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 ...

KoreaScience (Korea)

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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.

International Nuclear Information System (INIS)

The use of finely powdered ion exchange resins improve loading of specific ion exchange materials with better performance but as such these materials are not suitable for column operation. However, by proper selection of ion exchange support medium, it is possible to get better product. The radioactive solution can be treated by suspending this material, stirring and allowing to settle. The present method gives DF in the range of 70 - 80 even after repeated use as compared to DF in the range of 5 to 10 by single conventional chemical treatment process. (author)

International Nuclear Information System (INIS)

Russian (Jan 1978). USSR Chorna, IM Beshta, EI Kvitkovskij, LN L'vovskij

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Binding of Cd/sup 2 +/ ions in aqueous solutions of statistical copolymers of acrylamide with cadmium acrylate with different content of ionogenic groups in copolymers was investigated by polarography, conductometry, viscometry and dialysis. It is shown that the degree of binding of Cd/sup 2 +/ ions increases with increasing of the content of ionogenic groups in the copolymer and with decreasing of ionic strength of the solution. The values of the degree of binding of Cd/sup 2 +/ ions obtained by polarography and dialysis show satisfactory agreement.

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

A method has been developed for the adsorption of Sc"I"I"I employing inorganic ion exchanger zirconium phosphosilicate by batch method. Effects of various parameters have been evaluated on the percentage adsorption of Sc"I"I"I. Separation of Sc"I"I"I from various other elements is standardized. (author)

Energy Technology Data Exchange (ETDEWEB)

In this report, the quantitative relation between the height equivalent to a theoretical plate (HETP) and the size of ion exchange resin is studied by enriching lithium isotopes with high pressure ion exchange displacement chromatography. The dependence of HETP on the size of the resin can be expressed as H = C x (anti r)sup( ) in which = 2.4 and it is found that Snyder's equation is suitable for such a system of isotope separation as may be explained by the simple displacement mechanism.

Energy Technology Data Exchange (ETDEWEB)

Cited are the results of physico-chemical studies and industrial tests of a copolymer of methacrylic acid and diethylammonium salt, used for limiting the influx of stratum waters into a well.

Science.gov (United States)

In: Geology and Seismic Stratigraphy of the Antarctic Margin, Antarctic Research Series vol. 68, edited by A.K. Cooper, P.F. Barker and G. Brancolini, ...

International Nuclear Information System (INIS)

The synthetic process of polyethylene cation exchange capillary via radiation grafting polystyrene by simultaneous irradiation with "6"0Co #gamma#-ray source and sulfonation with concentrated H_2SO_4 was studied. The effects of dose, dose rate, monomer concentration, solvents, temperature and crosslinking agents on the graft copolymerization of styrene with polyethylene capillary were illustrated. The relationship between the radiation grafting conditions and the properties of ion-exchange capillary were examined. A polyethylene cation exchange capillary with I.D. 0.8 mm, length 20 m, exchange capacity 0.7 Meq/g 60% capacity in 10 s (flow rate 20 ml/min) was prepared. No significant loss of copacity was found from this ion-exchange capillary after 200 adsorption/regeneration cycles.

International Nuclear Information System (INIS)

Liquid radioactive waste treatment method of using evaporator was widely used from Kori 1 to Uljin 3 and 4, but a liquid radioactive waste treatment equipment that uses an ion exchange method instead of an evaporator was adopted aiming to minimize amount of radioactive waste and radiation exposure. However, the same equipment was introduced and applied for the first time in Korea and had experienced difficulties in securing credibility for the equipment and handling of liquid radioactive waste with inadequate data about performance and experience in operation and maintenance. In this study, examination, application and effect analysis was performed on the optimization measure for handling liquid radioactive waste of Yonggwang Nuclear Power Unit 5 and 6(YGN 5 and 6) that applies an ion exchange method

International Nuclear Information System (INIS)

A Process for yellow cake production from local Euxenite was developed in Bench Scale by using sulphuric acid digestion with simultaneously ion-exchange and solvent extraction purification steps. Uranium was then precipitated as uranium diuranate by ammonia solution. Equipment used in this process includes : digestion vessels, columnar ion-exchange, solvent extraction and precipitation units Ore feed to the process could be adjusted up to 2 kilogram per day (8 hours operation) with yellow cake product purity meet the requirement of Usaec standard of about 10-50 gram per day. Included in this experiment are the leaching characteristics of the ore, the design and construction of continuous columnar 4-cycle ion exchange unit, determination of the extraction and stripping stages of a gravity flow mixer-settler and the design and construction of continuous yellow cake precipitation unit with large grain size ...

Energy Technology Data Exchange (ETDEWEB)

A series of N-carbazolyl-substituted silane homo- and copolymers has been prepared by Wurtz coupling. Doping with iodine on these copolymer films increases the electrical conductivity to the range 10{sup -6}-10{sup -3} S cm{sup -1}. The conductivity depends strongly on the composition of the copolymer; it reaches the maximum value for N-carbazolyl-substituted silane homopolymer. The effects of carbazolyl group on conductivity and charge transport mechanisms in the polymer are discussed. (orig.)

UK PubMed Central (United Kingdom)

Antibodies of the IgM type present in rabbit anti-epiglycanin antiserum were purified by (NH4)2SO4 precipitation and by ion-exchange, affinity and gel-filtration chromatography. After papain treatment...Full Text Available

UK PubMed Central (United Kingdom)

The aim of the present study was to describe the physicochemical characteristics of streptococcal T antigen. T protein isolated from Streptococcus pyogenes type 12 (R53/1077, Colindale) and purified...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

This paper presents the corrosion inhibition performance of soluble self-doped copolymers of aniline and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid synthesized by chemical oxidative polymerization method. The corrosion inhibition behaviour of the copolymers in 1.0M HCl has been evaluated using Tafel Extrapolation method and electrochemical impedance spectroscopy (EIS) which was also used to propose the mechanism besides surface morphology. The results showed that the copolymer film exhibited the significant shifting in the corrosion potential and greater charge transfer resistance. The corrosion inhibition efficiency was found to increase from 50% to 90% by increasing the concentration of copolymer from 10 to 70mg/l in HCl medium. Moreover, the copolymer showed the larger degree of surf...

International Nuclear Information System (INIS)

Recovery of uranium by ion-exchange processes from impure acid leach liquors is described, which produce a concentrated and pure eluate employing 10% sulphuric acid elution. In situations where resin is loaded to 45 g/ltr or more the acid consumption at ambient temperature is less than 4 kg of H_2SO_4 per kilogram of U_3O_8. Precipitation with an alkali such as ammonia or magnesia produces a yellow cake of high purity. (author).

Energy Technology Data Exchange (ETDEWEB)

A series of copolymers based on the cellulose acetate/propionate-g.co-acrylic acid system has been prepared under radiation-induced control. These copolymers have been assessed for their water-retention capacity both in an unmodified state and after ''decrystallization'' or ''neutralization'' treatments. The grafting of acrylic acid onto the cellulose acetate/propionate had little effect on the water retention power of the cellulose acetate/propionate. However, improvements to the water retentivity was obtained after ''decrystallization'' procedures had been carried out on the copolymers using selected alkali metal salts with methanol as the continuous medium. The water-retentivity of the copolymers increased with increase in the extent of grafting, though the effect is less pronounced at high ...

International Nuclear Information System (INIS)

Nanowires of copolymers film based on aniline and 1-amino-2-naphthol-4-sulphonic acid were electrochemically synthesized on the iron electrode by cyclic voltammetry using oxalic acid as a supporting electrolyte. Protective properties of copolymer film on the iron surface in 1.0 M HCl solution was investigated by chronoamperometry, potentiodynamic polarization technique and electrochemical impedance spectroscopy (EIS). The results showed that the copolymer film showed the significant shifting in the corrosion potential and greater charge transfer resistance. Moreover, the copolymer showed the larger degree of surface coverage onto the iron surface, reflecting the higher protection for corrosion of the iron in acidic medium. In addition, the film constitutes a physical as well as a chemical barrier layer due to the presence of -OH and -NH groups in ANSA unit, which provides passivity protection in polymer ...

International Nuclear Information System (INIS)

We have successfully incorporated high surface area particles of titanate ion exchange materials (monosodium titanate and crystalline silicotitanate) with acceptable particle size distribution into porous and inert support membrane fibrils consisting of polytetrafluoroethylene (Teflon(reg_sign)), polyethylene and cellulose materials. The resulting membrane sheets, under laboratory conditions, were used to evaluate the removal of surrogate radioactive materials for cesium-137 and strontium-90 from high caustic nuclear waste simulants. These membrane supports met the nominal requirement for nonchemical interaction with the embedded ion exchange materials and were porous enough to allow sufficient liquid flow. Some of this 47-mm size stamped out prototype titanium impregnated ion exchange membrane discs was found to remove more than 96% of dissolved cesium-133 and ...

British Library Electronic Table of Contents (United Kingdom)

Poly(methyl methacrylate), PMMA, scrap generated during the casting process for PMMA cast sheet is an industrial waste stream, which has a high impact on the PMMA production cost and environment. This paper presents an alternative way to reduce the processing cost of PMMA cast sheet and decrease industrial waste by using styrene (S) as a co-monomer with methyl methacrylate (MMA) monomer, in conjunction with recycling of PMMA scrap in the S-MMA copolymer cast sheet process. The influence of factors, such as the concentrations of S and PMMA scrap, on the preparation of S-MMA copolymer cast sheet mixed with PMMA scrap was investigated. The characterization of basic copolymer composition, the physical, and the mechanical properties of the final products were examined. The results show that it ...

