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Sample records for irradiated solid egg-white

  1. Quality Properties of Cakes Containing Gamma-Irradiated Egg White

    International Nuclear Information System (INIS)

    Lee, J.W.; Seo, J.H.; Ahn, H.J; Byun, M.W; Kim, Y.H.; Choi, J.M.; Yook, H.S.

    2003-01-01

    As a research on the practical approaches of gamma irradiation for the reduction of egg allergy, cakes including gamma-irradiated egg white were manufactured, and rheological characteristics and sensory qualities of the cakes were evaluated. Egg white was separated from whole egg and then gamma-irradiated with the absorbed dose of 10 or 20 kGy

  2. Study on the sterilization of egg white powder by irradiation

    International Nuclear Information System (INIS)

    Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Pei Ying

    2011-01-01

    The article studied the killing microorganism result, the influence of main essential nutrient and sense organ of egg white powder by Co-60 γ-ray irradiation. The microorganism index of the egg white powder samples can meet the government food 1 sanitation standard by 4 kGy irradiation, and the killing microorganism rare can reach 100%. The irradiation dose from 4 to 10 kGy has little influence to the egg white powder protein, crude fiber and amino acids contrasting to comparison, and the sensory quality such as color and luster, scent has little change below 6 kGy irradiation. Compositing the result of physical chemistry and sense organ, the optimal irradiation dose of egg white powder killing microorganism is 4 to 6 kGy. (authors)

  3. Study on the sterilization of egg white powder by irradiation

    International Nuclear Information System (INIS)

    Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Wang Zhidong

    2013-01-01

    The sterilizing effect, influence on main essential nutrient and sensory qualities of egg white powder treated with 60 Co γ-ray irradiation were studied. The microorganism index of egg white powder samples treated with 4 kGy irradiation could meet the government food sanitation standard, and the sterilization rate could reach 100%. The irradiation doses from 4 to 10 kGy had little influence on egg white powder protein, crude fiber and amino acidscontent, and the sensory quality such as color, luster, and scent changed little below 6 kGy irradiation. Considering the result of this study, the optimal irradiation dose for egg white powder sterilization was 4 to 6 kGy. (authors)

  4. Study on the sterilization of egg white powder by irradiation

    International Nuclear Information System (INIS)

    Fu Lixin; Meng Lifen; Zhao Xiaonan; Xu Dechun; Hu Shaoxin; Chen Changdong; Pei Ying

    2012-01-01

    The article studied the killing microorganism result, the influence of main essential nutrient and sense organ of egg white powder by Co-60 γ-ray irradiation. The microorganism index of the egg white powder samples can meet the government food sanitation standard by 4 kGy irradiation, and the killing microorganism rare can reach 100%. The irradiation dose from 4 to 10 kGy has little influence to the egg white powder protein, crude fiber and amino acids contras ting to comparison, and the sensory quality such as color and luster, scent has little change below 6 kGy irradiation. Synthesizing the results of physical chemistry and sense organ, the optimal irradiation dose of egg white powder killing microorganism is 4 to 6 kGy. (authors)

  5. Fourier transform infrared studies in solid egg white lysozyme

    International Nuclear Information System (INIS)

    Rivzi, T.Z.

    1994-12-01

    Fourier Transform Infrared (FTIR) Spectroscopy is the most recent addition to the arsenal of bioanalytical techniques capable of providing information about the secondary structure of proteins in a variety of environments. FTIR spectra have been obtained in solid egg white lysozyme. The spectra display the usual amide I, II and III bands. Secondary structural information obtained from the spectra after applying resolution enhancement techniques to the amide I band has been found consistent with the x-ray crystallographic data of the protein and also to the spectroscopic data of the protein in aqueous solution. (author). 17 refs, 6 figs, 2 tabs

  6. Irradiation of shell egg on the physicochemical and functional properties of liquid egg white.

    Science.gov (United States)

    Min, B; Nam, K C; Jo, C; Ahn, D U

    2012-10-01

    This study was aimed at determining the effect of irradiation of shell eggs on the physiochemical and functional properties of liquid egg white during storage. Color and textural parameters of irradiated liquid egg white after cooking were also determined. Shell eggs were irradiated at 0, 2.5, 5, or 10 kGy using a linear accelerator. Egg white was separated from yolk and stored in at 4°C up to 14 d. Viscosity, pH, turbidity, foaming properties, color, and volatile profile of liquid egg white, and color and texture properties of cooked egg white were determined at 0, 7, and 14 d of storage. Irradiation increased the turbidity but decreased viscosity of liquid egg white. Foaming capacity and foam stability were not affected by irradiation at lower dose (2.5 kGy), but were deteriorated at higher doses (≥5.0 kGy) of irradiation. Sulfur-containing volatiles were generated by irradiation and their amounts increased as the irradiation dose increased. However, the sulfur volatiles disappeared during storage under aerobic conditions. Lightness (L* value) and yellowness (b* value) decreased, but greenness (-a* value) increased in cooked egg white in irradiation dose-dependent manners. All textural parameters (hardness, adhesiveness, cohesiveness, chewiness, and resilience) of cooked egg white increased as the irradiation dose increased, but those changes were marginal. Our results indicated that irradiation of shell egg at lower doses (up to 2.5 kGy) had little negative impact on the physiochemical and functional properties of liquid egg white, but can improve the efficiency of egg processing due to its viscosity-lowering effect. Therefore, irradiation of shell eggs at the lower doses has high potential to be used by the egg processing industry to improve the safety of liquid egg without compromising its quality.

  7. Improvement of foaming ability of egg white product by irradiation and its application

    Science.gov (United States)

    Song, Hyun-Pa; Kim, Binna; Choe, Jun-Ho; Jung, Samooel; Kim, Kyong-Su; Kim, Dong-Ho; Jo, Cheorun

    2009-03-01

    To investigate the enhancement of foaming abilities of liquid egg white (LEW) and egg white powder (EWP) by irradiation and its application for bakery product, LEW and EWP were irradiated at 0, 1, 2, and 5 kGy by Co-60 gamma ray. There was no pH change found among treatments in both LEW and EWP. The viscosity of LEW decreased significantly by irradiation ( Pcake baked with irradiated LEW were significantly higher than those of unirradiated control ( Pcake were greater at 2 kGy only than those of control. A significant decrease in hardness, chewiness, and gumminess values and an increase in Hunter L* value were observed in the angel cakes prepared from irradiated egg white products ( P<0.05). Results indicated that irradiation of egg white could offer advantages in increasing foaming ability and improving quality of final bakery products.

  8. Liquid egg white pasteurization using a centrifugal UV irradiator.

    Science.gov (United States)

    Geveke, David J; Torres, Daniel

    2013-03-01

    Studies are limited on UV nonthermal pasteurization of liquid egg white (LEW). The objective of this study was to inactivate Escherichia coli using a UV irradiator that centrifugally formed a thin film of LEW on the inside of a rotating cylinder. The LEW was inoculated with E. coli K12 to approximately 8 log cfu/ml and was processed at the following conditions: UV intensity 1.5 to 9.0 mW/cm²; cylinder rotational speed 450 to 750 RPM, cylinder inclination angle 15° to 45°, and flow rate 300 to 900 ml/min, and treatment time 1.1 to 3.2s. Appropriate dilutions of the samples were pourplated with tryptic soy agar (TSA). Sublethal injury was determined using TSA+4% NaCl. The regrowth of surviving E. coli during refrigerated storage for 28 days was investigated. The electrical energy of the UV process was also determined. The results demonstrated that UV processing of LEW at a dose of 29 mJ/cm² at 10°C reduced E. coli by 5 log cfu/ml. Inactivation significantly increased with increasing UV dose and decreasing flow rate. The results at cylinder inclination angles of 30° and 45° were similar and were significantly better than those at 15°. The cylinder rotational speed had no significant effect on inactivation. The occurrence of sublethal injury was detected. Storage of UV processed LEW at 4° and 10°C for 21 days further reduced the population of E. coli to approximately 1 log cfu/ml where it remained for an additional 7 days. The UV energy applied to the LEW to obtain a 5 log reduction of E. coli was 3.9 J/ml. These results suggest that LEW may be efficiently pasteurized, albeit at low flow rates, using a nonthermal UV device that centrifugally forms a thin film. Published by Elsevier B.V.

  9. Chemical changes of proteins of irradiated egg-white

    International Nuclear Information System (INIS)

    Hajos, G.; Kiss, I.; Halasz, A.

    1990-01-01

    The effect of ionizing radiation (Co-60) was studied on egg-white proteins. Our earlier study revealed that the functional properties of egg-white depend on the dose of radiation and 3 kGy was found as optimal from the microbiological point of view. The effect of radiation on the protein structure was investigated in the dose range of 0-12 kGy using SDS polyacrylamide gel electrophoresis. The effect of this treatment was compared in fresh, frozen, and freeze-dried samples and in a 1% aqueous solution of egg-white. In aqueous solution a very important change was a marked formation of aggregates induced by radiation at doses of 1.5, 6.0 and 12.0 kGy. The effect of radiation was found to be much smaller in the freeze-dried and frozen samples. Electrophoretic investigations suggest the formation of radiation-induced aggregates, whereas effects in fresh egg-white were much smaller. (author)

  10. Effect of Irradiation on the Mixture of Egg White Proteins Responsible for Foaming Property

    International Nuclear Information System (INIS)

    Xian De Liu; Rong Xiu Han; Dong-Il Jin; Soo-Kee Lee; Cheo-Run Jo

    2009-01-01

    Irradiation of egg white increased foaming ability significantly. To investigate the protein modification by irradiation responsible for the increase of foaming ability, 3 major egg white proteins were purchased and mixed (7.7 g/L ovalbumin, 1.8 g/L ovotransferrin, 0.5 g/L lysozyme) as a model system and irradiated at 0, 2.5, and 5 kGy. The different protein expressions were evaluated using 2-D electrophoresis and it was found that ovotransferrin was cleaved by irradiation and molecular weight and isoelectric point were changed. In addition, many uncharacterized proteins were found and it indicated that irradiation modified proteins randomly but mainly fragmentation was observed. Therefore, it can be concluded that protein fragmentation of 3 major egg white proteins responsible for foaming ability may be the main reason for the improvement of foaming ability

  11. Improvement of foaming ability of egg white product by irradiation and its application

    International Nuclear Information System (INIS)

    Song, Hyun-Pa; Kim, Binna; Choe, Jun-Ho; Jung, Samooel; Kim, Kyong-Su; Kim, Dong-Ho; Jo, Cheorun

    2009-01-01

    To investigate the enhancement of foaming abilities of liquid egg white (LEW) and egg white powder (EWP) by irradiation and its application for bakery product, LEW and EWP were irradiated at 0, 1, 2, and 5 kGy by Co-60 gamma ray. There was no pH change found among treatments in both LEW and EWP. The viscosity of LEW decreased significantly by irradiation (P<0.05), whereas that of EWP was not affected by irradiation. The foaming ability of LEW and EWP was significantly increased by irradiation as a dose-dependent manner (P<0.05). The volume and the height of angel cake baked with irradiated LEW were significantly higher than those of unirradiated control (P<0.05). For EWP, the volume and the height of angel cake were greater at 2 kGy only than those of control. A significant decrease in hardness, chewiness, and gumminess values and an increase in Hunter L* value were observed in the angel cakes prepared from irradiated egg white products (P<0.05). Results indicated that irradiation of egg white could offer advantages in increasing foaming ability and improving quality of final bakery products

  12. The effect of irradiation on the functional properties of spray-dried egg white protein

    International Nuclear Information System (INIS)

    Clark, D.C.; Kiss, I.F.; Wilde, P.J.; Wilson, D.R.

    1992-01-01

    The foaming properties of spray-dried egg white powder were examined as a function of dosage with ionizing radiation. Foam stability was studied by a micro-conductimetric method. A marked increase in foam stability was observed in all the irradiated samples examined (2–16 kGy) when compared to a non-irradiated control. The drainage rate and minimum thickness of air-suspended thin liquid films stabilised with egg white protein was measured interferometrically. The rate of film thinning decreased with increasing dose suggesting a dose related change in the bulk viscosity. There were minor changes in the secondary and tertiary structure of the irradiated protein determined by circular dichroism, which may account for the observed changes in functionality

  13. 21 CFR 160.145 - Dried egg whites.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dried egg whites. 160.145 Section 160.145 Food and... CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.145 Dried egg whites. (a) The food dried egg whites, egg white solids, dried egg albumen, egg albumen solids is...

  14. Changes of the antigenic and allergenic properties of a hen's egg albumin in a cake with gamma-irradiated egg white

    International Nuclear Information System (INIS)

    Lee, J.-W.; Seo, J.-H.; Kim, J.-H.; Lee, S.-Y.; Kim, K.-S.; Byun, M.-W.

    2005-01-01

    Changes of the antigenicity and allergenicity of a hen's egg albumin (ovalbumin, OVA) in white layer cakes containing egg white gamma-irradiated with 10 or 20 kGy were monitored by an enzyme-linked immunosorbent assay (ELISA), individually formatted with mouse anti-OVA IgG (mouse IgG) and with egg allergic patients' IgE. Mouse IgG recognized OVA in the cakes with irradiated egg white better than that in the control with a non-irradiated one. Whereas, the detected concentrations of intact OVA in the control significantly decreased in the treatments, when determined by IgE-based ELISA. The results appeared to indicate that the antigenicity of the OVA increased, but that the allergenicity was decreased by irradiation and processing. Egg white irradiated for reducing the egg allergy could be used for producing a safer cake from the egg allergy

  15. Changes of the antigenic and allergenic properties of a hen's egg albumin in a cake with gamma-irradiated egg white

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.-W.; Seo, J.-H.; Kim, J.-H.; Lee, S.-Y.; Kim, K.-S.; Byun, M.-W. E-mail: mwbyun@nanum.kaeri.re.kr

    2005-04-01

    Changes of the antigenicity and allergenicity of a hen's egg albumin (ovalbumin, OVA) in white layer cakes containing egg white gamma-irradiated with 10 or 20 kGy were monitored by an enzyme-linked immunosorbent assay (ELISA), individually formatted with mouse anti-OVA IgG (mouse IgG) and with egg allergic patients' IgE. Mouse IgG recognized OVA in the cakes with irradiated egg white better than that in the control with a non-irradiated one. Whereas, the detected concentrations of intact OVA in the control significantly decreased in the treatments, when determined by IgE-based ELISA. The results appeared to indicate that the antigenicity of the OVA increased, but that the allergenicity was decreased by irradiation and processing. Egg white irradiated for reducing the egg allergy could be used for producing a safer cake from the egg allergy.

  16. Pulse radiolysis study of egg white

    International Nuclear Information System (INIS)

    Micic, O.I.; Josimovic, L.; Markovic, V.

    1978-01-01

    Radiolytic processes in egg white in intervals of 0.1μs to several seconds have been studied by the pulse radiolysis technique. The formation and decay of short-lived intermediates and their absorption spectra were observed under varied experimental conditions. The results show that intermediates are produced predominantly in reactions of radicals formed in water radiolysis with egg white proteins. The intermediates decay mainly in the first-order intermolecular processes, though the mechanism of transformations is very complex. (author)

  17. Pepsin Egg White Hydrolysate Ameliorates Obesity-Related Oxidative Stress, Inflammation and Steatosis in Zucker Fatty Rats.

    Directory of Open Access Journals (Sweden)

    M Garcés-Rimón

    Full Text Available The aim of this work was to evaluate the effect of the administration of egg white hydrolysates on obesity-related disorders, with a focus on lipid metabolism, inflammation and oxidative stress, in Zucker fatty rats. Obese Zucker rats received water, pepsin egg white hydrolysate (750 mg/kg/day or Rhizopus aminopeptidase egg white hydrolysate (750 mg/kg/day for 12 weeks. Lean Zucker rats received water. Body weight, solid and liquid intakes were weekly measured. At the end of the study, urine, faeces, different organs and blood samples were collected. The consumption of egg white hydrolysed with pepsin significantly decreased the epididymal adipose tissue, improved hepatic steatosis, and lowered plasmatic concentration of free fatty acids in the obese animals. It also decreased plasma levels of tumor necrosis factor-alpha and reduced oxidative stress. Pepsin egg white hydrolysate could be used as a tool to improve obesity-related complications.

  18. 21 CFR 160.150 - Frozen egg whites.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen egg whites. 160.150 Section 160.150 Food... HUMAN CONSUMPTION EGGS AND EGG PRODUCTS Requirements for Specific Standardized Eggs and Egg Products § 160.150 Frozen egg whites. (a) Frozen egg whites, frozen egg albumen is the food prepared by freezing...

  19. Observations of the "egg white injury" in ants.

    Directory of Open Access Journals (Sweden)

    Laure-Anne Poissonnier

    Full Text Available A key determinant of the relationship between diet and longevity is the balance of protein to carbohydrate in the diet. Eating excess protein relative to carbohydrate shortens lifespan in solitary and social insects. Here we explored how lifespan and behavior in ants was affected by the quality of protein ingested and the presence of associated antinutrients (i.e. compounds that interfere with the absorption of nutrients. We tested diets prepared with either egg white protein only or a protein mixture. Egg white contains an anti-nutrient called avidin. Avidin binds to the B vitamin biotin, preventing its absorption. First, we demonstrate that an egg-white diet was twice as deleterious as a protein-mixture diet. Second, we show that ingestion of egg-white diet drastically affected social behavior, triggering elevated levels of aggression within the colony. Lastly, we reveal that by adding biotin to the egg white diet we were able to lessen its detrimental effects. This latest result suggests that ants suffered biotin deficiency when fed the egg white diet. In conclusion, anti-nutrients were known to affect health and performance of animals, but this is the first study showing that anti-nutrients also lead to severe changes in behavior.

  20. Studies on the irradiated solids

    International Nuclear Information System (INIS)

    Lesueur, D.

    1988-01-01

    The 1988 progress report of the Irradiated Solids laboratory (Polytechnic School, France), is presented. The Laboratory activities concern the investigations on disordered solids (chemical or structural disorder). The disorder itself, its effects on the material physical properties and the particle-matter interactions, are investigated. The research works are performed in the following fields: solid state physics, irradiation and stoechiometric defects, and nuclear materials. The scientific reviews, the congress communications and the thesis are listed [fr

  1. Proteomics analysis of egg white proteins from different egg varieties.

    Science.gov (United States)

    Wang, Jiapei; Liang, Yue; Omana, Dileep A; Kav, Nat N V; Wu, Jianping

    2012-01-11

    The market of specialty eggs, such as omega-3-enriched eggs, organic eggs, and free-range eggs, is continuously growing. The nutritional composition of egg yolk can be manipulated by feed diet; however, it is not known if there is any difference in the composition of egg white proteins among different egg varieties. The purpose of the study was to compare the egg white proteins among six different egg varieties using proteomics analysis. Egg white proteins were analyzed using two-dimensional gel electrophoresis (2-DE), and 89 protein spots were subjected to LC-MS/MS. A total of 23 proteins, belonging to Gallus gallus , were identified from 72 detected protein spots. A quiescence-specific protein precursor in egg white was identified for the first time in this study. Significant differences in the abundant levels of 19 proteins (from 65 protein spots) were observed among six egg varieties. Four proteins, ovalbumin-related protein Y, cystatin, avidin, and albumin precursor, were not different among these six egg varieties. These findings suggest that the abundance, but not the composition, of egg white proteins varied among the egg varieties.

  2. Formation of lysinoalanine in egg white under alkali treatment.

    Science.gov (United States)

    Zhao, Yan; Luo, Xuying; Li, Jianke; Xu, Mingsheng; Tu, Yonggang

    2016-03-01

    To investigate the formation mechanism of lysinoalanine (LAL) in eggs during the alkali treatment process, NaOH was used for the direct alkali treatment of egg white, ovalbumin, and amino acids; in addition, the amount of LAL formed during the alkali treatment process was measured. The results showed that the alkali treatment resulted in the formation of LAL in the egg white. The LAL content increased with increasing pH and temperature, with the LAL content first increasing and then leveling off with increasing time. The amount of LAL formed in the ovalbumin under the alkali treatment condition accounted for approximately 50.51% to 58.68% of the amount of LAL formed in the egg white. Thus, the LAL formed in the ovalbumin was the main source for the LAL in the egg white during the alkali treatment process. Under the alkali treatment condition, free L-serine, L-cysteine, and L-cystine reacted with L-lysine to form LAL; therefore, they are the precursor amino acids of LAL formed in eggs during the alkali treatment process. © 2016 Poultry Science Association Inc.

  3. Determination of o-tyrosine in shrimps, fish, mussels and egg-white

    International Nuclear Information System (INIS)

    Meier, W.; Hediger, H.; Artho, A.; Meier, E.J.M.

    1993-01-01

    With this new HPLC-system the o-tyrosine in irradiated shrimps, fish, mussels and egg-white is very well separated from other peaks in the chromatogram. It is not any more necessary to freeze dry the samples. Samples with an amount of o-tyrosine greater than 0.1 mg/kg are suspect. To confirm such results, the o-tyrosine fraction can be collected and the o-tyrosine can be determined either by GC/MS after derivatisation with chloro-formicacid-methylester or by a second HPLC-step using a cation exchange column. (orig./vhe)

  4. A study of the factors affecting the foaming properties of egg white - a review

    International Nuclear Information System (INIS)

    Lomakina, K.; MÍKOVÁ, K.

    2006-01-01

    Many foods are prepared using egg white, most of them being based on the foaming properties of egg white which are due to albumen proteins ability to encapsulate and retain air. Therefore, many scientists aim to find new methods to improve the volume and the stability of egg white foam. This paper is a review of various factors affecting the foaming ability of egg white

  5. Gamma-radiation induced damage of proteins in the thick fraction of egg white

    Directory of Open Access Journals (Sweden)

    MARIJA VUCKOVIC

    2005-11-01

    Full Text Available The thick fraction of egg white saturated with either N2O or Ar was irradiated in the dose range 1.5–45 kGy at 60Co gamma source. The gel structure decomposition and other processes accompanied with changes in protein molecular mass were followed by Sephadex G-200 exclusion chromatography, denaturing SDS-polyacrylamide gel electrophoresis, viscosity and turbidity measurements. The complex behaviour of viscosity was observed in the N2O saturated sample (where the hydrated electron was converted into the OH radical; the initial abrupt decrease that radually slows down reaching the minimum at 12 kGy (hmin = 2.7 mPa s followed by the slow rise was measured. The Ar saturated sample ([eaq-] ~ [OH] showed both the significantly faster initial decrease and lower viscosity minimum (hmin = 2.2 mPa s. The combined Sephadex G-200 exclusion chromatography and denaturing SDS-polyacrylamide gel electrophoresis data revealed that the three-dimensional egg white (hydrated gel structure was (efficiently decomposed even in the N2O saturated sample. The protein scission was detected in the entire dose range studied, while the protein agglomeration is not noticed at low doses (around 1.5 kGy; however, it dominates at higher doses. In the highest dose region studied, the loss of structure in SDS-PAGE chromatograms indicates that the agglomerates are formed from protein fragments rather than from intact proteins. The continuous linear increase in turbidity was measured. The results obtained indicate that ionizing radiation causes the breakdown of the protein network of the thick fraction of egg white via the reduction of S–S bridges by the hydrated electron and the protein fragmentation due to the direct action of ionizing radiation. The protein agglomeration is initiated by the reaction of the OH radical; its inefficiency at low doses is attributed to the glucose antioxidant properties and radical immobility.

  6. Quality characteristic of spray-drying egg white powders.

    Science.gov (United States)

    Ma, Shuang; Zhao, Songning; Zhang, Yan; Yu, Yiding; Liu, Jingbo; Xu, Menglei

    2013-10-01

    Spray drying is a useful method for developing egg process and utilization. The objective of this study was to evaluate effects on spray drying condition of egg white. The optimized conditions were spraying flow 22 mL/min, feeding temperature 39.8 °C and inlet-air temperature 178.2 °C. Results of sulfydryl (SH) groups measurement indicated conformation structure have changed resulting in protein molecule occur S-S crosslinking phenomenon when heating. It led to free SH content decreased during spray drying process. There was almost no change of differential scanning calorimetry between fresh egg white and spray-drying egg white powder (EWP). For a given protein, the apparent SH reactivity is in turn influenced by the physico-chemical characteristics of the reactant. The phenomenon illustrated the thermal denaturation of these proteins was unrelated to their free SH contents. Color measurement was used to study browning level. EWP in optimized conditions revealed insignificant brown stain. Swelling capacity and scanning electron micrograph both proved well quality characteristic of spray-drying EWP. Results suggested spray drying under the optimized conditions present suitable and alternative method for egg processing industrial implementation. Egg food industrialization needs new drying method to extend shelf-life. The purpose of the study was to provide optimal process of healthy and nutritional instant spray-drying EWP and study quality characteristic of spray-drying EWP.

  7. NAA Comparison of Nutriens in Egg Yolk and Egg White

    International Nuclear Information System (INIS)

    Ruangdit, S.; Maijan, P.; Channuie, J.; Picha, R.

    2014-01-01

    Food we eat has significant effects on our wellbeing. Eggs are among food products widely consumed and contain many essential nutrients. Yet eggs often are involved in dietary controversy regarding benefit versus risk. The fear of serum cholesterol has driven a large number of people away from consuming egg yolks. In this study, we assessed the nutritional importance of eggs using instrumental neutron activation analysis (INAA) technique at Thai Research Reactor, operating at 1.2 MW. We investigated whether consumers miss any health benefits by choosing to eat only egg whites or yolks rather than whole natural eggs. Essential minerals such as sodium, potassium, manganese, magnesium, copper, selenium, iron and zinc are studied using three NAA loading methods: short-term individual pneumatic transfer system loading using inner-core tubes, medium-term CA3 loading and long-term Lazy Susan (LS) loading for 10 s, 7 h and 3 d, respectively. Two Standard Reference Materials (SRMs) were used to find the nutrient concentrations and validate the method. From the study, we found significant differences in nutritional contents between egg yolks and egg whites. Along with literature review conducted as part of this study, we evaluated the consumption choice when it comes to eggs.

  8. Separation of ovotransferrin and ovomucoid from chicken egg white.

    Science.gov (United States)

    Abeyrathne, E D N S; Lee, H Y; Ahn, D U

    2014-04-01

    Ovotransferrin and ovomucoid were separated using 2 methods after extracting the ovotransferrin- and ovomucoid-containing fraction from egg white. Diluted egg white (2×) was added to Fe(3+) and treated with 43% ethanol (final concentration). After centrifugation, the supernatant was collected and treated with either a high-level ethanol (61% final concentration) or an acidic salt combination (2.5% ammonium sulfate and 2.5% citric acid) to separate ovotransferrin and ovomucoid. For the high-level of ethanol method, ovotransferrin was precipitated using 61% ethanol. After centrifugation, the precipitant was dissolved in 9 vol. of distilled water and the residual ethanol in the solution was removed using ultrafiltration. The supernatant, mainly containing ovomucoid, was diluted with 4 vol. of water, had ethanol removed, and was then concentrated and used as the ovomucoid fraction. For the acidic salt precipitation method, the ethanol in the supernatant was removed first. The ethanol-free solution was then concentrated and treated with a 2.5% ammonium sulfate and 2.5% citric acid combination. After centrifugation, the precipitant was used as the ovotransferrin and the supernatant as the ovomucoid fraction. The ovomucoid fraction from both of the protocols was further purified by heating at 65°C for 20 min and the impurities were removed by centrifugation. The yields of ovomucoid and ovotransferrin were >96 and >92%, respectively. The purity of ovomucoid was >89% and that of the ovotransferrin was >88%. The ELISA results confirmed that the activity of the separated ovotransferrin was >95%. Both of the protocols separated ovotransferrin and ovomucoid effectively and the methods were simple, fast, and easy to scale up.

  9. Egg white-mediated green synthesis of silver nanoparticles with excellent biocompatibility and enhanced radiation effects on cancer cells

    Directory of Open Access Journals (Sweden)

    Lu RQ

    2012-04-01

    Full Text Available Renquan Lu1, Dapeng Yang2, Daxiang Cui2, Zhongyang Wang3, Lin Guo11Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, Shanghai, 2Department of Bio-Nano-Science and Engineering, National Key Laboratory of Nano/Micro Fabrication Technology, Key Laboratory for Thin Film and Microfabrication of Ministry of Education, Institute of Micro-Nano Science and Technology, Shanghai Jiao Tong University, Shanghai, 3College of Chemistry and Chemical Engineering, Yantai University, Shan Dong Province, People's Republic of ChinaAbstract: A simple, cost-effective, and environmentally friendly approach to the aqueous-phase synthesis of silver (Ag nanoparticles was demonstrated using silver nitrate (AgNO3 and freshly extracted egg white. The bio-conjugates were characterized by UV-visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and dynamic light scattering. These results indicated that biomolecule-coated Ag nanoparticles are predominantly spherical in shape with an average size of 20 nm. The proteins of egg white, which have different functional groups, played important roles in reducing Ag+ and maintaining product attributes such as stability and dispersity. In vitro cytotoxicity assays showed that these Ag-protein bio-conjugates showed good biocompatibility with mouse fibroblast cell lines 3T3. Furthermore, X-ray irradiation tests on 231 tumor cells suggested that the biocompatible Ag-protein bio-conjugates enhanced the efficacy of irradiation, and thus may be promising candidates for use during cancer radiation therapy.Keywords: green chemistry, biosynthesis, egg white, Ag nanoparticles, X-ray irradiation

  10. Effect of Proteolytic Modification on Texture and Mastication of Heat‐Treated Egg White Gels

    Science.gov (United States)

    Funaki, Junko; Minami, Michiko; Abe, Sachie; Ueda, Reiko; Eto, Wakako; Kugino, Kenji; Kugino, Mutsuko; Abe, Keiko; Toko, Kiyoshi

    2016-01-01

    Abstract Raw egg white undergoes sol–gel transition by heat treatment, which changes it to an elastic gel. Here, protease treatment to render a new texture to heated egg white gel was applied. Protease‐treated gels exhibited ductile flow without obvious rupture points. Transmission electron microscopy analysis showed that in protease‐treated gels, protein aggregates were distributed more homogeneously compared with that observed in the untreated control, probably because ovalbumin was digested into small peptides as revealed by SDS‐PAGE. The properties of the gel were evaluated by sensory tests and by measuring the movement of the masseter muscle, using surface electromyography. Results showed that maximum bite force and mastication duration were decreased for the protease‐treated gels, which were evaluated as being softer, smoother, less elastic and better textured. Overall, our results indicate that protease‐treated egg white gel has superior qualities and is easier to swallow than the untreated gel. Practical Applications In the food industry, the use of egg white is limited compared with that of egg yolk and whole eggs. In this study, we performed protease treatment to generate a new food material with smoother and softer texture compared with heat treated egg white. Our findings may expand the consumption of egg white, which can be consumed by people with mastication and swallowing disorders, and reduce the waste of egg white as a surplus product. PMID:28239213

  11. In-depth analysis of the chicken egg white proteome using an LTQ Orbitrap Velos

    Directory of Open Access Journals (Sweden)

    Mann Matthias

    2011-02-01

    Full Text Available Abstract Background Hen's egg white has been the subject of intensive chemical, biochemical and food technological research for many decades, because of its importance in human nutrition, its importance as a source of easily accessible model proteins, and its potential use in biotechnological processes. Recently the arsenal of tools used to study the protein components of egg white has been complemented by mass spectrometry-based proteomic technologies. Application of these fast and sensitive methods has already enabled the identification of a large number of new egg white proteins. Recent technological advances may be expected to further expand the egg white protein inventory. Results Using a dual pressure linear ion trap Orbitrap instrument, the LTQ Orbitrap Velos, in conjunction with data analysis in the MaxQuant software package, we identified 158 proteins in chicken egg white with two or more sequence unique peptides. This group of proteins identified with very high confidence included 79 proteins identified in egg white for the first time. In addition, 44 proteins were identified tentatively. Conclusions Our results, apart from identifying many new egg white components, indicate that current mass spectrometry technology is sufficiently advanced to permit direct identification of minor components of proteomes dominated by a few major proteins without resorting to indirect techniques, such as chromatographic depletion or peptide library binding, which change the composition of the proteome.

  12. A simple and reliable methodology to detect egg white in art samples

    Indian Academy of Sciences (India)

    2013-04-26

    Apr 26, 2013 ... threshold density values useful for the detection of ovalbumin in samples from ancient works of art. .... slides a mixture of a water solution of dry egg white and the .... ily, facing the problems of sample leakage, background.

  13. Dynamics of hydration in hen egg white lysozyme.

    Science.gov (United States)

    Sterpone, F; Ceccarelli, M; Marchi, M

    2001-08-10

    We investigate the hydration dynamics of a small globular protein, hen egg-white lysozyme. Extensive simulations (two trajectories of 9 ns each) were carried out to identify the time-scales and mechanism of water attachment to this protein. The location of the surface and integral water molecules in lysozyme was also investigated. Three peculiar temporal scales of the hydration dynamics can be discerned: two among these, with sub-nanosecond mean residence time, tau(w), are characteristic of surface hydration water; the slower time-scale (tau(w) approximately 2/3 ns) is associated with buried water molecules in hydrophilic pores and in superficial clefts. The computed tau(w) values in the two independent runs fall in a similar range and are consistent with each other, thus adding extra weight to our result. The tau(w) of surface water obtained from the two independent trajectories is 20 and 24 ps. In both simulations only three water molecules are bound to lysozyme for the entire length of the trajectories, in agreement with nuclear magnetic relaxation dispersion estimates. Locations other than those identified in the protein crystal are found to be possible for these long-residing water molecules. The dynamics of the hydration water molecules observed in our simulations implies that each water molecule visits a multitude of residues during the lifetime of its bound with the protein. The number of residues seen by a single water molecule increases with the time-scale of its residence time and, on average, is equal to one only for the water molecules with shorter residence time. Thus, tau(w) values obtained from inelastic neutron scattering and based on jump-diffusion models are likely not to account for the contribution of water molecules with longer residence time. Copyright 2001 Academic Press.

  14. Preparation of Egg White Liquid Hydrolysate (ELH) and Its Radical-Scavenging Activity

    Science.gov (United States)

    Noh, Dong Ouk; Suh, Hyung Joo

    2015-01-01

    In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of α-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of α-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and α-amino nitrogen content after 24 h-hydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products. PMID:26451355

  15. Microwave-radiation-induced molecular structural rearrangement of hen egg-white lysozyme

    Science.gov (United States)

    Singh, Anang K.; Burada, P. S.; Bhattacharya, Susmita; Bag, Sudipta; Bhattacharya, Amitabha; Dasgupta, Swagata; Roy, Anushree

    2018-05-01

    We have investigated the nonthermal effect of 10 GHz/22 dBm microwave radiation on hen egg-white lysozyme (HEWL) over different irradiation times, ranging from 2 min to 1 h. To ensure a control over the radiation parameters, a pair of microwave rectangular waveguides is used to irradiate the samples. Optical spectroscopic measurements, which include UV-visible absorption spectroscopy, Raman spectroscopy, and far UV CD spectroscopy, reveal the exposure of the buried tryptophan (Trp) residues of the native molecule between 15 and 30 min of radiation. The higher duration of the perturbation leads to a compact structure of the protein and Trp residues are buried again. Interestingly, we do not find any change in the secondary structure of the protein even for 1 h duration of radiation. The relaxation dynamics of the irradiated molecules also has been discussed. We have shown that the molecules relax to their native configuration in 7-8 h after the radiation field is turned off. The structural rearrangement over the above timescale has further been probed by a model calculation, based on a modified Langevin equation. Our coarse-grained simulation approach utilizes the mean of atomic positions and net atomic charge of each amino acid of native HEWL to mimic the initial conformation of the molecule. The modified positions of the residues are then calculated for the given force fields. The simulation results reveal the nonmonotonous change in overall size of the molecule, as observed experimentally. The radiation parameters used in our experiments are very similar to those of some of the electronic devices we often come across. Thus, we believe that the results of our studies on a simple protein structure may help us in understanding the effect of radiation on complex biological systems as well.

  16. The laboratory of irradiated solids

    International Nuclear Information System (INIS)

    1988-01-01

    After a brief recall of results obtained these last twenty years researches in progress are described. Are studied: Solid state physics, particle-matter interactions, crystal defects, nuclear materials. A list of main projects is given [fr

  17. The 1989 progress report: Irradiated solids

    International Nuclear Information System (INIS)

    Novion, C. de.

    1989-01-01

    The 1989 activity report of the laboratory of Irradiated Solids of the Polytechnic School (France) is presented. Investigations on disordered solids are the main field of research. Disorder and its consequences on the physical properties of materials are studied. Some of the most important results are: the experimental demonstration of the creation of defects by electron excitation in iron; the precipitation induced by the irradiation of high temperature electrons; the demonstration of an additional trapping of magnetic flux lines and the increase of the critical current in the YBa2Cu307 superconducting oxyde [fr

  18. Synthesis of ultrafine alumina powders using egg white as complexing medium

    International Nuclear Information System (INIS)

    Salem, R.E.P.; Guilherme, K. A.; Chinelatto, A.S.A.; Chinelatto, A.L.

    2011-01-01

    Synthesis of alumina powders through chemical methods has been attracting much attention of researchers in the past few years, due to the ability to produce powders in nanometric scale with high degree of purity. In this work, there were synthesized alumina powders through a chemical route, using egg white as a complexing medium and aluminium nitrate as the source of Al 3+ cations. Egg white contains ovalbumin, a protein which acts effectively on the isolation of aluminium cations during the mixing process, enabling the formation of ultrafine alumina powders in a relatively economic and environmentally friendly way. The powders obtained by calcinations of the precursor resin were characterized by X-ray diffraction, specific surface area measurements, infrared spectroscopy and scanning electron microscopy. It was observed that the egg white, present at the reaction medium, allowed obtaining transition alumina powders, with high degree of purity. (author)

  19. Continuum emission from irradiated solid deuterium

    DEFF Research Database (Denmark)

    Forrest, J.A.; Brooks, R.L.; Hunt, J.L.

    1992-01-01

    A new emission feature from the spectrum of irradiated solid deuterium has been observed in the very near-infrared spectral region. Experiments from three laboratories, using different excitation conditions, have confirmed the observation. Comparison of the timing and temperature dependence...... of the spectral feature to the information previously available from electron spin resonance studies of solid deuterium, points to atomic association as the underlying cause. We shall show the connection of this emission to the occurrence of thermal spikes and optical flashes, previously observed in solid...

  20. Using modified soy protein to enhance foaming of egg white protein.

    Science.gov (United States)

    Wang, Guang; Troendle, Molly; Reitmeier, Cheryll A; Wang, Tong

    2012-08-15

    It is well known that the foaming properties of egg white protein are significantly reduced when a small amount of yolk is mixed in the white. To improve foaming properties of yolk-contaminated egg white protein, soy protein isolate (SPI) and egg proteins were modified to make basic proteins, and effects of these modified proteins on egg white foaming were evaluated in a model and an angel cake system. SPI and egg yolk proteins were modified to have an isoelectric point of 10, and sonication was used to increase protein dispersibility after the ethyl esterification reaction. However, only the addition of sonicated and modified SPI (SMSPI) showed improvement of foaming in the 5% egg protein model system with 0.4% yolk addition. SMSPI was then used in making angel food cake to examine whether the cake performance reduction due to yolk contamination of the white would be restored by such alkaline protein. Cake performance was improved when cream of tartar was used together with SMSPI. Basic soy protein can be made and used to improve egg white foaming properties and cake performance. Copyright © 2012 Society of Chemical Industry.

  1. Magnetic cation exchange isolation of lysozyme from native hen egg white

    Czech Academy of Sciences Publication Activity Database

    Šafařík, Ivo; Maděrová, Zdeňka; Tokar, O.; Šafaříková, Miroslava

    2007-01-01

    Roč. 45, - (2007), s. 355-359 ISSN 1330-9862 R&D Projects: GA MŠk(CZ) 1P05OC053 Institutional research plan: CEZ:AV0Z60870520 Keywords : magnetic separation * lysozyme * hen egg white Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.906, year: 2007

  2. Differential abundance of egg white proteins in laying hens treated with corticosterone.

    Science.gov (United States)

    Kim, Jimin; Choi, Yang-Ho

    2014-12-24

    Stressful environments can affect not only egg production and quality but also gene and protein abundance in the ovary and oviduct in laying hens. The oviductal magnum of laying hens is the organ responsible for the synthesis and secretion of egg white proteins. The objective of this study was to investigate the effects of dietary corticosterone as a stress model on the abundance of proteins in the egg white and of mRNA and proteins in the magnum in laying hens. After a 14-day acclimation, 40 laying hens were divided into two groups which were provided for the next 14 days with either control (Control) or corticosterone (Stress) diet containing at 30 mg/kg. Corticosterone treatment resulted in increased feed intake (P ≤ 0.05) and decreased egg production. Two-dimensional electrophoresis (2DE) with MALDI-TOF/TOF MS/MS using eggs obtained on days 0 and 5 revealed differential abundance of egg white proteins by Stress: transiently expressed in neural precursors (TENP), hemopexin (HPX), IgY-Fcυ3-4, and extracellular fatty acid-binding protein (Ex-FABP) were decreased while ovoinhibitor and ovalbumin-related protein X (OVAX) were increased on days 5 vs 0 (P ≤ 0.05). Expression of mRNAs and proteins was also significantly modulated in the magnum of hens in Stress on day 14 (P ≤ 0.05). In conclusion, the current study provides the first evidence showing that dietary corticosterone modulates protein abundance in the egg white in laying hens, and it suggests that environmental stress can differentially modify expression of egg white proteins in laying hens.

  3. Genetic control of the humoral immune response to avian egg white lysozymes in the chicken

    International Nuclear Information System (INIS)

    Flanagan, M.P.

    1987-01-01

    Chickens from two closely related sublines, GHs-B6 and GHs-B13, differing serologically at the major histocompatibility complex, were significantly different in their humoral response to three avian egg white lysozymes. Specific antisera levels were measured by radioimmunoassay using 125 I-labeled lysozymes. Antibodies elicited in response to these lysozymes are assumed to be directed against sites on these lysozymes where their amino acid sequence differs from that of the recipient G. domesticus egg white lysozyme (HEL). GHs-B6 birds produced a high level of antibody in response to immunization of turkey (TEL), pheasant (PhL) and guinea hen (GHL) lysozymes. GHs-B13 birds produced no detectable antibody to TEL, were intermediate in their response to PhL and equaled the antibody production of GHs-B6 birds in response to GHL. Antisera to each lysozyme were examined for crossreactivity with all other lysozymes by use of a competitive binding assay

  4. Viscosity of egg white from hens of different strains fed with commercial and natural additives

    Directory of Open Access Journals (Sweden)

    Fernanda Papa Spada

    2012-03-01

    Full Text Available Yolk color and egg white (albumen cleanliness and viscosity are important parameters by which consumers judge the quality of eggs. This study aimed to investigate changes in albumen viscosity during storage of eggs for up to 36 days from two different commercial laying hen strains (Carijo Barbada and Isa Brown fed a diet containing annatto (1.5 and 2.0% or a synthetic additive without synthetic colorants (control. Analyses of humidity, albumen height, pH, viscosity, foam formation, and stability were carried out on eggs. Carijo Barbada strain had smaller albumen, lower humidity and higher egg white viscosity than Isa Brown strain; however, with storage, viscosity lowered significantly on both strains. Initially, the addition of 2.0% of annatto or a synthetic additive increased viscosity in both strains, but with storage only the control maintained longer viscosity. Lower viscosity did not change foam density and stability.

  5. Radiation-induced cross-linking and scissoring of proteins in egg white

    International Nuclear Information System (INIS)

    Josimovic, L.; Radojcic, M.; Milosavljevic, B.H.

    1996-01-01

    Two kinds of radiation-induced protein damages, cross-linking and scissoring, were studied using a thin fraction of avian egg white. It was found that at a dose of 10 kGy in N 2 O saturated samples only one third of the affected protein molecules underwent aggregation, while, contrary to the results obtained with diluted protein solutions, the rest took part in the fragmentation reaction. The fragments obtained had a uniform molecular weight distribution. The overall G-value was found to be 0.25. In air saturated samples the scissoring dominated ten times over cross-linking with the fragments of discrete and well resolved molecular weights. The overall G-value was equal to 0.3. Both G-values are three times smaller than the corresponding values obtained in the experiments with denatured and purified proteins. The egg white radiation stability was found to be, at least in part, due to the presence of glucose which, in turn, acts as an antioxidant. Other relevant factors which may affect the radiation chemistry of the egg white protein composite are also discussed. (author)

  6. Effects on DPPH inhibition of egg-white protein polypeptides treated by pulsed electric field technology.

    Science.gov (United States)

    Wang, Ke; Wang, Jia; Liu, Bolong; Lin, Songyi; Zhao, Ping; Liu, Jingbo; Jones, Gregory; Huang, Hsiang-Chi

    2013-05-01

    Egg-white protein polypeptides are potentially used as a functional ingredient in food products. In this study, the effects on DPPH inhibition of egg-white protein polypeptides ranging from 10 to 30 kDa treated by pulsed electric field (PEF) technology were investigated. 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) inhibition (%) was used to evaluate the antioxidant activity of polypeptides. In order to develop and optimize a pulsed electric field (PEF) mathematical model for improving the antioxidant activity, we have investigated three variables, including concentration (6, 8 and 10 mg mL(-1)), electric field intensity (10, 20 and 30 kV cm(-1)) and pulse frequency (2000, 2350 and 2700 Hz) and subsequently optimized them by response surface methodology (RSM). The concentration (8 mg mL(-1)), electric field intensity (10 kV cm(-1)) and pulse frequency (2000 Hz) were found to be the optimal conditions under which the DPPH inhibition increased 28.44%, compared to the sample without PEF treatment. Both near-infrared spectroscopy (NIR) and mid-infrared spectroscopy (MIR) were used to analyze the change of functional groups. The results showed that PEF technology could improve the antioxidant activity of antioxidant polypeptides from egg-white protein under the optimized conditions. © 2012 Society of Chemical Industry.

  7. Impact of casein and egg white proteins on the structure of wheat gluten-based protein-rich food.

    Science.gov (United States)

    Wouters, Arno G B; Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

    2016-02-01

    There is a growing interest in texturally and nutritionally satisfying vegetable alternatives to meat. Wheat gluten proteins have unique functional properties but a poor nutritional value in comparison to animal proteins. This study investigated the potential of egg white and bovine milk casein with well-balanced amino acid composition to increase the quality of wheat gluten-based protein-rich foods. Heating a wheat gluten (51.4 g)-water (100.0 mL) blend for 120 min at 100 °C increased its firmness less than heating a wheat gluten (33.0 g)-freeze-dried egg white (16.8 g)-water (100.0 mL) blend. In contrast, the addition of casein to the gluten-water blend negatively impacted firmness after heating. Firmness was correlated with loss of protein extractability in sodium dodecyl sulfate containing medium during heating, which was higher with egg white than with casein. Even more, heat-induced polymerization of the gluten-water blend with egg white but not with casein was greater than expected from the losses in extractability of gluten and egg white on their own. Structure formation was favored by mixing gluten with egg white but not with casein. These observations were linked to the intrinsic polymerization behavior of egg white and casein, but also to their interaction with gluten. Thus not all nutritionally suitable proteins can be used for enrichment of gluten-based protein-rich foods. © 2015 Society of Chemical Industry.

  8. Physical properties evaluation of roselle extract-egg white mixture under various drying temperatures

    Science.gov (United States)

    Triyastuti, M. S.; Kumoro, A. C.; Djaeni, M.

    2017-03-01

    Roselle contains anthocyanin that is potential for food colorant. Occasionally, roselle extract is provided in dry powder prepared under high temperature. In this case, the anthocyanin color degrades due to the intervention of heat. The foammat drying with egg white is a potential method to speed up the drying process as well as minimize color degradation. This research aims to study the physical properties of roselle extract under foam mat drying. As indicators, the powder size and color intensity were observed. The result showed that at high temperatures, roselle powder under foam mat drying has the fine size with porous structure. However, at the higher the drying temperature the color retention decreased.

  9. Effects of egg white protein supplementation on muscle strength and serum free amino acid concentrations.

    Science.gov (United States)

    Hida, Azumi; Hasegawa, Yuko; Mekata, Yuko; Usuda, Mika; Masuda, Yasunobu; Kawano, Hitoshi; Kawano, Yukari

    2012-10-19

    The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM), one repetition maximum (1RM) muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal) and carbohydrate group (17.5 g maltodextrin, 78 kcal). Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press) increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength.

  10. Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations

    Directory of Open Access Journals (Sweden)

    Yukari Kawano

    2012-10-01

    Full Text Available The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM, one repetition maximum (1RM muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal and carbohydrate group (17.5 g maltodextrin, 78 kcal. Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength.

  11. Swelling of whey and egg white protein hydrogels with stranded and particulate microstructures.

    Science.gov (United States)

    Li, Hui; Zhao, Lei; Chen, Xiao Dong; Mercadé-Prieto, Ruben

    2016-02-01

    Swelling of protein hydrogels in alkaline conditions strongly depends on the gel microstructure. Stranded transparent gels swell as predicted using a modified Flory-Rehner model with the net protein charge. Particulate opaque gels swell very differently, with a sudden increase at a narrow pH range. Its swelling is not controlled by the protein charge, but by the destruction of the non-covalent interactions. Comparable dissolution thresholds, one with pH and another with the degree of swelling, are observed in both types of microstructures. These conclusions are valid for both whey protein isolate (WPI) gels and egg white gels, suggesting that they are universal for all globular proteins that can form such microscructures. Differences are observed, however, from the prevalent chemical crosslinks in each protein system. Non-covalent interactions dominate WPI gels; when such interactions are destroyed at pH≥11.5 the gels swell extensively and eventually dissolve. In egg white gels, the higher degree of disulphide crosslinking allows extensive swelling when non-covalent interactions are destroyed, but dissolution only occurs at pH≥13 when covalent crosslinks are cleaved. The current study highlights that the microstructure of protein hydrogels, a unique particularity of protein systems compared to other synthetic hydrogels, defines swelling. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations

    Science.gov (United States)

    Hida, Azumi; Hasegawa, Yuko; Mekata, Yuko; Usuda, Mika; Masuda, Yasunobu; Kawano, Hitoshi; Kawano, Yukari

    2012-01-01

    The aim of this study was to evaluate the effects of egg white protein compared to carbohydrate intake prior to exercise on fat free mass (FFM), one repetition maximum (1RM) muscle strength and blood biochemistry in female athletes. Thirty healthy female collegiate athletes were recruited for this study and matched by sport type, body fat percentage and 1RM leg curl muscle strength. Participants were randomly divided into two groups: protein group (15.0 g egg white protein; 75 kcal) and carbohydrate group (17.5 g maltodextrin, 78 kcal). Supplements were administered daily at the same time in a double-blind manner prior to training during an 8-week period. Measurements were performed before and after the 8-week regimen. The mean dietary energy intake did not change throughout the study period. FFM and 1RM assessments (i.e., leg curl, leg extension, squat, and bench press) increased in both groups. Furthermore, serum urea and serum citrulline levels after the 8-week regimen increased significantly only in the protein group. Our findings indicated that compared to the carbohydrate supplement, the protein supplement was associated with some changes in protein metabolites but not with changes in body composition or muscle strength. PMID:23201768

  13. Effect of Guci powder on toe swelling induced by egg white in rats

    Science.gov (United States)

    Xie, Guoqi; Hao, Shaojun; Shen, Huiling; Ma, Zhenzhen; Zhang, Xuehui; Zhang, Zhengchen

    2018-04-01

    To observe the effect of Guci Powder on foot swelling induced by egg white in rats. 50 male rats were randomly divided into normal saline group (n=10), white vinegar group (n=10) and Guning lotion group (n=10). There were 10 rats in the high-dose group and 10 in the low-dose group. The rats in each group were treated with the drug on the left and right feet of the rats. 0.5 hours after the last administration, the rats in each group were inflamed. The left hindsole plantar volume was measured respectively, so that the difference of the posterior toe volume before inflammation was taken as the swelling degree, and the swelling degree of each group was calculated. Compared with physiological saline group, the rats' egg white toe swelling (Pegg white toe in rats was inhibited at 0.5˜2h (Pegg white in rats, and the external application of bone spur powder has anti-inflammatory and swelling effect.

  14. High-pressure protein crystallography of hen egg-white lysozyme

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Hiroyuki; Nagae, Takayuki [Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan); Watanabe, Nobuhisa, E-mail: nobuhisa@nagoya-u.jp [Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan); Nagoya University, Chikusa, Nagoya, Aichi 464-8603 (Japan)

    2015-04-01

    The crystal structure of hen egg-white lysozyme (HEWL) was analyzed under pressures of up to 950 MPa. The high pressure modified the conformation of the molecule and induced a novel phase transition in the tetragonal crystal of HEWL. Crystal structures of hen egg-white lysozyme (HEWL) determined under pressures ranging from ambient pressure to 950 MPa are presented. From 0.1 to 710 MPa, the molecular and internal cavity volumes are monotonically compressed. However, from 710 to 890 MPa the internal cavity volume remains almost constant. Moreover, as the pressure increases to 950 MPa, the tetragonal crystal of HEWL undergoes a phase transition from P4{sub 3}2{sub 1}2 to P4{sub 3}. Under high pressure, the crystal structure of the enzyme undergoes several local and global changes accompanied by changes in hydration structure. For example, water molecules penetrate into an internal cavity neighbouring the active site and induce an alternate conformation of one of the catalytic residues, Glu35. These phenomena have not been detected by conventional X-ray crystal structure analysis and might play an important role in the catalytic activity of HEWL.

  15. Aggregation of egg white proteins with pulsed electric fields and thermal processes.

    Science.gov (United States)

    Wu, Li; Zhao, Wei; Yang, Ruijin; Yan, Wenxu; Sun, Qianyan

    2016-08-01

    Pulsed electric field (PEF) processing is progressing towards application for liquid egg to ensure microbial safety. However, it usually causes protein aggregation, and the mechanism is still unclear. In this study, egg white protein was applied to investigate the changes in protein structure and mechanism of aggregates formation and a comparison was made with thermal treatment. Soluble protein content decreased with the increase of turbidity after both treatments. Fluorescence intensity and free sulfhydryl content were increased after being treated at 70 °C for 4 min. Less-remarkable changes of hydrophobicity were observed after PEF treatments (30 kV cm(-1) , 800 µs). Soluble and insoluble aggregates were observed by thermal treatment, and disulfide bonds were the main binding forces. The main components of insoluble aggregates formed by thermal treatment were ovotransferrin (30.58%), lysozyme (18.47%) and ovalbumin (14.20%). While only insoluble aggregates were detected during PEF processes, which consists of ovotransferrin (11.86%), lysozyme (21.11%) and ovalbumin (31.07%). Electrostatic interaction played a very important role in the aggregates formation. PEF had a minor impact on the structure of egg white protein. PEF had insignificant influence on heat-sensitive protein, indicating that PEF has potential in processing food with high biological activity and heat sensitive properties. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  16. Effects of copper ions on the characteristics of egg white gel induced by strong alkali.

    Science.gov (United States)

    Shao, Yaoyao; Zhao, Yan; Xu, Mingsheng; Chen, Zhangyi; Wang, Shuzhen; Tu, Yonggang

    2017-09-01

    This study investigated the effects of copper ions on egg white (EW) gel induced by strong alkali. Changes in gel characteristics were examined through texture profile analysis, scanning electron microscopy (SEM), and chemical methods. The value of gel strength reached its maximum when 0.1% copper ions was added. However, the lowest cohesiveness values were observed at 0.1%. The springiness of gel without copper ions was significantly greater than the gel with copper ions added. SEM results illustrated that the low concentration of copper ions contributes to a dense and uniform gel network, and an open matrix was formed at 0.4%. The free and total sulphhydryl group content in the egg white protein gel significantly decreased with the increased copper. The increase of copper ions left the contents of ionic and hydrogen bonds basically unchanged, hydrophobic interaction presented an increasing trend, and the disulfide bond exhibited a completely opposite change. The change of surface hydrophobicity proved that the main binding force of copper induced gel was hydrophobic interaction. However, copper ions had no effect on the protein component of the gels. Generally, a low level of copper ions facilitates protein-protein association, which is involved in the characteristics of gels. Instead, high ionic strength had a negative effect on gels induced by strong alkali. © 2017 Poultry Science Association Inc.

  17. Fabrication of redox-responsive magnetic protein microcapsules from hen egg white by the sonochemical method.

    Science.gov (United States)

    Zhong, Shuangling; Cui, Xuejun; Tian, Fangyuan

    2015-01-01

    Redox-responsive magnetic protein microcapsules with Fe3O4 magnetic nanoparticles (MNPs) encapsulated inside have been obtained using a facile, cost-effective and fast sonochemical method from hen egg white proteins. Such prepared redox-responsive magnetic hen egg white protein microcapsules (MHEWPMCs) could be easily manipulated to do magnetic-guided targeting delivery. The synchronous loading of the hydrophobic dye Coumarin 6 as a model of drug into MHEWPMCs was readily achieved during the fabrication of MHEWPMCs by dissolving them into the oil phase before ultrasonication. TEM images indicated that Fe3O4 MNPs were encapsulated in MHEWPMCs. Confocal laser scanning microscopic images indicated that the dye was distributed evenly in the MHEWPMCs and no leakage of dye from the MHEWPMCs was observed due to the protection of protein shells. The MHEWPMCs are potential candidates as attractive carriers for drug targeting delivery and stimuli-responsive release due to their magnetic and redox responsiveness of the disulfide in the microcapsule shells.

  18. Sandis irradiator for dried sewage solids. Final safety analysis report

    International Nuclear Information System (INIS)

    Morris, M.

    1980-07-01

    Analyses of the hazards associated with the operation of the Sandia irradiator for dried sewage solids, as well as methods and design considerations to minimize these hazards, are presented in accordance with DOE directives

  19. Local pH at the surface of hen egg white lysozyme

    Science.gov (United States)

    Otosu, Takuhiro; Kobayashi, Kaito; Yamaguchi, Shoichi

    2018-02-01

    The microenvironment at the surface of hen-egg-white lysozyme (HEWL) was examined by analyzing the change in pKa of fluorescein isothiocyanate (FITC) upon binding to the N-terminus of HEWL. The result showed that the local pH at the HEWL surface is higher than the bulk pH. Furthermore, the data showed that the difference between the local and bulk pH becomes larger with decreasing pH, suggesting HEWL repels more protons at lower pH. Because the local pH affects the protonation states of functional amino-acids at the protein surface, the results provide the fundamental insight into the microenvironment at the protein surface.

  20. Influence of tragacanth gum in egg white based bioplastics: Thermomechanical and water uptake properties.

    Science.gov (United States)

    López-Castejón, María Luisa; Bengoechea, Carlos; García-Morales, Moisés; Martínez, Inmaculada

    2016-11-05

    This study aims to extend the range of applications of tragacanth gum by studying its incorporation into bioplastics formulation, exploring the influence that different gum contents (0-20wt.%) exert over the thermomechanical and water uptake properties of bioplastics based on egg white albumen protein (EW). The effect of plasticizer nature was also evaluated through the modification of the water/glycerol ratio within the plasticizer fraction (fixed at 40wt.%). The addition of tragacanth gum generally yielded an enhancement of the water uptake capacity, being doubled at the highest content. Conversely, presence of tragacanth gum resulted in a considerable decrease in the bioplastic mechanical properties: both tensile strength and maximum elongation were reduced up to 75% approximately when compared to the gum-free system. Ageing of selected samples was also studied, revealing an important effect of storage time when tragacanth gum is present, possibly due to its hydrophilic character. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Production, crystallization and X-ray characterization of chemically glycosylated hen egg-white lysozyme

    International Nuclear Information System (INIS)

    López-Jaramillo, F. J.; Pérez-Banderas, F.; Hernández-Mateo, F.; Santoyo-González, F.

    2005-01-01

    The feasibility of glycosylation post-purification has been demonstrated by introducing glucose into the model protein lysozyme via a novel reaction that is compatible with biological samples. The crystallization of glycoproteins is one of the challenges to be confronted by the crystallographic community in the frame of what is known as glycobiology. The state of the art for the crystallization of glycoproteins is not promising and removal of the carbohydrate chains is generally suggested since they are flexible and a source of heterogeneity. In this paper, the feasibility of introducing glucose into the model protein hen egg-white lysozyme via a post-purification glycosylation reaction that may turn any protein into a model glycoprotein whose carbohydrate fraction can be manipulated is demonstrated

  2. Effect of Egg White Utilization on the Physico-Chemical and Sensory Attributes of Protein-rich Yoghurt

    Directory of Open Access Journals (Sweden)

    Lilian A Gogo

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE High protein yoghurt was made from whole milk, fortified with egg white (30% v/v and skim milk powder at 12% (w/v. Different yoghurt mixes, with albumin content of 15%, 30% and 45% (v/v, were prepared. The control was made from whole milk, fortified with skim milk powder at 12% (w/v. The blended premixes were pasteurized at 74ºC for 4 seconds, cooled and then inoculated with 3% (w/v Direct Vat Set yoghurt starter culture at 45ºC. After fermentation for 3 hours in a water bath maintained at 46+-1C, product was cooled to 5ºC and then stored for 24 hours. The effect of the fortification on physico-chemical and sensory properties was investigated. Protein content increased to 8.50% at 45% egg white utilization. Susceptibility to wheying was reduced in egg-white fortified samples, without signicant difference in sensory attributes of the test samples compared to the control. Sensory analysis showed that yoghurt fortified with 45% egg white was organoleptically acceptable. The yoghurt was rated as having better sensory appeal as compared to the control.

