WorldWideScience

Sample records for irradiated ruby samples

  1. MacRuby Ruby and Cocoa on OS X

    CERN Document Server

    Aimonetti, Matt

    2011-01-01

    Want to build native Mac OS X applications with a sleek, developer-friendly alternative to Objective-C? MacRuby is an ideal choice. This in-depth guide shows you how Apple's implementation of Ruby gives you access to all the features available to Objective-C programmers. You'll get clear, detailed explanations of MacRuby, including quick programming techniques such as prototyping. Perfect for programmers at any level, this book is packed with code samples and complete project examples. If you use Ruby, you can tap your skills to take advantage of Interface Builder, Cocoa libraries, the Objec

  2. Ruby under a microscope learning Ruby internals through experiment

    CERN Document Server

    Shaughnessy, Pat

    2013-01-01

    How Ruby Works Under the HoodRuby is a powerful programming language with a focus on simplicity, but beneath its elegant syntax it performs countless unseen tasks.Ruby Under a Microscope gives you a hands-on look at Ruby's core, using extensive diagrams and thorough explanations to show you how Ruby is implemented (no C skills required). Author Pat Shaughnessy takes a scientific approach, laying out a series of experiments with Ruby code to take you behind the scenes of how programming languages work. You'll even find information on JRuby and Rubinius (two alternative implementations of Ruby),

  3. BioRuby: bioinformatics software for the Ruby programming language.

    Science.gov (United States)

    Goto, Naohisa; Prins, Pjotr; Nakao, Mitsuteru; Bonnal, Raoul; Aerts, Jan; Katayama, Toshiaki

    2010-10-15

    The BioRuby software toolkit contains a comprehensive set of free development tools and libraries for bioinformatics and molecular biology, written in the Ruby programming language. BioRuby has components for sequence analysis, pathway analysis, protein modelling and phylogenetic analysis; it supports many widely used data formats and provides easy access to databases, external programs and public web services, including BLAST, KEGG, GenBank, MEDLINE and GO. BioRuby comes with a tutorial, documentation and an interactive environment, which can be used in the shell, and in the web browser. BioRuby is free and open source software, made available under the Ruby license. BioRuby runs on all platforms that support Ruby, including Linux, Mac OS X and Windows. And, with JRuby, BioRuby runs on the Java Virtual Machine. The source code is available from http://www.bioruby.org/. katayama@bioruby.org

  4. Formation of highly toxic hydrogen cyanide upon ruby laser irradiation of the tattoo pigment phthalocyanine blue

    Science.gov (United States)

    Schreiver, Ines; Hutzler, Christoph; Laux, Peter; Berlien, Hans-Peter; Luch, Andreas

    2015-08-01

    Since laser treatment of tattoos is the favored method for the removing of no longer wanted permanent skin paintings, analytical, biokinetics and toxicological data on the fragmentation pattern of commonly used pigments are urgently required for health safety reasons. Applying dynamic headspace—gas chromatography with mass spectrometric detection (DHS—GC/MS) and comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GCxGC—ToF-MS), we identified 1,2-benzene dicarbonitrile, benzonitrile, benzene, and the poisonous gas hydrogen cyanide (HCN) as main fragmentation products emerging dose-dependently upon ruby laser irradiation of the popular blue pigment copper phthalocyanine in suspension. Skin cell viability was found to be significantly compromised at cyanide levels of ≥1 mM liberated during ruby laser irradiation of >1.5 mg/ml phthalocyanine blue. Further, for the first time we introduce pyrolysis-GC/MS as method suitable to simulate pigment fragmentation that may occur spontaneously or during laser removal of organic pigments in the living skin of tattooed people. According to the literature such regular tattoos hold up to 9 mg pigment/cm2 skin.

  5. A function-based screen for seeking RubisCO active clones from metagenomes: novel enzymes influencing RubisCO activity.

    Science.gov (United States)

    Böhnke, Stefanie; Perner, Mirjam

    2015-03-01

    Ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) is a key enzyme of the Calvin cycle, which is responsible for most of Earth's primary production. Although research on RubisCO genes and enzymes in plants, cyanobacteria and bacteria has been ongoing for years, still little is understood about its regulation and activation in bacteria. Even more so, hardly any information exists about the function of metagenomic RubisCOs and the role of the enzymes encoded on the flanking DNA owing to the lack of available function-based screens for seeking active RubisCOs from the environment. Here we present the first solely activity-based approach for identifying RubisCO active fosmid clones from a metagenomic library. We constructed a metagenomic library from hydrothermal vent fluids and screened 1056 fosmid clones. Twelve clones exhibited RubisCO activity and the metagenomic fragments resembled genes from Thiomicrospira crunogena. One of these clones was further analyzed. It contained a 35.2 kb metagenomic insert carrying the RubisCO gene cluster and flanking DNA regions. Knockouts of twelve genes and two intergenic regions on this metagenomic fragment demonstrated that the RubisCO activity was significantly impaired and was attributed to deletions in genes encoding putative transcriptional regulators and those believed to be vital for RubisCO activation. Our new technique revealed a novel link between a poorly characterized gene and RubisCO activity. This screen opens the door to directly investigating RubisCO genes and respective enzymes from environmental samples.

  6. Pigmented guinea pig skin irradiated with Q-switched ruby laser pulses. Morphologic and histologic findings

    Energy Technology Data Exchange (ETDEWEB)

    Dover, J.S.; Margolis, R.J.; Polla, L.L.; Watanabe, S.; Hruza, G.J.; Parrish, J.A.; Anderson, R.R.

    1989-01-01

    Q-switched ruby laser pulses cause selective damage to cutaneous pigmented cells. Repair of this selective damage has not been well described. Therefore, using epilated pigmented and albino guinea pig skin, we studied the acute injury and tissue repair caused by 40-ns, Q-switched ruby laser pulses. Gross observation and light and electron microscopy were performed. No specific changes were evident in the albino guinea pigs. In pigmented animals, with radiant exposures of 0.4 J/cm2 or greater, white spots confined to the 2.5-mm exposure sites developed immediately and faded over 20 minutes. Delayed depigmentation occurred at seven to ten days, followed by full repigmentation by four to eight weeks. Regrowing hairs in sites irradiated at and above 0.4 J/cm2 remained white for at least four months. Histologically, vacuolation of pigment-laden cells was seen immediately in the epidermis and the follicular epithelium at exposures of 0.3 J/cm2 and greater. Melanosomal disruption was seen immediately by electron microscopy at and above 0.3 J/cm2. Over the next seven days, epidermal necrosis was followed by regeneration of a depigmented epidermis. By four months, melanosomes and melanin pigmentation had returned; however, hair follicles remained depigmented and devoid of melanocytes. This study demonstrates that selective melanosomal disruption caused by Q-switched ruby laser pulses leads to transient cutaneous depigmentation and persistent follicular depigmentation. Potential exists for selective treatment of pigmented epidermal and dermal lesions with this modality.

  7. Timely Rubies

    DEFF Research Database (Denmark)

    Brichet, Nathalia Sofie

    2018-01-01

    Based on anthropological fieldwork in Greenland, I explore how rubies as a natural resource create and organise forms of temporality in order for the stones to appear as a valuable good. I suggest that a circular argument is at play with regard to the Greenlandic rubies, namely that time creates ...... embedded in and generated through social practices. Accordingly, time in relation to mining does not so much present a philosophical challenge, but is rather just a “thing” that happens to be good to think a Greenlandic resource landscape through – as are rubies.......Based on anthropological fieldwork in Greenland, I explore how rubies as a natural resource create and organise forms of temporality in order for the stones to appear as a valuable good. I suggest that a circular argument is at play with regard to the Greenlandic rubies, namely that time creates...... valuable rubies and rubies create time. I further argue that this interdependence is an important self-fulfilling driver in creating a viable mining industry for gemstones in Greenland. A focus on temporality enables me to engage in this circularity and thereby explore one component in the work of making...

  8. The Ruby programming language

    CERN Document Server

    Flanagan, David

    2008-01-01

    This book begins with a quick-start tutorial to the language, and then explains the language in detail from the bottom up: from lexical and syntactic structure to datatypes to expressions and statements and on through methods, blocks, lambdas, closures, classes and modules. The book also includes a long and thorough introduction to the rich API of the Ruby platform, demonstrating -- with heavily-commented example code -- Ruby's facilities for text processing, numeric manipulation, collections, input/output, networking, and concurrency. An entire chapter is devoted to Ruby's metaprogramming capabilities. The Ruby Programming Language documents the Ruby language definitively but without the formality of a language specification. It is written for experienced programmers who are new to Ruby, and for current Ruby programmers who want to challenge their understanding and increase their mastery of the language.

  9. The Ruby UCSC API: accessing the UCSC genome database using Ruby.

    Science.gov (United States)

    Mishima, Hiroyuki; Aerts, Jan; Katayama, Toshiaki; Bonnal, Raoul J P; Yoshiura, Koh-ichiro

    2012-09-21

    The University of California, Santa Cruz (UCSC) genome database is among the most used sources of genomic annotation in human and other organisms. The database offers an excellent web-based graphical user interface (the UCSC genome browser) and several means for programmatic queries. A simple application programming interface (API) in a scripting language aimed at the biologist was however not yet available. Here, we present the Ruby UCSC API, a library to access the UCSC genome database using Ruby. The API is designed as a BioRuby plug-in and built on the ActiveRecord 3 framework for the object-relational mapping, making writing SQL statements unnecessary. The current version of the API supports databases of all organisms in the UCSC genome database including human, mammals, vertebrates, deuterostomes, insects, nematodes, and yeast.The API uses the bin index-if available-when querying for genomic intervals. The API also supports genomic sequence queries using locally downloaded *.2bit files that are not stored in the official MySQL database. The API is implemented in pure Ruby and is therefore available in different environments and with different Ruby interpreters (including JRuby). Assisted by the straightforward object-oriented design of Ruby and ActiveRecord, the Ruby UCSC API will facilitate biologists to query the UCSC genome database programmatically. The API is available through the RubyGem system. Source code and documentation are available at https://github.com/misshie/bioruby-ucsc-api/ under the Ruby license. Feedback and help is provided via the website at http://rubyucscapi.userecho.com/.

  10. The Ruby UCSC API: accessing the UCSC genome database using Ruby

    Science.gov (United States)

    2012-01-01

    Background The University of California, Santa Cruz (UCSC) genome database is among the most used sources of genomic annotation in human and other organisms. The database offers an excellent web-based graphical user interface (the UCSC genome browser) and several means for programmatic queries. A simple application programming interface (API) in a scripting language aimed at the biologist was however not yet available. Here, we present the Ruby UCSC API, a library to access the UCSC genome database using Ruby. Results The API is designed as a BioRuby plug-in and built on the ActiveRecord 3 framework for the object-relational mapping, making writing SQL statements unnecessary. The current version of the API supports databases of all organisms in the UCSC genome database including human, mammals, vertebrates, deuterostomes, insects, nematodes, and yeast. The API uses the bin index—if available—when querying for genomic intervals. The API also supports genomic sequence queries using locally downloaded *.2bit files that are not stored in the official MySQL database. The API is implemented in pure Ruby and is therefore available in different environments and with different Ruby interpreters (including JRuby). Conclusions Assisted by the straightforward object-oriented design of Ruby and ActiveRecord, the Ruby UCSC API will facilitate biologists to query the UCSC genome database programmatically. The API is available through the RubyGem system. Source code and documentation are available at https://github.com/misshie/bioruby-ucsc-api/ under the Ruby license. Feedback and help is provided via the website at http://rubyucscapi.userecho.com/. PMID:22994508

  11. The Ruby UCSC API: accessing the UCSC genome database using Ruby

    Directory of Open Access Journals (Sweden)

    Mishima Hiroyuki

    2012-09-01

    Full Text Available Abstract Background The University of California, Santa Cruz (UCSC genome database is among the most used sources of genomic annotation in human and other organisms. The database offers an excellent web-based graphical user interface (the UCSC genome browser and several means for programmatic queries. A simple application programming interface (API in a scripting language aimed at the biologist was however not yet available. Here, we present the Ruby UCSC API, a library to access the UCSC genome database using Ruby. Results The API is designed as a BioRuby plug-in and built on the ActiveRecord 3 framework for the object-relational mapping, making writing SQL statements unnecessary. The current version of the API supports databases of all organisms in the UCSC genome database including human, mammals, vertebrates, deuterostomes, insects, nematodes, and yeast. The API uses the bin index—if available—when querying for genomic intervals. The API also supports genomic sequence queries using locally downloaded *.2bit files that are not stored in the official MySQL database. The API is implemented in pure Ruby and is therefore available in different environments and with different Ruby interpreters (including JRuby. Conclusions Assisted by the straightforward object-oriented design of Ruby and ActiveRecord, the Ruby UCSC API will facilitate biologists to query the UCSC genome database programmatically. The API is available through the RubyGem system. Source code and documentation are available at https://github.com/misshie/bioruby-ucsc-api/ under the Ruby license. Feedback and help is provided via the website at http://rubyucscapi.userecho.com/.

  12. Instant RubyMine assimilation

    CERN Document Server

    Jones, Dave

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. Get the job done and learn as you go. A practical guide comprising of easy-to-follow recipes which provide concise and clear steps to help you enter the world of RubyMine.Instant RubyMine is ideal for you, if you are new to RubyMine or well acquainted with the technology. All you need is basic knowledge of writing in Ruby or Ruby on Rails.

  13. Ruby coloured lead glasses by generation of silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Gil, C. [Fundacion Centro Nacional del Vidrio, Pocillo, 1, 40100 La Granja de San Ildefonso (Segovia) (Spain); Villegas, M.A. [Centro Nacional de Investigaciones Metalurgicas (CENIM), Spanish Council for Scientific Research (CSIC), Avda. Gregorio del Amo, 8, 28040 Madrid (Spain)]. E-mail: mavillegas@cenim.csic.es

    2004-11-15

    Both yellow and red superficial ruby lead crystal glasses have been obtained by Ag{sup +} ion-exchange. For red ruby colouring lead glass substrates were previously doped with reducing oxides (arsenic, antimony, cerium and tin). The best experimental conditions for silver ion-exchange were determined. The optical absorption behaviour of the samples was studied to point out the influence of the parameters involved in the ion-exchange process. Moreover, other parameters affecting the final colouring of the glasses (kind of dopant, dopant concentration, etc.) were also analysed. The dopant percentage added to the lead crystal glass is the most important factor for developing superficial red ruby colouring. Antimony oxide doped lead glass ion-exchanged with silver showed the most intense red ruby colouring, even for a doping concentration lower than those of arsenic oxide doped samples able to enhance similar colour. Spectral saturation appeared for the highest doping concentration and for the most severe ion-exchange conditions. Chromatic coordinates were calculated from the corresponding transmission visible spectra. The colour purity showed by the samples obtained satisfies the ornamental requirements that motivated this research.

  14. Rubis: an international strategy; Rubis: une strategie internationale

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-01-01

    In less than 4 years, the Rubis group moved from a role of a regional LPG distributor in North-Eastern France to a multinational company working in Europe, in the Maghreb and along the African East Coast. After a first acquisition in Morocco in 1997 with the setup of Lasfargaz (see article on its mounded storage in this issue), and following the take-over in 1998 and 1999 of IPEM in Italy, the group reinforces its positions in the Peninsula by acquiring Autogaz Meridionale (a marketer representing some 61,000 t/yr). Thus, Italy becomes the first development pole for Rubis. Meanwhile, the group is launching its activities in Madagascar, while stepping ahead in France. Overall, the Rubis group will sell some 500 000 t in 2000. (authors)

  15. Ruby on Rails for dummies

    CERN Document Server

    Burd

    2007-01-01

    Quickly create Web sites with this poweful tool Use this free and easy programming language for e-commerce sites and blogs If you need to build Web and database applications quickly but you don''t dream in computer code, take heart! Ruby on Rails was created for you, and this book will have you up and running in no time. The Ruby scripting language and the Rails framework let you create full-featured Web applications fast. It''s even fun! Discover how toInstall and run Ruby and RailsUse the RadRails IDECreate a blog with RubyConnect your Web site to a databaseBuild a shopping cartExplore Ruby'

  16. Remembering Ruby Special monograph edition: Remembering Ruby

    Directory of Open Access Journals (Sweden)

    Pam Johnson

    2012-05-01

    Full Text Available ‘Remembering Ruby’ is a tribute to Doctor Ruby Langford Ginibi, a remarkable woman and an important Australian writer. Winner of numerous awards for her contribution to literature, as well as to Australian culture, Ruby was an Aboriginal Elder of the Bundjalung nation and a tireless campaigner for the rights of her people. Ruby’s writing is passionate, sincere and heart-felt, as well as extraordinarily funny and articulate. She knew that getting people to listen to her story would be fundamental to naming the hidden history of Indigenous Australia and to changing cultural perceptions in a broader context. As an elder she took on the complex and demanding role of ‘edumacation’, as she called it, and her representations of life and culture continue to provide important reflections, from an Indigenous perspective, on the effects of ignorance, racism and colonisation in an Australian context. As Aboriginal mother, aunty, teacher and scholar her writing represents a particular Australian experience for a readership of people interested in human rights and equality the world over. This monograph, in honouring Ruby Langford Ginibi, is the written expression of an ongoing dialogue between the two authors about their experiences living in Australia and the way that Ruby has interconnected with us and influenced our experiences of growing up in an Australian cultural context. It also brings into focus the many ways that Ruby Langford Ginibi’s writing has been central to challenging and changing prevailing perspectives on the lives of Indigenous people over the last twenty-five years. An excellent communicator with a wicked sense of humour, Ruby’s tireless telling of the truth about the impacts of invasion on Indigenous people makes her an important cultural ambassador for all Australians. Ruby’s totem, the Willy Wagtail, is connected to being a messenger for her people and in writing ‘Remembering Ruby’ we aim to contribute to keeping

  17. Melanosomes are a primary target of Q-switched ruby laser irradiation in guinea pig skin

    Energy Technology Data Exchange (ETDEWEB)

    Polla, L.L.; Margolis, R.J.; Dover, J.S.; Whitaker, D.; Murphy, G.F.; Jacques, S.L.; Anderson, R.R.