Science.gov (United States)

Five cycles of loading, elution, and regeneration were performed to remove technetium from a Hanford waste sample retrieved from Tank 241-AW-101 using SuperLig 639 resin. The waste sample was diluted to 4.95 M Na plus and then was processed to remove 137Cs through dual ion exchange columns each containing 15 mL of SuperLig 644. To remove 99Tc, the cesium decontaminated solution was processed downwards through two ion exchange columns, each containing 12 mL of SuperLig 639 resin. The columns, designated as lead and lag, each had an inside diameter of 1.45 cm and a height of 30 cm. The columns were loaded in series, but were eluted and then regenerated separately. The average technetium loading for the cycles was 250 BV at 10 percent breakthrough. There was no significant difference in the loading performances among the five cycles. The percent removal of 99Tc was greater than 99.94 percent and the ...

Energy Technology Data Exchange (ETDEWEB)

It is needless to say that one of the most important roles of the condensate demineralizer in Japanese boiling water reactors (BWR) is to eliminate such impurities during accidental occurrence of sea water leakage from condensate cooling system. Ion exchange resins packed in condensate demineralizer have also been expected to decrease crud, or corrosion products (CP) in condensate water in order to finally reduce activated corrosion products (ACP) in the reactor coolant loop. It is perceived that crud removal ability of a condensate demineralizer has been improved year by year. And we call this phenomenon as `Aging Effect`. Typical property changes of aged cation exchange resin consisted of an increase of water retention capacity and a change of surface texture. Based on these findings, we formulated a new concept and developed new gel type ion exchange resins for the better crud removal. The results ...

International Nuclear Information System (INIS)

Using electrochemical techniques of pH-metry and conductimetry, the choice of a suitable complexing reagent was made amongst ethylene glycol, propylene glycol, dextrose and mannitol for cost-effective separation of isotopes of boron by ion exchange chromatography. Quantitative relationships between pH and concentration; pK_a and concentration of each of these complexing reagents were determined by least square polynomial curve fitting and an attempt was made to determine the formation constants of mannitol-borate complex. The results of experiments carried out for selection; regeneration of a resin; separation factor determinations using batch as well as column techniques and monitoring of band movements using these electrochemical techniques are discussed. (author).

International Nuclear Information System (INIS)

Novel and unprecedented ion exchange resin cleaning system, for use in BWR plants and featuring a vibration separator and basic design factors of Radiological Solutions, Inc., had been delivered to Tokai No. 2 Power Station, Japan Atomic Power Company, in October 2005. This compactly-designed system effectively separates crud and resin fines from ion exchange resins, with no clogging of separation screens. It generates minimized waste liquid and has a specially designed over-pack cleaning tank. The system has been in operation for about 2 years and half now and favorable operational data, such as crud and sulfate concentration decrease in feed water and reactor water respectively, and evaluation results have been reported from Japan Atomic Power Company and so on. (author)

Science.gov (United States)

Copolymers of a 1,2 epoxy alkane and a cyclic carboxylate compound of the class consisting of dicarboxylic acid anhydrides, preferably maleic anhydride or a hydrocarbyl substituted succinic anhydride and a beta lactone, said copolymers having C/sub 10/ to C/sub 50/, preferably C/sub 20/ to C/sub 40/, linear, pendant hydrocarbon chains are flow improvers in residual and crude oils.

Energy Technology Data Exchange (ETDEWEB)

Research at the Savannah River Technology Center aided development of a technical design basis for a Waste Treatment Plant (WTP) to pre-treat and vitrify Hanford tank waste as part of the River Protection Project (RPP). The research addresses safety concerns, process optimization, and waste form compliance. This program will provide technical data to ensure that the process functions as it was designed and minimizes costs.

International Nuclear Information System (INIS)

Determination of Cr, Fe, Cu, Zn and Pb in drinking water preconcentrated on a chelating ion exchanger of Czechoslovak production is described. The analytical system consisted of a radionuclide source "2"3"8Pu, a Si/Li semiconductor detector and a multichannel analyzer. Results are compared with trehshold limit values recommended for drinking water. (author) 9 refs.; 2 figs.

International Nuclear Information System (INIS)

Gadolinium nitrate has been employed in Indian nuclear reactors for the first time as soluble neutron poison in the heavy water moderators of the 540 MWe PHWRs TAPS 3 and 4, as a fast acting secondary shut down system (SDS-2); and also for reactivity shim. For this purpose, the moderator purification system is currently equipped with special ion-exchange columns/schemes, developed by present authors. However, for gadolinium removal from moderator in the post SDS-2 scenario, the two stage ion-exchange - cation bed operation followed by mixed bed operation - results in low pH conditions persisting in the moderator for a few hours, which gives rise to certain operational problems. The present paper describes a mixed bed ion-exchange scheme employing macro-porous strong acid cation and macro-porous weak base anion resins, which has been developed to eliminate acidic conditions and gives a better pH control. The cation to anion ...

International Nuclear Information System (INIS)

The formation of astatide-mercury complexes was investigated in aqueous solutions.The obtained complexes were examined by paper electrophoresis. It was found that Hg(OH)At and Hg(OH)I complexes were formed in neutral solution. The stability constants of the obtained complexes were determined by ion-exchange. The preliminary results indicate that the complex of mercury with astatide is much more stable than similar complexes with iodide. (author)

British Library Electronic Table of Contents (United Kingdom)

An amphiphilic azobenzene diblock copolymer {2-[4-(4-methoxy phenyl azo)phenoxy]hexyl acrylate co-acrylic acid} was synthesized via reversible addition-fragmentation chain transfer polymerization in a hydrothermal reactor. The products were characterized by 1H-NMR, DSC, GPC and UV-Vis spectroscopy. Different self-assembly behaviors of this amphiphilic diblock copolymer in different organic solvent with different water content were investigated. In THF/H2O solution, the diblock copolymer self-assembled into spheres and the spheres would then change to vesicles with smaller size by increasing the volume of H2O. However, in DMSO/H2O solution, the sizes and morphologies of the self-assembled spheres would not change significantly with an enhanced amount of H2O. Photochromic behaviors of the am...

British Library Electronic Table of Contents (United Kingdom)

The chloromethylation reaction of an asphaltite and styrene graft copolymer followed by the amination of the chloromethylated products was optimized. New strongly basic anion exchangers with an exchange capacity of 2.5 mg-equiv/g and a mechanical strength of 93% were prepared.

Energy Technology Data Exchange (ETDEWEB)

This paper studies the sorption of chlorine complexes of ruthenium (IV) on the graft copolymer of a polyacrylonitrile fiber with poly-2-methyl-5-vinylpyridine (PAN-MVP). The composition of the fiber is illustrated. It is shown that sorption of chlorine complexes of ruthenium (IV) from acid solutions by a pyridine fiber sorbent takes place according to an anion-exchange mechanism and is due to the formation of compounds of the diamine type (Ru(RPy)/sub 2/Cl/sub 4/).

Energy Technology Data Exchange (ETDEWEB)

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it ...

Energy Technology Data Exchange (ETDEWEB)

Hydrogenation of carbon monoxide at 101.3 kPa has been studied over a series of ion-exchanged Ru catalysts supported on NaX, NaY, KL, Na mordenite, and HY zeolites. The type of zeolite had pronounced effects on the activity and selectivity of the Ru. The specific activity would appear to be related to the dispersion of reduced ruthenium in the zeolite. Methane selectivity, however, seems to be strongly influenced by the type and concentration of alkali cations remaining in the ion-exchanged zeolite. These cations appear to promote chain growth much as traditional alkali promoters would, though perhaps more indirectly. Due to bifunctional properties of the zeolite-supported catalysts, a significant fraction of C/sub 4/ was in the form of isobutane. Formation of isobutane seems to be related to either the Si/Al ratio in the zeolites or the concentration of the remaining alkali cations, but not to the OH concentration. In addition, H/sub 2/ ...

International Nuclear Information System (INIS)

The performance of larger than bench scale ion exchange systems is evaluated by using solutions containing trace amounts of "1"3"7Cs, "8"5Kr, and "1"3"1I, and large amounts of either NaCl or Na_2HPO_4, H_3BO_3, and LiOH. The significant finding in this study is that the empirical rules of ionic selectivity of strong acid cation and strong base anion resins were followed by all ionic species, even though concentrations of some macrocomponents were nearly 10"6 times those of trace components. Other results of possible importance are the correlation between the instantaneous decontamination factor (DF) and the efficiency of column exchange capacity utilization, and the concept of time average decontamination factor (anti DF). The plot of anti DF vs. feed throughput will serve as a guide in determining when the feed should be discontinued in order to achieve a desired anti DF. Both of these correlations are derived from the breakthrough curves.

International Nuclear Information System (INIS)

Decomposition of organic compounds contained in the spent ion exchange resins is considered effective in reducing the waste volume. A system using the wet-oxidation process has been studied for the treatment of the spent resins stored at Trino Nuclear Power Plant owned by SOGIN. Compared with various processes for treating sludge and resin, the wet-oxidation system is rather simple and the process conditions are mild. Not contaminated ion exchange resin samples similar to those ones used in Trino NPP were processed by wet-oxidation and appropriate decomposition of the organic compounds was verified. After decomposition the residue can be solidified with cement for final disposal. When compared with direct solidification without decomposition, the number of waste packages can be significantly reduced. Additional measures for conditioning secondary waste products have also been studied, and their ...

Energy Technology Data Exchange (ETDEWEB)

Reduction of occupational radiation exposure dose in a BWR plant is achieved by an elimination of crud in a BWR primary loop condensate stream by condensate demineralizer. Crud removal by condensate polisher improves year by year, a phenomenon called the Aging Effect of Ion Exchange Resins. The cause of this phenomenon is assumed to be mainly due to changes in the cation resin property becoming more crud adsorptive, where a typical change in physical property of aged cation resin is an increase in water retention capacity. Assuming that the crud removal efficiency was influenced by a crosslinkage of cation resin, an attempt was made to enhance this removal efficiency by decreasing the crosslinkage and satisfactory results were obtained. As a result, new gel type cation resins were developed with lower crosslinkage and larger surface areas, as compared with conventional gel type resins. The crosslinkage degree of these new cation resins are ...