  3. Microwave-Assisted Synthesis of Red-Light Emitting Au Nanoclusters with the Use of Egg White

    Science.gov (United States)

    Tian, Jinghan; Yan, Lei; Sang, Aohua; Yuan, Hongyan; Zheng, Baozhan; Xiao, Dan

    2014-01-01

    We developed a simple, cost-effective, and eco-friendly method to synthesize gold nanoclusters (AuNCs) with red fluorescence. The experiment was performed using HAuCl[subscript 4], egg white, Na[subscript 2]CO[subscript 3] (known as soda ash or washing soda), and a microwave oven. In our experiment, fluorescent AuNCs were prepared within a…

  4. Re-refinement of 4xan: hen egg-white lysozyme with carboplatin in sodium bromide solution

    NARCIS (Netherlands)

    Tanley, Simon W. M.; Schreurs, Antoine M. M.; Kroon - Batenburg, Louise; Helliwell, John R.

    2016-01-01

    A re-refinement of 4xan, hen egg white lysozyme (HEWL) with carboplatin crystallised in NaBr solution, has been made (Tanley et al 2016). This follows our Response article (Tanley et al 2015) to the Critique article of Shabalin et al 2015, suggesting the need for corrections to some solute molecule

  5. Production behavior of irradiation defects in solid breeder materials

    Energy Technology Data Exchange (ETDEWEB)

    Moriyama, Hirotake; Moritani, Kimikazu [Kyoto Univ. (Japan)

    1998-03-01

    The irradiation effects in solid breeder materials are important for the performance assessment of fusion reactor blanket systems. For a clearer understanding of such effects, we have studied the production behavior of irradiation defects in some lithium ceramics by an in-situ luminescence measurement technique under ion beam irradiation. The luminescence spectra were measured at different temperatures, and the temperature-transient behaviors of luminescence intensity were also measured. The production mechanisms of irradiation defects were discussed on the basis of the observations. (author)

  6. Neutron Dosimetry and Irradiation of Solids; Dosimetrie des neutrons et irradiation des solides

    Energy Technology Data Exchange (ETDEWEB)

    Perriot, G; Schmitt, A P [Commissariat a l' Energie Atomique. Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1962-07-01

    Results of work at C.E.A. from 1958 to 1960 are reviewed. The possibilities offered by classical dosimetry methods are discussed. The tests which led to the utilization, for fast neutron dosimetry, of resistivity variations induced in solid W by such neutrons are described. Experimental W irradiation results led to a definition of neutron efficiency which describes the relations between neutron energy and their effects on materials. Possibilities offered by detectors which make use of radiation damage and are sensitive to neutrons at keV energies were explored. In other work, the principal French reactors were classified according to their ability to produce damage in materials such as W. (authors) [French] Dans ce rapport on a presente les resultats essentiels de travaux qui ont ete effectues de 1958 a 1980 par des chercheurs du CEA issus de differents services. En meme temps qu'une revue des possibilites offertes a l'epoque par les methodes classiques de dosimetrie (utilisation des detecteurs par activation), on a decrit les essais qui devaient permettre d'utiliser, a la dosimetrie les neutrons rapides, les variations de resistivite qu'ils creent dans un corps solide (tungstene). L'irradiation du tungstene a montre l'importance qu'il y avait a definir 'l'efficacite' des neutrons, c'est-a-dire leur aptitude plus ou moins grande, selon leur energie, a creer des defauts dans les materiaux. L'efficacite d'un emplacement d'irradiation se trouvant liee au spectre neutronique, on a vu les difficultes qu'il y avait a utiliser les detecteurs par activation des qu'on n'avait plus affaire a un spectre en 1/E ou de fission et on a pu entrevoir les possibilites offertes par les detecteurs utilisant la creation des defauts qui repondent a tous les neutrons d'energies, superieures a quelques keV. Enfin, on a classe les principaux types de Piles Francaises selon leur aptitude a creer plus ou moins rapidement des dommages dans des materiaux comme le tungstene. (auteur)

  7. Experimental and theoretical study of solid solution stability under irradiation

    International Nuclear Information System (INIS)

    Cauvin, Richard.

    1981-08-01

    The behavior of dilute alloys (Al-Zn, Al-Ag, Al-Si, Al-Ge and Al-Mg) under 1 MeV electron irradiation has been studied in a high voltage electron microscope. A phenomenon of homogeneous precipitation induced by irradiation in undersaturated solid solutions (Al-Zn, Al-Ag and Al-Si) has been discovered; the observed precipitates are either coherent or incoherent, but never associated with point defect sinks. The solubility limit is a function of irradiation temperature and flux; but, under irradiation, it does not behave as a true thermal solubility limit (without irradiation). The existing theories (kinetic or strictly thermodynamic) do not account for this phenomenon. It is shown that the irreversibility of the mutual recombination between trapped vacancies and mixed interstitials is the driving force of this homogeneous precipitation. Using a dilute solid solution model, we show that, under irradiation, the homogeneous stationary state, stable from a strictly thermodynamic point of view, can be unstable when the recombination reaction is taken into account. The solubility limit under irradiation is calculated with a nucleation-growth model taking account for this effect; it is proportional to the thermal solubility limit without irradiation. This model explains all the experimental observations [fr

  8. Problems of the heat transfer during the irradiation of solids

    International Nuclear Information System (INIS)

    Jahn, G.

    1981-03-01

    This report deals with the thermal problems during the irradiation of solids. Analytical and constructive solutions are outlined by some examples. Two cases are looked at: 1) the samples and the equipment are warmed up during irradiation. Thus they have to be cooled which yields a negative heat flux direction. 2) The samples shall have a suitable temperature higher than room temperature. Thus they have to be heated which yields a positive heat flux direction. (BHO)

  9. Heating Has No Effect on the Net Protein Utilisation from Egg Whites in Rats

    Directory of Open Access Journals (Sweden)

    Ryosuke Matsuoka

    2017-01-01

    Full Text Available Egg whites (EW are a good source of protein; however, they are typically heated prior to consumption. Therefore, we investigated the effects of different heating conditions on the protein utilisation rate of EW. Male Sprague-Dawley rats (n=36, 198±1 g were divided into six groups and fed American Institute of Nutrition-76 chow containing unheated EW, soft-boiled EW, boiled EW, milk whey protein, soybean protein, or no protein over a 10-day period using pair-feeding. Urine and faeces were sampled daily beginning on day 5 to measure nitrogen content and the net protein utilisation (NPU rate. The soybean protein group had a significantly lower level of food intake and was thus excluded from subsequent analyses. The NPU value was similar among the unheated, soft-boiled, and boiled EW groups (97.5±0.4, 96.5±0.1, and 96.5±0.7, resp.. The EW group values were significantly higher than the whey group values (90.5±1.0. These results show that EW serve as a good source of protein, irrespective of heating.

  10. Food-cooking processes modulate allergenic properties of hen's egg white proteins.

    Science.gov (United States)

    Liu, Xiaoyu; Feng, Bai-Sui; Kong, Xiaoli; Xu, Hong; Li, Xiumin; Yang, Ping-Chang; Liu, Zhigang

    2013-01-01

    Reducing the allergenicity of food allergens can suppress the clinical symptoms of food allergy. The objective of the present study was to investigate the effects of processing on the allergenic properties of hen's egg white proteins. Eggs were processed by traditional Chinese cooking, including steaming, water boiling, frying, spicing and tea boiling. The contents of processed egg protein were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis; the allergenicity was evaluated by Western blotting, enzyme-linked immunosorbent assay and enzyme allergosorbent test inhibition. Circular dichroism spectrum analysis of four major egg allergens from various egg products was performed as well. A mouse model of food allergy was developed to test the allergenicity of processed egg protein in vivo. Protein degradation was significant following tea boiling and spiced-tea boiling. The total allergenic potential of water-boiled egg and fried egg was relatively higher than that of steamed egg, spiced egg and tea-boiled egg. Challenge with proteins from raw egg, water-boiled egg and fried egg induced skewed T-helper 2 pattern responses (Th2 responses) in the intestine of mice sensitized to egg proteins; however, when the mice sensitized to egg proteins were challenged with proteins from steamed egg, spiced egg and tea-boiled egg, respectively, only weak Th2 responses were induced in their intestine. Processing by steaming, spicing, or tea boiling can weaken the allergenicity of egg proteins. Copyright © 2012 S. Karger AG, Basel.

  11. A natural and readily available crowding agent: NMR studies of proteins in hen egg white.

    Science.gov (United States)

    Martorell, Gabriel; Adrover, Miquel; Kelly, Geoff; Temussi, Piero Andrea; Pastore, Annalisa

    2011-05-01

    In vitro studies of biological macromolecules are usually performed in dilute, buffered solutions containing one or just a few different biological macromolecules. Under these conditions, the interactions among molecules are diffusion limited. On the contrary, in living systems, macromolecules of a given type are surrounded by many others, at very high total concentrations. In the last few years, there has been an increasing effort to study biological macromolecules directly in natural crowded environments, as in intact bacterial cells or by mimicking natural crowding by adding proteins, polysaccharides, or even synthetic polymers. Here, we propose the use of hen egg white (HEW) as a simple natural medium, with all features of the media of crowded cells, that could be used by any researcher without difficulty and inexpensively. We present a study of the stability and dynamics behavior of model proteins in HEW, chosen as a prototypical, readily accessible natural medium that can mimic cytosol. We show that two typical globular proteins, dissolved in HEW, give NMR spectra very similar to those obtained in dilute buffers, although dynamic parameters are clearly affected by the crowded medium. The thermal stability of one of these proteins, measured in a range comprising both heat and cold denaturation, is also similar to that in buffer. Our data open new possibilities to the study of proteins in natural crowded media. Copyright © 2010 Wiley-Liss, Inc.

  12. Preparation and preliminary characterization of crystallizing fluorescent derivatives of chicken egg white lysozyme

    Science.gov (United States)

    Sumida, John P.; Forsythe, Elizabeth L.; Pusey, Marc L.

    2001-11-01

    Fluorescence is one of the most versatile and powerful tools for the study of macromolecules. While most proteins are intrinsically fluorescent, working at crystallization concentrations require the use of covalently prepared derivatives added as tracers. This approach requires derivatives that do not markedly affect the crystal packing. We have prepared fluorescent derivatives of chicken egg white lysozyme with probes bound to one of two different sites on the protein molecule. Lucifer yellow and 5-(2-aminoethyl)aminonapthalene-1-sulfonic acid (EDANS) have been attached to the side chain carboxyl of Asp 101 using a carbodiimide coupling procedure. Asp 101 lies within the active site cleft, and it is believed that the probes are "buried" within that cleft. Lucifer yellow and EDANS probes with iodoacetamide reactive groups have been bound to His 15, located on the "back side" of the molecule relative to the active site. All the derivatives fluoresce in the solution and the crystalline states. Fluorescence characterization has focused on determination of binding effects on the probe quantum yield, lifetime, absorption and emission spectra, and quenching by added solutes. Quenching studies show that, as postulated, the Asp 101-bound probes are partially sheltered from the bulk solution by their location within the active site cleft. Probes bound to His 15 have quenching constants about equal to those for the free probes, indicating that this site is highly exposed to the bulk solution.

  13. Effect of guar gum conjugation on functional, antioxidant and antimicrobial activity of egg white lysozyme.

    Science.gov (United States)

    Hamdani, Afshan Mumtaz; Wani, Idrees Ahmed; Bhat, Naseer Ahmad; Siddiqi, Raushid Ahmad

    2018-02-01

    This study was undertaken to analyze the effect of conjugation of egg-white lysozyme with guar gum. Lysozyme is an antimicrobial polypeptide that can be used for food preservation. Its antibacterial activity is limited to gram positive bacteria. Conjugation with polysaccharides like guar gum may broaden its activity against gram negatives. Conjugate was developed through Maillard reaction. Assays carried out included sugar estimation, SDS-PAGE, GPC, color, FT-IR, DSC, thermal stability, solubility, emulsifying, foaming and antioxidant activity. In addition, antimicrobial activity of the conjugate was determined against two gram positive (Staphyllococcus aureus and Enterococcus) and two gram negative pathogens (E. coli and Salmonella). Results showed higher functional properties of lysozyme-guar gum conjugate. The antioxidant properties increased from 2.02-35.80% (Inhibition of DPPH) and 1.65-4.93AAE/g (reducing power) upon guar gum conjugation. Conjugate significantly inhibited gram negative bacteria and the antibacterial activity also increased significantly against gram positive pathogens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Volume properties and spectroscopy: A terahertz Raman investigation of hen egg white lysozyme

    Science.gov (United States)

    Sassi, Paola; Perticaroli, Stefania; Comez, Lucia; Giugliarelli, Alessandra; Paolantoni, Marco; Fioretto, Daniele; Morresi, Assunta

    2013-12-01

    The low frequency depolarized Raman spectra of 100 mg/ml aqueous solutions of hen egg white lysozyme (HEWL) have been collected in the 25-85 °C range. Short and long exposures to high temperatures have been used to modulate the competition between the thermally induced reversible and irreversible denaturation processes. A peculiar temperature evolution of spectra is evidenced under prolonged exposure of the protein solution at temperatures higher than 65 °C. This result is connected to the self-assembling of polypeptide chains and testifies the sensitivity of the technique to the properties of both protein molecule and its surrounding. Solvent free spectra have been obtained after subtraction of elastic and solvent components and assigned to a genuine vibrational contribution of hydrated HEWL. A straight similarity is observed between the solvent-free THz Raman feature and the vibrational density of states as obtained by molecular dynamics simulations; according to this, we verify the relation between this spectroscopic observable and the effective protein volume, and distinguish the properties of this latter respect to those of the hydration shell in the pre-melting region.

  15. Crystallization and evaluation of hen egg-white lysozyme crystals for protein pH titration in the crystalline state.

    Science.gov (United States)

    Iwai, Wakari; Yagi, Daichi; Ishikawa, Takuya; Ohnishi, Yuki; Tanaka, Ichiro; Niimura, Nobuo

    2008-05-01

    To observe the ionized status of the amino acid residues in proteins at different pH (protein pH titration in the crystalline state) by neutron diffraction, hen egg-white lysozyme was crystallized over a wide pH range (2.5-8.0). Crystallization phase diagrams at pH 2.5, 6.0 and 7.5 were determined. At pH diagram, and at pH > 4.5 the border shifted to the right (higher precipitant concentration). The qualities of these crystals were characterized using the Wilson plot method. The qualities of all crystals at different pH were more or less equivalent (B-factor values within 25-40). It is expected that neutron diffraction analysis of these crystals of different pH provides equivalent data in quality for discussions of protein pH titration in the crystalline state of hen egg-white lysozyme.

  16. Anisotropic dewetting of ion irradiated solid films

    Energy Technology Data Exchange (ETDEWEB)

    Repetto, L., E-mail: luca.repetto@unige.it [Dipartimento di fisica, Università di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Šetina Batič, B. [Inštitut Za Kovinske Materiale in Tehnologije, Lepi pot 11, 1000 Ljubljana (Slovenia); Firpo, G.; Piano, E.; Valbusa, U. [Dipartimento di fisica, Università di Genova, Via Dodecaneso 33, 16146 Genova (Italy)

    2013-11-15

    Experiments of irradiation with 30 keV Ga ions were conducted on ultrathin chromium films on rippled silicon substrates. The evolution of their surface morphology, as detected by real time scanning electron microscopy, shows an apparent differential sputtering yield for regions of positive and negative curvature which is in contrast with the standard theory for curvature depending sputtering yield. In particular, at the end of the irradiation process, chromium wires are left in the valleys of the substrate. This result was explained in terms of local melting caused by the ion impact and of a process of dewetting under the concurring actions of surface tension and Van der Waals forces while ion sputtering is active. The interpretation of the reported experimental results are fully supported by numeric simulations implementing the same continuum model used to explain ion induced spinodal dewetting. This hierarchical self-organization process breaks the symmetry of previously demonstrated ion induced dewetting, making possible to create new structures by using the same fundamental effects.

  17. Dosimetry report for the Sandia irradiator for dried sewage solids

    International Nuclear Information System (INIS)

    Greene, R.T.; McFarland, E.W.; Dickson, H.W.

    1981-06-01

    Gamma dose measurements were made at the Sandia Irradiator for Dried Sewage Solids. Passive plastic, chemical, and thermoluminescent dosimeters were exposed in the facility under conditions designed to simulate typical plant operation. Absolute dose and dose distribution information were obtained in air, water, compost, fruit, and sewage sludge

  18. Crystallization and evaluation of hen egg-white lysozyme crystals for protein pH titration in the crystalline state

    International Nuclear Information System (INIS)

    Iwai, Wakari; Yagi, Daichi; Ishikawa, Takuya; Ohnishi, Yuki; Tanaka, Ichiro; Niimura, Nobuo

    2008-01-01

    Hen egg-white lysozyme was crystallized over a wide pH range (2.5–8.0) and the quality of the crystals was characterized. Crystallization phase diagrams at pH 2.5, 6.0 and 7.5 were determined To observe the ionized status of the amino acid residues in proteins at different pH (protein pH titration in the crystalline state) by neutron diffraction, hen egg-white lysozyme was crystallized over a wide pH range (2.5–8.0). Crystallization phase diagrams at pH 2.5, 6.0 and 7.5 were determined. At pH < 4.5 the border between the metastable region and the nucleation region shifted to the left (lower precipitant concentration) in the phase diagram, and at pH > 4.5 the border shifted to the right (higher precipitant concentration). The qualities of these crystals were characterized using the Wilson plot method. The qualities of all crystals at different pH were more or less equivalent (B-factor values within 25–40). It is expected that neutron diffraction analysis of these crystals of different pH provides equivalent data in quality for discussions of protein pH titration in the crystalline state of hen egg-white lysozyme

  19. Chemical structure, comparison antioxidant capacity and separation antioxidant of hen, duck and quail egg white protein hydrolysate

    Science.gov (United States)

    Fatah, A.; Meihu, M.; Ning, Q.; Setiani, B. E.; Bintoro, V. P.

    2018-01-01

    Amino acid linkages as proteins are nutritional substance which important for diet intake. Purification protein procesing undergo heating procedure process followed by additional of proteolytic enzymes or acid had been resulting in protein hydrolysates. A protein hydrolysate describe as many free amino acids bound together through a complex mixture of peptides. Egg white protein hydrolysates is one of subject interested to study for human health or industry product. The objectives of the research are to determine and identification the antioxidant derived from egg white hydrolysate protein. Identification of chemical structure of albumen and albumen protein hydrolysate was examine using IR Spectrophotometry. While comparison of antioxidant capacity and antioxidant separation egg albumen was also investigate using FTIR method (Fourier Transform Infrared Spectroscopy). Hen, duck and quail albumen egg white and on hydrolisate form were used as research materials. The results were showing that different time and enzyme of hydrolysis were not influence at secondary structure of hydrolysate albumen protein. Phytochemical content such as alcohol and hydroxyl compound which have potential as functional group of antioxidant were detected in all of the samples. Their results of radical scavenging activities samples hydrolyzed by pepsin were respectively 89.40%, 50.25% and 85.13%. Whereas the radical scavenging activities of hydrolysates hydrolyzed by papain were 72.85%, 61% and 76.45% respectively.

  20. Hydrolysis of whey by whole cells of Kluyveromyces bulgaricus immobilized in calcium alginate gels in hen egg white

    Energy Technology Data Exchange (ETDEWEB)

    Decleire, M; Huynh, N van; Motte, J C; Cat, W de

    1985-10-01

    Whey hydrolysis was compared in column reactors containing whole yeast cells immobilized in Ca-alginate or in hen egg white in relation to cell US -galactosidase activity, flow rates, temperature and time. With cells of 1.3 U/mg dry weight (ONPG method) immobilized in Ca-alignate, 80% hydrolysis was obtained at 4 and 20C with, respectively 0.50 and 1.65 bed volume/H; the values were 0.2 and 0.74 with cells entrapped in hen egg white. When the flow rate was expressed as ml/H/g wet yeast, no significant difference was observed between both matrices and 80% hydrolysis was reached with a flow rate 1.7 and 5 according to the temperature. The best performance was achieved by the yeast egg white reactor. At 4C, hydrolysis deccreased by 10% after 13 days; by 20% after 17 days. The presence of lactose transport inhibitors in whey did not significantly influence lactose hydrolysis. (orig.).

  1. The efficacy of two electrodes radiofrequency technique: comparison study using a cadaveric interspinous ligament and temperature measurement using egg white.

    Science.gov (United States)

    Lee, Chang-Hyung; Derby, Richard; Choi, Hyun-Seok; Lee, Sang-Heon; Kim, Se Hoon; Kang, Yoon Kyu

    2010-01-01

    One technique in radiofrequency neurotomies uses 2 electrodes that are simultaneously placed to lie parallel to one another. Comparing lesions on cadaveric interspinous ligament tissue and measuring the temperature change in egg white allows us to accurately measure quantitatively the area of the lesion. Fresh cadaver spinal tissue and egg white tissue were used. A series of samples were prepared with the electrodes placed 1 to 7 mm apart. Using radiofrequency, the needle electrodes were heated in sequential or simultaneous order and the distance of the escaped lesion area and temperature were measured. Samples of cadaver interspinous ligament showed sequential heating of the needles limits the placement of the needle electrodes up to 2 mm apart from each other and up to 4 mm apart when heated simultaneously. The temperature at the escaped lesion area decreased according to the distance for egg white. There was a significant difference in temperature at the escaped lesion area up to 6 mm apart and the temperature was above 50 degrees celsius up to 5 mm in simultaneous lesion and 3 mm in the sequential lesion. The limitations of this study include cadaveric experimentation and use of intraspinous ligament rather than medial branch of the dorsal ramus which is difficult to identify. Heating the 2 electrodes simultaneously appears to coagulate a wider area and potentially produce better results in less time.

  2. Dried, irradiated sewage solids as supplemental feed for cattle

    International Nuclear Information System (INIS)

    Smith, G.S.; Kiesling, H.E.; Ray, E.E.; Orcasberro, R.; Trujillo, P.; Herbel, C.H.; Sivinski, J.S.

    1980-01-01

    Sewage solids were collected as 'primary settled solids' and then dried and gamma-irradiated (using 60 Co or 177 Cs) to absorbed dosage of about one magarad to minimize viable parasites and pathogenic organisms. Nutrient composition and bioassays suggested prospective usage as supplemental feed for ruminants. In a large-scale experiment, beef cows grazing poor-quality rangeland forage during late gestation-early lactation were given either no supplemental feed or cottonseed meal or experimental supplement comprised of 62% sewage solids. Supplements were provided for 13 weeks until rangeland forage quality improved seasonably. Supplemental cottenseed meal for cows improved weaning weights of calves by about 11% over unsupplemented controls; whereas, supplement with 62% sewage solids improved calf weaning weights by about 7%. Hazards or risks to animals or to human health appear to be slight when sewage solids of this type are fed as supplemental feeds to cattle in production programs of this type. (Auth.)

  3. Clearing of suspensions of Micrococcus lysodeikticus catalysed by lysozymes from hen, goose, and turkey egg whites, human milk, and phage T4. Assessment of potential as signal generators for homogeneous enzyme immunoassays for urinary steroids.

    Science.gov (United States)

    Cooke, Delwyn G; Blackwell, Leonard F

    2007-01-01

    Lysozymes (3.2.1.17) from goose (Anser anser) egg white, turkey (Melagris gallopavo) egg white, phage T4 and human milk were compared with hen egg white lysozyme in their ability to clear a suspension of Micrococcus lysodeikticus. All of the lysozymes, except hen egg white lysozyme, catalysed the clearing of the Micrococcus lysodeikticus suspension in a biphasic fashion. Compared to hen egg white lysozyme, the total absorbance or transmission change over 5 and 20 minutes was less in all cases, except for human lysozyme. Human lysozyme was, therefore, a potential alternative, more rapid signal generator for the measurement of urinary estrone glucuronide excretion rates because of its structural similarity to hen egg white lysozyme. The apparent K(M) values for hen egg white lysozyme increased with the enzyme concentration.

  4. Evaluation of egg white ovomucin-based porous scaffold as an implantable biomaterial for tissue engineering.

    Science.gov (United States)

    Carpena, Nathaniel T; Abueva, Celine D G; Padalhin, Andrew R; Lee, Byong-Taek

    2017-10-01

    Studies have shown the technological and functional properties of ovomucin (OVN) in the food-agricultural industry. But research has yet to explore its potential as an implantable biomaterial for tissue engineering and regenerative medicine. In this study we isolated OVN from egg white by isoelectric precipitation and fabricated scaffolds with tunable porosity by utilizing its foaming property. Gelatin a known biocompatible material was introduced to stabilize the foams, wherein different ratios of OVN and gelatin had a significant effect on the degree of porosity, pore size and stability of the formed hydrogels. The porous scaffolds were crosslinked with EDC resulting in stable scaffolds with prolonged degradation. Improved cell proliferation and adhesion of rat bone marrow-derived mesenchymal stem cells were observed for OVN containing scaffolds. Although, scaffolds with 75% OVN showed decrease in cell proliferation for L929 fibroblast type of cells. Further biocompatibility assessment as implant material was determined by subcutaneous implantation in rats of selected scaffold. H&E staining showed reasonable vascularization over time and little evidence of severe fibrosis at the implant site. Persistent polarization of classically activated macrophage was not observed, potentially reducing inflammatory response, and showed increased expression of alternatively activated macrophage cells that is favorable for tissue repair. Analysis of IgE levels in rat serum after implantation indicated minimal and resolvable allergic response to the OVN implants. The results demonstrate OVN as an acceptable implant scaffold that could provide new opportunities as an alternative natural biocompatible and functional biomaterial in various biomedical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2107-2117, 2017. © 2016 Wiley Periodicals, Inc.

  5. Purification of Egg White Lysozyme from Indonesian Kampung Chicken and Ducks

    Directory of Open Access Journals (Sweden)

    Z. Wulandari

    2015-04-01

    Full Text Available Egg white lysozyme (EWL has considerably a wide functional protein exhibiting antibacterial activity mainly against Gram-positive bacteria. The EWL is widely applied in food industry and is considerably safe. Despite its high potency, EWL of Indonesian poultry has never been studied and exploited. This study was aimed to purify EWL from two Indonesian poultry: kampung chicken and Cihateup duck, and compared to egg of commercial laying hens. The eggs in this study were obtained from field laboratory of Faculty of Animal Science, Bogor Agricultural University (IPB and classified in AA quality based on the interior quality. First attempt to purify the EWL was performed by using ethanol precipitation yielding purified EWL which was still contaminated by other proteins, hence designated as partially purified EWL. Final concentrations of partially purified EWL of kampung chicken, commercial laying hens, and Cihateup duck were about 5800, 5400, and 5500 μg/mL, respectively. To confirm whether the use of ethanol in the purification affecting EWL antibacterial activities, the activities were examined against Staphylococcus aureus. It demonstrated that the partially purified EWL exhibited ability to inhibit S. aureus at 6 and 26 h suggesting that the method was feasible as it did not interfere EWL antibacterial activities. Yet, based on SDS-Page, purity was the issue in ethanol precipitation method. Further attempt using ion exchange chromatography at pH 10 successfully purified lysozyme as indicated by a single band corresponding to lysozyme size (~14 kD free from bands of other proteins. Altogether, a single step of ion exchange chromatography is sufficient and promising to isolate EWL from Indonesian poultry for various industrial purposes.

  6. Accelerated shelf-life testing of quality loss for a commercial hydrolysed hen egg white powder.

    Science.gov (United States)

    Rao, Qinchun; Rocca-Smith, Jeancarlo R; Schoenfuss, Tonya C; Labuza, Theodore P

    2012-11-15

    In recent years, due to the specific health benefits associated with bioactive peptides and the reduction of protein allergenicity by enzymatic hydrolysis, the utilisation of protein hydrolysates in functional foods and beverages for both protein supplementation and clinical use has significantly increased. However, few studies have explored the moisture-induced effects on food protein hydrolysates, and the resulting changes in the structure and texture of the food matrix as well as the loss in functional properties of bioactive peptides during storage. The main purpose of this study is to determine the influence of water activity (a(w)) on the storage quality of a commercial spray-dried hydrolysed hen egg white powder (HEW). During storage at 45 °C for two months at different a(w)s (0.05-0.79), the selected physicochemical properties of the HEW samples were analysed. Overall, the effect of a(w) on the colour change of HEW at 45 °C for one month was similar to that of HEW after four months at 23 °C due to the presence of a small amount of glucose in HEW. Several structural changes occurred at a(w)s from 0.43 to 0.79 including agglomeration, stickiness and collapse. Kinetic analysis showed a first-order hyperbolic model fit for the change in the L(∗) value, the total colour difference (ΔE(∗)) and the fluorescence intensity (FI). There was a high correlation between colour change and fluorescence, as expected for the Maillard reaction. The reduction in the remaining free amino groups was about 5% at a(w) 0.50 and 6% at a(w) 0.79 after one month storage. In summary, during storage, the Maillard reaction and/or its resulting products could decrease the nutritional value and the quality of HEW. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Solid malignant neoplasms after childhood irradiation: decrease of the relative risk with time after irradiation

    International Nuclear Information System (INIS)

    Vathaire, F. de; Shamsaldin, A.; Grimaud, E.; Campbell, S.; Guerra, M.; Raquin, M.; Hardiman, C.; Jan, P.; Rumeau, N.; Diallo, I.; Nicolazic, G.; Lamon, A.; Oberlin, O.; Cervens, C. de; Suarez, A.; Meresse, V.; Eschwege, F.; Sancho-Garnier, H.; Chavaudra, J.; Lermerle, J.; Bessa, E.; Bell, J.; Hawkins, M.; Schlienger, J.Y.; Panis, X.; Lagrande, J.L.; Gaboriaud, G.; Zucker, J.M.; Daly-Schveitzer, N.

    1995-01-01

    The pattern of the temporal distribution of solid cancer incidence after irradiation in childhood is not well known, although, its importance in radioprotection is well known. We studied a cohort of 1 055 children from 8 European cancer centres, who received radiotherapy between 1942 and 1985 for a first cancer in childhood. After a mean follow-up of 19 years, 26 children developed a solid second malignant neoplasm (SMN), as compared to 5.6 expected from general population rates. Both the excess relative risk and the excess of absolute risk of solid SMN were higher among children who were younger at time of the irradiation. After reaching a maximum 15 to 20 years after irradiation, the excess relative risk of SMN decreased with time after irradiation, when controlling for age at irradiation and sex. The analysis of the risk of thyroid, brain and breast cancer together, as a function of the dose averaged on these 3 organs lead to similar results. (authors). 16 refs., 8 tabs., 2 figs

  8. The active site of hen egg-white lysozyme: flexibility and chemical bonding

    Energy Technology Data Exchange (ETDEWEB)

    Held, Jeanette, E-mail: jeanette.netzel@uni-bayreuth.de; Smaalen, Sander van [University of Bayreuth, D-95440 Bayreuth (Germany)

    2014-04-01

    Chemical bonding at the active site of lysozyme is analyzed on the basis of a multipole model employing transferable multipole parameters from a database. Large B factors at low temperatures reflect frozen-in disorder, but therefore prevent a meaningful free refinement of multipole parameters. Chemical bonding at the active site of hen egg-white lysozyme (HEWL) is analyzed on the basis of Bader’s quantum theory of atoms in molecules [QTAIM; Bader (1994 ▶), Atoms in Molecules: A Quantum Theory. Oxford University Press] applied to electron-density maps derived from a multipole model. The observation is made that the atomic displacement parameters (ADPs) of HEWL at a temperature of 100 K are larger than ADPs in crystals of small biological molecules at 298 K. This feature shows that the ADPs in the cold crystals of HEWL reflect frozen-in disorder rather than thermal vibrations of the atoms. Directly generalizing the results of multipole studies on small-molecule crystals, the important consequence for electron-density analysis of protein crystals is that multipole parameters cannot be independently varied in a meaningful way in structure refinements. Instead, a multipole model for HEWL has been developed by refinement of atomic coordinates and ADPs against the X-ray diffraction data of Wang and coworkers [Wang et al. (2007), Acta Cryst. D63, 1254–1268], while multipole parameters were fixed to the values for transferable multipole parameters from the ELMAM2 database [Domagala et al. (2012), Acta Cryst. A68, 337–351] . Static and dynamic electron densities based on this multipole model are presented. Analysis of their topological properties according to the QTAIM shows that the covalent bonds possess similar properties to the covalent bonds of small molecules. Hydrogen bonds of intermediate strength are identified for the Glu35 and Asp52 residues, which are considered to be essential parts of the active site of HEWL. Furthermore, a series of weak C

  9. The active site of hen egg-white lysozyme: flexibility and chemical bonding

    International Nuclear Information System (INIS)

    Held, Jeanette; Smaalen, Sander van

    2014-01-01

    Chemical bonding at the active site of lysozyme is analyzed on the basis of a multipole model employing transferable multipole parameters from a database. Large B factors at low temperatures reflect frozen-in disorder, but therefore prevent a meaningful free refinement of multipole parameters. Chemical bonding at the active site of hen egg-white lysozyme (HEWL) is analyzed on the basis of Bader’s quantum theory of atoms in molecules [QTAIM; Bader (1994 ▶), Atoms in Molecules: A Quantum Theory. Oxford University Press] applied to electron-density maps derived from a multipole model. The observation is made that the atomic displacement parameters (ADPs) of HEWL at a temperature of 100 K are larger than ADPs in crystals of small biological molecules at 298 K. This feature shows that the ADPs in the cold crystals of HEWL reflect frozen-in disorder rather than thermal vibrations of the atoms. Directly generalizing the results of multipole studies on small-molecule crystals, the important consequence for electron-density analysis of protein crystals is that multipole parameters cannot be independently varied in a meaningful way in structure refinements. Instead, a multipole model for HEWL has been developed by refinement of atomic coordinates and ADPs against the X-ray diffraction data of Wang and coworkers [Wang et al. (2007), Acta Cryst. D63, 1254–1268], while multipole parameters were fixed to the values for transferable multipole parameters from the ELMAM2 database [Domagala et al. (2012), Acta Cryst. A68, 337–351] . Static and dynamic electron densities based on this multipole model are presented. Analysis of their topological properties according to the QTAIM shows that the covalent bonds possess similar properties to the covalent bonds of small molecules. Hydrogen bonds of intermediate strength are identified for the Glu35 and Asp52 residues, which are considered to be essential parts of the active site of HEWL. Furthermore, a series of weak C

  10. Microbial quality of industrial liquid egg white: assumptions on spoiling issues in egg-based chilled desserts.

    Science.gov (United States)

    Techer, Clarisse; Daoud, Amina; Madec, Marie-Noëlle; Gautier, Michel; Jan, Sophie; Baron, Florence

    2015-02-01

    As a 1st step, this study aimed at investigating the microbial quality of liquid egg white in a French egg processing company. Thirty raw and 33 pasteurized liquid egg white samples were analyzed. Pasteurization was globally found efficient on mesophilic contaminants (1.7 ± 1.6 and 0.8 ± 0.9 log CFU/mL in raw and pasteurized samples, respectively), including for the control of Salmonella. However, Gram-positive enterococci were still detected in the pasteurized samples. As a 2nd step, a representative bacterial collection was built for exploring the spoilage issue in egg-based chilled desserts. Custard cream was chosen as growth medium since this food is widely used for the production of French chilled desserts. All of the 166 isolates of the bacterial collection were shown to be able to grow and to induce spoilage of the custard cream at refrigeration temperature (10 °C). Several spoilage types were highlighted in the custard cream, on the basis of changes regarding pH, consistency, production of holes or gas. As a 3rd step, bacterial enzymatic activities were explored on custard cream-based agar media. The bacterial collection was reduced to 43 isolates, based on further selection regarding the genera and the spoilage types previously highlighted. Albeit to different degrees, all these isolates were able to produce proteases. A large part of these isolates also expressed lipolytic and amylolytic activities. This study emphasizes the need to control egg white contamination and especially with Gram-positive heat-resistant Enterococi, in order to guarantee the shelf life of egg-based chilled desserts. © 2015 Institute of Food Technologists®

  11. Determination of ortho-tyrosine in irradiated protein containing foods by HPLC

    International Nuclear Information System (INIS)

    Mischke, J.; Voehringer, M.; Helle, N.; Boegl K.W.; Schreiber, G.A.

    1993-01-01

    In order to control the processing and trading of irradiated foodstuffs several chemical and physical methods have been developed to identify irradiation induced changes. The three most promising methods are gas chromatorgraphic determination of radiation induced volatiles from the lipid content of foods, thermoluminescence measurements on minerals and e.s.r.-spectroscopic measurements on solids and food contents with a low water amount. There is a lack in detecting the irradiation in foods with a high protein content. It is based on the radiation induced hydroxylation of phenylalanine, forming small amounts of ortho- (and meta-) tyrosine. This method can be useful for foods with a low lipid content such as shrimps and pure egg-white. The results obtained on shrimps and egg-white are promising. All shrimp samples showed a good dose dependence which was similar to results reported by Chuaqui-Offermanns and McDougall obtained on frozen materials (chicken) irradiated at a slightly higher dose rate. There are not enough data about o-tyrosine-contents in different kinds of unirradiated shrimps. Therfore next step will be the analysis of a great number of various samples. With these information and by the use of an internal standard it should be possible to apply the HPLC method for routine analysis. As internal standards α-methyltyrosine or 4-hydroxyphenylglycine could be used. (orig./vhe)

  12. Experimental study of swelling of irradiated solid methane during annealing

    International Nuclear Information System (INIS)

    Shabalin, E.; Fedorov, A.; Kulagin, E.; Kulikov, S.; Melikhov, V.; Shabalin, D.

    2008-01-01

    Solid methane, notwithstanding its poor radiation properties, is still widely in use at pulsed neutron sources. One of the specific problems is radiolytic hydrogen gas pressure on the walls of a methane chamber during annealing of methane. Results of experimental study of this phenomenon under fast neutron irradiation with the help of a specially made low temperature irradiation rig at the IBR-2 pulsed reactor are presented. Peak pressure on the wall of the experimental capsule during heating of a sample irradiated at 23-35 K appeared to have a maximum of 27 bar at the absorbed dose 20 MGy, and then falls down with higher doses. Pressure always reached its peak value within the temperature range 72-79 K. Generally, three phases of methane swelling during heating can be distinguished, each characterized by proper rate and intensity. Results of this study were accounted for in design of the solid methane moderator of the second target station of the ISIS facility (England)

  13. Sewage Solids Irradiator Transportation System (SSITS) cask: preliminary design description

    International Nuclear Information System (INIS)

    Eakes, R.G.; Kempka, S.N.; Lamoreaux, G.H.; Sutherland, S.H.

    1983-02-01

    The preliminary design of the Sewage Solids Irradiator Transportation System (SSITS) Cask is presented in this document. The SSITS cask is to be used for the transport of radioactive cesium chloride and strontium fluoride capsules which are of use in irradiators or as heat sources. The SSITS cask is approximately 1.4 m in diameter, 1.3 m high, weighs roughly 9 t, provides 33 cm of steel shielding, and can dissipate up to 5.2 kW of decay heat. The cask design criteria are identified and a description of the cask design and operation is provided. Detailed analyses of the design were performed to demonstrate licensability of the cask by the Nuclear Regulatory Commission (NRC). Results of the analyses indicate that the preliminary design is in compliance with the pertinent regulatory requirements for licensing of a radioactive material transportation container

  14. Egg white hydrolysate shows insulin mimetic and sensitizing effects in 3T3-F442A pre-adipocytes.

    Directory of Open Access Journals (Sweden)

    Forough Jahandideh

    Full Text Available Insulin resistance and inflammation in adipose tissue is a key mechanism underlying metabolic syndrome, a growing health problem characterized by diabetes, obesity and hypertension. Previous work from our research group has demonstrated the potential of egg white ovotransferrin derived bioactive peptides against hypertension, oxidative stress and inflammation in vitro and in vivo. Egg white hydrolysate (EWH has also shown anti-hypertensive effects in spontaneously hypertensive rats. Given the interplay among hypertension, inflammation, oxidative stress and metabolic syndrome, the objective of the study was to test the EWH on differentiation, insulin signaling and inflammatory responses in 3T3-F442A pre-adipocytes. Our study suggested that EWH could promote adipocyte differentiation as shown by increased lipid accumulation, increased release of adiponectin and upregulation of peroxisome proliferator associated receptor gamma (PPARγ and CCAAT/ enhancer binding protein alpha (C/EBP-α. In addition to enhanced insulin effects on the upregulation of protein kinase B/Akt phosphorylation, EWH treatment increased extracellular signal regulated kinase 1/2 (ERK1/2 phosphorylation to a level similar to that of insulin, indicating insulin sensitizing and mimetic properties of the EWH. EWH further attenuated cytokine induced inflammatory marker; cyclooxygenase -2 (COX-2 by 48.78%, possibly through the AP-1 pathway by down regulating c-Jun phosphorylation in adipocytes. Given the critical role of adipose in the pathogenesis of insulin resistance and metabolic syndrome, EWH may have potential applications in the prevention and management of metabolic syndrome and its complications.

  15. Dried, irradiated sewage solids as supplemental feed for cattle

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.S.; Kiesling, H.E.; Ray, E.E.; Orcasberro, R.; Trujillo, P.; Herbel, C.H.

    1979-01-01

    Sewage solids were collected as primary settled solids and then dried and gamma-irradiated (using /sup 60/Co or /sup 137/Cs) to absorbed dosage of about one megarad to minimize viable parasites and pathogenic organisms. Nutrient composition and bioassays with rumen microbes suggested prospective usage as supplemental feed for ruminants. Short-term experiments with sheep and then with cattle further suggested that usage of nutrients could be beneficial and that accumulation of heavy metals was not excessive. A longer-term feeding trial with cattle fed sewage solids as 20% of diet for 68 days demonstrated that tissue uptake of elements such as Cu, Fe and Pb was measurably increased, but not sufficient to exceed ranges considered normal. Likewise, of 22 refractory organic compounds having toxicological interest, only a few were detectible in adipose tissue and none of these exceeded levels that have been reported in tissues from cattle produced conventionally. In a large-scale experiment, beef cows grazing poor-quality rangeland forage during late gestation-early lactation were given either no spplemental feed or cottonseed meal or experimental supplement comprised of 62% sewage solids. Supplements were provided for 13 weeks until rangeland forage quality improved seasonably. Supplemental cottonseed meal for cows improved weaning weights of calves by about 11% over unsupplemented controls; whereas, supplement with 62% sewage solids improved calf weaning weights by about 7%. Hazards or risks to animals or to human health appear to be slight when sewage solids of this type are fed as supplemental feeds to cattle in production programs of this type.

  16. Elastic wave from fast heavy ion irradiation on solids

    CERN Document Server

    Kambara, T; Kanai, Y; Kojima, T M; Nanai, Y; Yoneda, A; Yamazaki, Y

    2002-01-01

    To study the time-dependent mechanical effects of fast heavy ion irradiations, we have irradiated various solids by a short-bunch beam of 95 MeV/u Ar ions and observed elastic waves generated in the bulk. The irradiated targets were square-shaped plates of poly-crystals of metals (Al and Cu), invar alloy, ceramic (Al sub 2 O sub 3), fused silica (SiO sub 2) and single crystals of KC1 and LiF with a thickness of 10 mm. The beam was incident perpendicular to the surface and all ions were stopped in the target. Two piezo-electric ultrasonic sensors were attached to the surface of the target and detected the elastic waves. The elastic waveforms as well as the time structure and intensity of the beam bunch were recorded for each shot of a beam bunch. The sensor placed opposite to the beam spot recorded a clear waveform of the longitudinal wave across the material, except for the invar and fused silica targets. From its propagation time along with the sound velocity and the thickness of the target, the depth of the...

  17. Nitrogen-enriched carbon sheets derived from egg white by using expanded perlite template and its high-performance supercapacitors

    Science.gov (United States)

    Chen, Jiucun; Liu, Yinqin; Li, Wenjun; Xu, Liqun; Yang, Huan; Li, Chang Ming

    2015-08-01

    Nitrogen-enriched carbon sheets were synthesized using egg white as a unique carbon source and expanded perlite as a novel template. The as-prepared material was further used as an electrode material for supercapacitor applications, demonstrating excellent supercapacitance with a maximum gravimetric specific capacitance of 302 F g-1 at 0.5 A g-1 in a 3-electrode setup for a sample carbonized at 850 °C and activated for 6 h. Moreover, the carbon sheet-based capacitor with 2-symmetric electrodes showed an excellent cycle life (2% loss at 0.1 A g-1 after 10 000 cycles). The excellent performance may be attributed to the combination of the 3D carbon structure and the highly concentrated doped nitrogen component from the natural egg source for superior pseudocapacitance.

  18. Effect of intracrystalline water on micro-Vickers hardness in tetragonal hen egg-white lysozyme single crystals

    International Nuclear Information System (INIS)

    Koizumi, H; Kawamoto, H; Tachibana, M; Kojima, K

    2008-01-01

    Mechanical properties of high quality tetragonal hen egg-white lysozyme single crystals which are one type of protein crystal were investigated by the indentation method. The indentation marks were clearly observed on the crystal surface and no elastic recovery of them occurred. The value of the micro-Vickers hardness in the wet condition was estimated to be about 20 MPa at room temperature. The hardness greatly depended on the amount of intracrystalline water (mobile water) contained in the crystals. The hardness increased with increasing evaporation time to air at room temperature. It reached the maximum at about 260 MPa, which is 13 times as much as that in the wet condition. The origin of such a change in hardness was explained in terms of the dislocation mechanisms in lysozyme single crystals

  19. Effectiveness of cross-flow microfiltration for removal of microorganisms associated with unpasteurized liquid egg white from process plant.

    Science.gov (United States)

    Mukhopadhyay, S; Tomasula, P M; Van Hekken, D; Luchansky, J B; Call, J E; Porto-Fett, A

    2009-08-01

    Thermal preservation is used by the egg industry to ensure the microbiological safety of liquid egg white (LEW); however, it does not eliminate all microorganisms and impairs some of the delicate functional properties of LEW. In this study, a pilot-scale cross-flow microfiltration (MF) process was designed to remove the natural microflora present in commercial LEW, obtained from a local egg-breaking plant, while maintaining the nutritional and functional properties of the LEW. LEW, containing approximately 10(6 +/- 1.7) colony forming units (CFU) per milliliter of total aerobic bacteria, was microfiltered using a ceramic membrane with a nominal pore size of 1.4 microm, at a cross-flow velocity of 6 m/s. To facilitate MF, LEW was screened, homogenized, and then diluted (1 : 2, w/w) with distilled water containing 0.5% sodium chloride. Homogenized LEW was found to have a threefold lower viscosity than unhomogenized LEW. Influence of MF temperature (25 and 40 degrees C) and pH (6 and 9) on permeate flux, transmission of egg white nutrients across the membrane, and microbial removal efficiency were evaluated. The pH had a significantly greater influence on permeate flux than temperature. Permeate flux increased by almost 148% when pH of LEW was adjusted from pH 9 to pH 6 at 40 degrees C. Influence of temperature on permeate flux, at a constant pH, however, was found to be inconclusive. Microbial removal efficiency was at least 5 log(10) CFU/mL. Total protein and SDS-PAGE analysis indicated that this MF process did not alter the protein composition of the permeate, compared to that of the feed LEW, and that the foaming properties of LEW were retained in the postfiltered samples.

  20. Structural, magnetic and electrical characterization of Mg–Ni nano-crystalline ferrites prepared through egg-white precursor

    Energy Technology Data Exchange (ETDEWEB)

    Gabal, M.A., E-mail: mgabalabdonada@yahoo.com [Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Al Angari, Y.M. [Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Zaki, H.M. [Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Physics Department, Faculty of Science, Zagazig University, Zagazig (Egypt)

    2014-08-01

    Soft Ni–Mg nano-crystalline ferrites with the general formula Ni{sub 1−x}Mg{sub x}Fe{sub 2}O{sub 4} (0≤x≤1) were synthesized through egg-white method. The precursor decomposition was followed by thermal analysis techniques. The obtained ferrites were characterized by X-ray diffraction, Fourier transform infrared and transmission electron microscopy measurements. X-ray diffraction showed the cubic spinel structure with crystallite size variation within the range 20–45 nm. The different structural data obtained were discussed in the view of ionic radii of the entire ions and their distribution within the lattice. The appropriate suggested cation distribution was then confirmed through Fourier transform infrared as well as electrical and magnetic properties measurements. Transmission electron microscopy exhibited a nano-crystal aggregation phenomenon. The observed size of the spherical particles agrees well with that obtained by X-ray diffraction. Hysteresis loop measurements revealed dilution in the obtained magnetic parameters by Mg-substitution due to the preferential occupancy of Mg{sup 2+} ions by the octahedral sites. Ac-electrical conductivity as a function of temperature and frequency exhibited a semi-conducting behavior with conductivity decreases by increasing Mg-content. The change in the slope of the curve indicates the changing in the conduction mechanism from electron hopping to polaron mechanism by increasing temperature. The obtained structural, electrical and magnetic properties were explained based on the cation distribution among tetrahedral and octahedral sites. - Highlights: • Ni–Mg nano-crystalline ferrites were synthesized through egg-white method. • An appropriate cation distribution was suggested. • Conductivity revealed a change in conduction mechanism by increasing temperature. • The effect of Mg-substitution on different properties was studied.

  1. Ultrasound Pretreatment as an Useful Tool to Enhance Egg White Protein Hydrolysis: Kinetics, Reaction Model, and Thermodinamics.

    Science.gov (United States)

    Jovanović, Jelena R; Stefanović, Andrea B; Šekuljica, Nataša Ž; Tanasković, Sonja M Jakovetić; Dojčinović, Marina B; Bugarski, Branko M; Knežević-Jugović, Zorica D

    2016-09-28

    The impact of ultrasound waves generated by probe-type sonicator and ultrasound cleaning bath on egg white protein susceptibility to hydrolysis by alcalase compared to both thermal pretreatment and conventional enzymatic hydrolysis was quantitatively investigated. A series of hydrolytic reactions was carried out in a stirred tank reactor at different substrate concentrations, enzyme concentrations, and temperatures using untreated, and pretreated egg white proteins (EWPs). The kinetic model based on substrate inhibition and second-order enzyme deactivation successfully predicts the experimental behavior providing an effective tool for comparison and optimization. The ultrasound pretreatments appear to greatly improve the enzymatic hydrolysis of EWPs under different conditions when compare to other methods. The apparent reaction rate constants for proteolysis (k 2 ) are 0.009, 0.011, 0.053, and 0.045 min -1 for untreated EWPs, and those pretreated with heat, probe-type sonicator, and ultrasound cleaning bath technologies, respectively. The ultrasound pretreatment also decreases hydrolysis activation (E a ) and enzyme deactivation (E d ) energy, enthalpy (ΔH), and entropy (ΔS) of activation and for the probe-type sonication this decrease is 61.7%, 61.6%, 63.6%, and 32.2%, respectively, but ultrasound has little change in Gibbs free energy value in the temperature range of 318 to 338 K. The content of sulfhydryl groups and ζ potential show a significant increase (P < 0.05) for both applied ultrasound pretreatments and the reduction of particle size distribution are achieved, providing some evidence that the ultrasound causes EWP structural changes affecting the proteolysis rate. © 2016 Institute of Food Technologists®

  2. Rheological changes in irradiated chicken eggs

    Science.gov (United States)

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

    1998-06-01

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

  3. Rheological changes in irradiated chicken eggs

    International Nuclear Information System (INIS)

    Ferreira, Lucia F. S.; Del Mastro, Nelida L.

    1998-01-01

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

  4. Effect of Different Heat Treatments on In Vitro Digestion of Egg White Proteins and Identification of Bioactive Peptides in Digested Products.

    Science.gov (United States)

    Wang, Xuefen; Qiu, Ning; Liu, Yaping

    2018-04-01

    Chicken eggs are ingested by people after a series of processes, but to date, only a few studies have explored the nutrient variations caused by different heat treatments. In this work, the impacts of different heat treatments (4, 56, 65, and 100 °C on the in vitro digestibility of egg white proteins were investigated by hydrolysis with pepsin or pepsin + pancreatin to simulate human gastrointestinal digestion, and the digested products were identified using Nano-LC-ESI-MS/MS. Egg white proteins treated at 65 °C had the highest in vitro pepsin digestibility value whereas the pepsin + pancreatin digestibility increased significantly (P cooking temperature was raised. The molecular weight distribution of the digested products indicated that, when compared to pepsin-treated samples, pepsin + pancreatin-treated samples contained more low-molecular-weight peptides (m/z egg white digested products, especially in samples treated at 4 and 100 °C. These findings may facilitate a better understanding of nutritive values of egg white proteins and their digested products under different cooking temperatures, such as antibacterial and antioxidant peptides identified in the digestion samples treated, respectively at 4 and 100 °C. This study also provided information for improving the applications of eggs in the food industry as well as a theoretical basis for egg consumption. © 2018 Institute of Food Technologists®.

  5. Egg white hybrid nanoflower (EW-hNF) with biomimetic polyphenol oxidase reactivity: Synthesis, characterization and potential use in decolorization of synthetic dyes.

    Science.gov (United States)

    Altinkaynak, Cevahir; Kocazorbaz, Ebru; Özdemir, Nalan; Zihnioglu, Figen

    2018-04-01

    In this study, for the first time, we described organic-inorganic hybrid nanoflowers using crude egg white as the organic component and copper (II) ions as the inorganic component under the mild conditions. The synthesized egg white-inorganic hybrid nanoflowers (EW-hNFs) were characterized using SEM, EDX, XRD and FTIR analysis. The biomimetic Polyphenol/Peroxidase like activities of synthesized egg white-inorganic hybrid nanoflowers (EW-hNFs) were determined by using various phenolics with or without H 2 O 2 . Optimum pH and temperature, kinetic parameters, reusability, pH and thermal stability of EW-hNFs were also studied. The most noteworthy aspect of our study is that synthesized EW-hNFs which consist of only egg white proteins, showed polyphenol oxidase activity. Furthermore, potential use of the EW-hNFs in the discoloration of the some synthetic dyes was also evaluated. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Modulation of the adsorption properties at air-water interfaces of complexes of egg white ovalbumin with pectin by the dielectric constant

    NARCIS (Netherlands)

    Kudryashova, E.V.; Jongh, H.H.J.de

    2008-01-01

    The possibility of modulating the mesoscopic properties of food colloidal systems by the dielectric constant is studied by determining the impact of small amounts of ethanol (10%) on the adsorption of egg white ovalbumin onto the air-water interface in the absence and presence of pectin. The

  7. Behavior of solid fission products in irradiated fuel

    International Nuclear Information System (INIS)

    Song, Ung Sup; Jung, Yang Hong; Kim, Hee Moon; Yoo, Byun Gok; Kim, Do Sik; Choo, Yong Sun; Hong, Kwon Pyo

    2004-01-01

    Many fission products are generated by fission events in UO 2 fuel under irradiation in nuclear reactor. Concentration of each fission product is changed by conditions of neutron energy spectrum, fissile material, critical thermal power, irradiation period and cooling time. Volatile materials such as Cs and I, the fission products, degrade nuclear fuel rod by the decrease of thermal conductivity in pellet and the stress corrosion cracking in cladding. Metal fission products (white inclusion) make pellet be swelled and decrease volume of pellet by densification. It seems that metal fission products are filled in the pore in pellet and placed between UO 2 lattices as interstitial. In addition, metal oxide state may change structural lattice volume. Considering behavior of fission products mentioned above, concentration of them is important. Fission products could be classified as bellows; solid solution in matrix : Sr, Zr, Nb, Y, La, Ce, Pr, Nd, Pm, Sm - metal precipitates : Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sb, Te - oxide precipitates : Ba, Zr, Nb, Mo, (Rb, Cs, Te) - volatile and gases : Kr, Xe, Br, I, (Rb, Cs, Te)

  8. Consumption of whole eggs promotes greater stimulation of postexercise muscle protein synthesis than consumption of isonitrogenous amounts of egg whites in young men.

    Science.gov (United States)

    van Vliet, Stephan; Shy, Evan L; Abou Sawan, Sidney; Beals, Joseph W; West, Daniel Wd; Skinner, Sarah K; Ulanov, Alexander V; Li, Zhong; Paluska, Scott A; Parsons, Carl M; Moore, Daniel R; Burd, Nicholas A

    2017-12-01

    Background: Protein in the diet is commonly ingested from whole foods that contain various macro- and micronutrients. However, the effect of consuming protein within its natural whole-food matrix on postprandial protein metabolism remains understudied in humans. Objective: We aimed to compare the whole-body and muscle protein metabolic responses after the consumption of whole eggs with egg whites during exercise recovery in young men. Design: In crossover trials, 10 resistance-trained men [aged 21 ± 1 y; 88 ± 3 kg; body fat: 16% ± 1% (means ± SEMs)] received primed continuous l-[ ring - 2 H 5 ]phenylalanine and l-[1- 13 C]leucine infusions and performed a single bout of resistance exercise. After exercise, participants consumed intrinsically l-[5,5,5- 2 H 3 ]leucine-labeled whole eggs (18 g protein, 17 g fat) or egg whites (18 g protein, 0 g fat). Repeated blood and muscle biopsy samples were collected to assess whole-body leucine kinetics, intramuscular signaling, and myofibrillar protein synthesis. Results: Plasma appearance rates of protein-derived leucine were more rapid after the consumption of egg whites than after whole eggs ( P = 0.01). Total plasma availability of leucine over the 300-min postprandial period was similar ( P = 0.75) between the ingestion of whole eggs (68% ± 1%) and egg whites (66% ± 2%), with no difference in whole-body net leucine balance ( P = 0.27). Both whole-egg and egg white conditions increased the phosphorylation of mammalian target of rapamycin complex 1, ribosomal protein S6 kinase 1, and eukaryotic translation initiation factor 4E-binding protein 1 during postexercise recovery (all P egg ingestion increased the postexercise myofibrillar protein synthetic response to a greater extent than did the ingestion of egg whites ( P = 0.04). Conclusions: We show that the ingestion of whole eggs immediately after resistance exercise resulted in greater stimulation of myofibrillar protein synthesis than did the ingestion of egg whites

  9. Structural changes of organic solids caused by irradiation: raman study at very low temperatures

    International Nuclear Information System (INIS)

    Hase, Hirotomo; Ishioka, Kunie; Miyatake, Yoko.

    1995-01-01

    In this paper we first describe a simple liquid helium cryostat and a device of making and mounting organic solid samples. We then present the Raman spectra for irradiated ethanol crystal that were obtained by using the new cryostat and demonstrate how the Raman method is useful for getting insight into structural changes of organic solids caused by irradiation. (J.P.N.)

  10. Thermal Effects Induced by Laser Irradiation of Solids

    International Nuclear Information System (INIS)

    Galovic, S.

    2004-01-01

    A part of incident energy is absorbed within the irradiated sample when a solid is exposed to the influence of laser radiation, to more general electromagnetic radiation within the wide range of wavelengths (from microwaves, to infrared radiation to X-rays), or to the energy of particle beams (electronic, protonic, or ionic). The absorption process signifies a highly selective excitation of the electronic state of atoms or molecules, followed by thermal and non-thermal de-excitation processes. Non-radiation de-excitation-relaxation processes induce direct sample heating. In addition, a great number of non-thermal processes (e.g., photoluminescence, photochemistry, photovoltage) may also induce heat generation as a secondary process. This method of producing heat is called the photothermal effect.The photothermal effect and subsequent propagation of thermal waves on the surface and in the volume of the solid absorbing the exciting beam may produce the following: variations in the temperature on the surfaces of the sample; deformation and displacement of surfaces; secondary infrared radiation (photothermal radiation); the formation of the gradient of the refractivity index; changes in coefficients of reflection and absorbtion; the generation of sound (photoacoustic generation), etc. These phenomena may be used in the investigation and measurement of various material properties since the profile and magnitude of the generated signal depend upon the nature of material absorbing radiation. A series of non-destructive spectroscopic, microscopic and defectoscopic detecting techniques, called photothermal methods, is developed on the basis of the above-mentioned phenomena.This paper outlines the interaction between the intensity modulated laser beam and solids, and presents a mathematical model of generated thermal sources. Generalized models for a photothermal response of optically excited materials have been obtained, including thermal memory influence on the propagation

  11. Recovery of uranium from an irradiated solid target after removal of molybdenum-99 produced from the irradiated target

    Science.gov (United States)

    Reilly, Sean Douglas; May, Iain; Copping, Roy; Dale, Gregory Edward

    2017-10-17

    A process for minimizing waste and maximizing utilization of uranium involves recovering uranium from an irradiated solid target after separating the medical isotope product, molybdenum-99, produced from the irradiated target. The process includes irradiating a solid target comprising uranium to produce fission products comprising molybdenum-99, and thereafter dissolving the target and conditioning the solution to prepare an aqueous nitric acid solution containing irradiated uranium. The acidic solution is then contacted with a solid sorbent whereby molybdenum-99 remains adsorbed to the sorbent for subsequent recovery. The uranium passes through the sorbent. The concentrations of acid and uranium are then adjusted to concentrations suitable for crystallization of uranyl nitrate hydrates. After inducing the crystallization, the uranyl nitrate hydrates are separated from a supernatant. The process results in the purification of uranyl nitrate hydrates from fission products and other contaminants. The uranium is therefore available for reuse, storage, or disposal.

  12. Evaluation of protease resistance and toxicity of amyloid-like food fibrils from whey, soy, kidney bean, and egg white.