    1987-09-01

    The specific targeting of melanosomes may allow for laser therapy of pigmented cutaneous lesions. The mechanism of selective destruction of pigmented cells by various lasers, however, has not been fully clarified. Black, brown, and albino guinea pigs were exposed to optical pulses at various radiant exposure doses from a Q-switched, 40 nsec, 694 nm ruby laser. Biopsies were analyzed by light and electron microscopy (EM). Albino animals failed to develop clinical or microscopic evidence of cutaneous injury after irradiation. In both black and brown animals, the clinical threshold for gross change was 0.4 J/cm2, which produced an ash-white spot. By light microscopy, alterations appeared at 0.3 J/cm2 and included separation at the dermoepidermal junction, and the formation of vacuolated epidermal cells with a peripheral cytoplasmic condensation of pigment. By EM, enlarged melanosomes with a central lucent zone were observed within affected epidermal cells at 0.3 J/cm2. At 0.8 and 1.2 J/cm2, individual melanosomes were more intensely damaged and disruption of melanosomes deep in the hair papillae was observed. Dermal-epidermal blisters were formed precisely at the lamina lucida, leaving basal cell membranes and hemidesmosomes intact. Possible mechanisms for melanosomal injury are discussed. These observations show that the effects of the Q-switched ruby laser are melanin-specific and melanin-dependent, and may be useful in the selective destruction of pigmented as well as superficial cutaneous lesions.

  18. Effect of fusion mixture treatment on the surface of low grade natural ruby

    Energy Technology Data Exchange (ETDEWEB)

    Sakthivel, R., E-mail: velsak_r@yahoo.com; Pradhan, K.C.; Nayak, B.B.; Dash, Tapan; Sahu, R.K.; Mishra, B.K.

    2017-05-01

    Graphical abstract: The colour of low grade natural ruby is enhanced with fusion mixture treatment. Comparative optical absorption and photoluminesence properties of both untreated and treated ruby samples are studied. - Highlights: • Colour of the low grade natural ruby is improved with fusion mixture treatment. • Surface impurities are removed with fusion mixture. • Photoluminescence spectrum of ruby influenced by its Cr{sup 3+} concentration. • X-ray diffraction study confirms the presence of corundum phases in ruby samples. • Treated ruby looks brighter than untreated ruby due to variation in Cr{sup 3+} concentration. - Abstract: Improvement in aesthetic look of low grade natural ruby (gemstone) surface was clearly evident after fusion mixture treatment. Surface impurities of the gemstone were significantly reduced to give it a face lift. The processing consists of heat treatment (1000 °C) of the raw gemstone with fusion mixture (sodium and potassium carbonates), followed by hydrochloric acid digestion (90 °C) and ultrasonic cleaning.Both the untreated and the treated gemstone were characterized by X-ray diffraction, UV–vis spectroscopy (diffuse reflectance),photoluminescence and X-ray photoelectron spectroscopy. The paper consolidates the results of these studies and presents the effect of the typical chemical treatment (stated above) on the low grade natural ruby. While X-ray diffraction study identifies the occurrence of alumina phase in both the treated and the untreated gemstones, the UV–vis spectra exhibit strong characteristic absorption of Cr{sup 3+}at 400 and 550 nm wavelength for the treated gemstone in contrast to weak absorption observed for the untreated gemstone at such wavelengths, thus showing the beneficial effect of fusion mixture treatment. Peaks observed for the gemstone (for both treated and untreated samples) in the excitation spectra of photoluminescence show a good correlation with observed UV–vis (diffuse reflectance

  19. Marble-hosted ruby deposits of the Morogoro Region, Tanzania

    Science.gov (United States)

    Balmer, Walter A.; Hauzenberger, Christoph A.; Fritz, Harald; Sutthirat, Chakkaphan

    2017-10-01

    The ruby deposits of the Uluguru and Mahenge Mts, Morogoro Region, are related to marbles which represent the cover sequence of the Eastern Granulites in Tanzania. In both localities the cover sequences define a tectonic unit which is present as a nappe structure thrusted onto the gneissic basement in a north-western direction. Based on structural geological observations the ruby deposits are bound to mica-rich boudins in fold hinges where fluids interacted with the marble-host rock in zones of higher permeability. Petrographic observations revealed that the Uluguru Mts deposits occur within calcite-dominated marbles whereas deposits in the Mahenge Mts are found in dolomite-dominated marbles. The mineral assemblage describing the marble-hosted ruby deposit in the Uluguru Mts is characterised by corundum-dolomite-phlogopite ± spinel, calcite, pargasite, scapolite, plagioclase, margarite, chlorite, tourmaline whereas the assemblage corundum-calcite-plagioclase-phlogopite ± dolomite, pargasite, sapphirine, titanite, tourmaline is present in samples from the Mahenge Mts. Although slightly different in mineral assemblage it was possible to draw a similar ruby formation history for both localities. Two ruby forming events were distinguished by textural differences, which could also be modeled by thermodynamic T-XCO2 calculations using non-ideal mixing models of essential minerals. A first formation of ruby appears to have taken place during the prograde path (M1) either by the breakdown of diaspore which was present in the original sedimentary precursor rock or by the breakdown of margarite to corundum and plagioclase. The conditions for M1 metamorphism was estimated at ∼750 °C at 10 kbar, which represents granulite facies conditions. A change in fluid composition towards a CO2 dominated fluid triggered a second ruby generation to form. Subsequently, the examined units underwent a late greenschist facies overprint. In the framework of the East African Orogen we

  20. Hello Ruby adventures in coding

    CERN Document Server

    Liukas, Linda

    2015-01-01

    "Code is the 21st century literacy and the need for people to speak the ABCs of Programming is imminent." --Linda Liukas Meet Ruby--a small girl with a huge imagination. In Ruby's world anything is possible if you put your mind to it. When her dad asks her to find five hidden gems Ruby is determined to solve the puzzle with the help of her new friends, including the Wise Snow Leopard, the Friendly Foxes, and the Messy Robots. As Ruby stomps around her world kids will be introduced to the basic concepts behind coding and programming through storytelling. Learn how to break big problems into small problems, repeat tasks, look for patterns, create step-by-step plans, and think outside the box. With hands-on activities included in every chapter, future coders will be thrilled to put their own imaginations to work.

  1. Instant RubyMotion app development

    CERN Document Server

    Laborde, Gant

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. This book is a practical, task-based, step-by-step tutorial that will get you started with using RubyMotion to quickly and efficiently write iOS apps.To make the most of this book, you should understand the basics of programming concepts and have a basic understanding of a language similar to Ruby. If you are an Objective-C programmer, you'll learn the advantages of RubyMotion which can access the benefits of Cocoapods, but takes everything a st

  2. Ruby in a nutshell a desktop quick reference

    CERN Document Server

    Matsumoto, Yukihiro

    2002-01-01

    Ruby is an absolutely pure object-oriented scripting language written in C and designed with Perl and Python capabilities in mind. While its roots are in Japan, Ruby is slowly but surely gaining ground in the US. The goal of Yukihiro Matsumoto, creator of Ruby and author of this book, is to incorporate the strengths of languages like Perl, Python, Lisp and Smalltalk. Ruby is a genuine attempt to combine the best of everything in the scripting world. Since 1993, Ruby mailing lists have been established, Web pages have formed, and a community has grown around it. The language itself is very good at text processing and is notable for its broad object orientation. Ruby is portable and runs under GNU/Linux (and other Unices) as well as DOS, MS Windows and Mac. With Ruby in a Nutshell, Matsumoto offers a practical reference to the features of this new language including the command-line options, syntax, built-in variables, functions, and many commonly used classes and modules. This guide covers the current stable ...

  3. WE-DE-201-10: Pitfalls When Using Ruby as An Inorganic Scintillator Detector for Ir-192 Brachytherapy Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kertzscher, G; Beddar, S [The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: To study the promising potential of inorganic scintillator detectors (ISDs) and investigate various unwanted luminescence properties which may compromise their accuracy. Methods: The ISDs were comprised of a ruby crystal coupled to a polymethyl methacrylate (PMMA) fiber-optic cable and a charged coupled device camera. A new type of ISD was manufactured and included a long-pass filter that was sandwiched between the crystal and the fiber-optic cable. The purpose of the filter was to suppress the Cerenkov and fluorescence background light induced in the PMMA (the stem signal) from striking the ruby crystal, generating unwanted ruby excitation. A variety of experiments were performed to characterize the ruby based ISDs. The relative contribution of the induced ruby signal and the stem signal were quantified while exposing the detector and a bare fiber-optic cable to a high dose rate (HDR) brachytherapy (BT) source, respectively. The unwanted ruby excitation was quantified while irradiating the fiber-optic cable with the detector volume shielded. Other experiments addressed time-dependent luminescence properties and a comparison to other commonly used organic scintillator detectors (BCF-12, BCF-60). Results: When the BT source dwelled 0.5 cm away from the fiber-optic cable, the unwanted ruby excitation amounted to >5% of the total signal if the source-distance from the scintillator was >7 cm. However, the unwanted excitation was suppressed to <1% if the ISD incorporated an optic filter. The stem signal was suppressed with a 20 nm band-pass filter and was <3% as long as the source-distance was <7 cm. The ruby based ISDs generated signal up to 20(40) times that of BCF-12(BCF-60). Conclusion: The study presents solutions to unwanted luminescence properties of ruby based ISDs for HDR BT. An optic filter should be sandwiched between the scintillator volume and the fiber-optic cable to prevent the stem signal to excite the ruby crystal.

  4. Rapid middle Miocene extension and unroofing of the southern Ruby Mountains, Nevada

    Science.gov (United States)

    Colgan, Joseph P.; Howard, Keith A.; Fleck, Robert J.; Wooden, Joseph L.

    2010-01-01

    Paleozoic rocks in the northern Ruby Mountains were metamorphosed during Mesozoic crustal shortening and Cenozoic magmatism, but equivalent strata in the southern Ruby Mountains were never buried deeper than stratigraphic depths prior to exhumation in the footwall of a west dipping brittle normal fault. In the southern Ruby Mountains, Miocene sedimentary rocks in the hanging wall of this fault date from 15.2 to 11.6 Ma and contain abundant detritus from the Paleozoic section. Apatite fission track and (U-Th)/He samples of the Eocene Harrison Pass pluton record rapid cooling that peaked ca. 17–15 Ma, while apatite fission track data from Jurassic plutons east and west of the southern Ruby Mountains indicate near-surface temperatures (pluton to be partially reset rather than to directly record fault slip. Our new data, together with published data on the distribution and composition of Miocene basin fill, suggest that rapid middle Miocene slip took place on the west dipping brittle detachment that bounds the Ruby Mountains and East Humboldt Range for 150 km along strike. This fault was thus active during a period of rapid extension (ca. 17–15 to 12–10 Ma) documented widely across the northern Basin and Range Province.

  5. From Java to Ruby things every manager should know

    CERN Document Server

    Tate, Bruce

    2006-01-01

    As a development team, you want to be productive. You want to write flexible, maintainable web applications. You want to use Ruby and Rails. But can you justify the move away from established platforms such as J2EE? Bruce Tate's From Java to Ruby has the answers, and it expresses them in a language that'll help persuade managers and executives who've seen it all. See when and where the switch makes sense, and see how to make it. If you're trying to adopt Ruby in your organization and need some help, this is the book for you. Based on a decision tree (a concept familiar to managers and executives,) Java to Ruby stays above the low-level technical debate to examine the real benefits and risks to adoption. Java to Ruby is packed with interviews of Ruby customers and developers, so you can see what types of projects are likely to succeed, and which ones are likely to fail. Ruby and Rails may be the answer, but first you need to be sure you're asking the right question. By addressing risk and fitness of purpose, J...

  6. Ion beam analysis of rubies and their simulants

    Energy Technology Data Exchange (ETDEWEB)

    Juncomma, U. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50202 (Thailand); Intarasiri, S., E-mail: saweat@gmail.com [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50202 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Bootkul, D. [Department of General Science (Gems and Jewelry), Faculty of Science, Srinakharinwirot University, Bangkok 10110 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Tippawan, U., E-mail: beary1001@gmail.com [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50202 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2014-07-15

    Ion beam analysis (IBA) is a set of well known powerful analytical techniques which use energetic particle beam as a probe. Among them, two techniques are suitable for gemological analysis, i.e., Particle Induced X-rays Emission (PIXE) and Ionoluminescence (IL). We combine these two techniques for the investigations of rubies and their simulants. The main objective is to find a reference fingerprint of these gemstones. The data are collected from several natural rubies, synthetic rubies, red spinels, almandine garnets and rubellite which very much resemble and are difficult to distinguish with the gemologist loupe. From our measurements, due to their different crystal structures and compositions, can be clearly distinguished by the IL and PIXE techniques. The results show that the PIXE spectra consist of a few dominant lines of the host matrix elements of each gemstone and some weaker lines due to trace elements of transition metals. PIXE can easily differentiate rubies from other stones by evaluating their chemical compositions. It is noticed that synthetic rubies generally contain fewer impurities, lower iron and higher chromium than the natural ones. Moreover, the IL spectrum of ruby is unique and different from those of others stones. The typical spectrum of ruby is centered at 694 nm, with small sidebands that can be ascribed to a Cr{sup 3+} emission spectrum which is dominated by an R-line at the extreme red end of the visible part of the electromagnetic spectrum. Although the spectrum of synthetic ruby is centered at the same wavelength, the peak is stronger due to higher concentration of Cr and lower concentration of Fe than for natural rubies. For spinel, the IL spectrum shows strong deformation where the R-line is split due to the presence of MgO. For rubellite, the peak center is shifted to 692 nm which might be caused by the replacement of Mn{sup 3+} at the Al{sup 3+} site of the host structure. It is noticed that almandine garnet is not luminescent due

  7. Maria Rubies I Garrofe (1932-1993)

    Science.gov (United States)

    Baste, Carme Amoros

    2004-01-01

    This article profiles educator Maria Rubies I Garrofe. Rubies was a woman committed to education and the reconstruction of her country, Spain, equipped solely with the force of her convictions and her faith in dialogue. It is difficult to separate her personal commitment from her educational, social and political commitment. From the very outset…

  8. Hydrogeochemical and stream sediment reconnaissance basic data for Ruby Quadrangle, Alaska

    International Nuclear Information System (INIS)

    1981-01-01

    Field and laboratory data are presented for 693 water samples from the Ruby Quadrangle, Alaska. The samples were collected by Los Alamos National Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

  9. Q-switched ruby laser irradiation of normal human skin. Histologic and ultrastructural findings.

    Science.gov (United States)

    Hruza, G J; Dover, J S; Flotte, T J; Goetschkes, M; Watanabe, S; Anderson, R R

    1991-12-01

    The Q-switched ruby laser is used for treatment of tatoos. The effects of Q-switched ruby laser pulses on sun-exposed and sun-protected human skin, as well as senile lentigines, were investigated with clinical observation, light microscopy, and transmission electron microscopy. A pinpricklike sensation occurred at radiant exposures as low as 0.2 J/cm2. Immediate erythema, delayed edema, and immediate whitening occurred with increasing radiant exposure. The threshold for immediate whitening varied inversely with skin pigmentation, ranging from a mean of 1.4 J/cm2 in lentigines to 3.1 J/cm2 in sun-protected skin. Transmission electron microscopy showed immediate alteration of mature melanosomes and nuclei within keratinocytes and melanocytes, but stage I and II melanosomes were unaffected. Histologically, immediate injury was confined to the epidermis. There was minimal inflammatory response 1 day after exposure. After 1 week, subthreshold exposures induced hyperpigmentation, with epidermal hyperplasia and increased melanin staining noted histologically. At higher radiant exposures, hypopigmentation occurred with desquamation of a pigmented scale/crust. All sites returned to normal skin color and texture without scarring within 3 to 6 months. These observations suggest that the human skin response to selective photothermolysis of pigmented cells is similar to that reported in animal models, including low radiant exposure stimulation of melanogenesis and high radiant exposure lethal injury to pigmented epidermal cells.

  10. Populations of Phytophthora rubi Show Little Differentiation and High Rates of Migration Among States in the Western United States.

    Science.gov (United States)

    Tabima, Javier F; Coffey, Michael D; Zazada, Inga A; Grünwald, Niklaus J

    2018-04-11

    Population genetics is a powerful tool to understand patterns and evolutionary processes that are involved in plant-pathogen emergence and adaptation to agricultural ecosystems. We are interested in studying the population dynamics of Phytophthora rubi, the causal agent of Phytophthora root rot in raspberry. P. rubi is found in the western United States, where most of the fresh and processed raspberries are produced. We used genotyping-by-sequencing to characterize genetic diversity in populations of P. rubi sampled in the United States and other countries. Our results confirm that P. rubi is a monophyletic species with complete lineage sorting from its sister taxon P. fragariae. Overall, populations of P. rubi show low genetic diversity across the western United States. Demographic analyses suggest that populations of P. rubi from the western United States are the source of pathogen migration to Europe. We found no evidence for population differentiation at a global or regional (western United States) level. Finally, our results provide evidence of migration from California and Oregon into Washington. This report provides new insights into the evolution and structure of global and western United States populations of the raspberry pathogen P. rubi, indicating that human activity might be involved in moving the pathogen among regions and fields.

  11. Simply rails 2 the ultimate beginner's guide to Ruby on rails

    CERN Document Server

    Lenz, Patrick

    2008-01-01

    Want to learn all about Ruby on Rails 2.0, the web application framework that is inspiring developers around the world? The second edition of this practical, hands on book will: show you how to install Ruby on Rails on Windows, Mac, or Linux walk you, step by step, through the development of a Web 2.0 social news application, just like digg.com show you how to test, debug, benchmark, and deploy your Rails application Unlike other Rails books, this book doesn't assume that you are an experienced web developer, or that you've used Ruby before. An entire chapter is devoted to learning Ruby in a fun way, using the interactive Ruby console, so you can follow along at home. You'll be an accomplished Ruby programmer in no time! The example application that the book builds - a user-generated news web site - is built upon with each following chapter, and concepts such as sessions, cookies and basic AJAX usage are gradually introduced. Different aspects of Rails, such as user authentication, session cookies, and automa...

  12. Vanadium-rich ruby and sapphire within Mogok Gemfield, Myanmar: implications for gem color and genesis

    Science.gov (United States)

    Zaw, Khin; Sutherland, Lin; Yui, Tzen-Fu; Meffre, Sebastien; Thu, Kyaw

    2015-01-01

    Rubies and sapphires are of both scientific and commercial interest. These gemstones are corundum colored by transition elements within the alumina crystal lattice: Cr3+ yields red in ruby and Fe2+, Fe3+, and Ti4+ ionic interactions color sapphires. A minor ion, V3+ induces slate to purple colors and color change in some sapphires, but its role in coloring rubies remains enigmatic. Trace element and oxygen isotope composition provide genetic signatures for natural corundum and assist geographic typing. Here, we show that V can dominate chromophore contents in Mogok ruby suites. This raises implications for their color quality, enhancement treatments, geographic origin, exploration and exploitation and their comparison with rubies elsewhere. Precise LA-ICP-MS analysis of ruby and sapphire from Mogok placer and in situ deposits reveal that V can exceed 5,000 ppm, giving V/Cr, V/Fe and V/Ti ratios up to 26, 78, and 97 respectively. Such values significantly exceed those found elsewhere suggesting a localized geological control on V-rich ruby distribution. Our results demonstrate that detailed geochemical studies of ruby suites reveal that V is a potential ruby tracer, encourage comparisons of V/Cr-variation between ruby suites and widen the scope for geographic typing and genesis of ruby. This will allow more precise comparison of Asian and other ruby fields and assist confirmation of Mogok sources for rubies in historical and contemporary gems and jewelry.