Energy Technology Data Exchange (ETDEWEB)

This patent describes a process for preparing of an ion exchanger, comprising: treating an ionically inert activated charcoal porous support with an aqueous solution of metal oxychloride selected from the group consisting of zirconium and titanium oxychlorides so as to impregnate the pores of the support with the solution; separating the treated support from excess metal oxychloride solution; converting the metal oxychloride to a hydrous metal oxide precipitate in the pores of the support at a pH above 8 and above the pH whereat the hydrous metal oxide and activated charcoal support have opposite zeta potentials and sufficient to hydrolyze the metal oxychloride. It also describes a process for preparing an ion exchanger comprising: treating granulated activated charcoal with a concentrated solution of a metal oxychloride from the group consisting of zirconium and titanium oxychlorides, degassing the ...

Energy Technology Data Exchange (ETDEWEB)

Conventional methods for removing metals from aqueous solutions include chemical precipitation, chemical oxidation or reduction, ion exchange, reverse osmosis, electrochemical treatment and evaporation. The removal of radionuclides from aqueous waste streams has largely relied on ion exchange methods which can be prohibitively costly given increasingly stringent regulatory effluent limits. The use of microbial cells as biosorbants for heavy metals offers a potential alternative to existing methods for decontamination or recovery of heavy metals from a variety of industrial waste streams and contaminated ground waters. The toxicity and the extreme and variable conditions present in many radionuclide containing waste streams may preclude the use of living microorganisms and favor the use of non-living biomass for the removal of actinides from these waste streams. In the work presented here, we have ...

International Nuclear Information System (INIS)

A suspension-firing type radioactive waste incineration system is developed and cold demonstration testing of ceramic filters for the system are carried out. The incineration system, which is useful for a wide variety of waste materials, can serve to simplify the facilities and to reduce the costs for waste disposal. The incineration system can be used for drying-processing of concentrated waste liquids and disposal of flame resistant materials including ion exchange resins and rubber, as well as for ordinary combustible solid materials. An on-line backwash system is adopted to allow the ceramic filters to operate stably for a long period of time. For one-step filtering using the ceramic filter, the decontamination factor is greater than 10"5 for the processing of various wastes. In a practical situation, there exist vapor produced by the spray drier and the cladding in used ion exchange resin, which ...

Energy Technology Data Exchange (ETDEWEB)

Bench-scale batch equilibration tests have been conducted with supernatants from two underground tanks at the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to determine the effectiveness of selected ion exchangers in removing cesium, strontium, and technetium. Seven sorbents were evaluated for cesium removal, nine for strontium removal, and four for technetium removal. The results indicate that granular potassium cobalt hexacyanoferrate was the most effective of the exchangers evaluated for removing cesium from the supernatants. The powdered forms of sodium titanate (NaTiO) and cystalline silicotitanate (CST) were superior in removing the strontium; however, for the sorbents of suitable particle size for column use, titanium monohydrogen phosphate (TiHP {phi}), sodium titanate/polyacrylonitrile (NaTiO-PAN), and titanium monohydrogen phosphate/polyacrylonitrile (TiP-PAN) gave the best results and were about ...

International Nuclear Information System (INIS)

Zirconium phosphate was one of the earliest inorganic ion-exchange suggested for removing strontium and cesium from aqueous nuclear waste. This paper studied ionic exchange to remove Cs-137 and Sr-90 by using different cationic of zirconium phosphate. In this case the parameters studied were the effect of temperature and ion concentration to percent up take and distribution coefficients. It is also conducted the study on column experiments to determine the breakthrough curves for Cs-137 and Sr-90. The result showed the potential of use of zirconium phosphate in radioactive waste treatment. (author)

Energy Technology Data Exchange (ETDEWEB)

A simple and rapid procedure was developed for the purification of cyclotron-produced {sup 203}Pb via the {sup 203}Tl(d,2n) {sup 203}Pb reaction. A Pb(II) selective ion-exchange resin, with commercial name Pb Resin from Eichrom Technologies, Inc., was used to purify {sup 203}Pb from the cyclotron-irradiated Tl target with excellent recovery of the enriched Tl target material. The purified {sup 203}Pb was used to radiolabel the monoclonal antibody Herceptin. The in vitro and in vivo properties of the {sup 203}Pb radioimmunoconjugate were evaluated.

British Library Electronic Table of Contents (United Kingdom)

The increasing environmental concern and promotion of ''green processes'' are forcing the substitution of traditional acid and base homogeneous catalysts by solid ones. Among these heterogeneous catalysts, zeolites and zeotypes can be considered as real ''green'' catalysts, due to their benign nature from an environmental point of view. The importance of these inorganic molecular sieves within the field of heterogeneous catalysis relies not only on their microporous structure and the related shape selectivity, but also on the flexibility of their chemical composition. Modification of the zeolite framework composition results in materials with acidic, basic or redox properties, whereas multifunctional catalysts can be obtained by introducing metals by ion exchange or impregnation procedures...

Energy Technology Data Exchange (ETDEWEB)

The effects of temperature and the use of macroreticular resins were studied in lithium isotope separation by an ion-exchange method. The isotope separation factors obtained decreased by increasing the temperature, and the factors for macroreticular resins were identical with those for the usual gel-type resins. However, the performance of isotope separation per unit band length in displacement chromatography was found to be improved by increasing the temperature and using macroreticular resins, because accelerating the interphase mass transfer caused the reduction of HETP (Height Equivalent to a Theoretical Plate).

International Nuclear Information System (INIS)

The bituminzation of decontamination and ion exchange resin stripping wastes with four grades of asphalt was investigated to determine the effects of asphalt type on the properties of the final products. All waste forms deformed readily under light loads indicating they would flow if not restrained. It was observed in all cases that product leaching rates increased as the hardness of the asphalt used to treat the waste increased. If bituminization is adopted for any Ontario Hydro aqueous radioactive wastes they should be treated with soft asphalt to obtain optimum leaching resistance and mechanical stability during interim storage should be provided by a corrosion resistant container.

Energy Technology Data Exchange (ETDEWEB)

CoTreat, a new inorganic ion exchange media, has been studied in the laboratory to support its application as a pre- coat to existing Funda filters in THORP feed pond plant (Sellafield, UK). This is a novel way of application of CoTreat, which is usually utilized in fixed-bed ion exchange columns in a granular form. The results present the effect of operating conditions (CoTreat dose, pond water chemistry) on CoTreat performance for the removal of Co-57 tracer from simulated pond water. Major findings include the strong dependence of Co-57 decontamination factor (DF) on feed activity. At the 200 Bq/L feed level, the observed DF was 10-20 but rose to 1000 and above when the feed level was increased to 20000 Bq/L. Calcium present in the feed was found to decrease the DF at concentrations higher than 1 ppm. The laboratory studies showed significantly higher DF's than what has been observed in ...

Energy Technology Data Exchange (ETDEWEB)

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). ...

International Nuclear Information System (INIS)

A series of separation experiment was performed in order to study a multi-functional spent fuel reprocessing process based on ion-exchange technique. The tertiary pyridine-type anion-exchange resin was used in this experiment and the mixed oxide fuel highly irradiated in the experimental fast reactor ''JOYO'' was used as a reference spent fuel. As the result, "1"0"6Ru + "1"2"5Sb, "1"3"7Cs + "1"5"5Eu + "1"4"4Ce, plutonium, americium and curium could be separated from the irradiated fuel by only three steps of ion-exchange. The decontamination factor of "1"3"7Cs and trivalent lanthanides ("1"5"5Eu, "1"4"4Ce) in the final americium product exceeded 3.9 x 10"4 and 1.0 x 10"5, respectively. The decontamination factor for the mutual separation of "2"4"3Cm and "2"4"1Am was larger than 2.2 x 10"3 for the americium product and, moreover, the content of "1"3"7Cs, trivalent lanthanides and "2"4"3Cm included in "2"4"1Am product did not exceed 2 ppm. These ...

Energy Technology Data Exchange (ETDEWEB)

Components of various forest and agricultural residue biomass-including the polyphenolic compounds-were converted into aqueous solution and/or suspension by extraction and digestion. Some biomass components reacted vigorously under alkaline catalysis with formaldehyde and initially showed a high degree of exothermic reaction; however, other components did not react as vigorously under these conditions, indicating that different biomass materials require different methods to obtain optimum reactivity for the copolymerization with phenol. Our primary goal is to develop adhesives capable of producing acceptable bond quality, as determined by the wood products industries` standards, under a reasonable range of gluing conditions. Copolymer resins of phenol, formaldehyde, and biomass components were synthesized and evaluated for gluability of bonding exterior grade structural replaced with chemicals derived from peanut hulls, pecan shell flour, pecan pith, southern pine ...

International Nuclear Information System (INIS)

Here we reported a two-step procedure for preparing a novel polymeric based solid-solid phase change heat storage material. Firstly, a copolymer monomer containing a polyethylene glycol monomethyl ether (MPEG) phase change unit and a vinyl unit was synthesized via the modification of hydrogen group of MPEG. Secondly, by copolymerization of the copolymer monomer and phenyl ethylene, a novel polymeric based solid-solid phase change heat storage material was prepared. The composition, structure and properties of the novel polymeric based solid-solid phase change material were characterized by IR, "1H NMR, DSC, WAXD, and POM, respectively. The results show that the novel polymeric based solid-solid phase change material possesses of excellent crystal properties and high phase change enthalpy.