    Science.gov (United States)

    Lassé, Moritz; Ulluwishewa, Dulantha; Healy, Jackie; Thompson, Dion; Miller, Antonia; Roy, Nicole; Chitcholtan, Kenny; Gerrard, Juliet A

    2016-02-01

    The structural properties of amyloid fibrils combined with their highly functional surface chemistry make them an attractive new food ingredient, for example as highly effective gelling agents. However, the toxic role of amyloid fibrils in disease may cause some concern about their food safety because it has not been established unequivocally if consumption of food fibrils poses a health risk to consumers. Here we present a study of amyloid-like fibrils from whey, kidney bean, soy bean, and egg white to partially address this concern. Fibrils showed varied resistance to proteolytic digestion in vitro by either Proteinase K, pepsin or pancreatin. The toxicity of mature fibrils was measured in vitro and compared to native protein, early-stage-fibrillar protein, and sonicated fibrils in two immortalised human cancer cell lines, Caco-2 and Hec-1a. There was no reduction in the viability of either Caco-2 or Hec-1a cells after treatment with a fibril concentration of up to 0.25 mg/mL. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. A novel fluorimetric sensing platform for highly sensitive detection of organophosphorus pesticides by using egg white-encapsulated gold nanoclusters.

    Science.gov (United States)

    Yan, Xu; Li, Hongxia; Hu, Tianyu; Su, Xingguang

    2017-05-15

    Assays for organophosphorus pesticides (OPs) with high sensitivity as well as on-site screening have been urgently required to protect ecosystem and prevent disease. Herein, a novel fluorimetric sensing platform was constructed for quantitative detection of OPs via tyrosinase (TYR) enzyme-controlled quenching of gold nanoclusters (AuNCs). One-step green synthetic approach was developed for the synthesis of AuNCs by using chicken egg white (CEW) as template and stabilizer. Initially, TYR can catalyze the oxidation of dopamine to dopaminechrome, which can efficiently quench the fluorescence intensity of AuNCs at 630nm based on dynamic quenching process. However, with the presence of OPs, the activity of TYR was inhibited, resulting in the fluorescence recovery of AuNCs. This proposed fluorescence platform was demonstrated to enable rapid detection for OPs (paraoxon as model) and to provide excellent sensitivity with a detection limit of 0.1ngmL -1 . Significantly, the fluorescence probe was used to prepare paper-based test strips for visual detection of OPs, which validated the excellent potential for real-time and on-site application. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Formation of crystalline nanoparticles by iron binding to pentapeptide (Asp-His-Thr-Lys-Glu) from egg white hydrolysates.

    Science.gov (United States)

    Sun, Na; Cui, Pengbo; Li, Dongmei; Jin, Ziqi; Zhang, Shuyu; Lin, Songyi

    2017-09-20

    A novel peptide from egg white, Asp-His-Thr-Lys-Glu (DHTKE), contains specific amino acids associated with iron binding. The present study aims to better understand the molecular basis of interactions between the DHTKE peptide and iron ions. The ultraviolet-visible and fluorescence spectra indicate an interaction between the DHTKE peptide and iron ions, which leads to the formation of a DHTKE-iron complex. Notably, Asp, Glu, His, and Lys in the DHTKE peptide play crucial roles in the formation of the DHTKE-iron complex, and the iron-binding site of the DHTKE peptide corresponds primarily to the amide and carboxyl groups. The DHTKE peptide can bind iron ions in a 1 : 2 ratio with a binding constant of 1.312 × 10 5 M -1 . Moreover, the DHTKE-iron complex belongs to thermodynamically stable nanoparticles that are present in the crystalline structure, which might be attributed to peptide folding induced by iron binding. Meanwhile, the DHTKE-iron complex exhibits a relatively high iron-releasing percentage and exerts excellent solubility in the human gastrointestinal tract in vitro. This suggests a potential application of peptides containing Asp, Glu, His, or Lys residues as potential iron supplements.

  15. Effect of Egg White Combined with Chalcanthite on Lipopolysaccharide induced Inflammatory Cytokine Expression in RAW 264.7 cells

    Directory of Open Access Journals (Sweden)

    Choi Eun-A

    2012-03-01

    Full Text Available Historically, mineral compound herbal medicines have long been used in treatments of immune-related diseases in Korea, China and other Asian countries. In this study, we inv-estigated the anti-inflammatory effect of egg white combined with chalcanthite (IS4 on lipopolysaccharide (LPS-stimulated RAW 264.7 cells. RAW 264.7 cells cultured with LPS and various con-centrations of IS4 were analyzed to determine the production of pro-inflammatory cytokines and mediators by using enzyme-linked immune sorbent assays (ELISAs. IS4 concentration inhibited the production of interleukin-1beta (IL-1β, interleukin-6 (IL-6, and granulocyte-macrophage colony-stimulating factor (GM-CSF induced by LPS. IS4 at high concentrations (25 and 50`㎍/ml inhibited, in concentration-dependent manner, the expression of tumor necrosis factor-alpha (TNF–α stimulated by LPS. IS4 has shown an anti-inflammatory effect in RAW 264.7 cells.

  16. Effect of glutinous rice flour and dried egg white in fabrication of porous cordierite by gel casting method

    Directory of Open Access Journals (Sweden)

    A. Kamil Fakhruddin

    Full Text Available Abstract In this study, cordierite was produced using MgO, SiO2 and Al2O3 as raw materials through glass route method. The raw materials were mixed for 6 h and the mixture was melted at 1550 °C and then water quenched. The glass produced was milled for 5 h to obtain fine powder, which was used to prepare porous cordierite through gel casting method. The effect of addition of different natural binders, glutinous rice flour (GRF and dried egg white (DEW, on porous cordierite was investigated. GRF and DEW were added to the slurry during mixing. The synthesized cordierite powder was analyzed by X-ray diffraction. Porous cordierite was characterized through Archimedes method, morphological analysis, and compression test. The porosity level varied from 60.6% to 78.7% depending on the amount of natural binder added. Compression test results showed that the compressive strength of porous cordierite increased with increasing amount of natural binder added.

  17. Modelling with response surface methodology of the effects of egg yolk, egg white and sodium carbonate on some textural properties of beef patties.

    Science.gov (United States)

    Parlak, Ozgür; Zorba, Omer; Kurt, Sükrü

    2014-04-01

    This study was accomplished to determine the effects of egg yolk, egg white and sodium carbonate on textural properties of beef patties by using Central Composite Design of Response Surface Methodology. Meat patties were prepared using beef, lamb tail fat and spices. Effects of addition of egg yolk powder (0-1%), egg white powder (0-1%) and sodium carbonate (0-1%) on textural properties were studied by using a texture analyzer. The TPA and cutting force tests were measured in the samples. Effects of sodium carbonate were found to be significant (P  0.05). The levels of sodium carbonate up to 0.72% improved the textural properties of beef patties.

  18. A solution for the preparation of hexagonal M-type SrFe{sub 12}O{sub 19} ferrite using egg-white: Structural and magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tingting; Li, Yang; Wu, Ruonan; Zhou, Han; Fang, Xiaochen [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China); Su, Shubing [School of Electronic and Information Engineering, Ningbo University of Technology, Ningbo 315016 (China); Xia, Ailin, E-mail: alxia@126.com [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China); Jin, Chuangui; Liu, Xianguo [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002 (China)

    2015-11-01

    A new sol–gel route using egg-white as the binder of metal ions, is developed to prepare hexagonal M-type SrFe{sub 12}O{sub 19} ferrite in this study, and the effects of different atomic ratio of Sr and Fe (Sr/Fe), sintering temperature (T{sub s}) and usage of egg-white (M{sub ew}) on the phase formation, morphology and magnetic properties of specimens are studied. It is found that the single-phase SrFe{sub 12}O{sub 19} ferrite only can be obtained under a Sr/Fe of 1:8 and a T{sub s} between 1000 °C and 1300 °C. The magnetic properties of specimens are also obviously affected by the different Sr/Fe and T{sub s}, primarily due to the emergency of impurities. The M{sub ew} has an obvious impact on the crystallinity of specimens, which consequently affects their magnetic properties. In our study, the optimum conditions to prepare the single-phase SrFe{sub 12}O{sub 19} ferrite are Sr/Fe=1:8, M{sub ew}= 3 g and T{sub s} =1200 °C. - Highlights: • Single-phase SrM ferrite was obtained via a novel sol–gel method using egg-white. • Single-phase SrM ferrite was obtained under Sr/Fe=1:8 and T{sub s} between 1000 and 1300 °C. • The usage of egg-white affects the crystallinity and magnetic properties markedly.

  19. Crystallization and preliminary x-ray structure analysis of the egg-white lysozyme from a Taiwanese Soft-Shelled Turtle (Tri onyx Sinensis Wiegmann)

    International Nuclear Information System (INIS)

    Siritapetawee, Jaruwan; Thammasirirak, Sompong; Yuvaniyama, Jirudon

    2005-10-01

    Lysozyme has been purified from the egg-white of a Taiwanese soft-shelled turtle. This soft-shelled turtle ' s egg-white lysozyme migrated on 12.5% SDS-PAGE at about 14.8 kDa. The lysozyme has been crystallized using the sitting drop vapor diffusion technique and 30% (w/v) polyethylene glycol 8000 in 0.1 M sodium cacodylate, p H 6.5 containing 0.2 M ammonium sulfate as a precipitant. One of the crystals diffracted X rays beyond 2 angstrom unit resolution and belonged to the orthorhombic, space group P212121, with unit cell dimensions of a = 37.8 angstrom unit, b = 55.6 angstrom unit, and c 72.2 angstrom unit and one molecule of the enzyme per asymmetric unit. The data were collected to 1.9 angstrom resolution with an R merge of 4.6%, suitable for high resolution structure analysis. The single-crystal X-ray structure of lysozyme has been initially phased with the Molecular Replacement technique using pheasant egg-white lysozyme (PDB ID 1GHL) as a search template. Model rebuilding and refinement are in progress

  20. Thermal inactivation of H5N2 high-pathogenicity avian influenza virus in dried egg white with 7.5% moisture.

    Science.gov (United States)

    Thomas, Colleen; Swayne, David E

    2009-09-01

    High-pathogenicity avian influenza viruses (HPAIV) cause severe systemic disease with high mortality in chickens. Isolation of HPAIV from the internal contents of chicken eggs has been reported, and this is cause for concern because HPAIV can be spread by movement of poultry products during marketing and trade activity. This study presents thermal inactivation data for the HPAIV strain A/chicken/PA/1370/83 (H5N2) (PA/83) in dried egg white with a moisture content (7.5%) similar to that found in commercially available spray-dried egg white products. The 95% upper confidence limits for D-values calculated from linear regression of the survival curves at 54.4, 60.0, 65.5, and 71.1 degrees C were 475.4, 192.2, 141.0, and 50.1 min, respectively. The line equation y = [0.05494 x degrees C] + 5.5693 (root mean square error = 0.0711) was obtained by linear regression of experimental D-values versus temperature. Conservative predictions based on the thermal inactivation data suggest that standard industry pasteurization protocols would be very effective for HPAIV inactivation in dried egg white. For example, these calculations predict that a 7-log reduction would take only 2.6 days at 54.4 degrees C.

  1. Studies on rate equations for defects in irradiated solids using the local analysis method

    International Nuclear Information System (INIS)

    Carvalho e Camargo, M.U. de.

    1983-10-01

    The void formation and swelling phenomenon in material for nuclear reactors structures, mainly for fast reactors, has been studied by several authors. A simple calculation covering the basic instance of radiation damage in irradiated solid solution, using the local analysis in rate theory is presented here. A simple description of pratical and fundamental interest for the complex problem of solid solution under irradiation is given. (Author) [pt

  2. Foams prepared from whey protein isolate and egg white protein: 2. Changes associated with angel food cake functionality.

    Science.gov (United States)

    Berry, Tristan K; Yang, Xin; Foegeding, E Allen

    2009-06-01

    The effects of sucrose on the physical properties and thermal stability of foams prepared from 10% (w/v) protein solutions of whey protein isolate (WPI), egg white protein (EWP), and their combinations (WPI/EWP) were investigated in wet foams and angel food cakes. Incorporation of 12.8 (w/v) sucrose increased EWP foam stability (drainage 1/2 life) but had little effect on the stability of WPI and WPI/EWP foams. Increased stability was not due to viscosity alone. Sucrose increased interfacial elasticity (E ') of EWP and decreased E' of WPI and WPI/EWP combinations, suggesting that altered interfacial properties increased stability in EWP foams. Although 25% WPI/75% EWP cakes had similar volumes as EWP cakes, cakes containing WPI had larger air cells. Changes during heating showed that EWP foams had network formation starting at 45 degrees C, which was not observed in WPI and WPI/EWP foams. Moreover, in batters, which are foams with additional sugar and flour, a stable foam network was observed from 25 to 85 degrees C for batters made from EWP foams. Batters containing WPI or WPI/EWP mixtures showed signs of destabilization starting at 25 degrees C. These results show that sucrose greatly improved the stability of wet EWP foams and that EWP foams form network structures that remain stable during heating. In contrast, sucrose had minimal effects on stability of WPI and WPI/EWP wet foams, and batters containing these foams showed destabilization prior to heating. Therefore, destabilization processes occurring in the wet foams and during baking account for differences in angel food cake quality.

  3. Binding of naringin and naringenin with hen egg white lysozyme: A spectroscopic investigation and molecular docking study

    Science.gov (United States)

    Das, Sourav; Ghosh, Pooja; Koley, Sudipta; Singha Roy, Atanu

    2018-03-01

    The interactions of naringenin (NG) and naringin (NR) with Hen Egg White Lysozyme (HEWL) in aqueous medium have been investigated using UV-vis spectroscopy, steady-state fluorescence, circular dichroism (CD), Fourier Transform infrared spectroscopy (FT-IR) and molecular docking analyses. Both NG and NR can quench the intrinsic fluorescence of HEWL via static quenching mechanism. At 300 K, the value of binding constant (Kb) of HEWL-NG complex (5.596 ± 0.063 × 104 M- 1) was found to be greater than that of HEWL-NR complex (3.404 ± 0.407 × 104 M- 1). The negative ΔG° values in cases of both the complexes specify the spontaneous binding. The binding distance between the donor (HEWL) and acceptor (NG/NR) was estimated using the Försters theory and the possibility of non-radiative energy transfer from HEWL to NG/NR was observed. The presence of metal ions (Ca2 +, Cu2 + and Fe2 +) decreased the binding affinity of NG/NR towards HEWL. Synchronous fluorescence studies indicate the change in Trp micro-environment due to the incorporation of NG/NR into HEWL. CD and FT-IR studies indicated that the α-helicity of the HEWL was slightly enhanced due to ligand binding. NG and NR inhibited the enzymatic activity of HEWL and exhibited their affinity for the active site of HEWL. Molecular docking studies revealed that both NG and NR bind in the close vicinity of Trp 62 and Trp 63 residues which is vital for the catalytic activity.

  4. Effect of gamma irradiation on cefotaxime in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Zegota, H.; Koprowski, M.; Zegota, A. [Technical Univ., Lodz (Poland). Inst. of Applied Radiation Chemistry

    1995-02-01

    The effect of {gamma}-irradiation on cefotaxime, a member of the third generation of cephalosporins, has been investigated by using different spectroscopic, chromatographic and microbiological analytical methods. Cefotaxime sodium salt was irradiated in dry state in the range of sterilization doses from 5.85 to 46.8 kGy. According to the results obtained, the degree of cefotaxime alterations was lower than 1%, even for the higher radiation dose used. Trace amounts of antibiotic radiolysis products have been found by HPLC. The microbiological assay carried out using E. coli test strain reveal that the activity of irradiated cefotaxime did not decrease. (author).

  5. A low temperature cryostat with a refrigerator for studying electron irradiation effects on solids

    International Nuclear Information System (INIS)

    Oka, Takashi; Yoshida, Toshio; Kitagawa, Michiharu; Yanai, Masayoshi

    1976-01-01

    A low temperature cryostat with a small cryogenic refrigerator is described which is convenient for studying irradiation effects of the energetic electrons on solids. It allows a sample to be kept about 12 K without irradiation and 15 K under the irradiation at a heating rate of 1.5 w. The sample temperature can be changed up to room temperature by adjusting the power of an attached heater and the pressure of a compressor for the refrigerator. The optical and electrical properties of the sample can be measured under and after irradiation. (auth.)

  6. Stability of cefuroxime following gamma-irradiation in the solid state

    International Nuclear Information System (INIS)

    Zegota, Henryk; Koprowski, Marek; Zegota, Alicja

    1994-01-01

    The effect of γ-irradiation on cefuroxime, a member of the second generation of cephalosporins, has been assessed by different spectroscopic, HPLC, chemical and microbiological analytical methods. According to the results obtained, the chemical changes in irradiated cefuroxime have relatively low yield. The microbiological assay carried out using Bacillus subtilis test strain reveal that the activity of irradiated cefuroxime did not decrease even for radiation doses as high as 85 kGy. The remarkable radiation stability of cefuroxime irradiated in the solid state supports its suitability for radiation sterilization. (author)

  7. Stability of cefuroxime following gamma-irradiation in the solid state

    Energy Technology Data Exchange (ETDEWEB)

    Zegota, Henryk; Koprowski, Marek; Zegota, Alicja (Politechnika Lodzka, Lodz (Poland). Katedra Chemii Radiacyjnej)

    1994-04-01

    The effect of [gamma]-irradiation on cefuroxime, a member of the second generation of cephalosporins, has been assessed by different spectroscopic, HPLC, chemical and microbiological analytical methods. According to the results obtained, the chemical changes in irradiated cefuroxime have relatively low yield. The microbiological assay carried out using Bacillus subtilis test strain reveal that the activity of irradiated cefuroxime did not decrease even for radiation doses as high as 85 kGy. The remarkable radiation stability of cefuroxime irradiated in the solid state supports its suitability for radiation sterilization. (author).

  8. Size Exclusion Chromatography Studies of the Initial Self-Association Steps of Chicken Egg White Lysozyme Nucleation

    Science.gov (United States)

    Ewing, Felecia; Donovan, David; Pusey, Marc

    2000-01-01

    Nucleation is one of the least understood aspects of crystallogenesis. In the case of macromolecule nucleation, this understanding is further hampered by uncertainty over what precisely is being discussed. We define the process of solute self-association (aggregation, oligomerization, interaction, clustering, etc.) whereby n-mers (n > or = 2) having a crystallographic or nascent crystallographic arrangement leading to the critical nucleus reversibly form in the solution, to be part of the nucleation process. This reversible self-association process is a fundamental part of the nucleation process, and occurs as a function of the solute concentration. In the case of chicken egg white lysozyme, a considerable body of experimental evidence leads us to the conclusion that it also forms the crystal growth units. Size exclusion chromatography is a simple and direct method for determining the equilibrium constants for the self-association process. A Pharmacia FPLC system was used to provide accurate solution flow rates. The column, injection valve, and sample loop were all mounted within a temperature-controlled chamber. Chromatographically re-purified lysozyme was first dialyzed against the column equilibration buffer, with injection onto the column after several hours pre-incubation at the running temperature. Preliminary experiments, were carried out using a Toyopearl HW-50F column (1 x 50cm), equilibrated with 0.1 M sodium acetate, 5% sodium chloride, pH 4.6, at 15C. Protein concentrations from 0.1 to 4 mg/ml were employed (C(sub sat) = 1.2 mg/ml). The data from several different protein preparations consistently shows a progressively decreasing elution volume with increasing protein concentration, indicating that reversible self-association is occurring. The dotted line indicates the monomeric lysozyme elution volume. However, lysozyme interacts with the column matrix in these experiments, which complicates data analysis.Accordingly, we are testing silica-based HPLC

  9. Assessment of the Inhibitory Effect of Rifampicin on Amyloid Formation of Hen Egg White Lysozyme: Thioflavin T Fluorescence Assay versus FTIR Difference Spectroscopy

    Directory of Open Access Journals (Sweden)

    Gang Ma

    2014-01-01

    Full Text Available The inhibitory effect of rifampicin on the amyloid formation of hen egg white lysozyme was assessed with both Thioflavin T (ThT fluorescence assay and Fourier transform infrared (FTIR difference spectroscopy. We reveal that ThT fluorescence assay gives a false positive result due to rifampicin interference, while FTIR difference spectroscopy provides a reliable assessment. With FTIR, we show that rifampicin only has marginally inhibitory effect. We then propose that FTIR difference spectroscopy can potentially be a convenient method for inhibitor screening in amyloid study.

  10. Measurement and calculation of radiation fields of the Sandia irradiator for dried sewage solids

    International Nuclear Information System (INIS)

    Morris, M.E.

    1981-03-01

    The radiation field of the Sandia Irradiator for Dried Sewage Solids was measured. The results of the measurement are given in this report. In addition, theoretical calculations of the fields are given and then compared with the measured values. Elementary models of the radiation source geometry and irradiated product are found to be adequate and thus allow us to duplicate (through calculation) the important features of the measured fields

  11. Dried gamma-irradiated sewage solids use on calcareous soils: crop yields and heavy metals uptake

    International Nuclear Information System (INIS)

    McCaslin, B.D.; Sivinski, J.S.

    1980-01-01

    The fertilizer values of gamma-irradiated digested sewage solids (RDSS) and gamma-irradiated undigested sewage solids (RUSS) have been examined on calcareous soils. Previously published data from Sandia Laboratories have shown that approximately 1 mega-rad of gamma-irradiation effectively destroys pathogenic bacteria, parasites and plant seeds in dried sewage solids. Greenhouse experiments directly comparing gamma-irradiated and non-irradiated undigested and digested dried sewage solids as fertilizers indicate little or no effect of 1 mega-rad gamma radiation treatment on plant yield or plant-nutrient uptake and demonstrated considerable benefit from using sewage solids on calcareous soils. Plant response to undigested sewage solids was considerably greater than to digested sewage solids when applied at levels that were isonitrogenous. The calcareous soils in New Mexico typically range in pH from 7.5 to 9.0, limiting the plant-availability of many elements, especially heavy metals. Soils irrigated with sewage-effluent for 40 years demonstrated beneficial use of supplied plant-nutrients with no apparent increase in plant-uptake of heavy metals. RDSS applied to a calcareous soil low in plant-available iron increased plant growth in the greenhouse considerably more than treatments with equal amounts of nitrogen, phosphorus and iron applied as common fertilizer materials. Plant tissue concentrations of Fe, Zn, Mn and Cu showed that RDSS was a good source of these nutrients. Results also indicated that the total soluble salt concentration of the RDSS was the factor most limiting plant growth. Chromium, Cd, Ni and Pd plant-tissue concentrations were apparently not increased by RDSS treatments. (Auth.)

  12. Irradiation of solid Walker carcino-sarcomas after synchronisation with hydroxyurea

    International Nuclear Information System (INIS)

    Wayss, K.; Mattern, J.; Volm, M.

    1980-01-01

    Sprague-Dawley rats with solid Walker carcino-sarcomas were synchronized with hydroxyurea (HU; 6 x 50 mg and 1 x 300 mg HU/kg body weight) and then irradiated at different time points ( 60 Co). The synchronized tumors showed a significant delay of growth when irradiation was applied in the late G1 phase, at the transition G1/S and in the early S phase. The remaining phases of the cell cycle, especially the S phase showed the same sensitivity as the non-synchronized controls. Improvement of therapy by irradiation after HU application was largely due to the synchronization of tumor cells. Only the increased therapeutic effect of irradiation shortly after application of HU can be explained also by combination of both HU and irradiation. (orig.) 891 MG/orig. 892 MKO [de

  13. Use of lysozyme from chicken egg white as a nitrite replacer in an Italian-type chicken sausage

    Directory of Open Access Journals (Sweden)

    Nalaka Sandun Abeyrathne

    2015-09-01

    Full Text Available Background: Sodium or potassium nitrite is widely used as a curing agent in sausages and other cured meat products. Nitrite has strong antimicrobial and antioxidant effects and generates cured meat color. Nitrite, however, can react with secondary or tertiary amines in meat to form carcinogenic, teratogenic and mutagenic N-nitroso compounds. Several findings have been suggested that high consumption of processed meat may increase the risk of cancer, and emphasized that dietary nitrosamines are positively associated with cancer. Lysozyme is one of the major egg proteins that have antimicrobial and antioxidant characteristics. Therefore, lysozyme can be used in meat processing to prevent microbial growth and oxidative degradation in meat products during storage. This study is focused on evaluating the antimicrobial and antioxidant effects of lysozyme extracted from egg white as a replacer of nitrite in a cooked Italian-type chicken sausage. Methods: Four curing treatments including 100% nitrite (control, 100% lysozyme (treatment 1, 25% nitrite + 75% lysozyme (treatment 2 and 50% nitrite + 50% lysozyme (treatment 3 were used to prepare Italian-type chicken sausage samples. Recipe was developed with 64% (w/w meat, 17% (w/w binder (bread crumble, 12% (w/w ice, 4% (w/w vegetable oil, 2% (w/w salt, 1% (w/w spices (chili, black pepper, cardamom. Prepared samples were cooked in an 80 °C smoke house to a core temperature of 65 °C and cooled in cold water to 20-25 °C subsequently packed in polyethylene and stored in a freezer (-18 °C. The antimicrobial effect lysozyme was tested using Escherichia coli and Salmonella. The growth of these pathogens at 0, 3 and 5 days of storage of spore inoculation was determined. The antioxidant activity of lysozyme was determined using the TBARS value during the 25 d storage period. The redness (a*, lightness (L*, and yellowness (b* of sausages were analyzed using a Minolta color meter (CR 410, Konica Minolta Inc

  14. Characteristics of Nanosize Spinel NixFe3-xO4 Prepared by Sol-Gel Method Using Egg White as Emulsifying Agent

    Directory of Open Access Journals (Sweden)

    Rudy Situmeang

    2015-07-01

    Full Text Available In this study, sol-gel method using egg white as emulsifying agent was applied to prepare nano size spinel NixFe3-xO4 (with x = 0.2–1. Sample preparation was carried out by mixing the solution of Fe(NO33.9 H2O and Ni(NO33.6 H2O with egg white, and then the sample was stirred thoroughly using magnetic stirrer. After freeze–drying process, the sample was subjected to calcination treatment and subsequently characterized. The phase composition was evaluated using the X-ray diffraction (XRD technique, followed by quantitative analysis using Rietveld and Debye-Scherrer Methods. The functionality of the sample was identified using Fourier Transform Infrared (FTIR spectroscopy, and surface morphology and elemental composition were analyzed using scanning electron microscopycoupled with electron dispersive spectroscopy (SEM/EDS. The results of XRD characterization indicated that materials consist of various crystalline phases, with NiFe2O4 as a major phase. FTIR Analysis revealed the existence of both Lewis and Brønsted–Lowry acid sites, with Lewis acid as the prominent site. The sample was found to display relatively homogeneous surface morphology, having the crystallite size in the range of 33 to 61 nm according to the Debye-Scherrer equation. The EDS data indicated that the ratio of Fe/Ni is in agreement with the composition of the raw materials used.

  15. Preparation by irradiation of a solid support for enzyme immunoassay

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1984-01-01

    Reagents (immobilized anti-α-fetoprotein discs) having a porous structure were prepared for enzyme immunoassay of α-fetoprotein by radiation polymerization at low temperatures. Discs were attached to sticks for easy handling. The activity (determined by absorbance at 492 nm) of the discs varied with the hydrophilic properties and size of the discs. The discs are sufficiently sensitive and precise for enzyme immunoassay of α-fetoprotein. Anti-AFP dissolved in PBS solution was mixed with a monomer solution of hydroxyethyl methacrylate and hydroxypropyl methacrylate. The mixture was frozen to -78 0 C and gamma irradiated. (Auth.)

  16. Effects of irradiation on four solid breeder materials

    International Nuclear Information System (INIS)

    Hollenberg, G.W.

    1984-01-01

    The tritium breeding material with the highest lithium atom density, Li 2 O has been observed to incur significant swelling (>4%) under fast reactor irradiation. Such swelling, if unrestrained leads to either unacceptable, induced-strains in adjacent structural material or undesirable design compromises. Fortunately, however, Li 2 O deforms at low temperatures so that swelling strains may be internally accommodated. Laboratory dilational creep experiments were conducted on unirraciated Li 2 O between 500 and 700 0 C in order to provide data for structural analysis of in-reactor experiments and blanket design studies. A densification model agreed with most of the available data. 15 refs

  17. A low temperature cryostat with a refrigerator for studying electron-irradiation effects on solids, 2

    International Nuclear Information System (INIS)

    Oka, Takashi; Yoshida, Toshio; Shono, Yoshihiko

    1978-01-01

    A convenient cryostat with a small cryogenic refrigerator for studying electron-irradiation effects on solids is reported. The lowest temperature at the sample room is about 10 K or less. In a temperature region below 80 K, the sample temperature can be controlled within 0.05 K. (auth.)

  18. A possible anti-proliferative and anti-metastatic effect of irradiated riboflavin in solid tumours

    NARCIS (Netherlands)

    de Souza Queiroz, Karla Cristiana; Zambuzzi, Willian Fernando; de Souza, Ana Carolina Santos; da Silva, Rodrigo Augusto; Machado, Daisy; Justo, Giselle Zenker; Carvalho, Hernandes F.; Peppelenbosch, Maikel P.; Ferreira, Carmen Verissima

    2007-01-01

    Riboflavin is a potent photosensitizer as well as part of the vitamin B complex. Recently we demonstrated that the products generated by irradiation of riboflavin have potential as anti-leukaemic therapy. The possible action, however, of the riboflavin photoproducts in solid cancers has not been

  19. Photon emission from irradiated solids: Proceedings of the Werner Brandt workshop on penetration phenomena

    International Nuclear Information System (INIS)

    1986-11-01

    The workshop was concerned with photon emission from irradiated solids and the present record of the proceedings consists of material solicited from each participant. The results range from detailed and complete manuscripts to skeletal remnants of Vugraph transparencies. Individual papers have been cataloged separately

  20. Fine interstitial clusters as recombinators in decomposing solid solutions under irradiation

    International Nuclear Information System (INIS)

    Trushin, Yu.V.

    1991-01-01

    Behaviour of interstitial clusters and their roll in processes of radiation swelling of metals are described. It is shown that occurrence of coherent advanced precipitations during decomposition of solid solutions under irradiation leads to matrix supersaturation over interstitial atoms. This enhances recombination of unlike defects due to vacancy precipitation on fine interstitial clusters. Evaluation of cluster sizes was conducted

  1. Improved calculation of displacements per atom cross section in solids by gamma and electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Piñera, Ibrahin, E-mail: ipinera@ceaden.edu.cu [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, CEADEN, 30 St. 502, Playa 11300, Havana (Cuba); Cruz, Carlos M.; Leyva, Antonio; Abreu, Yamiel; Cabal, Ana E. [Centro de Aplicaciones Tecnológicas y Desarrollo Nuclear, CEADEN, 30 St. 502, Playa 11300, Havana (Cuba); Espen, Piet Van; Remortel, Nick Van [University of Antwerp, CGB, Groenenborgerlaan 171, 2020 Antwerpen (Belgium)

    2014-11-15

    Highlights: • We present a calculation procedure for dpa cross section in solids under irradiation. • Improvement about 10–90% for the gamma irradiation induced dpa cross section. • Improvement about 5–50% for the electron irradiation induced dpa cross section. • More precise results (20–70%) for thin samples irradiated with electrons. - Abstract: Several authors had estimated the displacements per atom cross sections under different approximations and models, including most of the main gamma- and electron-material interaction processes. These previous works used numerical approximation formulas which are applicable for limited energy ranges. We proposed the Monte Carlo assisted Classical Method (MCCM), which relates the established theories about atom displacements to the electron and positron secondary fluence distributions calculated from the Monte Carlo simulation. In this study the MCCM procedure is adapted in order to estimate the displacements per atom cross sections for gamma and electron irradiation. The results obtained through this procedure are compared with previous theoretical calculations. An improvement in about 10–90% for the gamma irradiation induced dpa cross section is observed in our results on regard to the previous evaluations for the studied incident energies. On the other hand, the dpa cross section values produced by irradiation with electrons are improved by our calculations in about 5–50% when compared with the theoretical approximations. When thin samples are irradiated with electrons, more precise results are obtained through the MCCM (in about 20–70%) with respect to the previous studies.

  2. Computer codes for simulating atomic-displacement cascades in solids subject to irradiation

    International Nuclear Information System (INIS)

    Asaoka, Takumi; Taji, Yukichi; Tsutsui, Tsuneo; Nakagawa, Masayuki; Nishida, Takahiko

    1979-03-01

    In order to study atomic displacement cascades originating from primary knock-on atoms in solids subject to incident radiation, the simulation code CASCADE/CLUSTER is adapted for use on FACOM/230-75 computer system. In addition, the code is modified so as to plot the defect patterns in crystalline solids. As other simulation code of the cascade process, MARLOWE is also available for use on the FACOM system. To deal with the thermal annealing of point defects produced in the cascade process, the code DAIQUIRI developed originally for body-centered cubic crystals is modified to be applicable also for face-centered cubic lattices. By combining CASCADE/CLUSTER and DAIQUIRI, we then prepared a computer code system CASCSRB to deal with heavy irradiation or saturation damage state of solids at normal temperature. Furthermore, a code system for the simulation of heavy irradiations CASCMARL is available, in which MARLOWE code is substituted for CASCADE in the CASCSRB system. (author)

  3. Response and recovery kinetics of a solid tumour after irradiation

    International Nuclear Information System (INIS)

    Rowley, R.; Hopkins, H.A.; Ritenour, E.R.; Looney, W.B.

    1980-01-01

    The effects of local tumour radiation over the dose range 7.5-30 Gy on the growth and cell kinetics of rat hepatoma H-4-II-E have been investigated. A plot of growth delays against log surviving fraction was linear below a fraction of 0.03, but failed to extrapolate to the origin. Following a single dose of 15 Gy to the tumour, DNA-precursor incorporation, labelling and mitotic indices were depressed for 7 days. Tumour cellularity, measured as DNA/g tumour was reduced and the rate of increase of total clonogenic cells slower than after complete tumour recovery. From Day 7 to Day 9 all indices of proliferation recovered to about control levels, clonogenic cell numbers increased more rapidly and tumour cellularity was restored. Repopulation of the tumour therefore appeared to take place mainly after Day 7. Incorporation of [ 3 H]-TdR into tumour DNA reached twice the control values on Day 9. The rate of tumour growth accelerated after the initial decrease, and maximum tumour growth rate was also twice the control values on Day 13. Accelerated growth rates in irradiated tumours, above those of control tumours, occurred 10-16 days after treatment. The effectiveness of sequential therapy may therefore be improved if given during this period of accelerated tumour growth. (author)

  4. Lactic-fermented egg white reduced serum cholesterol concentrations in mildly hypercholesterolemic Japanese men: a double-blind, parallel-arm design.

    Science.gov (United States)

    Matsuoka, Ryosuke; Usuda, Mika; Masuda, Yasunobu; Kunou, Masaaki; Utsunomiya, Kazunori

    2017-05-30

    Lactic-fermented egg white (LE), produced by lactic acid fermentation of egg white, is an easy-to-consume form of egg white. Here we assessed the effect of daily consumption of LE for 8 weeks on serum total cholesterol (TC) levels. The study followed a double-blind, parallel-arm design and included 88 adult men with mild hypercholesterolemia (mean ± standard error) serum TC levels, 229 ± 1.6 mg/dL; range, 204-259 mg/dL). The subjects were randomly divided into three groups, which consumed LE containing 4, 6, or 8 g of protein daily for 8 weeks. Blood samples were collected before starting LE consumption (baseline) and at 4 and 8 weeks to measure serum TC and low-density lipoprotein cholesterol (LDL-C) levels. After 8 weeks of consumption, serum TC levels in the 8 g group decreased by 11.0 ± 3.7 mg/dL, a significant decrease compared to baseline (p < 0.05) and a significantly greater decrease than for the 4 g group (3.1 ± 3.4 mg/dL; p < 0.05). Serum LDL-C levels in the 8 g group decreased by 13.7 ± 3.1 mg/dL, again a significant decrease compared with baseline (p < 0.05) and a significantly greater decrease than that for the 4 g group (2.1 ± 2.9 mg/dL; p < 0.05). Consumption of LE for 8 weeks at a daily dose of 8 g of proteins reduced serum TC and LDL-C levels in men with mild hypercholesterolemia, suggesting this may be effective in helping to prevent arteriosclerotic diseases. This clinical trial was retrospectively registered with the Japan Medical Association Center for Clinical Trials, (JMA-IIA00279; registered on 13/03/2017; https://dbcentre3.jmacct.med.or.jp/JMACTR/App/JMACTRE02_04/JMACTRE02_04.aspx?kbn=3&seqno=6530 ).

  5. Neutron irradiation characteristic tests of oxygen sensors using zirconia solid electrolyte

    International Nuclear Information System (INIS)

    Hiura, Nobuo; Endou, Yasuichi; Yamaura, Takayuki; Niimi, Motoji; Hoshiya, Taiji; Saito, Junichi; Souzawa, Shizuo; Ooka, Norikazu; Kobiyama, Mamoru.

    1997-03-01

    In the Department of JMTR of Japan Atomic Energy Research Institute (JAERI), the in-situ measuring technique of oxygen potential has been being developed to study the chemical behavior of high burn-up fuel base-irradiated in the Light Water Reactor. In this test for development of the technique, oxygen sensors using zirconia solid electrolyte stabilized by MgO, CaO and Y 2 O 3 , named MSZ, CSZ and YSZ, respectively, were irradiated by neutrons in the Japan Materials Testing Reactor (JMTR) of JAERI and the characteristics of electromotive force of these sensors under and after irradiation were discussed. From the experimental results, the electromotive force of YSZ sample under irradiation decreased with an increase in irradiation fluence within a range of neutron fluence (E>1 MeV) up to 1 x 10 23 m -2 . The electromotive force of MSZ sensor irradiated with neutron fluences (E>1 MeV) up to 9 x 10 21 m -2 was almost equal to the theoretical value of the electromotive force. It was shown that after irradiation, a decrease in the electromotive force of CSZ sensor was smaller than those of MSZ and YSZ sensors, although the electromotive forces of MSZ, CSZ and YSZ sensors were smaller than the theoretical value. (author)

  6. EPR of gamma irradiated solid sucrose and UV spectra of its solution. An attempt for calibration of solid state/EPR dosimetry

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Karakirova, Y.

    2007-01-01

    A simple new approach for independent calibration of solid state/EPR (SS/EPR) dosimetry system is reported. It is based on the fact that: (i) gamma-irradiation of solid sucrose (sugar) induces stable EPR detectable free radicals accompanied by UV detectable brown colour stable in the solid state and in solution; (ii) both the EPR intensity of gamma-irradiated solid sucrose and its solution UV absorbance linearly depend on the absorbed dose high energy radiation and may be independently used for dosimetric purpose; (iii) UV spectrometers are calibrated. The correlation between EPR response and absorbed dose radiation of solid sucrose and UV absorption of its solutions is used in the present communication for calibration purpose. The procedure of sucrose extraction from sucrose-paraffin dosimeters is described. The calibration procedure may be applied to any other (alanine, self-calibrated, etc.) SS/EPR dosimeters, simultaneously irradiated with sucrose

  7. Irradiation specifically sensitises solid tumour cell lines to TRAIL mediated apoptosis

    International Nuclear Information System (INIS)

    Marini, Patrizia; Schmid, Angelika; Jendrossek, Verena; Faltin, Heidrun; Daniel, Peter T; Budach, Wilfried; Belka, Claus

    2005-01-01

    TRAIL (tumor necrosis factor related apoptosis inducing ligand) is an apoptosis inducing ligand with high specificity for malignant cell systems. Combined treatment modalities using TRAIL and cytotoxic drugs revealed highly additive effects in different tumour cell lines. Little is known about the efficacy and underlying mechanistic effects of a combined therapy using TRAIL and ionising radiation in solid tumour cell systems. Additionally, little is known about the effect of TRAIL combined with radiation on normal tissues. Tumour cell systems derived from breast- (MDA MB231), lung- (NCI H460) colorectal- (Colo 205, HCT-15) and head and neck cancer (FaDu, SCC-4) were treated with a combination of TRAIL and irradiation using two different time schedules. Normal tissue cultures from breast, prostate, renal and bronchial epithelia, small muscle cells, endothelial cells, hepatocytes and fibroblasts were tested accordingly. Apoptosis was determined by fluorescence microscopy and western blot determination of PARP processing. Upregulation of death receptors was quantified by flow cytometry. The combined treatment of TRAIL with irradiation strongly increased apoptosis induction in all treated tumour cell lines compared to treatment with TRAIL or irradiation alone. The synergistic effect was most prominent after sequential application of TRAIL after irradiation. Upregulation of TRAIL receptor DR5 after irradiation was observed in four of six tumour cell lines but did not correlate to tumour cell sensitisation to TRAIL. TRAIL did not show toxicity in normal tissue cell systems. In addition, pre-irradiation did not sensitise all nine tested human normal tissue cell cultures to TRAIL. Based on the in vitro data, TRAIL represents a very promising candidate for combination with radiotherapy. Sequential application of ionising radiation followed by TRAIL is associated with an synergistic induction of cell death in a large panel of solid tumour cell lines. However, TRAIL receptor

  8. Small interstitial clusters as opposite defect recombinators in decomposing solid solutions under irradiation

    International Nuclear Information System (INIS)

    Orlov, A.N.; Trushin, Yu.V.

    1988-01-01

    An attempt was made to make allowance for the role of binary and ternary interstitials in the kinetics of radiation point defects both in the presence and in the absence of coherent preseparation. It is shown that in solid solutions, decomposing under irradiation, recombination with binary and ternary interstitials proceeds more quickly than directly, and this difference is more pronounced (from 2 up to 20 time growth) due to defect flow for preseparation at the stage of coherent preseparation formation

  9. Formation of fine solid particles from aqueous solutions of sodium chloropalladate by gamma-ray irradiation

    International Nuclear Information System (INIS)

    Hatada, Motoyoshi; Fujita, Iwao; Korekawa, Kei-ichi.

    1994-10-01

    Studies have been carried out on the radiation chemical formation of palladium fine particles in argon saturated aqueous solutions of sodium chloropalladate without organic stabilizer. The solutions were irradiated with gamma-rays from a cobalt gamma-ray source and the irradiated solutions were subjected to the dynamic light scattering analysis for the particle diameter measurements, and to the UV-visible optical absorption spectroscopy for the measurements of turbidity (absorption at 700 nm) and remaining chloropalladate ion concentrations in the solution. In the solution of pH = 1.95 by HCl, the turbidity increased after the irradiation and then decreased with time. The concentration of remaining palladate ion in the solution decreased by the irradiation, but it gradually increased with time after the irradiation. These phenomena were qualitatively explained by the reaction scheme in that a precursor to the solid particles still exists in the solution after the irradiation was terminated, and that intermediates including the precursor reacted with chloride ion to re-form chloropalladate ions. The average diameter of the particles after the irradiation was ca. 20 nm and it increased with time to 40 nm at 2.75 kGy, and to 80 nm at 8.25 kGy absorption of radiation. The solution of pH = 0.65 by HCl was found to give lower yields of particles than those observed for the solution of pH = 1.95, and to give the particles of diameters about 150-200 nm. In the solution containing HClO 4 instead of HCl, palladium particles were also formed by the irradiation, whereas no backward reaction after the irradiation was observed due to the low concentration of chloride ion in the solution. The average diameter of the particles after the irradiation was about 300 nm and increased with time after the irradiation to a final values which was found to depend on pH of the solution and dose. (author)

  10. Thermodynamic pathways to melting, ablation, and solidification in absorbing solids under pulsed laser irradiation

    International Nuclear Information System (INIS)

    Lorazo, Patrick; Lewis, Laurent J.; Meunier, Michel

    2006-01-01

    The thermodynamic pathways involved in laser irradiation of absorbing solids are investigated in silicon for pulse durations of 500 fs and 100 ps. This is achieved by accounting for carrier and atom dynamics within a combined Monte Carlo and molecular-dynamics scheme and simultaneously tracking the time evolution of the irradiated material in ρ-T-P space. Our simulations reveal thermal changes in long-range order and state of aggregation driven, in most cases, by nonequilibrium states of rapidly heated or promptly cooled matter. Under femtosecond irradiation near the ablation threshold, the system is originally pulled to a near-critical state following rapid ( -12 s) disordering of the mechanically unstable crystal and isochoric heating of the resulting metallic liquid. The latter is then adiabatically cooled to the liquid-vapor regime where phase explosion of the subcritical, superheated melt is initiated by a direct conversion of translational, mechanical energy into surface energy on a ∼10 -12 -10 -11 s time scale. At higher fluences, matter removal involves, instead, the fragmentation of an initially homogeneous fluid subjected to large strain rates upon rapid, supercritical expansion in vacuum. Under picosecond irradiation, homogeneous and, at later times, heterogeneous melting of the superheated solid are followed by nonisochoric heating of the molten metal. In this case, the subcritical liquid material is subsequently cooled onto the binodal by thermal conduction and explosive boiling does not take place; as a result, ablation is associated with a ''trivial'' fragmentation process, i.e., the relatively slow expansion and dissociation into liquid droplets of supercritical matter near thermodynamic equilibrium. This implies a liquid-vapor equilibration time of ∼10 -11 -10 -10 s and heating along the binodal under nanosecond irradiation. Solidification of the nonablated, supercooled molten material is eventually observed on a ∼10 -11 -10 -9 s time scale

  11. Passive maternal exposure to environmental microbes selectively modulates the innate defences of chicken egg white by increasing some of its antibacterial activities.

    Science.gov (United States)

    Bedrani, Larbi; Helloin, Emmanuelle; Guyot, Nicolas; Réhault-Godbert, Sophie; Nys, Yves

    2013-06-07

    Egg defence against bacterial contamination relies on immunoglobulins (IgY) concentrated in the yolk and antimicrobial peptides/proteins predominantly localized in the egg white (EW). Hens contaminated with pathogenic microorganisms export specific IgYs to the egg (adaptative immunity). No evidence of such regulation has been reported for the antimicrobial peptides/proteins (innate immunity) which are preventively secreted by the hen oviduct and are active against a large range of microbes. We investigated whether the egg innate defences can be stimulated by the environmental microbial contamination by comparing the antimicrobial activity of EW of hens raised in three extreme breeding conditions: Germ-free (GF), Specific Pathogen Free (SPF) and Conventional (C) hens. The difference in the immunological status of GF, SPF and C hens was confirmed by the high stimulation of IL-1β, IL-8 and TLR4 genes in the intestine of C and SPF groups. EW from C and SPF groups demonstrated higher inhibitory effect against Staphylococcus aureus (13 to 18%) and against Streptococcus uberis (31 to 35%) as compared to GF but showed similar activity against Salmonella Enteritidis, Salmonella Gallinarum, Escherichia coli and Listeria monocytogenes. To further investigate these results, we explored putative changes amongst the three main mechanisms of egg antimicrobial defence: the sequestration of bacterial nutrients, the inactivation of exogenous proteases and the direct lytic action on microorganisms. Lysozyme activity, chymotrypsin-, trypsin- and papain-inhibiting potential of EW and the expression of numerous antimicrobial genes were not stimulated suggesting that these are not responsible for the change in anti-S. aureus and anti-S. uberis activity. Moreover, whereas the expression levels of IL-1β, IL-8 and TLR4 genes were modified by the breeding conditions in the intestine of C and SPF groups they were not modified in the magnum where egg white is formed. Altogether, these data

  12. Is the Spencer-Attix cavity equation applicable for solid-state detectors irradiated in megavoltage electron beams?

    International Nuclear Information System (INIS)

    Mobit, P.N.; Sandison, G.A.; Calgary Univ., AB

    2001-01-01

    The applicability of the Spencer-Attix cavity equation in determining absorbed doses in water using solid state detectors irradiated by megavoltage electron beams have been examined. The calculations were performed using the EGSnrc Monte Carlo code. This work is an extension of a recently published article examining the perturbation of dose by solid state detectors in megavoltage electron beams. (orig.)

  13. Ion beam irradiation as a tool to improve the ionic conductivity in solid polymer electrolyte systems

    Energy Technology Data Exchange (ETDEWEB)

    Manjunatha, H., E-mail: h-manjunath@blr.amrita.edu; Kumaraswamy, G. N. [Department of Physics, Amrita Vishwa Vidyapeetham, Bengaluru-560 035 (India); Damle, R. [Department of Physics, Bangalore University, Bengaluru-560 056 (India)

    2016-05-06

    Solid polymer electrolytes (SPEs) have potential applications in solid state electronic and energy devices. The optimum conductivity of SPEs required for such applications is about 10{sup −1} – 10{sup −3} Scm{sup −1}, which is hard to achieve in these systems. It is observed that ionic conductivity of SPEs continuously increase with increasing concentration of inorganic salt in the host polymer. However, there is a critical concentration of the salt beyond which the conductivity of SPEs decreases due to the formation of ion pairs. In the present study, solid polymer thin films based on poly (ethylene oxide) (PEO) complexed with NaBr salt with different concentrations have been prepared and the concentration at which ion pair formation occurs in PEO{sub x}NaBr is identified. The microstructure of the SPE with highest ionic conductivity is modified by irradiating it with low energy O{sup +1} ion (100 keV) of different fluencies. It is observed that the ionic conductivity of irradiated SPEs increases by one order in magnitude. The increase in ionic conductivity may be attributed to the enhanced segmental motion of the polymer chains due to radiation induced micro structural modification.

  14. Enhanced mass transfer during solid-liquid extraction of gamma-irradiated red beetroot

    International Nuclear Information System (INIS)

    Nayak, Chetan A.; Chethana, S.; Rastogi, N.K.; Raghavarao, K.S.M.S.

    2006-01-01

    The exposure to gamma-irradiation pretreatment increases cell wall permeabilization, resulting in loss of turgor pressure, which led to the increase of extractability of betanin from red beetroot. The degree of extraction of betanin was investigated using gamma irradiation as a pretreatment prior to the solid-liquid extraction process and compared with control beetroot samples. The beetroot subjected to different doses of gamma irradiation (2.5, 5.0, 7.5, 10.0 kGy) and control was dipped in an acetic acid medium (1% v/v) to extract the betanin. The diffusion coefficients for betanin as well as ionic component were estimated considering Fickian diffusion. The results indicated an increase in the diffusion coefficient of betanin (0.302x10 -9 -0.463x10 -9 m 2 /s) and ionic component (0.248x10 -9 -0.453x10 -9 m 2 /s) as the dose rate increased (from 2.5 to 10.0 kGy). The degradation constant was found to increase (0.050-0.079 min -1 ) with an increase gamma-irradiation doses (2.5-10.0 kGy), indicating lower stability of the betanin as compared to control sample at 65 deg. C

  15. [Novel irradiation techniques in the treatment of solid tumours. Radiotherapy for metastases].

    Science.gov (United States)

    Mayer, Arpád; Póti, Zsuzsa

    2014-02-23

    Novel developments in percutaneous radiotherapy, such as positron emission tomography/computed tomography, adaptive radiation planning, intensity modulation radiotherapy and intensity modulated arc therapy (RapidArc), as well as the newer generation of image control (cone-beam computed tomography) and image guided radiotherapy ensure increased dosages of planning target volume and clinical target volume of solid tumours without damaging surrounding tissues and providing maximal protection. By raising the dosages of planned target volume and clinical target volume, these novel technical developments have created new indications in the treatment of solid tumours. With the aid of the cone-beam computed tomography and image guided radiotherapy the organ metastasis (lung, liver, spinal cord) and the primary tumour can be treated safety and effectively. Hypofractionation, dose escalation and the use of stereotactic devices can probably decrease radiation damage. The authors review the most common forms of evidence-based fractionation schemes used in irradiation therapy.

  16. The accumulation of disorder, subject to saturation and sputter limitation, in ion irradiated solids

    International Nuclear Information System (INIS)

    Carter, G.; Webb, R.; Collins, R.

    1978-01-01

    The depth distribution of disorder and the depth integrated disorder produced by ion irradiation of solids is analysed theoretically as a function of increasing ion fluence when disorder saturation processes operate at all depths and the solid surface is continuously uniformly eroded by sputtering. The resulting defining equations are evaluated numerically for a Gaussian approximation to the disorder depth function with parameters appropriate to low, equal and high projectile:substrate mass ratio conditions, for several values of sputtering coefficient and effective atom displacement energy. It is shown that the form, if not the magnitude, of the integrated disorder/projectile fluence function is only weakly dependent upon these parameters. More meaningful comparison with depth resolved disorder functions is, however, possible and such a comparison is made for 100 keV Sb projectiles on a Si substrate. (author)

  17. Effect of inclusion of hydroxycinnamic and chlorogenic acids from green coffee bean in β-cyclodextrin on their interactions with whey, egg white and soy protein isolates.

    Science.gov (United States)

    Budryn, Grażyna; Pałecz, Bartłomiej; Rachwał-Rosiak, Danuta; Oracz, Joanna; Zaczyńska, Donata; Belica, Sylwia; Navarro-González, Inmaculada; Meseguer, Josefina María Vegara; Pérez-Sánchez, Horacio

    2015-02-01

    The aim of the study was to characterise the interactions of hydroxycinnamic and chlorogenic acids (CHAs) from green coffee, with isolates of proteins from egg white (EWP), whey (WPC) and soy (SPI), depending on pH and temperature. The binding degree was determined by liquid chromatography coupled to a diode array detector and an ultrahigh resolution hybrid quadruple-time-of-flight mass spectrometer with ESI source (LC-QTOF-MS/MS). As a result of binding, the concentration of CHAs in proteins ranged from 9.44-12.2, 11.8-13.1 and 12.1-14.4g/100g for SPI, WPC and EWP, respectively. Thermodynamic parameters of protein-ligand interactions were determined by isothermal titration calorimetry (ITC) and energetics of interactions at the atomic level by molecular modelling. The amount of CHAs released during proteolytic digestion was in the range 0.33-2.67g/100g. Inclusion of CHAs with β-cyclodextrin strongly limited these interactions to a level of 0.03-0.06g/100g. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. An Exploration of the Calcium-Binding Mode of Egg White Peptide, Asp-His-Thr-Lys-Glu, and In Vitro Calcium Absorption Studies of Peptide-Calcium Complex.

    Science.gov (United States)

    Sun, Na; Jin, Ziqi; Li, Dongmei; Yin, Hongjie; Lin, Songyi

    2017-11-08

    The binding mode between the pentapeptide (DHTKE) from egg white hydrolysates and calcium ions was elucidated upon its structural and thermodynamics characteristics. The present study demonstrated that the DHTKE peptide could spontaneously bind calcium with a 1:1 stoichiometry, and that the calcium-binding site corresponded to the carboxyl oxygen, amino nitrogen, and imidazole nitrogen atoms of the DHTKE peptide. Moreover, the effect of the DHTKE-calcium complex on improving the calcium absorption was investigated in vitro using Caco-2 cells. Results showed that the DHTKE-calcium complex could facilitate the calcium influx into the cytosol and further improve calcium absorption across Caco-2 cell monolayers by more than 7 times when compared to calcium-free control. This study facilitates the understanding about the binding mechanism between peptides and calcium ions as well as suggests a potential application of egg white peptides as nutraceuticals to improve calcium absorption.

  19. Cascade diffusion theory of sink capture fluctuations during irradiation of a solid

    International Nuclear Information System (INIS)

    Mansur, L.K.; Brailsford, A.D.; Coghlan, W.A.

    1985-01-01

    Fluctuations in the number of defects captured by sinks in an irradiated solid, that arise because of the stochastic nature of collision cascade events, are analyzed. Two types of sinks are considered, cavities (or voids) and dislocations. The importance of the physical size of the sink is emphasized, as also is the magnitude of the fluctuations in defect capture relative to the behavior of its statistical mean. In particular, it is shown that the ratio of the variance to the mean, for either a cavity or a dislocation segment, decreases rapidly as overall steady state is approached. Further analytical and computational aspects of a shell model that we introduced earlier are analyzed. The relationship of this model to a truly random system is established, and additional calculations are presented to exemplify some of the features predicted by the mathematical analysis. Importance functions describing the spatial origins of the point defects contributing to the average concentration and flux are described. The probabilities of special types of cascade coincidences are developed. The application of the present formalism to the problems of void nucleation, and dislocation climb over localized obstacles, in irradiated solids is indicated

  20. Solid solutions of gadolinium doped zinc oxide nanorods by combined microwave-ultrasonic irradiation assisted crystallization

    Science.gov (United States)

    Kiani, Armin; Dastafkan, Kamran; Obeydavi, Ali; Rahimi, Mohammad

    2017-12-01

    Nanocrystalline solid solutions consisting of un-doped and gadolinium doped zinc oxide nanorods were fabricated by a modified sol-gel process utilizing combined ultrasonic-microwave irradiations. Polyvinylpyrrolidone, diethylene glycol, and triethylenetetramine respectively as capping, structure directing, and complexing agents were used under ultrasound dynamic aging and microwave heating to obtain crystalline nanorods. Crystalline phase monitoring, lattice parameters and variation, morphology and shape, elemental analysis, functional groups, reducibility, and the oxidation state of emerged species were examined by PXRD, FESEM, TEM, EDX, FTIR, micro Raman, H2-TPR, and EPR techniques. Results have verified that irradiation mechanism of gelation and crystallization reduces the reaction time, augments the crystal quality, and formation of hexagonal close pack structure of Wurtzite morphology. Besides, dissolution of gadolinium within host lattice involves lattice deformation, unit cell distortion, and angular position variation. Structure related shape and growth along with compositional purity were observed through microscopic and spectroscopic surveys. Furthermore, TPR and EPR studies elucidated more detailed behavior upon exposure to the exerted irradiations and subsequent air-annealing including the formed oxidation states and electron trapping centers, presence of gadolinium, zinc, and oxygen disarrays and defects, as well as alteration in the host unit cell via gadolinium addition.

  1. Effect of radiation quality on radical formation in ion-irradiated solid alanine

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Hitoshi; Ichikawa, Tsuneki; Yoshida, Hiroshi [Hokkaido Univ., Sapporo (Japan); Namba, Hideki; Taguchi, Mitsumasa; Kojima, Takuji

    1997-03-01

    Radical formation in solid alanine irradiated with H{sup +} and He{sup +} ions of 0.5-3.0 MeV and with heavy ions of hundreds of MeV was examined by the ESR method. Radical yield is constant below a critical fluence, and the yield decreases above the fluence. The critical fluence for the H{sup +} and He{sup +} ions is about 10{sup 12} ions cm{sup -2}, while the critical fluence for the heavy ions is 10{sup 10}-10{sup 11} ions cm{sup -2}. G-value of the radical formation (radicals per 100 eV absorbed dose) is obtained from the constant yield at the low fluences. The G-value depends on the radiation quality. This dependence is ascribed to the difference of local dose in the ion tracks. The fluence-yield curves were simulated with a model assuming cylindrical shape of ion tracks and dose-yield relationship for {gamma}-irradiation. This model well explains the fluence-yield curves for the ion irradiations. (author)

  2. Use of egg white protein powder based films fortified with sage and lemon balm essential oils in the storage of lor cheese

    Directory of Open Access Journals (Sweden)

    Gökhan Kavas

    2016-03-01

    Full Text Available Edible film was produced by adding 3 % sorbitol (w/v to egg white protein powder (EWPP. The first group of lor cheese samples was coated with a film fortified by sage essential oil (SEO and the second group of samples was coated with films enriched by adding lemon balm essential oil (BEO at various concentrations [0.5 %, 1 %, 2 % (v/v]. The films were labeled as EWPPSEO(0.5, EWPPSEO(1, EWPPSEO(2, EWPPBEO(0.5, EWPPBEO(1, EWPPBEO(2 to indicate the type and the concentration of the additive. The third batch of the lor cheese samples was coated exclusively with non-fortified EWPP and the fourth batch was uncoated. All of the cheese samples were artificially contaminated with Escherichia coli O157:H7 (E. coli O157:H7, Listeria monocytogenes (L. monocytogenes and Staphylococcus aureus (S. aureus. Viable cell counts of these species, yeasts and moulds were determined after the cheese production. All the samples were stored at +4 °C. Their physicochemical and microbiological properties were examined on the 1st, 7th, 15th and 30th day of the storage. Thereat significant (P0.05. Physicochemical and antibacterial properties were more significant in SEO at all concentrations compared to BEO. However, the antifungal effect of BEO was higher than that of SEO. The antifungal effect of BEO was the same at 1 % (v/v and 2 % (v/v concentrations. E. coli O157:H7 was the most resistant microorganism to the essential oils while L. monocytogenes was the most sensitive. EWPP showed a bacteriostatic effect on the microorganisms and bactericidal effects were determined on the 30th day of the storage against L. monocytogenes and yeast-moulds.

  3. Egg white powder-stabilised multiple (water-in-olive oil-in-water) emulsions as beef fat replacers in model system meat emulsions.

    Science.gov (United States)

    Öztürk, Burcu; Urgu, Müge; Serdaroğlu, Meltem

    2017-05-01

    Today, multiple emulsions are believed to have a considerable application potential in food industry. We aimed to investigate physical, chemical and textural quality characteristics of model system meat emulsions (MSME) in which beef fat (C) was totally replaced by 10% (E-10), 20% (E-20) or 30% (E-30) multiple emulsions (W 1 /O/W 2 ) prepared with olive oil and egg white powder (EWP). Incorporation of W 1 /O/W 2 emulsion resulted in reduced fat (from 11.54% to 4.01%), increased protein content (from 13.66% to 14.74%), and modified fatty acid composition, significantly increasing mono- and polyunsaturated fatty acid content and decreasing saturated fatty acid content. E-20 and E-30 samples had lower jelly and fat separation (5.77% and 5.25%) compared to C and E-10 (9.67% and 8.55%). W 1 /O/W 2 emulsion treatments had higher water-holding capacity (93.96-94.35%) than C samples (91.84%), and also showed the desired storage stability over time. Emulsion stability results showed that E-20 and E-30 samples had lower total expressible fluid (14.05% and 14.53%) and lower total expressible fat (5.06% and 5.33%) compared to C samples (19.13% and 6.09%). Increased concentrations of W 1 /O/W 2 emulsions led to alterations in colour and texture parameters. TBA values of samples were lower in W 1 /O/W 2 emulsion treatments than control treatment during 60 days of storage. Our results indicated that multiple emulsions prepared with olive oil and EWP had promising impacts on reducing fat, modifying the lipid composition and developing both technologically and oxidatively stable meat systems. These are the first findings concerning beef matrix fat replacement with multiple emulsions stabilised by EWP. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  4. Intra-Amniotic Administration (Gallus gallus) of Cicer arietinum and Lens culinaris Prebiotics Extracts and Duck Egg White Peptides Affects Calcium Status and Intestinal Functionality.