  13. Ion irradiation effect of alumina and its luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Yasushi; Yamamoto, Shunya; Naramoto, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; My, N T

    1997-03-01

    The luminescence spectra of single crystalline alpha-alumina and ruby which has 0.02% of Cr{sub 2}O{sub 3} as a impurity, induced by 200 keV He{sup +} and Ar{sup +} irradiation were measured at room temperature as a function of irradiation dose. The analysis of the measured spectra showed the existence of three main luminescence features in the wavelength region of 250 to 350 nm, namely anionic color centers, F-center at 411 nm and F{sup +}-center at 330 nm and a band observed around 315 nm. As alpha-alumina was irradiated with He{sup +}, F-center and F{sup +}-center luminescence grew and decayed, but the behaviors of those were different from each other. It seems that a concentration quenching occurred on the F-center luminescence in the dose range above 1x10{sup 14} He/cm{sup 2}. Furthermore, F-center luminescence was strongly suppressed in ruby, compared with that in alumina. On the other hand, the luminescence band around 315 nm appeared only in the early stage of irradiation and did not show its growth part. The dose dependent behavior was similar to that of Cr{sup 3+} emission at 695 nm (R-line) in ruby in both cases of He{sup +} and Ar{sup +} irradiation. Based on the experimental results mentioned above, the processes of defect formation and excitation in alumina in the early stage of ion irradiation will be discussed. (author)

  14. Practical reporting with Ruby and Rails

    CERN Document Server

    Berube, David

    2008-01-01

    Business intelligence and real time reporting mechanisms play a major role in any of today s forward looking business plans. With many of these solutions being moved to the Web, the popular Rails framework and its underlying Ruby language are playing a major role alongside web services in building the reporting solutions of tomorrow. Practical Reporting with Ruby and Rails is the first book to comprehensively introduce this popular framework, guiding readers through a wide ranging array of features. Note this isn t a staid guide to generating traditional reports, but rather it shows you how th

  15. Rubis on the move; Progression de Rubis

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1999-10-01

    Purchase in June of IPEM'S remnant parts (50%) in Italy, acquisition today of an Italian marketer (30,000 t per year), a distribution bought in Madagascar, the upcoming installation of 3 large mounted tanks at Jorf Lasfar (Morocco), an impressive growth of its GAZ'L automotive LP Gas network in commercial centers in France, a good growth in mini-bulk and creation of a 'Customer Care Center' by Vitogaz's headquarters. Such are the achievements announced by the Rubis group, along with the presentation of its good results for the first half of the year. (authors)

  16. Trace element fingerprinting of jewellery rubies by external beam PIXE

    International Nuclear Information System (INIS)

    Calligaro, T.; Poirot, J.-P.; Querre, G.

    1999-01-01

    External beam PIXE analysis allows the non-destructive in situ characterisation of gemstones mounted on jewellery pieces. This technique was used for the determination of the geographical origin of 64 rubies set on a high-valued necklace. The trace element content of these gemstones was measured and compared to that of a set of rubies of known sources. Multivariate statistical processing of the results allowed us to infer the provenance of rubies: one comes from Thailand/Cambodia deposit while the remaining are attributed to Burma. This highlights the complementary capabilities of PIXE and conventional geological observations

  17. Trace element fingerprinting of jewellery rubies by external beam PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Calligaro, T. E-mail: calli@culture.nl; Poirot, J.-P.; Querre, G

    1999-04-02

    External beam PIXE analysis allows the non-destructive in situ characterisation of gemstones mounted on jewellery pieces. This technique was used for the determination of the geographical origin of 64 rubies set on a high-valued necklace. The trace element content of these gemstones was measured and compared to that of a set of rubies of known sources. Multivariate statistical processing of the results allowed us to infer the provenance of rubies: one comes from Thailand/Cambodia deposit while the remaining are attributed to Burma. This highlights the complementary capabilities of PIXE and conventional geological observations.

  18. Methods for Detection of Phytophthora fragariae var. rubi on Raspberry

    Directory of Open Access Journals (Sweden)

    Mirjana Koprivica

    2009-01-01

    Full Text Available Phytophthora fragariae var. rubi (Wilcox & Duncan, a causal agent of raspberry root rot, is a serious soil-borne pathogen listed by EPPO as an A2 quarantine pest. Root samples were collected from badly diseased raspberry plants showing a variety of characteristic and often dramatic symptoms during surveys carried out in western Serbia in 2002. Identification of the causal agent was performed in collaboration work with the Scottish Crop Research Institute (S.C.R.I., Dundee, UK. Necrotic roots were plated on selective French bean agar (incorporating ampicilin, ryfamicin, bavistin and hymexasol. Detection of isolates was based on cultural and morphological features compared with referent cultures. DNA was extracted directly from the sampled roots using extraction buffer (200 mM Tris- HCl pH 8.5, 250 mM NaCl, 25 mM EDTA, 0.5% SDS, purified by multi spin separation columns [Thistle Scientific (Axygen] or in 24:1 mixture of chlorophorm- iso-amyl alcohol and amplified by nested PCR (ITS4 and DC6 for first round, DC1and DC5 for second round. Diluted DNA extracts were also amplified by conventional PCR with modified ”universal” Phytophthora primers (ITS 6, ITS 7 and ITS 8, Cooke et al., 2000 and digested with Msp1. Digestion patterns of the universal primers PCR product from infected roots matched those of Scottish strains. P. fragariae var. rubi occured on 8 out of 14 sites. Our results indicate that nested PCR (ITS4 and DC6 for first round, DC1 and DC5 for second round or digestion of the ”universal” Phytophthora primers PCR product for detection of P. fragariae var. rubi are more sensitive and less time-consuming and therefore recommended for use.

  19. Scientific legacy of Stanley Ruby

    International Nuclear Information System (INIS)

    Shenoy, G. K.

    2006-01-01

    Stanley L. Ruby (1924-2004) made major contributions to Moessbauer spectroscopy and was the first to suggest the feasibility of observing the Moessbauer effect using synchrotron radiation. In this article we recall his scientific legacy that have inspired his scientific colleagues.

  20. Study of the photo and cathodoluminescent properties of the rubi

    International Nuclear Information System (INIS)

    Martinez S, E.; Garcia H, M.; Ramos B, F.; Alvarez F, O.; Rivera M, T.; Azorin N, J.; Falcony G, C.

    1999-01-01

    In this work are presented the results of the study of the photoluminescence and cathodoluminescence properties of the rubi analysing its use in radiation dosimetry. The rubi presented a centered emission spectra in 697 nm when this was excited with UV at a wavelength 364 nm. X-ray analysis show a rhombohedric structure. While the analysis performed by EDS was obtained the composition (O= 63.13, Al= 36.75 and Cr= 0.12) weight percent, the cathodoluminescent spectra presented three peaks at 555, 600 and 630 nm, being the peak or maximum emission the 600 nm. The results showed the rubi is a promissory material for the radiations dosimetry. (Author)

  1. Bistable direction switching in an off-axis pumped continuous wave ruby laser

    Science.gov (United States)

    Afzal, R. Sohrab; Lawandy, N. M.

    1988-01-01

    A report is presented of the observation of hysteretic bistable direction switching in a single-mode CW ruby laser system. This effect is only observed when the pump beam which is focused into the ruby rod is misaligned with respect to the rod end faces. At low pump powers, the ruby lases in a mode nearly collinear with the pump axis. At a higher pump power the ruby switches to a mode that is collinear with the rod end faces and preserves the original polarization. The effect is large enough to switch the beam by an angle equal to twice the diffraction angle. The observations show that under steady-state pumping, a CW ruby laser can exhibit bistable operation in its output direction and power. A calculation using the heat equation with two concentric cylinders with one as a heat source (pump laser) and the outer wall of the other held at 77 K, gives an increase in core temperature of about 0.01 K. Therefore, the increase in temperature is not large enough to change the index of refraction to account for such large macroscopic effects.

  2. Ruby laser for treatment of tattoos: technical considerations affecting clinical use

    Science.gov (United States)

    Grove, Robert E.

    1990-06-01

    Recent clinical research on the use of ruby lasers for the treatment of tattoos and FIlk approval of a commercial system have renewed interest in this device. In this paper the principles of Q-switched ruby laser operation are reviewed, and potential sources of error in the estimation of delivered fluence are discussed.

  3. A Ruby API to query the Ensembl database for genomic features.

    Science.gov (United States)

    Strozzi, Francesco; Aerts, Jan

    2011-04-01

    The Ensembl database makes genomic features available via its Genome Browser. It is also possible to access the underlying data through a Perl API for advanced querying. We have developed a full-featured Ruby API to the Ensembl databases, providing the same functionality as the Perl interface with additional features. A single Ruby API is used to access different releases of the Ensembl databases and is also able to query multi-species databases. Most functionality of the API is provided using the ActiveRecord pattern. The library depends on introspection to make it release independent. The API is available through the Rubygem system and can be installed with the command gem install ruby-ensembl-api.

  4. Gamma radiation induced cytological abnormalities in Lycopersicon esculentum Mill. var. pusa ruby

    Energy Technology Data Exchange (ETDEWEB)

    Jayabalan, N.; Rao, G.R.

    1987-03-01

    Healthy dry seeds of pusa ruby variety of Lycopersicon esculentum Mill. were irradiated with gamma rays at 10 KR, 20 KR, 30 KR, 40 KR and 50 KR dose levels. Meiotic studies were made in treated plants as well as in control plants. At metaphase I, meiotic abnormalities like clumping and stickiness of chromosomes, univalents, multivalents, fragments and irregular grouping of chromosomes were observed. At anaphase I, there were laggards and unequal grouping of chromosomes at poles. Germination percentage and pollen fertility were also studied. Pollen sterility seems to be the cumulative result of various abnormal meiotic stages as well as of physiological and genetic damages induced probably by breakage of chromosomes. The frequency of meiotic abnormalities with reference to the effect of radiation doses is discussed.

  5. N and Cr ion implantation of natural ruby surfaces and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Rao, K. Sudheendra; Sahoo, Rakesh K.; Dash, Tapan [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar 751013 (India); Magudapathy, P.; Panigrahi, B.K. [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Nayak, B.B.; Mishra, B.K. [CSIR-Institute of Minerals and Materials Technology, Bhubaneswar 751013 (India)

    2016-04-15

    Highlights: • Cr and N ion implantation on natural rubies of low aesthetic quality. • Cr-ion implantation improves colour tone from red to deep red (pigeon eye red). • N-ion implantation at fluence of 3 × 10{sup 17} causes blue coloration on surface. • Certain extent of amorphization is observed in the case of N-ion implantation. - Abstract: Energetic ions of N and Cr were used to implant the surfaces of natural rubies (low aesthetic quality). Surface colours of the specimens were found to change after ion implantation. The samples without and with ion implantation were characterized by diffuse reflectance spectra in ultra violet and visible region (DRS-UV–Vis), field emission scanning electron microscopy (FESEM), selected area electron diffraction (SAED) and nano-indentation. While the Cr-ion implantation produced deep red surface colour (pigeon eye red) in polished raw sample (without heat treatment), the N-ion implantation produced a mixed tone of dark blue, greenish blue and violet surface colour in the heat treated sample. In the case of heat treated sample at 3 × 10{sup 17} N-ions/cm{sup 2} fluence, formation of colour centres (F{sup +}, F{sub 2}, F{sub 2}{sup +} and F{sub 2}{sup 2+}) by ion implantation process is attributed to explain the development of the modified surface colours. Certain degree of surface amorphization was observed to be associated with the above N-ion implantation.

  6. A short history of RubisCO: the rise and fall (?) of Nature's predominant CO2 fixing enzyme.

    Science.gov (United States)

    Erb, Tobias J; Zarzycki, Jan

    2018-02-01

    Ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) is arguably one of the most abundant proteins in the biosphere and a key enzyme in the global carbon cycle. Although RubisCO has been intensively studied, its evolutionary origins and rise as Nature's most dominant carbon dioxide (CO 2 )-fixing enzyme still remain in the dark. In this review we will bring together biochemical, structural, physiological, microbiological, as well as phylogenetic data to speculate on the evolutionary roots of the CO 2 -fixation reaction of RubisCO, the emergence of RubisCO-based autotrophic CO 2 -fixation in the context of the Calvin-Benson-Bassham cycle, and the further evolution of RubisCO into the 'RubisCOsome', a complex of various proteins assembling and interacting with the enzyme to improve its operational capacity (functionality) under different biological and environmental conditions. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Aesthetic value improvement of the ruby stone using heat treatment and its synergetic surface study

    International Nuclear Information System (INIS)

    Sahoo, Rakesh K.; Mohapatra, Birendra K.; Singh, Saroj K.; Mishra, Barada K.

    2015-01-01

    Highlights: • Natural ruby is heated at high temperature with metal oxide additives (PbO and ZnO) to enhance its aesthetic value. • Changes in surface characteristics of these natural rubies before and after heat treatment are compared. • The R-line peak splitting in the PL spectra and the contrary shift of the Al 2p peaks in the XPS spectra are explicated. - Abstract: The surface behavior of the natural ruby stones before and after heat treatment with metal oxide additives like: zinc oxide (ZnO) and lead oxide (PbO) have been studied. The surface appearance of the ruby stones processed with the metal oxides changed whereas the bulk densities of the stones remained within the range of 3.9–4.0 g/cm 3 . The cracks healing and pores filling by the metal oxides on the surface of the ruby have been examined using scanning electron microscopy. The chemical compositions based on the XPS survey scans are in good agreement with the expected composition. The phase and crystallinity of the ruby stones original and heat-treated were obtained from their X-ray diffraction patterns. The change in peak separation between R 1 and R 2 – peaks in photoluminescence spectra and the contrary binding energy shift of the Al 2p peaks in the X-ray photoelectron spectra have been explicated. Moreover, in this work we describe the change in surface chemical and physical characteristics of the ruby stone before and after heat treatment

  8. Gamma radiation induced cytological abnormalities in Lycopersicon esculentum Mill. var. pusa ruby

    International Nuclear Information System (INIS)

    Jayabalan, N.; Rao, G.R.

    1987-01-01

    Healthy dry seeds of pusa ruby variety of Lycopersicon esculentum Mill. were irradiated with gamma rays at 10 KR, 20 KR, 30 KR, 40 KR and 50 KR dose levels. Meiotic studies were made in treated plants as well as in control plants. At metaphase I, meiotic abnormalities like clumping and stickiness of chromosomes, univalents, multivalents, fragments and irregular grouping of chromosomes were observed. At anaphase I, there were laggards and unequal grouping of chromosomes at poles. Germination percentage and pollen fertility were also studied. Pollen sterility seems to be the cumulative result of various abnormal meiotic stages as well as of physiological and genetic damages induced probably by breakage of chromosomes. The frequency of meiotic abnormalities with reference to the effect of radiation doses is discussed. (author)

  9. Mr.CAS-A minimalistic (pure) Ruby CAS for fast prototyping and code generation

    Science.gov (United States)

    Ragni, Matteo

    There are Computer Algebra System (CAS) systems on the market with complete solutions for manipulation of analytical models. But exporting a model that implements specific algorithms on specific platforms, for target languages or for particular numerical library, is often a rigid procedure that requires manual post-processing. This work presents a Ruby library that exposes core CAS capabilities, i.e. simplification, substitution, evaluation, etc. The library aims at programmers that need to rapidly prototype and generate numerical code for different target languages, while keeping separated mathematical expression from the code generation rules, where best practices for numerical conditioning are implemented. The library is written in pure Ruby language and is compatible with most Ruby interpreters.

  10. Mr.CAS—A minimalistic (pure Ruby CAS for fast prototyping and code generation

    Directory of Open Access Journals (Sweden)

    Matteo Ragni

    2017-01-01

    Full Text Available There are Computer Algebra System (CAS systems on the market with complete solutions for manipulation of analytical models. But exporting a model that implements specific algorithms on specific platforms, for target languages or for particular numerical library, is often a rigid procedure that requires manual post-processing. This work presents a Ruby library that exposes core CAS capabilities, i.e. simplification, substitution, evaluation, etc. The library aims at programmers that need to rapidly prototype and generate numerical code for different target languages, while keeping separated mathematical expression from the code generation rules, where best practices for numerical conditioning are implemented. The library is written in pure Ruby language and is compatible with most Ruby interpreters.

  11. Improvements of the ruby laser oscillator system for laser scattering

    International Nuclear Information System (INIS)

    Yamauchi, Toshihiko; Kumagai, Katsuaki; Kawakami, Tomohide; Matoba, Tohru; Funahashi, Akimasa

    1978-10-01

    A ruby laser oscillator system is used to measure electron temperatures of the Tokamak plasmas(JFT-2 and JFT-2a). Improvements have been made of the laser oscillator to obtain the correct values. Described are the improvements and the damages of a ruby rod and a KD*P crystal for Q-switching by laser beam. Improvement are the linear Xe lamp replaced by a helical Xe lamp and in the electrical circuit for Q-switching. The damage of an optical component by a laser beam should be clarified from the damage data; the cause is not found yet. (author)

  12. Advances in Trace Element “Fingerprinting” of Gem Corundum, Ruby and Sapphire, Mogok Area, Myanmar

    Directory of Open Access Journals (Sweden)

    F. Lin Sutherland

    2014-12-01

    Full Text Available Mogok gem corundum samples from twelve localities were analyzed for trace element signatures (LA-ICP-MS method and oxygen isotope values (δ18O, by laser fluorination. The study augmented earlier findings on Mogok gem suites that suggested the Mogok tract forms a high vanadium gem corundum area and also identified rare alluvial ruby and sapphire grains characterised by unusually high silicon, calcium and gallium, presence of noticeable boron, tin and niobium and very low iron, titanium and magnesium contents. Oxygen isotope values (δ18O for the ruby and high Si-Ca-Ga corundum (20‰–25‰ and for sapphire (10‰–20‰ indicate typical crustal values, with values >20‰ being typical of carbonate genesis. The high Si-Ca-Ga ruby has high chromium (up to 3.2 wt % Cr and gallium (up to 0. 08 wt % Ga compared to most Mogok ruby (<2 wt % Cr; <0.02 wt % Ga. In trace element ratio plots the Si-Ca-Ga-rich corundum falls into separate fields from the typical Mogok metamorphic fields. The high Ga/Mg ratios (46–521 lie well within the magmatic range (>6, and with other features suggest a potential skarn-like, carbonate-related genesis with a high degree of magmatic fluid input The overall trace element results widen the range of different signatures identified within Mogok gem corundum suites and indicate complex genesis. The expanded geochemical platform, related to a variety of metamorphic, metasomatic and magmatic sources, now provides a wider base for geographic typing of Mogok gem corundum suites. It allows more detailed comparisons with suites from other deposits and will assist identification of Mogok gem corundum sources used in jewelry.