Energy Technology Data Exchange (ETDEWEB)

The near normal incidence reflectivity of the ferromagnets U/sub 3/P/sub 4/ and U/sub 3/As/sub 4/ and the isostructural but diamagnetic compounds Th/sub 3/P/sub 4/ and Th/sub 3/As/sub 4/ has been measured from 0.03 to 12 eV. Trithorium tetraphosphide and tetraarsenide are shown to be indirect gap semiconductors with gap energies of 0.43 and 0.39 eV, respectively. U/sub 3/P/sub 4/ and U/sub 3/As/sub 4/ display similar sets of p..-->..d transitions than the corresponding thorium compounds, however, they are shifted by 0.85 eV to lower photon energies. It is concluded that the uranium compounds are metals due to a merging of the valence p band into the 6d conduction band giving direct experimental evidence for a p-f mixing effect of the same size. Energy level schemes are derived.

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Based on the single-particle levels given by Nilsson, the intrinsic and effective (with collective effects) level density parameters as a function of the excitation energy for the "1"8"6Os, "1'8"7Ir, "1"8"9Os and "1"9"3Au deformation nuclei have been calculated in the range of the excitation energy up to 150 MeV. The calculated fission probabilities P_f (U) are consistent satisfactorily with the experimental data when a nonadiabatic estimation of the collective effects was used to calculated the nuclear level density parameters.

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It is an object of the claimed invention to combine chemical treatment with microfiltration process to treat groundwater, leachate from contaminated soil washing, surface and run-off waters contaminated with toxic metals, radionuclides and trace amounts of organics from variety of sources. The process can also be used to treat effluents from industrial processes such as discharges associated with smelting, mining and refining operations. Influent contaminants amenable to treatment are from a few mg/L to hundreds of mg/L. By selecting appropriate precipitation, ion exchange and adsorption agents and conditions, efficiencies greater than 99.9 percent can be achieved for removal of contaminants. The filtered water for discharge can be targeted with either an order of magnitude greater or lower than contaminant levels for drinking water.

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The use of high-performance ion exchangers allows a trace-matrix-separation (SMT) directly followed by an ion chromatographic (IC) separation of the analytes. Based on the principles described in Part 1, a combined procedure IC-SMT-IC for metallic impurities in Mo and W is presented. Up to 12 metal traces (Fe, Cu, Pb, Zn, Ni, Co, Cd, Ca, Mn, Sr, Mg and Ba) can be determined in one run with 35 min. A special method for traces of U and Th is also given. Detection limits are typically 10-100 ng g{sup -1} in the metal sample. (author). 14 refs.; 10 figs.; 6 tabs.

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The extraction of rare earth elements, yttrium and aluminium from red mud resulting from alumina production with the ion-exchange resin KU-2-8n was studied. Experimental results are presented. The technology of hydrometallurgical processing of pulps obtained by sorption extraction of scandium from red mud is developed. It is shown that in the process of precipitation from sulfate sulfuric acid desorbate it became possible to obtain a high degree of rare earths deposition. The use of sodium hydroxide makes it possible to obtain a maximum deposition of rare earths and aluminium - 99.9 %. Aluminium leaching from crude composite concentrate gives a possibility to get concentrates which 15 - 20 times richer in yttrium and rare earths

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A simple method is presented for the separation of lead-203 from copper-backed thallium cyclotron targets. The procedure involves cation-exchange chromatography in hydrochloric acid and hydrochloric acid-acetone mixtures. Further purification involves anion-exchange chromatography in nitric acid-hydrobromic acid mixtures. A cation-exchange column containing 3.0 g of resin can handle as much as 15 g of thallium and 160 mg of copper. An anion-exchange column containing 3.0 g of resin can separate lead from up to 200 mg of thallium and 10 mg of copper. Separations are extremely sharp and less than 0.1 ..mu..g of thallium and less than 0.1 ..mu..g of copper remain in the lead-203 fraction.

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Feasibility of using fixed bed column of conventional ion exchangers/sorbent and chemical precipitation based processes have been examined for the effective removal of the very low levels of 106Ru activity from NH4NO3 effluent generated during wet processing of rejected sintered depleted uranium fuel pellets. Based on the results, a simple process involving precipitation of cobalt sulphide along with ferric hydroxide was selected and further optimization of process variables was carried out. The optimized process has been found to be highly efficient in reducing 106Ru activity down to extremely low levels.

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A significant number of biosorption studies on the removal of heavy metal from aqueous solutions have been conducted worldwide. Nearly all of them have been directed towards optimizing biosorption parameters to obtain the highest removal efficiency while the rest of them are concerned with the biosorption mechanism. Combinations of FTIR, SEM-EDX, TEM as well as classical methods such as titrations are extremely useful in determining the main processes on the surfaces of biosorbents. Diverse functional groups represented by carboxyl, hydroxyl, sulfate and amino groups play significant roles in the biosorption process. Solution pH normally has a large impact on biosorption performance. In brief, ion exchange and complexation can be pointed out as the most prevalent mechanisms for the biosorption of most heavy metals. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

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A simple and rapid procedure was developed for the purification of cyclotron-produced "2"0"3Pb via the "2"0"3Tl(d,2n) "2"0"3Pb reaction. A Pb(II) selective ion-exchange resin, with commercial name Pb Resin from Eichrom Technologies, Inc., was used to purify "2"0"3Pb from the cyclotron-irradiated Tl target with excellent recovery of the enriched Tl target material. The purified "2"0"3Pb was used to radiolabel the monoclonal antibody Herceptin. The in vitro and in vivo properties of the "2"0"3Pb radioimmunoconjugate were evaluated.

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Single stage separation factors ..cap alpha.. have been determined for /sup 6/Li and /sup 7/Li between lithium ions in methanol and complexed ions with a cryptand (2 sub(B), 2, 1) polymer. The /sup 6/Li was concentrated in the cryptand. The separation factors were compared with the values of other chemical exchange systems. The maximum enrichment factor obtained was epsilon = 0.047 +- 0.002. The figure is one of the greatest in the chemical exchange reactions without valence change and almost 10 times larger than the values of ion exchangers. The variation in ..cap alpha.. depending on the chemical species was small in the non-aqueous system. High enrichment of lithium isotopes was expected to be achievable by means of the chromatographic application of the cryptand (2 sub(B), 2, 1).

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When clinoptilolite is immobilized in cement-based composites, a series of reactions occur, leading to release of Cs. These reactions occur in three overlapping stages: a rapid ion exchange, followed by a somewhat slower reaction between clinoptilolite and principally the Ca(OH)_2 component of cement, and, in the longer term, slower reactions with C-S-H leading either to formation of low-lime C-S-H at temperatures below 100"0C or 11 A (1.1 nm) tobermorite at higher temperatures. Kinetic data are presented to evaluate the rate of physical consumption of the zeolites at 70 and 150"0C. Reactions occurring above 100"0C appear to result in the development of extensive microcracking of cement-zeolite composites containing 50% zeolite.

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The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a water retention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form, and the Dowex 50W resins have characteristic water retention capacities. These tests conclude that the ion exchange resins in use in FB-Line meet the approved safety document criteria for cross-linking, ionic form, and resin type.

International Nuclear Information System (INIS)

A method is described for determination of aluminium, cadmium, cobalt, chromium, copper, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, zinc, titanium and vanadium in iron ore. After dissolution, a 1 gram sample of iron ore is applied to a column of AGI-X8 anion exchange resin (chloride form), in 100 ml of 7M HCl. Aluminium, chromium, calcium, magnesium, sodium, potassium, manganese, nickel, lead, strontium, titanium and vanadium are eluted with 7M HCl; iron, copper and cobalt are eluted with 0.5M HCl; cadmium and zinc are eluted with 2M HNO_3. Iron is subsequently removed from copper and cobalt by a solvent extraction with methyl isobutyl ketone. The elements are determined in the eluates by atomic absorption spectrometry, except for titanium and vanadium, which are determined spectrophotometrically.

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This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows time-advantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore? and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most ef...

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The competitive adsorption of nitrate, chloride and carbonate in layered double hydroxides (LHD) with the general formula Formula Not Shown was investigated. Both normal ion exchange by exposure to a solution containing different anions, as well as addition of calcined material to solution thereby exploiting the memory effect of LDHs was studied. Changes in the interlayer anion changed the interlayer spacing of the LDH. The order of preference of intercalation was Formula Not Shown . When multiple anions were present in the exchange solution, LDHs with several distinct interlayer spacing were produced indicating that LDHs with different anions in the interlayer existed at the same time. However for extended exchange times (14days) where high concentrations of carbonate anion were present, ...

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A new procedure for preparing an 211At-labeled radiopharmaceutical is suggested. The 211At? anion forms a strong bond with the Rh3+ cation incorporated in the complex with a thiother ligand, 1,5,9,13-tetrathiacyclohexadecane-3,11-diol (16-S4-diol). The reaction conditions are optimized with 131I as astatine analog. The complexes are studied by paper electrophoresis, ion exchange, and thin-layer chromatography. The kinetics of the addition of the 131I? anion to Rh(16-S4-diol) and the dependence of the yield of the forming complex 131I-Rh(16-S4-diol) on the temperature, solution acidity, and reactant concentrations are examined. Taking into account the results obtained, the complex 211At-Rh(16-S4-diol) is prepared by adding astatide (211 At?) to equivalent amounts of RhCl3 and the tetrathioe...