    Science.gov (United States)

    Hou, Tao; Kolba, Nikolai; Glahn, Raymond P; Tako, Elad

    2017-07-21

    Calcium (Ca) is one of the most abundant inorganic elements in the human body and has many important physiological roles. Prebiotics and bioactive peptides are two important substances used to promote calcium uptake. However, the difference in mechanisms of the calcium uptake from these two supplements is not clear. By using the Gallus gallus model and the intra-amniotic administration procedure, the aim of this study was to investigate whether Ca status, intestinal functionality, and health-promoting bacterial populations were affected by prebiotics extracted from chickpea and lentil, and duck egg white peptides (DPs). Eleven groups (non-injected; 18 MΩ H₂O; 4 mmol/L CaCl₂; 50 mg/mL chickpea + 4 mmol/L CaCl₂; 50 mg/mL lentil + 4 mmol/L CaCl₂; 40 mg/mL DPs + 4 mmol/L CaCl₂; 5 mg/mL Val-Ser-Glu-Glu (VSEE) + 4 mmol/L CaCl₂; 50 mg/mL chickpea; 50 mg/mL lentil; 40 mg/mL DPs; 5 mg/mL VSEE) were utilized. Upon hatch, blood, cecum, small intestine, liver and bone were collected for assessment of serum bone alkaline phosphate level (BALP), the relative abundance of intestinal microflora, expression of Ca-related genes, brush border membrane (BBM) functional genes, and liver and bone mineral levels, respectively. The BALP level increased in the presence of lentil, DPs and VSEE ( p Prebiotics and DPs beneficially affected the intestinal microflora and duodenal villus surface area. This research expands the understanding of the prebiotics' properties of chickpea and lentil extracts, and peptides' effects on calcium metabolism and gut health.

  5. Pressure-assisted cold denaturation of hen egg white lysozyme: the influence of co-solvents probed by hydrogen exchange nuclear magnetic resonance.

    Science.gov (United States)

    Vogtt, K; Winter, R

    2005-08-01

    COSY proton nuclear magnetic resonance was used to measure the exchange rates of amide protons of hen egg white lysozyme (HEWL) in the pressure-assisted cold-denatured state and in the heat-denatured state. After dissolving lysozyme in deuterium oxide buffer, labile protons exchange for deuterons in such a way that exposed protons are substituted rapidly, whereas "protected" protons within structured parts of the protein are substituted slowly. The exchange rates k obs were determined for HEWL under heat treatment (80 degrees C) and under high pressure conditions at low temperature (3.75 kbar, -13 degrees C). Moreover, the influence of co-solvents (sorbitol, urea) on the exchange rate was examined under pressure-assisted cold denaturation conditions, and the corresponding protection factors, P, were determined. The exchange kinetics upon heat treatment was found to be a two-step process with initial slow exchange followed by a fast one, showing residual protection in the slow-exchange state and P-factors in the random-coil-like range for the final temperature-denatured state. Addition of sorbitol (500 mM) led to an increase of P-factors for the pressure-assisted cold denatured state, but not for the heat-denatured state. The presence of 2 M urea resulted in a drastic decrease of the P-factors of the pressure-assisted cold denatured state. For both types of co-solvents, the effect they exert appears to be cooperative, i.e., no particular regions within the protein can be identified with significantly diverse changes of P-factors.

  6. Pressure-assisted cold denaturation of hen egg white lysozyme: the influence of co-solvents probed by hydrogen exchange nuclear magnetic resonance

    Directory of Open Access Journals (Sweden)

    K. Vogtt

    2005-08-01

    Full Text Available COSY proton nuclear magnetic resonance was used to measure the exchange rates of amide protons of hen egg white lysozyme (HEWL in the pressure-assisted cold-denatured state and in the heat-denatured state. After dissolving lysozyme in deuterium oxide buffer, labile protons exchange for deuterons in such a way that exposed protons are substituted rapidly, whereas "protected" protons within structured parts of the protein are substituted slowly. The exchange rates k obs were determined for HEWL under heat treatment (80ºC and under high pressure conditions at low temperature (3.75 kbar, -13ºC. Moreover, the influence of co-solvents (sorbitol, urea on the exchange rate was examined under pressure-assisted cold denaturation conditions, and the corresponding protection factors, P, were determined. The exchange kinetics upon heat treatment was found to be a two-step process with initial slow exchange followed by a fast one, showing residual protection in the slow-exchange state and P-factors in the random-coil-like range for the final temperature-denatured state. Addition of sorbitol (500 mM led to an increase of P-factors for the pressure-assisted cold denatured state, but not for the heat-denatured state. The presence of 2 M urea resulted in a drastic decrease of the P-factors of the pressure-assisted cold denatured state. For both types of co-solvents, the effect they exert appears to be cooperative, i.e., no particular regions within the protein can be identified with significantly diverse changes of P-factors.

  7. Protection of a protein against irradiation-induced degradation by additives in the solid state

    International Nuclear Information System (INIS)

    Shalaev, E.; Reddy, R.; Kimball, R.N.; Weinschenk, M.F.; Guinn, M.; Margulis, L.

    2003-01-01

    The impact of ionizing radiation on a globular protein (porcine somatotropin, pST) in the solid state was studied using rate of dissolution, high-performance liquid chromatography, and Electron spin resonance (ESR) in the presence of different additives. o-Vanillin stabilized pST against irradiation-induced degradation whereas effects of trolox and isopropyl alcohol were less significant. Stabilization effect of o-vanillin has been related to the energy transfer from pST molecules to the additive which was facilitated by formation of covalent bonds between o-vanillin and pST molecules. Anticorrelation between the level of free radicals and chemical degradation (i.e. degradation increased with decrease in a free radical level) was observed in the presence of o-vanillin

  8. Irradiation and accretion of solids in space based on observations of lunar rocks and grains

    International Nuclear Information System (INIS)

    Lal, D.

    1977-01-01

    Clues to a wide range of questions relating to the origin and evolution of the solar system and dynamic physical and electromagnetic processes occurring concurrently and in the past in our galaxy have been provided by a study of the lunar samples. This information is deduced from a variety of complementary physical and chemical evidence. In this presentation greatest emphasis is laid on information based on effects arising from interactions of low energy cosmic rays with lunar surface materials. The present discussions concern the nature of experimental data to date and implications thereof to the charged particle environment of the Moon, ancient magnetic fields and the nature of time scales involved in the irradiation and accretion of solids in space, based on lunar regolith dynamics. It becomes clear that there does not yet exist any consensus on the absolute values of charged particle or the meteorite fluxes, and also about the details of the evolution of the lunar regolith. The complex history of evolution of lunar material is slowly being understood and it is hoped that a great deal of quantitative information will soon be available which will in turn allow discussion of evolution of solid bodies in the solar system. (author)

  9. Inactivation of gram-negative bacteria in milk and banana juice by hen egg white and lambda lysozyme under high hydrostatic pressure.

    Science.gov (United States)

    Nakimbugwe, Dorothy; Masschalck, Barbara; Anim, Grace; Michiels, Chris W

    2006-10-15

    The effect of hen egg white lysozyme (HEWL) and bacteriophage lambda lysozyme (LaL) in combination with high pressure (HP) treatment on the inactivation of four gram-negative bacteria (Escherichia coli O157:H7, Shigella flexneri, Yersinia enterocolitica and Salmonella typhimurium), was studied in skim milk (pH 6.8; a(w) 0.997) and in banana juice (pH 3.8; a(w) 0.971). In the absence of lysozymes, S. flexneri was more sensitive to HP in milk than in banana juice, while the opposite was observed for the other three bacteria. In combination with HP treatment, LaL was more effective than HEWL on all bacteria in both milk and banana juice. Depending on the bacteria, inactivation levels in banana juice were increased from 0.4-2.7 log units by HP treatment alone to 3.6-6.5 log units in the presence of 224 U/ml LaL. Bacterial inactivation in milk was also enhanced by LaL but only by 0.5-2.1 log units. Under the experimental conditions used, LaL was more effective in banana juice than in milk, while the effectiveness of HEWL under the same conditions was not significantly affected by the food matrix. This effect could be ascribed to the low pH of the banana juice since LaL was also more effective on E. coli in buffer at pH 3.8 than at pH 6.8. Since neither LaL nor HEWL are enzymatically active at pH 3.8, we analysed bacterial lysis after HP treatment in the presence of these enzymes, and found that inactivation proceeds through a non-lytic mechanism at pH 3.8 and a lytic mechanism at pH 6.8. Based on these results, LaL may offer interesting perspectives for use as an extra hurdle in high pressure food preservation.

  10. The occurrence of recruitment supported from the finding of an increase in radiosensitivity of quiescent cells in solid tumors after fractionated irradiation with X-rays

    International Nuclear Information System (INIS)

    Masunaga, Shinichiro; Ono, Koji; Kinashi, Yuko; Suzuki, Minoru; Akaboshi, Mitsuhiko

    1998-01-01

    We examined the behavior of quiescent cells in solid tumors irradiated twice at various intervals with X-rays, using our recently developed method for selectively detecting the response of quiescent cells in solid tumors. To determine the labeling indices of tumors at the second irradiation, each mouse group included mice that were continuously administered BrdU until just before the second irradiation using mini-osmotic pumps which had been implanted before the first irradiation. Radiosensitivity of total tumor cells at the second irradiation decreased in proportion to the increase in interval time. However, radiosensitivity of quiescent cells was raised with increase in the interval time. In addition, the labeling index at the second irradiation was higher than that at the first irradiation. These findings supported the occurrence of recruitment from quiescent to proliferating state during fractionated irradiation. (author)

  11. Pulse radiolysis studies of intramolecular electron transfer in model peptides and proteins. 7. Trp -> TyrO radical transformation in hen egg-white lysozyme. Effects of pH, temperature, Trp62 oxidation and inhibitor binding

    DEFF Research Database (Denmark)

    Bobrowski, K.; Holcman, J.; Poznanski, J.

    1997-01-01

    Intramolecular long-range electron transfer (LRET) in hen egg-white lysozyme (HEWL) accompanying Trp --> TyrO radical transformation was investigated in aqueous solution by pulse radiolysis as a function of pH (5.2-7.4) and temperature (283-328K). The reaction was induced by highly selective...... below its denaturation temperature. Selective oxidation by ozone of the Trp62 indole side-chain in HEWL to N'-formylkynurenine (NFKyn62-HEWL) caused a large drop in the initial yield of Trp(.) radicals, G(Trp(.))(i). This was accompanied by a relatively small decrease in k(5) but selective oxidation...

  12. Long-Range Electron Effects upon Irradiation of Molecular Solids and Polymers

    International Nuclear Information System (INIS)

    Feldman, V.I.

    2006-01-01

    Long-range electron effects are responsible for specific localization and selectivity of the radiation-induced chemical transformations occurring in molecular solids and polymers, when the classic diffusion mobility is essentially restricted. In particullar, understanding of the effects of this kind may be of key significance for establishing new ways to control the radiation sensitivity of macromolecules and organized polymeric systems, nanomaterials and biopolymers. This talk will present an overview of model studies of the long-range electron effects with the characteristic scale from several angstroms to ten nanometers. The following aspects of the problem will be analyzed: (1) Positive hole delocalization in ionized molecules. This phenomenon has been demonstrated experimentally and confirmed by quantum chemical calculations for a number of various-type molecules (alkanes, conjugated polyenes, bifunctional compounds). The effective delocalization length was found to be up to 2 nm (or even larger). The role of this effect in site-selective radiation chemistry will be discussed in the frame of concepts of distributed reactivity and 'switching' between delocalized and localized states. (2) Trap-to-trap positive hole and electron migration between isolated molecules or functional groups. The characteristic distance for this process was estimated to be 2 to 4 nm. Special impact will be made on the possible role of this process in selection of specific isomers or conformers upon irradiation of complex systems and macromolecules. (3) The effects of long-range scavenging of low-energy secondary electrons in polymers and organized polymeric systems. As revealed by model experiments, the radius of electron capture in solid polymers may be in the range of 1 to 10 nm. Possible implications of scavenging effects for controlling the radiation chemistry of polymers and organized polymeric systems will be considered

  13. Some structural characteristics of gamma-irradiated pure and Li2O-doped NiO solids

    International Nuclear Information System (INIS)

    Ramadan, A.A.; Dessouki, A.M.

    1989-01-01

    The induced structural changes, due to Li 2 O-doping (2.5 mol%) and γ-irradiation (10-80 Mrad), of NiO were investigated by XRD analyses. The results obtained revealed that lithium-doping resulted in a significant increase in the internal strain and a decrease in lattice parameter. These changes were explained in terms of creation of Ni 3+ ions in the doped solids. γ-Irradiation of pure and doped solids effected a decrease in both crystallite size and microstrain upon subjecting to doses of 20 and 30 Mrad. Higher doses induced an increase in both parameters in the case of pure NiO and a further decrease in case of the doped solid. These results were attributed to splitting of the large strained crystallites and to an activated sintering of the small strained ones. γ-Irradiation effected also an increase in the lattice parameters of pure and doped solids due to removal of some excess oxygen with subsequent decrease in the concentration of Ni 3+ ions. (author)

  14. Criteria for formation of low-frequency sound under wide-aperture repetitively pulsed laser irradiation of solids

    International Nuclear Information System (INIS)

    Tishchenko, V N; Posukh, V G; Gulidov, A I; Zapryagaev, V I; Pavlov, A A; Boyarintsev, Ye L; Golubev, M P; Kavun, I N; Melekhov, A V; Golobokova, L S; Miroshnichenko, I B; Pavlov, Al A; Shmakov, A S

    2011-01-01

    The criteria for merging shock waves formed by optical breakdowns on the surface of solids have been investigated. Targets made of different materials were successively irradiated by two CO 2 -laser pulses with energies up to 200 J and a duration of ∼1 μs. It is shown that the criteria under consideration can be applied to different targets and irradiation regimes and make it possible to calculate the parameters of repetitively pulsed laser radiation that are necessary to generate low-frequency sound and ultrasound in air.

  15. Surface composition variation and high-vacuum performance of DLC/ILs solid-liquid lubricating coatings: Influence of space irradiation

    International Nuclear Information System (INIS)

    Liu Xiufang; Wang Liping; Pu Jibin; Xue Qunji

    2012-01-01

    In this paper, we fabricated a DLC/ionic liquid (DLC/ILs) solid-liquid lubricating coating and investigated the effect of atomic oxygen (AO), ultraviolet (UV), proton and electron irradiations on composition, structure, morphology and tribological properties of the DLC/ILs solid-liquid lubricating coatings. A ground-based simulation facility was employed to carry out the irradiation experiments. X-ray photoelectron spectroscope (XPS), Raman spectra, and Fourier Transform Infrared Spectroscopy (FTIR) were used to analyzed the structure and composition changes of DLC film and IL lubricant before and after irradiations. The tribological behavior of the DLC/ILs solid-liquid lubricating coating before and after irradiations was investigated by a vacuum tribometer with the pressure of 10 -5 Pa. The experimental results revealed that irradiations induced the structural changes, including oxidation, bond break and crosslinking reactions of DLC film and IL lubricant. The damage of proton and AO irradiations to lubricating materials were the most serious, and UV irradiation was the slightest. After irradiations, the friction coefficient of the solid-liquid lubricating coatings decreased (except for AO irradiation), but the disc wear rate increased compared with non-irradiation coatings.

  16. Irradiated ignition over solid materials in reduce pressure environment: Fire safety issue in man-made enclosure system

    Science.gov (United States)

    Nakamura, N.; Aoki, A.

    Effects of ambient pressure and oxygen yield on irradiated ignition characteristics over solid combustibles have been studied experimentally Aim of the present study is to elucidate the flammability and chance of fire in depressurized enclosure system and give ideas for the fire safety and fire fighting strategies in such environment Thin cellulosic paper is considered as the solid combustible since cellulose is one of major organic compounds and flammables in the nature Applied atmosphere consists of inert gas either CO2 or N2 and oxygen and various mixture ratios are of concerned Total ambient pressure level is varied from 0 1MPa standard atmospheric pressure to 0 02MPa Ignition is initiated by external thermal flux exposed into the solid surface as a model of unexpected thermal input to initiate the localized fire Thermal degradation of the solid induces combustible gaseous products e g CO H2 or other low class of HCs and the gas mixes with ambient oxygen to form the combustible mixture over the solid Heat transfer from the hot irradiated surface into the mixture accelerates the local exothermic reaction in the gas phase and finally thermal runaway ignition is achieved Ignition event is recorded by high-speed digital video camera to analyze the ignition characteristics Flammable map in partial pressure of oxygen Pox and total ambient pressure Pt plane is made to reveal the fire hazard in depressurized environment Results show that wider flammable range is obtained depending on the imposed ambient

  17. Frequency Distribution of Second Solid Cancer Locations in Relation to the Irradiated Volume Among 115 Patients Treated for Childhood Cancer

    International Nuclear Information System (INIS)

    Diallo, Ibrahima; Haddy, Nadia; Adjadj, Elisabeth; Samand, Akhtar; Quiniou, Eric; Chavaudra, Jean; Alziar, Iannis; Perret, Nathalie; Guerin, Sylvie; Lefkopoulos, Dimitri; Vathaire, Florent de

    2009-01-01

    Purpose: To provide better estimates of the frequency distribution of second malignant neoplasm (SMN) sites in relation to previous irradiated volumes, and better estimates of the doses delivered to these sites during radiotherapy (RT) of the first malignant neoplasm (FMN). Methods and Materials: The study focused on 115 patients who developed a solid SMN among a cohort of 4581 individuals. The homemade software package Dos E G was used to estimate the radiation doses delivered to SMN sites during RT of the FMN. Three-dimensional geometry was used to evaluate the distances between the irradiated volume, for RT delivered to each FMN, and the site of the subsequent SMN. Results: The spatial distribution of SMN relative to the irradiated volumes in our cohort was as follows: 12% in the central area of the irradiated volume, which corresponds to the planning target volume (PTV), 66% in the beam-bordering region (i.e., the area surrounding the PTV), and 22% in regions located more than 5 cm from the irradiated volume. At the SMN site, all dose levels ranging from almost zero to >75 Gy were represented. A peak SMN frequency of approximately 31% was identified in volumes that received <2.5 Gy. Conclusion: A greater volume of tissues receives low or intermediate doses in regions bordering the irradiated volume with modern multiple-beam RT arrangements. These results should be considered for risk-benefit evaluations of RT.

  18. Aspects of land application of sewage solids and gamma-irradiated dried sewage solids on calcareous soils

    International Nuclear Information System (INIS)

    McCaslin, B.D.; O'Connor, G.A.; Sivinski, J.S.

    1980-01-01

    One of the cheapest and generally most convenient methods of disposing of sewage sludge is by land application. The greatest risks of land application are potential contamination of the environment by heavy metals, other toxicants, and pathogens. Irradiation of sewage sludge has been shown to have little or no effect on sludge elements available to plants, and can remove the potential pathogen problem. Work at New Mexico State University has shown that, with little risk, gamma-irradiated sewage sludge can be used to great advantage for crop production, especially on highly calcareous soils low in heavy metals essential for plant growth

  19. Analytical solutions for thermal transient profile in solid target irradiated with low energy and high beam current protons

    International Nuclear Information System (INIS)

    Oliveira, Henrique B. de; Brazao, Nei G.; Sciani, Valdir

    2009-01-01

    There were obtained analytical solutions for thermal transient in solid targets, used in short half-life radioisotopes production, when irradiated with low energy and high beam current protons, in the cyclotron accelerator Cyclone 30 of the Institute for Energy and Nuclear Research (IPEN/CNEN-SP). The beam spatial profile was considered constant and the time depended heat distribution equation was resolved for a continuous particles flow entering the target. The problem was divided into two stages: a general solution was proposed which is the sum of two functions, the first one related to the thermal equilibrium situation and the second one related to a time dependent function that was determinate by the setting of the contour conditions and the initial conditions imposed by the real problem. By that one got an analytic function for a complete description of the heat transport phenomenon inside the targets. There were used both, numerical and symbolic computation methods, to obtain temperature maps and thermal gradients and the results showed an excellent agreement when compared with purely numerical models. The results were compared with obtained data from Gallium-67 and Thallium-201 irradiation routines conducted by the IPEN Cyclotrons accelerators center, showing excellent agreement. The objective of this paper is to develop solid targets irradiation systems (metals and oxides) so that one can operate with high levels of current beam, minimizing the irradiation time and maximizing the final returns. (author)

  20. Detecting the formation of products of radiolysis of tryptophan in foods rich in protein and irradiated with γ rays

    International Nuclear Information System (INIS)

    Kleeberg, K.K.; Wickern, B. van; Simat, T.J.; Steinhart, H.

    1999-01-01

    N-formyl kynurenine (NFK), OIA and the four hydroxytryptophan isomers (4-, 5-, 6- and 7-OH-TRP) were found as the major radiolysis products in γ-ray irradiated solutions containing tryptophan, in tripeptides and lysozyme. Their identification was achieved by enzymatic hydrolysis with pronase E under mild conditions (40 C, 30-60 min), applying electrochemical methods and RP-HPLC and uv fluroscence methods. Highly significant dissimilarity of results was shown for all the radiolysis products found in the specimens irradiated with 1.3 or 5 kGy and in non-irradiated samples. For release of the radiolysis products from protein-rich foods (egg white, white chicken meat, North Sea shrimps), a two-stage enzymatic hydrolytic process was developed, using proteinase K and carboxypeptidase A for egg white and chicken meat, and proteinase K and pronase E for the shrimps. The four OH-TRP isomers could be detected and quantified in all specimens. The contents varied from 0.02 to 1.97 mg/kg of proteine. Significant deviation of results between irradiated and non-irradiated specimens of egg white and chicken meat could be detected as from an applied dose of 3 kGy. In the shrimps, deviations were evident only at applied doses of 5 kGy. (orig./CB) [de

  1. Solid-phase photocatalytic degradation of polystyrene plastic with goethite modified by boron under UV-vis light irradiation

    International Nuclear Information System (INIS)

    Liu Guanglong; Zhu Duanwei; Zhou Wenbing; Liao Shuijiao; Cui Jingzhen; Wu Kang; Hamilton, David

    2010-01-01

    A novel photodegradable polyethylene-boron-goethite (PE-B-goethite) composite film was prepared by embedding the boron-doped goethite into the commercial polyethylene. The goethite catalyst was modified by boron in order to improve its photocatalytic efficiency under the ultraviolet and visible light irradiation. Solid-phase photocatalytic degradation of the PE-B-goethite composite film was carried out in an ambient air at room temperature under ultraviolet and visible light irradiation. The properties of composite films were compared with those of the pure PE films and the PE-goethite composite films through performing weight loss monitoring, scanning electron microscope (SEM) analysis, FT-IR spectroscopy and X-ray photoelectron spectroscopy (XPS). The photo-induced degradation of PE-B-goethite composite films was higher than that of the pure PE films and the PE-goethite composite films under the UV-irradiation, while there has been little change under the visible light irradiation. The weight loss of the PE-B-goethite (0.4 wt.%) composite film reached 12.6% under the UV-irradiation for 300 h. The photocatalytic degradation mechanism of the composite films was briefly discussed.

  2. Irradiation effect on leaching behavior and form of heavy metals in fly ash of municipal solid waste incinerator

    International Nuclear Information System (INIS)

    Nam, Sangchul; Namkoong, Wan

    2012-01-01

    Highlights: ► No research has been done to examine effect of electron beam irradiation on leaching behavior of heavy metals in fly ash. ► Electron beam irradiation on fly ash had significant effect on heavy metal leaching. ► Leaching potential of heavy metals in fly ash differed among metal species tested (Pb, Zn, Cu). ► Metal forms in the ash were analyzed to explain the difference. ► The difference could be explained by metal form change. - Abstract: Fly ash from a municipal solid waste incinerator (MSWI) is commonly classified as hazardous waste. High-energy electron beam irradiation systems have gained popularity recently as a clean and promising technology to remove environmental pollutants. Irradiation effects on leaching behavior and form of heavy metals in MSWI fly ash have not been investigated in any significant detail. An electron beam accelerator was used in this research. Electron beam irradiation on fly ash significantly increased the leaching potential of heavy metals from fly ash. The amount of absorbed dose and the metal species affected leaching behavior. When electron beam irradiation intensity increased gradually up to 210 kGy, concentration of Pb and Zn in the leachate increased linearly as absorbed dose increased, while that of Cu underwent no significant change. Concentration of Pb and Zn in the leachate increased up to 15.5% (10.7 mg/kg), and 35.6% (9.6 mg/kg) respectively. However, only 4.8% (0.3 mg/kg) increase was observed in the case of Cu. The results imply that irradiation has significant effect on the leaching behavior of heavy metals in fly ash, and the effect is quite different among the metal species tested in this study. A commonly used sequential extraction analysis which can classify a metal species into five forms was conducted to examine any change in metal form in the irradiated fly ash. Notable change in metal form in fly ash was observed when fly ash was irradiated. Change in Pb form was much greater than that of

  3. Criteria to average out the chemical shift anisotropy in solid-state NMR when irradiated with BABA I, BABA II, and C7 radiofrequency pulse sequences.

    Science.gov (United States)

    Stephane Mananga, Eugene

    2013-01-01

    Floquet-Magnus expansion is used to study the effect of chemical shift anisotropy in solid-state NMR of rotating solids. The chemical shift interaction is irradiated with two types of radiofrequency pulse sequences: BABA and C7. The criteria for the chemical shift anisotropy to be averaged out in each rotor period are obtained. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. On the modeling of irradiation-induced homogeneous precipitation in proton-bombarded Ni-Si solid solutions

    Science.gov (United States)

    Lam, Nghi Q.; Janghorban, K.; Ardell, A. J.

    1981-10-01

    Irradiation-induced solute redistribution leading to precipitation of coherent γ' particles in undersaturated Ni-based solid solutions containing 6 and 8 at.% Si during 400-keV proton bombardment was modeled, based on the concept of solute segregation in concentrated alloys under spatially-dependent defect production conditions. The combined effects of (i) an extremely large difference between the defect production rates in the peak-damage and mid-range regions during irradiation and (ii) a preferential coupling between the interstitial and solute fluxes generate a net transient flux of Si atoms into the mid-range region, which is much larger than the solute flux out of this location. As a result, the Si concentration exceeds the solubility limit and homogeneous precipitation of the γ' phase occurs in this particular region of the irradiated samples. The spatial, compositional and temperature dependences of irradiation-induced homogeneous precipitation derived from the present theoretical calculations are in good qualitative agreement with experimental observations

  5. Comparative carbon-13 nuclear magnetic resonance study at 67. 9 MHz on lysozyme (human and egg-white) and. cap alpha. -lactalbumin (human and bovine) in their native and denatured state

    Energy Technology Data Exchange (ETDEWEB)

    van Binst, G; Biesemans, M [Brussels Univ. (Belgium). Faculte des Sciences

    1975-01-01

    A first detailed comparison of the /sup 13/C spectra at high field of two lysozymes (human and egg-white) and two ..cap alpha..-lactalbumins (human and bovine milk) is presented. Assignments were made on most of the resonance peaks in the aliphatic and aromatic regions of the denatured proteins. The relative peak intensities clearly demonstrate the differences in the amino acid composition of the related proteins. The broadening and the complexity of the spectra of the native proteins reflect the non equivalence of the chemical groups in the folded conformation. The usefulness of /sup 13/C nmr spectroscopy in the study of the interaction between small molecules and proteins was tested on N-acteyl-glucosamine in the presence of lysozyme.

  6. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    CERN Document Server

    Romain, J P; Dayma, G; Boustie, M; Resseguier, T D; Combis, P

    2002-01-01

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm sup - sup 2. The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence <1.4 J cm sup - sup 2 , the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface.

  7. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    Energy Technology Data Exchange (ETDEWEB)

    Romain, J P [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Bonneau, F [Departement de Physique Theorique et Appliquee CEA/DAM Ile de France, BP 12, 91680 Bruyeres le Chatel (France); Dayma, G [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Boustie, M [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Resseguier, T de [Laboratoire de Combustion et de Detonique, ENSMA, BP 40109, 86961 Futuroscope-Chasseneuil (France); Combis, P [Departement de Physique Theorique et Appliquee CEA/DAM Ile de France, BP 12, 91680 Bruyeres le Chatel (France)

    2002-11-11

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm{sup -2}. The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence <1.4 J cm{sup -2}, the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface.

  8. Pressure measurements and an analytical model for laser-generated shock waves in solids at low irradiance

    International Nuclear Information System (INIS)

    Romain, J P; Bonneau, F; Dayma, G; Boustie, M; Resseguier, T de; Combis, P

    2002-01-01

    Low amplitude shock waves (from 1 to 300 bar) have been generated in gold layers deposited on a quartz substrate, by laser pulses at an incident fluence from 0.4 to 4.0 J cm -2 . The quartz was used as a pressure gauge for recording the induced shock profile. At a fluence -2 , the shock pressure does not exceed 10 bar and the shock front is followed by a tension peak typical of an absorption in solid state. An analytical model of the compression-tension process has been developed, accounting for shock pressure and shock profile evolution as a function of irradiation conditions and material properties. From this model a mechanical interpretation is given to previous observations of spalling of the irradiated target surface

  9. Radiobiologic significance of apoptosis and micronucleation in quiescent cells within solid tumors following γ-ray irradiation

    International Nuclear Information System (INIS)

    Masunaga, Shin-ichiro; Ono, Koji; Suzuki, Minoru; Kinashi, Yuko; Takagaki, Masao

    2001-01-01

    Purpose: To determine the frequency of apoptosis in quiescent (Q) cells within solid tumors following γ-ray irradiation, using four different tumor cell lines. In addition, to assess the significance of detecting apoptosis in these cell lines. Methods and Materials: C3H/He mice bearing SCC VII or FM3A tumors, Balb/c mice bearing EMT6/KU tumors, and C57BL mice bearing EL4 tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received γ-ray irradiation at a dose of 4-25 Gy while alive or after tumor clamping. Immediately after irradiation, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (=Q cells) was determined using immunofluorescence staining for BrdU. Meanwhile, 6 hours after irradiation, tumor cell suspensions obtained in the same manner were fixed. The apoptosis frequency in Q cells was also determined with immunofluorescence staining for BrdU. The MN and apoptosis frequency in total (P+Q) tumor cells were determined from the tumors that were not pretreated with BrdU. Results: In total cells, SCC VII, FM3A, and EMT6/KU cells showed reasonable relationships between MN frequency and surviving fraction (SF). However, fewer micronuclei were induced in EL4 cells than the other cell lines. In contrast, a comparatively close relationship between apoptosis frequency and SF was found in total cells of EL4 cell line. Less apoptosis was observed in the other cell lines. Quiescent tumor cells exhibited significantly lower values of MN and apoptosis frequency probably due to their large hypoxic fraction, similar to total tumor cells on clamped irradiation. Conclusion: γ-ray irradiation induced MN formation in SCC VII, FM3A, and EMT6/KU tumor cells, and the apoptosis was marked in EL4 cells compared with

  10. A wide temperature range irradiation cryostat for reasearch on solid state targets

    Energy Technology Data Exchange (ETDEWEB)

    Reeve, Scott; Dutz, Hartmut; Goertz, Stefan; Runkel, Stefan; Voge, Thomas [Physikalisches Institut, Universitaet Bonn (Germany)

    2012-07-01

    To qualitatively improve the data obtained in asymmetry measurements of scattering experiments the figure of merit (FOM) plays a major role and can reduce the data acquisition time when a certain precision in the measurement is needed. One of the defining factors for the improvement of the polarised experiment lies in the target choice and preparation, in particular the method employed to introduce the paramagnetic defects for the use of dynamic nuclear polarisation (DNP). To this end the Polarized Target Group in Bonn has developed a wide range temperature cryostat for the irradiation of potential target materials in which materials can be irradiated to varying doses at specified temperatures. The stable irradiation temperature of the materials can be controlled to within {+-}1 K over a range of 90 K

  11. A simple model for the microstructural evolution of solids under irradiation

    International Nuclear Information System (INIS)

    Valentin, P.P.; Martin, G.

    1982-01-01

    The coupled evolutions of the void and dislocation populations in crystals under high-temperature irradiation are studied by a simple heuristic theoretical approach: rate equations are used for describing both defect concentrations and microstructural variables, and the trajectories of the point representative of the microstructure in the appropriate state space are studied. Qualitatively different microstructural evolutions are found depending on the irradiation flux and temperature. Non-trivial behaviours are revealed such as: transient swelling, effect of cold work on the incubation dose for swelling, large dose divergence of evolutions which looked similar at low dose (which should result in large swelling heterogeneities) and radiation-enhanced sintering. (author)

  12. Experimental simulation of irradiation effects on thermomechanical behaviour of UO2 fuel: Impact of solid and gaseous fission products

    International Nuclear Information System (INIS)

    Balland, J.

    2007-12-01

    Predictive simulation of thermomechanical behaviour of nuclear fuel has to take into account irradiation effects. Fission Products (FP) can modify the thermomechanical behaviour of UO 2 . During this thesis, differentiation was made between fission products which create a solid solution with UO 2 and gaseous products, generating pressurized bubbles. SIMFUELS containing gadolinium oxide and pressurized argon bubbles were manufactured, respectively by conventional process and by Gas Pressure Sintering. Brittle and ductile behaviour of UO 2 was investigated, under experimental conditions representative of Pellet-Cladding Interaction (PCI), respectively with 3 points bending tests and compressive creep tests. Investigation of brittle behaviour of UO 2 showed that fracture is mainly controlled by natural defects, like porosities, acting like starting points for cracks propagation. Addition of simulates fission products increase the brittle-to-ductile transition temperature of UO 2 , up to 400-500 C regarding FP in solid solution, and up to 200 C for gaseous products. Fission products although reduce fracture stresses, by a factor between 1.5 and 4, respectively for gas bubbles and solid solutions. Decrease of fracture stress is linked to an increase of microstructural defects due the solid solution and to pressurized bubbles located at grain boundaries. Pellets were tested under compressive solicitation at high temperatures. Experimental results of creep tests are well represented by Norton laws. Creep controlling mechanisms are evidenced by microstructural analysis performed on pellets at different strains. On the basis of calculations made for fuels having the same microstructures than the SIMFUELs, a creep factor is determined. It revealed a strong hardening effect of the solid solution, due to the fact that the added elements anchor the dislocations, whereas pressurized bubbles showed a coupling between hardening and softening effects. (author)

  13. The kinetics of formation and transformation of silver atoms on solid surfaces subjected to ionizing irradiation

    International Nuclear Information System (INIS)

    Popovich, G.M.

    1988-01-01

    The paper discusses the results obtained in ESR-assisted studies of the kinetics of formation and transformation of silver atoms generated by γ-irradiation of silver-containing carriers. Three types of dependences have been established: (1) extreme; (2) saturation curves and (3) step-like. All the kinetic curves display, after a definite period of time, stable concentrations of adsorbed silver atoms per unit of the surface at a given temperature. Depending on the temperature of the experiment, the composition and nature of the carrier, the number of adsorbed silver ions, the irradiation dose and conditions of the experiment, a stable concentration of silver atoms at a given temperature may be equal to, higher or lower than the number of silver atoms measured immediately after γ-irradiation at a temperature of liquid nitrogen. A kinetic scheme is proposed to explain the obtained curves. The model suggests that the silver atoms adsorbed on the surface, as well as those formed after γ-irradiation, are bonded to the surface by various energies, which are related to heterogeneity of the carrier surface. (author)

  14. Determinations of the temperature of terminal solid solubility in dissolution and precipitation of hydrogen/deuterium in irradiated Zircaloy-4

    Energy Technology Data Exchange (ETDEWEB)

    Vizcaino, P [CNEA-CONICET, Centro Atomico Ezeiza (Argentina)

    2012-07-01

    The proposed plan is an approach to the metallurgical consequences of the high neutron fluencies (10''2''2 n/cm''2) on the hydrogen behavior in zirconium based alloys, based on the significance of the microstructural behavior of the high burn up fuel claddings during the dry storage period. The studies are focused on Zircaloy-4, concerning to two processes: Neutron irradiation damage; Hydrogen pick up. The Zircaloy-4 was taken from cooling channels of the PHWR Atucha 1. These components remained more than 10 years in service, reaching neutron fluencies up to 10''2''2 n/cm''2. In the last recent years, measurements of the hydride dissolution temperatures have shown that hydrogen solubility is affected by the neutron irradiation, increasing it respect to the unirradiated Zircaloy solubility. In addition, in this material the amorphization/dissolution of the second phase particles (SPPs) was observed, being proposed an interaction between the hydrogen atoms, the SPPs and the irradiation defects as a possible explanation of the observed behavior. For the present case, attention will be focused on the hydride precipitation process, since it is strongly related with delay hydrogen cracking initiation, a problem of direct concern for the dry storage. The goal of the present proposal is to make an approach to the source of the observed effect, applying several specific techniques as differential scanning calorimetry (DSC), high resolution x-ray diffraction and transmission electron microscopy. The objectives can be divided as follows: Determination of the temperatures of terminal solid solubility in dissolution (TTSSd) and in precipitation (TTSSp) in high fluency irradiated Zircaloy-4, reproducing the temperatures at which the Zircaloy fuel claddings remain during dry storage by an annealing program during the DSC experiments; Observations by optical and transmission electron microscopy of the hydride distribution before (as received material) and after high temperature

  15. On two possible mechanisms of metallic island remotion from solid surface at heavy multicharged ion irradiation

    International Nuclear Information System (INIS)

    Vorob'eva, I.V.; Geguzin, Ya.E.; Monastyrenko, V.E.

    1986-01-01

    Two mechanisms of energy transfer from a moving ion to a metallic island film on a solid surface are described. A particular case when the energy transfer quantity is enough to remove an island from the solid surface breaking adhesion bond is considered. One mechanism is 'shaking off', another one is a 'jumping up' mechanism. The essence of the first mechanism is that an ion bombarding the surface excites a cylindrical shock wave with a front that can 'shake off' islands from the solid surface along the ion trajectory when it reaches the surface. An island is heated in pulsed mode, and during thermal expansion it should push off the substrate, and so it jumps up. The pure case of such mechanism is observed when an ion transverses an island and transfers energy to the latter one that is defined by the quantity of ion energy losses in the island

  16. Electron-beam-irradiation-induced crystallization of amorphous solid phase change materials

    Science.gov (United States)

    Zhou, Dong; Wu, Liangcai; Wen, Lin; Ma, Liya; Zhang, Xingyao; Li, Yudong; Guo, Qi; Song, Zhitang

    2018-04-01

    The electron-beam-irradiation-induced crystallization of phase change materials in a nano sized area was studied by in situ transmission electron microscopy and selected area electron diffraction. Amorphous phase change materials changed to a polycrystalline state after being irradiated with a 200 kV electron beam for a long time. The results indicate that the crystallization temperature strongly depends on the difference in the heteronuclear bond enthalpy of the phase change materials. The selected area electron diffraction patterns reveal that Ge2Sb2Te5 is a nucleation-dominated material, when Si2Sb2Te3 and Ti0.5Sb2Te3 are growth-dominated materials.

  17. Viscosity of egg white from hens of different strains fed with commercial and natural additives Viscosidade da clara de ovo proveniente de poedeiras de diferentes espécies com aditivos comerciais e naturais

    Directory of Open Access Journals (Sweden)

    Fernanda Papa Spada

    2012-03-01

    Full Text Available Yolk color and egg white (albumen cleanliness and viscosity are important parameters by which consumers judge the quality of eggs. This study aimed to investigate changes in albumen viscosity during storage of eggs for up to 36 days from two different commercial laying hen strains (Carijo Barbada and Isa Brown fed a diet containing annatto (1.5 and 2.0% or a synthetic additive without synthetic colorants (control. Analyses of humidity, albumen height, pH, viscosity, foam formation, and stability were carried out on eggs. Carijo Barbada strain had smaller albumen, lower humidity and higher egg white viscosity than Isa Brown strain; however, with storage, viscosity lowered significantly on both strains. Initially, the addition of 2.0% of annatto or a synthetic additive increased viscosity in both strains, but with storage only the control maintained longer viscosity. Lower viscosity did not change foam density and stability.A coloração da gema, transparência e viscosidade da clara (albúmen são parâmetros importantes que os consumidores consideram na avaliação dos ovos. O objetivo do estudo foi verificar as trocas que ocorrem na armazenagem por 36 dias em relação à viscosidade da clara de ovos produzidos por poedeiras de duas diferentes linhagens (Carijo Barbada eIsa Brown , as quais receberam dietas contendo urucum (1,5 e 2,0% ou aditivo sintético. Foram realizadas as análises de umidade, altura do albúmen, pH, viscosidade, formação e estabilidade da espuma. A linhagem Carijó Barbada apresentou menor quantidade de albúmen, menor umidade e maior viscosidade que a linhagem Isa Brown, entretanto, com a estocagem, a viscosidade diminuiu significativamente para ambas as linhagens. Inicialmente, a adição de 2,0% de urucum ou aditivo sintético foi suficiente para aumentar a viscosidade em ovos obtidos de ambas as linhagens, mas com a estocagem, somente o controle manteve maior viscosidade. A baixa viscosidade não interferiu na

  18. Determination of radiation-induced hydrocarbons in processed food and complex lipid matrices. A new solid phase extraction (SPE) method for detection of irradiated components in food

    International Nuclear Information System (INIS)

    Hartmann, M.; Ammon, J.; Berg, H.

    1997-01-01

    Detection of irradiated components in processed food with complex lipid matrices can be affected by two problems. First, the processed food may contain only a small amount of the irradiated component, and the radiation-induced hydrocarbons may be diluted throughout the lipid matrix of the whole food. Second, in complex lipid matrices, the detection of prior irradiation is often disturbed by fat-associated compounds. In these cases, common solid phase extraction (SPE) Florisil clean-up alone is inadequate in the detection of prior irradiation. Subsequent SPE argentation chromatography of the Florisil eluate allows the measurement of small amounts of irradiated lipid-containing ingredients in processed food as well as the detection of prior irradiation in complex lipid matrices such as paprika and chilli. SPE argetation chromatography is the first method available for the selective enrichment of radiation-specific hydrocarbons from even complex lipid matrices, thus enabling the detection of irradiation does as low as 0.025 kGy. Furthermore, by using radiation-induced hydrocarbons in the detection of prior irradiation of paprika and chilli powder, a second independent method, the first being measurement of thermoluminescence, is available for the analysis of these matrices. Such analysis could be achieved by using this highly sensitive, cheap and easy to perform combined SPE Florisil/argentation chromatography method, without the need for sophisticated techniques like SFE-GC/MS or LC-GC/MS, so that highly sensitive detection of prior irradiation colud be performed in almost every laboratory

  19. Consideration of the 'Burp' phenomenon in solid methane accounting for nonuniform distribution of irradiation defects

    International Nuclear Information System (INIS)

    Shabalin, E. P.

    1997-09-01

    This paper focuses on an optional model of radical recombination in solid methane, apart from conventional theory. It shares the common property of two-order reactions, but accounts for local nonuniformitites of the objects involved (such as radical concentration, the track nature of energy deposition, and others). Accounting for local nonuniformity provides absolutely different results for the time dependence of the space-averaged concentration of radicals, both for the processes of their storage and 'burping', compared to the common approach; it also brings new conditions for the thermal instability of the methane slug under irradiation and gives a better understanding of most of the strange features of burp performances.

  20. Effect of solid phase on the selectivity of alkyl radical formation by gamma-irradiation of branched alkanes

    International Nuclear Information System (INIS)

    Koizumi, Hitoshi; Hashino, Masatoshi; Ichikawa, Tsuneki; Yoshida, Hiroshi

    1992-01-01

    ESR and electron spin echo measurements of alkyl radicals generated by γ-irradiation of glassy and crystalline branched alkanes C 10 ∼ C 13 have been carried out to elucidate the effect of molecular structure and solid phase on the selectivity of alkyl radical formation. Alkyl radicals generated and stabilized at 77 K in the glassy alkanes are secondary penultimate radicals. Tertiary radicals and secondary radicals other than the penultimate one are not generated either by hydrogen abstraction or from ionized or excited molecules. In the crystalline alkanes, however, a small amount of secondary internal radicals are generated in addition to the predominant formation of the secondary penultimate radicals. It is concluded that the detachment of C-H hydrogen preferentially takes place at the location where the motion of carbon atoms assisting the detachment of the C-H hydrogen easily occurs. (author)

  1. Role of ultrasonic irradiation on transesterification of palm oil using calcium oxide as a solid base catalyst

    International Nuclear Information System (INIS)

    Poosumas, Jutipong; Ngaosuwan, Kanokwan; Quitain, Armando T.; Assabumrungrat, Suttichai

    2016-01-01

    Highlights: • Transesterification of palm oil using a circulated continuous flow ultrasonic reactor. • Heterogeneous system using CaO as catalyst. • Effects of ultrasonic frequency and power, and catalyst reusability were considered. • A single high frequency and high intensity irradiation is favorable for heterogeneous system. - Abstract: Biodiesel production from transesterification of palm oil using a circulated continuous flow ultrasonic reactor was investigated. Transesterification was carried out at 60 °C, 1 atm and a methanol-to-oil molar ratio of 9:1. The highest reaction rate was achieved at the catalyst loading of 2 wt%, and biodiesel yield constantly increased until transesterification equilibrium (about 80%) was reached. A higher ultrasonic frequency (50 kHz) promoted the heterogeneously catalyzed transesterification of refined palm oil, because the three-phase system (packed solid catalyst, methanol and oil) required more spatial distribution by ultrasonic irradiation. Moreover, the highest ultrasonic power also provided highest transesterification rate and biodiesel yield due to cavitation activity enhancement. Reusability of calcium oxide catalysts was also investigated, and results showed that this can be reused to provide high biodiesel yield for at least three operations with slight decrease in the rate of reaction due to counter balance effect of organic compounds deposition on the catalyst surface. The results from this study can be a basis for scaling up of the process to industrial scale.

  2. Mono-energetic ions emission by nanosecond laser solid target irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Muoio, A., E-mail: Annamaria.Muoio@lns.infn.it [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina, Viale F.S. D’Alcontres 31, 98166 Messina (Italy); Tudisco, S. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Altana, C. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Via S. Sofia 64, 95123 Catania (Italy); Lanzalone, G. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Università degli Studi di Enna “Kore”, Via delle Olimpiadi, 94100 Enna (Italy); Mascali, D.; Cirrone, G.A.P.; Schillaci, F. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Trifirò, A. [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina, Viale F.S. D’Alcontres 31, 98166 Messina (Italy); Sezione INFN, Catania (Italy)

    2016-09-01

    An experimental campaign aiming to investigate the acceleration mechanisms through laser–matter interaction in nanosecond domain has been carried out at the LENS (Laser Energy for Nuclear Science) laboratory of INFN-LNS, Catania. Pure Al targets were irradiated by 6 ns laser pulses at different pumping energies, up to 2 J. Advanced diagnostics tools were used to characterize the plasma plume and ion production. We show the preliminary results of this experimental campaign, and especially the ones showing the production of multicharged ions having very narrow energy spreads.

  3. Tensometrical properties of volumetric crystals of germanium-silicon solid solutions irradiated by fast electrons

    International Nuclear Information System (INIS)

    Abbasov, Sh.M.

    2002-01-01

    Full Text: In the present work the tensometrical properties of Ge1-xSix solid solution monocrystal contended of up to 15 at. % Si were investigated. The radiation-proof strain gauges of researched crystals were made. For this purpose the site was cutted out from a sample, perpendicularly or in parallel of a crystal axes. After polishing the samples had thickness of 30-40 microns, and length of 2 mm

  4. Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

    International Nuclear Information System (INIS)

    McCaslin, B.D.; Sivinski, J.S.

    1979-01-01

    Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately

  5. Enzyme activity and allosteric characteristics of gamma-irradiated solid aspartate transcarbamylase

    International Nuclear Information System (INIS)

    Bigler, W.N.; Tolbert, B.M.

    1977-01-01

    Aspartate transcarbamylase purified from E. coli was lyophilized, irradiated in vacuo with γ radiation from a cesium-137 source, redissolved in buffer under a nitrogen atmosphere, and assayed for enzyme activity. Lyophilized and redissolved enzyme had normal catalytic and allosteric kinetic characteristics. The average D 37 observed with saturating substrate, 25 mM aspartate, was 4.1 Mrad. With less than saturating substrate, 5 mM aspartate, the activity increases from zero to 1.6 Mrad and then decreases with a D 37 of 7.2 Mrad. Inclusion of 1 mM CTP, an allosteric inhibitor, in the 5 mM aspartate assays results in a more pronounced maximum in the activity curve occurring at slightly higher dose, 2.2 Mrad. Inhibitability by CTP has a D 37 of 2.3 Mrad with doses below the activity maximum. Enzyme lyophilized in the presence of 1 mM CTP has a D 37 of 2.9 Mrad. ATCase activity changes caused by irradiation of lyophylized bacteria were qualitatively like the changes observed in the detailed studies with the purified enzyme. Apparent radiation sensitivities of ATCase in lyophilized bacteria were observed to vary with the technique used to disrupt the resuspended bacteria

  6. Dried gamma-irradiated sewage solids use on calcareous soils: crop yeilds and heavy metals uptake

    Energy Technology Data Exchange (ETDEWEB)

    McCaslin, B.D.; Sivinski, J.S.

    1979-01-01

    Experiments designed to examine gamma-radiation effects on extractable and plant-available sludge elements and to examine the response of crops to sludge applications on two typical, calcareous soils in New Mexico are summarized. Information has been given indicating that the radiation process of reducing pathogens in sewage products being developed by Sandia Laboratories, does not significantly increase the chemical extractability and plant uptake of a broad range of nutrients and heavy metals. However, radiation treatment greatly facilitates handling sewage for experimentation, because pathogen contamination precautions are eliminated and weed seeds killed. Studies on the effects of sludge irradiation on plant nutrient uptake revealed no concentration increases, agreeing with results presented herein. Sewage products may have special potential for use on calcareous soils, such as in New Mexico. For instance, in New Mexico the lack of potassium in sewage products is not a problem and the naturally high pH of New Mexico soil greatly reduces plant availability of many problem heavy metals. Dramatic increases in yield are typified by the greenhouse and field results presented herein, especially for the known micronutrient deficient soils of New Mexico. Results indicate that sewage sludge is an excellent Zn and Fe fertilizer. More research needs to be done before the economics of sludge application can be calculated and more field information is needed before irradiated sewage products are used indiscriminately. (ERB)

  7. Tensile properties of neutron irradiated solid HIP 316L(N). ITER Task T214, NET deliverable GB6 ECN-5

    International Nuclear Information System (INIS)

    Van Osch, E.V.; Tjoa, G.L.; Boskeljon, J.; Van Hoepen, J.

    1998-05-01

    The tensile properties of neutron irradiated Hot Isostatically Pressed (HIP) joints of type 316L(N) stainless steel (heat PM-130) have been measured. Cylindrical tensile test specimens of 4 mm diameter were irradiated in the High Flux Reactor (HFR) in Petten, The Netherlands, simulating the first wall conditions by a combination of high displacement damage with proportional amounts of helium. The solid HIP specimens were irradiated up to a target dose level of 5 dpa at a temperature of 550K. The damage levels realized range from 3.0 to 4.1 dpa, with helium contents up to 38 appm. Post irradiation testing temperatures ranged from 300 to 700K. The report contains the experimental conditions and summarises the results, which are given in terms of engineering stresses and strains and reduction of area. The main conclusions are that the unirradiated solid-HIP material is very soft, assumingly due to the relatively large grain size. Neutron irradiation induces both hardening and reduction of ductility, similar to the behaviour of 316L(N) plate. No failures related to debonding were observed for the tests of the unirradiated samples, however one of eight tested irradiated specimens fractured in the HIP joint, showing a flat fracture surface and a low reduction of area. 6 refs

  8. Investigation of a 0.52 eV absorption band of n-type Ge1-xSix solid solutions irradiated with fast electrons at 77 K

    International Nuclear Information System (INIS)

    Abbasov, Sh.M.; Allakhverdiev, K.R.; Agaverdieva, G.T.; Bakhyshov, N.A.; Nagiev, A.I.

    1987-01-01

    Solid solutions belonging to the Ge 1-x Si x system are among the promising semiconductor materials. There is no published information on the absorption band in the region of 0.52 eV in Ge 1-x Si x solid solutions irradiated with fast electrons. The authors determined the infrared absorption spectra, impurity photoconductivity, and Hall effect of n-type Ge 1-x Si x solid solutions doped with antimony. These solid solutions were irradiated at 77 K with 5 MeV electrons in doses up to 2 x 10 17 cm -2 . This irradiation was carried out by a method described in Ref. 3

  9. Solid targets and irradiation facilities for production of diagnostic and therapeutic radionuclides at the Debrecen cyclotron

    International Nuclear Information System (INIS)

    Tarkanyi, F.; Ando, L.; Szucs, Z.; Mahunka, I.; Kovacs, Z.

    2000-01-01

    The MGC-20E (NIIEFA, Leningrad, USSR) variable energy compact cyclotron (k=20) was installed in ATOMKI (Debrecen, Hungary) in 1985. Protons, deuterons, 3 He- and α-particles can be accelerated with currents up to 300 μA for internal irradiation and up to 50 μA for external beams. The establishment of the Cyclotron Laboratory was partly supported by the International Atomic Energy Agency. The application of the cyclotron is multipurpose: basic nuclear research, application of activation technique for analytical and wear studies, application of intense fast neutron source for agro-biological, bio-medical application and for radiation damage test of electronic components, and finally radioisotope production for medical diagnostics and for other scientific and applied fields. The cyclotron laboratory has six target rooms, a radiochemistry laboratory and a medical unit equipped with PET

  10. Tailor-made dimensions of diblock copolymer truncated micelles on a solid by UV irradiation.

    Science.gov (United States)

    Liou, Jiun-You; Sun, Ya-Sen

    2015-09-28

    We investigated the structural evolution of truncated micelles in ultrathin films of polystyrene-block-poly(2-vinylpyridine), PS-b-P2VP, of monolayer thickness on bare silicon substrates (SiOx/Si) upon UV irradiation in air- (UVIA) and nitrogen-rich (UVIN) environments. The structural evolution of micelles upon UV irradiation was monitored using GISAXS measurements in situ, while the surface morphology was probed using atomic force microscopy ex situ and the chemical composition using X-ray photoelectron spectroscopy (XPS). This work provides clear evidence for the interpretation of the relationship between the structural evolution and photochemical reactions in PS-b-P2VP truncated micelles upon UVIA and UVIN. Under UVIA treatment, photolysis and cross-linking reactions coexisted within the micelles; photolysis occurred mainly at the top of the micelles, whereas cross-linking occurred preferentially at the bottom. The shape and size of UVIA-treated truncated micelles were controlled predominantly by oxidative photolysis reactions, which depended on the concentration gradient of free radicals and oxygen along the micelle height. Because of an interplay between photolysis and photo-crosslinking, the scattering length densities (SLD) of PS and P2VP remained constant. In contrast, UVIN treatments enhanced the contrast in SLD between the PS shell and the P2VP core as cross-linking dominated over photolysis in the presence of nitrogen. The enhancement of the SLD contrast was due to the various degrees of cross-linking under UVIN for the PS and P2VP blocks.

  11. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion related to a notification from the International Organisation of Vine and Wine (OIV) on ovalbumin/egg white to be used in the manufacture of wine as clarification processing aids pursuant to Article 6, paragraph 11

    DEFF Research Database (Denmark)

    Tetens, Inge

    Following a request from the European Commission, the Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver a scientific opinion related to a notification from the International Organisation of Vine and Wine on ovalbumin/egg white to be used in the manufacture of wine...... following double-blind placebo controlled food challenges with wines fined with ovalbumin/egg white. This application refers to new analytical methods developed for the detection of egg allergens in the fining agent and the detection of ovalbumin in wine. There were no changes in the wine manufacturing...... process and no new clinical studies were provided. Taking into account the information provided on the characterisation of the fining agents regarding their content of egg proteins other than ovalbumin, the lack of standardisation of the wine manufacturing process, and that no new clinical data have been...

  12. Solid organic residues produced by irradiation of hydrocarbon-containing H2O and H2O/NH3 ices - Infrared spectroscopy and astronomical implications

    International Nuclear Information System (INIS)

    Khare, B.N.; Thompson, W.R.; Murray, B.G.J.P.T.; Chyba, C.F.; Sagan, C.

    1989-01-01

    Plasma-discharge irradiations were conducted for the methane clathrate expected in outer solar system satellites and cometary nuclei; also irradiated were ices prepared from other combinations of H 2 O with CH 4 , C 2 H 6 , or C 2 H 2 . Upon evaporation of the yellowish-to-tan irradiated ices, it is found that a colored solid film adheres to the walls of the reaction vessel at room temperature. These organic films are found to exhibit IR band identifiable with alkane, aldehide, alcohol, and perhaps alkene, as well as substituted aromatic functional groups. These spectra are compared with previous studies of UV- or photon-irradiated nonclathrated hydrocarbon-containing ices. 73 refs

  13. Problems of saturation of the excitation and creation of irreversible changes in solid after laser irradiation

    International Nuclear Information System (INIS)

    Sakhnyuk, L.A.; Trokhimchuck, P.P.

    2009-01-01

    The problem of modeling of processes of the irreversible interaction light and solid is discussed. This problem is connected with the processes of the saturation the excitation of respective scattering centers. The possible cascades of these processes are analyzed. The correlation between nonequilibrium and irreversible phenomena are analyzed. Two-dimensional sphalerite lattice of InSb was used for the kinetic modeling of the hierarchic processes of saturation of the excitation respective chemical bonds. The cascade characteristics of these processes were estimated for the cylindrical form of 'zone of energy scattering' of photon. The comparative analyses these results with results, which were received with the help straight method and method the spherical form of 'zone of energy scattering' of photon, is represented too. The good concordance of experimental and theoretical data was received. (authors)

  14. A Monte Carlo based development of a cavity theory for solid state detectors irradiated in electron beams

    International Nuclear Information System (INIS)

    Mobit, P.

    2002-01-01

    Recent Monte Carlo simulations have shown that the assumption in the small cavity theory (and the extension of the small cavity theory by Spencer-Attix) that the cavity does not perturb the electron fluence is seriously flawed. For depths beyond d max not only is there a significant difference between the energy spectra in the medium and in the solid cavity materials but there is also a significant difference in the number of low-energy electrons which cannot travel across the solid cavity and hence deposit their dose in it (i.e. stopper electrons whose residual range is less than the cavity thickness). The number of these low-energy electrons that are not able to travel across the solid state cavity increases with depth and effective thickness of the detector. This also invalidates the assumption in the small cavity theory that most of the dose deposited in a small cavity is delivered by crossers. Based on Monte Carlo simulations, a new cavity theory for solid state detectors irradiated in electron beams has been proposed as: D med (p)=D det (p) x s S-A med.det x gamma(p) e x S T , where D med (p) is the dose to the medium at point, p, D det (p) is the average detector dose to the same point, s S-A med.det is the Spencer-Attix mass collision stopping power ratio of the medium to the detector material, gamma(p) e is the electron fluence perturbation correction factor and S T is a stopper-to-crosser correction factor to correct for the dependence of the stopper-to-crosser ratio on depth and the effective cavity size. Monte Carlo simulations have been computed for all the terms in this equation. The new cavity theory has been tested against the Spencer-Attix cavity equation as the small cavity limiting case and also Monte Carlo simulations. The agreement between this new cavity theory and Monte Carlo simulations is within 0.3%. (author)

  15. Irradiation cryostat for LiH and LiD polarized solid targets

    International Nuclear Information System (INIS)

    Goertz, S.

    1991-01-01

    Scattering experiments with polarized nucleon targets are an important tool to understand the nuclear spin structure. Pion photoproduction experiments on polarized protrons and neutrons as well as measurements of the neutron and deuteron formfactors will be performed at ELSA. 7 LiH and 6 LiD seem to be attractive target materials for these experiments, because they offer high proton and deuteron polarisation, respectively. Expecially 6 LiD has further very important advantages compared to the common deuteron target materials as d-Butanol and ND 3 . This work describes the mechanism of DNP (Dynamic Nuclear Polarization) in LiH and LiD and gives a view on the nature of the so-called paramagnetic impurities in these materials. In order to maximize the nuclear polarization, the production of these radicals have to take place under well defined temperature conditions. Therefore the first version of an irradiation cryostat was built and tested in regard to its cooling power and temperature adjustment. (orig.)

  16. Solid-phase photocatalytic degradation of polyethylene-goethite composite film under UV-light irradiation

    International Nuclear Information System (INIS)

    Liu, G.L.; Zhu, D.W.; Liao, S.J.; Ren, L.Y.; Cui, J.Z.; Zhou, W.B.

    2009-01-01

    A novel photodegradable polyethylene-goethite (PE-goethite) composite film was prepared by embedding the goethite into the commercial polyethylene. The degradation of PE-goethite composite films was investigated under ultraviolet light irradiation. The photodegradation activity of the PE plastic was determined by monitoring its weight loss, scanning electron microscopic (SEM) analysis and FT-IR spectroscopy. The weight of PE-goethite (1 wt%) sample steadily decreased and led to the total 16% reduction in 300 h under UV-light intensity for 1 mW/cm 2 . Through SEM observation there were some cavities around the goethite powder in the composite films, but there were few changes except some surface chalking phenomenon in pure PE film. The degradation rate could be controlled by changing the concentration of goethite particles in PE plastic. The degradation of composite plastic initiated on PE-goethite interface and then extended into polymer matrix induced by the diffusion of the reactive oxygen species generated on goethite particle surface. The photocatalytic degradation mechanism of the composite films was briefly discussed.