  13. Ruby-Helix: an implementation of helical image processing based on object-oriented scripting language.

    Science.gov (United States)

    Metlagel, Zoltan; Kikkawa, Yayoi S; Kikkawa, Masahide

    2007-01-01

    Helical image analysis in combination with electron microscopy has been used to study three-dimensional structures of various biological filaments or tubes, such as microtubules, actin filaments, and bacterial flagella. A number of packages have been developed to carry out helical image analysis. Some biological specimens, however, have a symmetry break (seam) in their three-dimensional structure, even though their subunits are mostly arranged in a helical manner. We refer to these objects as "asymmetric helices". All the existing packages are designed for helically symmetric specimens, and do not allow analysis of asymmetric helical objects, such as microtubules with seams. Here, we describe Ruby-Helix, a new set of programs for the analysis of "helical" objects with or without a seam. Ruby-Helix is built on top of the Ruby programming language and is the first implementation of asymmetric helical reconstruction for practical image analysis. It also allows easier and semi-automated analysis, performing iterative unbending and accurate determination of the repeat length. As a result, Ruby-Helix enables us to analyze motor-microtubule complexes with higher throughput to higher resolution.

  14. Teaching Financial Literacy with Max and Ruby

    Science.gov (United States)

    Brown, Natalya; Ferguson, Kristen

    2017-01-01

    Teaching financial literacy is important at all stages of life, but is often neglected with elementary students. In this article, the authors describe a strategy for teaching financial literacy using the books about Max and Ruby by Rosemary Wells. These books can help introduce the five key concepts of financial literacy: scarcity, exchange,…

  15. Irradiation chamber and sample changer for biological samples

    International Nuclear Information System (INIS)

    Kraft, G.; Daues, H.W.; Fischer, B.; Kopf, U.; Liebold, H.P.; Quis, D.; Stelzer, H.; Kiefer, J.; Schoepfer, F.; Schneider, E.

    1980-01-01

    This paper describes an irradiaton system with which living cells of different origin are irradiated with heavy ion beams (18 <- Z <- 92) at energies up to 10 MeV/amu. The system consists of a beam monitor connected to the vacuum system of the accelerator and the irradiation chamber, containing the biological samples under atmospheric pressure. The requirements and aims of the set up are discussed. The first results with saccharomyces cerevisiae and Chinese Hamster tissue cells are presented. (orig.)

  16. Unusual ruby-sapphire transition in alluvial megacrysts, Cenozoic basaltic gem field, New England, New South Wales, Australia

    Science.gov (United States)

    Sutherland, Frederick L.; Graham, Ian T.; Harris, Stephen J.; Coldham, Terry; Powell, William; Belousova, Elena A.; Martin, Laure

    2017-05-01

    Rare ruby crystals appear among prevailing sapphire crystals mined from placers within basaltic areas in the New England gem-field, New South Wales, Australia. New England ruby (NER) has distinctive trace element features compared to those from ruby elsewhere in Australia and indeed most ruby from across the world. The NER suite includes ruby (up to 3370 ppm Cr), pink sapphire (up to 1520 ppm Cr), white sapphire (up to 910 ppm) and violet, mauve, purple, or bluish sapphire (up to 1410 ppm Cr). Some crystals show outward growth banding in this respective colour sequence. All four colour zones are notably high in Ga (up to 310 ppm) and Si (up to 1820 ppm). High Ga and Ga/Mg values are unusual in ruby and its trace element plots (laser ablation-inductively coupled plasma-mass spectrometry) and suggests that magmatic-metasomatic inputs were involved in the NER suite genesis. In situ oxygen isotope analyses (secondary ion mass spectrometry) across the NER suite colour range showed little variation (n = 22; δ18O = 4.4 ± 0.4, 2σ error), and are values typical for corundum associated with ultramafic/mafic rocks. The isolated NER xenocryst suite, corroded by basalt transport and with few internal inclusions, presents a challenge in deciphering its exact origin. Detailed consideration of its high Ga chemistry in relation to the known geology of the surrounding region was used to narrow down potential sources. These include Late Palaeozoic-Triassic fractionated I-type granitoid magmas or Mesozoic-Cenozoic felsic fractionates from basaltic magmas that interacted with early Palaeozoic Cr-bearing ophiolite bodies in the New England Orogen. Other potential sources may lie deeper within lower crust-mantle metamorphic assemblages, but need to match the anomalous high-Ga geochemistry of the New England ruby suite.

  17. Influence of chromium concentration on the optical-electronic properties of ruby microstructures

    International Nuclear Information System (INIS)

    Cossolino, L C; Zanatta, A R

    2010-01-01

    Films of amorphous aluminium nitride (AlN) were prepared by conventional radio frequency sputtering of an Al + Cr target in a plasma of pure nitrogen. The Cr-to-Al relative area determines the Cr content, which remained in the ∼0-3.5 at% concentration range in this study. Film deposition was followed by thermal annealing of the samples up to 1050 0 C in an atmosphere of oxygen and by spectroscopic characterization through energy dispersive x-ray spectrometry, photoluminescence and optical transmission measurements. According to the experimental results, the optical-electronic properties of the Cr-containing AlN films are highly influenced by both the Cr concentration and the temperature of the thermal treatments. In fact, thermal annealing at 1050 0 C induces the development of structures that, because of their typical size and distinctive spectral characteristics, were designated by ruby microstructures (RbMSs). These RbMSs are surrounded by a N-rich environment in which Cr 3+ ions exhibit luminescent features not present in other Cr 3+ -containing systems such as ruby, emerald or alexandrite. The light emissions shown by the RbMSs and surroundings were investigated according to the Cr concentration and temperature of measurement, allowing the identification of several Cr 3+ -related luminescent lines. The main characteristics of these luminescent lines and corresponding excitation-recombination processes are presented and discussed in view of a detailed spectroscopic analysis.

  18. Bistable polarization switching in a continuous wave ruby laser

    Science.gov (United States)

    Lawandy, N. M.; Afzal, R. Sohrab

    1988-01-01

    Bistability in the output power, polarization state, and mode volume of an argon-ion laser pumped single mode ruby laser at 6943 A has been observed. The laser operates in a radially confined mode which exhibits hysteresis and bistability only when the pump polarization is parallel to the c-axis.

  19. Under the Radar: The First Woman in Radio Astronomy, Ruby Payne-Scott

    Science.gov (United States)

    Miller Goss, W.

    2012-05-01

    Under the Radar, the First Woman in Radio Astronomy, Ruby Payne-Scott W. Miller Goss, NRAO Socorro NM Ruby Payne-Scott (1912-1981) was an eminent Australian scientist who made major contributions to the WWII radar effort (CSIR) from 1941 to 1945. In late 1945, she pioneered radio astronomy efforts at Dover Heights in Sydney, Australia at a beautiful cliff top overlooking the Tasman Sea. Again at Dover Heights, Payne-Scott carried out the first interferometry in radio astronomy using an Australian Army radar antenna as a radio telescope at sun-rise, 26 January 1946. She continued these ground breaking activities until 1951. Ruby Payne-Scott played a major role in discovering and elucidating the properties of Type III bursts from the sun, the most common of the five classes of transient phenomena from the solar corona. These bursts are one of the most intensively studied forms of radio emission in all of astronomy. She is also one of the inventors of aperture synthesis in radio astronomy. I examine her career at the University of Sydney and her conflicts with the CSIR hierarchy concerning the rights of women in the work place, specifically equal wages and the lack of permanent status for married women. I also explore her membership in the Communist Party of Australia as well as her partially released Australian Scientific Intelligence Organization file. Payne-Scott’s role as a major participant in the flourishing radio astronomy research of the post war era remains a remarkable story. She had a number of strong collaborations with the pioneers of early radio astronomy in Australia: Pawsey, Mills, Christiansen, Bolton and Little. I am currently working on a popular version of the Payne-Scott story; “Making Waves, The Story of Ruby Payne-Scott: Australian Pioneer Radio Astronomer” will be published in 2013 by Springer in the Astronomers’ Universe Series.

  20. Citrus asymmetric somatic hybrids produced via fusion of gamma-irradiated and iodoacetamide-treated protoplasts

    Energy Technology Data Exchange (ETDEWEB)

    Bona, Claudine Maria de [Instituto Agronomico do Parana (IAPAR), Curitiba, PR (Brazil)], e-mail: debona@iapar.br; Gould, Jean Howe [Texas A and M University, College Station, TX (United States). Dept. of Ecosystem Science and Management], e-mail: gould@tamu.edu; Miller Junior, J. Creighton [Texas A and M University, College Station, TX (United States). Dept. of Horticultural Sciences], e-mail: jcmillerjr@tamu.edu; Stelly, David [Texas A and M University, College Station, TX (United States). Dept. of Soil and Crop Sciences], e-mail: stelly@tamu.edu; Louzada, Eliezer Silva [Texas A and M University, Kingsville, TX (United States). Citrus Center], e-mail: e-louzada@tamu.edu

    2009-05-15

    The objective of this study was to produce citrus somatic asymmetric hybrids by fusing gamma.irradiated protoplasts with iodoacetamide-treated protoplasts. Protoplasts were isolated from embryogenic suspension cells of grapefruit (Citrus paradisi Macfad.) cultivars Ruby Red and Flame, sweet oranges (C. sinensis Osbeck) 'Itaborai', 'Natal', Valencia', and 'Succari', from 'Satsuma' (C. unshiu Marcow.) and 'Changsha' mandarin (C. reticulata Blanco) and 'Murcott' tangor (C. reticulata x C. sinensis). Donor protoplasts were exposed to gamma rays and receptor protoplasts were treated with 3 mmol L{sup -1} iodoacetamide (IOA), and then they were fused for asymmetric hybridization. Asymmetric embryos were germinated, and the resulting shoots were either grafted onto sour orange, rough lemon or 'Swingle' (C. paradisi x Poncirus trifoliata) x 'Sunki' mandarin rootstock seedlings, or rooted after dipping their bases in indol.butyric acid (IBA) solution. The products were later acclimatized to greenhouse conditions. Ploidy was analyzed by flow cytometry, and hybridity was confirmed by amplified fragment length polymorphism (AFLP) analysis of plantlet DNA samples. The best treatment was the donor-recipient fusion combination of 80 Gy.irradiated 'Ruby Red' protoplasts with 20 min IOA.treated 'Succari' protoplasts. Tetraploid and aneuploid plants were produced. Rooting recalcitrance was solved by dipping shoots' stems in 3,000 mg L{sup -1} IBA solution for 10 min. (author)

  1. Sand dune of Ruby, Arizona, an anthropogenically created biodiversity hotspot for wasps and their velvet ant parasitoids

    Science.gov (United States)

    Justin O. Schmidt

    2013-01-01

    A large artificial sand dune composed of finely crushed mine tailings was produced by deep mining operations at Ruby, Arizona. Today, the ghost town of Ruby is an important historical location and biodiversity refuge, with the newly formed dune forming the core of the refuge. The dune provides ideal nesting habitat for at least 13 species of sand-loving wasps,...

  2. Sampling by electro-erosion on irradiated materials

    International Nuclear Information System (INIS)

    Riviere, M.; Pizzanelli, J.P.

    1986-05-01

    Sampling on irradiated materials, in particular for mechanical property study of steels in the FAST NEUTRON program needed the set in a hot cell of a machining device by electroerosion. This device allows sampling of tenacity, traction, resilience test pieces [fr

  3. Comparison of pulsed electron beam-annealed and pulsed ruby laser-annealed ion-implanted silicon

    International Nuclear Information System (INIS)

    Wilson, S.R.; Appleton, B.R.; White, C.W.; Narayan, J.; Greenwald, A.C.

    1978-11-01

    Recently two new techniques, pulsed electron beam annealing and pulsed laser annealing, have been developed for processing ion-implanted silicon. These two types of anneals have been compared using ion-channeling, ion back-scattering, and transmission electron microscopy (TEM). Single crystal samples were implanted with 100 keV As + ions to a dose of approx. 1 x 10 16 ions/cm 2 and subsequently annealed by either a pulsed Ruby laser or a pulsed electron beam. Our results show in both cases that the near-surface region has melted and regrown epitaxially with nearly all of the implanted As (97 to 99%) incroporated onto lattice sites. The analysis indicates that the samples are essentially defect free and have complete electrical recovery

  4. Visuaalantropoloogia - inimlik mõõde asjade maailmas / Jay Ruby ; interv. Peeter Linnap

    Index Scriptorium Estoniae

    Ruby, Jay

    2006-01-01

    Ameerika visuaalkultuuri teoreetik Jay Ruby on paari viimase aastakümne jooksul keskendunud pildilise kommunikatsiooni etnograafilisele käsitlemisele Ameerika maaühiskonnas. Peeter Linnapi intervjuu Jay Rubyga Tartu Kõrgemas Kunstikoolis 23. V

  5. Hall effect measurements on proton-irradiated ROSE samples

    International Nuclear Information System (INIS)

    Biggeri, U.; Bruzzi, M.; Borchi, E.

    1997-01-01

    Bulk samples obtained from two wafers of a silicon monocrystal material produced by Float-Zone refinement have been analyzed using the four-point probe method. One of the wafers comes from an oxygenated ingot; two sets of pure and oxygenated samples have been irradiated with 24 GeV/c protons in the fluence range from 10 13 p/cm 2 to 2x10 14 p/cm 2 . Van der Pauw resistivity and Hall coefficient have been measured before and after irradiation as a function of the temperature. A thermal treatment (30 minutes at 100C) has been performed to accelerate the reverse annealing effect in the irradiated silicon. The irradiated samples show the same exponential dependence of the resistivity and of the Hall coefficient on the temperature from 370K to 100K, corresponding to the presence of radiation-induced deep energy levels around 0.6-0.7eV in the silicon gap. The free carrier concentrations (n, p) have been evaluated in the investigated fluence range. The inversion of the conductivity type from n to p occurred respectively at 7x10 13 p/cm 2 and at 4x10 13 p/cm 2 before and after the annealing treatment, for both the two sets. Only slight differences have been detected between the pure and oxygenated samples

  6. Calcium rubies: a family of red-emitting functionalizable indicators suitable for two-photon Ca2+ imaging.

    Science.gov (United States)

    Collot, Mayeul; Loukou, Christina; Yakovlev, Aleksey V; Wilms, Christian D; Li, Dongdong; Evrard, Alexis; Zamaleeva, Alsu; Bourdieu, Laurent; Léger, Jean-François; Ropert, Nicole; Eilers, Jens; Oheim, Martin; Feltz, Anne; Mallet, Jean-Maurice

    2012-09-12

    We designed Calcium Rubies, a family of functionalizable BAPTA-based red-fluorescent calcium (Ca(2+)) indicators as new tools for biological Ca(2+) imaging. The specificity of this Ca(2+)-indicator family is its side arm, attached on the ethylene glycol bridge that allows coupling the indicator to various groups while leaving open the possibility of aromatic substitutions on the BAPTA core for tuning the Ca(2+)-binding affinity. Using this possibility we now synthesize and characterize three different CaRubies with affinities between 3 and 22 μM. Their long excitation and emission wavelengths (peaks at 586/604 nm) allow their use in otherwise challenging multicolor experiments, e.g., when combining Ca(2+) uncaging or optogenetic stimulation with Ca(2+) imaging in cells expressing fluorescent proteins. We illustrate this capacity by the detection of Ca(2+) transients evoked by blue light in cultured astrocytes expressing CatCh, a light-sensitive Ca(2+)-translocating channelrhodopsin linked to yellow fluorescent protein. Using time-correlated single-photon counting, we measured fluorescence lifetimes for all CaRubies and demonstrate a 10-fold increase in the average lifetime upon Ca(2+) chelation. Since only the fluorescence quantum yield but not the absorbance of the CaRubies is Ca(2+)-dependent, calibrated two-photon fluorescence excitation measurements of absolute Ca(2+) concentrations are feasible.

  7. Electron beam physical vapor deposition of thin ruby films for remote temperature sensing

    International Nuclear Information System (INIS)

    Li Wei; Coppens, Zachary J.; Greg Walker, D.; Valentine, Jason G.

    2013-01-01

    Thermographic phosphors (TGPs) possessing temperature-dependent photoluminescence properties have a wide range of uses in thermometry due to their remote access and large temperature sensitivity range. However, in most cases, phosphors are synthesized in powder form, which prevents their use in high resolution micro and nanoscale thermal microscopy. In the present study, we investigate the use of electron beam physical vapor deposition to fabricate thin films of chromium-doped aluminum oxide (Cr-Al 2 O 3 , ruby) thermographic phosphors. Although as-deposited films were amorphous and exhibited weak photoluminescence, the films regained the stoichiometry and α-Al 2 O 3 crystal structure of the combustion synthesized source powder after thermal annealing. As a consequence, the annealed films exhibit both strong photoluminescence and a temperature-dependent lifetime that decreases from 2.9 ms at 298 K to 2.1 ms at 370 K. Ruby films were also deposited on multiple substrates. To ensure a continuous film with smooth surface morphology and strong photoluminescence, we use a sapphire substrate, which is thermal expansion coefficient and lattice matched to the film. These thin ruby films can potentially be used as remote temperature sensors for probing the local temperatures of micro and nanoscale structures.

  8. Laser microsampling method for determination of retained fission gas in irradiated nuclear fuels

    International Nuclear Information System (INIS)

    Graczyk, D.G.; Bandyopadhyay, G.; Gehl, S.M.; Hughes, J.P.; Goodspeed, H.T.