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Lead 203 has been used as a tracer for lead in the field of nuclear medicine for several years. It is produced in a cyclotron usually by proton or deuteron bombardment of a thallium target principally by the p,n or d,2n reaction on "2"0"3Tl or the p,3n or d,4n reaction on "2"0"5Tl. Several different methods have been reported for the separation of "2"0"3Pb from the thallium target. These generally involve a combination of precipitation and solvent extraction techniques. A new method has been developed for the separation of Pb from Tl using ion exchange chromatography over hydrous zirconium oxide (HZO). Lead is taken up by this inorganic ion exchanger at pH > 3 whereas Tl(I) is not. Lead can subsequently be eluted with acid of pH 1-1.5. The recovery of "2"0"3Pb has been approximately 75% and the Tl impurity level has not been in excess of 10 ppm. Reference is made to the application of this separation ...

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Most of the low-level liquid radioactive wastes generated from PWR plants are classified into high or low total suspended solid(HTDS or LTDS), radio-chemical waste and radioactive laundry waste. Although the evaporation process has a high decontamination ability, it has several problems such as corrosion, foaming, and congestion. A new liquid waste disposal process using the ion-exchange demineralizer(IED) has been introduced into the Yonggwang NPP 5 and 6 to complement the current evaporation process. To determine the differences, these two methods have been compared in this study. Those aspects compared here were the released radioactivity volume of the liquid radioactive wastes, The dose of off-site residents, the decontamination factor, and the amount of the solid radioactive wastes. While it was expected that the liquid radioactive waste volume in the evaporating system would be 20 percent higher than in the IED, the actual volume of the liquid radioactive ...

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A comparative study on the interaction of different PEG-containing diblock copolymers including SA400, SA600, SA1500 and OA1500 (stearyl and oleyl esters of polyethylene glycol with 400, 600 and 1500 molecular weights, respectively) with bovine serum albumin (BSA) was carried out using isothermal titration calorimetry (ITC), attenuated total reflectance Fourier transform infrared (ATR-FTIR), circular dichroism (CD), and fluorescence spectroscopies. ITC data show that SA400, SA600, SA1500 and OA1500 bind to BSA, with association constants of (14.5, 3.16, 50.7 and 17.6)x103M-1, respectively. Results also show that the binding is enthalpically driven, disfavored by conformational entropy. Quantitative analysis of the FTIR absorbance spectra at amide Iprime (1600-1700cm-1) as well as far UV ci...

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The phase transition behaviour of polyethylene-b-poly(ethylene oxide) (PE-b-PEO) diblock copolymer with relatively short chain lengths has been studied on the basis of temperature dependent infrared and Raman spectral measurements and synchrotron WAXD/SAXS simultaneous measurements, from which the concrete structural changes were deduced successfully from the various levels of molecular chain conformation, chain packing mode and higher-order structure. The higher-order structure has been found to transform between lamella, perforated lamella, gyroid, cylinder and sphere structures. The inner structural changes occurring in the polyethylene and poly(ethylene oxide) parts have been related with these morphological changes. The morphological transition from lamella to gyroid occurs with keeping the crystalline state of polyethylene parts. This apparently curious transition can be interpreted reasonably by assuming the thermally-activated chain motion in the crystal ...

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Natural, formaldehyde-treated and copolymer-grafted orange peels were evaluated as adsorbents to remove lead ions from aqueous solutions. The optimum pH for lead adsorption was found to be pH 5. The adsorption process was fast, reaching 99% of sorbent capacity in 10 min for the natural and treated biomasses and 20 min for the grafted material. The treated biomass showed the highest sorption rate and capacity in the batch experiments, with the results fitting well to a pseudo-first order rate equation. In the continuous test with the treated biomass, the capacity at complete exhaustion was 46.61 mg g{sup -1} for an initial concentration of 150 mg L{sup -1}. Scanning electronic microscopy and energy dispersive X-ray spectroscopy indicated that the materials had a rough surface, and that the adsorption of the metal took place on the surface. Fourier transform infrared spectroscopy revealed that the functional groups responsible for metallic biosorption were the -OH, ...

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The effect of the degree of degradation of the components of a model municipal plastic waste (a mixture of low-density polyethylene, high-density polyethylene, polypropylene and high-impact polystyrene) on the toughness and stability of recyclates compatibilised with a cooperative compatibilisation system (a mixture of ethylene-propylene statistical and styrene-butadiene block copolymers with a secondary amine-based stabiliser) was studied. It was shown that good impact strength was achieved for recyclates having components with a low or medium degree of degradation. Mechanical properties of recyclates having the components with a high degree of degradation are deteriorated. The addition of the cooperative compatibilisation system leads to a higher thermo-oxidative stability of recyclates ...

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Three simulated low-level reactor wastes were dried using a spray dryer-baghouse system. The three aqueous feedstocks were sodium sulfate waste characteristic of a BWR, boric acid waste characteristic of a PWR, and a waste mixture of ion exchange resins and filter aid. These slurries were spiked with nonradioactive iron, cobalt, and manganese (representing corrosion products) and nonradioactive cesium and iodine (representing fission products). The throughput for the 2.1-m-diameter spray dryer and baghouse system was 160-180 kg/h, which is comparable to the requirements for a full-scale commercial installation. A free-flowing, dry product was produced in all of the tests. The volume reduction factor ranged from 2.5 to 5.8; the baghouse decontamination factor was typically in the range of 10"3 to 10"4. Using an overall system decontamination factor of 10"6, the activity of the off-gas was calculated to be one to two orders of magnitude less than ...

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By means of neutron activation analysis, injured and adjacent uninjured human heart tissue from 12 autopsy cases with myocardial infarction are investigated with respect to the concentration of 23 trace elements. The bulk elements K, Na and P are also determined. A recently developed ion-exchange technique, combined with subsequent y-spectrometry, is used. The following trace elements are determined: Ag, As, Au, Ba, Br, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mo, Rb, Sb, Sc, Se, Sm, Zn and W. In the injured tissue compared to the uninjured, calculation on a wet weight basis showed a decrease in Co, Cs, K, Mo, P, Rb and Zn, and an increase in Br, Ca, Ce, La, Na, Sb and Sm. The differences in Ca, La, Mo, P and Zn are dependent on the age of the myocardial infarction, and the regression lines for these elements are given. The concentration of the trace elements in uninjured tissue from infarcted hearts is compared to the concentration of these elements in normal heart ...

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The effect of neutralizing cations on the secondary reactions of the primary products from CO hydrogenation over ion-exchanged zeolite-supported Ru catalysts was investigated using zeolites with different alkali cations (Li/sup +/, Na/sup +/, K/sup +/, Rb/sup +/, Cs/sup +/). The transformation of olefins (propylene and butene) on the zeolites without the metal, under conditions similar to those used for CO hydrogenation, was also studied in order to understand the effect of the various constituents of the support, i.e., the Broensted acid sites generated during catalyst preparation and the alkali cations, on possible secondary reactions of the primary olefinic products. It was established that secondary acid-catalyzed reactions of these primary products can play a major role in shaping product selectivity during CO hydrogenation over zeolite-supported catalysts. Depending on the concentration and the strength of the acid sites, various competitive reaction paths ...

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A type of mesoporous ZrO{sub 2} was synthesized and its phosphate removal potential was investigated in this study. The adsorption isotherm, pH effect, ionic strength effect and desorption were examined in batch experiments. The adsorption data fitted well to the Langmuir model with which the maximum P adsorption capacity was estimated to be 29.71 mg P/g. The amount of phosphate adsorbed increased rapidly in the first 5 h and slowly towards the end of the run, suggesting the possible monolayer coverage of phosphate ions on the surface of the adsorbent. The phosphate adsorption tended to increase with a decrease of pH and an increase of ionic strength. A phosphate desorbability of approximately 60% was observed with 0.5 M NaOH, which indicated a relatively strong bonding between the adsorbed PO{sub 4}{sup 3-} and the sorptive sites on the surface of the adsorbent. The immobilization of phosphate probably occurs by the mechanisms of ion exchange ...

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Aminocyclopropane 1-carboxylic acid (ACC) synthase, a pyridoxal phosphate utilizing enzyme, catalyzes the conversion of S-adenosylmethionine to ACC, the rate limiting step in the biosynthesis of the plant hormone, ethylene. Ethylene, besides being involved in normal plant growth processes, is also produced in response to stress, e.g. wounding, pathogen infection, etc. The authors report the partial purification (400 fold) of ACC synthase from wounded pink tomato pericarp by classical techniques including ammonium sulfate precipitation, ion exchange and phenyl sepharose chromatography. Further purification results in a decrease in specific activity apparently due to the instability of the enzyme and the low levels present in plant tissue. Radiolabeling of a pyridoxal phosphate-utilizing protein in the ACC synthase enriched fraction was achieved. Evidence that this radiolabeled protein is ACC synthase will be presented. Amino acid sequence ...

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Sulfonated poly(ether ether ketone) (SPEEK) membranes with various degrees of sulfonation (DS) have been prepared as a potential membrane material for proton exchange membrane by sulfonation process using mixtures of (15-30% concentration) fuming sulfuric acid and (95-98%) concentrated sulfuric acid as the sulfonating agent. The sulfonation process was conducted at room temperature by varying the acid ratio and reaction time. The produced membranes were then characterized by evaluating the ion exchange capacity (IEC), water uptake, thermal stability, proton conductivity and methanol permeability as a function of degree of sulfonation. The proton conductivity of the sulfonated PEEK membranes with various DS was within the magnitude of 10"-"3 and 10"-"2 S cm"-"1 at room temperature and the methanol permeability was in the range of 3.45 x 10"-"7 to 2.73 x 10"-"6 cm"2 s"-"1. The overall membrane performance of the SPEEK membrane with 80% DS was six ...