  17. Fractionated half body irradiation for palliation of multiple symptomatic bone metastases from solid tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sekiguchi, Kenji; Hayashi, Shinya; Sunagawa, Yoshimitsu; Sougawa, Mitsuharu; Nakazawa, Masanori; Yamashita, Takashi (Japanese Foundation for Cancer Research, Tokyo (Japan). Hospital)

    1992-06-01

    This was a phase I-II nonrandomized study that explored the toxicity and response of fractionated half-body irradiation (F-HBI) in patients with multiple symptomatic osseous metastases. The patients had no premedication and received 10 Gy in 5 fractions with a dose rate of 15 cGy/min. At the Cancer Institute Hospital, 9 patients were treated by this technique (1 upper and lower F-HBI, 6 upper F-HBI, 2 lower F-HBI). All patients were female and had adenocarcinomas (8 breast and 1 lung). Adverse effects were myelosuppression, vomiting and partial alopecia. But hematologic toxicity was treated with blood transfusion or G-CSF. All toxicity was transient, and no pneumonitis nor radiation-related deaths occurred. When given as palliation, F-HBI was found to relieve pain in 80% of the patients. In 10% of the patients the pain relief was complete. The mean time to achieve pain relief in responders after F-HBI was 9 days. The pain relief was long-lasting and continued without need of reirradiation for 40% of the remaining patient's life. This treatment modality appears to be well tolerated and effective in patients with multiple symptomatic osseous metastases. The optimal indications, dose and fractionation for F-HBI should be further explored in randomized trials. (author).

  18. Production and Magnetic Field Confinement of Laser-Irradiated Solid Particle Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Haught, A. F.; Polk, D. H.; Fader, W. J. [United Aircraft Research Laboratories East Hartford, CT (United States)

    1969-01-15

    The focused high-intensity beam from a Q-spoiled laser has been used to form a high-temperature, high-density plasma from a single 10-20 micron radius solid particle of lithium hydride which is electrically suspended in a vacuum environment free of all material supports. Time-resolved charge collection measurements of the freely expanding plasma have shown that a high degree of ionization of the 10{sup 15} atoms in the lithium hydride particle can be achieved and that the plasma produced is essentially spherically symmetric in density over the full 4 {pi} solid angle. Time-of-flight studies of the plasma expansion have shown that average electron and ion energies exceeding 200 electron volts are obtained and that the plasma expansion rate, like the plasma density, is spherically symmetric. No charge separation or separation of the lithium and hydrogen ions is observed in the expanding plasma. Numerical calculations of the plasma formation and expansion have been made using a one-dimensional spherical hydrodynamic model and, on the basis of the results obtained, an integrated similarity model has been developed for calculations of the plasma time history and energy over the range of conditions employed in the experiments. These calculations, which include the effects of laser pulse time history, fraction of the incident beam occupied by the expanding plasma, radial density and velocity gradients within the plasma, and spatial distribution of the incident laser energy, give results for the plasma radial density distribution, velocity profile, and plasma energy in good agreement with those determined experimentally over the full range of the present measurements. Measurements have been carried out to examine the interaction of these laser -produced plasmas with mirror, cusp, and minimum-B magnetic fields. Experiments with mirror and minimum-B magnetic fields up to 8 kC show that plasmas with densities of 10{sup 12} -10{sup 13} cm{sup -3} are confined for times of 5

  19. Effect of combination of chitosan coating and irradiation on physicochemical and functional properties of chicken egg during room-temperature storage

    International Nuclear Information System (INIS)

    Liu Xianxe; Jang, Aera; Kim, Dong Hun; Lee, Bong Duk; Lee, Mooha; Jo, Cheorun

    2009-01-01

    The effect of combination of chitosan coating and irradiation on quality and storage stability of shell egg was investigated. Salmonella typhimurium inoculated on eggshell was not detected by irradiation of 2.0 kGy at day 0 and/or chitosan coating (1%, pH 5.0) after 3 days of storage. One-day-old fresh chicken egg was chitosan coated and irradiated at 0, 0.5, 1.0, 1.5 and 2.0 kGy by gamma ray. The egg samples were stored at room temperature for 14 days and the effects of the combination treatment on internal physicochemical and functional properties were investigated. The Haugh unit of egg was decreased by irradiation even at 0.5 kGy. Irradiation increased the lipid oxidation in egg yolk at 2 kGy but the egg with chitosan coating reduced the level of lipid oxidation. Irradiation increased the foaming ability of egg white and decreased viscosity of egg yolk and white. Results suggested that combination of irradiation and chitosan coating can improve safety of shell egg but irradiation treatment may reduce the egg quality for direct consumption. However, an improved functional property for further processing and efficient separation of egg white and yolk can be expected for egg processing industry using irradiation.

  20. Detection of irradiated food by the changes in protein molecular mass distribution

    International Nuclear Information System (INIS)

    Niciforovic, A.; Radojcic, M.; Milosavljevic, B.H.

    1998-01-01

    Complete text of publication follows. The present work deals with the radiation-induced damage of proteins, which is followed by the change in the molecular mass. The phenomenon was studied on protein rich samples, i.e., chicken meat and dehydrated egg white. The radiation dose applied was in the range of the ones used for food microbial control. Chicken drumstick and chicken white meat proteins were separated according to their molecular mass. The protein profile was compared to the meat samples irradiated in the frozen state with 5 kGy at 60 Co source. In the case of chicken white meat, irradiation produces both nonselective protein scission (e.g. the amount of proteins of molecular mass larger than 30 kDa decreases, while the amount of proteins of molecular mass smaller than 30 kDa increases), and selective protein scission (e.g. appearance of a protein fragment of molecular mass equal to 18 kDa). In the case of chicken drumstick proteins the irradiation induces both the protein scission and the aggregation. The changes are nonspecific as well as specific and the generation of Mm = 18 kDa protein fragment was observed again. Irradiation of aerated dehydrated egg white proteins produces only nonselective protein scission. The results are discussed in view of the routine application of SDS-PAGE method for the detection of irradiated foodstuff

  1. Separation of actinides from irradiated An–Zr based fuel by electrorefining on solid aluminium cathodes in molten LiCl–KCl

    Energy Technology Data Exchange (ETDEWEB)

    Souček, P., E-mail: Pavel.Soucek@ec.europa.eu [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Murakami, T. [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Claux, B.; Meier, R.; Malmbeck, R. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany); Tsukada, T. [Central Research Institute of Electric Power Industry (CRIEPI), Komae-shi, Tokyo 201-8511 (Japan); Glatz, J.-P. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Postfach 2340, 76125 Karlsruhe (Germany)

    2015-04-15

    Highlights: • Electrorefining process in molten LiCl-KCl using solid Al electrodes was demonstrated. • High separation factors of actinides over lanthanides were achieved. • Efficient recovery of actinides from irradiated nuclear fuel was achieved. • Uniform, dense and well adhered deposits were obtained and characterised. • Kinetic parameters of actinide–aluminium alloy formation were evaluated. - Abstract: An electrorefining process for metallic spent nuclear fuel treatment is being investigated in ITU. Solid aluminium cathodes are used for homogeneous recovery of all actinides within the process carried out in molten LiCl–KCl eutectic salt at a temperature of 500 °C. As the selectivity, efficiency and performance of solid Al has been already shown using un-irradiated An–Zr alloy based test fuels, the present work was focused on laboratory-scale demonstration of the process using irradiated METAPHIX-1 fuel composed of U{sub 67}–Pu{sub 19}–Zr{sub 10}–MA{sub 2}–RE{sub 2} (wt.%, MA = Np, Am, Cm, RE = Nd, Ce, Gd, Y). Different electrorefining techniques, conditions and cathode geometries were used during the experiment yielding evaluation of separation factors, kinetic parameters of actinide–aluminium alloy formation, process efficiency and macro-structure characterisation of the deposits. The results confirmed an excellent separation and very high efficiency of the electrorefining process using solid Al cathodes.

  2. Low cycle fatigue properties of neutron irradiated solid HIP 316L(N). ITER Task T214, NET deliverable GB6 ECN-5

    International Nuclear Information System (INIS)

    Rensman, J.; Van Osch, E.V.; Tjoa, G.L.; Boskeljon, J.; Van Hoepen, J.

    1998-05-01

    The Low Cycle Fatigue (LCF) properties of neutron irradiated Hot Isostatically Pressed (HIP) joints of type 316L(N) stainless steel (heat PM-130) have been measured, as well as the LCF properties of reference 316L(N)-ERHII. Cylindrical LCF test specimens of 3 mm diameter were irradiated in the High Flux Reactor (HFR) in Petten, The Netherlands, simulating the first wall conditions of future fusion reactors by a combination of high displacement damage with proportional amounts of helium. The solid HIP specimens were irradiated up to a target dose level of 5 dpa at a temperature of 550K. The damage levels realised range from 3.0 to 4.4 dpa, with helium contents up to 41 appm. Testing temperature was equal to the irradiation temperature: 550K. The report contains the experimental conditions and summarises the results, which are given in terms of first cycle stress, the peak stress, the number of cycles where the peak stress is reached, the stress at half life and the plastic strain at half life, and the total number of cycles to failure, N f . The main conclusions are that the unirradiated solid-HIP materials has the same LCF properties as unirradiated 316L(N)-ERHII plate material. The neutron irradiation induces both hardening and reduction of fatigue life. The bond does not seem to have any effect on the fatigue properties for the unirradiated solid HIP 316L(N), whereas a combined effect of irradiation and the bond cannot be established. No failures related to debonding of the joint were observed for the tests. 7 refs

  3. The binding of platinum hexahalides (Cl, Br and I) to hen egg-white lysozyme and the chemical transformation of the PtI{sub 6} octahedral complex to a PtI{sub 3} moiety bound to His15

    Energy Technology Data Exchange (ETDEWEB)

    Tanley, Simon W. M.; Starkey, Laurina-Victoria; Lamplough, Lucinda; Kaenket, Surasek; Helliwell, John R., E-mail: john.helliwell@manchester.ac.uk [University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

    2014-08-29

    The platinum hexahalides have an octahedral arrangement of six halogen atoms bound to a Pt centre, thus having an octahedral shape that could prove to be useful in interpreting poor electron-density maps. In a detailed characterization, PtI{sub 6} chemically transformed to a square-planar PtI{sub 3} complex bound to the N{sup δ} atom of His15 of HEWL was also observed, which was not observed for PtBr{sub 6} or PtCl{sub 6}. This study examines the binding and chemical stability of the platinum hexahalides K{sub 2}PtCl{sub 6}, K{sub 2}PtBr{sub 6} and K{sub 2}PtI{sub 6} when soaked into pre-grown hen egg-white lysozyme (HEWL) crystals as the protein host. Direct comparison of the iodo complex with the chloro and bromo complexes shows that the iodo complex is partly chemically transformed to a square-planar PtI{sub 3} complex bound to the N{sup δ} atom of His15, a chemical behaviour that is not exhibited by the chloro or bromo complexes. Each complex does, however, bind to HEWL in its octahedral form either at one site (PtI{sub 6}) or at two sites (PtBr{sub 6} and PtCl{sub 6}). As heavy-atom derivatives of a protein, the octahedral shape of the hexahalides could be helpful in cases of difficult-to-interpret electron-density maps as they would be recognisable ‘objects’.

  4. The influence of thermal treatment and irradiation on specific resistance of (SnSe)1-x - (PrSe)x solid solutions

    International Nuclear Information System (INIS)

    Huseynov, J.I.; Murguzov, M.I.; Ismayilov, Sh.S.; Jafarov, T.A.

    2014-01-01

    Full text: It was studied some kinetic coefficients in cluding specific resistance of (SnSe) 1 -x - (PrSe) x solid solutions as well. Special interest was caused by composetions of above mentioned system for which the influence of irradiation and thermal treatment following this irradiation was explored. By its electric characteristics praseodymium monoselenide belongs to metals because a metallic link is formed among cation atoms in PrSe, at the expense of cohich praseodymium atoms possess an oxidation degree equalling to 3+

  5. Thermal conductivities for sintered and sphere-pac Li2O and γ-LiAlO2 solid breeders with and without irradiation effects

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Tam, S.W.

    1984-07-01

    Thermal conductivities (k, k/sub eff/) have been estimated for sintered and sphere-pac Li 2 O and γ-LiAlO 2 with and without neutron irradiation effects. The estimation is based on (1) data from unirradiated UO 2 , Li 2 O, and γ-LiAlO 2 ; (2) data from irradiated dielectric insulator materials; and (3) relatively simple physical models. Comparison of model predictions with limited ex- and in-reactor data found reasonable agreement, thus lending credence for their use in design applications. The impact of thermal conductivities on tritium breeding and power generation in fusion solid-breeder blankets is briefly highlighted

  6. Dynamics and structure of self-generated magnetics fields on solids following high contrast, high intensity laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Albertazzi, B. [LULI, École Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau (France); INRS-EMT, 1650 bd L. Boulet, J3X1S2, Varennes, Québec (Canada); Graduate School of Engineering, University of Osaka, Suita, Osaka 565-087 (Japan); Chen, S. N.; Fuchs, J., E-mail: julien.fuchs@polytechnique.fr [LULI, École Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau (France); Institute of Applied Physics, 46 Ulyanov Street, 603950 Nizhny Novgorod (Russian Federation); Antici, P. [INRS-EMT, 1650 bd L. Boulet, J3X1S2, Varennes, Québec (Canada); Dept. SBAI, Universita di Roma “La Sapienza,” Via A. Scarpa 14, 00161 Rome (Italy); Böker, J.; Swantusch, M.; Willi, O. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany); Borghesi, M. [School of Mathematics and Physics, The Queen' s University, Belfast (United Kingdom); Breil, J.; Feugeas, J. L.; Nicolaï, Ph.; Tikhonchuk, V. T.; D' Humières, E. [CELIA, University of Bordeaux - CNRS - CEA, 33405 Talence (France); Dervieux, V.; Nakatsutsumi, M.; Romagnagni, L. [LULI, École Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau (France); Lancia, L. [Dept. SBAI, Universita di Roma “La Sapienza,” Via A. Scarpa 14, 00161 Rome (Italy); Shepherd, R. [LLNL, East Av., Livermore, California 94550 (United States); Sentoku, Y. [Department of Physics, University of Nevada, Reno, Nevada 89557-0058 (United States); Starodubtsev, M. [Institute of Applied Physics, 46 Ulyanov Street, 603950 Nizhny Novgorod (Russian Federation); and others

    2015-12-15

    The dynamics of self-generated magnetic B-fields produced following the interaction of a high contrast, high intensity (I > 10{sup 19 }W cm{sup −2}) laser beam with thin (3 μm thick) solid (Al or Au) targets is investigated experimentally and numerically. Two main sources drive the growth of B-fields on the target surfaces. B-fields are first driven by laser-generated hot electron currents that relax over ∼10–20 ps. Over longer timescales, the hydrodynamic expansion of the bulk of the target into vacuum also generates B-field induced by non-collinear gradients of density and temperature. The laser irradiation of the target front side strongly localizes the energy deposition at the target front, in contrast to the target rear side, which is heated by fast electrons over a much larger area. This induces an asymmetry in the hydrodynamic expansion between the front and rear target surfaces, and consequently the associated B-fields are found strongly asymmetric. The sole long-lasting (>30 ps) B-fields are the ones growing on the target front surface, where they remain of extremely high strength (∼8–10 MG). These B-fields have been recently put by us in practical use for focusing laser-accelerated protons [B. Albertazzi et al., Rev. Sci. Instrum. 86, 043502 (2015)]; here we analyze in detail their dynamics and structure.

  7. Pomegranate peels: A novel ago-residue for tannate production by gamma irradiated aspergillus versicolor under solid state fermentation

    International Nuclear Information System (INIS)

    Khalaf, M.A.; Khalaf, S.A.

    2005-01-01

    Pomegranate peels were tested as a substrate for the production of tannate and gallic acid (GA) under solid state fermentation (SSF) using Aspergillus versicolor-g3B (highly potent gamma irradiated tannate producer isolate). The fungal strain was grown on the substrate without any pre-treatment. Different parameters for maximum production of tannate by this strain under SSF method were optimized. The maximum tannate yield (12.45μg-1ds) and GA (94%) were obtained when SSF was carried out at ph 5.0, 30 degree C, 60% initial substrate moisture, 20% inoculum size, 3% tannic acid and 1% ammonium nitrate as additional carbon and nitrogen sources, after 96 h of fermentation. The crude tannate from this isolate showed ph and temperature optima of 5.0 and 50 degree C, respectively. Also, the enzyme was stable in a broad ph range of 3-8 for 24 h and was also heat stable as it retained 65% activity at 70 degree C after 1 hour

  8. Peptide Mass Fingerprinting of Egg White Proteins

    Science.gov (United States)

    Alty, Lisa T.; LaRiviere, Frederick J.

    2016-01-01

    Use of advanced mass spectrometry techniques in the undergraduate setting has burgeoned in the past decade. However, relatively few undergraduate experiments examine the proteomics tools of protein digestion, peptide accurate mass determination, and database searching, also known as peptide mass fingerprinting. In this experiment, biochemistry…

  9. Szilard-Chalmers effect in solid H I O{sub 4}. 2 H{sub 2} O by neutron irradiation (source-reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Takriti, S [radiochemistry laboratory, syrian atomic energy commission P.O. Box 6091 Damascus, (Syrian Arab Republic)

    1995-10-01

    The Szilard-Chalmers effect in solid periodic acid was investigated. In order to study the initial distribution of {sup 128I} o{sub 4} as a function of neutron flux, samples were irradiated utilizing both neutron source ({sup 241} Am-Be), the manual vertical irradiation channel and the thermal column of ET-R R-1 research reactor in Egypt. The initial retention reached a maximum of 40% after 120 minutes at 5.5 x 10 {sup 8} n s{sup -1} cm {sup -2}. The data was analysed using first order reaction. As a result, the activation Ko= 2.82 x 10 {sup 11} (S{sup -1}), respectively. Kinetics comparison of the dehydration and irradiation reactions for this solid showed disorder in the crystallographic form. Such disorder may be the result of dehydration or irradiation reactions, where the loss of water molecule will lead to formation of vacancies which, in turn, are responsible for the distribution process. 6 figs., 1 tab.

  10. Fracture toughness of neutron irradiated solid and powder HIP 316L(N). ITER Task 214, NET deliverable GB6 ECN-5

    International Nuclear Information System (INIS)

    Rensman, J.; Van den Broek, F.P.; Jong, M.; Van Osch, E.V.

    1998-04-01

    The fracture toughness properties of unirradiated and neutron irradiated type 316L(N) stainless steel plate (European Reference Heat ERHII), conventional 316L(N) solid HIP joints (heat PM-130), and 316L(N)-1G powder HIP material have been measured. Compact tension specimens with a thickness of 12 and 5 mm were irradiated in the High Flux Reactor (HFR) in Petten, The Netherlands, simulating the fusion reactor's first wall conditions by a combination of high displacement damage with proportional amounts of helium. The solid HIP (or HIP-bonded) CT-specimens were irradiated in two separate experiments: SIWAS-6 with 1.3 to 2.3 dpa (1.7 dpa av.) at 353 K, and CHARIOT-3 with 2.7 to 3.1 dpa (2.9 dpa av.) at 600 K. The plate material and powder HIP CT-specimens were irradiated in one experiment only, SIWAS-6. The helium content is up to 20 appm for the 2.9 dpa (av.) dose level. Testing temperatures of 353K and 573K have been used for the fracture toughness experiments. The report contains the experimental conditions and summarises the results, which are given in terms of J-resistance curve fits. The main conclusions are that all three materials have very high toughness in the unirradiated state with little difference between them; the solid HIP has the highest toughness, the powder HIP lowest. The toughness of all three materials is reduced significantly by irradiation, the reduction is the least for the plate material and the highest for the powder HIP material. However, many, but not all, of the solid HIP CT specimens showed debonding of the joint during testing. The machined notch of the CT specimens was not exactly on the joint interface, which could lead to unjustified interpretation of the measured values as being the toughness of the joint, the toughness of the joint being probably much lower. The reduction by irradiation of the fracture toughness of the powder HIP material is clearly larger than for plate material, which is confirmed by the observed early initiation

  11. Irradiation of liquid egg, frozen egg, powdered egg, egg yolk and white of egg: reducing the population of Salmonella enteritidis and sensory aspects and physico-chemical

    International Nuclear Information System (INIS)

    Froehlich, Angela

    2004-01-01

    Eggs and their products have been incriminated in foodborne disease outbreaks due to Salmonella enteritidis contamination. Irradiation is a food preservation technology that could be applied to minimize the problem. The aim of this study was to determine the effect of irradiation in liquid and frozen egg as well as in powdered egg, egg yolk and egg white spiked with Salmonella enteritidis. Spiked samples of liquid egg, egg white and egg yolk were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 kGy and spiked samples of frozen and powdered egg were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 3,5 e 4,0 kGy. Raw odour, cooked odour and taste of non inoculated and irradiated samples and non irradiated samples of egg and egg products were analysed by a trained penal. Viscosity and lipid oxidation (malonaldehyde concentration) were also determined. Doses of 2,0; 3,0; 3,5; 3,0 e 3,5 kGy reduced in 5 log the population of S. Enteritidis in liquid and frozen egg, powdered egg yolk, egg white and egg, respectively, with moderate alterations in relation to non irradiated samples detected by the trained penal. Viscosity and lipid oxidation in the powdered products, however, showed more intense alterations. Therefore, irradiation can be considered a feasible process for liquid and frozen egg while when applied to powdered products it should be considered the type of food product to which they will be added due to alterations in viscosity. (author)

  12. Primary and aggregate color centers in proton irradiated LiF crystals and thin films for luminescent solid state detectors

    International Nuclear Information System (INIS)

    Piccinini, M; Ambrosini, F; Ampollini, A; Bonfigli, F; Libera, S; Picardi, L; Ronsivalle, C; Vincenti, M A; Montereali, R M

    2015-01-01

    Proton beams of 3 MeV energy, produced by the injector of a linear accelerator for proton therapy, were used to irradiate at room temperature lithium fluoride crystals and polycrystalline thin films grown by thermal evaporation. The irradiation fluence range was 10 11 -10 15 protons/cm 2 . The proton irradiation induced the stable formation of primary and aggregate color centers. Their formation was investigated by optical absorption and photoluminescence spectroscopy. The F 2 and F 3 + photoluminescence intensities, carefully measured in LiF crystals and thin films, show linear behaviours up to different maximum values of the irradiation fluence, after which a quenching is observed, depending on the nature of the samples (crystals and films). The Principal Component Analysis, applied to the absorption spectra of colored crystals, allowed to clearly identify the formation of more complex aggregate defects in samples irradiated at highest fluences. (paper)

  13. Primary and aggregate color centers in proton irradiated LiF crystals and thin films for luminescent solid state detectors

    Science.gov (United States)

    Piccinini, M.; Ambrosini, F.; Ampollini, A.; Bonfigli, F.; Libera, S.; Picardi, L.; Ronsivalle, C.; Vincenti, M. A.; Montereali, R. M.

    2015-04-01

    Proton beams of 3 MeV energy, produced by the injector of a linear accelerator for proton therapy, were used to irradiate at room temperature lithium fluoride crystals and polycrystalline thin films grown by thermal evaporation. The irradiation fluence range was 1011-1015 protons/cm2. The proton irradiation induced the stable formation of primary and aggregate color centers. Their formation was investigated by optical absorption and photoluminescence spectroscopy. The F2 and F3+ photoluminescence intensities, carefully measured in LiF crystals and thin films, show linear behaviours up to different maximum values of the irradiation fluence, after which a quenching is observed, depending on the nature of the samples (crystals and films). The Principal Component Analysis, applied to the absorption spectra of colored crystals, allowed to clearly identify the formation of more complex aggregate defects in samples irradiated at highest fluences.

  14. Effect of molecular weight on radiation chemical degradation yield of chain scission of γ-irradiated chitosan in solid state and in aqueous solution

    International Nuclear Information System (INIS)

    Tahtat, Djamel; Mahlous, Mohamed; Benamer, Samah; Nacer Khodja, Assia; Larbi Youcef, Souad

    2012-01-01

    Chitosan A 1 , A 2 and A 3 with molecular weight of 471, 207 and 100 kDa respectively, produced from squid pen chitin was degraded by gamma rays in the solid state and in aqueous solution with various doses in air at ambient temperature. Effect of molecular weight on radiation chemical degradation yield of chain scission and degradation rate constants of γ-irradiated chitosan in solid state and in aqueous solution was investigated. The radiation chemical degradation yield G (s) and degradation rate values were calculated. The molecular weight changes were monitored by capillary viscometry method and the chemical structure changes were followed by UV analysis. The results showed that, the degradation of chitosan was faster in solution, than in solid state. The values of G (s) in solid state and in aqueous solution were respectively 1.1×10 −8 mol/J and 0.074×10 −7 mol/J for A 1 , 4.42×10 −8 mol/J and 0.28×10 −7 mol/J for A 2 and 6.08×10 −8 mol/J and 0.38×10 −7 mol/J for A 3 . Degradation rate constants values ranged from 0.41×10 −5 to 2.1×10 −5 kGy −1 in solid state, whereas in solution they ranged from 13×10 −5 to 68×10 −5 kGy −1 . The chitosan A 3 was more sensitive to radiolysis than A 1 and A 2 . The chain scission yield, G (s) and degradation rate constants seems to be greatly influenced by the initial molecular weight of the chitosan. Structural changes in irradiated chitosan are revealed by the apparition of absorption peaks at 261 and 295 nm, which could be attributed to the formation of carbonyl groups. In both conditions the peak intensity was higher in chitosan A 3 than in A 1 and A 2 , the oxidative products decreased with increasing molecular weight of chitosan. - Highlights: ► We investigated the effects of MW on G (s) value of γ-irradiated chitosan in solid and aqueous state. ► Chitosan with low molecular weight was more sensitive to radiolysis than high molecular weight. ► G (s) value and degradation rate

  15. Effect of neutron irradiation on etching, optical and structural properties of microscopic glass slide used as a solid state nuclear track detector

    International Nuclear Information System (INIS)

    Singh, Surinder; Kaur Sandhu, Amanpreet; Prasher, Sangeeta; Prakash Pandey, Om

    2007-01-01

    Microscopic glass slides are soda-lime glasses which are readily available and are easy to manufacture with low production cost. The application of these glasses as nuclear track detector will help us to make use of these glasses as solid-state nuclear track detector. The present paper describes the variation in the etching, optical and structural properties of the soda-lime microscopic glass slides due to neutron irradiation of different fluences. The color transformation and an increase in the optical absorption with neutron irradiation are observed. Both the bulk and track etch rates are found to increase with neutron fluence, thus showing a similar dependence on neutron fluence, but the sensitivity remains almost constant

  16. Synthesis and characterization of CdSe/ZnS core-shell quantum dots immobilized on solid substrates through laser irradiation

    International Nuclear Information System (INIS)

    Gyoergy, E.; Perez del Pino, A.; Roqueta, J.; Ballesteros, B.; Miguel, A.S.; Maycock, C.; Oliva, A.G.

    2012-01-01

    CdSe/ZnS core-shell quantum dots (QDs) have been immobilized onto solid substrates by matrix assisted pulsed laser evaporation (MAPLE). An UV KrF* (λ = 248 nm, τ FWHM ≅ 25 ns) excimer laser source was used for irradiations of the composite MAPLE targets. The targets were prepared by the dispersion of the CdSe/ZnS QDs in a solvent with high absorption at the incident laser radiation. The dependence of the surface morphology, crystalline structure, chemical composition, and functional properties of the laser transferred CdSe/ZnS QDs on the processing conditions as incident laser fluence value and ambient atmosphere inside the irradiation chamber was investigated. The possible physical mechanisms implied in the laser ablation process were identified. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Synthesis and characterization of CdSe/ZnS core-shell quantum dots immobilized on solid substrates through laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gyoergy, E. [Centre d' Investigacions en Nanociencia i Nanotecnologia, Institut Catala de Nanotecnologia, Consejo Superior de Investigaciones Cientificas (CIN2, ICN-CSIC), Bellaterra (Spain); National Institute for Lasers, Plasma and Radiation Physics, Bucharest (Romania); Perez del Pino, A. [Instituto de Ciencia de Materiales de Barcelona, Consejo Superior de Investigaciones Cientificas (ICMAB, CSIC), Bellaterra (Spain); Roqueta, J.; Ballesteros, B. [Centre d' Investigacions en Nanociencia i Nanotecnologia, Institut Catala de Nanotecnologia, Consejo Superior de Investigaciones Cientificas (CIN2, ICN-CSIC), Bellaterra (Spain); Miguel, A.S.; Maycock, C.; Oliva, A.G. [Instituto de Tecnologia Quimica e Biologica, Universidade Nova de Lisboa (ITQB-UNL), Oeiras (Portugal)

    2012-11-15

    CdSe/ZnS core-shell quantum dots (QDs) have been immobilized onto solid substrates by matrix assisted pulsed laser evaporation (MAPLE). An UV KrF* ({lambda} = 248 nm, {tau}{sub FWHM} {approx_equal} 25 ns) excimer laser source was used for irradiations of the composite MAPLE targets. The targets were prepared by the dispersion of the CdSe/ZnS QDs in a solvent with high absorption at the incident laser radiation. The dependence of the surface morphology, crystalline structure, chemical composition, and functional properties of the laser transferred CdSe/ZnS QDs on the processing conditions as incident laser fluence value and ambient atmosphere inside the irradiation chamber was investigated. The possible physical mechanisms implied in the laser ablation process were identified. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. optimization of process parameters for lovastatin production under solid-state fermentation from ground corn cobs by gamma irradiated aspergillus tamarri isolate

    International Nuclear Information System (INIS)

    Mattar, Z.A.; Khalaf, M.A.; Meleigy, S.A.

    2010-01-01

    rapid screening method is demonstrated for isolating lovastatin overproducing strains of gamma irradiated aspergillus tamarri. the screening methodology, based on the activity of lovastatin against the yeast candida albicans. among 24 gamma irradiated isolates of a. tamarri, the isolate G-8 was selected as best producer for lovastatin. solid state fermentation (SSF)was evaluated to produce lovastatin by a. tamarri G-8 isolate using ground corn cobs as substrate. monofactorial experiments were adopted to optimize the fermentation conditions. various crucial parameters such as particle size, moisture content, ph, temperature, inoculum size and incubation time were derived. corn cobs of particle size 0.4 mm having moisture level of 60 % and ph 5 gave the highest yield of lovastatin (12.4 mg/gram dry substrate) when inoculated with a. tamarri G-8 at inoculum size 10 % and 28 degree C for 8 days.

  19. Physical nature of structural and phase transformations in Cu-Al α solid solutions upon low-temperature irradiation and subsequent annealing

    Science.gov (United States)

    Petrenko, P. V.; Kulish, N. P.; Mel'nikova, N. A.; Grabovskii, Yu. E.

    2013-12-01

    Methods of X-ray diffraction analysis and measurements of residual resistivity have been used to study effects of electron irradiation in the temperature range of 250-330 K on the structural and phase state of the Cu-15 at % Al solid solution. The results obtained are explained by the presence in the Cu-Al alloys of an inhomogeneous short-range order of two types, i.e., low-temperature, α2 type; and high-temperature, γ2 type.

  20. Mitigation of solid waste and reuse of effluent from paint and varnish automotive and industrial treated by irradiation at electron beam accelerator

    International Nuclear Information System (INIS)

    Nascimento, Fernando C.; Ribeiro, Marcia A.; Duarte, Celina Lopes; Minamidani, Pedro T.; Guzella, Catia C.

    2011-01-01

    One of the most representative industrial segments is the polymeric coatings for house paint, automotive, industrial, marine, maintenance, and repainting markets. The general consumption of paint market in 2010 was 438,364 10 3 gallons of paint, in Brazil. However, when produce paints and varnishes, various kinds of solid wastes and liquid effluent are generated. The present research focus on the effluent from resins, water base paint and paint for electrophoresis, automotive industry, and general industrial coatings. The goal of this study is to use ionizing radiation to destroy the pollutants allowing the use of part of effluent as reuse water, and the rest discarded within the specified requirements. Actual industrial effluent samples were irradiated at Electron beam Accelerator applying absorbed doses of 10 kGy, 30 kGy and 50 kGy. The results, in this preliminary stage, showed a reduction of organic compounds and suspended solids. (author)

  1. Experimental Set-up for Irradiation of Solid H2 and D2 with Charged Particles of keV Energies

    DEFF Research Database (Denmark)

    Sørensen, H.

    1976-01-01

    crystal film thickness monitor. The target plate, which can be heated so that films are removable by evaporation, may be used both as a calorimeter and as a beam current collector. Methods for measurement of secondary electron emission coefficients were developed, and preliminary measurements were made...... with electrons and hydrogen ions. For electron bombardment, the secondary electron emission coefficient of solid deuterium was much smaller than one. It was shown possible to use the set-up to study beam desorption of very thin films. Furthermore the set-up could be used for measuring the energy......An experimental facility was built where films of solid deuterium (and hydrogen) may be made with known thickness and irradiated with pulsed beams of electrons (up to 3 keV) and light ions (up to 10 keV). Films are made on a target plate held at 2.5–3 K. Film growth rate is calibrated with a quartz...

  2. All-proportional solid-solution Rh–Pd–Pt alloy nanoparticles by femtosecond laser irradiation of aqueous solution with surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Md. Samiul Islam, E-mail: samiul-phy@ru.ac.bd; Nakamura, Takahiro; Sato, Shunichi [Tohoku University, Institute of Multidisciplinary Research for Advanced Materials (Japan)

    2015-06-15

    Formation of Rh–Pd–Pt solid-solution alloy nanoparticles (NPs) by femtosecond laser irradiation of aqueous solution in the presence of polyvinylpyrrolidone (PVP) or citrate as a stabilizer was studied. It was found that the addition of surfactant (PVP or citrate) significantly contributed to reduce the mean size of the particles to 3 nm for PVP and 10 nm for citrate, which was much smaller than that of the particles fabricated without any surfactants (20 nm), and improved the dispersion state as well as the colloidal stability. The solid-solution formation of the Rh–Pd–Pt alloy NPs was confirmed by the XRD results that the diffraction pattern was a single peak, which was found between the positions corresponding to each pure Rh, Pd, and Pt NPs. Moreover, all the elements were homogeneously distributed in every particle by STEM-EDS elemental mapping, strongly indicating the formation of homogeneous solid-solution alloy. Although the Rh–Pd–Pt alloy NPs fabricated with PVP was found to be Pt rich by EDS observation, the composition of NPs fabricated with citrate almost exactly preserved the feeding ratio of ions in the mixed solution. To our best knowledge, these results demonstrated for the first time, the formation of all-proportional solid-solution Rh–Pd–Pt alloy NPs with well size control.

  3. Cheese is a reliable alternative meal for solid-phase gastric emptying study.

    Science.gov (United States)

    Drubach, Laura A; Kourmouzi, Vasiliki; Fahey, Frederic H

    2010-05-01

    We evaluated the labeling stability of several alternative meals that could be used to perform solid-phase gastric emptying study. Cooked egg whites labeled with technetium-99m sulfur colloid served as a control. Packaged instant oatmeal and instant mashed potatoes were prepared by adding hot water. Cheddar cheese was melted. Peanut butter was added to bread. The different meals were mixed with technetium-99m sulfur colloid (2.2-3.7 MBq), chopped into small pieces and placed in a glass tube containing gastric juice. Four samples of each meal were analyzed after 1 and 4 h of agitation with a 3-D rotator (two samples per time point). The meal samples were washed with 2 ml of saline and filtered using a blood transfusion filter. The activity in each sample before and after filtering was assayed in a dose calibrator. The percentage of initial radioactivity remaining with the meal of admixture with gastric juice was measured and the average of the two samples was taken. The percentage of activity bound to the solid phase was 98.2+/-1.9, 95.6+/-1.1, 62.1+/-1.7, 41.8+/-0.6, and 74.5+/-3.8% at 1 h and 98.5+/-1.0, 95.8+/-2.6, 77.2+/-6.8, 55.5+/-3.4 and 40.2+/-22.1 at 4 h for egg whites, cheese, oatmeal, mashed potatoes and peanut butter respectively. For egg whites and cheese, there was no significant difference between the values at 1 and 4 h (P>0.8). Cheddar cheese provides an alternative meal for assessing solid gastric emptying in children comparable to egg whites. Oatmeal and mashed potatoes had low and variable labeling stability and are not recommended. In view of the significant proportion of pediatric patients who refuse to eat scrambled eggs or have allergy to eggs, the availability of other meal choices is essential. The versatility of cheddar cheese, which can be added to macaroni or as a topping on pizza, makes it a useful alternative to labeled eggs.

  4. In Quest of the Alanine R3 Radical: Multivariate EPR Spectral Analyses of X-Irradiated Alanine in the Solid State.

    Science.gov (United States)

    Jåstad, Eirik O; Torheim, Turid; Villeneuve, Kathleen M; Kvaal, Knut; Hole, Eli O; Sagstuen, Einar; Malinen, Eirik; Futsaether, Cecilia M

    2017-09-28

    The amino acid l-α-alanine is the most commonly used material for solid-state electron paramagnetic resonance (EPR) dosimetry, due to the formation of highly stable radicals upon irradiation, with yields proportional to the radiation dose. Two major alanine radical components designated R1 and R2 have previously been uniquely characterized from EPR and electron-nuclear double resonance (ENDOR) studies as well as from quantum chemical calculations. There is also convincing experimental evidence of a third minor radical component R3, and a tentative radical structure has been suggested, even though no well-defined spectral signature has been observed experimentally. In the present study, temperature dependent EPR spectra of X-ray irradiated polycrystalline alanine were analyzed using five multivariate methods in further attempts to understand the composite nature of the alanine dosimeter EPR spectrum. Principal component analysis (PCA), maximum likelihood common factor analysis (MLCFA), independent component analysis (ICA), self-modeling mixture analysis (SMA), and multivariate curve resolution (MCR) were used to extract pure radical spectra and their fractional contributions from the experimental EPR spectra. All methods yielded spectral estimates resembling the established R1 spectrum. Furthermore, SMA and MCR consistently predicted both the established R2 spectrum and the shape of the R3 spectrum. The predicted shape of the R3 spectrum corresponded well with the proposed tentative spectrum derived from spectrum simulations. Thus, results from two independent multivariate data analysis techniques strongly support the previous evidence that three radicals are indeed present in irradiated alanine samples.

  5. Study of gamma irradiation effects on the etching and optical properties of CR-39 solid state nuclear track detector and its application to uranium assay in soil samples

    International Nuclear Information System (INIS)

    Amol Mhatre; Kalsi, P.C.

    2011-01-01

    The gamma irradiation effects in the dose range of 2.5-43.0 Mrad on the etching and optical characteristics of CR-39 solid state nuclear track detector (SSNTD) have been studied by using etching and UV-Visible spectroscopic techniques. From the measured bulk etch rates at different temperatures, the activation energies for bulk etching at different doses have also been determined. It is seen that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. The optical band gaps of the unirradiated and the gamma -irradiated detectors determined from the UV-Visible spectra were found to decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation. The present studies can be used for the estimation of gamma dose in the range of 2.5-43.0 Mrad and can also be used for estimating track registration efficiency in the presence of gamma dose. The CR-39 detector has also been applied for the assay of uranium in some soil samples of Jammu city. (author)

  6. Deposition of radiation energy in solids as visualized by the distribution, structure and properties of alkyl radicals in γ-irradiated n-alkane single crystals

    International Nuclear Information System (INIS)

    Gillbro, T.; Lund, A.

    1976-01-01

    This paper summarizes results obtained earlier from ESR studies of γ-irradiated n-alkane single crystals. It also contains some new experimental results that serve to give a more complete picture of the deposition of radiation energy in solid alkanes. The experiments performed with solid n-alkanes have thus far provided structural data that permit the nature and even the conformation of alkyl radicals to be clearly understood. Two types of radical exist namely, one where the unpaired electron is located next to the end methyl group and one with the unpaired electron in the interior of the chain. The first type has a conformation which differs from that of the undamaged molecule. Microwave saturation data show that there is a difference in relaxation properties of these radicals which can be understood in terms of a difference in mobility. Relative yield measurements give the distribution of isomeric alkyl, the result differing from that obtained using product analysis in liquids. For protiated n-alkanes n-alkyl is lacking and the 2-alkyl concentration is higher than expected. For deuterated n-alkanes the ESR spectrum is mainly that of radicals with the unpaired electron located in the interior of the carbon chain. This isotope effect is again contrary to observations in liquid n-alkanes. The broad lines observed in protiated alkanes irradiated at 77 K and deuterated alkanes irradiated at 4.2 K are not believed to arise from strong spin-spin interactions. They are thought instead to arise from distorted crystal and radical structures relating to the damaged regions of the crystals. (Auth.)

  7. A study on irradiation damage of solid 5'-dTMP implanted by low energy N+ ion beam

    International Nuclear Information System (INIS)

    Shao Chunlin; Yu Zengliang

    1995-01-01

    The yields of inorganic phosphate and base released from 5'-dTMP irradiated by 30 keV N + ion beam were investigated. The fluence effects of these yields and the influence with 0.1 mol/L NaOH treatment on them were presented. It was shown that the alkali treatment would not only increase the yield of inorganic phosphate, but also damage and then split base released from the irradiated 5'-dTMP. When the irradiated samples were treated with 0.1 mol/L NaOH immediately, the yield of inorganic phosphate was increased by a factor of 1.7 and the concentration of base decreased to half of that in the sample's water solution. Furthermore, the yield of inorganic phosphate would increase by a factor of 2.8 after 40 min of alkali treatment. Irradiation effects of ion beam were mainly direct ones and had a higher value of G(P i ), greater than 0.44 molecule/100 eV

  8. Green synthesis of 3,4-dihydropyrimidinones using nano Fe3O4@meglumine sulfonic acid as a new efficient solid acid catalyst under microwave irradiation

    Directory of Open Access Journals (Sweden)

    Leila Moradi

    2018-01-01

    Full Text Available Design, synthesis and characterization of nano Fe3O4@meglumine sulfonic acid as a new solid acid catalyst for the simple and green one pot multicomponent synthesis of 3,4-dihydropyrimidin-2(1H-ones/thiones was studied. New solid acid catalyst was prepared through a clean and simple protocol and characterized using FTIR, VSM, TGA, SEM, elemental analysis (CHN and XRD techniques. Heterogenization of homogeneous catalyst as a green approach is a useful method for enhancing the efficiency of catalyst. Presented study was a new method for attachment of homogeneous highly soluble catalyst (meglumine sulfate to the magnetite nanoparticle surfaces for preparing a heterogeneous and effective catalyst. Obtained heterogeneous and reusable solid acid catalyst has high performance in the synthesis of Biginelli compounds. The reaction was performed under microwave irradiation as a rapid and green condition. Easy work up as well as excellent yield (90–98% of products in short reaction times (40–200 s and reusable catalyst are the main advantages of presented procedure. Reaction products were characterized in details using physical and chemical techniques such as melting point, 1H NMR, 13C NMR and FTIR.

  9. The influence of ICRF-159 and levamisole on the incidence of metastases following local irradiation of a solid tumor

    Energy Technology Data Exchange (ETDEWEB)

    Baker, D.; Constable, W.; Elkon, D.; Rinehart, L.

    1981-11-15

    Courses of irradiation consisting of 6000 rad in ten equal fractions over 12 days delivered to KHT sarcomas in mice controlled 55% of the local tumors but 83% of the mice died from metastases. Three strategies to reduce the risk of metastatic spread were tested. The fractionation scheme was changed to deliver the same total dose using a large initial fraction followed by seven equal portions with the same overall time. ICRF-159 was used with the intention of partially synchronizing the tumor growth fraction in a radiosensitive state of the growth cycle and of promoting normalization of the tumor vasculature. Levamisole was used to stimulate the immune system. The combination of ICRF-159 with the eight-fraction radiation course proved to be effective for both increasing local control and decreasing the incidence of metastases. The addition of levamisole did not improve the results obtained with a combination of ICRF-159 and irradiation.

  10. Influence of ICRF-159 and levamisole on the incidence of metastases following local irradiation of a solid tumor

    Energy Technology Data Exchange (ETDEWEB)

    Baker, D.; Constable, W.; Elkon, D.; Rinehart, L.

    1981-11-15

    Courses of irradiation consisting of 6000 rad in ten equal fractions over 12 days delivered to KHT sarcomas in mice controlled 55% of the local tumors but 83% of the mice died from metastases. Three strategies to reduce the risk of metastatic spread were tested. The fractionation scheme was changed to deliver the same total dose using a large initial fraction followed by seven equal portions with the same overall time. ICRF-159 was used with the intention of partially synchronizing the tumor growth fraction in a radiosensitive state of the growth cycle and of promoting normalization of the tumor vasculature. Levamisole was used to stimulate the immune system. The combination of ICRF-159 with the eight-fraction radiation course proved to be effective for both increasing local control and decreasing the incidence of metastases. The addition of levamisole did not improve the results obtained with a combination of ICRF-159 and irradiation.

  11. In situ characterization of thermal conductivities of irradiated solids by using ion beam heating and infrared imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mondrik, Nicholas; Gigax, Jonathan; Wang, Xuemei; Price, Lloyd [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Wei, Chaochen [Materials Science and Engineering Department, Texas A and M University, College Station, TX 77843 (United States); Shao, Lin, E-mail: lshao@tamu.edu [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Materials Science and Engineering Department, Texas A and M University, College Station, TX 77843 (United States)

    2014-08-01

    We propose a method to characterize thermal properties of ion irradiated materials. This method uses an ion beam as a heating source to create a hot spot on sample surface. Infrared imaging is used as a surface temperature mapping tool to record hot zone spreading. Since ion energy, ion flux, and ion penetration depth can be precisely controlled, the beam heating data is highly reliable and repeatable. Using a high speed infrared camera to capture lateral spreading of the hot zone, thermal diffusivity can be readily extracted. The proposed method has advantages in studying radiation induced thermal property changes, for which radiation damage can be introduced by using an irradiating beam over a relatively large beam spot and beam heating can be introduced by using a focused testing beam over a relatively small beam spot. These two beams can be switched without breaking vacuum. Thus thermal conductivity changes can be characterized in situ with ion irradiation. The feasibility of the technique is demonstrated on a single crystal quartz substrate.

  12. In situ characterization of thermal conductivities of irradiated solids by using ion beam heating and infrared imaging

    International Nuclear Information System (INIS)

    Mondrik, Nicholas; Gigax, Jonathan; Wang, Xuemei; Price, Lloyd; Wei, Chaochen; Shao, Lin

    2014-01-01

    We propose a method to characterize thermal properties of ion irradiated materials. This method uses an ion beam as a heating source to create a hot spot on sample surface. Infrared imaging is used as a surface temperature mapping tool to record hot zone spreading. Since ion energy, ion flux, and ion penetration depth can be precisely controlled, the beam heating data is highly reliable and repeatable. Using a high speed infrared camera to capture lateral spreading of the hot zone, thermal diffusivity can be readily extracted. The proposed method has advantages in studying radiation induced thermal property changes, for which radiation damage can be introduced by using an irradiating beam over a relatively large beam spot and beam heating can be introduced by using a focused testing beam over a relatively small beam spot. These two beams can be switched without breaking vacuum. Thus thermal conductivity changes can be characterized in situ with ion irradiation. The feasibility of the technique is demonstrated on a single crystal quartz substrate

  13. Effect of gamma-ray and electron irradiation on the response of solid-state track detectors

    International Nuclear Information System (INIS)

    Fukuda, Kyue

    1980-01-01

    Specimens of muscovite mica were first exposed to fission fragments and then to various gamma-ray fields from a 60 Co source ranging from 1.9 x 10 3 to 1.6 x 10 4 Mrad dose. The results show that the average etched width of fission-fragment tracks decreases with increasing gamma-ray dose. Shallow pits were observed in etched specimens when the gamma-ray dose exceeded 5 x 10 3 Mrad. Numerous shallow etch pits caused by the gamma-ray irradiation interfered with the observation of fission tracks in the specimens. No shallow etch pits were observed in the specimen annealed for 100 min at 600 0 C before the gamma-ray irradiation. Pre-annealing extends the ''safety limits'' of gamma background below which muscovite mica can be used to observe fission tracks without any gamma-ray interference. Gamma-ray and electron irradiation caused significant increase of the resistance to thermal decomposition of muscovite mica. The resistance increased markedly in the dose range from 5 x 10 3 to 8 x 10 3 Mrad. These phenomena suggest the use of mica to assess radiation doses of gamma rays and electrons up to several thousand megarads. (author)

  14. Quinary wurtzite Zn-Ga-Ge-N-O solid solutions and their photocatalytic properties under visible light irradiation

    Science.gov (United States)

    Xie, Yinghao; Wu, Fangfang; Sun, Xiaoqin; Chen, Hongmei; Lv, Meilin; Ni, Shuang; Liu, Gang; Xu, Xiaoxiang

    2016-01-01

    Wurtzite solid solutions between GaN and ZnO highlight an intriguing paradigm for water splitting into hydrogen and oxygen using solar energy. However, large composition discrepancy often occurs inside the compound owing to the volatile nature of Zn, thereby prescribing rigorous terms on synthetic conditions. Here we demonstrate the merits of constituting quinary Zn-Ga-Ge-N-O solid solutions by introducing Ge into the wurtzite framework. The presence of Ge not only mitigates the vaporization of Zn but also strongly promotes particle crystallization. Synthetic details for these quinary compounds were systematically explored and their photocatalytic properties were thoroughly investigated. Proper starting molar ratios of Zn/Ga/Ge are of primary importance for single phase formation, high particle crystallinity and good photocatalytic performance. Efficient photocatalytic hydrogen and oxygen production from water were achieved for these quinary solid solutions which is strongly correlated with Ge content in the structure. Apparent quantum efficiency for optimized sample approaches 1.01% for hydrogen production and 1.14% for oxygen production. Theoretical calculation reveals the critical role of Zn for the band gap reduction in these solid solutions and their superior photocatalytic acitivity can be understood by the preservation of Zn in the structure as well as a good crystallinity after introducing Ge.

  15. Highly efficient F-19 heteronuclear decoupling in solid-state NMR spectroscopy using supercycled refocused-CW irradiation

    DEFF Research Database (Denmark)

    Equbal, Asif; Basse, Kristoffer; Nielsen, Niels Christian

    2016-01-01

    We present heteronuclear F-19 refocused CW (rCW) decoupling pulse sequences for solid-state magic-angle- spinning NMR applications. The decoupling sequences have been designed specifically to ensure suppression of the pertinent C-13-F-19 dipolar coupling interactions while simultaneously suppress...

  16. Irradiation of liquid egg, frozen egg, powdered egg, egg yolk and white of egg: reducing the population of Salmonella enteritidis and sensory aspects and physico-chemical;Irradiacao de ovo liquido, congelado e ovo, gema e clara em po: reducao da populacao de Salmonella enteritidis e aspectos sensoriais e fisico-quimicos

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, Angela

    2004-07-01

    Eggs and their products have been incriminated in foodborne disease outbreaks due to Salmonella enteritidis contamination. Irradiation is a food preservation technology that could be applied to minimize the problem. The aim of this study was to determine the effect of irradiation in liquid and frozen egg as well as in powdered egg, egg yolk and egg white spiked with Salmonella enteritidis. Spiked samples of liquid egg, egg white and egg yolk were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0 kGy and spiked samples of frozen and powdered egg were exposed to 0,5; 1,0; 1,5; 2,0; 2,5; 3,0; 3,5 e 4,0 kGy. Raw odour, cooked odour and taste of non inoculated and irradiated samples and non irradiated samples of egg and egg products were analysed by a trained penal. Viscosity and lipid oxidation (malonaldehyde concentration) were also determined. Doses of 2,0; 3,0; 3,5; 3,0 e 3,5 kGy reduced in 5 log the population of S. Enteritidis in liquid and frozen egg, powdered egg yolk, egg white and egg, respectively, with moderate alterations in relation to non irradiated samples detected by the trained penal. Viscosity and lipid oxidation in the powdered products, however, showed more intense alterations. Therefore, irradiation can be considered a feasible process for liquid and frozen egg while when applied to powdered products it should be considered the type of food product to which they will be added due to alterations in viscosity. (author)

  17. Catalysis under Irradiation in the Presence of Non-Metallic Solids; Catalyse sous irradiation en presence de solides non metalliques; Radiatsionnyj kataliz pri nalichii'nemetallicheskikh tverdykh tel; Radiocatalisis en presencia de solidos no metalicos

    Energy Technology Data Exchange (ETDEWEB)

    Coekelbergs, R.; Crucq, A.; Decot, J.; Degols, L.; Frennet, A.; Lienard, G.; Timmerman, L. [Laboratoire de Chimie Nucleaire, Institut Interuniversitaire des Sciences Nucleaires et Ecole Royale Militaire, Bruxelles (Belgium)

    1963-11-15

    Catalytic processes induced by radiation in the presence of non-metallic solids are discussed, attention being given exclusively to the effects associated with modification of the steady state concentration of charge carriers. The effect of such modification on the kinetics and equilibrium of heterogeneous reactions is quantitatively estimated within the framework of the electronic theory of catalysis, due regard being paid to the electronic characteristics of the surface of the solid. In conclusion, the relationship between these phenomena, catalyst activation and transfer of energy, as previously described, is discussed. (author) [French] Les auteurs discutent des processus catalytiques induits par les radiations en presence de solides non metalliques. Ils considerent exclusivement les effets lies a la modification de la concentration stationnaire des porteurs de charge.- L'influence de cette modification sur la cinetique et l'equilibre des reactions heterogenes est evaluee quantitativement dans le cadre de la theorie electronique de la catalyse et en tenant compte de caracteristiques electroniques de la surface du solide. Enfin, ils discutent la relation existant entre ces phenomenes, l'activation des catalyseurs et le transfert d'energie decrits anterieurement. (author) [Spanish] Los autores examinan los procesos cataliticos inducidos por las radiaciones en presencia de solidos no metalicos. Consideran exclusivamente los efectos vinculados con la modificacion de la concentracion estacionaria de los portadores de carga. Sobre la base de la teoria electronica de la catalisis y teniendo en cuenta las caracteristicas electronicas de la superficie del solido, determinan cuantitativamente la influencia de aquella modificacion sobre la cinetica y el equilibrio de las reacciones heterogeneas. Por ultimo, analizan la relacion que existe entre estos fenomenos, la activacion de los catalizadores y la transmision de energia descritas anteriormente. (author) [Russian

  18. Leaching behavior of gamma-emitting fission products and Np from neutron-irradiated UO_2-ZrO_2 solid solutions in non-filtered surface seawater

    International Nuclear Information System (INIS)

    Sasaki, Takayuki; Takeno, Yuu; Kobayashi, Taishi; Kirishima, Akira; Sato, Nobuaki

    2016-01-01

    The gamma ray radionuclides Cs-137, Ba-140, I-131, Ce-141, Ru-103, Zr-95, and Np-239 were produced by neutron irradiation of UO_2-ZrO_2 solid solutions that were synthesized as simulated fuel debris under reducing and oxidizing conditions. The leaching ratio of radionuclides was investigated under atmospheric conditions at 25°C for non-filtered natural surface seawater, as well as deionized water after filtration with a membrane of 0.45-μm pore size or that of nominal molecular weight limit of 3 kDa. The uranium molar concentration was affected by the oxidation state in the solid solution samples. The congruent dissolution of Cs, I, and Ba with the hexavalent uranium of U_3O_8 was facilitated in the seawater samples, whereas a lower leaching ratio of nuclides was observed in the deionized water samples. Neptunium-239, originally produced from uranium-238 in U_3O_8, showed behavior that was similar to that of Cs, I, and Ba. However, the dissolution of Np (as a parent nuclide of Pu-239) in the debris of UO_2 and UO_2-ZrO_2 was suppressed in the same manner as Zr(IV) and Ce(IV). The concentration exhibited no filtration dependence after 15 d, which shows that most of the leached nuclides can exist in their ionic form in seawater. (author)

  19. Wheat bran as a substrate for thermo stable alpha-amylase production by gamma irradiated bacillus megaterium in solid state fermentation

    International Nuclear Information System (INIS)

    ElVatal, A.I.; Khalaf, M.A.

    2003-01-01

    Thermo stable alpha-amylase (EC 3.2.1.1) production from cheap agriculture-industrial waste wheat bran (WB) medium by superior potent gamma irradiated locally isolated strain of Bacillus megaterium in solid state fermentation (SSF) was studied. A highly yielding, stable enhanced isolated strain of bacillus megaterium in solid state fermentation (SSF) was studied. A highly yielding stable enhanced isolate B. megaterium- gamma 21F derived from the 10 kGy, treatment, exhibited the highest alpha-amylase activity under SSF, with 2.8 fold more enzyme titer as compared to the unirradiated wild strain. A vancomycin (Vm) resistant gamma irradiated enhanced isolate B. megaterium-gamma 21F2 (which was selected throughout the subsequent work) secreted (1.27 and 3.58) folds superior titers of alpha-amylase than the gamma irradiated parent isolate (B.megaterium -gamma21F) and unirradiated wild strain, respectively under SSF process. The effects of various parameters, such as moistening agent, initial moisture content level, initial ph, incubation temperature, inoculum size and incubation time on thermo stable alpha-amylase production by B.megaterium-gamma 21F2 under SSF were studied. Maximum enzyme production was recorded in WB medium moistened with (1:2, w/v) distilled water at initial ph (7.0) and inoculated with (2.24 x 10 8 cells/g WB) after 48 h incubation at 40 C degree. Between different solvents used for enzyme extraction from fermented WB mass, distilled water at ph (7.0) was the superior efficient leaching solvent. The specific activity of the precipitated partially purified crude thermo stable enzyme was (258.7 U/mg protein) with ph optima (6.5-7.0), at optimal temperatures (65-70 c degree) and it retained about 53% of its maximum activity after 12 h incubation at 70 c degree. The partially purified crude enzyme was used for starch digestion (5%0 under optimized reaction conditions, wherein (98.2%) starch hydrolysis was attained after 6 h

  20. Discussion of the origin of secondary photon and secondary ion emission during energetic particle irradiation of solids. I. The collision cascade

    International Nuclear Information System (INIS)

    Wright, R.B.; Gruen, D.M.

    1980-01-01

    Secondary photon and secondary ion emission during energetic particle irradiation of solid surfaces is assumed to arise due to excitation and de-excitation of sputtered particles originating from a collision cascade induced by the incident projectile. The excitation is postulated to occur by two alternative mechanisms: path (a), where excitation occurs at or very near the surface of the solid due to atom--atom or atom--electron collisions; and path (b), where excitation occurs as the sputtered particle leaves the solid, but is still under its influence so that electron exchange processes are permitted. Once the excited and/or ionized sputtered particle is formed nonradiative de-excitation processes are then included in the discussion which allow the excited and/or ionized particle to be de-excited and/or neutralized. The result of these nonradiative de-excitation processes is shown to provide a possible channel for the formation of new excited ''daughters'' by the de-excitation of the initial excited ''parent''. Depending on the initial excitation probability of the parent the new excited daughters are shown to contribute to various energy regions of the excited and/or ionized secondary particle energy distribution. A mathematical formalism is developed based on the neutral sputtered atom energy and velocity distributions assuming a collision cascade origin for these sputtered particles. By including various models for the excitation probability, and the survival probability for excited particles once formed to not undergo nonradiative de-excitation the resulting energy and velocity distributions of the sputtered excited and/or ionized secondary particles are calculated. These distributions are found to be a function of the emission angle depending on the model assumed for the initial excitation. From this formalism the total excited secondary particle yield may be calculated

  1. Repetitive Solid Spherical Pellet Injection and Irradiation toward the Repetitive-mode Fast-Ignition Fusion miniReactor CANDY

    International Nuclear Information System (INIS)

    HANAYAMA, Ryohei; KOMEDA, Osamu; NISHIMURA, Yasuhiko; MORI, Yoshitaka; ISHII, Katsuhiro; NAKAYAMA, Suisei; OKIHARA, Shinichiro; FUJITA, Kazuhisa; SEKINE, Takashi; SATO, Nakahiro; KAWASHIMA, Toshiyuki; KAN, Hirofumi; KURITA, Takashi; NAKAMURA, Naoki; KONDO, Takuya; FUJINE, Manabu; AZUMA, Hirozumi; HIOKI, Tatsumi; KAKENO, Mitsutaka; MOTOHIRO, Tomoyoshi

    2016-01-01

    Pellet injection and repetitive laser illumination are key technologies for realizing inertial fusion energy [1-4]. Neutron generator using lasers also requires a repeating pellet target supplier. Here we present the first demonstration of target injection and neutron generation[5]. We injected more than 1300 spherical deuterated polystyrene(C 8 D 8 ) bead pellet targets during 23 minutes at 1 Hz(Fig. 1). After the pellet targets fell for a distance of 18 cm, we applied the synchronized laser-diode-pumped ultra-intense laser HAMA. The laser intensity at the focal point is 5 x 10 18 W/cm 2 , which is high enough to generate neutrons. As a result of the irradiation, we produced 2.45-MeV DD neutrons. Figure 2 shows the neutron time-of-flight signals detected by plastic scintillators coupled to photomultipliers. The neutron energy was calculated by the time-of-flight method. The maximum neutron yield was 9.5 x 10 4 /4π sr. The result is a step toward fusion power and also suggests possible industrial neutron sources. (paper)

  2. Effect of time between x-irradiation and chemotherapy on the growth of three solid mouse tumors. V. Bleomycin

    International Nuclear Information System (INIS)

    Twentyman, P.R.; Kallman, R.F.; Brown, J.M.