    1979-10-01

    A small ruby laser adapted to fire through a microscope is used to release fission gases from specific sites on a plane surface of an irradiated fuel specimen. Interaction of the focused laser pulse with the specimen surface results in a conical crater from which sampled material has been vaporized; the crater is surrounded by a heat-affected zone in which intergranular fracture and grain separation allow release of grain-boundary gases. Procedures for measuring the amount of krypton-85 released by laser heating and the volume of material from which the release occurred are presented. The data obtained may be used to obtain local krypton fission-gas concentrations and the intragranular/intergranular distribution

  9. RUBI -a Reference mUltiscale Boiling Investigation for the Fluid Science Laboratory

    Science.gov (United States)

    Schweizer, Nils; Stelzer, Marco; Schoele-Schulz, Olaf; Picker, Gerold; Ranebo, Hans; Dettmann, Jan; Minster, Olivier; Toth, Balazs; Winter, Josef; Tadrist, Lounes; Stephan, Peter; Grassi, Walter; di Marco, Paolo; Colin, Catherine; Piero Celata, Gian; Thome, John; Kabov, Oleg

    Boiling is a two-phase heat transfer process where large heat fluxes can be transferred with small driving temperature differences. The high performance of boiling makes the process very interesting for heat transfer applications and it is widely used in industry for example in power plants, refrigeration systems, and electronics cooling. Nevertheless, due to the large number of involved phenomena and their often highly dynamic nature a fundamental understanding and closed theoretical description is not yet accomplished. The design of systems incorporating the process is generally based on empirical correlations, which are commonly accompanied by large uncertainties and, thus, has to be verified by expensive test campaigns. Hence, strong efforts are currently made to develop applicable numerical tools for a reliable prediction of the boiling heat transfer performance and limits. In order to support and validate this development and, in particular as a precondition, to enhance the basic knowledge about boiling the comprehensive multi-scale experiment RUBI (Reference mUlti-scale Boiling Investigation) for the Fluid Science Laboratory on board the ISS is currently in preparation. The scientific objectives and requirements of RUBI have been defined by the members of the ESA topical team "Boiling and Multiphase Flow" and addresses fundamental aspects of boiling phenomena. The main objectives are the measurement of wall temperature and heat flux distribution underneath vapour bubbles with high spatial and tem-poral resolution by means of IR thermography accompanied by the synchronized high-speed observation of the bubble shapes. Furthermore, the fluid temperature in the vicinity and inside of the bubbles will be measured by a micro sensor array. Additional stimuli are the generation of an electric field above the heating surface and a shear flow created by a forced convection loop. The objective of these stimuli is to impose forces on the bubbles and investigate the

  10. RubyMotion iOS develoment essentials

    CERN Document Server

    Nalwaya, Abhishek

    2013-01-01

    This is a step-by-step book that builds on your knowledge by adding to an example app over the course of each chapter. Each topic uses example code that can be compiled and tested to show how things work practically instead of just telling you the theory. Complicated tasks are broken down into easy to follow steps with clear explanations of what each line of code is doing.Whether you are a novice to iOS development or looking for a simpler alternative to Objective-C; with RubyMotion iOS Development Essentials, you will become a pro at writing great iOS apps

  11. 77 FR 21805 - Notice of Intent To Collect Fees on Public Land in Mesa County, CO (Ruby-Horsethief Stretch of...

    Science.gov (United States)

    2012-04-11

    ... public: The Ruby-Horsethief Business Plan (posted in November 2011) and the Ruby-Horsethief Environmental... Plan outlines operational goals of the area and the purpose of the fee program. The EA, Decision Record... related to the fee and permit. Both the Business Plan and the EA provide management direction for public...

  12. Aplicação de ethephon e qualidade da uva 'Rubi' em Porto Feliz-SP Ethephon on 'Rubi' grapevine quality in Porto Feliz, SP

    Directory of Open Access Journals (Sweden)

    Alessandro Rodrigues

    2010-09-01

    Full Text Available A produção de uvas de mesa é uma importante atividade econômica no Estado de São Paulo. A região de Porto Feliz, em clima Cwa, apresenta grande número de agricultores familiares dedicados a esta atividade. Condições climáticas e manejo da cultura durante a fase de amadurecimento determinam a qualidade dos bagos, sendo o uso de fitorreguladores uma ferramenta útil para o ajustamento de atributos da qualidade. Avaliaram-se sete concentrações de ethephon, aplicadas por imersão dos cachos no início da mudança de coloração dos bagos, sobre a qualidade de uva 'Rubi', durante os ciclos de 2007 e de 2008, em propriedade comercial localizada em Porto Feliz-SP. Os atributos de qualidade avaliados foram a coloração de bagos, teor de sólidos solúveis totais e desbagoamento pós-colheita, sendo determinado também o índice de velocidade de desbagoamento. Os dados coletados foram submetidos à análise de variância e de regressão. Em 2007, observaram-se maiores coloração e teor de sólidos solúveis totais, associados às maiores temperaturas registradas no período entre o início de maturação e a colheita. O uso de ethephon, independentemente da concentração utilizada, promoveu coloração mais avermelhada dos bagos de 'Rubi' nas duas safras. Não houve efeito do uso do ethephon sobre o teor de sólidos solúveis totais. Não foi possível inferir sobre o efeito do etephon no desbagoamento em função do elevado coeficiente de variação. Estudos básicos para avaliar o efeito de fatores climáticos, nutricionais e de manejo do vinhedo são necessários no desenvolvimento de coloração dos bagos da cultivar 'Rubi' em clima tropical.Grapevine production for fresh market is an important economic activity in the State of Sao Paulo, Brazil. The region of Porto Feliz is located in Cwa climate and concentrates several small producers. Climatic conditions and cultural practices during fruit maturation determine berry quality, and

  13. A new handling tool for irradiated samples at the LENA plant

    International Nuclear Information System (INIS)

    Alloni, L.; Venturelli, A.

    1988-01-01

    The handling of neutron irradiated samples at the LENA plant has been so far carried out manually, thus exposing reactor and health physics operators and reactor users to radiation doses. It was then decided to develop an automatic system operated from the reactor console. The system was divided in two sections: one taking care of sample insertion and extraction and the other of the storage of irradiated samples. This paper describes the design and the installation of the storage section. It allows a fast removal of the irradiated samples from the reactor top and their storage in lead pits at the ground level. The extraction of irradiated samples comes out to be quite simplified and radiation doses to operators and users are strongly reduced. All work from design to construction has been carried out by the personnel of the electronic group of the LENA plant

  14. What's a Nice Hummingbird Like You Doing at an AGU Meeting Like This? (or, Operation RubyThroat Meets The GLOBE Program)

    Science.gov (United States)

    Hilton, B.

    2003-12-01

    "Operation RubyThroat: The Hummingbird Project" is an international cross-disciplinary initiative that uses Ruby-throated Hummingbirds (Archilochus colubris) as a hook to excite K-12 students (and adults) about science learning. In 2002, Operation RubyThroat affiliated with The GLOBE Program as the first GLOBE protocol that involves animal behavior. Through Operation RubyThroat, students make observations about hummingbird phenology, behavior, and ecology and correlate their data against traditional GLOBE observations of atmosphere, climate, land cover, soils, hydrology, and phenology. Although Ruby-throated Hummingbirds (RTHUs) breed throughout the eastern half of the United States and southern Canada and may be the most common and most widely distributed of all 338 hummingbird species, little is known about how abiotic environmental factors affect their migration, nesting activities, and everyday behavior. Operation RubyThroat participants in the U.S. and Canada log early arrival dates of RTHUs during spring migration, note their presence throughout the breeding season, and report the last date RTHUs are seen in autumn. Conversely, participants in Mexico and all seven Central American countries (the region in which RTHUs spend their non-breeding months) watch for early arrivals in fall and late departures in spring. Participants also attempt to estimate numbers of RTHUs in local populations by counting the number of visits hummingbirds make to feeders and/or flowers in a 45-minute time block. Optional activities include observations of RTHU nesting behaviors and determining RTHU preferences for various species of native and exotic nectar sources. Participating schools are encouraged to establish Schoolyard Hummingbird Habitats in which to make their observations, but data may be collected in backyards or at local parks, nature centers, botanical gardens, and other sites where RTHUs occur. Adults not affiliated with K-12 schools are invited to become certified in

  15. Mutation of Rubie, a novel long non-coding RNA located upstream of Bmp4, causes vestibular malformation in mice.

    Directory of Open Access Journals (Sweden)

    Kristina A Roberts

    Full Text Available The vestibular apparatus of the vertebrate inner ear uses three fluid-filled semicircular canals to sense angular acceleration of the head. Malformation of these canals disrupts the sense of balance and frequently causes circling behavior in mice. The Epistatic circler (Ecl is a complex mutant derived from wildtype SWR/J and C57L/J mice. Ecl circling has been shown to result from the epistatic interaction of an SWR-derived locus on chromosome 14 and a C57L-derived locus on chromosome 4, but the causative genes have not been previously identified.We developed a mouse chromosome substitution strain (CSS-14 that carries an SWR/J chromosome 14 on a C57BL/10J genetic background and, like Ecl, exhibits circling behavior due to lateral semicircular canal malformation. We utilized CSS-14 to identify the chromosome 14 Ecl gene by positional cloning. Our candidate interval is located upstream of bone morphogenetic protein 4 (Bmp4 and contains an inner ear-specific, long non-coding RNA that we have designated Rubie (RNA upstream of Bmp4 expressed in inner ear. Rubie is spliced and polyadenylated, and is expressed in developing semicircular canals. However, we discovered that the SWR/J allele of Rubie is disrupted by an intronic endogenous retrovirus that causes aberrant splicing and premature polyadenylation of the transcript. Rubie lies in the conserved gene desert upstream of Bmp4, within a region previously shown to be important for inner ear expression of Bmp4. We found that the expression patterns of Bmp4 and Rubie are nearly identical in developing inner ears.Based on these results and previous studies showing that Bmp4 is essential for proper vestibular development, we propose that Rubie is the gene mutated in Ecl mice, that it is involved in regulating inner ear expression of Bmp4, and that aberrant Bmp4 expression contributes to the Ecl phenotype.

  16. Effects of water treatment and sample granularity on radiation sensitivity and stability of EPR signals in X-ray irradiated bone samples

    International Nuclear Information System (INIS)

    Ciesielski, Bartlomiej; Krefft, Karolina; Penkowski, Michal; Kaminska, Joanna; Drogoszewska, Barbara

    2014-01-01

    The article describes effects of sample conditions during its irradiation and electron paramagnetic resonance (EPR) measurements on the background (BG) and dosimetric EPR signals in bone. Intensity of the BG signal increased up to two to three times after crushing of bone to sub-millimetre grains. Immersion of samples in water caused about 50 % drop in intensity of the BG component followed by its regrowth in 1-2 months. Irradiation of bone samples produced an axial dosimetric EPR signal (radiation-induced signal) attributed to hydroxyapatite component of bone. This signal was stable and was not affected by water. In samples irradiated in dry conditions, EPR signal similar to the native BG was also generated by radiation. In samples irradiated in wet conditions, this BG-like component was initially much smaller than in bone irradiated as dry, but increased in time, reaching similar levels as in dry-irradiated samples. It is concluded that accuracy of EPR dosimetry in bones can be improved, if calibration of the samples is done by their irradiations in wet conditions. (authors)

  17. [Agrobacterium rubi strains from blueberry plants are highly diverse].

    Science.gov (United States)

    Abrahamovich, Eliana; López, Ana C; Alippi, Adriana M

    2014-01-01

    The diversity of a collection of Agrobacterium rubi strains isolated from blueberries from different regions of Argentina was studied by conventional microbiological tests and molecular techniques. Results from biochemical and physiological reactions, as well as from rep-PCR and RFLP analysis of PCR-amplified 23S rDNA showed high phenotypic and genotypic intraspecific variation. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  18. Tube closure device, especially for sample irradiation

    International Nuclear Information System (INIS)

    Klahn, F.C.; Nolan, J.H.; Wills, C.

    1979-01-01

    Device for closing the outlet of a bore and temporarily locking components in this bore. Specifically, it concerns a device for closing a tube containing a set of samples for monitoring irradiation in a nuclear reactor [fr

  19. Inert medium (helium) irradiation testing of pressure tube samples

    International Nuclear Information System (INIS)

    Ancuta, M.; Radu, V.; Stefan, V.; Preda, M.

    2001-01-01

    Irradiation tests currently performed in C-5 capsule aim at obtaining data and information concerning behavior to irradiation of pressure tubes of CANDU type fuel channel, to evidence the factors limiting operation life span. A calculation code for analysis and prediction of pressure tube behavior should be based upon periodical inspection results, post irradiation examination of the removed from reactor pressure tubes as well as on the experimental results obtained with materials subjected to irradiation conditions identical with the operational ones. Mechanical behavior analysis should focus both complex thermal-mechanical type stresses and mechanical properties alteration under irradiation. The experimental results should be applied: - to evaluate the irradiation effects upon mechanical properties of Zr-2.5% Nb exposed to fluences up to 10 21 n·cm -2 ; - to gather data concerning the real stress / real deformation characteristic from which characteristic quantities can be deduced as, for instance, elasticity modulus, plasticity modulus, exponent of stress term in the Tsu-Berteles relation, to be used within the CANTUP simulation code describing pressure tube behavior, currently developed at INR Pitesti; - to develop prediction methods of pressure tube behavior and merging with in-service inspection procedure in order to forecast the life span and the proper timing for replacement before major failures occur. The samples irradiated in C-5 capsule were extracted from the ends of Zr-2.5% Nb pressure tubes resulting from Cernavoda NPP Unit 1. The samples for tensile tests were extracted on longitudinal and transversal directions of the pressure tube. The tests were carried out under following conditions: - test environment temperature, 260 - 280 deg.C; - testing medium, helium at 1 - 6 b pressure; - neutron flux (E n > 1 MeV), 1 - 2 · 10 13 ncm -2 s -1 ; - neutron fluence (E n > 1 MeV), 4 · 10 20 ncm -2 . The following characteristics were obtained from tensile

  20. Making waves the story of Ruby Payne-Scott : Australian pioneer radio astronomer

    CERN Document Server

    Goss, M

    2013-01-01

    This book is an abbreviated, partly re-written version of "Under the Radar - The First Woman in Radio Astronomy: Ruby Payne-Scott." It addresses a general readership interested in historical and sociological aspects of astronomy and presents the biography of Ruby Payne-Scott (1912 – 1981). As the first female radio astronomer (and one of the first people in the world to consider radio astronomy), she made classic contributions to solar radio physics. She also played a major role in the design of the Australian government's Council for Scientific and Industrial Research radars, which were in turn of vital importance in the Southwest Pacific Theatre in World War II. These radars were used by military personnel from Australia, the United States and New Zealand. From a sociological perspective, her career offers many examples of the perils of being a female academic in the first half of the 20th century. Written in an engaging style and complemented by many historical photographs, this book offers fascinating...

  1. Study of irradiation damage by fast neutrons in samples of Portland cement

    International Nuclear Information System (INIS)

    Lucki, G.; Rosa Junior, A.A.

    1984-01-01

    The effect of neutron irradiation in samples of Portland cement was evaluated, using the resonance frequency method and pulse velocity of ultra-sound techniques. The samples were divided in three groups: 1) monitoring samples; 2) samples submitted to gamma heating; 3) Irradiated samples. In the sample preparation, it was used the Portland Santa Rita CP 320 cement, and water-cement rate of 0.40 l/Kg. The irradiation was done in the research reactor IEA-R1, at IPEN - CNEN/SP, with an integrated flux of 7.2 x 10 18 n/cm 2 (E approx. 1 MeV). Some damage were detected, due to the neutron flux, and by the thermal effect of gamma heating. (E.G.) [pt

  2. Neutron-Irradiated Samples as Test Materials for MPEX

    International Nuclear Information System (INIS)

    Ellis, Ronald James; Rapp, Juergen

    2015-01-01

    Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by fast neutron irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. This paper presents assessments of the calculated induced radioactivity and resulting radiation dose rates of a variety of potential fusion reactor plasma-facing materials (such as tungsten). The scientific code packages MCNP and SCALE were used to simulate irradiation of the samples in HFIR including the generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. A challenge of the MPEX project is to minimize the radioactive inventory in the preparation of the samples and the sample dose rates for inclusion in the MPEX facility

  3. Stress measurements in a magnesium oxide single crystal under constant load using the R-line shifts in a ruby sphere on a Raman microscope

    International Nuclear Information System (INIS)

    Banini, G.K.

    2005-01-01

    Using a Renishaw Raman Microscope and a constructed mechanical apparatus, a novel method for determining the stress in the contact region between a ruby indenter and an MgO crystal under static contact lead is described. The experiment was performed under normal laboratory conditions at the Cavendish Laboratory, University of Cambridge, UK. Manual focusing using the white light on the microscope was made onto the ruby sphere and by replacing the light with a HeNe laser, luminescence frequency in the R-lines of chromium ions at the relaxed (unstressed) positions could be determined. The MgO crystal was then quasi-statically loaded by the ruby sphere, while in the mechanical loading apparatus, and placed on the Renishaw. Manual focusing onto the ruby sphere was made through the MgO and the shift in R-lines from the relaxed positions determined. Literature values of stress coefficients in ruby were used to convert the shifts determined in the R-lines into hydrostatic and non-hydrostatic stresses at precise intervals across the contact region. It was revealed that large stresses hydrostatic occur in the contact region during quasi-static loading and these can be quantified for transparent solids (au)

  4. An automatic device for sample insertion and extraction to/from reactor irradiation facilities

    International Nuclear Information System (INIS)

    Alloni, L.; Venturelli, A.; Meloni, S.

    1990-01-01

    At the previous European Triga Users Conference in Vienna,a paper was given describing a new handling tool for irradiated samples at the L.E.N.A plant. This tool was the first part of an automatic device for the management of samples to be irradiated in the TRIGA MARK ii reactor and successively extracted and stored. So far sample insertion and extraction to/from irradiation facilities available on reactor top (central thimble,rotatory specimen rack and channel f),has been carried out manually by reactor and health-physics operators using the ''traditional'' fishing pole provided by General Atomic, thus exposing reactor personnel to ''unjustified'' radiation doses. The present paper describes the design and the operation of a new device, a ''robot''type machine,which, remotely operated, takes care of sample insertion into the different irradiation facilities,sample extraction after irradiation and connection to the storage pits already described. The extraction of irradiated sample does not require the presence of reactor personnel on the reactor top and,therefore,radiation doses are strongly reduced. All work from design to construction has been carried out by the personnel of the electronic group of the L.E.N.A plant. (orig.)