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In the nuclear power stations of GDR the rough radioactive waste includes borat-containing evaporator bottoms and spent ion exchanger resins. For its final disposal in deep geological formations (rock salt mines) this waste has to be solidified. The experience of one year lasting operation of a steam heated thin-film evaporator (heating surface 2 m{sup 3}) for evaporator bottoms to be solidified with a solid content of 200-250 g/l are reported on. In short time such amount of water is abstracted from the rough waste that due to the borate content a hot high-viscous product passes from evaporator to waste drum and there solidifies like glass to monolith. The product quality depends on the adjustment of the flow-equilibrium in the evaporator. Boric acid is used as matrix for the radioactive residues. The residual water content of the solidified waste product was about 15-20%, the volume reduction was V{sub f}=5...6. In order to be sure to get a ...

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The deposition of platinum on various carbon blacks was carried out by forming active functional groups on the surface of the carbon support, and exchanging these active groups with different platinum complexes. Using H{sub 2}PtCl{sub 6} solution, an impregnation rather than an exchange takes place. However, using divalent platinum complexes [Pt(NH{sub 3}){sub 4}]{sup 2+}, a fast exchange takes place which leads to extremely small platinum particles highly dispersed on the surface of carbon black. A comparison of the catalytic activities of platinum supported on various carbon blacks was also carried out. The performances of PEFC (Polymer Electrolyte Fuel Cell) based on the process of the ion exchange are reported. (authors) 3 refs.

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The concept of nanocrystal conversion chemistry, which involves the use of pre-formed nanoparticles as templates for chemical transformation into derivative solids, has emerged as a powerful approach for designing the synthesis of complex nanocrystalline solids. The general strategy exploits established synthetic capabilities in simple nanocrystal systems and uses these nanocrystals as templates that help to define the composition, crystal structure, and morphology of product nanocrystals. This article highlights key examples of 'conversion chemistry' approaches to the synthesis of nanocrystalline solids using a variety of techniques, including galvanic replacement, diffusion, oxidation, and ion exchange. The discussion is organized according to classes of solids, highlighting the diverse target systems that are accessible using similar chemical concepts: metals, oxides, chalcogenides, phosphides, alloys, intermetallic compounds, sulfides, and ...

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The aim of this article was to investigate the interactions of metal cations in aqueous solutions with the biomass of the freshwater macroalga Vaucheria sp. This problem is important when elaborating new applications of biosorption, e.g. the production of mineral feed additives for livestock from the biomass of algae enriched with microelement ions. Potentiometric titration was applied as a quick and cheap screening test to search for new efficient biosorbents. It revealed a variety of functional groups capable of cation exchange on the macroalgal surface, including carboxyl, phosphate, hydroxyl or amino groups. Fourier transform infrared spectroscopy on natural and chromium-loaded Vaucheria sp. confirmed that carboxyl groups played a dominant role in the biosorption. The study also showed that Ca(II), Na(I), K(I), and Mg(II) ions were released from the biomass after biosorption of Cu(II), Mn(II), Zn(II), and Co(II) ions, indicating that ion ...

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In order to establish coal NOx preventive measures, discussions were given on formation of N2 in the fixed-bed pyrolysis of low rank coals and the mechanisms thereof. Chinese ZN coal and German RB coal were used for the discussions. Both coals do not produce N2 at 600{degree}C, and the main product is volatile nitrogen. Conversion into N2 does not depend on heating rates, but increases linearly with increasing temperature, and reaches 65% to 70% at 1200{degree}C. In contrast, char nitrogen decreases linearly with the temperature. More specifically, these phenomena suggest that the char nitrogen or its precursor is the major supply source of N2. When mineral substances are removed by using hydrochloric acid, their catalytic action is lost, and conversion into N2 decreases remarkably. Iron existing in ion-exchanged condition in low-rank coal is reduced and finely diffused into metallic iron particles. The particles react with heterocyclic nitrogen compounds and turn ...

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A novel method for the determination of metoclopramide (MCP) using electrogenerated chemiluminescence (ECL) is presented. A tris(2,2prime-bipyridyl)dichlororuthenium(II) (Ru(bpy)32+)-doped silica (RuDS) nanoparticle/perfluoinated ion-exchange resin (Nafion) with nanocomposite membrane modified glassy carbon electrode (GCE) is used. The Ru(bpy)32+ encapsulation interior of the silica nanoparticle maintains its electrochemical activities and also reduces Ru(bpy)32+ leaching from the silica matrix when immersed in water due to the electrostatic interaction. The analytical performance of this ECL sensor for MCP is shown in detail. Under optimal experimental conditions, it has good linearity in the concentration range from 2x10-8mol/L to 1x10-5mol/L (R=0.9989) with a detection limit of 7x10-9mo...

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The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich-Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini-Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the rate of adsorption followed the pseudo second-order kinetics well. The thermodynamics constants {delta}G{sup o}, {delta}H{sup o} and {delta}S{sup o} of the adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum were endothermic and spontaneous.

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Wastewater from a food-manufacturing plant with a low concentration of organic matter was treated at 37 centigrade in an anaerobic fluidized-bed reactor or in an upflow anaerobic sludge blanket. As the influent TOC (total organic carbon) concentration decreased, the TOC removal efficiency in these reactors decreased from 85% to 65%. The concentration of suspended solids in the effluent could be reduced to 20 mg/l, which corresponded to 7% of that in the influent. The effluent from both reactors was treated aerobically in a fixed-bed reactor. The TOC concentration and optical density of effluent from the aerobic treatment were reduced to 5 mg/l and 0.005, respectively. When the effluent treated anaerobically or aerobically was passed over an activated carbon column, the effluent TOC concentration was reduced to 2 to 3 mg/l. The conductivity in raw wastewater was remarkably reduced on an ion-exchange resin column. Ultra-pure water for industrial use was obtained by ...

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A pretreatment flowsheet was tested for separating key radionuclide components from the sludge stored in one of the high level waste tanks (B-110) at the Hanford Site; this sludge resulted primarily from the bismuth phosphate process, which was one of the three major plutonium separation processes used at Handford. This test involved (1) washing with water, (2) caustic leaching, (3) acid dissolution, (4) separation of transuranic elements (TRUs) by extraction with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), (5) separation of Sr by extraction with di-t-butylcyclohexano-18-crown-6, (6) separation of Cs from the acid-dissolved sludge solution by treatment with ammonium molybdophosphate (AMP), and (7) separation of Cs from the sludge wash and caustic leach solutions by ion exchange using a phenol-formaldehyde resin (CS-100). The results of the radionuclide separation steps indicated that the proposed flowsheet is a viable ...

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Paper describes a new procedure to synthesize a pharmaceutical containing "2"1"1At. "2"1"1At"- anion was found to bind strongly with Rh"3"+ cation complexing with a thio-ether ligand - 1,5,9,13-tetratiacyclohexadecane-3,11-diol (16-S4-diol). One made use of "1"3"1I isotope to seek for the optimal conditions of the reaction. The derived complexes were studied by means of the paper electrophoresis, the ion exchange, the surface chromatography. One studied the kinetics of "1"3"1I"- anion binding with Rh(16-S4-diol), the dependence of the yield of "1"3"1I-Rh(16-S4-diol) forming complex on the temperature. the acidity of the reaction mixture and the concentration of the reagents. On the basis of the determined conditions of the synthesis one prepared "2"1"1At-Rh(16-S4-diol) complex by more astatide ("2"1"1At"-) to the equivalent amounts of RhCl_3 and tetra-thio-ether (16-S4-diol). One studied its behaviour

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Polyurethane (PU) foam was combined with protein drug-loaded pH-sensitive alginate-bentonite hydrogel for wound dressings. Alginate is a linear copolymer composed of 1?4-linked ?-D-mannuronic acid (M) and its c-5-epimer ?-Lguluronic acid (G). The amount of (M) and (G) and their sequential distribution are varied depending on the alginate source. Soluble sodium alginate can become a hydrogel when cross-linked with divalent cations and has widespread applications in the food, drink, pharmaceutical and bioengineering industries. Recently, it has been also proposed as a biomaterial for drug delivery systems. Bentonites are the natural inorganic polymers consisting of a large proportion of expandable clay minerals with a three-layer structure such as montmorillonite, beidellite, nontronite, etc...

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Alzheimer's disease (AD) is a neurodegenerative disorder for which the research of new treatments is highly challenging. Since the fibrillogenesis of amyloid-b peptide 1-42 (Ab1-42) peptide is considered as a major cause of neuronal degeneration, specific interest has been focused on aromatic molecules for targeting this peptide. In this paper, the synthesis of selegiline-functionalized and fluorescent poly(alkyl cyanoacrylate) nanoparticles (NPs) and their evaluation for the targeting of the Ab1-42 peptide are reported. The synthetic strategy relied on the design of amphiphilic copolymers by tandem Knoevenagel-Michael addition of cyanoacetate derivatives, followed by their self-assembly in aqueous solutions to give the corresponding NPs. Different cyanoacetates were used: (i) hexadecyl cy...

British Library Electronic Table of Contents (United Kingdom)

Nanocapsules coated by medicinal plants have many applications in drug manufacturing. Medicinal plants can be loaded on nanocapsules with polyesteric triblock copolymer poly ethylene glycol-poly butylene adipate-poly ethylene glycol (PEG-PBA-PEG) as shell and olive oil can be introduced as a core of nanocapsules by a method known as polymer deposition solvent evaporation method. In this research, first, certain amount of polymer, Matricaria recutita extract and olive oil were mixed with acetone and then, water was added to the solution using magnetic stirrer. After which the acetone was removed by vacuuming and finally nanocapsules were found by freezing-drier. The study showed the size of nanocapsules depends on variety of factors such as the ratio of polymer to oil and concentration of p...

British Library Electronic Table of Contents (United Kingdom)

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up inc...