    1979-01-01

    Experiments have been carried out to determine the effect of different time intervals between the administration of x-radiation (1200 rad) and bleomycin (20 mg/kg) on the growth delay produced in three mouse tumors. The tumors used were the EMT6 tumor in BALB/c mice and the KHT and RIF-1 sarcomas in C3H mice. All tumors were grown intramuscularly in the gastrocnemius muscle and treatment was carried out at a mean tumor weight of 450 mg. Time to reach 2X (for KHT) or 4X (for EMT6 and RIF-1) treatment volume was used as the endpoint of response. The drug was administered by the intraperitoneal route either 24, 6, or 2 hr before radiation, immediately before the start of radiation, or 3, 6, or 24 hr after radiation. All irradiations were carried out in unanesthetized mice. For a single administration at this dose level, bleomycin alone did not produce a significant growth delay in any of the tumors. In the RIF-1 tumor, growth delays following combination treatments were equal to the addition of the single agent growth delays. In two experiments with EMT6, contrary results were obtained, one producing longer delays following combination treatments than predicted and the other producing shorter delays. This is apparently due to the variability in the growth delay after treatment with radiation alone for this tumor. For the KHT tumor, only small differences from the addition of single agent delays were seen

  3. Growth Conditions and Gamma-Irradiation as Enhancers of Cellulase Production by Bacillus subtilis Using Solid State Fermentation of Banana Wastes

    International Nuclear Information System (INIS)

    EI Shafey, H.M.

    2008-01-01

    In the present investigation trials have been carried out to study the effect of growth conditions and y-irradiation on the enhancement of cellulases using banana wastes. Bacterial strains were isolated from degraded banana wastes. Using the plate screening medium, a hypercelIulolytic isolate was selected on the basis of the diameter of the hydrolysis zone surrounding the colonies, and identified as Bacillus subtilis. Three method of pretreatment or the substrate were applied and compared in order to increase the susceptibility of the substrate to biodegradation. The methods used were autoclaving at 121 degree C for 60 min, acid hydrolysis using 2 N HCI, and alkali hydrolysis using 2 M NaOH. Pretreatment of the substrate (banana wastes) by autoclaving at 121 degree C for 60 minutes yielded the highest carboxymethyl cellulase (CMCase) and filter paper cellulase (FPase) enzyme activities in comparing with other methods. Production of CMCase and FPase was followed during changes of the growth conditions using solid state fermentation. Results showed that the two enzymes share the same growth factors for the maximum enzymatic production including 36 degree C incubation temperature, 72 hours incubation period, 60% moisture content, 20% v/w inoculum size, and initial ph 7.0. A gamma irradiation dose of 1.5 kGy was found to have an enhancing effect on the two enzymes production. Production of FPase enzyme was enhanced by 3.43 and 2.28% in pseudo stems and leaves, respectively. On the other hand, production of CMCase enzyme was slightly enhanced by 0.91 and 0.72% using pseudo stems and leaves respectively. Results also showed that banana leaves yielded higher CMCase and FPase enzymes than pseudo stems

  4. Two-dimensional molybdenum disulphide nanoflakes synthesized by liquid-solid phase reaction method: regenerative photocatalytic performance under UV-visible light irradiation by advance oxidation process

    Science.gov (United States)

    Afsar, M. F.; Rafiq, M. A.; Siddique, Fizza; Saira, F.; Chaudhary, M. M.; Hasan, M. M.; Tok, A. I. Y.

    2018-05-01

    Molybdenum disulphide (MoS2) nanoflakes were prepared through liquid-solid phase reaction technique. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM) analysis revealed the formation of pure, polycrystalline, hexagonal phase of MoS2 nanoflakes. The texture coefficient (T{c}hkl) analysis showed that (100) plane was preferentially oriented. The specific surface area of the nanoflakes was 21 m2 g‑1 as determined using Brunaure-Emmett-Teller (BET) technique. A band gap of ∼2.05 eV for MoS2 nanoflakes was estimated from UV-visible spectrum. Regenerative photocatalytic activity of MoS2 nanoflakes was assessed by degrading methylene blue (MB) and safranin-o (SO) dyes under UV-visible light irradiation. Under light irradiation, degradation efficiency for MB was ∼99.58% in 100 min while for SO it was ∼99.89% in 70 min. The MoS2 nanoflakes exhibited excellent photocatalytic performance and good stability in a wide pH range (3–11). MoS2 nanoflakes showed a high reaction rate constant (k app ) for SO ∼ 0.104 49 min‑1 and MB ∼ 0.092 18 min‑1 as compared to other MoS2 nanostructures. The obtained exceptional photocatalytic performance of MoS2 nanoflakes offers potential applications for the treatment of polluted water as well as in other correlated fields.

  5. INFRARED AND ULTRAVIOLET SPECTRA OF METHANE DILUTED IN SOLID NITROGEN AND IRRADIATED WITH ELECTRONS DURING DEPOSITION AT VARIOUS TEMPERATURES

    International Nuclear Information System (INIS)

    Chin, Chih-Hao; Chen, Sian-Cong; Liu, Meng-Chen; Huang, Tzu-Ping; Wu, Yu-Jong

    2016-01-01

    We recorded the infrared and ultraviolet absorption spectra of CH 4 :N 2 matrix samples that underwent electron bombardment during deposition in the temperature range of 10–44 K. In contrast to a previous experiment on the IR spectroscopy of electron-bombarded icy samples, methyl and azide radicals became the main products upon electron bombardment during deposition; furthermore, reduced production of nitrile species was observed for deposition at 10 and 20 K. On the other hand, for deposition above 33 K, the observed bands of the radical species (such as methyl and azide) decreased, and bands of large nitriles appeared. This observation may suggest that radical species easily diffuse and recombine to form more complex molecules in solid nitrogen at higher temperatures. Further measurements of similar samples at 10–33 K in the UV region revealed the intense band of azide radicals at 272.5 nm and weak, broad, overlapping features of methyl and azide radicals in the 225–197 nm region. For deposition at 44 K, only a broad feature centered at 219.4 nm was observed, and the possible carriers of nitrile species were proposed based on the corresponding IR spectrum and theoretical predictions of excitation energy. This band is similar to the observed absorption feature of Pluto’s surface recorded by the Hubble telescope in terms of both band position and bandwidth. Our findings therefore further support the suggestion that complex nitrile species may exist on the surface of Pluto.

  6. Synthesis and photocatalytic degradation study of methylene blue dye under visible light irradiation by Fe1-xBixVO4 solid solutions (0 ≤ x ≤ 1.0)

    Science.gov (United States)

    Bera, Ganesh; Reddy, V. R.; Mal, Priyanath; Das, Pradip; Turpu, G. R.

    2018-05-01

    The novel hetero-structures Fe1-xBixVO4 solid solutions (0 ≤ x ≤ 1.0) with the two dissimilar end member of FeVO4 - BiVO4, were successfully synthesized by the standard solid state reaction method. The structural and chemical properties of as prepared photo-catalyst samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and UV-visible absorption spectroscopy techniques. It is confirmed from the results of XRD, Raman and FT-IR that FeVO4 and BiVO4 are in triclinic (space group P-1 (2)) and monoclinic (space group I2/b (15)) phases respectively. The Bi incorporation into Fe site of FeVO4 emerges as hetero-structures of both the end members of the solid solutions. In addition, the photocatalytic activity in the degradation of methylene blue (MB) dye under visible light irradiation was carried out through UV-visible spectroscopy measurement of photo-catalysts FeVO4, BiVO4 and mixed phases of both photo-catalyst. The results indicate that under visible light irradiation the photocatalytic activity of mixed phases were very effective and higher than the both single phases of the solid solutions. The composition x= 0.25 exhibits an excellent photocatalytic property for the degradation of MB solution under visible light irradiation rather than other.

  7. Identification of irradiated pasteurized egg products: a combined method to use in routine control

    International Nuclear Information System (INIS)

    Helle, N.; Schulzki, G.; Linke, B.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A.; Grabowski, H.U. v.; Pfordt, J.; Mauermann, U.; Juelicher, S.; Bischoff, C.; Vater, N.; Heitmann, M.

    1993-01-01

    Pasteurized egg products (whole egg, egg yolk and egg white) were tested for irradiation treatment in the German food control laboratories in Oldenburg/Niedersachsen and Kassel/Hessen as well as in the food irradiation laboratory of the German federal health office. Gas chromatographic/mass spectrometric measurements on the fat components of egg-products showed clearly whether the product had been irradiated or not. While in unirradiated samples no traces of special hydrocarbons (according to the fatty acid composition of egg) and no traces of the irradiation-specific compound 2-Dodecyl-cyclobutanone were found, irradiated control samples as well as products of two belgian suppliers contained these substances. Additionally, regarding the rather high time consumption of gas chromatography, electron spin resonance (ESR)-measurements were carried out on the packaging material of egg products. Irradiated packaging material (cellulose) could be easily detected by the appearance of a signal pair in the ESR spectrum (cellulose radical). ESR measurements are very fast and easy to perform so that this method can be used for screening. Microbiological investigations showed remarkably reduced total numbers of microorganisms for some irradiated samples, but the microbiological status is influenced by other factors like storage-time and -temperature, so that microbiological tests can not be used successfully for screening on irradiation treatment [de

  8. Study of a solid state micro-dosemeter based on a monolithic silicon telescope: Irradiations with low-energy neutrons and direct comparison with a cylindrical TEPC

    International Nuclear Information System (INIS)

    Agosteo, S.; Colautti, P.; Fanton, I.; Fazzi, A.; Introini, M. V.; Moro, D.; Pola, A.; Varoli, V.

    2011-01-01

    A silicon device based on the monolithic silicon telescope technology coupled to a tissue-equivalent converter was proposed and investigated for solid state microdosimetry. The detector is constituted by a DE stage about 2 μm in thickness geometrically segmented in a matrix of micrometric diodes and a residual-energy measurement stage E about 500 μm in thickness. Each thin diode has a cylindrical sensitive volume 9 μm in nominal diameter, similar to that of a cylindrical tissue-equivalent proportional counter (TEPC). The silicon device and a cylindrical TEPC were irradiated in the same experimental conditions with quasi-monoenergetic neutrons of energy between 0.64 and 2.3 MeV at the INFN-Legnaro National Laboratories (LNLINFN, Legnaro (Italy)). The aim was to study the capability of the silicon-based system of reproducing microdosimetric spectra similar to those measured by a reference micro-dosemeter. The TEPC was set in order to simulate a tissue site about 2 μm in diameter. The spectra of the energy imparted to the ΔE stage of the silicon telescope were corrected for tissue-equivalence through an optimized procedure that exploits the information from the residual energy measurement stage E. A geometrical correction based on parametric criteria for shape-equivalence was also applied. The agreement between the dose distributions of lineal energy and the corresponding mean values is satisfactory at each neutron energy considered. (authors)

  9. IRRADIATION OF ETHYLENE DILUTED IN SOLID NITROGEN WITH VACUUM ULTRAVIOLET LIGHT AND ELECTRONS: ITS IMPLICATIONS FOR THE FORMATION OF HCN AND HNC

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hui-Fen [Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung 80708, Taiwan (China); Liu, Meng-Chen; Chen, Sian-Cong; Huang, Tzu-Ping; Wu, Yu-Jong, E-mail: yjwu@nsrrc.org.tw [National Synchrotron Radiation Research Center, No. 101, Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan (China)

    2015-05-01

    Chemical reactions of C{sub 2}H{sub 4} dispersed in solid nitrogen at 10 K that occur upon irradiation with Lyα light at a wavelength of 121.6 nm and 500 eV electrons were investigated by measuring the infrared absorption spectra. Photolysis of the matrix samples with 121.6 nm light yielded products, including C{sub 2}H{sub 2}, CN, and isomers of C{sub 2}N{sub 2}, as well as a pair of HCN and HNC. In contrast, electron bombardment of similar matrix samples mainly resulted in the generation of N{sub 3}, C{sub 2}H{sub 2}, C{sub 2}H{sub 3}, C{sub 3}H{sub 2}, and C{sub 3}N{sup −}. Mechanisms of the reactions that occur during the photolysis and electron-radiation of the matrix samples are discussed. The results of the study provide insights into the formation of HNC and HCN, as well as nitriles, in N{sub 2}-rich ice samples containing a small proportion of C{sub 2}H{sub 4}.

  10. Estimation of track registration efficiency in solution medium and study of gamma irradiation effects on the bulk-etch rate and the activation energy for bulk etching of CR-39 (DOP) Solid State Nuclear Track Detector

    International Nuclear Information System (INIS)

    Kalsi, P.C.

    2010-01-01

    The fission track registration efficiency of diethylene glycol bis allyl carbonate (dioctyl phthalate doped) (CR-39 (DOP)) solid state nuclear track detector (SSNTD) in solution medium (K wet ) has been experimentally determined and is found to be (9.7 ± 0.5).10 -4 cm. This is in good agreement with the values of other SSNTDs. The gamma irradiation effects in the dose range of 50.0-220.0 kGy on the bulk etch rate, V b and the activation energy for bulk etching, E of this solid state nuclear track detector (SSNTD) have also been studied. It is observed that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation

  11. Effect of γ- Ray Irradiation on the Solid Ionic Conductor of (Cul)x(Na3PO4)1-X Materials (x= 0.1 and x= 0.3)

    International Nuclear Information System (INIS)

    Purwanto, P.

    2008-01-01

    Study on the effect of γ- ray irradiation on solid state conductor (Cul) x (Na 3 PO 4 ) 1-X have been done. The solid ionic conductor of (Cul) x (Na 3 PO 4 ) 1-X (x= 0.1 and x= 0.3) had been made by mixing Cul with Na 3 PO 4 by formula of (Cul) x (Na 3 PO 4 ) 1-X where x= 0.1 and x= 0.3 then pressed with 48.26 x 10 6 N/m 2 into pellete in diametre 1.5 x 10 - 2 m. The solid ionic conductor was then γ- ray irradiated with dose of 5 to 30 kGy. The result showed that the structure of (Cul) x (Na 3 PO 4 ) 1-X was Cul and Na 3 PO 4 . Crystall lattice strain of (Cul) x (Na 3 PO 4 ) 1-X were measured stable against the influence of radiation. The conductivity measurement of (Cul) x (Na 3 PO 4 ) 1-X was carried out by LCR at the frequence of 0.1 Hz to 100 kHz. The result showed that the conductivities of (Cul) x (Na 3 PO 4 ) 1-X after irradiation were increasing with radiation dose. (author)

  12. Reduction of allergenicity of irradiated ovalbumin in ovalbumin-allergic mice

    International Nuclear Information System (INIS)

    Seo, Ji-Hyun; Lee, Ju-Woon; Kim, Jae-Hun; Byun, Eui-Baek; Lee, Soo-Young; Kang, Il-Jun; Byun, Myung-Woo

    2007-01-01

    Egg allergy is one of the most serious of the immediate hypersensitivity reactions to foods. Such an allergic disorder is mediated by IgE antibodies stimulated by T-helper type 2 (Th2) lymphocytes. This study was undertaken to evaluate changes of allergenicity and cytokine profiles by exposure of irradiated ovalbumin (OVA), a major allergen of egg white, in the OVA-allergic mice model. OVA solutions (2 mg/ml in 0.01 M phosphate buffered saline (PBS) were gamma-irradiated to 50 and 100 kGy. The allergenicity in the OVA-allergy-induced mice model was remarkably reduced when challenged with irradiated OVA. Cultures of spleen cells harvested from OVA-sensitized mice showed a significant decrease in Th2 cytokine levels of ILs-4 and -5 with a concomitant increase in Th1 cytokine levels of IL-12 when co-cultured with irradiated OVA. However, IFN-γ level decreased dependant on the radiation dose of co-cultured OVA. The levels of IgEs and Th2-cytokine were reduced dependant on the radiation dose. These data show that the irradiated OVA could downregulate the activity of Th2 lymphocytes in OVA-sensitized mice

  13. Bleaching threshold of cationic radicals of alkanes and capture energy of the positive hole of these ions in irradiated solid matrix

    International Nuclear Information System (INIS)

    Van den Bosch, A.; Strobbe, M.; Ceulemans, J.

    1984-01-01

    Gamma irradiated Cl 3 CCF 3 shows an absorption band at about 360 nm, and another band, at 600 nm. The band at 600 nm disappears completely by irradiation with light of lambda>610 nm. Cl 3 CCF 3 containing 1% of decane irradiated at 77 K presents the some phenomena. Selective bleaching by photons of increasing energy allows the determination of the threshold for bleaching of cationic radicals of decane trapped in Cl 3 CCF 3 . Distinction between photoinduced charge transfer and photodissociation is obtained by addition of tetramethyl-p-phenylenediame. Showing that bleaching threshold corresponds to the capture energy of the positive hole on decane cationic radical [fr

  14. Sterilization of proteinaceous food additives by irradiation. Temperature dependent changes in intensity of ESR signals generated by electron beam irradiation

    International Nuclear Information System (INIS)

    Sakaue, Kazushi; Murata, Yoshiyuki; Higashimura, Yutaka; Hayashi, Toru; Todoriki, Setsuko; Tada, Mikiro

    1999-01-01

    Thaumatin, egg white and soybean protein were selected as samples of proteinous food additives, and changes in the intensity of signals appearing in them after they had been irradiated with electron beams were measured by ESR. It was found by such measurement that the positions of signals of thaumatin and soy proteins are nearly the same. Changes in the intensity of radicals in thaumatin calculated on the basis of the coefficients of the respective approximations obtained by using thaumatin which had been irradiated and then stored at 4degC, 25degC, 37degC and 60degC showed that there is a temperature range to determine the remaining of such radicals (inner: 19.7degC, outer: 15.23degC) and that such radicals tend to decrease straight line-wise. It was confirmed that the intensity of signals in the protein powder such thaumatin and soy protein would not be affected at the storage condition below 15degC. (author)

  15. Sterilization of proteinaceous food additives by irradiation. Temperature dependent changes in intensity of ESR signals generated by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sakaue, Kazushi; Murata, Yoshiyuki [Graduate School of Natural Science and Technology, Okayama Univ., Okayama (Japan); Higashimura, Yutaka [San-Ei Gen F.F.I., Inc., Osaka (Japan); Hayashi, Toru; Todoriki, Setsuko [National Food Research Institute, Ministry of Agriculture, Tsukuba, Ibaraki (Japan); Tada, Mikiro [Okayama Univ. (Japan). Faculty of Agriculture

    1999-09-01

    Thaumatin, egg white and soybean protein were selected as samples of proteinous food additives, and changes in the intensity of signals appearing in them after they had been irradiated with electron beams were measured by ESR. It was found by such measurement that the positions of signals of thaumatin and soy proteins are nearly the same. Changes in the intensity of radicals in thaumatin calculated on the basis of the coefficients of the respective approximations obtained by using thaumatin which had been irradiated and then stored at 4degC, 25degC, 37degC and 60degC showed that there is a temperature range to determine the remaining of such radicals (inner: 19.7degC, outer: 15.23degC) and that such radicals tend to decrease straight line-wise. It was confirmed that the intensity of signals in the protein powder such thaumatin and soy protein would not be affected at the storage condition below 15degC. (author)

  16. Hen's egg white hypersensitivity among a group of Egyptian atopic ...

    African Journals Online (AJOL)

    Egyptian Journal of Pediatric Allergy and Immunology (The). Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 12, No 1 (2014) >. Log in or Register to get access to full text downloads.

  17. ISOLATION AND PURIFICATION OF LYSOZYME FROM THE HEN EGG WHITE

    Directory of Open Access Journals (Sweden)

    S. S.

    2015-12-01

    Full Text Available The aim of the research was the development of the method of lysozyme isolation from hen egg proteins. Lysozyme was isolated by differential heat denaturation of proteins with changing of the medium pH value, followed by neutralization, dialysis and additional purification by gel chromatography on Sephadex G-50. Activity was determined by bacteriolytic method (with Micrococcus lysodeikticus 4698 as a substrate. The enzyme purity and molecular mass were determined using SDS-electrophoresis and massspectrometry. The method of lysozyme isolation from hen egg proteins with the enzyme yield of 3.2 ± 0.2% and bacteriolytic activity of 22 025 ± 1 500 U/mg is modified. According to electrophoresis data, the isolated enzyme is characterized by high degree of purity (~95–98% and is comparable with lysozyme of AppliChem company by main physical and chemical characteristics. The obtaining product is stored in a crystalline form at low temperature (–24 оC for 9 months. The proposed method allows obtaining active and stable lysozyme with high purity from hen egg protein in laboratory conditions for the usage in biotechnology.

  18. EPR study of gamma-irradiated N-methyl-L-alanine, DL-2-methyl glutamic acid hemihydrate and Di-leucine hydrochloride in solid state

    Science.gov (United States)

    Sütçü, Kerem; Osmanoğlu, Y. Emre

    2017-12-01

    In this study, it was aimed to investigate ɣ-irradiated powders of N-methyl-L-alanine (NMLA), DL-2-methyl glutamic acid hemihydrate (DL2MGAH), and Di-leucine hydrochloride (DLHCl) at room temperature by electron paramagnetic resonance spectroscopy. After the γ-irradiation the samples indicated the existence of the CH3ĊNHCH3COOH, HOOCCH3NH2CĊHCH2COOH·1/2H2O and (CH3)2ĊCH2CH NHCOOHCOCH (NH2HCl) CH2CH (CH3)2 radicals, respectively. The spectral parameters of the radicals were determined. The results were compared with the earlier studies and discussed accordingly.

  19. DEGRADATION OF SOLAR CELLS PARAMETERS FABRICATED ON THE BASIS OF Cu(In,GaSe2 SEMICONDUCTOR SOLID SOLUTIONS UNDER ELECTRON IRRADIATION

    Directory of Open Access Journals (Sweden)

    A. V. Mudryi

    2014-01-01

    Full Text Available Polycrystalline Cu(In,GaSe2 (CIGS thin films were grown on molybdenum-coated soda-lime glass substrates by co-evaporation of the elements Cu, In, Ga and Se from independent sources. The effect of electron irradiation on the electrical and optical properties of CIGS thin films and solar cells with the structure ZnO:Al/i-ZnO/CdS/CIGS/Mo/glass was studied. It was found that the degradation of the electrical parameters of solar cells (open-circuit voltage, short-circuit current density and efficiency took place due to the formation of radiation defects (recombination centers with deep energy levels in the bandgap of CIGS. It was revealed that after electron irradiation intensity of near band-edge luminescence band at about 1,1 eV decreased considerably and bands of luminescence with maxima at 0,93 and 0,75 eV appeared.

  20. Effect of time between x-irradiation and chemotherapy on the growth of three solid mouse tumors. IV. Actinomycin-d

    International Nuclear Information System (INIS)

    Twentyman, P.R.; Kallman, R.F.; Brown, J.M.

    1979-01-01

    Experiments have been carried out to determine the effect of different intervals between the administration of x-radiation (1200 rad) and actinomycin-D (200 μg/kg) on the growth delay produced in three mouse tumors. The tumors used were the EMT6 tumor in BALB/c mice and the KHT and RIF-1 sarcomas in C3H mice. All tumors were grown intramuscularly in the gastrocnemius muscle, and treatment was carried out at a mean tumor weight of 450 mg. Time to reach 2 x (for KHT) or 4 x (for EMT6 and RIF-1) treatment volume was used as the endpoint of response. The drug was administered intraperitoneally either 24, 6, or 2 hr before radiation, immediately before the start of radiation, or 3, 6, or 24 hr after radiation. All irradiations were carried out in unanesthetized mice. For a single administration at this dose level (close to the maximum tolerated dose) actinomycin-D did not produce a significant delay in the growth of any of the tumors. For the RIF-1 and KHT tumors, the growth delays produced by drug/radiation combinations generally were not significantly greater than that produced by irradiation alone. For the EMT6 tumor, great variability in the growth delays of combined modality groups seen, with mean growth delays significantly longer than predicted by the radiation alone data. No consistent dependence on timing between irradiation and drug administration was seen

  1. L-shell emission from high-Z solid targets by intense (10{sup 19}W/cm{sup 2}) irradiation with a 248nm laser

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, T. R.; Borisov, A. B.; Boyer, K.; Schroeder, W. A.; Santoro, J.; Van Tassle, A. J.; Rhodes, C. K.; Luk, T. S.; Cameron, S.; Longworth, J. W.; McPherson, A.

    1999-11-22

    Efficient (1.2% yield) multikilovolt x-ray emission from Ba(L) (2.4--2.8{angstrom}) and Gd(L) (1.7--2.1{angstrom}) is produced by ultraviolet (248nm) laser-excited BaF{sub 2} and Gd solids. The high efficiency is attributed to an inner shell-selective collisional electron ejection.

  2. Proton glass behaviour in a solid solution of gamma-irradiated deuterated betaine phosphate sub 0 sub . sub 1 sub 5 betaine phosphite sub 0 sub . sub 8 sub 5

    CERN Document Server

    Banys, J; Klimm, C; Voelkel, G; Kloepperpieper, A

    1997-01-01

    Measurements of the dielectric permittivity are reported for a deuterated solid solution of gamma-irradiated antiferroelectric (betainephosphate) sub 0 sub . sub 1 sub 5 ferroelectric (betainephosphite) sub 0 sub . sub 8 sub 5 at frequencies 20 H sub Z

  3. Interstitial irradiation for craniopharyngioma

    International Nuclear Information System (INIS)

    Barlas, O.; Bayindir, C.; Can, M.

    2000-01-01

    The results of interstitial irradiation treatment for craniopharyngioma in two patients with six year follow-ups are presented. Stereotactic interstitial irradiation with iodine-125 sources as sole therapy was employed in two adult patients who refused surgical resection. The diagnoses were confirmed by stereotactic biopsy. The first tumour which underwent interstitial irradiation was solid and 4 cm in diameter, and the second, 2.7 cm in diameter, had both cystic and solid components. The implanted iodine-125 seeds delivered 67 Gy and 60 Gy to tumour periphery at the rate of 12 and 14 cGy/h, respectively, were removed at the end of designated radiation periods. Tumour shrinkage and central hypo density, first observed 3 months after irradiation, continued until one tumour shrank to less than 1 cm at 12 months, and the other disappeared completely at 24 months. In both cases functional integrity was restored, and neither radiation induced toxicity nor recurrence has occurred six years after treatment. The results in these two cases suggest that solid craniopharyngiomas are sensitive to interstitial irradiation. (author)

  4. Total integrated dose testing of solid-state scientific CD4011, CD4013, and CD4060 devices by irradiation with CO-60 gamma rays

    Science.gov (United States)

    Dantas, A. R. V.; Gauthier, M. K.; Coss, J. R.

    1985-01-01

    The total integrated dose response of three CMOS devices manufactured by Solid State Scientific has been measured using CO-60 gamma rays. Key parameter measurements were made and compared for each device type. The data show that the CD4011, CD4013, and CD4060 produced by this manufacturers should not be used in any environments where radiation levels might exceed 1,000 rad(Si).

  5. Irradiation of foods of animal origin

    International Nuclear Information System (INIS)

    Purkarevic, A.

    1985-01-01

    A system is suggested which permits the irradiation of liquid and semi-solid materials, using wasted radiation in conventional package irradiation plants. Various appliances control the flow parameters, temperature, and environment during irradiation. As possible materials, various derivatives of the meat industry are suggested

  6. Alloys under irradiation

    International Nuclear Information System (INIS)

    Martin, G.; Bellon, P.; Soisson, F.

    1997-01-01

    During the last two decades, some effort has been devoted to establishing a phenomenology for alloys under irradiation. Theoretically, the effects of the defect supersaturation, sustained defect fluxes and ballistic mixing on solid solubility under irradiation can now be formulated in a unified manner, at least for the most simple cases: coherent phase transformations and nearest-neighbor ballistic jumps. Even under such restrictive conditions, several intriguing features documented experimentally can be rationalized, sometimes in a quantitative manner and simple qualitative rules for alloy stability as a function of irradiation conditions can be formulated. A quasi-thermodynamic formalism can be proposed for alloys under irradiation. However, this point of view has limits illustrated by recent computer simulations. (orig.)

  7. Food irradiation

    International Nuclear Information System (INIS)

    Soothill, R.

    1987-01-01

    The issue of food irradiation has become important in Australia and overseas. This article discusses the results of the Australian Consumers' Association's (ACA) Inquiry into food irradiation, commissioned by the Federal Government. Issues discussed include: what is food irradiation; why irradiate food; how much food is consumer rights; and national regulations

  8. Food irradiation

    International Nuclear Information System (INIS)

    Lindqvist, H.

    1996-01-01

    This paper is a review of food irradiation and lists plants for food irradiation in the world. Possible applications for irradiation are discussed, and changes induced in food from radiation, nutritional as well as organoleptic, are reviewed. Possible toxicological risks with irradiated food and risks from alternative methods for treatment are also brought up. Ways to analyze weather food has been irradiated or not are presented. 8 refs

  9. Production of Imitated fish and Keeping their Quality by gamma irradiation

    International Nuclear Information System (INIS)

    Ali, H.E.S.

    2004-01-01

    this investigation aims to the possibility of utilizing the bolti fish which obtained from high dam lake specially large size and under utilized for manufacturing imitated shellfish product and compared with natural shell fish and also, aims to study the possibility of gamma irradiation at doses 1,3,and 5 kGy for keeping the quality of imitated fish product during cold storage. therefore whole fish bolti were obtained from Misr Aswan company. the whole fish were dressed and minced. the obtained minced fish was washed three times with sodium bicarbonate (0.2%), distilled water and sodium chloride solution (0.15%). the cryoprotectant ingredient (sorbitol, sucrose and tripoli phosphate) was added to washed minced fish for producing intermediate product (surimi). the final product (imitated fish) was manufactured by adding egg white, starch, corn oil, natural color and flavor of shrimp and crab according to special formula for shrimp and crab. the imitated shrimp sample were irradiated at doses 1,3 and 5 kGy and sold stored

  10. Effect of irradiation on sweet corn preservation

    International Nuclear Information System (INIS)

    Fu Junjie

    2002-01-01

    60 Co γ-ray was used to irradiate newly-harvested sweet corn and the results showed that the effects of irradiation on soluble solids, sucrose, starch and total sugar were not significant. The viscosity of starch decreased with the increasing of irradiation dose. The preservation duration of irradiated sweet corn was 7 days longer than that of CK, and the sweet, smell, taste of sweet corn had no abnormal change

  11. Irradiation behaviour of solid and hollow U{sub 3}Si fuel elements: results to 15,000 MWd/tonne U

    Energy Technology Data Exchange (ETDEWEB)

    Feraday, M A; Chalder, G H; Cotnam, K D

    1969-06-15

    U{sub 3}Si fuel elements clad in zirconium alloy sheaths have been irradiated to burnups close to 15,000 MWd/tonne U in pressurized water at 220{sup o}C, 98 bars. The results show that the external swelling can be controlled by incorporating free volume in the element. The dimensional stability of such elements is adequate to permit their use in power reactor fuel bundles. A diameter increase of 1.2% had occurred in an element initially containing 12.8% total free volume, after a burnup of 14,700 MWd/tonne U. There was no change in diameter between burnups of 5200 and 14,700 MWd/tonne U. Elements containing 3% total free volume had increased in diameter about 2.5% at 2000 MWd/tonne U compared to 0.2% at 9500 MWd/tonne U for elements containing 22% total free volume. The observed swelling in the U{sub 3}Si is discussed in terms of possible mechanisms. (author)

  12. Gamma irradiation up to 109 rads of all silica fibers, comparison with polymer clad silica fibers and solid sample between 0.4 and 2.5 micrometers

    International Nuclear Information System (INIS)

    Boisde, G.; Bonnejean, C.; Perez, J.J.; Neumann, V.; Wurier, B.; Boucher, D.

    1983-05-01

    The effect of γ radiation (Co 60 ) on optical fibers is studied for investigations to remote measurement in irradiating environments. The spectral characteristics of PCS and AS silica fibers, PCS ''Wet'' and AS ''wet'' and ''superwet'' are compared. An automatic computerized system for measurement ''in situ'' is used between 0,4 AND 1,1 micron. Radiation-induced effects are examined at 840nm on PCS, AS with silicone, AS with epoxy (200 and 400/600μm) up to 5.10 8 rads. Samples of ''dry'', ''wet'', ''superwet'' and ''doped fluor'' silica are studied up to 1,3.10 9 rads between 0,3 and 2,5 μm. The photobleaching, the radiation hardening and the breakeage of PCS and AS-silicone after 10 7 rads are recognized. The spectral characteristics of a band at 610-630nm, a spectral deformation at 945nm for ''wet'' fibers and a peak of the radiation-induced attenuation are observed. The kinetic of the 630nm defect in silica fibers and silica samples is also investigated [fr

  13. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gruenewald, T

    1985-01-01

    Food irradiation has become a matter of topical interest also in the Federal Republic of Germany following applications for exemptions concerning irradiation tests of spices. After risks to human health by irradiation doses up to a level sufficient for product pasteurization were excluded, irradiation now offers a method suitable primarily for the disinfestation of fruit and decontamination of frozen and dried food. Codex Alimentarius standards which refer also to supervision and dosimetry have been established; they should be adopted as national law. However, in the majority of cases where individual countries including EC member-countries so far permitted food irradiation, these standards were not yet used. Approved irradiation technique for industrial use is available. Several industrial food irradiation plants, partly working also on a contractual basis, are already in operation in various countries. Consumer response still is largely unknown; since irradiated food is labelled, consumption of irradiated food will be decided upon by consumers.

  14. Acquisition of reproducible transmission near-infrared (NIR) spectra of solid samples with inconsistent shapes by irradiation with isotropically diffused radiation using polytetrafluoroethylene (PTFE) beads.

    Science.gov (United States)

    Lee, Jinah; Duy, Pham Khac; Yoon, Jihye; Chung, Hoeil

    2014-06-21

    A bead-incorporated transmission scheme (BITS) has been demonstrated for collecting reproducible transmission near-infrared (NIR) spectra of samples with inconsistent shapes. Isotropically diffused NIR radiation was applied around a sample and the surrounding radiation was allowed to interact homogeneously with the sample for transmission measurement. Samples were packed in 1.40 mm polytetrafluoroethylene (PTFE) beads, ideal diffusers without NIR absorption, and then transmission spectra were collected by illuminating the sample-containing beads using NIR radiation. When collimated radiation was directly applied, a small portion of the non-fully diffused radiation (NFDR) propagated through the void space of the packing and eventually degraded the reproducibility. Pre-diffused radiation was introduced by placing an additional PTFE disk in front of the packing to diminish NFDR, which produced more reproducible spectral features. The proposed scheme was evaluated by analyzing two different solid samples: density determination for individual polyethylene (PE) pellets and identification of mining locality for tourmalines. Because spectral collection was reproducible, the use of the spectrum acquired from one PE pellet was sufficient to accurately determine the density of nine other pellets with different shapes. The differentiation of tourmalines, which are even more dissimilar in appearance, according to their mining locality was also feasible with the help of the scheme.

  15. Effect of gamma irradiation and environmental factors on the production of extracellular cellulase enzyme by trichoderma Spp. using banana waste under solid state bio processing

    International Nuclear Information System (INIS)

    El-Shafey, H.M.; Matar, Z.A.I.; Ghanem, S.M.A.

    2007-01-01

    Fungal strains were isolated from degraded banana waste including leaves, pseudo stems and skins. Many isolated strains showed cellulolytic activities using the plate screening medium. The hyper cellulolytic isolates were selected on the basis of the diameter of the hydrolysis zone surrounding the colonies and identified to the genus level. The identified strains were found to belong to one of the genera Trichoderma, Aspergillus, Pleurotus or Penicillium. The strain with the larger diameter of the hydrolysis zone was found to belong to the genus Trichoderma. It was further identified to be Trichoderma harzianum, which was selected to be studied. Banana waste including leaves and pseudo stems were inoculated by the selected fungus and the production of the carboxymethyl cellulase (CMCase) and filter paper cellulase (FPCase) was followed during changes of the growth conditions under solid state fermentation. It was found that the two enzymes shared the same incubation temperature (25 degree C) and incubation period (18 days) for the maximum enzyme production. The gamma radiation dose of 1.5 KGy increased the production of CMCase produced on leaves by 4.0% and on pseudo stems by 5.6% and the production of FPCase produced on leaves by 2.4% and on pseudo stems by 2.3%. The results also suggest that FPCase and CMCase enzymes produced on leaves were higher than those produced from pseudo stems and the level of CMCase enzyme produced was higher than that of FPCase

  16. Formation of amorphous layers by irradiation

    International Nuclear Information System (INIS)

    Bourgoin, J.C.

    1979-01-01

    When an ordered solid is irradiated with heavy energy particles, disorder is produced. When the irradiation dose exceeds a so-called critical dose, the irradiated area of the solid becomes uniformly disordered. Mention is first made of the nature, concentration and distribution of the defects created by a heavy energy particle. The description is then given -solely with respect to semiconductors- of the effect of the various parameters on the critical dose energy and nature of the ion, nature and temperature of the solid, irradiation flux. The physical properties (electronic and thermodynamic types) and the uniformly disordered areas are briefly discussed and these properties are compared with those of amorphous semiconductor layers fabricated by evaporation. It is concluded that the evaporated and irradiated layers are similar in nature. It is suggested that the transformation of an irradiated crystalline area into an amorphous one occurs when the Gibbs energy of the crystal become greater than the Gibbs energy of the amorphous one [fr

  17. Food irradiation

    International Nuclear Information System (INIS)

    Sato, Tomotaro; Aoki, Shohei

    1976-01-01

    Definition and significance of food irradiation were described. The details of its development and present state were also described. The effect of the irradiation on Irish potatoes, onions, wiener sausages, kamaboko (boiled fish-paste), and mandarin oranges was evaluated; and healthiness of food irradiation was discussed. Studies of the irradiation equipment for Irish potatoes in a large-sized container, and the silo-typed irradiation equipment for rice and wheat were mentioned. Shihoro RI center in Hokkaido which was put to practical use for the irradiation of Irish potatoes was introduced. The state of permission of food irradiation in foreign countries in 1975 was introduced. As a view of the food irradiation in the future, its utilization for the prevention of epidemics due to imported foods was mentioned. (Serizawa, K.)

  18. Gamma irradiator

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

    Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

  19. Food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The article explains what radiation does to food to preserve it. Food irradiation is of economic importance to Canada because Atomic Energy of Canada Limited is the leading world supplier of industrial irradiators. Progress is being made towards changing regulations which have restricted the irradiation of food in the United States and Canada. Examples are given of applications in other countries. Opposition to food irradiation by antinuclear groups is addressed

  20. Food irradiation

    International Nuclear Information System (INIS)

    Beyers, M.

    1977-01-01

    The objectives of food irradiation are outlined. The interaction of irradiation with matter is then discussed with special reference to the major constituents of foods. The application of chemical analysis in the evaluation of the wholesomeness of irradiated foods is summarized [af

  1. Food irradiation

    International Nuclear Information System (INIS)

    Macklin, M.

    1987-01-01

    The Queensland Government has given its support the establishment of a food irradiation plant in Queensland. The decision to press ahead with a food irradiation plant is astonishing given that there are two independent inquiries being carried out into food irradiation - a Parliamentary Committee inquiry and an inquiry by the Australian Consumers Association, both of which have still to table their Reports. It is fair to assume from the Queensland Government's response to date, therefore, that the Government will proceed with its food irradiation proposals regardless of the outcomes of the various federal inquiries. The reasons for the Australian Democrats' opposition to food irradiation which are also those of concerned citizens are outlined

  2. Food irradiation

    International Nuclear Information System (INIS)

    Duchacek, V.

    1989-01-01

    The ranges of doses used for food irradiation and their effect on the processed foods are outlined. The wholesomeness of irradiated foods is discussed. The present food irradiation technology development in the world is described. A review of the irradiated foods permitted for public consumption, the purposes of food irradiaton, the doses used and a review of the commercial-scale food irradiators are tabulated. The history and the present state of food processing in Czechoslovakia are described. (author). 1 fig., 3 tabs., 13 refs

  3. Irradiated foods

    International Nuclear Information System (INIS)

    Darrington, Hugh

    1988-06-01

    This special edition of 'Food Manufacture' presents papers on the following aspects of the use of irradiation in the food industry:- 1) an outline view of current technology and its potential. 2) Safety and wholesomeness of irradiated and non-irradiated foods. 3) A review of the known effects of irradiation on packaging. 4) The problems of regulating the use of irradiation and consumer protection against abuse. 5) The detection problem - current procedures. 6) Description of the Gammaster BV plant in Holland. 7) World outline review. 8) Current and future commercial activities in Europe. (U.K.)

  4. Self-irradiation effect on thermal conductivity of Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N solid solution

    Energy Technology Data Exchange (ETDEWEB)

    Nishi, Tsuyoshi, E-mail: tsuyoshi.nishi.75@vc.ibaraki.ac.jp [Department of Materials Science and Engineering, College of Engineering, Ibaraki University, Hitachi, Ibaraki, 316-8511 (Japan); Hayashi, Hirokazu; Sato, Takumi; Takano, Masahide [Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Tokai-mura, Ibaraki, 319-1195 (Japan)

    2017-04-01

    This study evaluated the dependence of the thermal conductivity of Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N on storage time and temperature. The authors prepared sintered samples of Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N solid solution and measured thermal diffusivity at storage times of 0, 24, 72, 144, 240, 408, 552, 816, 1,680, and 2064 h, from which it was determined that the thermal conductivity decreased exponentially with increasing storage time. This result suggests that the decrease of the thermal conductivity could be attributed to the accumulation of lattice defects from self-irradiation. To confirm the thermal recovery behavior of Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N under annealing, thermal diffusivity was also measured just after annealing. The thermal conductivity of Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N was determined to be larger than that of Zr{sub 0.58}Pu{sub 0.21}Cm{sub 0.21}N but smaller than that of Zr{sub 0.80}Pu{sub 0.10}Cm{sub 0.10}N. - Highlights: •The authors prepared Zr{sub 0.70}Pu{sub 0.25}Cm{sub 0.05}N and measured thermal diffusivity. •Dependence of thermal conductivity on storage time was clarified. •After annealing at 1423 K in vacuum, thermal conductivity was recovered.

  5. Interest of the grazing X ray diffraction to study the evolution of materials under irradiation: behaviour of zirconia under irradiation; Utilisation de la diffraction des rayons X en incidence rasante pour l'etude des solides irradies: application a la zircone

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, D.; Gosset, D.; Bechade, J.L. [CEA Saclay, Dept. des Materiaux pour le Nucleaire DMN, 91 - Gif-sur-Yvette (France)

    2001-07-01

    This document was written to show that grazing X ray diffraction may be a powerful tool to study irradiation damages induced by ion beams in materials. Taking advantage of an asymmetric geometry and a curved detector, it is possible to analyse accurately diffraction diagrams at low angles by taking into account the specific effects induced by the grazing incidence. The interest of grazing incidence is to control the penetration depth of X rays. Such possibility allows to separate effects induced by damages (displacement cascades) and the implantation peak (elastic deformation of the lattice due to the insertion of projectile ions in the matrix). A Rietveld analysis on grazing X ray diagrams shows clearly that displacement cascades induce a phase transition on irradiated zirconia. (authors)

  6. Interest of the grazing X ray diffraction to study the evolution of materials under irradiation: behaviour of zirconia under irradiation; Utilisation de la diffraction des rayons X en incidence rasante pour l'etude des solides irradies: application a la zircone

    Energy Technology Data Exchange (ETDEWEB)

    Simeone, D; Gosset, D; Bechade, J L [CEA Saclay, Dept. des Materiaux pour le Nucleaire DMN, 91 - Gif-sur-Yvette (France)

    2001-07-01

    This document was written to show that grazing X ray diffraction may be a powerful tool to study irradiation damages induced by ion beams in materials. Taking advantage of an asymmetric geometry and a curved detector, it is possible to analyse accurately diffraction diagrams at low angles by taking into account the specific effects induced by the grazing incidence. The interest of grazing incidence is to control the penetration depth of X rays. Such possibility allows to separate effects induced by damages (displacement cascades) and the implantation peak (elastic deformation of the lattice due to the insertion of projectile ions in the matrix). A Rietveld analysis on grazing X ray diagrams shows clearly that displacement cascades induce a phase transition on irradiated zirconia. (authors)

  7. Foodstuff irradiation

    International Nuclear Information System (INIS)

    1982-01-01

    Report written on behalf of the Danish Food Institute summarizes national and international rules and developments within food irradiation technology, chemical changes in irradiated foodstuffs, microbiological and health-related aspects of irradiation and finally technological prospects of this conservation form. Food irradiatin has not been hitherto applied in Denmark. Radiation sources and secondary radiation doses in processed food are characterized. Chemical changes due to irradiation are compared to those due to p.ex. food heating. Toxicological and microbiological tests and their results give no unequivocal answer to the problem whether a foodstuff has been irradiated. The most likely application fields in Denmark are for low radiation dosis inhibition of germination, riping delay and insecticide. Medium dosis (1-10 kGy) can reduce bacteria number while high dosis (10-50 kGy) will enable total elimination of microorganisms and viruses. Food irradiation can be acceptable as technological possibility with reservation, that further studies follow. (EG)

  8. Hemibody irradiation

    International Nuclear Information System (INIS)

    Schen, B.C.; Mella, O.; Dahl, O.

    1992-01-01

    In a large number of cancer patients, extensive skeletal metastases or myelomatosis induce vast suffering, such as intolerable pain and local complications of neoplastic bone destruction. Analgetic drugs frequently do not yield sufficient palliation. Irradiation of local fields often has to be repeated, because of tumour growth outside previously irradiated volumes. Wide field irradiation of the lower or upper half of the body causes significant relief of pain in most patients. Adequate pretreatment handling of patients, method of irradiation, and follow-up are of importance to reduce side effects, and are described as they are carried out at the Department of Oncology, Haukeland Hospital, Norway. 16 refs., 2 figs

  9. Studies in solid state ionics

    International Nuclear Information System (INIS)

    Jakes, D.; Rosenkranz, J.

    1987-01-01

    Studies performed over 10 years by the high temperature chemistry group are reviewed. Attention was paid to different aspects of ionic solids from the point of view of practical as well as theoretical needs of nuclear technology. Thus ceramic fuel compound like uranates, urania-thoria system, solid electrolytes based on oxides and ionics transformations were studied under reactor irradiation. (author) 13 figs., 3 tabs., 46 refs

  10. Food irradiation

    International Nuclear Information System (INIS)

    Mercader, J.P.; Emily Leong

    1985-01-01

    The paper discusses the need for effective and efficient technologies in improving the food handling system. It defines the basic premises for the development of food handling. The application of food irradiation technology is briefly discussed. The paper points out key considerations for the adoption of food irradiation technology in the ASEAN region (author)

  11. Food irradiation

    International Nuclear Information System (INIS)

    Matsuyama, Akira

    1990-01-01

    This paper reviews researches, commentaries, and conference and public records of food irradiation, published mainly during the period 1987-1989, focusing on the current conditions of food irradiation that may pose not only scientific or technologic problems but also political issues or consumerism. Approximately 50 kinds of food, although not enough to fill economic benefit, are now permitted for food irradiation in the world. Consumerism is pointed out as the major factor that precludes the feasibility of food irradiation in the world. In the United States, irradiation is feasible only for spices. Food irradiation has already been feasible in France, Hollands, Belgium, and the Soviet Union; has under consideration in the Great Britain, and has been rejected in the West Germany. Although the feasibility of food irradiation is projected to increase gradually in the future, commercial success or failure depends on the final selection of consumers. In this respect, the role of education and public information are stressed. Meat radicidation and recent progress in the method for detecting irradiated food are referred to. (N.K.) 128 refs

  12. Irradiation proctitis

    International Nuclear Information System (INIS)

    Minami, Akira

    1977-01-01

    Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures. (Kanao, N.)

  13. Irradiation proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Minami, A [Osaka Kita Tsishin Hospital (Japan)

    1977-06-01

    Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures.

  14. Food irradiation

    International Nuclear Information System (INIS)

    Kobayashi, Yasuhiko; Kikuchi, Masahiro

    2009-01-01

    Food irradiation can have a number of beneficial effects, including prevention of sprouting; control of insects, parasites, pathogenic and spoilage bacteria, moulds and yeasts; and sterilization, which enables commodities to be stored for long periods. It is most unlikely that all these potential applications will prove commercially acceptable; the extend to which such acceptance is eventually achieved will be determined by practical and economic considerations. A review of the available scientific literature indicates that food irradiation is a thoroughly tested food technology. Safety studies have so far shown no deleterious effects. Irradiation will help to ensure a safer and more plentiful food supply by extending shelf-life and by inactivating pests and pathogens. As long as requirement for good manufacturing practice are implemented, food irradiation is safe and effective. Possible risks of food irradiation are not basically different from those resulting from misuse of other processing methods, such as canning, freezing and pasteurization. (author)

  15. Irradiation damage

    Energy Technology Data Exchange (ETDEWEB)

    Howe, L.M

    2000-07-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

  16. Irradiation damage

    International Nuclear Information System (INIS)

    Howe, L.M.

    2000-01-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization

  17. Irradiation effects on perfluorinated polymers

    International Nuclear Information System (INIS)

    Lappan, U.; Geissler, U.; Haeussler, L.; Pompe, G.; Scheler, U.; Lunkwitz, K.

    2002-01-01

    Complete text of publication follows. High-energy radiation affects the properties of polymers by chain scission and crosslinking reactions. Both types of reaction occur simultaneously in irradiated polymers. However, one process will usually predominate, depending on the chemical structure of the polymer and the irradiation conditions such as temperature and atmosphere. Polytetrafluoroethylene (PTFE) undergoes predominantly chain scission, if the irradiation is performed at room temperature. This shortcoming is exploited by converting PTFE into low molecular weight micropowders. The use of PTFE micropowders functionalized with COOH groups as additive in polyamides to improve the sliding properties of the materials has been studied. During the compounding process in a twin screw extruder the COOH groups of the irradiated PTFE react with the polyamides. For these studies, it became necessary to investigate the content of end groups in irradiated PTFE by FTIR and 19 F solid-state NMR. These date were used to calculate number-average molecular weights. The ratios of COOH groups to CF 3 groups are discussed in terms of the mechanism of PTFE degradation. If PTFE is irradiated at temperatures above its crystalline melting point in an oxygen-free atmosphere, branching and crosslinking occur. The dependence of radiation effects on perfluorinated copolymers (FEP, PFA) on temperature has been studied. Melt flow index measurements have shown that branching and crosslinking predominate over chain scission with increasing irradiation temperature both in FEP and in PFA. Quantitative analysis of 19 F solid-state NMR data has shown that the content of branching groups (>CF-) exceeds the content of end groups in the case of PFA irradiated above its crystalline melting point. The formation of COF and COOH groups in the irradiated PFA is interpreted as a result of partial degradation of perfluorovinyl ether comonomer units

  18. /sup 99m/Tc-labeled solid-phase meal: a quantitative clinical measurement of human gastric emptying

    International Nuclear Information System (INIS)

    Martin, J.L.; Beck, W.J.; McDonald, A.P.; Carlson, G.M.; Mathias, J.R.

    1983-01-01

    A solid-phase meal labeled with /sup 99m/Tc-sulfur colloid provides an improved clinical test for the quantitative evaluation of human gastric emptying. We studied 12 healthy male controls and five male patients with known gastric stasis secondary to a vagotomy and drainage procedure. All subjects were fasted for 8 hours before the study, and each consumed an unbuttered biscuit and a poached egg white containing 1 mCi of /sup 99m/Tc-sulfur colloid. For 2 hours, 60-second counts were measured every 10 minutes by a Pho Gamma III scintillation camera. The t 1 / 2 for control subjects was 60 minutes, at which time patients with gastric stasis had retained 98% of the test meal. At 120 minutes, control subjects and patients with gastric stasis had 4.7% and 89%, respectively, of the meal remaining in the stomach. The solid-phase test meal labeled with /sup 99m/Tc-sulfur colloid is easy to perform and can be used clinically to quantitatively measure gastric emptying in humans. This test can discriminate between control subjects and patients with known gastric stasis

  19. /sup 99m/Tc-labeled solid-phase meal: a quantitative clinical measurement of human gastric emptying

    Energy Technology Data Exchange (ETDEWEB)

    Martin, J.L.; Beck, W.J.; McDonald, A.P.; Carlson, G.M.; Mathias, J.R.

    1983-08-01

    A solid-phase meal labeled with /sup 99m/Tc-sulfur colloid provides an improved clinical test for the quantitative evaluation of human gastric emptying. We studied 12 healthy male controls and five male patients with known gastric stasis secondary to a vagotomy and drainage procedure. All subjects were fasted for 8 hours before the study, and each consumed an unbuttered biscuit and a poached egg white containing 1 mCi of /sup 99m/Tc-sulfur colloid. For 2 hours, 60-second counts were measured every 10 minutes by a Pho Gamma III scintillation camera. The t/sup 1///sup 2/ for control subjects was 60 minutes, at which time patients with gastric stasis had retained 98% of the test meal. At 120 minutes, control subjects and patients with gastric stasis had 4.7% and 89%, respectively, of the meal remaining in the stomach. The solid-phase test meal labeled with /sup 99m/Tc-sulfur colloid is easy to perform and can be used clinically to quantitatively measure gastric emptying in humans. This test can discriminate between control subjects and patients with known gastric stasis.

  20. Food irradiation

    International Nuclear Information System (INIS)

    Hetherington, M.

    1989-01-01

    This popular-level article emphasizes that the ultimate health effects of irradiated food products are unknown. They may include vitamin loss, contamination of food by botulism bacteria, mutations in bacteria, increased production of aflatoxins, changes in food, carcinogenesis from unknown causes, presence of miscellaneous harmful chemicals, and the lack of a way of for a consumer to detect irradiated food. It is claimed that the nuclear industry is applying pressure on the Canadian government to relax labeling requirements on packages of irradiated food in order to find a market for its otherwise unnecessary products

  1. Food irradiation

    International Nuclear Information System (INIS)

    Luecher, O.

    1979-01-01

    Limitations of existing preserving methods and possibilities of improved food preservation by application of nuclear energy are explained. The latest state-of-the-art in irradiation technology in individual countries is described and corresponding recommendations of FAO, WHO and IAEA specialists are presented. The Sulzer irradiation equipment for potato sprout blocking is described, the same equipment being suitable also for the treatment of onions, garlic, rice, maize and other cereals. Systems with a higher power degree are needed for fodder preserving irradiation. (author)

  2. URAM-2 Cryogenic Irradiation Facility

    CERN Document Server

    Shabalin, E P; Kulikov, S A; Kulagin, E N; Melihov, V V; Belyakov, A A; Golovanov, L B; Borzunov, Yu T; Konstantinov, V I; Androsov, A V

    2002-01-01

    The URAM-2 irradiation facility has been built and mounted at the channel No. 3 of the IBR-2 reactor. It was constructed for study of radiolysis effects by fast neutron irradiation in some suitable for effective cold neutron production materials (namely: solid methane, methane hydrate, water ice, etc.). The facility cooling system is based on using liquid helium as a coolant material. The original charging block of the rig allows the samples to be loaded by condensing gas into irradiation cavity or by charging beads of ice prepared before. Preliminary tests for each facility block and assembling them at the working position were carried out. Use of the facility for study accumulation of chemical energy under irradiation at low temperature in materials mentioned above and its spontaneous release was started.

  3. Food irradiation

    International Nuclear Information System (INIS)

    Paganini, M.C.

    1991-06-01

    Food treatment by means of ionizing energy, or irradiation, is an innovative method for its preservation. In order to treat important volumes of food, it is necessary to have industrial irradiation installations. The effect of radiations on food is analyzed in the present special work and a calculus scheme for an Irradiation Plant is proposed, discussing different aspects related to its project and design: ionizing radiation sources, adequate civil work, security and auxiliary systems to the installations, dosimetric methods and financing evaluation methods of the project. Finally, the conceptual design and calculus of an irradiation industrial plant of tubercles is made, based on the actual needs of a specific agricultural zone of our country. (Author) [es

  4. Food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Food preservation by irradiation is one part of Eisenhower's Atoms for Peace program that is enjoying renewed interest. Classified as a food additive by the Food, Drug, and Cosmetic Act of 1958 instead of a processing technique, irradiation lost public acceptance. Experiments have not been done to prove that there are no health hazards from gamma radiation, but there are new pressures to get Food and Drug Administration approval for testing in order to make commercial use of some radioactive wastes. Irradiation causes chemical reactions and nutritional changes, including the destruction of several vitamins, as well as the production of radiolytic products not normally found in food that could have adverse effects. The author concludes that, lacking epidemiological evidence, willing buyers should be able to purchase irradiated food as long as it is properly labeled

  5. Fruit irradiation

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Food spoilage is a common problem when marketing agricultural products. Promising results have already been obtained on a number of food irradiating applications. A process is described in this paper where irradiation of sub-tropical fruits, especially mangoes and papayas, combined with conventional heat treatment results in effective insect and fungal control, delays ripening and greatly improves the quality of fruit at both export and internal markets

  6. Tissue irradiator

    International Nuclear Information System (INIS)

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

    1975-01-01

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

  7. Blood irradiation

    International Nuclear Information System (INIS)

    Chandy, Mammen

    1998-01-01

    Viable lymphocytes are present in blood and cellular blood components used for transfusion. If the patient who receives a blood transfusion is immunocompetent these lymphocytes are destroyed immediately. However if the patient is immunodefficient or immunosuppressed the transfused lymphocytes survive, recognize the recipient as foreign and react producing a devastating and most often fatal syndrome of transfusion graft versus host disease [T-GVHD]. Even immunocompetent individuals can develop T-GVHD if the donor is a first degree relative since like the Trojan horse the transfused lymphocytes escape detection by the recipient's immune system, multiply and attack recipient tissues. T-GVHD can be prevented by irradiating the blood and different centers use doses ranging from 1.5 to 4.5 Gy. All transfusions where the donor is a first degree relative and transfusions to neonates, immunosuppressed patients and bone marrow transplant recipients need to be irradiated. Commercial irradiators specifically designed for irradiation of blood and cellular blood components are available: however they are expensive. India needs to have blood irradiation facilities available in all large tertiary institutions where immunosuppressed patients are treated. The Atomic Energy Commission of India needs to develop a blood irradiator which meets international standards for use in tertiary medical institutions in the country. (author)

  8. Food irradiation

    International Nuclear Information System (INIS)

    Migdal, W.

    1995-01-01

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

  9. Food irradiation

    International Nuclear Information System (INIS)

    1991-01-01

    Processing of food with low levels of radiation has the potential to contribute to reducing both spoilage of food during storage - a particular problem in developing countries - and the high incidence of food-borne disease currently seen in all countries. Approval has been granted for the treatment of more than 30 products with radiation in over 30 countries but, in general, governments have been slow to authorize the use of this new technique. One reason for this slowness is a lack of understanding of what food irradiation entails. This book aims to increase understanding by providing information on the process of food irradiation in simple, non-technical language. It describes the effects that irradiation has on food, and the plant and equipment that are necessary to carry it out safely. The legislation and control mechanisms required to ensure the safety of food irradiation facilities are also discussed. Education is seen as the key to gaining the confidence of the consumers in the safety of irradiated food, and to promoting understanding of the benefits that irradiation can provide. (orig.) With 4 figs., 1 tab [de

  10. Food irradiation: advantages and limitations

    International Nuclear Information System (INIS)

    Hernandes, N.K.; Vital, H. de C.; Sabaa-Srur, A.U.O.

    2003-01-01

    Food irradiation is a physical method of processing food (e.g. freezing, canning). It has been thoroughly researched over the last four decades and is recognized as a safe and wholesome method. It has the potential both of disinfesting dried food to reduce storage losses and disinfesting fruits and vegetables to meet quarantine requirements for export trade. Low doses of irradiation inhibit spoilage losses due to sprouting of root and tuber crops. Food- borne diseases due to contamination by pathogenic microorganisms and parasites of meat, poultry, fish, fishery products and spices are on the increase. Irradiation of these solid foods can decontaminate them of pathogenic organisms and thus provide safe food to the consumer. Irradiation can successfully replace the fumigation treatment of cocoa beans and coffee beans and disinfest dried fish, dates, dried fruits, etc. One of the most important advantages of food irradiation processing is that it is a coldprocess which does not significantly alter physico-chemical characters of the treated product. It can be applied to food after its final packaging. Similar to other physical processes of food processing, (e.g. canning, freezing), irradiation is a capital intensive process. Thus, adequate product volume must be made available in order to maximize the use of the facility and minimize the unit cost of treatment. Lack of harmonization of regulations among the countries which have approved irradiated foods hampers the introduction of this technique for international trade. Action at the international level has to be taken in order to remedy this situation. One of the important limitations of food irradiation processing is its slow acceptance by consumers, due inter alia to a perceived association with radioactivity. The food industry tends to be reluctant to use the technology in view of uncertainties regarding consumer acceptance of treated foods. Several market testing and consumer acceptance studies have been carried

  11. Nanocrystalline solids

    International Nuclear Information System (INIS)

    Gleiter, H.

    1991-01-01

    Nanocrystalline solids are polycrystals, the crystal size of which is a few (typically 1 to 10) nanometres so that 50% or more of the solid consists of incoherent interfaces between crystals of different orientations. Solids consisting primarily of internal interfaces represent a separate class of atomic structures because the atomic arrangement formed in the core of an interface is known to be an arrangement of minimum energy in the potential field of the two adjacent crystal lattices with different crystallographic orientations on either side of the boundary core. These boundary conditions result in atomic structures in the interfacial cores which cannot be formed elsewhere (e.g. in glasses or perfect crystals). Nanocrystalline solids are of interest for the following four reasons: (1) Nanocrystalline solids exhibit an atomic structure which differs from that of the two known solid states: the crystalline (with long-range order) and the glassy (with short-range order). (2) The properties of nanocrystalline solids differ (in some cases by several orders of magnitude) from those of glasses and/or crystals with the same chemical composition, which suggests that they may be utilized technologically in the future. (3) Nanocrystalline solids seem to permit the alloying of conventionally immiscible components. (4) If small (1 to 10 nm diameter) solid droplets with a glassy structure are consolidated (instead of small crystals), a new type of glass, called nanoglass, is obtained. Such glasses seem to differ structurally from conventional glasses. (orig.)

