonds in furan when compared with the C-H bond dissociation energy in the educt molecule butadiene. In the oxidation of butadiene on a CsH{sub 2}PMo{sub 12}O{sub 40} catalyst a maximum yield of 22 mol% furan has been obtained. To improve this comparatively low furan yield oxidation activity of the catalyst must be lowered to prevent the consecutive reaction to maleic anhydride. (orig.)

1998-12-31

490

Nitrogen oxides decreasing combustion method  

Energy Technology Data Exchange (ETDEWEB)

A nitrogen oxides decreasing combustion method comprising: mixing a fuel and air with each other; bringing the mixture obtained into contact with a packed catalyst; and adding a fresh supply of the fuel to the stream obtained to form a mixed gas and causing the mixed gas to undergo non-catalytic thermal combustion, characterized in that only a catalytic reaction or combustion occurs at the packed catalyst; the temperature of the packed catalyst is kept lower than the ignition temperature of the mixture; the adiabatic flame temperature which is reached by the non-catalytic thermal combustion of the mixed gas is lower than the temperature at which the nitrogen oxides occur. 39 figs.

1988-10-19

491

Nitrogen oxides decreasing combustion method  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a nitrogen oxides decreasing combustion method which comprises: a first step of mixing a fuel and air with each other; a second step of bringing the mixture obtained in the first step into contact with a packed catalyst such that only catalytic combustion occurs; and a third step of adding a fresh supply of the fuel to a stream obtained from the second step to form a mixed gas and causing the mixed gas to undergo non-catalytic thermal combustion. The temperature of the packed catalyst is lower than the ignition temperature of the mixture and the adiabatic flame temperature of the mixed gas is lower than a temperature at which the nitrogen oxides occur.

1988-03-22

492

Molecular models in the quantum-chemical investigation of the structure of defect centers on oxide catalysts  

Energy Technology Data Exchange (ETDEWEB)

Several possibilities of the use of molecular models in quantum-chemical investigations of the structure of defect centers on the surfaces of oxides on nontransition elements have been illustrated. There has been a special discussion of the assumption of the local nature of the chemical interactions in these systems, which underlies such an approach, and of the consequent laws governing the formation of their lattices in the example cases of zeolites, kaolinites, and comparable boron- and aluminum-containing oxides. A quantum-chemical interpretation of the body of experimental data from investigations of the dehydroxylation of H forms of zeolites has been given. The structure of the Lewis acid centers formed as a result, and their chemisorption properties, have been discussed.

1987-05-01

493

Mechanisms of Alloy 800 corrosion in helium  

International Nuclear Information System (INIS)

Cr_2O_3 scales are found to form on Alloy 800 and a similar pure ternary alloy in air, and 1 and 50 atm. helium containing oxidizing impurities typical of those in an SGHTR. The strong temperature dependence and neglibible helium overpressure dependence indicate that gas transport through the scales is not rate controlling. Surface oxidation rates are therefore controlled by solid state diffusion and the low oxygen partial pressure dependence of the oxidation rate in Alloy 800 is ascribed to the presence of extrinsic defects in the Cr_3O_3 (due to doping by alloying elements) or to the presence of short circuit diffusion paths. (Auth.).

494

Luminescent lanthanide-ion doped nanoparticles as single-biomolecule labels and oxidant sensors  

Science.gov (United States)

We report on the single-particle properties of lanthanide-ion doped oxide nanoparticles. We have demonstrated that their size can be accurately determined from their luminosity. The optically determined size distribution is in very good agreement with the distribution obtained from transmission electron microscopy (TEM). We also showed that the photobleaching of these nanoparticles is related to a reduction process and that we can use it to sense in a concentration-dependent manner the presence of an oxidant like H2O2. Finally, we propose a way to perform nanoparticle-protein coupling and to determine the protein-nanoparticle ratio at the single-particle level.

2007-02-01

495

Kinetics of reduction of iron oxides using microwaves as power source  

Energy Technology Data Exchange (ETDEWEB)

This work deals with kinetic description of carbothermic reduction of iron oxides using microwaves as power source. Previous researches show that it is possible to conduct this kind of process successfully, but real kinetic comparisons between conventional and microwaves procedure have been presented partially. The aim of this work is to describe reduction kinetics, taking into account how the iron oxide is reduced by microwaves compared with conventional energy supply. In this study the authors used iron ore in pellet shape and dust. They found that both, pellet and dust reduction stops when it reaches approximately 40%, even at whole power.

1996-12-31

496

Functionalized luminescent oxide nanoparticles for sodium channel imaging at the single molecule level  

Science.gov (United States)

Lanthanide-ion doped oxide nanoparticles were functionalized for use as fluorescent biological labels. These nanoparticles are synthesized directly in water which facilitates their functionalization, and are very photostable without emission intermittency. Nanoparticles functionalized with guanidinium groups act as artificial toxins and specifically target sodium channels. They are individually detectable in cardiac myocytes, revealing a heterogeneous distribution of sodium channels. Functionalized oxide nanoparticles appear as a novel tool particularly well adapted to long-term single-molecule tracking.

2005-04-01

497

Chromatographic separation of lithium isotopes by hydrous manganese(IV) oxide  

Energy Technology Data Exchange (ETDEWEB)

Separation of lithium isotopes was investigated by chemical ion exchange with a hydrous manganese(IV) oxide ion exchanger using an elution chromatography. The capacity of manganese(IV) oxide ion exchanger was 0.5 meq/g. The heavier lithium isotope was enriched in the solution phase, while the lighter isotope was enriched in the ion exchanger phase. The separation factor was determined according to the method of Glueckauf from the elution curve and isotopic assays. The separation factor of {sup 6}Li{sup +} -{sup 7}Li{sup +} isotope pair fractionation was 1.018.

2001-06-01

498

Chemical aspects of uranium behavior in soils: A review  

British Library Electronic Table of Contents (United Kingdom)

Uranium has varying degrees of oxidation (+4 and +6) and is responsive to changes in the redox potential of the environment. It is deposited at the reduction barrier with the participation of biota and at the sorption barrier under oxidative conditions. Iron (hydr)oxides are the strongest sorbents of uranium. Uranium, being an element of medium biological absorption, can accumulate (relative to thorium) in the humus horizons of some soils. The high content of uranium in uncontaminated soils is most frequently inherited from the parent rocks in the regions of positive U anomalies: in the soils developed on oil shales and in the marginal zone of bogs at the reduction barrier. The development of nuclear and coal-fired power engineering resulted in the environmental contamination with uranium....

2011-01-01

499

A study of crystalline and stress behavior in oxide films prepared by ion assisted deposition  

International Nuclear Information System (INIS)

One of the main problems related to optical thin film materials used in high power laser environments is the catastrophic damage caused to them due to laser irradiation. While the influence of ion bombardment on the optical properties of oxide thin films is now a well understood subject, the morphology and crystalline behaviour of these films under ion incidence is not so well studied. Hence, it is of great importance to investigate the effects of ion bombardment during growth on the microstructure and crystalline behaviour of oxide materials.

1994-10-24

500

X-ray dose enhancement effects  

International Nuclear Information System (INIS)

A brief description of the physical process of dose enhancement effects produced by X-ray radiation on materials is given, with emphasis on the influence on electronic devices. The damages caused by X-ray radiation dose enhancement is more serious than that of #gamma#-ray with higher energy.