  5. Development of real-time radiation exposure dosimetry system using synthetic ruby for interventional radiology

    International Nuclear Information System (INIS)

    Hosokai, Yoshiyuki; Win, Thet Pe; Muroi, Kenzo; Matsumoto, Kenki; Takahashi, Kaito; Usui, Akihito; Saito, Haruo; Kozakai, Masataka

    2017-01-01

    Interventional radiology (IVR) tends to involve long procedures, consequently delivering high radiation doses to the patient. Radiation-induced injuries that occur because of the effect of the high radiation doses are a considerable problem for those performing IVR. For example, skin injuries can include skin erythema if the skin is exposed to radiation doses beyond the threshold level of 2 Gy. One of the reasons for this type of injury is that the local skin dose cannot be monitored in real time. Although there are systems employed to measure the exposure dose, some do not work in real time (such as thermoluminescence dosimeters and fluorescent glass dosimeters), while certain real-time measurement systems that enter the field of view (such as patient skin dosimeters and dosimeters using a nontoxic phosphor) interfere with IVR. However, synthetic ruby has been shown to emit light in response to radiation. The luminous wavelength is 693 nm. It is possible to monitor the radiation dose by detecting the emitted light. However, small synthetic rubies emit a tiny amount of light that is difficult to detect using common systems such as photodiodes. A large enough synthetic ruby to increase the quantity of emitted light would however enter the field of view and interfere with the IVR procedure. Additionally, although a photodiode system could reduce the system size, the data is susceptible to effects from the X-rays and outside temperature. Therefore, use of a sensitive photon counting system as used in nuclear medicine could potentially have a beneficial effect in detecting the weak light signal. A real-time radiation exposure dosimetry system for use in IVR should be sufficiently sensitive, not interfere with the IVR procedure, and ideally have the possibility of development into a system that can provide simultaneous multipoint measurements. This article discusses the development of a realtime radiation exposure dosimetry system for use in IVR that employs a small

  6. Growth of ruby crystals by the heat exchanger method, phase 1: NSF small business innovation research

    Science.gov (United States)

    Schmid, F.; Khattak, C. P.

    1980-03-01

    Conditions for the growth of large, uniformly doped laser crystals by the heat exchanger method are explored. Determination of the melt point, selection of crucible material and establishment of furnace operating parameters are discussed. The melt point of ruby was found to be 2040 plus or minus 10 C. Molybdenum crucibles can be used to contain ruby in vacuum as well as under argon atmospheres at desired superheat temperatures over extended periods required for crystal growth. Thermodynamic analysis was conducted and vapor pressures of volatile species calculated. Experimentally, volatilization of chromium oxides was suppressed by using welded covers on crucibles and operating under an argon pressure in the furnace.

  7. Irradiation test of mirror samples for the LHCb SciFi tracker

    CERN Document Server

    Joram, Christian; Gavardi, Laura; Ravotti, Federico; Schneider, Thomas

    2016-01-01

    The optical mirrors at the inner ends of the SciFi fibre modules in the upgraded LHCb detector will be exposed to an ionising dose reaching 35 kGy for an integrated luminosity of 50 /fb. This note describes a campaign at the cyclotron at KIT where 7 different samples were irradiated with 23 MeV protons. The samples consisted of plastic scintillator tiles, on which two different mirror foils – aluminised mylar and 3M ESR - were attached with two different glues – Epotek H301-2FL and Dow Corning RTV 3145. The transmission and/or reflectivity of the samples were measured before and after irradiation. The measurements reveal the combination of 3M ESR foil and Epotek H301-2FL to give the highest reflectivity, before and also after irradiation. In all cases, the irradiation leads only to a small, i.e. less than 10%, degradation of the transmission or reflectivity. From a radiation hardness point of view, all investigated mirror samples qualify for use in the SciFi detector.

  8. Oxidative stability examination of irradiated swine for samples

    International Nuclear Information System (INIS)

    Formanek, Z.

    1995-01-01

    DSC (Differential Scanning Calorimetry), OBM (Oxygen Bomb Method) methods and POV (Peroxide Value) determination was applied to determine the oxidative stability of lard samples irradiated by a Co 60 gamma source at the dose of 0; 0.75; 2.5kGy. Both of the methods seem to be suitable to determine oxidative stability of fats, because in every case lowering oxidative stability was received with increasing irradiation dose. (R.P.). 8 refs., 7 figs., 1 tab

  9. Remotised sliver sample removal from irradiated pressure tube

    Energy Technology Data Exchange (ETDEWEB)

    Rupani, B B; Sharma, B S.V.G.; Shyam, T V; Sinha, R K [Bhabha Atomic Research Centre, Bombay (India). Reactor Engineering Div.

    1994-12-31

    The life of irradiated pressure tubes of Pressurised Heavy Water Reactor (PHWR) can be assessed by analysing hydrogen content in sliver samples of pressure tube material. The sample can be obtained in the form of small slivers by scraping at any specified locations within the bore of the pressure tube of operating reactor. A tool namely Hydride Scraping Tool (HST) has been developed to obtain very thin slivers of hydride bearing samples from irradiated pressure tube. In order to save man-rem consumption during scraping operation, a feeding mechanism has also been designed and developed for axial positioning of scraping tool in the channel remotely. This paper covers general details about constructional features of the scraping tool, feeding mechanism and their control system. It also highlights the operational salient features and capabilities of the system. Possible applications of the feeding mechanism in other fields are also indicated. (author). 4 figs.

  10. Remotised sliver sample removal from irradiated pressure tube

    International Nuclear Information System (INIS)

    Rupani, B.B.; Sharma, B.S.V.G.; Shyam, T.V.; Sinha, R.K.

    1994-01-01

    The life of irradiated pressure tubes of Pressurised Heavy Water Reactor (PHWR) can be assessed by analysing hydrogen content in sliver samples of pressure tube material. The sample can be obtained in the form of small slivers by scraping at any specified locations within the bore of the pressure tube of operating reactor. A tool namely Hydride Scraping Tool (HST) has been developed to obtain very thin slivers of hydride bearing samples from irradiated pressure tube. In order to save man-rem consumption during scraping operation, a feeding mechanism has also been designed and developed for axial positioning of scraping tool in the channel remotely. This paper covers general details about constructional features of the scraping tool, feeding mechanism and their control system. It also highlights the operational salient features and capabilities of the system. Possible applications of the feeding mechanism in other fields are also indicated. (author). 4 figs

  11. Effect of interaction between irradiation-induced defects and intrinsic defects in the pinning improvement of neutron irradiated YBaCuO sample

    International Nuclear Information System (INIS)

    Topal, Ugur; Sozeri, Huseyin; Yavuz, Hasbi

    2004-01-01

    Interaction between the intrinsic (native) defects and the irradiation-induced defects created by neutron irradiation was examined for the YBCO sample. For this purpose, non-superconducting Y-211 phase was included to the Y-123 samples at different contents as a source of large pinning center. The critical current density enhancement with the irradiation for these samples were analysed and then the role of defects on pinning improvement was discussed

  12. Effect of interaction between irradiation-induced defects and intrinsic defects in the pinning improvement of neutron irradiated YBaCuO sample

    Energy Technology Data Exchange (ETDEWEB)

    Topal, Ugur; Sozeri, Huseyin; Yavuz, Hasbi

    2004-08-01

    Interaction between the intrinsic (native) defects and the irradiation-induced defects created by neutron irradiation was examined for the YBCO sample. For this purpose, non-superconducting Y-211 phase was included to the Y-123 samples at different contents as a source of large pinning center. The critical current density enhancement with the irradiation for these samples were analysed and then the role of defects on pinning improvement was discussed.

  13. Measurements of the parametric decay of CO2 laser radiation into plasma waves at quarter critical density using ruby laser Thomson scattering

    International Nuclear Information System (INIS)

    Schuss, J.J.; Chu, T.K.; Johnson, L.C.

    1977-11-01

    We report the results of small-angle ruby laser Thomson scattering measurements of the parametric excitation of plasma waves by CO 2 laser radiation at quarter-critical density in a laser-heated gas target plasma. From supplementary data obtained from interferometry and large-angle ruby laser scattering we infer that the threshold conditions for a convective decay are satisfied

  14. Database of Samples Irradiated at Reactor TRIGA PUSPATI (RTP)

    International Nuclear Information System (INIS)

    Muhd Husamuddin Abdul Khalil; Mohd Amin Sharifuldin Salleh; Julia Abdul Karim

    2011-01-01

    Evaluation has been made to data of irradiated samples for the type of sample requested for activation at RTP. Sample types are grouped with percentage of total throughputs to rule out the weight percent of every respective group. The database consists of radionuclide inventory of short and long half-life and high activity radionuclides such as Br and Au have been identified and that database has been constructed using a user-friendly Microsoft Access. Through this, trend of gamma exposure will easily be evaluated at experimental facilities and could ensure radiological effect towards safety and health is limited per Radiation Protection (Basic Safety Standard) Regulation 1988. This database places an important parameter to improve management system in acquiring information of the samples irradiated at RTP and will enhance the safety assurance and reliability of the experimental design basis. (author)

  15. Surface and bulk 3D analysis of natural and processed ruby using electron probe micro analyzer and X-ray micro CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, Rakesh K., E-mail: rakesh.materialscience@gmail.com; Singh, Saroj K.; Mishra, B.K.

    2016-08-15

    Highlights: • Firm linking between two advance techniques: Micro-CT and EPMA for mineral analysis. • Attempt to identify and differentiate the treated gem stone from natural counterpart. • 3D structural and surface elemental analysis of the natural gem stone. - Abstract: The change in surface compositional and bulk structural characteristics of the natural ruby stone, before and after heat treatment with lead oxide has been analyzed using two advance characterization techniques like: X-ray micro CT scan (μ-CT) and electron probe micro analyzer (EPMA). The analytical correlation between these two techniques in identification as well as in depth study of the ores and minerals before and after processing has been presented. Also, we describe the aesthetic enhancement of a low quality defective ruby stone by lead oxide filling and the sequential analysis of this ruby stone before and after treatment using these two advanced techniques to identify and to confirm the change in its aesthetic value. The cracks healing and pores filling by the metal oxide on the surface of the ruby have been analyzed using μ-CT and EPMA. Moreover, in this work we describe the advance characterization of the repaired gem stones especially ruby stones. This work will light up the path for in-depth understanding of diffusion mechanism and abstract information of impurity particles inside the minerals. Based on these observations, EPMA and micro CT are shown to be powerful tools for the identification as well as research in gem stones.

  16. Infinite projected entangled-pair state algorithm for ruby and triangle-honeycomb lattices

    Science.gov (United States)

    Jahromi, Saeed S.; Orús, Román; Kargarian, Mehdi; Langari, Abdollah

    2018-03-01

    The infinite projected entangled-pair state (iPEPS) algorithm is one of the most efficient techniques for studying the ground-state properties of two-dimensional quantum lattice Hamiltonians in the thermodynamic limit. Here, we show how the algorithm can be adapted to explore nearest-neighbor local Hamiltonians on the ruby and triangle-honeycomb lattices, using the corner transfer matrix (CTM) renormalization group for 2D tensor network contraction. Additionally, we show how the CTM method can be used to calculate the ground-state fidelity per lattice site and the boundary density operator and entanglement entropy (EE) on an infinite cylinder. As a benchmark, we apply the iPEPS method to the ruby model with anisotropic interactions and explore the ground-state properties of the system. We further extract the phase diagram of the model in different regimes of the couplings by measuring two-point correlators, ground-state fidelity, and EE on an infinite cylinder. Our phase diagram is in agreement with previous studies of the model by exact diagonalization.

  17. Whole genome sequences of the raspberry and strawberry pathogens Phytophthora rubi and P. fragariae

    Science.gov (United States)

    Phytophthora rubi and P. fragariae are two closely related oomycete plant pathogens that exhibit strong morphological and physiological similarities, but are specialized to infect different hosts of economic importance, namely raspberry and strawberry. Here, we report the draft genome sequences of t...

  18. Container for gaseous samples for irradiation at accelerators

    International Nuclear Information System (INIS)

    Kupsch, H.; Riemenschneider, J.; Leonhardt, J.

    1985-01-01

    The invention concerns a container for gaseous samples for the irradiation at accelerators especially to generate short-lived radioisotopes. The container is also suitable for storage and transport of the target gas and can be multiply reused

  19. 16 CFR 23.23 - Misuse of the words “ruby,” “sapphire,” “emerald,” “topaz,” “stone,” “birthstone,” “gemstone,” etc.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Misuse of the words âruby,â âsapphire,â... PEWTER INDUSTRIES § 23.23 Misuse of the words “ruby,” “sapphire,” “emerald,” “topaz,” “stone,” “birthstone,” “gemstone,” etc. (a) It is unfair or deceptive to use the unqualified words “ruby,” “sapphire...

  20. Effect of gamma irradiation on the storage and vitamin C concentration of allium cepa onion samples

    International Nuclear Information System (INIS)

    Saleh, M. A. M.

    2013-07-01

    This study was done to investigate the effect of gamma irradiation on storage, germination and vitamin C concentration of local onion (Allium cepa). 5 onion samples were irradiated with 5 different radiation doses (0.1, 0.2, 0.3, 0.4, and 0.5 k Gray) using cobalt-60 irradiator (Nor din) compared to non irradiated samples as controls. The irradiated and control onions were stored at room temperature for three months. The results of this study showed that the non irradiated samples were either deteriorated or grown while all the irradiated samples were not. Regarding the concentration of vitamin C it was clear that it decreased with the dose increase from 30.53 to 14.44 mg/100 g. This study concluded that the irradiation is very effective in prevention of spoilage, elongation of germination period and decrease of vitamin C concentration.(Author)

  1. Fractional CO2 laser is as effective as Q-switched ruby laser for the initial treatment of a traumatic tattoo.

    Science.gov (United States)

    Seitz, Anna-Theresa; Grunewald, Sonja; Wagner, Justinus A; Simon, Jan C; Paasch, Uwe

    2014-12-01

    Q-switched laser treatments are considered the standard method for removing both regular and traumatic tattoos. Recently, the removal of tattoo ink using ablative fractional lasers has been reported. Ablative fractional CO2 laser and q-switched ruby laser treatments were used in a split-face mode to compare the safety and efficacy of the two types of laser in removing a traumatic tattoo caused by the explosion of a firework. A male patient suffering from a traumatic tattoo due to explosive deposits in his entire face was subjected to therapy. A series of eleven treatments were performed. The right side of the face was always treated using an ablative fractional CO2 laser, whereas the left side was treated only using a q-switched ruby laser. After a series of eleven treatments, the patient demonstrated a significant lightening on both sides of his traumatic tattoo, with no clinical difference. After the first six treatments, the patient displayed greater lightening on the right side of his face, whereas after another five treatments, the left side of the patient's face appeared lighter. No side effects were reported. In the initial stage of removing the traumatic tattoo, the ablative fractional laser treatment appeared to be as effective as the standard ruby laser therapy. However, from the 6th treatment onward, the ruby laser therapy was more effective. Although ablative fractional CO2 lasers have the potential to remove traumatic tattoos, they remain a second-line treatment option.

  2. Energetic improvement with micro turbines of biogas generated in Rubis WWTP; Aprovechamiento energetico con microturbinas del biogas generado en la EDAR de Rubi

    Energy Technology Data Exchange (ETDEWEB)

    Moragas, L.; Robuste, J.; Vicente, M.; Pozo, A.; Blasco, M.

    2009-07-01

    The WWTP of Rubi (Barcelona, Spain) treats 22.950 m{sup 3}/day by activated sludge system, with mesophilic anaerobic digestion of primary and secondary sludges with a capacity of 3.500 m{sup 3}. Generated biogas is applied by means of indirect heating to digesters at 37 degree centigrade. To improve the energetic performance 2 micro turbines of 65 kW each were installed, with a 29% of unitary electric performance. After 5 months a third turbine was installed to generate more energy in peak hours. this solutions has shown to be very flexible, with reasonable technology and costs. (Author)

  3. 75 FR 66779 - Ruby Lake National Wildlife Refuge, Elko and White Pine Counties, NV; Comprehensive Conservation...

    Science.gov (United States)

    2010-10-29

    ... emanating from the base of the Ruby Mountains provide life-sustaining water to the 39,926-acre refuge. The marsh is surrounded by 22,926 acres of meadows, grasslands, alkali playa, and shrub-steppe uplands...

  4. Change of microflora of two starch samples by gamma irradiation

    International Nuclear Information System (INIS)

    Fretton, R.; Fretton, J.; Delattre, J.M.

    1975-01-01

    Starch is the basic component of a larger number of manufactured foods. The disinfection of such a powder by 60 Co is studied here. Gamma irradiation of two starch samples with different degrees of contamination allows the assumption that, in most cases, good radio-pasteurization can be achieved with 300 krad. The radio-pasteurization doses (varying from 300 to 600 krad) are a function of the initial contamination. Irradiation effects are spectacular with moulds. Activation of spores of some Clostridium species leads us to recommend an irradiation level higher than 200 krad. The most resistant organisms to gamma irradiation are the aerobic and anaerobic sporulated bacteria. The thermophilic forms are the most important. Spores of Bacillus, chiefly Bacillus licheniformis and Bacillus brevis, are the most frequent bacteria. Storage of irradiated starch at room temperature has little effect upon the number of revivable survivors. (orig.) [de

  5. Analysis of volatile organic compounds and sensory characteristics of pork loin samples irradiated to high doses

    International Nuclear Information System (INIS)

    Hou Zhengchi; Sun Dakuan; Qin Zongying; Jin Jiang; Zhu Liandi; Yao Side; Sheng Kanglong

    2005-01-01

    Fresh pork loin samples, protein enzyme inactivated at (72 ± 3) degree C and vacuum packaged, were irradiated to up to 45 kGy at -20 degree C by 60 Co γ-rays. The irradiated samples were examined by various kinds of method to study high dose irradiation effects of sensory changes (meat color and off-odor), transverse shearing strength, weight loss in steam cooking, volatile organic compounds, and lipid oxidation. The results showed that the high dose irradiation produced no serious effects to the pork loin samples, and volunteer responses showed fine acceptability to the irradiated meat. (authors)

  6. Device for taking gaseous samples from irradiated fuel elements

    International Nuclear Information System (INIS)

    Lengacker, B.

    1983-01-01

    The described device allows to take gaseous samples from irradiated fuel elements. It is connected with a gas analyzer and a pressure gage, so that in opening the fuel can the internal pressure can be determined

  7. KSb(OH) samples previously treated with Co y - rays irradiated with neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Facetti, J F [Asuncion Nacional Univ. (Paraguay). Inst. de Ciencias

    1969-01-01

    When Ksb (OH) samples previously treated with Co y - rays or crushed are irradiated with neutrons, the yield of Sb and the annealing mechanism are apparently modified by the pretreatment. In addition it is shown that metastable species of Sb are formed under irradiation.

  8. Effect of gamma irradiation on storability and chemical properties of different depth samples of luncheon

    International Nuclear Information System (INIS)

    Al-Bachir, M.; Farah, S.