  12. Solid Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Supported by a generous quantity of full-color illustrations and interesting sidebars, Solid Matter introduces the basic characteristics and properties of solid matter. It briefly describes the cosmic connection of the elements, leading readers through several key events in human pre-history that resulted in more advanced uses of matter in the solid state. Chapters include:. -Solid Matter: An Initial Perspective. -Physical Behavior of Matter. -The Gravity of Matter. -Fundamentals of Materials Science. -Rocks and Minerals. -Metals. -Building Materials. -Carbon Earth's Most Versatile Element. -S

  13. 99mTc ovalbumin labelled eggs for gastric emptying scintigraphy: in-vitro comparison of solid food markers.

    Science.gov (United States)

    Blanc, Frédérique; Salaun, Pierre Y; Couturier, Olivier; Querellou, Solène; Le Duc-Pennec, Alexandra; Mougin-Degraef, Marie; Bizais, Yves; Legendre, Jean M

    2005-11-01

    The reliability of solid phase gastric emptying measurements by scintigraphy requires a marker that remains within the solid component of the test meal, and which is not degraded by the gastric juice throughout the scintigraphic procedure. In Europe, foods are most often labelled with 99mTc rhenium sulfide macrocolloid (RSMC) but this solid phase marker was withdrawn from the market in January 2004. To test other potential solid phase markers and to compare them to the reference marker RSMC. These markers were rhenium sulfide nanocolloid (RSNC), tin fluoride colloid (TFC), phytates and two albumins (Alb and AlbC). All were radiolabelled with 99mTc. After quality control, each 99mTc marker was incorporated into the albumin of one egg. Then, egg white and yolk were mixed together, and a well-cooked omelette was prepared. Aliquots of the omelette were incubated with an acidic solution of pepsin at 37 degrees C which mimicked gastric juice. Unbound radioactivity in the supernatant fraction was measured at various times up to 3 h. The radiochemical purity was > 95% for all radiopharmaceuticals. During the in-vitro incubation, the percentage of 99mTc labelled colloids released from the omelette increased continuously: after 3 h, 5% for TFC and RSMC, 8% for phytates, and > 9% for the two albumins and RSNC. Considering quality controls and release of 99mTc during in-vitro incubation of the omelette, TFC showed the same behaviour as the reference marker RSMC. Thus, TFC seems to be the best candidate to replace RSMC for the radiolabelling of the solid phase of the gastric emptying test meal.

  14. Irradiation device

    International Nuclear Information System (INIS)

    Suzuki, Toshimitsu.

    1989-01-01

    In an irradiation device for irradiating radiation rays such as electron beams to pharmaceuticals, etc., since the distribution of scanned electron rays was not monitored, the electron beam intensity could be determined only indirectly and irradiation reliability was not satisfactory. In view of the above, a plurality of monitor wires emitting secondary electrons are disposed in the scanning direction near a beam take-out window of a scanning duct, signals from the monitor wires are inputted into a display device such as a cathode ray tube, as well as signals from the monitor wires at the central portion are inputted into counting rate meters to measure the radiation dose as well. Since secondary electrons are emitted when electron beams pass through the monitor wires and the intensity thereof is in proportion with the intensity of incident electron beams, the distribution of the radiation dose can be monitored by measuring the intensity of the emitted secondary electrons. Further, uneven irradiation, etc. can also be monitored to make the radiation of irradiation rays reliable. (N.H.)

  15. Irradiation creep in simple binary alloys

    International Nuclear Information System (INIS)

    Nagakawa, J.; Sethi, V.K.; Turner, A.P.L.

    1981-07-01

    Creep enhancement during 21-MeV deuteron irradiation was examined at 350 0 C for two simple binary alloys with representative microstructures, i.e., solid-solution (Ni - 4 at. % Si) and precipitation-hardened (Ni - 12.8 at. % Al) alloys. Coherent precipitates were found to be very effective in suppressing irradiation-enhanced creep. Si solute atoms depressed irradiation creep moderately and caused irradiation hardening via radiation-induced segregation. The stress-dependence of irradiation creep in Ni - 4 at. % Si should a transition, which seems to reflect a change of mechanism from dislocation climb due to stress-induced preferential absorption (SIPA) to climb-controlled dislocation glide enhanced by irradiation

  16. Food irradiation

    International Nuclear Information System (INIS)

    Beishon, J.

    1991-01-01

    Food irradiation has been the subject of concern and controversy for many years. The advantages of food irradiation include the reduction or elimination of dangerous bacterial organisms, the control of pests and insects which destroy certain foods, the extension of the shelf-life of many products, for example fruit, and its ability to treat products such as seafood which may be eaten raw. It can also replace existing methods of treatment which are believed to have hazardous side-effects. However, after examining the evidence produced by the proponents of food irradiation, the author questions whether it has any major contribution to make to the problems of foodborne diseases or world food shortages. More acceptable solutions, he suggests, may be found in educating food handlers to ensure that hygienic conditions prevail in the production, storage and serving of food. (author)

  17. Vinca irradiator

    International Nuclear Information System (INIS)

    Eymery, R.

    1976-10-01

    The development programme of the VINCA radiosterilisation centre involves plans for an irradiator capable of working in several ways. Discontinuous operation. The irradiator is loaded for a certain period then runs automatically until the moment of unloading. This method is suitable as long as the treatment capacity is relatively small. Continuous operation with permanent batch loading and unloading carried out either manually or automatically (by means of equipment to be installed later). Otherwise the design of the apparatus is highly conventional. The source is a vertical panel submersible in a pool. The conveyor is of the 'bucket' type, with 4 tiers to each bucket. The batches pass successively through all possible irradiation positions. Transfert into and out of the cell take place through a maze, which also provides access to the cell when the sources are in storage at the bottom of the pool [fr

  18. Irradiance gradients

    International Nuclear Information System (INIS)

    Ward, G.J.; Heckbert, P.S.; Technische Hogeschool Delft

    1992-04-01

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

  19. Solid waste

    International Nuclear Information System (INIS)

    1995-01-01

    The article drawn up within the framework of 'the assessment of the state of the environment in Lebanon' provides an overview of solid waste management, and assesses future wastes volume and waste disposal issues.In particular it addresses the following concerns: - Long term projections of solid waste arisings (i.e. domestic, industrial, such commercial wastes, vehicle types, construction waste, waste oils, hazardous toxic wastes and finally hospital and clinical wastes) are described. - Appropriate disposal routes, and strategies for reducing volumes for final disposal - Balance between municipal and industrial solid waste generation and disposal/treatment and - environmental impacts (aesthetics, human health, natural environment )of existing dumps, and the potential impact of government plans for construction of solid waste facilities). Possible policies for institutional reform within the waste management sector are proposed. Tables provides estimations of generation rates and distribution of wastes in different regions of Lebanon. Laws related to solid waste management are summarized

  20. Food irradiation and its biological effects

    International Nuclear Information System (INIS)

    Shah, Alok; Nanjappa, C.; Chauhan, O.P.

    2014-01-01

    Irradiation of foods drew attention mostly in 1960s for disinfestation of food grains, spices and sprout inhibition in mainly potato and onion. γ-irradiation at 0.25 to 1 kGy dosage levels are usually used for irradiating grains, legumes, spices and sprout-prone vegetables. Irradiation of foods with in permissible dosage levels of 0.25 to 5 kGy is usually considered fairly safe from human consumption point of view not withstanding usual health concerns about its usage in foods. Irradiation of foods, in mostly solid or semi-solid form, at 5 kGy levels of γ-irradiation can achieve radicidation or, radiation equivalent of pasteurization and, if γ-irradiation is used at 10 kGy, it can achieve radappertization or, radiation equivalent of thermal commercial sterilization. However, the food industry uses γ-irradiation at 0.25 to 2 kGy only for mostly disinfestation of food grains/legumes, spices, sprout inhibition in potato and onion and, for surface sanitation of frozen fish, poultry and meat. Exposure to irradiation creates free radicals in foods that are capable of destroying some of the spoilage and pathogenic microflora but the same can also damage vitamins and enzymes besides creating some new harmful new chemical species, called unique radiolytic products (URPs), by combining with certain chemicals that a food may be laced with (like pesticides/fungicides). Exposure to high-energy electron beams are also known to create deleterious biological effects which may even lead to detection of trace amounts of radioactivity in the food. Some possible causes delineated for such harmful biological effects of irradiation include: irradiation induced vitamin deficiencies, the inactivity of enzymes in the foods, DNA damage and toxic radiolytic products in the foods. Irradiation, a non-thermal food preservation technique, has a role in salvaging enormous post harvest losses (25-30%) in developing economies to increase the per capita availability of foods. (author)

  1. Mutation induced with ion beam irradiation in rose

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, H. E-mail: yhiroya@nias.affrc.go.jp; Nagatomi, S.; Morishita, T.; Degi, K.; Tanaka, A.; Shikazono, N.; Hase, Y

    2003-05-01

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

  2. Radiation induced homogeneous precipitation in undersaturated solid-solutions

    International Nuclear Information System (INIS)

    Cauvin, Richard; Martin, Georges.

    1978-01-01

    The stability of various types of solid solutions under irradiation is studied. In this paper, observations made on AlZn solid solutions under 1 MeV electron irradiation are reported. Al-Zn was chosen as a prototype of solid solutions with a simple miscibility gap. It is shown that under appropriate irradiation conditions undersaturated AnZn solid solutions give rise to a homogeneous precipitation of coherent G.P. zones and of incoherent Zn precipitates the atomic volume of which is smaller than that of the matrix. We propose a more general treatment of solute concentration heterogeneities in solid solutions under irradiation and suggest how it might account for the nucleation of the observed phases. The growth of the observed precipitates is studied

  3. ion irradiation

    Indian Academy of Sciences (India)

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

  4. Fish irradiation

    International Nuclear Information System (INIS)

    Kovacs, J.; Tengumnuay, C.; Juangbhanich, C.

    1970-01-01

    Chub-mackerel was chosen for the study because they are the most common fish in Thailand. Preliminary investigations were conducted to determine the maximum radiation dose of gamma-rays by organoleptic tests. The samples were subjected to radiation at various doses up to 4 Mrad. Many experiments were conducted using other kinds of fish. The results showed that 1 Mrad would be the maximum acceptable dose for fish. Later, the influence of the radiation dose from 0.1-1 Mrad was studied in order to find the optimum acceptable dose for preservation of fish without off-flavour. For this purpose, the Hedonic scale was used. It was found that 0.2 and 0.5 Mrad gave the best result on Chub mackerel. The determinations of optimum dose, organoleptic, microbiological and trimethylamine content changes were done. The results showed that Chub mackerel irradiated at 0.2, 0.5 and 1 Mrad stored at 3 0 C for 71 days were still acceptable, on the contrary the untreated samples were found unacceptable at 14 days. The trimethylamine increment was significantly higher in the untreated samples. At 15 days storage, trimethylamine in the non-irradiated Chub-mackerel was about 10 times higher than the irradiated ones. At 51 and 79 days storage, about 13 times higher in the control samples than the irradiated samples except 0.1 Mrad. Only 2 times higher was found for the 0.1 Mrad. The microbiological results showed that the irradiation above 0.2 Mrad gave favorable extension of shelf-life of fish

  5. Chapter 2: Irradiators

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2018-04-01

    The chapter 2 presents the subjects: 1) gamma irradiators which includes: Category-I gamma irradiators (self-contained); Category-II gamma irradiators (panoramic and dry storage); Category-III gamma irradiators (self-contained in water); Category-IV gamma irradiators (panoramic and wet storage); source rack for Category-IV gamma irradiators; product transport system for Category-IV gamma irradiators; radiation shield for gamma irradiators; 2) accelerators which includes: Category-I Accelerators (shielded irradiator); Category-II Accelerators (irradiator inside a shielded room); Irradiation application examples.

  6. A Solid State Pyranometer

    Directory of Open Access Journals (Sweden)

    Dumitrescu Anca Laura

    2015-12-01

    Full Text Available The construction of a solid state device-based pyranometer designated to broadband irradiance measurements is presented in this paper. The device is built on the physical basis that the temperature difference between two bodies of identical shape and external surface area, identically exposed to the incident radiation, but having different absorption and heat transfer coefficients (e.g. one body is painted white and the other is painted black, is proportional to the incident irradiance. This proportionality may be put in evidence if the two bodies consisting of identical arrays of correspondingly painted semiconductor diodes, due to the thermal behaviour of their p-n junction. It is theoretically predicted and experimentally confirmed that the voltage drop across a diode passed through a constant forward current linearly decreases with the temperature of the junction. In other words, a signal proportional to the irradiance of the light source may be obtained via conventional analog electronics. The calibration of the apparatus, as performed by means of a professional device (LP PYRA 03, indicates a good linearity.

  7. A Solid State Pyranometer

    Science.gov (United States)

    Dumitrescu, Anca Laura; Paulescu, Marius; Ercuta, Aurel

    2015-12-01

    The construction of a solid state device-based pyranometer designated to broadband irradiance measurements is presented in this paper. The device is built on the physical basis that the temperature difference between two bodies of identical shape and external surface area, identically exposed to the incident radiation, but having different absorption and heat transfer coefficients (e.g. one body is painted white and the other is painted black), is proportional to the incident irradiance. This proportionality may be put in evidence if the two bodies consisting of identical arrays of correspondingly painted semiconductor diodes, due to the thermal behaviour of their p-n junction. It is theoretically predicted and experimentally confirmed that the voltage drop across a diode passed through a constant forward current linearly decreases with the temperature of the junction. In other words, a signal proportional to the irradiance of the light source may be obtained via conventional analog electronics. The calibration of the apparatus, as performed by means of a professional device (LP PYRA 03), indicates a good linearity.

  8. Detection of irradiated frozen foods

    International Nuclear Information System (INIS)

    Miyahara, Makoto; Toyoda, Masatake; Saito, Yukio

    1998-01-01

    We tried to detect whether foods were irradiated or not by the o-tyrosine method and the mtDNA method. The o-tyrosine method was applied to four kinds of meat (beef, pork, chicken and tuna). The results showed the linear relation between amount of o-tyrosine and dose (0-10 kGy). However, small amount of o-tyrosine were produced in some cases which application of the method summed to be very difficult because small difference between irradiated foods and untreated foods. Possibility of mtDNA method was investigated. Work and time for separation of mitochondria and extraction of DNA were reduced by a protease-solid phase extraction method. By PCR method, accurate mtDNA could be detected from very small amount of DNA. The irradiation effect is able to detect from 50 Gy. (S.Y.)

  9. Food irradiation: An update

    International Nuclear Information System (INIS)

    Morrison, Rosanna M.

    1984-01-01

    Recent regulatory and commercial activity regarding food irradiation is highlighted. The effects of irradiation, used to kill insects and microorganisms which cause food spoilage, are discussed. Special attention is given to the current regulatory status of food irradiation in the USA; proposed FDA regulation regarding the use of irradiation; pending irradiation legislation in the US Congress; and industrial applications of irradiation

  10. Industrial irradiation

    International Nuclear Information System (INIS)

    Stirling, Andrew

    1995-01-01

    Production lines for rubber gloves would not appear to have much in common with particle physics laboratories, but they both use accelerators. Electron beam irradiation is often used in industry to improve the quality of manufactured goods or to reduce production cost. Products range from computer disks, shrink packaging, tyres, cables, and plastics to hot water pipes. Some products, such as medical goods, cosmetics and certain foodstuffs, are sterilized in this way. In electron beam irradiation, electrons penetrate materials creating showers of low energy electrons. After many collisions these electrons have the correct energy to create chemically active sites. They may either break molecular bonds or activate a site which promotes a new chemical linkage. This industrial irradiation can be exploited in three ways: breaking down a biological molecule usually renders it useless and kills the organism; breaking an organic molecule can change its toxicity or function; and crosslinking a polymer can strengthen it. In addition to traditional gamma irradiation using isotopes, industrial irradiation uses three accelerator configurations, each type defining an energy range, and consequently the electron penetration depth. For energies up to 750 kV, the accelerator consists of a DC potential applied to a simple wire anode and the electrons extracted through a slot in a coaxially mounted cylindrical cathode. In the 1-5 MeV range, the Cockcroft-Walton or Dynamitron( R ) accelerators are normally used. To achieve the high potentials in these DC accelerators, insulating SF6 gas and large dimension vessels separate the anode and cathode; proprietary techniques distinguish the various commercial models available. Above 5 MeV, the size of DC accelerators render them impractical, and more compact radiofrequency-driven linear accelerators are used. Irradiation electron beams are actually 'sprayed' over the product using a magnetic deflection system. Lower energy beams of

  11. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Beerens, H [Lille-1 Univ., 59 - Villeneuve-d' Ascq (France); Saint-Lebe, L

    1979-01-01

    Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment.

  12. Irradiation device

    International Nuclear Information System (INIS)

    Ransohoff, J.A.

    1984-01-01

    Carriers, after being loaded with product to be irradiated, are transported by an input-output conveyor system into an irradiation chamber where they are received in a horizontal arrangement on racks which may support different sizes and numbers of carriers. The racks are moved by a chamber conveyor system in an endless rectangular path about a radiation source. Packers shift the carriers on the racks to maintain nearest proximity to the radiation source. The carriers are shifted in position on each rack during successive rack cycles to produce even radiation exposure. The carriers may be loaded singly onto successive racks during a first cycle of movement thereof about the source, with loading of additional carriers, and/or unloading of carriers, onto each rack occurring on subsequent rack cycles of movement

  13. Food irradiation

    International Nuclear Information System (INIS)

    Roberts, P.B.

    1997-01-01

    Food can be provided with extra beneficial properties by physical processing. These benefits include a reduced possibility of food poisoning, or an increased life of the food. We are familiar with pasteurisation of milk, drying of vegetables, and canning of fruit. These physical processes work because the food absorbs energy during treatment which brings about the changes needed. The energy absorbed in these examples is heat energy. Food irradiation is a less familiar process. It produces similar benefits to other processes and it can sometimes be applied with additional advantages over conventional processing. For example, because irradiation causes little heating, foods may look and taste more natural. Also, treatment can take place with the food in its final plastic wrappers, reducing the risk of re-contamination. (author). 1 ref., 4 figs., 1 tab

  14. Food irradiation

    International Nuclear Information System (INIS)

    Beerens, H.; Saint-Lebe, L.

    1979-01-01

    Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment [fr

  15. Endolymphatic irradiation

    International Nuclear Information System (INIS)

    Galvao, M.M.; Ianhez, L.E.; Sabbaga, E.

    1982-01-01

    The authors analysed the clinical evolution and the result of renal transplantation some years after irradiation in 24 patients (group I) who received endolymphatic 131 I as a pre-transplantation immunesuppresive measure. The control group (group II) consisted of 24 non-irradiated patients comparable to group I in age, sex, primary disease, type of donor and immunesuppressive therapy. Significant differences were observed between the two groups regarding such factors a incidence and reversibility of rejection crises in the first 60 post-transplantation days, loss of kidney due to rejection, and dosage of azathioprine. The authors conclude that this method, besides being harmless, has prolonged immunesuppressive action, its administration being advised for receptores of cadaver kidneys, mainly those who show positive cross-match against HLA antigens for painel. (Author) [pt

  16. Solid state and materials research

    International Nuclear Information System (INIS)

    1988-01-01

    Surface and sub-surface regions of solids are modified by rapid melting and quenching, using a high-powered, pulsed (30 ns) ruby laser. The main emphasis of this work is on laser annealing, epitaxy and doping of silicon. Computer programs have been developed to calculate the heat-flow which takes place during pulsed laser irradiation. From such calculations, information can be obtained about temperature profiles, melt depths, recrystallization velocities and quench rates. 13 figs., 9 refs., 1 tab

  17. Solute segregation during irradiation

    International Nuclear Information System (INIS)

    Wiedersich, H.; Okamoto, P.R.; Lam, N.Q.

    1977-01-01

    Irradiation at elevated temperature induces redistribution of the elements in alloys on a microstructural level. This phenomenon is caused by differences in the coupling of the various alloy constituents to the radiation-induced defect fluxes. A simple model of the segregation process based on coupled reaction-rate and diffusion equations is discussed. The model gives a good description of the experimentally observed consequences of radiation-induced segregation, including enrichment or depletion of solute elements near defect sinks such as surfaces, voids and dislocations; precipitation of second phases in solid solutions; precipitate redistribution in two-phase alloys; and effects of defect-production rates on void-swelling rates in alloys with minor solute additions

  18. Solid electrolytes

    Science.gov (United States)

    Abraham, Kuzhikalail M.; Alamgir, Mohamed

    1993-06-15

    This invention pertains to Li ion (Li.sup.+) conductive solid polymer electrolytes composed of solvates of Li salts immobilized (encapsulated) in a solid organic polymer matrix. In particular, this invention relates to solid polymer electrolytes derived by immobilizing complexes (solvates) formed between a Li salt such as LiAsF.sub.6, LiCF.sub.3 SO.sub.3 or LiClO.sub.4 and a mixture of aprotic organic solvents having high dielectric constants such as ethylene carbonate (EC) (dielectric constant=89.6) and propylene carbonate (PC) (dielectric constant=64.4) in a polymer matrix such as polyacrylonitrile, poly(tetraethylene glycol diacrylate), or poly(vinyl pyrrolidinone).

  19. Thermal conductivity of fusion solid breeder materials

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Tam, S.W.

    1986-06-01

    Several simple and useful formulae for estimating the thermal conductivity of lithium-containing ceramic tritium breeder materials for fusion reactor blankets are given. These formulae account for the effects of irradiation, as well as solid breeder configuration, i.e., monolith or a packed bed. In the latter case, a coated-sphere concept is found more attractive in incorporating beryllia (a neutron multiplier) into the blanket than a random mixture of solid breeder and beryllia spheres

  20. Structural investigation on gamma-irradiated polyacrylamide ...

    Indian Academy of Sciences (India)

    Polyacrylamide hydrogels; small-angle neutron scattering; UV–visible spectra; gamma ... dynamic light scattering and electron microscopy techniques and also by equilibrium swelling theory [10,11]. Here, for the first time, we report the effect of γ-irradiation on inhomogeneities and cor- ... The solid lines are guides to the eye.

  1. Sludge irradiation disinfection for beneficial use

    International Nuclear Information System (INIS)

    1980-12-01

    Papers given at the symposium are included in this volume. The symposium was organized to facilitate the transfer of information on the use of sludge irradiation as a process to further reduce pathogens. State-of-the-art gamma radiation of dried sewage solids is reviewed. Separate abstracts have been prepared for individual papers for inclusion in the Energy Data Base

  2. Cross-immunity among allogeneic tumors of rats immunized with solid tumors

    International Nuclear Information System (INIS)

    Ogasawara, Masamichi

    1979-01-01

    Several experiments were done for the study of cross-immunity among allogeneic rat tumors by immunization using gamma-irradiated or non-irradiated solid tumors. Each group of rats which were immunized with gamma-irradiation solid tumor inocula from ascites tumor cell line of tetra-ploid Hirosaki sarcoma, Usubuchi sarcoma or AH 130, showed an apparent resistance against the intraperitoneal challenge with Hirosaki sarcoma. A similar resistance was demonstrated in the case of the challenge with Usubuchi sarcoma into rats immunized with non-irradiated methylcholanthrene (MCA)-induced tumors. In using solid MCA tumors as immunogen and Hirosaki sarcoma as challenge tumor, it was also demonstrated in 2 out of 3 groups immunized with non-irradiated tumors. In the experiment of trying to induce cross-immunity between 2 MCA tumors by immunization with irradiated solid tumor only, the inhibitory effect on the growth was observed in the early stage in the treated groups as compared with the control one. From the above results, it may be considered that the immunization with irradiated solid tumors fromas cites cell lines and non-irradiated solid MCA tumors induced strong cross-immunity in general, but that the immunization with only irradiated solid MCA tumors induced weak cross-immunity commonly. (author)

  3. Biology of food irradiation

    International Nuclear Information System (INIS)

    Murray, D.R.

    1990-01-01

    The author presents his arguments for food scientists and biologists that the hazards of food irradiation outweigh the benefits. The subject is discussed in the following sections: introduction (units, mutagenesis, seed viability), history of food irradiation, effects of irradiation on organoleptic qualities of staple foods, radiolytic products and selective destruction of nutrients, production of microbial toxins in stored irradiated foods and loss of quality in wheat, deleterious consequences of eating irradiated foods, misrepresentation of the facts about food irradiation. (author)

  4. Postharvest quality of dragon fruit (Hylocereus spp.) after x-ray irradiation quarantine treatment

    Science.gov (United States)

    The quality of three dragon fruit clones (Hylocereus sp.) was determined following x-ray irradiation for disinfestation of quarantine pests. Fruit were treated with irradiation doses of 0, 200, 400, 600, or 800 Gy and stored for 12 days at 10 °C. Irradiation did not affect soluble solids content, ti...

  5. Effect of gamma irradiation on viscosity of aqueous solutions of some natural polymers

    International Nuclear Information System (INIS)

    Nguyen Tan Man; Truong Thi Hanh; Le Quang Luan; Le Hai; Nguyen Quoc Hien

    2000-01-01

    Effect of gamma irradiation on viscosity of aqueous solution of alginate and carbon xylmethyl cellulose (CMC) irradiated in solid state has been carried out. the viscosity of aqueous solution of alginate and CMC decreased remarkably with increasing dose and the viscosity of 2% solution of above polymers irradiated at 50 kGy was about 100 times lower than the original one. (author)

  6. Highly Perturbed pKa Values in the Unfolded State of Hen Egg White Lysozyme

    OpenAIRE

    Bradley, John; O'Meara, Fergal; Farrell, Damien; Nielsen, Jens Erik

    2012-01-01

    The majority of pKa values in protein unfolded states are close to the amino acid model pKa values, thus reflecting the weak intramolecular interactions present in the unfolded ensemble of most proteins. We have carried out thermal denaturation measurements on the WT and eight mutants of HEWL from pH 1.5 to pH 11.0 to examine the unfolded state pKa values and the pH dependence of protein stability for this enzyme. The availability of accurate pKa values for the folded state of HEWL and separa...

  7. A Colorimetric Analysis Experiment Not Requiring a Spectrophotometer: Quantitative Determination of Albumin in Powdered Egg White

    Science.gov (United States)

    Charlton, Amanda K.; Sevcik, Richard S.; Tucker, Dorie A.; Schultz, Linda D.

    2007-01-01

    A general science experiment for high school chemistry students might serve as an excellent review of the concepts of solution preparation, solubility, pH, and qualitative and quantitative analysis of a common food product. The students could learn to use safe laboratory techniques, collect and analyze data using proper scientific methodology and…

  8. Structural differences between native Hen egg white lysozyme and its fibrils under different environmental conditions

    Science.gov (United States)

    Bhattacharya, Susmita; Ghosh, Sudeshna; Dasgupta, Swagata; Roy, Anushree

    2013-10-01

    The difference in molecular structure of native HEWL and its fibrils, grown at a pH value near physiological pH 7.4 and at a pH value just above the pI, 10.7 in presence and absence of Cu(II) ions, is discussed. We focus on differences between the molecular structure of the native protein and fibrils using principal component analysis of their Raman spectra. The overlap areas of the scores of each species are used to quantify the difference in the structure of the native HEWL and fibrils in different environments. The overall molecular structures are significantly different for fibrils grown at two pH values. However, in presence of Cu(II) ions, the fibrils have similarities in their molecular structures at these pH environments. Spectral variation within each species, as obtained from the standard deviations of the scores in PCA plots, reveals the variability in the structure within a particular species.

  9. Fish and Egg white Diet In Non-Dialyzing In-Patients with Moderate ...

    African Journals Online (AJOL)

    Dietary management of chronic renal failure (CRF) is effective in delaying the progression to end stage renal failure and the need for dialysis. However, a full agreement on the type and optimal protein intake for patients with CRF has not been reached. This study compared the efficacy of low-protein diets obtained from a ...

  10. Thermal, mechanical, and moisture absorption properties of egg white protein bioplastics with natural rubber and glycerol.

    Science.gov (United States)

    Jones, Alexander; Zeller, Mark Ashton; Sharma, Suraj

    2013-07-03

    Petroleum-based plastics have many drawbacks: the large amount of energy required to produce the plastic, the waste generated as a result of plastic production, and the accumulation of waste due to slow degradation rate. It is because of these negative attributes of conventional plastic use that attention is being focused on environmentally friendly plastics from alternative sources. Albumin protein provides one possible source of raw material, with inherent antimicrobial properties that may make it suitable for medical applications. We conducted this study to investigate the various bioplastic properties of the albumin with the use of three plasticizers - water, glycerol, and natural rubber latex. Based on results, 75:25 albumin-water, 75:25 albumin-glycerol, and 80:20 albumin-natural rubber were the best blending ratios for each plasticizer for a subsequent time study to determine water stability, with the 80:20 albumin-natural rubber blend ratio having possessed the best thermal, tensile, and viscoelastic properties overall.

  11. Renaturation of reduced hen egg white lysozyme containing two blocked sulfhydryl groups

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, A.S.; Taniuchi, H.

    1980-10-01

    Formation of native lysozyme from the reduced form involves many pathways in two processes: incorrect pairing of half-cystine residues by oxidation and rearrangement of disulfide (SS) bonds. The energy barrier against suflhydryl (SH)-disulfide interchange of the native or nativelike species thus formed causes accumulation of these species. For example, the enzymatically active isomers containing three presumably native SS bonds and one open SS bond may be thermodynamically favorable over the nonnative isomers and can be formed from reduced lysozyme or lysozyme containing scrambled SS bonds by nonobligatory and flexible pathways. As an extension of these observations formation of nativelike species from reduced lysozyme containing the average of two carboxymethyl (CM)-cysteine was investigated.

  12. Evaluation of irradiated sewage sludges

    International Nuclear Information System (INIS)

    Colin C, A.

    1994-01-01

    The residual muds are produced by a separation process in the black waters treatment constituted by a solid phase whose origin is the accumulation of pollutant matter that has been extended to the water for anthropogenic and/or natural activities. The present work has the purpose to carry out a technical evaluation for the irradiation process of residual muds for their possible application like alternative of treatment and final disposal. The results obtained for the Evaluation of the irradiation of residual muds are bounded with the federative entities in the study, on the number of treatment plants of residual waters by diverse methods, discharge types, system location, residual muds production and muds treatment, uses and final disposal. The results show in the several entities,a great variety and versatility of industrial branches with diverse systems for treatment of waters and scarceness in the systems for residual muds treatment. (Author)

  13. Effect of gamma irradiation on microbiological, chemical and sensory characteristics of aniseed (anisum vulgare)

    International Nuclear Information System (INIS)

    Al-Bachir, M.

    2002-09-01

    Seeds of ansium were exposed to doses of 0, 5, 10, 15 and 20 kGy in a 60 Co package irradiator, Irradiated and unirradiated samples were stored at room temperature. Microbial population on seeds, dissolved organic and inorganic solids in extract and sensory properties of extract were evaluated after 0, 6 and 12 months of storage. The results indicated that gamma irradiation reduced the aerobic plate counts. Immediately after irradiation, the dissolved organic solids in extract of irradiated seeds were higher than those of non-irradiated ones. The dissolved organic matter in extract of irradiated and un-irradiated ansium seeds increased. After 6 and 12 months of storage. There were no significant differences in dissolved solids between the extract of irradiated and non-irradiated ansium seeds. Sensory evaluation indicated that gamma irradiation improved sensory characteristics of ansium seed extract tested immediately after irradiation; however, after 12 months of storage, no significant differences (P>0.05) were found in color, taste or odor between extract of irradiated and unirradiated ansium seeds. (author)

  14. Irradiation Facilities at CERN

    CERN Document Server

    Gkotse, Blerina; Carbonez, Pierre; Danzeca, Salvatore; Fabich, Adrian; Garcia, Alia, Ruben; Glaser, Maurice; Gorine, Georgi; Jaekel, Martin, Richard; Mateu,Suau, Isidre; Pezzullo, Giuseppe; Pozzi, Fabio; Ravotti, Federico; Silari, Marco; Tali, Maris

    2017-01-01

    CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

  15. Effect of irradiation on biochemistry properties of shrimp allergen

    International Nuclear Information System (INIS)

    Gu Kefei; Gao Meixu; Li Chunhong; Li Shurong; Pan Jiarong

    2007-01-01

    Study on the effects of 60 Co γ-rays irradiation at the dose of 0,3,5,7,10 kGy on shrimp allergen biochemistry properties was conducted. The results indicated that the allergen protein molecule can be broken down to smaller molecules or coagulated to larger molecules by irradiation. The hydrophobicity and turbidity of irradiated allergen increased with the increase of absorbed dose. The results also show that allergen solution is more sensitive to irradiation than allergen in solid state or in the whole shrimp. (authors)

  16. ESR investigataions of electron-beam irradiated cellulose nitrate

    International Nuclear Information System (INIS)

    Chipara, M.I.; Catana, D.; Grecu, V.; Romero, J.R.; Chipara, D.

    1994-01-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

  17. ESR investigataions of electron-beam irradiated cellulose nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Chipara, M.I.; Catana, D. [Institute of Atomic Physics, Bucharest (Romania); Grecu, V.; Romero, J.R. [Bucharest Univ. (Romania). Faculty of Physics; Coca, S. [Chemical Research Inst., Bucharest (Romania); Chipara, D. [Research Inst. for Electrotechnics, Bucharest (Romania)

    1994-10-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311) are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and its is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author).

  18. ESR investigations of electron-beam irradiated cellulose nitrate

    International Nuclear Information System (INIS)

    Chipara, M.I.; Grecu, V.; Catana, D.; Romero, J.R.; Coca, S.; Chipara, M.D.

    1994-01-01

    Electron spin resonance investigations on an electron-beam irradiated solid state nuclear track detector, based on cellulose nitrate (KODAK LR-311), are reported. The nature of free radicals induced in polymers by irradiation is discussed. The dependence of resonance spectral parameters on irradiation times, as well as on storage time and temperature, is studied. The experimental results are related to the stability of latent tracks and it is concluded that the free radicals induced by irradiation are located within the latent tracks. We have shown that both latent track and free radical thermal fading obey an Arrhenius-like dependence, with the same activation energy. (Author)

  19. Radiation damage of uranium-thorium oxide, irradiated in water

    International Nuclear Information System (INIS)

    Bloem, P.J.C.; Nagel, W.; Plas, T. van der; Kema, N.V.

    1977-01-01

    A suspension in water of spherical particles of UO 2 -ThO 2 with diameter 5μm has been considered as the working fluid in an aqueous, homogeneous, thermal nuclear reactor. Irradiation experiments have shown that these particles suffer a gradual breakdown when irradiated in water. This behaviour is markedly different from that shown on irradiation in absence of water. As damage was defined the amount of solid dissolved by an etching liquid. Electron microscopic pictures showed that at higher irradiation temperatures in water the actual damage was larger than the etching values indicated. (orig.) [de

  20. Perspective on food irradiation

    International Nuclear Information System (INIS)

    Newsome, R.L.

    1987-01-01

    A brief review summarizes current scientific information on the safety and efficacy of irradiation processing of foods. Attention is focused on: specifics of the irradiation process and its effectiveness in food preservation; the historical development of food irradiation technology in the US; the response of the Institute of Food Technologists to proposed FDA guidelines for food irradiation; the potential uses of irradiation in the US food industry; and the findings of the absence of toxins and of unaltered nutrient density (except possibly for fats) in irradiated foods. The misconceptions of consumers concerning perceived hazards associated with food irradiation, as related to consumer acceptance, also are addressed

  1. Effect of gamma irradiation on microbiological, chemical and sensory characteristics of aniseed (pimpinella anisum)

    International Nuclear Information System (INIS)

    Al-Bachir, M.

    2007-01-01

    Seeds of anise (pimpinella anisum) were exposed to doses of 0, 5, 10, 15 and 20 kGy in a 60 Co package irradiator. Irradiated and unirradiated samples were stored at room temperature. Microbial population on seeds, total and inorganic soluble solids in water extract and sensory properties of the latter were evaluated after 0, 6 and 12 months of storage. The results indicated that gamma irradiation reduced the aerobic plate counts of aniseed. Immediately after irradiation, the total soluble solids in an extract of irradiated seeds were greater than those of unirradiated ones. The total soluble solids in an extract of irradiated and un-irradiated seeds increased after 6 and 12 months of storage. There were no significant differences (p>0.05) in inorganic soluble solids between the water extract of irradiated and unirradiated aniseeds. Sensory evaluation indicated that gamma irradiation improved sensory characteristics of aniseed water extract tested immediately after irradiation. However, after 12 months of storage, no significant differences (P>0.05) were found in color, taste or flavor between extract of irradiated and unirradiated seeds. (author)

  2. Analysis of volatiles from irradiated yeast extract

    International Nuclear Information System (INIS)

    Liao Tao; Li Xin; Zu Xiaoyan; Chen Yuxia; Geng Shengrong

    2013-01-01

    The method for determination volatiles from irradiated yeast extract (YE) using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was developed in this paper. The extraction conditions were optimized with reference to the peak area and number of volatiles as aldehyde, ketone, alcohol, acid, ester and sulfur compounds. The optimized conditions of HS-SPME for volatiles in irradiated YE were: divinyl benzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber, extration time 40 min, extraction temperature 40℃. The volatiles from YE irradiated by 0-19.8 kGy were detected using HS-SPME coupled with GC-MS. The results showed that only 15 volatiles were detected from no irradiated YE and main compounds were acetic acid, 2, 3-butanediol and 1-hexanol, 2-ethyl-. There were 40 volatiles detected from irradiated YE and the main compounds were acetic acid, phenylethyl alcohol, heptanal and nonanal. Compare to no irradiated yeast extract, the aldehyde, ketone, alkene and disulfide, dimethyl were produced by irradiating process. (authors)

  3. Beneficial uses of nuclear byproducts/sewage sludge irradiation project. Progress report, October 1982-March 1983

    International Nuclear Information System (INIS)

    Pierce, J.D.

    1984-11-01

    Gamma irradiation of various commodities in the Sandia Irradiator for Dried Sewage Solids (SIDSS) and the Gamma Irradiation Facility (GIF) continued during this reporting period. One truck-load of grapefruit was irradiated. Pelletized straw was irradiated to doses of 1, 5, 10, 20, and 40 megarads in SIDSS. Sludge, virus, and fungus samples were irradiated. Infected ground pork and infected pig carcasses were irradiated in the GIF as a method of Trichinella spiralis inactivation. Other experiments conducted in the GIF included irradiation of cut flowers to extend their shelf life and irradiation of kepone to induce its degradation. Waste Encapsulation and Storage Facility (WESF) capsule studies at ORNL and SNLA continued. A purchase order was placed for a prototype sludge solar dryer. Sewage Sludge Irradiation Transportation System (SSITS) cask activities included thermal stress analyses of cask performance following separation from the impact limiters during a fire. Analyses of cask performance, when loaded with six strontium-90 (Sr-90) capsules, also were done

  4. Chemical structure and radiation stability of solid crystalline antibiotics: thiamphenicol and chloramphenicol

    International Nuclear Information System (INIS)

    Varshney, Lalit; Soe Nwe

    1997-01-01

    Antibiotics in solid state show significant radiation resistance and some of them are exposed to gamma or electron beam irradiation for sterilization. Even small radiation degradation in solid state antibiotics is not desirable. Two antibiotics namely thiamphenicol (TPL) and chloramphenicol (CPL) having similar chemical and solid state structure were irradiated at different graded radiation doses to study their stability. Differential scanning calorimetry (DSC) was used to evaluate purity, entropy of radiation processing, heat of fusion and melting point. (author). 3 refs., 1 tab

  5. Gamma sterilization of cefotaxime sodium in the solid state

    International Nuclear Information System (INIS)

    Kattan, M.; Aladawi, M. A.; Hammoudeh, A.; Albaroudi, H.

    2010-08-01

    To investigate the effect of gamma irradiation on the solid state of Cefotaxime sodium salt (C 1 8H 1 6N 8 Na 2 O 7 S 3 ) as a member of the third generation of cephalosporin. Solid Cefotaxime as a pharmaceutical dosage was exposed to doses of 0, 5, 10, 15, 20, 25, and 50 kGy in 60 Co package irradiator. Physical and chemical characteristics of Cefotaxime sodium have been investigated by using UV (Ultra Violet) and IR (Infra Red) spectroscopic, pH, solubility and DSC (Deferential Scanning Calorimetric) methods. The biological activity of Cefotaxime sodium was investigated using Escherichia coli ATCC 25922 as a strain of bacteria. The obtained results indicated that gamma irradiation have no effect on physical and chemical characteristics of Cefotaxime sodium, No significant differences were found between irradiated and non-irradiated samples in the biological activity of Cefotaxime sodium on E. Coli. (Author)

  6. Effect of irradiation and cold storage on the physiological characteristics of the pear fruits

    International Nuclear Information System (INIS)

    Mahmoud, A.A.; Roushdy, H.M.; El-Latif, F.A.; Taha, F.

    1988-01-01

    With the aim of extending shelf life of fruits and the effects of gamma irradiation at the 0, 1, 2, 3 and 4 KGy dose levels, the present investigation has been undertaken to illustrate, the possible application of gamma irradiation processing to prolong the storage period of mature pear fruit. Significant differences had been found between irradiated and non-irradiated fruits regarding total soluble solids, weight loss, decay, firmness, titrable acidity and moisture content

  7. FFTF disposable solid waste cask

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, J. D.; Goetsch, S. D.

    1983-01-01

    Disposal of radioactive waste from the Fast Flux Test Facility (FFTF) will utilize a Disposable Solid Waste Cask (DSWC) for the transport and burial of irradiated stainless steel and inconel materials. Retrievability coupled with the desire for minimal facilities and labor costs at the disposal site identified the need for the DSWC. Design requirements for this system were patterned after Type B packages as outlined in 10 CFR 71 with a few exceptions based on site and payload requirements. A summary of the design basis, supporting analytical methods and fabrication practices developed to deploy the DSWC is provided in this paper.

  8. FFTF disposable solid waste cask

    International Nuclear Information System (INIS)

    Thomson, J.D.; Goetsch, S.D.

    1983-01-01

    Disposal of radioactive waste from the Fast Flux Test Facility (FFTF) will utilize a Disposable Solid Waste Cask (DSWC) for the transport and burial of irradiated stainless steel and inconel materials. Retrievability coupled with the desire for minimal facilities and labor costs at the disposal site identified the need for the DSWC. Design requirements for this system were patterned after Type B packages as outlined in 10 CFR 71 with a few exceptions based on site and payload requirements. A summary of the design basis, supporting analytical methods and fabrication practices developed to deploy the DSWC is provided in this paper

  9. Solid residues

    International Nuclear Information System (INIS)

    Mulder, E.; Duin, P.J. van; Grootenboer, G.J.

    1995-01-01

    A summary is presented of the many investigations that have been done on solid residues of atmospheric fluid bed combustion (AFBC). These residues are bed ash, cyclone ash and bag filter ash. Physical and chemical properties are discussed and then the various uses of residues (in fillers, bricks, gravel, and for recovery of aluminium) are summarised. Toxicological properties of fly ash and stack ash are discussed as are risks of pneumoconiosis for workers handling fly ash, and contamination of water by ashes. On the basis of present information it is concluded that risks to public health from exposure to emissions of coal fly ash from AFBC appear small or negligible as are health risk to workers in the coal fly ash processing industry. 35 refs., 5 figs., 12 tabs

  10. Irradiation damage 'displacement zone'; Dommages sous irradiation zone de deplacements

    Energy Technology Data Exchange (ETDEWEB)

    Genthon, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    It is well known that a charged particle (ion, primary atom, etc...) moving in a solid slows down and can cause a cascade of displacements of the atoms in the solid. A study is made here of the extent to which the cascade is made up, or not, of independent collisions, as a function of the energy of the initial charged particle. When the distance between the collisions is small, these latter are no longer independent; the cascade, which then has to be considered as a whole, perturbs and locates, in the irradiated solid , a zone which has been named a 'displacement zone'. It is shown that the proportion of displacement zones increases with increasing atom size (high atomic number Z), with decreasing atomic distance D in the substance considered and with decreasing energy of the ion undergoing the slowing down process (although always remaining above a few hundred eV). The proportions obtained are higher than those corresponding to the calculations of J. A. Brinkman [3]. An interatomic potential required for this work has also been determined. (author) [French] On sait qu'une particule chargee (ions, atomes primaires, etc...) en mouvement dans un solide se ralentit, avec eventuellement deplacement en cascade d'atomes du solide. On etudie ici dans quelle proportion, en fonction de l'energie de la particule chargee initiale, la cascade est constituee, ou non, de 'chocs independants'. Lorsque la distance entre chocs est petite, ceux-ci ne sont plus independants; la cascade, qui doit alors etre consideree dans son ensemble, perturbe et definit dans le solide irradie, une zone qu'on a appele zone de deplacements. On montre que la proportion de zones de deplacements est d'autant plus grande que les atomes sont gros (nombre atomique Z grand), que la distance interatomique D est petite dans le corps considere, et que l'energie de l'ion en ralentissement est petite (tout en restant superieure a quelques centaines d'eV). Les proportions obtenues sont superieures a celles qui

  11. Effect of gamma irradiation on quality of kiwifruit (Actinidia deliciosa var. deliciosa cv. Hayward)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung-Hee [Department of Food and Nutrition, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Yook, Hong-Sun [Department of Food and Nutrition, Chungnam National University, Daejeon 305-764 (Korea, Republic of)], E-mail: yhsuny@cnu.ac.kr

    2009-06-15

    Ionizing radiation is able to inactivate the three pathogens of Botrytis cinerea, Diaporthe actinidiae, and Botryosphaeria dothidea in kiwifruit. Irradiated kiwifruits appeared softer compared to non-irradiated kiwifruits. The color and organic acid content of kiwifruits were minimally affected by the irradiation. Irradiated fruits showed a decrease in the total soluble solids content with increasing irradiation dose. Irradiation of kiwifruit up to 3 kGy had negative effects on vitamin C content and antioxidant activity, but it contributed to improving sensory quality.

  12. Relaxation and excitation electronic processes in dielectrics irradiated by ultrafast IR and VUV pulses; Processus electroniques d'excitation et de relaxation dans les solides dielectriques excites par des impulsions IR et XUV ultracourtes

    Energy Technology Data Exchange (ETDEWEB)

    Gaudin, J

    2005-11-15

    We studied excitation and relaxation of electrons involved during interaction of visible and VUV femtosecond pulses with dielectrics. The generated population of hot electrons, having energy of few eV to few tens of eV above the bottom of the conduction band, is responsible of phenomena ranging to defect creation to optical breakdown. Owing to two techniques: photoemission and transient photoconductivity we improve the understanding of the The first photoemission experiments deal with dielectrics irradiated by 30 fs IR pulses. The photoemission spectra measured show a large population of electrons which energy rise up to 40 eV. We interpret this result in terms of a new absorption process: direct multi-photons inter-branch transitions. The 2. type of photoemission experiments are time resolved 'pump/probe' investigation. We study the relaxation of electrons excited by a VUV pulses. We used the high order harmonics (HOH) as light sources. We found surprisingly long decay time in the range of ps timescale. Last type of experiments is photoconductivity studies of diamond samples. Using HOH as light source we measure the displacement current induced by excited electrons in the conduction band. Those electrons relax mainly by impact ionisation creating secondary electrons. Hence by probing the number of electrons we were able to measure the efficiency of these relaxation processes. We observe a diminution of this efficiency when the energy of exciting photons is above 20 eV. Owing to Monte-Carlo simulation we interpret this result in terms of band structure effect. (author)

  13. Characterization of a multi-keV x-ray source produced by nanosecond laser irradiation of a solid target: The influence of laser focus spot and target thickness

    International Nuclear Information System (INIS)

    Hu Guangyue; Zheng Jian; Shen Baifei; Lei Anle; Xu Zhizhan; Liu Shenye; Zhang Jiyan; Yang Jiamin; Ding Yongkun; Hu Xin; Huang Yixiang; Du Huabing; Yi Rongqing

    2008-01-01

    The influence of focus spot and target thickness on multi-keV x-ray sources generated by 2 ns duration laser heated solid targets are investigated on the Shenguang II laser facility. In the case of thick-foil targets, the experimental data and theoretical analysis show that the emission volume of the x-ray sources is sensitive to the laser focus spot and proportional to the 3 power of the focus spot size. The steady x-ray flux is proportional to the 5/3 power of the focus spot size of the given laser beam in our experimental condition. In the case of thin-foil targets, experimental data show that there is an optimal foil thickness corresponding to the given laser parameters. With the given laser beam, the optimal thin-foil thickness is proportional to the -2/3 power of the focus spot size, and the optimal x-ray energy of thin foil is independent of focus spot size

  14. Electron beam irradiating device

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, K

    1969-12-20

    The efficiency of an electron beam irradiating device is heightened by improving the irradiation atmosphere and the method of cooling the irradiation window. An irradiation chamber one side of which incorporates the irradiation windows provided at the lower end of the scanner is surrounded by a suitable cooling system such as a coolant piping network so as to cool the interior of the chamber which is provided with circulating means at each corner to circulate and thus cool an inert gas charged therewithin. The inert gas, chosen from a group of such gases which will not deleteriously react with the irradiating equipment, forms a flowing stream across the irradiation window to effect its cooling and does not contaminate the vacuum exhaust system or oxidize the filament when penetrating the equipment through any holes which the foil at the irradiation window may incur during the irradiating procedure.

  15. Suppression of Zn stress on barley by irradiated chitosan

    Energy Technology Data Exchange (ETDEWEB)

    Nagasawa, N.; Mitomo, H. [Gunma Univ., Faculty of Engineering, Department of Biological and Chemical Engineering, Kiryu, Gunma (Japan); Ha, P.T.L. [Nuclear Research Institute, Dalat (Viet Nam); Watanabe, S.; Ito, T.; Takeshita, H.; Yoshii, F.; Kume, T. [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    Chitosan was irradiated up to 1000 kGy in solid state. Irradiation of chitosan caused the reduction of molecular weight. The molecular weight of the chitosan reduced from ca. 4 x 10{sup 5} to ca. 6 x 10{sup 3} by irradiation at 1000 kGy. For the barley growth promotion, irradiated chitosan showed the significant effect and 1000 kGy irradiated chitosan improved 20% of growth. Using the positron emitting tracer imaging system (PETIS), the effect of chitosan on uptake and transportation of {sup 62}Zn in barley were investigated. It was found that the transportation of Zn from root to shoot and the damage of plant by Zn were suppressed with irradiated chitosan. (author)

  16. Suppression of Zn stress on barley by irradiated chitosan

    International Nuclear Information System (INIS)

    Nagasawa, N.; Mitomo, H.; Ha, P.T.L.; Watanabe, S.; Ito, T.; Takeshita, H.; Yoshii, F.; Kume, T.

    2001-01-01

    Chitosan was irradiated up to 1000 kGy in solid state. Irradiation of chitosan caused the reduction of molecular weight. The molecular weight of the chitosan reduced from ca. 4 x 10 5 to ca. 6 x 10 3 by irradiation at 1000 kGy. For the barley growth promotion, irradiated chitosan showed the significant effect and 1000 kGy irradiated chitosan improved 20% of growth. Using the positron emitting tracer imaging system (PETIS), the effect of chitosan on uptake and transportation of 62 Zn in barley were investigated. It was found that the transportation of Zn from root to shoot and the damage of plant by Zn were suppressed with irradiated chitosan. (author)

  17. Effect of gamma irradiation on storability of strawberry (Fragaria sp)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Bachir, M; Farah, S [Atomic Energy Commission, Dept. of Agriculture, Damascus (Syrian Arab Republic)

    1998-02-01

    Despite the increased production of strawberry in Syria, the storability and marketability of fruits were not well studied. The objectives of this study were to investigate the effect of gamma irradiation on storability of Senga sengana strawberry produced in Syria and the effect of gamma irradiation on fungal sp. i.e. Botrytis; Penicillium; Rhizopus. The fruits were treated with 1 , 2 and 3 KGy of gamma rays. Treated and untreated fruits were stored at 2 to 4 centigrade and 80 to 90 % relative humidity (RH). In order to investigate their marketability, the fruits where held at room temperature (25 to 30 centigrade). Weight loss, microbial decay, and total loss, juice production, pH, total soluble solids of the juice and organoleptic qualities were evaluated throughout the different storage and marketing periods. The results indicate that gamma irradiation decreased the microbial decay and increased the storability and marketability of fruits by 50 and 100% after using 2 and 3 kGy, respectively. D10 were 1.8 and 2.4 for Botrytis and Rhizopus respectively. One day after irradiation total soluble solids and its pH values were increased. Fourteen days later, irradiated fruits produced more juice with higher pH, but total soluble solids were less. Gamma irradiation did not have an effect on aroma and colour of fruits, whereas, 3 kGy of gamma irradiation had an adverse negative effect on taste. (author)

  18. Irradiation of goods

    International Nuclear Information System (INIS)

    Huebner, G.

    1992-01-01

    The necessary dose and the dosage limits to be observed depend on the kind of product and the purpose of irradiation. Product density and density distribution, product dimensions, but also packaging, transport and storage conditions are specific parameters influencing the conditions of irradiation. The kind of irradiation plant - electron accelerator or gamma plant - , its capacity, transport system and geometric arrangement of the radiation field are factors influencing the irradiation conditions as well. This is exemplified by the irradiation of 3 different products, onions, deep-frozen chicken and high-protein feed. Feasibilities and limits of the irradiation technology are demonstrated. (orig.) [de

  19. Biological responses of human solid tumor cells to X-ray irradiation within a 1.5-Tesla magnetic field generated by a magnetic resonance imaging-linear accelerator.

    Science.gov (United States)

    Wang, Li; Hoogcarspel, Stan Jelle; Wen, Zhifei; van Vulpen, Marco; Molkentine, David P; Kok, Jan; Lin, Steven H; Broekhuizen, Roel; Ang, Kie-Kian; Bovenschen, Niels; Raaymakers, Bas W; Frank, Steven J

    2016-10-01

    Devices that combine magnetic resonance imaging with linear accelerators (MRL) represent a novel tool for MR-guided radiotherapy. However, whether magnetic fields (MFs) generated by these devices affect the radiosensitivity of tumors is unknown. We investigated the influence of a 1.5-T MF on cell viability and radioresponse of human solid tumors. Human head/neck cancer and lung cancer cells were exposed to single or fractionated 6-MV X-ray radiation; effects of the MF on cell viability were determined by cell plating efficiency and on radioresponsiveness by clonogenic cell survival. Doses needed to reduce the fraction of surviving cells to 37% of the initial value (D0s) were calculated for multiple exposures to MF and radiation. Results were analyzed using Student's t-tests. Cell viability was no different after single or multiple exposures to MRL than after exposure to a conventional linear accelerator (Linac, without MR-generated MF) in 12 of 15 experiments (all P > 0.05). Single or multiple exposures to MF had no influence on cell radioresponse (all P > 0.05). Cells treated up to four times with an MRL or a Linac further showed no changes in D0s with MF versus without MF (all P > 0.05). In conclusion, MF within the MRL does not seem to affect in vitro tumor radioresponsiveness as compared with a conventional Linac. Bioelectromagnetics. 37:471-480, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Facts about food irradiation: Food irradiation costs

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet gives the cost of a typical food irradiation facility (US $1 million to US $3 million) and of the food irradiation process (US $10-15 per tonne for low-dose applications; US $100-250 per tonne for high-dose applications). These treatments also bring consumer benefits in terms of availability, storage life and improved hygiene. 2 refs

  1. Technological quality of irradiated Moroccan citrus fruits

    International Nuclear Information System (INIS)

    Moussaid El Idrissi, M.; R'Kiek, C.; Farahat Laaroussi, S.; Zantar; Mouhib, M.; El Guerrouj, D.; Toukour, L.

    2002-01-01

    The effect of irradiation at doses of 125, 250, 375, and 500 Gy, commonly used for quarantine treatment, on the quality of Maroc-late orange, the most common export variety of Morocco was investigated. In the first study fruits were irradiated without any previous cold conditioning treatment as practiced by the export trade for quarantine purposes. In the second study fruits obtained from the normal chain after conditioning was irradiated. Storage of irradiated fruits was studied at room temperature and 10 deg. C at 0 deg. C in case of control fruits. The parameters studied included juice yield, total solids, reducing and total sugars, total acids and volatile acids, dry weight and weight loss. The results showed that irradiation did not affect the technological quality of citrus fruits during four weeks storage. The result thus far points to the possibility for the successful application of irradiation as an alternative quarantine treatment to the classical methods, which result in browning of the peel. The browning phenomenon could be controlled by waxing and will be the subject of a future study. (author)

  2. Food irradiation in China

    International Nuclear Information System (INIS)

    Zhu Jiang

    1994-01-01

    In this paper, the author discussed the recent situation of food irradiation in China, its history, facilities, clearance, commercialization, and with emphasis on market testing and public acceptance of irradiated food. (author)

  3. Dosimetry for Crystals Irradiation

    CERN Document Server

    Lecomte, Pierre

    2005-01-01

    Before shipment to CMS, all PbWO4 crystals produced in China are irradiated there with 60 Co , in order to insure that the induced absorption coefficient is within specifications. Acceptance tests at CERNand at ENEA also include irradiation with gamma rays from 60 Co sources. There were initially discrepancies in quoted doses and doserates as well as in induced absorption coefficients. The present work resolves the discrepancies in irradiation measurements and defines common dosimetry methods for consistency checks between irradiation facilities.

  4. Irradiation and flavor

    International Nuclear Information System (INIS)

    Reineccius, G.A.

    1992-01-01

    Flavor will not be a significant factor in determining the success of irradiated foods entering the U.S. market. The initial applications will use low levels of irradiation that may well result in products with flavor superior to that of products from alternative processing techniques (thermal treatment or chemical fumigation). The success of shelf-stable foods produced via irradiation may be much more dependent upon our ability to deal with the flavor aspects of high levels of irradiation

  5. Food irradiation makes progress

    International Nuclear Information System (INIS)

    Kooij, J. van

    1984-01-01

    In the past fifteen years, food irradiation processing policies and programmes have been developed both by a number of individual countries, and through projects supported by FAO, IAEA and WHO. These aim at achieving general acceptance and practical implementation of food irradiation through rigorous investigations of its wholesomeness, technological and economic feasibility, and efforts to achieve the unimpeded movement of irradiated foods in international trade. Food irradiation processing has many uses

  6. Statics of deformable solids

    CERN Document Server

    Bisplinghoff, Raymond L; Pian, Theodore HH

    2014-01-01

    Profusely illustrated exposition of fundamentals of solid mechanics and principles of mechanics, statics, and simple statically indeterminate systems. Covers strain and stress in three-dimensional solids, elementary elasticity, energy principles in solid continuum, and more. 1965 edition.

  7. Containers in food irradiation

    International Nuclear Information System (INIS)

    Bolumen, S.; Espinosa, R.

    1997-01-01

    The preservation of food by irradiation is promising technology which increases industrial application. Packaging of irradiated foods is an integral part of the process. Judicious selection of the package material for successful trade is essential. In this paper is presented a brief review of important aspects of packaging in food irradiation [es

  8. Irradiation softening in pure iron single crystals

    International Nuclear Information System (INIS)

    Meshii, M.

    1975-01-01

    The characteristics of irradiation softening in Fe were studied. Results show that irradiation softening effect can be explained by the intrinsic mechanism, namely, the interaction of screw dislocations with randomly dispersed interstitials. At least some of the solid solution softening phenomena observed in alloys can be explained by the same mechanism. However, the alloying may be accompanied by an additional effect such as solute segregation to dislocations which may also strongly affect the yield stress. This effect may mask the softening effect partially or totally. Changes in the dislocation structure of deformed specimens caused by alloying, which are often reported in electron microscopic investigations, support this contention. The alloying, therefore, may not be as good as the low temperature irradiation in studying the effect of random solutes on dislocation motion and yield stress

  9. Theoretical solid state physics

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Research activities at ORNL in theoretical solid state physics are described. Topics covered include: surface studies; particle-solid interactions; electronic and magnetic properties; and lattice dynamics

  10. Improving Quality of Yoghurt By Irradiation

    International Nuclear Information System (INIS)

    Sallam, E.M.; Nasr, E.H.; Shawki, H.A.

    2012-01-01

    This investigation was carried out to study the possibility to utilize gamma irradiation to activate starter culture during incubation period and prolong the shelf-life of yoghurt. Starter culture of yoghurt was subjected to gamma irradiation with 10, 15, 20, 25, 30, 35, 40 and 45 Gy to activate the starter then yoghurt was made. Effect of irradiation dose on titratable acidity and the sensory evaluation of all samples were evaluated during incubation period. The obtained results indicated that the irradiation doses 30, 35 and 40 Gy activated the starter and caused significant decreased of incubation period from 4 h to 3.5 h while irradiation doses that less than 30 Gy and more than 40 Gy did not significantly effect. Yoghurt samples were subjected to gamma irradiation with 1.5, 2.5 and 3.5 kGy to prolong the shelf-life of yoghurt samples. The sensory, microbial and chemical properties of yoghurt samples were evaluated during cold storage. The obtained results indicated that the counts of total viable bacteria, molds and yeasts were decreased by applying gamma irradiation. Irradiation treatment caused significant decrease in acidity. The overall acceptability scores, total solid and ph value of all treatments were gradually decreased as the storage period proceeded while total nitrogen of all treatments was not affected. In addition, treatments of yoghurt with 1.5, 2.5 and 3.5 kGy prolonged the shelf-life to 20, 28 and 36 days as compared to 12 days for control treatment

  11. Irradiation-induced precipitation in Ni--Si alloys

    International Nuclear Information System (INIS)

    Barbu, A.; Ardell, A.J.