Energy Technology Data Exchange (ETDEWEB)

This report describes experimental results for the selective removal of strontium and cesium from simulated waste solutions using monosodium titanate (MST) and crystalline silicotitanate (CST)-laden filter cartridges. Four types of ion exchange cartridge media (CST and MST designed by both 3M and POROX{reg_sign}) were evaluated. In these proof-of-principle tests effective uptake of both Sr-85 and Cs-137 was observed. However, the experiments were not performed long enough to determine the saturation levels or breakthrough curve for each filter cartridge. POREX{reg_sign} MST cartridges, which by design were based on co-sintering of the active titanates with polyethylene particles, seem to perform as well as the 3M-designed MST cartridges (impregnated filter membrane design) in the uptake of strontium. At low salt simulant conditions (0.29 M Na{sup +}), the instantaneous decontamination factor (D{sub F}) for Sr-85 with the 3M-design MST cartridge ...

Energy Technology Data Exchange (ETDEWEB)

The presence of water in export coals increases transport and handling costs. Coarse (+0.5 mm) coal constitutes the majority of the product, and small changes in its final moisture content will have a significant effect on overall product moisture. An on-line moisture monitor was installed on a product belt immediately after a coarse coal centrifuge to continuously measure the moisture content of the coal from a single centrifuge. Basic studies were also conducted with a laboratory centrifuge specifically designed to characterize various coarse coal samples in terms of their water retention capacity. The moisture of the coarse coal (typically 6 to 9%) was found to vary by at least 1% at a particular plant, and by a number of percentage points between plants. An empirical model has been developed which can explain about 80% of the moisture variation from the 25 samples investigated. The rank of the coals ranged from 0.7 to 1.65% mean reflectance. The model identified four principle ...

International Nuclear Information System (INIS)

The authors present the results of an investigation of the effect of gamma radiation on the properties of low-molecular moulded polymethyl methacrylates (molecular weight distribution, physicomechanical properties, resistance to the effects of aqueous media and physiological solution) in the form of copolymers of methyl methacrylate with methyl (MA) or butyl acrylate (BA) with the brand names Dacryl-4B, Dacryl-2M and Dacryl-4M (4% BA; 2 and 4% MA respectively) having a molecular weight of around 10"5. For comparison, block polymethyl methacrylate with a molecular weight of 3 x 10"6 was used. The results of experiments on the ageing of unirradiated and irradiated specimens in a heated store-room (t = 10 - 20"0C) and at high temperatures (90"0C) are also given. It is shown that irradiation with doses of 2.5-20 Mrad leads to radiolysis of the above copolymers, accompanied by destructive processes. Evidence of this is an increase in the ...

Energy Technology Data Exchange (ETDEWEB)

From 1991 to 1996, key studies on the reutilization, treatment, and disposal technology of hazardous wastes have been incorporated into the national plan for environmental protection science and technology. At present, the research achievements have been accomplished, have passed national approval, and have been accepted. The author of this paper, as leader of the national group for this research work, expounds the newest achievements of the studies involving four parts: (1) the reutilization technology of electroplating sludge, including the ion-exchange process for recovering the sludge and waste liquor for producing chromium tanning agent and extracting chromium and colloidal protein from tanning waste residue; on the recovery of heavy metals from the electroplating waste liquor with microbic purification; on the demonstration project of producing modified plastics from the sludge and the waste plastics; and on the demonstration of the recovery of heavy metals ...

Energy Technology Data Exchange (ETDEWEB)

The transfer kinetics of the neutral glycosphingolipid gangliotetraosylceramide (asialo-GM1) were investigated by monitoring tritiated asialo-GM1 movement from donor to acceptor vesicles. Two different methods were employed to separate donor and acceptor vesicles at desired time intervals. In one method, a negative charge was imparted to dipalmitoylphosphatidylcholine donor vesicles by including 10 mol% dipalmitoylphosphatidic acid. Donors were separated from neutral dipalmitoylphosphatidylcholine acceptor vesicles by ion-exchange chromatography. In the other method, small, unilamellar donor vesicles and large, unilamellar acceptor vesicles were coincubated at 45 degrees C and then separated at desired time intervals by molecular sieve chromatography. The majority of asialo-GM1 transfer to acceptor vesicles occurred as a slow first-order process with a half-time of about 24 days assuming that the relative concentration of asialo-GM1 in the phospholipid matrix was ...

Energy Technology Data Exchange (ETDEWEB)

The Rb-Sr isotope systematics of bedrock, soil digests, and the cation exchange fraction of soils from a granitic glacial soil chronosequence in the Wind River Mountains, Wyoming, USA, were investigated. Six soil profiles ranging in age from 0.4 to {approximately}300 kyr were studied and revealed that the {sup 87}Sr/{sup 86}Sr ratio of exchangeable strontium in the B-horizons decreased from 0.7947 to 0.7114 with increasing soil age. Soil digests of the same samples showed much smaller variation in {sup 87}Sr/{sup 86}Sr from 0.7272 to 0.7103 and also generally decreased with increasing soil age. Elevation of the {sup 87}Sr/{sup 86}Sr ratios of Sr released by weathering over the soil digest and bedrock values results from the rapid weathering of biotite to form hydrobiotite and vermiculite in the younger soils. Biotite is estimated to weather at approximately eight times the rate of plagioclase (per gram of mineral) in the youngest soil profile and decreases to a rate of only ...

International Nuclear Information System (INIS)

Methanosarcina thermophila, a nonmarine methanogenic archaebacterium, can grow in a range of saline concentrations. At less than 0.4 M NaCl, Ms. thermophila accumulated glutamate in response to increasing osmotic stress. At greater than 0.4 M NaCl, this organism synthesized a modified #beta#-amino acid that was identified as N"v"a"r"-"e"p"s"i"l"o"n-acetyl-#beta#-lysine by NMR spectroscopy and ion-exchange HPLC. This #beta#-amino acid derivative accumulated to high intracellular concentrations (up to 0.6 M) in Ms. thermophila and in another methanogen examined - Methanogenium cariaci, a marine species. The compound has features that are characteristic of a compatible solute: it is neutrally charged at physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological pH and it is highly soluble. When the cells were grown in the presence of exogenous glycine betaine, a physiological compatible solute, ...

International Nuclear Information System (INIS)

Addition of Gadolinium Nitrate as chemical shim to moderator heavy water of 540 MWe PHWR, at 15 mg/kg level (at a pH of 5.0) is practiced for reactor shutdown purposes. Presently a strong acid cation exchanger column is used for this purpose. During this operation, the moderator pH of 3.8, with the IX column outlet pH of ?3.5-3.6 was observed against the technical specification demand that when Gd is present, the pH of moderator must be in the range of 5.0-5.5. In order to achieve an iso-pH regime during Gd removal, studies were conducted using a mixed bed of strong acid cation resin plus a weak base anion resin (loaded in the volume ratio of 1 : 6), backed up in the same column (bottom most layer) by a 5 % nitric acid loaded weak base resin and topped by a strong acid cation resin (uppermost layer) simulating system flow velocity and percentage loading of resin. Using such a column it is demonstrated that Gd removal could be achieved simultaneously maintaining the water chemistry ...

International Nuclear Information System (INIS)

Nitric acid leaching from the weak base anion (WBA) exchanger had been evaluated and based on this a 5% mixture of nitric acid loaded weak base anion exchanger with fresh weak base anion exchanger (NLWBA) at the bottom of the ion exchange column has been devised to maintain an outlet pH in the range of 5.0 to 5.5 during Gd removal from the moderator system of TAPP - 3 and 4. A three layered bed had been constituted wherein strong acid cation (SAC) exchanger is placed as the top layer while a mixed bed of SAC and WBA or pure WBA is used as the middle layer and the 5% NLWBA was used as the bottom most layer. This bed configuration would result in an iso-pH regime in the moderator system during the Gd removal along with quantitative removal of Gd. Two three-layer bed columns were prepared at TAPS - 3 and 4 in July 07. The resin was loaded in batches and after preparing the column, the column was deuterated with heavy water (> 99.75 % w/w) at a ...

International Nuclear Information System (INIS)

At the Borssele Nuclear Power Station, which has been in operation since 1973, a comprehensive program of modifications, one of the most extensive of its kind worldwide, was conducted in 1997 within the framework of an integral safety evaluation carried out at ten-year intervals, especially in the nuclear section. The collective dose associated with this activity was greatly reduced by Alara measures, one of which was chemical decontamination of part of the emergency and residual heat removal systems. An average decontamination factor (DF) of 17 was achieved by using the Siemens Cord UV process. Two decontamination cycles were required. The decontamination program took three days to be completed. The planned collective dose was reduced from 1029 mSv (without decontamination) to 335 mSv (on the basis of a DF of 8). Based on the DF of 17 achieved, the planned dose was corrected downward to 270 mSv. The dose finally achieved was 118 mSv. A total of 13.7 kg of metal and 1.8 . 10"1"1 Bq of ...

Energy Technology Data Exchange (ETDEWEB)

The development of crud removal technology has started with the finding of the resin aging effect that an old ion exchange resin, aged by long year of use in the condensate demineralizer, had an enhanced crud removal capability. It was confirmed that some physical properties such as specific surface area and water retention capacity were increased due to degradation caused by long year of contact with active oxygens in the condensate water. So, it was speculated that those degradation in the resin matrix enhanced the adsorption of crud particulate onto the resin surface, hence the crud removal capability. Based on this, crud removal resin with greater surface area was first developed. This resin has shown an excellent crud removal efficiency in an actual power plant, and the crud iron concentration in the condensate effluent was drastically reduced by this application. However, the cross-linkage of the cation resin had to be lowered in a ...