    2000-03-01

    To investigate the effect of gamma irradiation on shelf-life of luncheon, meat packs were exposed to doses of 0, 1, 2 and 3 kGy in a 60 Co package irradiator, and the irradiated and unirradiated samples were stored at refrigeration temperature (1-3 centigrade). Microbial population and chemical changes were evaluated through storage periods (2, 4, 6 weeks) on the surface and depth in the of meat packs. The results indicated that gamma irradiation reduced the counts of microorganisms inside the samples more than the surfaces. Also the shelf-life of luncheon meat increased from two weeks for the control to 5 weeks for irradiated samples (2 and 3 kGy). Total acidity, lipid oxidation and the volatile basic nitrogen (VBN) increased during the first stage of storage up to 2 weeks of irradiation, furthermore these values were significantly higher (P> 0.05) on the surface than inside the meat packs. (author)

  9. Coexistence of both gyroid chiralities in individual butterfly wing scales of Callophrys rubi

    OpenAIRE

    Winter, Benjamin; Butz, Benjamin; Dieker, Christel; Schröder-Turk, Gerd E.; Mecke, Klaus; Spiecker, Erdmann

    2015-01-01

    Arthropod biophotonic nanostructures provide a plethora of complex geometries. Although the variety of geometric forms observed reflects those found in amphiphilic self-assembly, the biological formation principles are more complex. This paper addresses the chiral single gyroid in the Green Hairstreak butterfly Callophrys rubi, robustly showing that the formation process produces both the left- and right-handed enantiomers but with distinctly different likelihood. An interpretation excludes t...

  10. Influence of audiovisuals and food samples on consumer acceptance of food irradiation

    International Nuclear Information System (INIS)

    Pohlman, A.J.; Wood, O.B.; Mason, A.C.

    1994-01-01

    The effects of audiovisual presentation on consumers' knowledge and attitudes toward food irradiation were demonstrated. Food irradiation is a method of food preservation that can destroy the microorganisms responsible for many foodborne illnesses and food spoilage. However, the food industry has been slow to adopt this method because it is unsure of consumer acceptance. One hundred and seventy-nine consumers were given a slide-tape presentation on food irradiation. Test subjects were also presented with a sample of irradiated strawberries. It was found that participants knew more about and were more positive toward food irradiation following the educational program. These findings demonstrate the value of educational materials in influencing the food preferences of consumers

  11. Uranium hydrogeochemical and stream-sediment reconnaissance of the Ruby NTMS quadrangle, Alaska

    International Nuclear Information System (INIS)

    Hardy, L.C.; D'Andrea, R.F. Jr.; Zinkl, R.J.

    1982-07-01

    This report presents results of a Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Ruby NTMS quadrangle, Alaska. In addition to this abbreviated data release, more complete data are available to the public in machine-readable form. These machine-readable data, as well as quarterly or semiannual program progress reports containing further information on the HSSR program in general, or on the Los Alamos National Laboratory (LANL) portion of the program in particular, are available from DOE's Technical Library at its Grand Junction Area Office. Presented in this data release are location data, field analyses, and laboratory analyses of several different sample media. For the sake of brevity, many field site observations have not been included in this volume; these data are, however, available on the magnetic tape. Appendices A and B describe the sample media and summarize the analytical results for each medium. The data have been subdivided by one of the Los Alamos National Laboratory sorting programs of Zinkl and others (1981a) into groups of stream-sediment and lake-sediment samples. For each group which contains a sufficient number of observations, statistical tables, tables of raw data, and 1:1,000,000 scale maps of pertinent elements have been included in this report. Also included are maps showing results of multivariate statistical analyses. Information on the field and analytical procedures used by the Los Alamos National Laboratory during sample collection and analysis may be found in any HSSR data release prepared by the Laboratory and will not be included in this report

  12. Laboratory model for the study and treatment of traumatic tattoos with the Q-switched ruby laser

    Science.gov (United States)

    Silverman, Richard T.; Lach, Elliot

    1994-09-01

    The outcome of laser tattoo removal is dependent on the type of laser and characteristics of the tattoo. A rabbit model was developed to study the Q-switched ruby laser in the treatment of traumatic tattooing. On the backs of white New Zealand rabbits, three 3 cm patches were dermabraded and dressed with carbon black and antibiotic ointment. After a healing period of eight weeks, pre-treatment biopsies were obtained, and the rabbits were treated with the Q- switched ruby laser at various fluence settings with a pulse width of 34 nsec. At set intervals, further biopsies were obtained and studied with light and electron microscopic analysis, and photodocumentation was performed. Grossly, clearance of the tattooed areas was noted in the laser treated specimens. More effective clearance was observed with higher fluence treatment. No infections occurred, and hair regrowth was noted in all cases, though the rate seemed to be altered by laser treatment.

  13. Use of SCGE method for detection of DNA comet in irradiated samples of poultry and shrimp

    International Nuclear Information System (INIS)

    Rajaei, R.; Hosseini, S.L.

    2005-01-01

    DNA in food may sustain damage by gamma irradiation.This damage can be detected by a sensitive technique, called single cell gel electrophoresis. This is a simple and low-cost technique for rapid screening of the cells of irradiated foodstuffs. For this purpose, poultry and shrimp samples were irradiated by the 60 Co gamma radiation. The radiation doses for poultry were 2,5 and 7 kGy and for shrimp were 3 and 7kGy, respectively. The irradiation samples were compared with those of unirradiated types (control). In addition, the effects of shelf-life and temperature were considered on the poultry samples only. We have found that this technique is easily applicable for identification of irradiated from unirradiated samples and it is found to be irrespective of the applied dose. It is worth mentioning that any DNA change arising from any source, for example temperature fluctuation, may be detected by the single cell gel electrophoresis technique

  14. Dose response of artificial irradiation of fluvial sediment sample for ESR dating

    International Nuclear Information System (INIS)

    Liu Chunru; Yin Gongming; Gao Lu; Li Jianping; Han Fei; Lin Min

    2011-01-01

    ESR dating samples need be irradiated to obtain dose response curve and the equivalent dose. The artificial dose rate is about 1 x 10 -1 -1 x 10 2 Gy/min, whereas the natural dose rate is about 3 Gy/ka. Therefore, one must be sure whether the much higher artificial dose rate is suitable for the ESR dating study. In this paper, we use different artificial dose rate to irradiate the same fluvial sample and measure the quartz Al centre ESR signal under the same conditions. The dose response curves are compared, in an attempt to gain a preliminary knowledge on that problem and build a good foundation for our ESR dating studies on fluvial samples. (authors)

  15. Photodissociation of H2+ by a ruby laser with ion energy analysis of ejected H+

    International Nuclear Information System (INIS)

    Ozenne, J.B.; Pham, D.; Tadjeddine, M.; Durup, J.

    1974-01-01

    The kinetic energy released in the photodissociation of H 2 + by a ruby laser beam has been measured. The spectrum of the dissociation kinetic energy of H + +H shows several vibrational levels, and after deconvolution due to the energetic and angular resolution of the apparatus, gives a population of those vibrational levels, close to theoretical population [fr

  16. Polycrystal silicon recovery by means of a shaped laser pulse train

    International Nuclear Information System (INIS)

    Vitali, G.; Bertolotti, M.; Foti, G.

    1978-01-01

    A structure change from a polycrystal to single-crystal layer in ion-implanted Si samples has been obtained by single-pulse ruby-laser irradiation with a power density threshold of about 70 MW cm -2 (pulse length 50 nsec). Under these conditions surface mechanical damage is produced. A laser pulse train shaping technique was adopted to reduce the residual disorder in the layer after laser irradiation and to prevent mechanical damage

  17. Reflectivity of the gyroid biophotonic crystals in the ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi

    NARCIS (Netherlands)

    Michielsen, K.; De Raedt, H.; Stavenga, D. G.

    2010-01-01

    We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the

  18. Exogenous gibberellins inhibit coffee (Coffea arabica cv. Rubi) seed germination and cause cell death in the embryo

    NARCIS (Netherlands)

    Silva, Da E.A.A.; Toorop, P.E.; Nijsse, J.; Bewley, J.D.; Hilhorst, H.W.M.

    2005-01-01

    The mechanism of inhibition of coffee (Coffea arabica cv. Rubi) seed germination by exogenous gibberellins (GAs) and the requirement of germination for endogenous GA were studied. Exogenous GA4+7 inhibited coffee seed germination. The response to GA4+7 showed two sensitivity thresholds: a lower one

  19. Experimental fuel channel for samples irradiation at the RB reactor

    International Nuclear Information System (INIS)

    Pesic, M.; Markovic, H.; Sokcic-Kostic, M.; Miric, I.; Prokic, M.; Strugar, P.

    1984-12-01

    An 80% enriched UO 2 fuel channel at the RB nuclear reactor in the 'Boris Kidric' Institute of Nuclear Sciences is modified for samples irradiation by fast neutrons. Maximum sample diameter is 25 mm and length up to 1000 mm. Characteristics of neutron and gamma radiation fields of this new experimental channel are investigated. In the centre of the channel, the main contribution to the total neutron absorbed dose, i.e. 0.29 Gy/Wh of reactor operation, is due to the fast neutron spectrum component. Only 0.05 Gy and 0.07 Gy in the total neutron absorbed dose are due to intermediate and thermal neutrons, respectively. At the same time the gamma absorbed dose is 0.35 Gy. The developed experimental fuel channel, EFC, has wide possibilities for utilization, from fast neutron spectrum studies, electronic component irradiations, dosemeters testing, up to cross-section measurements. (author)

  20. Irradiations under magnetic field. Measurement of resistivity sample irradiations between 100 and 500 deg C in a swimming-pool reactor

    International Nuclear Information System (INIS)

    Pauleve, J.; Marchand, A.; Blaise, A.

    1964-01-01

    An oven is described which enables the irradiation of small samples in the maximum neutron flux of a swimming-pool reactor of 15 MW (Siloe), at temperatures of between 100 and 500 deg.C defined to ± 0,5 deg.C, The oven is very simple from the technological point of view, and has a diameter of only 27 mm, This permits resistivity measurements to be carried out under irradiation in the reactor, or as another example, it enables irradiations in a magnetic field of 5000 oersteds, created by an immersed solenoid. (authors) [fr

  1. Experimental investigation on variation of physical properties of coal samples subjected to microwave irradiation

    Science.gov (United States)

    Hu, Guozhong; Yang, Nan; Xu, Guang; Xu, Jialin

    2018-03-01

    The gas drainage rate of low-permeability coal seam is generally less than satisfactory. This leads to the gas disaster of coal mine, and largely restricts the extraction of coalbed methane (CBM), and increases the emission of greenhouse gases in the mining area. Consequently, enhancing the gas drainage rate is an urgent challenge. To solve this problem, a new approach of using microwave irradiation (MWR) as a non-contact physical field excitation method to enhance gas drainage has been attempted. In order to evaluate the feasibility of this method, the methane adsorption, diffusion and penetrability of coal subjected to MWR were experimentally investigated. The variation of methane adsorbed amount, methane diffusion speed and absorption loop for the coal sample before and after MWR were obtained. The findings show that the MWR can change the adsorption property and reduce the methane adsorption capacity of coal. Moreover, the methane diffusion characteristic curves for both the irradiated coal samples and theoriginal coal samples present the same trend. The irradiated coal samples have better methane diffusion ability than the original ones. As the adsorbed methane decreases, the methane diffusion speed increases or remain the same for the sample subjected to MWR. Furthermore, compared to the original coal samples, the area of the absorption loop for irradiated samples increases, especially for the micro-pore and medium-pore stage. This leads to the increase of open pores in the coal, thus improving the gas penetrability of coal. This study provides supports for positive MWR effects on changing the methane adsorption and improving the methane diffusion and the gas penetrability properties of coal samples.

  2. The computer system for the express-analysis of the irradiation samples

    International Nuclear Information System (INIS)

    Vzorov, I.K.; Kalmykov, A.V.; Korenev, S.A.; Minashkin, V.F.; Sikolenko, V.V.

    1999-01-01

    The computer system for the express-analysis (SEA) of the irradiation samples is described. The system is working together with the pulse high current electrons and ions source. It allows us to correct irradiation regime in real time. The SEA system automatically measures volt-ampere and volt-farad characteristics, sample resistance by 'four-probe' method, sample capacitor parameters. Its parameters are: in the volt-ampere measuring regime - U max = 200 V, minimal voltage step U sh =0.05 V, voltage accuracy 0.25%; in the capacity measuring regime - capacity measurement diapason 0 - 1600 pF, working frequencies diapason 1 -150 kHz, capacity accuracy 0.5%, voltage shifting diapason 1 - 200 V, minimal step of voltage shifting U sh 0.05 V. The SEA management is performed by IBM/AT computer. The control and measuring apparatus was realized in CAMAC standard. The programmed set consists of the first display procedures, control, treatment and information exit. (author)

  3. Production of gold and ruby-red lustres in Gubbio (Umbria, Italy) during the Renaissance period

    Science.gov (United States)

    Padeletti, G.; Fermo, P.

    The aim of this work is to gain a further insight into the knowledge of the production process of lustre-decorated ancient majolicas. Lustre is a sophisticated technique employed in the decoration of majolicas as used in central Italy during the Renaissance period. It consists of a beautiful iridescent gold or ruby-red thin metallic film, containing silver, copper and other substances and obtained in a reducing atmosphere on a previously glazed ceramic. Nowadays, it is not possible to replicate the outstanding results obtained by the ancient ceramicists, since the original recipes were lost. It is quite interesting to study lustre-production technology by means of analytical techniques now employed for advanced research on materials (XRD, ETAAS, ICP-OES, TEM-EDX-SAED and UV-Vis). In this work, we have focussed our attention on ceramic fragments decorated with both gold and ruby-red lustres, which were difficult to obtain due to complex reduction conditions required and which were a prerogative of Gubbio production. The two lustre colours differ in their chemical composition as well in their nanostructure. The presence of bismuth was disclosed and it was ascertained to be a distinctive feature of the Italian production.

  4. A transgressão do fantastico em Murilo Rubião

    OpenAIRE

    Fabio Dobashi Furuzato

    2002-01-01

    Resumo: Este trabalho é dividido em três partes. Na primeira, investigamos o percurso da obra do contista mineiro Murilo Eugênio Rubião (1916-1991), juntamente com a sua recepção crítica. Na segunda, partindo da afirmação de que Murilo seja o precursor do fantástico moderno em nossa prosa de ficção, realizamos um estudo teórico sobre este gênero literário. Na terceira parte, buscamos descrever todos os contos do autor, em função de um determinado conceito de fantástico. Por fim, levantamos um...

  5. Scientific communications: Re-Os sulfide (bornite, chalcopyrite, and pyrite) systematics of the carbonate-hosted copper deposits at ruby creek, southern brooks range, Alaska

    Science.gov (United States)

    Selby, D.; Kelley, K.D.; Hitzman, M.W.; Zieg, J.

    2009-01-01

    New Re-Os data for chalcopyrite, bornite, and pyrite from the carbonate-hosted Cu deposit at Ruby Creek (Bornite), Alaska, show extremely high Re abundances (hundreds of ppb, low ppm) and contain essentially no common Os. The Re-Os data provide the first absolute ages of ore formation for the carbonate-hosted Ruby Creek Cu-(Co) deposit and demonstrate that the Re-Os systematics of pyrite, chalcopyrite, and bornite are unaffected by greenschist metamorphism. The Re-Os data show that the main phase of Cu mineralization pre dominantly occurred at 384 ?? 4.2 Ma, with an earlier phase possibly at ???400 Ma. The Re-Os data are consistent with the observed paragenetic sequence and coincide with zircon U-Pb ages from igneous rocks within the Ambler metallogenic belt, some of which are spatially and genetically associated with regional volcanogenic massive sulfide deposits. The latter may suggest a temporal link between regional magmatism and hydrothermal mineralization in the Ambler district. The utility of bornite and chalcopyrite, in addition to pyrite, contributes to a new understanding of Re-Os geochronology and permits a refinement of the genetic model for the Ruby Creek deposit. ?? 2009 Society of Economices Geologists, Inc.

  6. Irradiation test of HAFM and tag gas samples at the standard neutron field of 'YAYOI'

    International Nuclear Information System (INIS)

    Iguchi, Tetsuo

    1997-03-01

    To check the accuracy of helium accumulation neutron fluence monitors (HAFM) as new technique for fast reactor neutron dosimetry and the applicability of tag gas activation analysis to fast reactor failed fuel detection, their samples were irradiated at the standard neutron field of the fast neutron source reactor 'YAYOI' (Nuclear Engineering Research Laboratory, University of Tokyo). Since October in 1996, the HAFM samples such as 93% enriched boron (B) powders of 1 mg and natural B powders of 10 mg contained in vanadium (V) capsule were intermittently irradiated at the reactor core center (Glory hole: Gy) and/or under the leakage neutron field from the reactor core (Fast column: FC). In addition, new V capsules filled with enriched B of 40 mg and Be of 100 mg, respectively, were put into an experimental hole through the blanket surrounding the core. These neutron fields were monitored by the activation foils consisting of Fe, Co, Ni, Au, 235 U, 237 Np etc., mainly to confirm the results obtained from 1995's preliminary works. In particular, neutron flux distributions in the vicinity of irradiated samples were measured in more detail. At the end of March in 1997, the irradiated neutron fluence have reached the goal necessary to produce the detectable number of He atoms more than ∼10 13 in each HAFM sample. Six kinds of tag gas samples, which are the mixed gases of isotopically adjusted Xe and Kr contained in SUS capsules, were separately irradiated three times at Gy under the neutron fluence of ∼10 16 n/cm 2 in average. After irradiation, γ-ray spectra were measured for each sample. Depending on the composition of tag gas mixtures, the different patterns of γ-ray peak spectra from 79 Kr, 125 Xe, etc. produced through tag gas activation were able to be clearly identified. These experimental data will be very useful for the benchmark test of tag gas activation calculation applied to the fast reactor failed fuel detection. (author)

  7. Evaluation of aluminum capsules according to ISO 9978 to irradiation of gaseous samples in nuclear reactor

    International Nuclear Information System (INIS)

    Costa, Osvaldo L. da.; Tiezzi, Rodrigo; Souza, Daiane C.B.; Feher, Anselmo; Moura, Joao A.; Souza, Carla D.; Moura, Eduardo S.; Oliveira, Henrique B.; Zeituni, Carlos A.; Rostelato, Maria Elisa C.M.

    2015-01-01

    Gas irradiation in research nuclear reactors is an important way to produce radionuclides. Although some nuclear reactors centers offer this type of service, there are few publications about capsules to irradiation of gaseous samples. This paper describes a method to fabricate and evaluate aluminum capsules to irradiate gaseous samples in nuclear reactor. A semi-circular slotted die from a hydraulic press head was modified to seal aluminum tubes. The aluminum capsules were subjected to leak detection tests, which demonstrated the accordance with standard ISO 9978. (author)

  8. Stress determination in thermally grown alumina scales using ruby luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Renusch, D.; Veal, B.W.; Koshelev, I.; Natesan, K.; Grimsditch [Argonne National Lab., IL (United States); Hou, P.Y. [Lawrence Berkeley Lab., CA (United States)

    1996-06-01

    By exploiting the strain dependence of the ruby luminescence line, we have measured the strain in alumina scales thermally grown on Fe-Cr- Al alloys. Results are compared and found to be reasonably consistent with strains determined using x rays. Oxidation studies were carried out on alloys Fe - 5Cr - 28Al and Fe - 18Cr - 10Al (at.%). Significantly different levels of strain buildup were observed in scales on these alloys. Results on similar alloys containing a ``reactive element`` (Zr or Hf) in dilute quantity are also presented. Scales on alloys containing a reactive element (RE) can support significantly higher strains than scales on RE-free alloys. With the luminescence technique, strain relief associated with spallation thresholds is readily observed.