    1975-07-01

    The microstructures of Ni + ion-irradiated Ni--Si solid-solution alloys, containing 2, 4, 6 and 8 at. percent Si were investigated as a function of dose, dose-rate, and temperature. Results of transmission electron microscopy and other data show the precipitation of γ' (Ni 3 Si) in all samples irradiated at 500 0 C. Characteristics of the precipitates are described and a mechanism for their formation is suggested. (U.S.)

  12. Irradiation of foodstuffs

    International Nuclear Information System (INIS)

    Sjoeberg, A.M.

    1993-01-01

    Foodstuffs are irradiated to make them keep better. The ionizing radiation is not so strong as to cause radioactivity in the foodstuffs. At least so far, irradiation has not gained acceptance among consumers, although it has been shown to be a completely safe method of preservation. Irradiation causes only slight chemical changes in food. What irradiation does, however, is to damage living organisms, such as bacteria, DNA and proteins, thereby making the food keep longer. Irradiation can be detected from the food afterwards; thus it can be controlled effectively. (orig.)

  13. Thermally stimulated exoelectron emission from solid Xe

    International Nuclear Information System (INIS)

    Khyzhniy, I.V.; Grigorashchenko, O.N.; Savchenko, E.V.; Ponomarev, A.N.; Bondybey, V.E.

    2007-01-01

    Thermally-stimulated emission of exoelectrons and photons from solid Xe pre-irradiated by low-energy electrons were studied. A high sensitivity of thermally-stimulated luminescence (TSL) and thermally-stimulated exoelectron emission (TSEE) to sample prehistory was demonstrated. It was shown that electron traps in unannealed samples are characterized by much broader distribution of trap levels in comparison with annealed samples and their concentration exceeds in number that in annealed samples. Both phenomena, TSL and TSEE, were found to be triggered by release of electrons from the same kind of traps. The data obtained suggest a competition between two relaxation channels: charge recombination and electron transport terminated by TSL and TSEE. It was found that TSEE predominates at low temperatures while at higher temperatures TSL prevails. An additional relaxation channel, a photon-stimulated exoelectron emission pre-irradiated solid Xe, was revealed

  14. ???????????? SolidWorks/SolidWorks Flow Simulation/SolidWorks Simulation ??? ?????????? ???????? ?? ????????????? ???

    OpenAIRE

    ????????????, ?. ?.; ????????, ?. ?.; ?????, ?. ?.

    2012-01-01

    ? ?????? ???????? ??????? ??????? ???????? ?? ???????????? ??????????? ????????? SolidWorks/SolidWorks Flow Simulation (COSMOSFloWorks)/SolidWorks Simulation ??? ?????????? ???????? ?? ????????????? ???. ??? ???????? ????????? ???????? ?????????? ?? ?????? ???????? ??????? ? ????????????? ?????? ? ????????????? ????????????? ?????????? ???????????? SolidWorks Flow Simulation (COSMOSFloWorks). ??? ???????????? ??????????? ????????????? ?????? ?? ????????? ??????????? ??????? ?? ??????????? ...

  15. Thermogravimetric study of γ-irradiated lanthanum oxalate

    International Nuclear Information System (INIS)

    Nayak, H.; Bhatta, D.

    2000-01-01

    Thermogravimetric study of La 2 (C 2 O 4 ) 3 , exposed to different doses (5.0 - 50.0 x 10 -2 MGy) of γ-rays has been carried out. Marginal effect is observed at lower doses which is prominent at higher dose (5.0 x 10 -1 MGy). The radiolytic damaged entities, generated by irradiation favours the reaction by creating new potential nucleation centres in the lattice. The solid product, La 2 O 3 formed by irradiation also acts as a heterogeneous catalyst and brings out changes in the reactivity of the solid. (author)

  16. Cancer following medical irradiation

    International Nuclear Information System (INIS)

    Boice, J.D.

    1981-01-01

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

  17. Investigation on the effects of gamma irradiation on bitumen

    International Nuclear Information System (INIS)

    Mello, M.S.; Braz, D.; Motta, L.M.G.

    2011-01-01

    Brazil has more than 218,000 km of asphalt-paved highways. Bitumen is a generic term for natural or manufactured black or dark-colored solid, semisolid, or viscous cementitious materials that are composed mainly of high molecular weight hydrocarbons (90-95%). Several papers have shown that the irradiation process has changed the mechanical behavior in some polymers. This work aims to analyze the behavior of Brazilian irradiated Bitumen (CAP 50-70). In order to provide a preliminary evaluation, bitumen samples and cylindrical specimens of asphaltic mixture were tested. The bitumen samples were irradiated 0.1 to 300 kGy, and asphaltic mixture specimen was irradiated 5 to 300 kGy. The cylindrical asphaltic mixture specimen of 10.16 cm diameter used in this study was molded using an asphalt-aggregate mixture. The specimens were irradiated in LIN/UFRJ/Brazil using a Gamma cell Co 60 source of gamma irradiation with an applied dose rate of 29.7 Gy/min. After irradiated, the bitumen samples were subjected to penetration test and the asphaltic mixtures were subjected to indirect tensile strength test (diametral compression) for determination of the resilient modulus, according to ASTM method D 4123. The results of these experiments for each dose were compared with the control (nonirradiated). As expected, the penetration results showed that the ratio (irradiated/non-irradiated) decreases with increasing of irradiation dose for bitumen samples and the resilient modulus results showed that the ratio (irradiated/non-irradiated) increases with increasing of irradiation dose for asphaltic mixture. (author)

  18. The effects of oxide evolution on mechanical properties in proton- and neutron-irradiated Fe-9%Cr ODS steel

    Energy Technology Data Exchange (ETDEWEB)

    Swenson, M.J., E-mail: matthewswenson1@u.boisestate.edu [Boise State University, 1910 University Drive, Boise, ID 83725 (United States); Dolph, C.K. [Boise State University, 1910 University Drive, Boise, ID 83725 (United States); Wharry, J.P. [Boise State University, 1910 University Drive, Boise, ID 83725 (United States); Purdue University, 400 Central Drive, West Lafayette, IN 47907 (United States)

    2016-10-15

    The objective of this study is to evaluate the effect of irradiation on the strengthening mechanisms of a model Fe-9%Cr oxide dispersion strengthened steel. The alloy was irradiated with protons or neutrons to a dose of 3 displacements per atoms at 500 °C. Nanoindentation was used to measure strengthening due to irradiation, with neutron irradiation causing a greater increase in yield strength than proton irradiation. The irradiated microstructures were characterized using transmission electron microscopy and atom probe tomography (APT). Cluster analysis reveals solute migration from the Y-Ti-O-rich nanoclusters to the surrounding matrix after both irradiations, though the effect is more pronounced in the neutron-irradiated specimen. Because the dissolved oxygen atoms occupy interstitial sites in the iron matrix, they contribute significantly to solid solution strengthening. The dispersed barrier hardening model relates microstructure evolution to the change in yield strength, but is only accurate if solid solution contributions to strengthening are considered simultaneously.

  19. Apparatus for filling a container with radioactive solid wastes

    International Nuclear Information System (INIS)

    Adachi, T.; Hiratake, S.

    1984-01-01

    In apparatus for filling a container suitable for storage with radioactive solid wastes arising from atomic power plants or the like, a plasma arc is irradiated toward a portion of the wastes to melt the portion of the wastes; portions of the wastes are successively moved so as to be subjected to irradiation of the plasma arc to continuously melt the wastes; and the melts obtained by melting the wastes are permitted to flow down toward the bottom of the container

  20. Solid targetry at the TESLA Accelerator Installation

    CERN Document Server

    Comor, J J; Rajcevic, M; Kosutic, D; Spasic, M; Vidovic, A; Duricic, J; Nedeljkovic, N

    2002-01-01

    According to the concept of the TESLA Accelerator Installation, the channel for production of radioisotopes has to routinely produce sup 2 sup 0 sup 1 Tl, sup 1 sup 1 sup 1 In, sup 6 sup 7 Ga, sup 1 sup 2 sup 3 I and sup 1 sup 8 F, and a number of other radionuclides for experimental purposes. The production of sup 1 sup 2 sup 3 I and sup 1 sup 8 F will be performed in dedicated, commercial target stations, while a versatile solid target irradiation system is designed for the routine and experimental production of all other radioisotopes. The solid target station is designed to accept targets for both the 7 deg. and 90 deg. irradiation geometry. The targets used for the routine production will be prepared by electroplating on a silver substrate. They can be irradiated with a 1.5 kW beam using the 7 deg. geometry. The cooling of these targets is enhanced by fins on the back of the silver substrate designed so that the highest temperature on the surface of the target does not exceed 110 deg. C. The irradiation ...

  1. Reduction of irradiated tumor cells viability under effect of hyperglycemia

    International Nuclear Information System (INIS)

    Meshcherikova, V.V.; Voloshina, E.A.

    1983-01-01

    On Ehrlich carcinoma cells adapted to growth in vivo and in vitro, cellular mechanisms of short-term hyperglycemia effect have been studied. It has been found that SH by itself leads to the loss of viability of a part of cells of ELD solid tumors manifesting during the first 24 hours upon irradiation according to the interphase death type. Tumor cell radiation injuries arising under the effect of irradiation, usually non realized up to the first division, under SH conditions potentiate its injury effect. The phenomena observed explain partially selective injury of tumoral cells in the course of irradiation under SH conditions which testifies to the prospects of its use in clinics

  2. Solid lubricants and surfaces

    CERN Document Server

    Braithwaite, E R

    1964-01-01

    Solid Lubricants and Surfaces deals with the theory and use of solid lubricants, particularly in colloidal form. Portions of this book are devoted to graphite and molybdenum disulfides, which are widely used solid lubricants in colloidal form. An extensive literature on the laboratory examination of hundreds of solids as potential lubricants is also provided in this text. Other topics discussed include the metals and solid lubricants; techniques for examining surfaces; other solid lubricants; metal shaping; and industrial uses of solid-lubricant dispersions. This publication is beneficial to e

  3. Application bar-code system for solid radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. H.; Kim, T. K.; Kang, I. S.; Cho, H. S.; Son, J. S. [KAERI, Taejon (Korea, Republic of)

    2004-07-01

    Solid radioactive wastes are generated from the post-irradiated fuel examination facility, the irradiated material examination facility, the research reactor, and the laboratories at KAERI. A bar-code system for a solid radioactive waste management of a research organization became necessary while developing the RAWMIS(Radioactive Waste Management Integration System) which it can generate personal history management for efficient management of a waste, documents, all kinds of statistics. This paper introduces an input and output application program design to do to database with data in the results and a stream process of a treatment that analyzed the waste occurrence present situation and data by bar-code system.

  4. Physical-chemical analyses of irradiated papayas ( Carica papaya L.)

    Science.gov (United States)

    Camargo, R. J.; Tadini, C. C.; Sabato, S. F.

    2007-11-01

    Papaya is cultivated in Espírito Santo State/Brazil and as it stands up to irradiation, it is important to validate this technology, since it is already being applied in some countries. Penetration energy, ratio (relation between soluble solids and titrable acidity) and skin color were evaluated to verify the influence of four different doses of irradiation (0.0, 0.5, 0.75 and 1.00 kGy) on papayas, during 21 days. As a result for the skin color and the penetration energy, it was found that in the first days after irradiation, these variables increased with increase in radiation dose; however, after a time lapse, the tendency inverted and the irradiated fruits had a slower ripening process. For the ratio, a very important variable that it is responsible for the fruit taste, no difference was found between irradiated and the control fruit. Color and texture measurements are dependent on the storage temperature.

  5. Physical-chemical analyses of irradiated papayas (Carica papaya L.)

    International Nuclear Information System (INIS)

    Camargo, R.J.; Tadini, C.C.; Sabato, S.F.

    2007-01-01

    Papaya is cultivated in Espirito Santo State/Brazil and as it stands up to irradiation, it is important to validate this technology, since it is already being applied in some countries. Penetration energy, ratio (relation between soluble solids and titrable acidity) and skin color were evaluated to verify the influence of four different doses of irradiation (0.0, 0.5, 0.75 and 1.00 kGy) on papayas, during 21 days. As a result for the skin color and the penetration energy, it was found that in the first days after irradiation, these variables increased with increase in radiation dose; however, after a time lapse, the tendency inverted and the irradiated fruits had a slower ripening process. For the ratio, a very important variable that it is responsible for the fruit taste, no difference was found between irradiated and the control fruit. Color and texture measurements are dependent on the storage temperature

  6. Positron annihilation studies on reactor irradiated and thermal annealed ferrocene

    International Nuclear Information System (INIS)

    Marques Netto, A.; Carvalho, R.S.; Magalhaes, W.F.; Sinisterra, R.D.

    1996-01-01

    Retention and thermal annealing following (n, γ) reaction in solid ferrocene, Fe(C 5 H 5 ) 2 , were studied by positron annihilation lifetime spectroscopy (PAL). Positronium (Ps) formation was observed in the non-irradiated compound with a probability or intensity (I 3 ) of 30%. Upon irradiation of the compound with thermal neutrons in a nuclear reactor, I 3 decreases with increasing irradiation time. Thermal treatment again increases I 3 values from 16% to 25%, revealing an important proportion of molecular reformation without variation of the ortho-positronium lifetime (τ 3 ). These results point out the major influence of the electronic structure as determining the Ps yields in the pure complex. In the irradiated and non irradiated complexes the results are satisfactorily explained on the basis of the spur model. (orig.)

  7. Producing ashless coal extracts by microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ozgur Sonmez; Elife Sultan Giray [Mersin University, Mersin (Turkey). Department of Chemistry

    2011-06-15

    To produce ashless coal extracts, three Turkish coals were extracted with N-methyl-2-pyrrolidinone (NMP), NMP/ethylenediamine (EDA) (17/1, vol/vol) mixture and NMP/tetralin (9/1, vol/vol) mixture through thermal extraction and microwave extraction. Solvent extraction by microwave irradiation (MI) was found to be more effective than that by thermal extraction. Extraction yield of coals in NMP enhanced by addition of a little EDA, but tetralin addition showed variances according to extraction method used. While tetralin addition caused a decrease in the thermal extraction yield, it increased the yield of the extraction by MI. Following the extraction, the solid extracts were produced with ash content ranging from 0.11% to 1.1%. Ash content of solid extract obtained from microwave extraction are less than ash contents of solid extracts obtained from thermal extraction. 34 refs., 7 figs., 5 tabs.

  8. Physicochemical studies for detection of irradiated dry date fruits

    International Nuclear Information System (INIS)

    Farag, S.E.A.; El-Salhy, F.T.; Nassef, A.E.; El-beltagy, A.E.; Moharram, H.A.

    2005-01-01

    The kinetic of the water absorption properties of a selected varieties from the Egyptian dry date fruits were carried out. Sakoti, shamia bida, sokaria, candela and malkabee varieties were used to get an idea about their water absorption properties. Malkabee variety was selected for irradiation at different doses of 0.5, 1, 2, 3, 4 and 5 KGy. In order to obtain a fast, reliable and easy techniques for detecting irradiated dates, several physico-chemical and ultrastructural properties were elucidated in this investigation. Regarding to water absorption, the statistical analysis of the water absorption data revealed that, the amount of water absorption (g water/g dry solid) was decreased with increasing the irradiation doses. This phenomena was confirmed when SEM technique was applied, since irradiation caused shrinkage and reduction in the inner cells. The colour indices were measured by colour analyzer (hunter colorimeter). An inversely proportional relationship was observed between the hue angle and the progress in the irradiation dose, In contrast, direct proportional relationship is strongly observed when the color combination a/b was measured. From the chemical analysis point of view, it was observed that irradiation lowered the amount of total sugars by enhanced reducing sugars. From elucidating the physico-chemical properties of the irradiation date palm, it is now possible to establish a stainable fast, reliable and cheap detection method that could be used to distinguish between the irradiated and non-irradiated dry date fruits

  9. Solid waste management

    OpenAIRE

    Srebrenkoska, Vineta; Golomeova, Saska; Zhezhova, Silvana

    2013-01-01

    Waste is unwanted or useless materials from households, industry, agriculture, hospitals. Waste materials in solid state are classified as solid waste. Increasing of the amount of solid waste and the pressure what it has on the environment, impose the need to introduce sustainable solid waste management. Advanced sustainable solid waste management involves several activities at a higher level of final disposal of the waste management hierarchy. Minimal use of material and energy resources ...

  10. Sensory properties of irradiated foods

    International Nuclear Information System (INIS)

    Plestenjak, A.

    1997-01-01

    Food irradiation is a simple and effective preservation technique. The changes caused by irradiation depend on composition of food, on the absorbed dose, the water content and temperature during and after irradiation. In this paper the changes of food components caused by irradiation, doses for various food irradiation treatments, foods and countries where the irradiation is allowed, and sensory properties of irradiated food are reviewed

  11. Irradiation and storage effects on sensorial and physical characteristics of Keitt mangoes (Mangifera indica L.), quality of irradiated mangoes

    International Nuclear Information System (INIS)

    Lacroix, M.; Jobin, M.; Gagnon, M.

    1992-01-01

    Mango rot caused by fungi is a major problem during storage and marketing. Gamma irradiation was used to determine its effect on the quality of U.S. mangoes irradiated in Canada with 60Co at a minimum dose of 0.60 and a maximum of 0.90 kGy. The sensory evaluation, the texture, the colour and total soluble solids content were assessed during 15 days storage period. Initially, the appearance of irradiated whole mangoes was preferred, but at the end of the storage period the reverse was observed. Although, the irradiation did not extend the shelf-life of mangoes, the pulp of irradiated mangoes was perferred for its colour, odour, taste and texture until day 9. The panelists preferred darker orange colour, fragrant, sweeter and soften mangoes

  12. Bone marrow transplantation in aplastic anemia, acute leukemia and solid tumors

    International Nuclear Information System (INIS)

    Champlin, R.; Feig, S.; Gale, R.P.

    1980-01-01

    Results of bone marrow transplantation for the treatment of aplastic anemia, acute leukemia and solid tumors in the first 141 patients treated between September 1973 and January 1980 are reviewed. Preparation for transplantation with total body irradiation is described. (Auth.)

  13. Provision of radiation safety at the designing of the industrial complex of solid radwaste management (ICSRM)

    International Nuclear Information System (INIS)

    Lobach, S.Yu.; Sevastyuk, O.V.

    2003-01-01

    The article presents the basic principles and criteria of the radiation safety provision, organization of the radiation control system, and dose calculation for the staff irradiation at the construction and operation of the Industrial complex of solid radwaste management (ICSRM)

  14. Irradiation - who needs it?

    International Nuclear Information System (INIS)

    Scoular, C.

    1994-01-01

    In this paper the public's attitudes to the irradiation of food to ensure it is bacteria free and to prolong shelf-life are considered. The need to label irradiated food and to educate the public about its implications are emphasised. The opinions of the large food retailers who maintain that high standards in food processing, hygiene and refrigeration eliminate the need for food irradiation are discussed. (UK)

  15. Identification of irradiated chicken

    International Nuclear Information System (INIS)

    Spiegelberg, A.; Heide, L.; Boegl, K.W.

    1990-01-01

    Frozen chicken and chicken parts were irradiated at a dose of 5 kGy with Co-60. The irradiated chicken and chicken parts were identified by determination of three radiation-induced hydrocarbons from the lipid fraction. Isolation was carried out by high-vacuum distillation with a cold-finger apparatus. The detection of the hydrocarbons was possible in all irradiated samples by gaschromatography/mass spectrometry. (orig.) [de

  16. Food irradiation - now

    International Nuclear Information System (INIS)

    Basson, R.A.

    1989-01-01

    Food irradiation technology in South Africa is about to take its rightful place next to existing food preservation methods in protecting food supplies. This is as a result of several factors, the most important of which is the decision by the Department of Health and Population Development to introduce compulsory labelling of food irradiation. The factors influencing food irradiation technology in South Africa are discussed

  17. Development of blood irradiators

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    This project is designed to improve the techniques of blood irradiation through the development of improved and portable blood irradiators. A portable blood irradiator, consisting of a vitreous carbon body and thulium-170 radiation source, was attached to dogs via a carotid-jugular shunt, and its effects on the immune system measured. The device has demonstrated both significant suppression of circulating lymphocytes and prolonged retention of skin allografts

  18. Irradiation of food

    International Nuclear Information System (INIS)

    Lindell, B.; Danielsson-Tham, M.L.; Hoel, C.

    1983-01-01

    A committee has on instructions from the swedish government made an inquiry into the possible effects on health and working environment from irradition of food. In this report, a review is presented on the known positiv and negative effects of food irradiation Costs, availabilty, shelf life and quality of irradiated food are also discussed. According to the report, the production of radiolysis products during irradiation is not easily evaluated. The health risks from irradiation of spices are estimated to be lower than the risks associated with the ethenoxid treatment presently used. (L.E.)

  19. Gamma irradiation devices

    International Nuclear Information System (INIS)

    Foeldiak, Gabor; Stenger, Vilmos.

    1983-01-01

    The main parameters and the preparation procedures of the gamma radiation sources frequently applied for irradiation purposes are discussed. In addition to 60 Co and 137 Cs sources also the nuclear power plants offer further opportunities: spent fuel elements and products of certain (n,γ) reactions can serve as irradiation sources. Laboratory scale equipments, pilot plant facilities for batch or continuous operation, continuous industrial irradiators and special multipurpose, mobile and panorama type facilities are reviewed including those in Canada, USA, India, the Soviet Union, Hungary, UK, Japan and Australia. For irradiator design the source geometry dependence of the spatial distribution of dose rates can be calculated. (V.N.)

  20. Immunocytoadherence and sublethal irradiation

    International Nuclear Information System (INIS)

    Beaumariage, M.L.; Hiesche, K.; Revesz, L.; Haot, J.

    1975-01-01

    In sublethally irradiated CBA mice, the relative and absolute numbers of spontaneous rosette forming cells against sheep erythrocytes are markedly decreased in bone marrow. The decrease of the absolute number of spontaneous RFC is also important in the spleen in spite of an increase of the RFC relative number above the normal values between the 8th and 12th day after irradiation. The graft of normal bone marrow cells immediately after irradiation or the shielding of a medullary area during irradiation promotes the recovery of the immunocytoadherence capacity of the bone marrow cells but not of the spleen cells [fr

  1. Fluorescence of irradiated hydrocarbons

    International Nuclear Information System (INIS)

    Gulis, I.G.; Evdokimenko, V.M.; Lapkovskij, M.P.; Petrov, P.T.; Gulis, I.M.; Markevich, S.V.

    1977-01-01

    A visible fluorescence has been found out in γ-irradiated aqueous of carbohydrates. Two bands have been distinguished in fluorescence spectra of the irradiated solution of dextran: a short-wave band lambdasub(max)=140 nm (where lambda is a wave length) at lambdasub(β)=380 nm and a long-wave band with lambdasub(max)=540 nm at lambdasub(β)=430 nm. A similar form of the spectrum has been obtained for irradiated solutions of starch, amylopectin, lowmolecular glucose. It has been concluded that a macromolecule of polysaccharides includes fluorescent centres. A relation between fluorescence and α-oxiketon groups formed under irradiation has been pointed out

  2. Planning of irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Caha, A; Krystof, V [Vyzkumny Ustav Klinicke a Experimentalni Onkologie, Brno (Czechoslovakia)

    1979-07-01

    The principles are discussed of the planning of irradiation, ie., the use of the various methods of location of a pathological focus and the possibility of semiautomatic transmission of the obtained data on a two-dimensional or spatial model. An efficient equipment is proposed for large irradiation centres which should cooperate with smaller irradiation departments for which also a range of apparatus is proposed. Irradiation planning currently applied at the Research Institute of Clinical and Experimental Oncology in Brno is described. In conclusion, some of the construction principles of semi-automatic operation of radiotherapy departments are discussed.

  3. Solid-State Spectroscopy An Introduction

    CERN Document Server

    Kuzmany, Hans

    2009-01-01

    Spectroscopic methods have opened up a new horizon in our knowledge of solid-state materials. Numerous techniques using electromagnetic radiation or charged and neutral particles have been invented and worked out to a high level in order to provide more detailed information on the solids. The text presented here is an updated description of such methods as they were originally presented in the first edition. It covers linear response of solids to electromagnetic radiation in a frequency range extending from megahertz or gigahertz as used in spin resonance spectroscopy, to infrared spectroscopy and various forms of spectroscopy in the visible and near visible spectral range. It extends to spectroscopy in the UV and x-ray spectral range and eventually several spectroscopic methods are addressed in the frequency range of g radiation. Likewise linear response to irradiation with particles such as electrons, positrons, muons, neutrons, and atoms is discussed. Instrumental and technical background is provided as we...

  4. High power diode pumped solid state lasers

    International Nuclear Information System (INIS)

    Solarz, R.; Albrecht, G.; Beach, R.; Comaskey, B.

    1992-01-01

    Although operational for over twenty years, diode pumped solid state lasers have, for most of their existence, been limited to individual diodes pumping a tiny volume of active medium in an end pumped configuration. More recent years have witnessed the appearance of diode bars, packing around 100 diodes in a 1 cm bar which have enabled end and side pumped small solid state lasers at the few Watt level of output. This paper describes the subsequent development of how proper cooling and stacking of bars enables the fabrication of multi kill average power diode pump arrays with irradiances of 1 kw/cm peak and 250 W/cm 2 average pump power. Since typical conversion efficiencies from the diode light to the pumped laser output light are of order 30% or more, kW average power diode pumped solid state lasers now are possible

  5. Food irradiation: fiction and reality

    International Nuclear Information System (INIS)

    1991-01-01

    The International Consultative Group on Food Irradiation (IGCFI), sponsored by World Health Organization (WHO), Food and Agriculture Organization (FAO) and the International Atomic Energy Agency (IAEA), with the intention to provide to governments, especially those of developing countries, scientifically correct information about food irradiation, decided to organize a file and questions of general public interest. The document is composed by descriptive files related with the actual situation and future prospective, technical and scientific terms, food irradiation and the radioactivity, chemical transformations in irradiated food, genetic studies, microbiological safety of irradiated food, irradiation and harmlessness, irradiation and additives, packing, irradiation facilities control, process control, irradiation costs and benefits as well as consumers reaction

  6. Detection of food irradiation with luminescence methods

    International Nuclear Information System (INIS)

    Anderle, H.

    1997-06-01

    Food irradiation is applied as method for the preservation of foods, the prevention of food spoilage and the inhibition of food-borne pathogens. Doses exceeding 10 kGy (10 kJ/kg) are not recommended by the WHO. The different legislation requires methods for the detection and the closimetry of irradiated foods. Among the physical methods based on the radiation-induced changes in inorganic, nonhygroscopic crystalline solids are thermoluminescence (TL), photostimulated luminescence (PSL) and lyoluminescence (LL) measurement. The luminescence methods were tested on natural minerals. Pure quartz, feldspars, calcite, aragonite and dolomite of known origin were irradiated, read out and analyzed to determine the influence of luminescence-activators and deactivators. Carbonate minerals show an orange-red TL easily detectable by blue-sensitive photomultiplier tubes. TIL-inactive carbonate samples may be identified by a lyoluminescence method using the reaction of trapped irradiation-generated charge carriers with the solvent during crystal-lattice breakup. The fine-ground mineral is dissolved in an alkaline complexing agent/chemiluminescence sensitizer/chemiluminescence catalyst (EDTA/luminol/hemin) reagent mixture. The TL and PSL of quartz is too weak to contribute a significant part for the corresponding signals in polymineral dust. Alkali and soda feldspar show intense TL and PSL. The temperature maxima in the TL glow curves allow a clear distinction. PSL does not give this additional information, it suffers from bleaching by ambient light and requires light-protection. Grain disinfestated with low irradiation doses (500 Gy) may not identified by both TL and PSL measurement. The natural TL of feldspar particles may be overlap with the irradiation-induced TL of other minerals. As a routine method, irradiated spices are identified with TL measurement. The dust particles have to be enriched by heavy-liquid flotation and centrifugation. The PSL method allows a clear

  7. Opto-chemical response of Makrofol-KG to swift heavy ion irradiation

    Indian Academy of Sciences (India)

    In the present study, the effects of swift heavy ion beam irradiation on the structural, chemical and optical properties of Makrofol solid-state nuclear track detector (SSNTD) were investigated. Makrofol-KG films of 40 m thickness were irradiated with oxygen beam (8+) with fluences ranging between 1010 ion/cm2 and 1012 ...

  8. Effect of neutron irradiation on the cellular stage of Ni-Be alloy decomposition

    International Nuclear Information System (INIS)

    Larikov, L.N.; Borimskaya, S.T.

    1981-01-01

    Effects of neutron irradiation on the cellular stage of decomposition are investigated in deformed supersaturated solid solution Ni-1.92%Be by the X-ray structural and metallographic analyses. Radiation-initiated stimulation of the recovery properties in the deformed alloy and a lower rate of the cellular decomposition in irradiated samples are discovered [ru

  9. Facts about food irradiation: Chemical changes in irradiated foods

    International Nuclear Information System (INIS)

    1991-01-01

    This fact sheet addresses the safety of irradiated food. The irradiation process produces very little chemical change in food, and laboratory experiments have shown no harmful effects in animals fed with irradiated milk powder. 3 refs

  10. Modelling property changes in graphite irradiated at changing irradiation temperature

    CSIR Research Space (South Africa)

    Kok, S

    2011-01-01

    Full Text Available A new method is proposed to predict the irradiation induced property changes in nuclear; graphite, including the effect of a change in irradiation temperature. The currently used method; to account for changes in irradiation temperature, the scaled...

  11. Solid state physics

    CERN Document Server

    Burns, Gerald

    2013-01-01

    Solid State Physics, International Edition covers the fundamentals and the advanced concepts of solid state physics. The book is comprised of 18 chapters that tackle a specific aspect of solid state physics. Chapters 1 to 3 discuss the symmetry aspects of crystalline solids, while Chapter 4 covers the application of X-rays in solid state science. Chapter 5 deals with the anisotropic character of crystals. Chapters 6 to 8 talk about the five common types of bonding in solids, while Chapters 9 and 10 cover the free electron theory and band theory. Chapters 11 and 12 discuss the effects of moveme

  12. Theoretical solid state physics

    CERN Document Server

    Haug, Albert

    2013-01-01

    Theoretical Solid State Physics, Volume 1 focuses on the study of solid state physics. The volume first takes a look at the basic concepts and structures of solid state physics, including potential energies of solids, concept and classification of solids, and crystal structure. The book then explains single-electron approximation wherein the methods for calculating energy bands; electron in the field of crystal atoms; laws of motion of the electrons in solids; and electron statistics are discussed. The text describes general forms of solutions and relationships, including collective electron i

  13. Trialed production of low protein irradiated natural rubber latex in factory scale by gamma irradiation technique

    International Nuclear Information System (INIS)

    Utama, Marga; Herwinarni, S.; Halik, H.M.; Siswanto; Suharyanto; Syamsu, Y.; Handoko, B.

    2006-01-01

    Four tons fresh field natural rubber latex (FNRL) with total solid content 30% were added with 2 phr (part hundred ratio of rubber) normal butyl acrylate (nBA) then irradiated by gamma rays at 25 kGy. The irradiated FNRL was centrifuged, then the properties of irradiated centrifuged natural rubber latex (INRL) and its film were measured before and after storage for 5 months. It is found that the INRL is stable latex during storage in 5 months, with lowest protein, and free nitrosamine content. The tensile strength of INRL film was 24-27 MPa, and modulus 600% was 1,5-2,0 MPa, elongation at break was 900%, and hardness was 27-29 Shore A, while the extractable protein content less than 100 μg/g. (author)

  14. Solid State Studies Section

    Energy Technology Data Exchange (ETDEWEB)

    None

    1974-12-31

    Research is summarized on fuel, fertile, and cladding materials. Results of studies in the field of solid state sciences are also reported. It was found during the studies on the thermal diffusion release of /sup 133/Xe from irradiated thoria--urania powders that during prolonged annealing at high temperatures, there were several sudden burst releases of /sup 133/Xe as a function of time. These sudden bursts appear to be related to the particle size of the powders. Studies on the phase composition of U/sub 3/O/sub 8//su established that the phase obtained at room temperature after heating at 850 deg K is always oxygen deficient. Results of studies on the different modifications of U/sub 3/O/sub 8/ indicated that the so-called delta-phase has a crystal structure almost identical with the beta-phase, yet there were differences in the heats of transition of each of these phases to the alpha-U/sub 3/O/sub 8/ phase at 130 deg C. Studies on fast neutron damage in stainless steel were initiated and results related to damage by void formation were obtained even when the fluencies were only moderately high. Studies on the phase transformations in solids brought out the unusual phase transition behavior of KNO/sub 3/. It was established that the phase transformation attributed to the orthorhombic (II) to the trigonal (I) transition at 129 deg C is essentially a 2-step transition. Results of differential scanning colorimeter (DSC) studies also revealed a peculiar feature which is as yet not understood, namely that on cooling, differential thermal analysis (DTA) showed a III to II phase transition; this is not seen in the DSC. The capabilities of the DSC technique to delineate temperatures of magnetic transitions were demonstrated by studying the transitions in a number of standard substances (metals, alloys, and compounds). In studies on KMnF/sub 3/, it was further demonstrated that the DSC technique is superior in measuring and detecting the heats of crystallographic and

  15. Irradiation-induced amorphization in split-dislocation cores

    International Nuclear Information System (INIS)

    Ovid'ko, I.A.; Rejzis, A.B.

    1999-01-01

    The model describing special splitting of lattice and grain-boundary dislocations as one of the micromechanisms of solid-phase amorphization in irradiated crystals is proposed. Calculation of energy characteristics of the process of dislocations special splitting is carried out [ru

  16. Irradiation of foodstuffs

    International Nuclear Information System (INIS)

    Bugyaki, L.

    1977-01-01

    The author studies the criteria for the harmlessness of irradiation as a food-preservation process. The glucose and proteins of bacto-tryptone, irradiated at 5 Mrads, do not increase the Escherichia Coli C 600 lysogenous bacteriophages, compared to the induction produced by direct irradiation of the strain or to the exposition to nitrogenous yperite. The possible mutagenic effect is therefore different. Wheat flour freshly irradiated at 5 Mrads shows physico-chemical changes. When given to mice as 50% of their ration, it leads to a higher incidence of tumours and a greater number of meiotic chromosome alteration (besides some discreet physio-pathological changes in fertility and longevity). Immunoelectrophoresis in agar or agarose gel does not allow any detection of irradiation of meat, fish or eggs. A vertical electrophoresis in starch gel can lead to a differentiation between frozen or chilled meat and the one that is irradiated at 0.5 or 5 Mrads, but the same thing can't be said for fish or eggs. Lastly an irradiated mushroom shows every sign of freshness but, when planted in a suitable medium, its cuttings do not present any cell proliferation which could give a rapid and simple method of detecting the irradiation. (G.C.)

  17. Materials modified by irradiation

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2007-01-01

    Application of radiation in pharmaceutical sciences and cosmetology, polymer materials, food industry, environment, health camre products and packing production is described. Nano-technology is described more detailed, because it is less known as irradiation using technology. Economic influence of the irradiation on the materials value addition is shown

  18. Special irradiation techniques

    International Nuclear Information System (INIS)

    Colomez, Gerard; Veyrat, J.F.

    1981-01-01

    Irradiation trials conducted on materials-testing reactors should provide a better understanding of the phenomena which characterize the working and evolution in time of electricity-generating nuclear reactors. The authors begin by outlining the objectives behind experimental irradiation (applied to the various nuclear chains) and then describe the special techniques deployed to achieve these objectives [fr

  19. Food irradiation: the facts

    International Nuclear Information System (INIS)

    Webb, Tony; Lang, Tim

    1987-01-01

    The London Food Commission summarizes its concerns about the use of food irradiation in the U.K. resulting from its working group surveys of general public opinion, trading standard officers and the food industry in the U.K., and from experience in countries already permitting irradiation to a variety of foods. (U.K.)

  20. Progress in food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    The volume contains reports from 19 countries on the state of the project in the field of food irradiation (fruit, vegetables, meat, spices) by means of gamma rays. The tests ran up to 1982. Microbiological radiosensitivity and mutagenicity tests provide a yard stick for irradiation efficiency.

  1. Food irradiation: the facts

    International Nuclear Information System (INIS)

    Hamilton, M.

    1990-01-01

    The author explains in simple question and answer form what is entailed in the irradiation of food and attempts to dispel some of the anxieties surrounding the process. Benefits and limitations, controls, labelling safety, and tests for the detection of the use irradiation in food preparation are some of the topics dealt with in outline. (author)

  2. Perspective on food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Recent US Food and Drug Administration approval of irradiation treatment for fruit, vegetables and pork has stimulated considerable discussion in the popular press on the safety and efficacy of irradiation processing of food. This perspective is designed to summarize the current scientific information available on this issue

  3. Food Irradiation in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Kawabata, T.

    1981-09-15

    Since 1967 research activities on food irradiation in Japan have been carried out under the National Food Irradiation Programme by the Japanese Atomic Energy Commission. The programme has been concentrated on the technological and economical feasibility and wholesomeness testings of seven irradiated food items of economic importance to the country, i.e. potatoes, onions, wheat, rice, 'kamaboko' (fish-paste products), 'Vienna' sausages and mandarin oranges. By now most studies, including wholesomeness testings of these irradiated food items, have been completed. In Japan, all foods or food additives for sale are regulated by the Food Sanitation Law enforced in 1947. Based on studies made by the national programme, irradiated potatoes were given 'unconditional acceptance' for human consumption in 1972. At present, irradiated potatoes are the only food item which has so far been approved by the Minister of Health and Welfare. Unless the Minister of Health and Welfare has declared that items are not harmful to human health on obtaining comments from the Food Sanitation Investigation Council, no irradiated food can be processed or sold. In addition, the import of irradiated foodstuffs other than potatoes from foreign countries is prohibited by law.

  4. Post irradiation conical keratosis

    International Nuclear Information System (INIS)

    Vestey, J.P.; Hunter, J.A.A.; Mallet, R.B.; Rodger, A.

    1989-01-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author)

  5. Post irradiation conical keratosis

    Energy Technology Data Exchange (ETDEWEB)

    Vestey, J.P.; Hunter, J.A.A. (Royal Infirmary, Edinburgh (UK)); Mallet, R.B. (Westminster Hospital, London (UK)); Rodger, A. (Western General Hospital, Edinburgh (UK))

    1989-03-01

    The authors have recently seen 3 patients affected by a widespread eruption of minute keratoses confined to areas of irradiated skin with clinical and histologial features of which they have been unable to find previous literary descriptions. A fourth patient with similar clinical and histopathological features occurring after exposure only to actinic irradiation is described. (author).

  6. Irradiation damage in superconductors

    International Nuclear Information System (INIS)

    Quere, Y.

    1989-01-01

    Most superconductors are quite sensitive to irradiation defects. Critical temperatures may be depressed, critical currents may be increased, by irradiation, but other behaviours may be encountered. In compounds, the sublattice in which defects are created is of significant importance. 24 refs

  7. Food preservation by irradiation

    International Nuclear Information System (INIS)

    Labots, H.; Huis in 't Veld, G.J.P.; Verrips, C.T.

    1985-01-01

    After a review of several methods for the preservation of food and the routes of food infections, the following chapters are devoted to the preservation by irradiation. Applications and legal aspects of food irradiation are described. Special reference is made to the international situation. (Auth.)

  8. Food irradiation control

    International Nuclear Information System (INIS)

    Ley, F.J.

    1988-01-01

    A brief review is given of the control and monitoring of food irradiation with particular emphasis on the UK situation. After describing legal aspects, various applications of food irradiation in different countries are listed. Other topics discussed include code of practice for general control for both gamma radiation and electron beam facilities, dose specification, depth dose distribution and dosimetry. (U.K.)

  9. Uniformly irradiated polymer film

    International Nuclear Information System (INIS)

    Fowler, S.L.

    1979-01-01

    Irradiated film having substantial uniformity in the radiation dosage profile is produced by irradiating the film within a trough having lateral deflection blocks disposed adjacent the film edges for deflecting electrons toward the surface of the trough bottom for further deflecting the electrons toward the film edge

  10. Solid phase radioimmunoassays

    International Nuclear Information System (INIS)

    Wide, L.

    1977-01-01

    Solid phase coupled antibodies were introduced to facilitate the separation of bound and free labelled ligand in the competitive inhibition radioimmunoassay. Originally, the solid matrix used was in the form of small particles and since then a number of different matrices have been used such as very fine powder particles, gels, paper and plastic discs, magnetic particles and the inside surface of plastic tubes. The coupling of antibodies may be that of a covalent chemical binding, a strong physical adsorbtion, or an immunological binding to a solid phase coupled antigen. New principles of radioimmunoassay such as the solid phase sandwich techniques and the immunoradiometric assay were developped from the use of solid phase coupled antigens and antibodies. The solid phase sandwich techniques are reagent excess methods with a very wide applicability. Several of the different variants of solid phase techniques are suitable for automation. Advantages and disadvantages of solid phase radioimmunoassays when compared with those using soluble reagents are discussed. (orig.) [de

  11. Dose verification by OSLDs in the irradiation of cell cultures

    International Nuclear Information System (INIS)

    Meca C, E. A.; Bourel, V.; Notcovich, C.; Duran, H.

    2015-10-01

    The determination of value of irradiation dose presents difficulties when targets are irradiated located in regions where electronic equilibrium of charged particle is not reached, as in the case of irradiation -in vitro- of cell lines monolayer-cultured, in culture dishes or flasks covered with culture medium. The present study aimed to implement a methodology for dose verification in irradiation of cells in culture media by optically stimulated luminescence dosimetry (OSLD). For the determination of the absorbed dose in terms of cell proliferation OSL dosimeters of aluminum oxide doped with carbon (Al 2 O 3 :C) were used, which were calibrated to the irradiation conditions of culture medium and at doses that ranged from 0.1 to 15 Gy obtained with a linear accelerator of 6 MV photons. Intercomparison measurements were performed with an ionization chamber of 6 cm 3 . Different geometries were evaluated by varying the thicknesses of solid water, air and cell culture medium. The results showed deviations below 2.2% when compared with the obtained doses of OSLDs and planning system used. Also deviations were observed below 3.4% by eccentric points of the irradiation plane, finding homogeneous dose distribution. Uncertainty in the readings was less than 2%. The proposed methodology contributes a contribution in the dose verification in this type of irradiations, eliminating from the calculation uncertainties, potential errors in settling irradiation or possible equipment failure with which is radiating. It also provides certainty about the survival curves to be plotted with the experimental data. (Author)

  12. Irradiation Creep in Graphite

    Energy Technology Data Exchange (ETDEWEB)

    Ubic, Rick; Butt, Darryl; Windes, William

    2014-03-13

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

  13. Irradiation of goods

    International Nuclear Information System (INIS)

    Lunt, R.E.

    1987-01-01

    Mechanical handling apparatus is adapted to handle goods, such as boxed fruit, during a process of irradiation, in palletized form. Palletized goods are loaded onto wheeled vehicles in a loading zone. Four vehicles are wheeled on a track into an irradiation zone via a door in a concrete shield. The vehicles are arranged in orthogonal relationship around a source of square section. Turntables are positioned at corners of the square shaped rail truck around the source selectively to turn the vehicles to align then with track sections. Mechanical manipulating devices are positioned in the track sections opposed to sides of the source. During irradiation, the vehicles and their palletized goods are cylically moved toward the source to offer first sides of the goods for irradiation and are retraced from the source and are pivoted through 90 0 to persent succeeding sides of the goods for irradiation

  14. Irradiation of packaged food

    International Nuclear Information System (INIS)

    Kilcast, D.

    1990-01-01

    Food irradiation is used to improve the safety of food by killing insects and microorganisms, to inhibit sprouting in crops such as onions and potatoes and to control ripening in agricultural produce. In order to prevent re-infestation and re-contamination it is essential that the food is suitably packed. Consequently, the packaging material is irradiated whilst in contact with the food, and it is important that the material is resistant to radiation-induced changes. In this paper the nature of the irradiation process is reviewed briefly, together with the known effects of irradiation on packaging materials and their implications for the effective application of food irradiation. Recent research carried out at the Leatherhead Food RA on the possibility of taint transfer into food is described. (author)

  15. Issues in food irradiation

    International Nuclear Information System (INIS)

    Mills, S.

    1987-04-01

    This discussion paper has two goals: first, to raise public awareness of food irradiation, an emerging technology in which Canada has the potential to build a new industry, mainly oriented to promising overseas markets; and second, to help build consensus among government and private sector decision makers about what has to be done to realize the domestic and export potential. The following pages discuss the potential of food irradiation; indicate how food is irradiated; outline the uses of food irradiation; examine questions of the safety of the equipment and both the safety and nutritional value of irradiated food; look at international commercial developments; assess the current and emerging domestic scene; and finally, draw some conclusions and offer suggestions for action

  16. Extracorporeal irradiation -Physicist perspective

    International Nuclear Information System (INIS)

    Vijayaprabhu, N.; Saravanan, K.S.; Gunaseelan; Vivekanandam, S.; Reddy, K.S.; Parthasarathy; Mourougan, S.; Elangovan, K.

    2008-01-01

    Extracorporeal irradiation (ECI) involves irradiation of body tissues, particularly malignant bones of the extremities, outside the body. This involves en bloc resection of the tumour, extracorporeal irradiation of the bone segment with a single dose of 50 Gy or more, and reimplantation of the irradiated bone with fixation devices. Bone tumours like Ewing's Sarcoma, Chondrosarcoma and Oesteosarcoma; in the involved sites like femur, tibia, humerus, ilium and sacrum can be treated with ECI. The reimplanted bone simply acts as a framework for appositional bone growth from surrounding healthy bones. The conventional indications for postoperative irradiation are still applied. The major advantages of ECI are the precise anatomic fit of the reimplanted bone segment, preservation of joint mobility and its potential in avoiding the growth discrepancy commonly seen in prosthetic replacement. The use of ECI was first described in 1968 and practiced in Australia since 1996. In our center, we have completed six ECIs

  17. The effect of gamma irradiation on the microbial load, mineral concentration and sensory characteristics of licorice (Glycyrrhiza glabra L.)

    International Nuclear Information System (INIS)

    Al-Bachir, M.; Lahham, G.

    2001-10-01

    Ground licorice roots were exposed to 0, 5, 10, 15 and 20 kGy of gamma radiation in a 60 Co source. Irradiated and non-irradiated samples were stored at room temperature. Microbial population, viscosity, concentration of some minerals and sensory properties of the extract were evaluated after 0 and 12 months of storage. The results indicated that, immediately after irradiation, used doses reduced the microbial count and D 10 was at about 2 kGy. No effect was observed in total dissolved solids in the extract of licorice roots. Glycyrrhizinic acid concentration in extract and viscosity of suspension produced from irradiated roots were lower than in non-irradiated ones. Sensory evaluation indicated that no significant differences (P + , Ca ++ and K + ) concentration in extract produced from irradiated roots were lower than in non-irradiated ones, and no significant differences (P< 0.05) were found in viscosity between suspension of irradiated and non-irradiated roots. (author)

  18. Laser cooling of solids

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, Richard I [Los Alamos National Laboratory; Sheik-bahae, Mansoor [UNM

    2008-01-01

    We present an overview of solid-state optical refrigeration also known as laser cooling in solids by fluorescence upconversion. The idea of cooling a solid-state optical material by simply shining a laser beam onto it may sound counter intuitive but is rapidly becoming a promising technology for future cryocooler. We chart the evolution of this science in rare-earth doped solids and semiconductors.

  19. Effect of irradiation on the biochemical and organoleptic changes during the ripening of papaya and mango fruits

    International Nuclear Information System (INIS)

    Lacroix, M.; Bernard, L.; Jobin, M.; Milot, S.; Gagnon, M.

    1990-01-01

    Papaya and mango rot caused by fungi is a major problem during storage and marketing. Gamma irradiation treatment was used to determine its effect on the quality of papayas and mangoes irradiated at 0,5 to 0,95 kGy. The level of respiration, soluble solids, texture, vitamin C and the sensorial evaluation were effectuated. The results indicate that irradiation treatment reduces significantly (p≤0,001) weakens the texture of mangoes. The content of soluble solids and vitamin C are not significantly affected by the irradiation. The sensory evaluation indicates that up to 0,95 kGy the sensorial quality is not changed. (author)

  20. Solid State Division

    International Nuclear Information System (INIS)

    Green, P.H.; Watson, D.M.

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces

  1. Solid State Division

    Energy Technology Data Exchange (ETDEWEB)

    Green, P.H.; Watson, D.M. (eds.)

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces. (LSP)

  2. Solid state radiation dosimetry

    International Nuclear Information System (INIS)

    Moran, P.R.

    1976-01-01

    Important recent developments provide accurate, sensitive, and reliable radiation measurements by using solid state radiation dosimetry methods. A review of the basic phenomena, devices, practical limitations, and categories of solid state methods is presented. The primary focus is upon the general physics underlying radiation measurements with solid state devices

  3. Dedicated Tool for Irradiation and Electrical Measurement of Large Surface Samples on the Beamline of a 2.5 Mev Pelletron Electron Accelerator: Application to Solar Cells

    Directory of Open Access Journals (Sweden)

    Lefèvre Jérémie

    2017-01-01

    After a brief description of the SIRIUS irradiation facility hosted at Laboratoire des Solides Irradiés (LSI, this paper gives detailed information about the Large Surface Irradiated-Cell (LSIC device. Preliminary results obtained during the ongoing qualification phase of the setup are also discussed.

  4. Beneficial Uses Program. Progress report, period ending December 31, 1977. [Irradiated sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    The Beneficial Uses Program is a comprehensive program to develop the necessary technologies for cost-beneficial uses of existing and future surplus radioactive materials. The major portion of the work at Sandia is concentrated in two sub-programs: the Waste Resources Utilization Program and the Separation Technology and Source Development Program. Progress is reported on: (1) the Sandia Irradiator for Dried Sewage Solids; (2) bacteriology; (3) mycology; (4) virology; (5) animal feeds containing irradiated sewage solids; (6) use of irradiated sewage sludge as fertilizer; and (7) development of /sup 90/Sr and /sup 137/Cs radiation sources obtained from radioactive wastes. (TFD)

  5. Beneficial Uses Program. Progress report, period ending March 31, 1979. [Irradiated sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-01

    The Beneficial Uses Program is a comprehensive program to develop the necessary technologies for cost-beneficial uses of existing and future surplus radioactive materials. The major portion of the work at Sandia is concentrated in two sub-programs: the Waste Resources Utilization Program and the Separation Technology and Source Development Program. Progress is reported on: (1) the Sandia Irradiator for Dried Sewage Solids; (2) bacteriology; (3) mycology; (4) virology; (5) animal feeds containing irradiated sewage solids; (6) use of irradiated sewage sludge as fertilizer; and (7) development of /sup 137/Cs radiation sources obtained from radioactive wastes. (TFD)

  6. Beneficial Uses Program. Progress report for period ending June 30, 1978. [Irradiated sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The Beneficial Uses Program is a comprehensive program to develop the necessary technologies for cost-beneficial uses of existing and future surplus radioactive materials. The major portion of the work at Sandia is concentrated in two sub-programs: the Waste Resources Utilization Program and the Separation Technology and Source Development Program. Progress is reported on: (1) the Sandia Irradiator for Dried Sewage Solids; (2) bacteriology; (3) mycology; (4) virology; (5) animal feeds containing irradiated sewage solids; (6) use of irradiated sewage sludge as fertilizer; and (7) development of /sup 137/Cs radiation sources obtained from radioactive wastes. (TFD)

  7. Studies on the supposition of liquid source for irradiation and its dose distribution, (1)

    International Nuclear Information System (INIS)

    Yoshimura, Seiji; Nishida, Tsuneo

    1977-01-01

    Recently radio isotope has been used and applied in the respective spheres. The application of the effects by irradiation will be specially paid attention to in the future. Today the source for irradiation has been considered to be the thing sealed in the solid state into various capsules. So we suppose that we use liquid radio isotope as the source for irradiation. This is because there are some advantages compared with the solid source in its freedom of the shape or additional easiness at attenuation. In these experiments we measured the dose distribution by the columnar liquid source. We expect that these will be put to practical use. (auth.)

  8. Investigation of radiation defects in solids using the EXAFS method

    International Nuclear Information System (INIS)

    Eritsyan, G.N.

    1983-01-01

    The exafs method is proposed as a more informative, universal one to investigate the radiation defects in solids. The successful results as obtained by the author using the synchrotron radiation source are reported for the first time. The measurements were carried out in GaAsP crystals irradiated with 50 MeV electrons

  9. Clarification of dissolved irradiated light-water-reactor fuel

    International Nuclear Information System (INIS)

    Rodrigues, G.C.

    1983-02-01

    Bench-scale studies with actual dissolved irradiated light water reactor (LWR) fuels showed that continuous centrifugation is a practical clarification method for reprocessing. Dissolved irradiated LWR fuel was satisfactorily clarified in a bench-scale, continuous-flow bowl centrifuge. The solids separated were successfully reslurried in water. When the reslurried solids were mixed with clarified centrate, the resulting suspension behaved similar to the original dissolver solution during centrifugation. Settling rates for solids in actual irradiated fuel solutions were measured in a bottle centrifuge. The results indicate that dissolver solutions may be clarified under conditions achievable by available plant-scale centrifuge technology. The effective particle diameter of residual solids was calculated to be 0.064 microns for Oconee-1 fuel and 0.138 microns for Dresden-1 fuel. Filtration was shown unsuitable for clarification of LWR fuel solutions. Conventional filtration with filter aid would unacceptably complicate remote canyon operation and maintenance, might introduce dissolved silica from filter aids, and might irreversibly plug the filter with dissolver solids. Inertial filtration exhibited irreversible pluggage with nonradioactive stand-in suspensions under all conditions tested

  10. Effect of gamma irradiation on the sugar and protein composition of Iraqi dates

    International Nuclear Information System (INIS)

    Auda, H.; Khalaf, Z.; Mirjan, J.

    1978-01-01

    Completely ripened date fruits of several Iraqi varieties were irradiated with 30, 70, 100, 270 and 500krad of gamma irradiation and stored at a temperature of 25-35 0 C in wooden boxes or in plastic bags. At various intervals samples were taken and analysed by paper-chromatography, gas-chromatography and spectrophotometry for quantitative and qualitative changes in carbohydrates. The results showed no effect of gamma irradiation on reducing sugar and major carbohydrate components. The formation of malonaldehyde under gamma irradiation of dates and solid standard sugars was also studied up to 500krad. The results showed no formation of malonaldehyde in irradiated date samples as well as standard sugars. Gamma irradiation showed no effect on the protein content of dates. However, storage showed some reduction in the protein content of both unirradiated and irradiated samples. (author)

  11. Effect of ion beam irradiation of fresh-keeping of strawberry

    International Nuclear Information System (INIS)

    Lei Qing; Huang Min; Wu Ling; Mo Yan; Du Xiaoying; Xie Yan; Wang Yan; Gao Peng; Kang Ju

    2011-01-01

    Effects of ion beam irradiation on strawberry quality were studied, in this study and microbial biomass, decay index, weight loss and biological index were detected. Irradiation dosage were 1.0, 2.0 and 3.0 kGy. The results showed that the irradiation decreased the number of microorganism in the strawberry and delayed the rotten speed. The soluble solide, Vc and total acid content of irradiated strawberry reduced slower than that of control. It indicated that the irradiation dosage did not affect the quality of strawberry in this study . Therefore, 2.0 ∼ 3.0 kGy of ion beam irradiation were an excellent irradiation dosage for strawberry preservation. (authors)

  12. Irradiation-Induced Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-08-09

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

  13. Food irradiation 2009

    International Nuclear Information System (INIS)

    Narvaiz, Patricia

    2009-01-01

    Food irradiation principles; its main applications, advantages and limitations; wholesomeness, present activities at Ezeiza Atomic Centre; research coordinated by the International Atomic Energy Agency; capacity building; and some aspects on national and international regulations, standards and commercialization are briefly described. At present 56 countries authorize the consumption of varied irradiated foods; trade is performed in 32 countries, with about 200 irradiation facilities. Argentina pioneered nuclear energy knowledge and applications in Latin America, food irradiation included. A steady growth of food industrial volumes treated in two gamma facilities can be observed. Food industry and producers show interest towards new facilities construction. However, a 15 years standstill in incorporating new approvals in the Argentine Alimentary Code, in spite of consecutive request performed either by CNEA or some food industries restricts, a wider industrial implementation, which constitute a drawback to future regional commercialization in areas such as MERCOSUR, where Brazil since 2000 freely authorize food irradiation. Besides, important chances in international trade with developed countries will be missed, like the high fresh fruits and vegetables requirements United States has in counter-season, leading to convenient sale prices. The Argentine food irradiation facilities have been designed and built in the country. Argentina produces Cobalt-60. These capacities, unusual in the world and particularly in Latin America, should be protected and enhanced. Being the irradiation facilities scarce and concentrated nearby Buenos Aires city, the possibilities of commercial application and even research and development are strongly limited for most of the country regions. (author) [es

  14. Combustibility of tetraphenylborate solids

    International Nuclear Information System (INIS)

    Walker, D.D.

    1989-01-01

    Liquid slurries expected under normal in-tank processing (ITP) operations are not ignitible because of their high water content. However, deposits of dry solids from the slurries are combustible and produce dense, black smoke when burned. The dry solids burn similarly to Styrofoam and more easily than sawdust. It is the opinion of fire hazard experts that a benzene vapor deflagration could ignite the dry solids. A tetraphenylborate solids fire will rapidly plug the waste tank HEPA ventilation filters due to the nature of the smoke produced. To prevent ignition and combustion of these solids, the waste tanks have been equipped with a nitrogen inerting system

  15. The biological effectiveness of antiproton irradiation

    DEFF Research Database (Denmark)

    Holzscheiter, Michael H.; Bassler, Niels; Agazaryan, Nzhde

    2006-01-01

    ever measurements of the biological effectiveness of antiprotons. Materials and methods: V79 cells were suspended in a semi-solid matrix and irradiated with 46.7 MeV antiprotons, 48 MeV protons, or 60Co c-rays. Clonogenic survival was determined as a function of depth along the particle beams. Dose...... and particle fluence response relationships were constructed from data in the plateau and Bragg peak regions of the beams and used to assess the biological effectiveness. Results: Due to uncertainties in antiproton dosimetry we defined a new term, called the biologically effective dose ratio (BEDR), which...... has a higher relative biological effectiveness (RBE). Conclusion: We have produced the first measurements of the biological consequences of antiproton irradiation. These data substantiate theoretical predictions of the biological effects of antiproton annihilation within the Bragg peak, and suggest...

  16. Sublethal irradiation promotes invasiveness of neuroblastoma cells

    International Nuclear Information System (INIS)

    Schweigerer, Lothar; Rave-Fraenk, Margret; Schmidberger, Heinz; Hecht, Monica

    2005-01-01

    Neuroblastoma is the most frequent extracranial solid tumour of childhood. Despite multiple clinical efforts, clinical outcome has remained poor. Neuroblastoma is considered to be radiosensitive, but some clinical studies including the German trial NB90 failed to show a clinical benefit of radiation therapy. The mechanisms underlying this apparent discrepancy are still unclear. We have therefore investigated the effects of radiation on neuroblastoma cell behaviour in vitro. We show that sublethal doses of irradiation up-regulated the expression of the hepatocyte growth factor (HGF) and its receptor c-Met in some neuroblastoma cell lines. The increase in HGF/c-Met expression was correlated with enhanced invasiveness and activation of proteases degrading the extracellular matrix. Thus, irradiation at sublethal doses may promote the metastatic dissemination of neuroblastoma cells through activating the HGF/c-Met pathway and triggering matrix degradation

  17. History of Solid Rockets

    Science.gov (United States)

    Green, Rebecca

    2017-01-01

    Solid rockets are of interest to the space program because they are commonly used as boosters that provide the additional thrust needed for the space launch vehicle to escape the gravitational pull of the Earth. Larger, more advanced solid rockets allow for space launch vehicles with larger payload capacities, enabling mankind to reach new depths of space. This presentation will discuss, in detail, the history of solid rockets. The history begins with the invention and origin of the solid rocket, and then goes into the early uses and design of the solid rocket. The evolution of solid rockets is depicted by a description of how solid rockets changed and improved and how they were used throughout the 16th, 17th, 18th, and 19th centuries. Modern uses of the solid rocket include the Solid Rocket Boosters (SRBs) on the Space Shuttle and the solid rockets used on current space launch vehicles. The functions and design of the SRB and the advancements in solid rocket technology since the use of the SRB are discussed as well. Common failure modes and design difficulties are discussed as well.

  18. Solid Base Catalysis

    CERN Document Server

    Ono, Yoshio

    2011-01-01

    The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

  19. Alaskan Commodities Irradiation Project

    International Nuclear Information System (INIS)

    Zarling, J.P.; Swanson, R.B.; Logan, R.R.

    1988-01-01

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

  20. Irradiation of UO2

    International Nuclear Information System (INIS)

    Stevanovic, M.

    1965-10-01

    Based on the review of the available literature concerned with UO 2 irradiation, this paper describes and explains the phenomena initiated by irradiation of the UO 2 fuel in a reactor dependent on the burnup level and temperature. A comprehensive review of UO 2 radiation damage studies is given as a broad research program. This part includes the abilities of our reactor as well as needed elements for such study. The third part includes the definitions of the specific power, burnup level and temperature in the center of the fuel element needed for planning and performing the irradiation. Methods for calculating these parameters are included [sr