Energy Technology Data Exchange (ETDEWEB)

Sorption studies of cesium, strontium, and cobalt (Cs, Sr, and Co) on bentonite under various experimental conditions, such as contact time, pH, sorbent and sorbate concentration, and temperature, have been performed. The sorption data for all these metals have been interpreted in terms of Freundlich, Langmuir, and Dubinin-Radushkevich equations. Thermodynamics parameters, such as heat of sorption {Delta}H{degrees}, free energy change {Delta}G{degrees}, and entropy change {Delta}S{degrees}, for the sorption of these metals on bentonite have been calculated. The value of {Delta}H{degrees} shows that the sorption of Cs was exothermic, while the sorption of Sr and Co on bentonite were endothermic in nature. The value of {Delta}G{degrees} for their sorption was negative, showing the spontaneity of the process. The maximum loading capacity of Cs, Sr, and Co were 75.5, 22, and 27.5 meq, respectively, for 100 g of bentonite. The mean free energy E of Cs, Sr, and Co sorption on bentonite was ...

Energy Technology Data Exchange (ETDEWEB)

A membrane process utilizing dialysis and selective complexation by water-soluble polymers has been developed. This process, termed affinity dialysis, has been shown to be selectively extract and concentrate both cations and anions in a manner similar to ion exchange or solvent extraction. The selective removal of calcium from sodium with selectivity of about 30, removal of chromate ion from dilute streams, and separation of transition metal ions such as Cu/Fe and Cu/Zn have all been successfully demonstrated. Effects of different polymers, polymer concentration, temperature, and flow rates have been studied. The effect of increased polymer concentration is to increase product concentration if appropriate changes in feed, polymer solution, and strip flow rates are made. A continuous polymer solution recycle and regeneration system has been constructed and operated with Cu/Zn and chromate/chloride feed streams. Removal of over 95% of the desired ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this report is to review the different technologies for trapping the gaseous wastes containing Cs, Ru, Tc, {sup 14}C, Kr, Xe, I and {sup 3}H from a voloxidation process. Based on literature reviews and KAERI's experimental results on the gaseous fission products trapping, appropriate trapping method for each fission product has been selected considering process reliability, simplicity, decontamination factor, availability, and disposal. Specifically, the most promising trapping method for each fission product has been proposed for the development of the INL off-gas trapping system. A fly ash filter is proposed as a trapping media for a cesium trapping unit. In addition, a calcium filter is proposed as a trapping media for ruthenium, technetium, and {sup 14}C trapping unit. In case of I trapping unit, AgX is proposed. For Kr and Xe, adsorption on solid is proposed. SDBC (Styrene Divinyl Benzene Copolymer) is also proposed as a conversion ...

International Nuclear Information System (INIS)

Polypeptides, copolymers of #alpha#-amino acids and #alpha#-hydroxy acids, could prove to be a valuable new class of synthetic biodegradable polymers. In this paper. steps in synthesis of poly (dl-lactide-co-3, 6-dimethylmorpholine-2,5-dione) from dl-lactide and dl-3,6-dimethylmorpholine-2,5-dione was explained. dl-Lactide was synthesized from lactic acid. In the reaction of 2-bromopropionyl chloride and dl-alanine, N-(2-bromopropionyl)-dl-alanine was prepared and this material was converted to its salt and finally this salt was converted to 3,6-dimethylmorpholine-2,5-dione in a sublime r. These two monomers, that is d l-lactide and dl-3,6-dimethylmorpholine-2,5-dione was polymerized by ring-opening polymerization. F T-IR, "1H NMR, "1"3C NMR Spectra were used for structure elucidation of all intermediate compounds and final product.

Energy Technology Data Exchange (ETDEWEB)

Products having balanced melting point and decomposition temperature have been developed by employing nylon 6T fundamental molecular structure and selected copolymer components, Arlen being one of the products. It has heat resistance as good as that of super-engineering plastics, low water absorption, and excellent cost-performance which can be used for normal injection molding machines. The unit price per kilogram is low when its high heat resistance is taken into consideration. The coefficient of water absorption is as low as about 1/3 of that of nylon 66, and it can be considered to be a low water absorbing amide. The molding temperature is from 320[degree]C to 350[degree]C, the decomposition temperature is 395[degree]C at 2% weight decreasing temperature, and normal injection molding can be employed. It has excellent soldering resistance, high temperature rigidity, dimensional stability, water absorbing coefficient, as well as good chemical resistance and ...

Energy Technology Data Exchange (ETDEWEB)

Langmuir-Blodgett films have been made with 3-n-hexadecylpyrrole and 3-n-octadecylpyrrole monomers and copolymers with unsubstituted pyrrole made by chemical polymerization at the air-water interface on a subphase containing FeCl/sub 3/. Langmuir-Blodgett films consisting of mixtures of stearic acid and alkylsubstituted polythiophenes have also been made as bilayer films. The orientation of single and multilayer films on platinum substrates have been studied by Near Edge X-ray Absorption Fine Structure Spectroscopy which also gives information about charge transfer interactions between the aromatic groups and the metallic substrates. The alkylsubstituted pyrroles form highly ordered two-dimensional structures. FeCl/sub 3/ initiated copolymerization with unsubstituted pyrrole leads to a more disordered system. In the case of polythiophene-stearic acid bilayers, the stearic acid layers are highly ordered. The poly(alkyl thiophene) layers sandwiched between stearic ...

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 oxidation in which the double layer structure was not formed and ...

Energy Technology Data Exchange (ETDEWEB)

Concerning high performance composite solid propellant BAMO and BAMO-based copolymers, synthetic method and properties of them were studied. Comparison graph of theoretical specific impulse for various propellants were shown, by that, reason why highest specific impulse BAMO was selected as direction of the study. As the orientation of synthesis, those were indicated that radicals at both ends should be hydroxyl so as urethane bonding was available, that liquid at normal temperature was required for easy handling, and that glass transition temperature is required to be low enough. Synthesis was conducted by ring-opening polymerization of ring ether detail procedures of which were explained. Measurements of properties was performed for thermochemical properties, thermal decomposition, combution heat, and friction sensitivity test to confirm safety. As the result, those were understood that thermal decomposition was divided into two phases, rapid exothermal ...

Energy Technology Data Exchange (ETDEWEB)

Independent isomeric yield ratios of {sup 131}Te, {sup 133}Te and {sup 134}I have been determined at five different energies in the range of 25-44 MeV alpha particle induced fission of {sup 238}U using radiochemical and gamma spectrometric techniques. From the independent isomeric yield ratios, fragment angular momenta (J{sub rms}) have been deduced using a statistical model analysis. The J{sub rms} were also calculated theoretically based on thermal equilibration of various collective modes after considering the occurrence of multichance fission. These data and the literature data for various fragments in the mass region 126-136 in {sup 238}U ({alpha},f), {sup 238}U (p,f) and {sup 238}U ({gamma},f) show the following important features: (i) Both the entrance channel excitation energy and input angular momentum affect the fragment angular momentum in the exit channel. (ii) There are two groups of fission products from the point of view of change of fragment angular ...

Energy Technology Data Exchange (ETDEWEB)

One of the aims in the safety assessment of SFR-1 is to estimate the release to the environment. In order to make these calculations there is a need to describe the inventory in greater detail. The new computerised database of waste in SFR-1 gives a good possibility to achieve this. The aim for project SAFE is to make both conservative and realistic radionuclide transport calculations. To achieve this goal there must be two inventories. The conservative inventory is the inventory used in the design of the repository, which in most parts is identical with the limits in the licence for SFR-1. There is a great interest to have good estimates of the volumes of the different waste types. A thorough prognosis should be made in 1999, but until then the latest one from 1995 could be used in the calculations. The total (actual) inventory of nuclides is calculated from the measurements of the easy-to-measure nuclides since, in principle, all hard-to-measure nuclides are calculated by correlation ...

Science.gov (United States)

Novel in situ polymerizable liquid three-arm biodegradable oligomeric polyesters based upon glycolic acid (GA), L-lactic acid (LLA), and their copolymers are synthesized and characterized. Injectable and in situ curable polymer neat resins and their composites formulated with bioabsorbable beta-tricalcium phosphate are prepared at room temperature using photo- and redox-initiation systems, respectively. The cured neat resins show the initial compressive yield strength (YCS, MPa), modulus (M, MPa), ultimate compressive strength (UCS, MPa), and toughness (T, kN mm), ranging from 4.0 to 20.1, 201.5 to 730.2, 82.7 to 310.5, and 1.02 to 3.93. The cured composites show the initial YCS, M, UCS and T, ranging from 27.7 to 56.4, 1440 to 4870, 81.6 to 158.9, and 0.94 to 1.97. Increasing GA/LLA ratio increases all the initial compressive strengths of both neat resins and composites. Increasing filler content increases YCS and M but decreases UCS and T. A diametral tensile ...

Energy Technology Data Exchange (ETDEWEB)

To improve adherent properties of electrogalvanized steel (EGS) to polymeric topcoats, the surfaces of EGS were modified by polyelectrolyte-modified zinc phosphating solution. The electrochemical reaction between phosphating solution and EGS led to the complete coverage with fully grown hopeite crystals after only 5 sec treatment, thereby improving adhesion to topcoating and providing protection of EGS against corrosion. To evaluate the ability of polyphenylene sulfide (PPS) polyaryl thermoplastic coatings to protect zinc phosphate (Zn{center_dot}Ph)treated steels from corrosion in a wet, harsh environment ( 1.0 wt % H{sub 2}SO{sub 4}, 3.0 wt % NaCl and 96.0 wt % water at temperatures from 25{degrees} to 200{degree}C), we exposed them in an autoclave to attempt heating-cooling cyclic fatigue tests (1 cycle = 12 hr at 200{degrees}C + 12 hr at 25{degrees}C) up to 90 times. The major chemical reaction at the interface between the PPS and Zn in the Zn-Ph layer during cycling led to the ...