  9. Microcomputer-based systems for automatic control of sample irradiation and chemical analysis of short-lived isotopes

    International Nuclear Information System (INIS)

    Bourret, S.C.

    1974-01-01

    Two systems resulted from the need for the study of the nuclear decay of short-lived radionuclides. Automation was required for better repeatability, speed of chemical separation after irradiation and for protection from the high radiation fields of the samples. A MCS-8 computer was used as the nucleus of the automatic sample irradiation system because the control system required an extensive multiple-sequential circuit. This approach reduced the sequential problem to a computer program. The automatic chemistry control system is a mixture of a fixed and a computer-based programmable control system. The fixed control receives the irradiated liquid sample from the reactor, extracts the liquid and disposes of the used sample container. The programmable control executes the chemistry program that the user has entered through the teletype. (U.S.)

  10. One-step in-diffusion as a result of multipulse laser irradiation of LiNbO3 single-crystalline substrates covered with thin Ti deposits on the effect of the radiation wavelength

    International Nuclear Information System (INIS)

    Ferrari, A.; Schirone, L.; Maiello, G.

    1994-05-01

    We studied Ti in-diffusion as an effect of multiple laser irradiation, in either visible of ultraviolet (u.v.) spectral ranges, of LiNbO 3 single-crystalline structures with Ti coatings of two different thickness. It is shown that while u.v. (excimer, λ approx. 308 nm) laser irradiation causes a complete expulsion of the Ti deposit, the visible (ruby, λ approx. 694.3 nm) laser irradiation at intermediate incident laser fluence (up to approx. 0.7J cm -2 ) promotes efficient Ti in-diffusion from the thin (400 A width) Ti deposit down to a micrometre range implantation depth. (author). 7 refs, 6 figs

  11. Combining 1,4-dimethoxybenzene, the major flower volatile of wild strawberry Fragaria vesca, with the aggregation pheromone of the strawberry blossom weevil Anthonomus rubi improves attraction

    DEFF Research Database (Denmark)

    Wibe, Atle; Borg-Karlson, Anna Karin; Cross, Jerry

    2014-01-01

    The aggregation pheromone of strawberry blossom weevil [Anthonomus rubi Herbst (Col.: Curculionidae)], a 1:4:1 blend of Grandlure I, II and racemic lavadulol, has been available for pest monitoring for several years but shows low attractancy. Attempts to control A.rubi using the pheromone alone...... were also unsuccessful. This paper reports the finding that addition of the major flower volatile from wild strawberry flowers [Fragaria vesca L. (Rosaceae)], 1,4-dimethoxybenzene (comprising 98% of the volatiles emitted from wild strawberry flowers), to the aggregation pheromone increased trap catches...... pest of strawberry....

  12. Characteristics of recycled and electron beam irradiated high density polyethylene samples

    International Nuclear Information System (INIS)

    Cardoso, Jessica R.; Gabriel, Leandro; Geraldo, Aurea B.C.; Moura, Eduardo

    2015-01-01

    Polymers modification by irradiation is a well-known process that allows degradation and cross-linking in concurrent events; this last is expected when an increase of mechanical properties is required. Actually, the interest of recycling and reuse of polymeric material is linked to the increase of plastics ending up in waste streams. Therefore, these both irradiation and recycling process may be conducted to allow a new use to this material that would be discarded by an improvement of its mechanical properties. In this work, the High Density Polyethylene (HDPE) matrix has been recycled five times from original substrate. The electron beam irradiation process was applied from 50 kGy to 200 kGy in both original and recycled samples; in this way, mechanical properties and thermal characteristics were evaluated. The results of applied process and material characterization are discussed. (author)

  13. Characteristics of recycled and electron beam irradiated high density polyethylene samples

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Jessica R.; Gabriel, Leandro; Geraldo, Aurea B.C.; Moura, Eduardo, E-mail: jrcardoso@ipen.br, E-mail: lgabriell@gmail.com, E-mail: ageraldo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Polymers modification by irradiation is a well-known process that allows degradation and cross-linking in concurrent events; this last is expected when an increase of mechanical properties is required. Actually, the interest of recycling and reuse of polymeric material is linked to the increase of plastics ending up in waste streams. Therefore, these both irradiation and recycling process may be conducted to allow a new use to this material that would be discarded by an improvement of its mechanical properties. In this work, the High Density Polyethylene (HDPE) matrix has been recycled five times from original substrate. The electron beam irradiation process was applied from 50 kGy to 200 kGy in both original and recycled samples; in this way, mechanical properties and thermal characteristics were evaluated. The results of applied process and material characterization are discussed. (author)

  14. O tema do amor em “Bruma (A Estrela Vermelha”, de Murilo Rubião

    Directory of Open Access Journals (Sweden)

    Ilma Socorro Gonçalves Vieira

    2014-12-01

    Full Text Available Este artigo apresenta uma análise da manifestação do amor no conto “Bruma (a estrela vermelha”, de Murilo Rubião, como sugestão de um processo individual marcado pelo anseio inconsciente de alcançar a plenitude humana. O entendimento é de que o tema do amor se apresenta associado ao do ciúme e que as inquietações vividas e narradas pelo protagonista sugerem um paradoxal sentimento que se oculta, ao mesmo tempo em que se revela, no discurso e nas imagens presentes na narrativa. A base da análise consiste na hermenêutica simbólica, conforme as pesquisas de Gilbert Durand acerca das estruturas antropológicas do imaginário, juntamente com estudos na perspectiva da semiótica das paixões, desenvolvidos por Greimas e Fontanille, além dos trabalhos de Jorge Schwartz – voltado à investigação dos traços distintivos da poética muriliana –, de Suzana Cánovas – a respeito do universo fantástico de Rubião – e de Salma Silva – sobre as formas sob as quais o tema do amor pode se apresentar no texto literário.

  15. Detection of irradiated spice in blend of irradiated and un-irradiated spices using thermoluminescence method

    International Nuclear Information System (INIS)

    Goto, Michiko; Yamazaki, Masao; Sekiguchi, Masayuki; Todoriki, Setsuko; Miyahara, Makoto

    2007-01-01

    Five blended spice sample were prepared by mixing irradiated and un-irradiated black pepper and paprika at different ratios. Blended black pepper containing 2%(w/w) of 5.4 kGy-irradiated black pepper showed no maximum at glow1. Irradiated black pepper samples, mixed to 5 or 10%(w/w), were identified as 'irradiated' or 'partially irradiated' or 'un-irradiated'. All samples with un-irradiated pepper up to 20%(w/w) were identified as irradiated'. In the case 5.0 kGy-irradiated paprika were mixed with un-irradiated paprika up to 5%(w/w), all samples were identified as irradiated'. The glow1 curves of samples, including irradiated paprika at 0.2%(w/w) or higher, exhibited a maximum between 150 and 250degC. The results suggest the existence of different critical mixing ratio for the detection of irradiation among each spices. Temperature range for integration of the TL glow intensity were compared between 70-400degC and approximate 150-250degC, and revealed that the latter temperature range was determined based on the measurement of TLD100. Although TL glow ratio in 150-250degC was lower than that of 70-400degC range, identification of irradiation was not affected. Treatment of un-irradiated black pepper and paprika with ultraviolet rays had no effect on the detection of irradiation. (author)

  16. Fabrication of SERS Active Surface on Polyimide Sample by Excimer Laser Irradiation

    Directory of Open Access Journals (Sweden)

    T. Csizmadia

    2014-01-01

    Full Text Available A possible application of excimer laser irradiation for the preparation of surface enhanced Raman spectroscopy (SERS substrate is demonstrated. A polyimide foil of 125 μm thickness was irradiated by 240 pulses of focused ArF excimer laser beam (λ = 193 nm, FWHM = 20 ns. The applied fluence was varied between 40 and 80 mJ/cm2. After laser processing, the sample was coated with 40 nm silver by PLD in order to create a conducting layer required for the SERS application. The SERS activity of the samples was tested by Raman microscopy. The Raman spectra of Rhodamine 6G aqueous solution (c=10−3 mol/dm3 were collected from the patterned and metalized areas. For areas prepared at 40–60 mJ/cm2 laser fluences, the measured Raman intensities have shown a linear dependence on the applied laser fluence, while above 60 mJ/cm2 saturation was observed. The morphology of the SERS active surface areas was investigated by scanning electron microscopy. Finite element modeling was performed in order to simulate the laser-absorption induced heating of the polyimide foil. The simulation resulted in the temporal and spatial distribution of the estimated temperature in the irradiated polyimide sample, which are important for understanding the structure formation process.

  17. Investigation of the effects of irradiation for quarantine treatment purposes on food quality and hygiene in citrus fruits

    International Nuclear Information System (INIS)

    2010-01-01

    Mediterranean fruit fly (Ceratitis capitata) is a major problem in citrus production sector in Turkey. In order to overcome this problem, required irradiation doses were investigated for the quarantine treatment for 'Yafa' orange (Citrus sinensis (L) Osb.), 'Star ruby' grapefruit (Citrus paradisi Macf.); 'Satsuma' tangerine (Citrus reticulata Blanco) in this project. Chemical, physical and microbiological properties of unirradiated and irradiated (0.5, 1.0 and 1.5 kGy) fruits were determined in terms of weight loss, water soluble dry matter, pH, titratable acidity, alcohol insoluble pectin, apparent color of fruits, reducing sugar, total carotenoid, flavonoid, vitamin C contents, sensory properties of fruits, total aerob mesophilic bacteria and total yeast and mould counts of fruits. Results showed that, 0.1 kGy gamma irradiation dose is sufficient for effective quarantine treatment against the Mediterranean fruit fly in citrus fruits, low dose irradiation (≤1.0 kGy) applications had no detrimental effects on citrus fruits' quality except tangerines, microbial load of fruits were seriously affected by irradiation at 1.0 kGy. In addition, under this work we noticed that, irradiated citrus fruits could be detected by using DNA comet analysis method.

  18. Ruby lidar observations and trajectory analysis of stratospheric aerosols injected by the volcanic eruptions of El Chichon

    Science.gov (United States)

    Uchino, O.; Tabata, T.; Akita, I.; Okada, Y.; Naito, K.

    1985-01-01

    Large amounts of aerosol particles and gases were injected into the lower stratosphere by the violet volcanic eruptions of El Chichon on March 28, and April 3 and 4, 1982. Observational results obtained by a ruby lidar at Tsukuba (36.1 deg N, 140.1 deg E) are shown, and some points of latitude dispersion processes of aerosols are discussed.

  19. Temporal migration patterns between natal locations of ruby-throated hummingbirds (Archilochus colubris) and their Gulf Coast stopover site.

    Science.gov (United States)

    Zenzal, Theodore J; Contina, Andrea J; Kelly, Jeffrey F; Moore, Frank R

    2018-01-01

    Autumn latitudinal migrations generally exhibit one of two different temporal migration patterns: type 1 where southern populations migrate south before northern populations, or type 2 where northern populations overtake southern populations en route . The ruby-throated hummingbird ( Archilochus colubris ) is a species with an expansive breeding range, which allows opportunities to examine variation in the timing of migration. Our objective was to determine a relationship between natal origin of ruby-throated hummingbirds and arrival at a Gulf coast stopover site; and if so, what factors, such as differences in body size across the range as well as the cost of migration, might drive such a pattern. To carry out our objectives, we captured hummingbirds at a coastal stopover site during autumn migration, at which time we collected feathers from juveniles for analysis of hydrogen stable isotopes. Using the hydrogen stable isotope gradient of precipitation across North America and published hydrogen isotope values of feathers from populations of breeding ruby-throated hummingbirds, we assigned migrants to probable natal latitudes. Our results confirm that individuals from across the range (30-50° N) stopover along the Gulf of Mexico and there is a positive relationship between arrival day and latitude, suggesting a type 1 migration pattern. We also found no relationship between fuel load (proxy for migration cost) or fat-free body mass (proxy for body size) and natal latitude. Our results, coupled with previous work on the spatial migration patterns of hummingbirds, show a type 1 chain migration pattern. While the mechanisms we tested do not seem to influence the evolution of migratory patterns, other factors such as resource availability may play a prominent role in the evolution of this migration system.

  20. ASPIRE: An automated sample positioning and irradiation system for radiation biology experiments at Inter University Accelerator Centre, New Delhi

    International Nuclear Information System (INIS)

    Kothari, Ashok; Barua, P.; Archunan, M.; Rani, Kusum; Subramanian, E.T.; Pujari, Geetanjali; Kaur, Harminder; Satyanarayanan, V.V.V.; Sarma, Asitikantha; Avasthi, D.K.

    2015-01-01

    An automated irradiation setup for biology samples has been built at Inter University Accelerator Centre (IUAC), New Delhi, India. It can automatically load and unload 20 biology samples in a run of experiment. It takes about 20 min [2% of the cell doubling time] to irradiate all the 20 samples. Cell doubling time is the time taken by the cells (kept in the medium) to grow double in numbers. The cells in the samples keep growing during entire of the experiment. The fluence irradiated to the samples is measured with two silicon surface barrier detectors. Tests show that the uniformity of fluence and dose of heavy ions reaches to 2% at the sample area in diameter of 40 mm. The accuracy of mean fluence at the center of the target area is within 1%. The irradiation setup can be used to the studies of radiation therapy, radiation dosimetry and molecular biology at the heavy ion accelerator. - Highlights: • Automated positioning and irradiation setup for biology samples at IUAC is built. • Loading and unloading of 20 biology samples can be automatically carried out. • Biologicals cells keep growing during entire experiment. • Fluence and dose of heavy ions are measured by two silicon barrier detectors. • Uniformity of fluence and dose of heavy ions at sample position reaches to 2%

  1. Thermal shock testing of ceramics with pulsed laser irradiation

    International Nuclear Information System (INIS)

    Benz, R.; Naoumidis, A.; Nickel, H.

    1986-04-01

    Arguments are presented showing that the resistance to thermal stressing (''thermal shock'') under pulsed thermal energy deposition by various kinds of beam irradiations is approximately proportional to Φ a √tp, where Φ a is the absorbed power density and tp is the pulse length, under conditions of diffusivity controlled spreading of heat. In practical beam irradiation testing, incident power density, Φ, is reported. To evaluate the usefulness of Φ√tp as an approximation to Φ a √tp, damage threshold values are reviewed for different kinds of beams (electron, proton, and laser) for a range of tp values 5x10 -6 to 2 s. Ruby laser beam irradiation tests were made on the following ceramics: AlN, BN, graphite, αSiC, β-SiC coated graphites, (α+β)Si 3 N 4 , CVD (chemical vapor deposition) TiC coated graphite, CVD TiC coated Mo, and CVD TiN coated IN 625. The identified failure mechanisms are: 1. plastic flow followed by tensile and bend fracturing, 2. chemical decomposition, 3. melting, and 4. loss by thermal spallation. In view of the theoretical approximations and the neglect of reflection losses there is reasonable accord between the damage threshold Φ√tp values from the laser, electron, and proton beam tests. (orig./IHOE)

  2. Research of pneumatic control transmission system for small irradiation samples

    International Nuclear Information System (INIS)

    Bai Zhongxiong; Zhang Haibing; Rong Ru; Zhang Tao

    2008-01-01

    In order to reduce the absorbed dose damage for the operator, pneumatic control has been adopted to realize the rapid transmission of small irradiation samples. On/off of pneumatic circuit and directions for the rapid transmission system are controlled by the electrical control part. The main program initializes the system and detects the location of the manual/automatic change-over switch, and call for the corresponding subprogram to achieve the automatic or manual operation. Automatic subprogram achieves the automatic sample transmission; Manual subprogram completes the deflation, and back and forth movement of the radiation samples. This paper introduces in detail the implementation of the system, in terms of both hardware and software design. (authors)

  3. Design and building of a homemade sample changer for automation of the irradiation in neutron activation analysis technique

    International Nuclear Information System (INIS)

    Gago, Javier; Hernandez, Yuri; Baltuano, Oscar; Bedregal, Patricia; Lopez, Yon; Urquizo, Rafael

    2014-01-01

    Because the RP-10 research reactor operates during weekends, it was necessary to design and build a sample changer for irradiation as part of the automation process of neutron activation analysis technique. The device is formed by an aluminum turntable disk which can accommodate 19 polyethylene capsules, containing samples to be sent using the pneumatic transfer system from the laboratory to the irradiation position. The system is operate by a control switchboard to send and return capsules in a variable preset time and by two different ways, allowing the determination of short, medium and long lived radionuclides. Also another mechanism is designed called 'exchange valve' for changing travel paths (pipelines) allowing the irradiated samples to be stored for a longer time in the reactor hall. The system design has allowed complete automation of this technique, enabling the irradiation of samples without the presence of an analyst. The design, construction and operation of the device is described and presented in this article. (authors).

  4. Crystalline Chromium Doped Aluminum Oxide (RUBY) Use as a Luminescent Screen for Proton Beams

    International Nuclear Information System (INIS)

    Brown, K. A.; Gassner, D. M.

    1999-01-01

    In the search for a better luminescent screen material, the authors tested pieces of mono-crystalline chromium doped aluminum oxide (more commonly known as a ruby) using a 24 GeV proton beam. Due to the large variations in beam intensity and species which are run at the Alternating Gradient Synchrotron (AGS), they hope to find a material which can sufficiently luminesce, is compatible in vacuum, and maintain its performance level over extended use. Results from frame grabbed video camera images using a variety of neutral density filters are presented

  5. Independent CO2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels, Task 2.50.05

    International Nuclear Information System (INIS)

    Stojic, M.; Pavicevic, M.

    1964-01-01

    This report contains the following volumes V and VI of the Project 'Independent CO 2 loop for cooling the samples irradiated in RA reactor vertical experimental channels': Design project of the dosimetry control system in the independent CO 2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels, and Safety report for the Independent CO 2 loop for cooling the samples irradiated in the RA reactor vertical experimental channels [sr

  6. ESR-based Identification of Radiation-Induced Free Radicals in Gamma-Irradiated Basil and Clove Using Different Sample Pre-Treatments

    International Nuclear Information System (INIS)

    Kwak, J.Y.; Ahn, J.J.; Kashif Akram; Kwon, J.H.

    2012-01-01

    An improved detection of radiation-induced paramagnetic faults was developed to identify the irradiation status of basil and clove. The effectiveness of different sample pretreatments, including freeze-drying (FD), oven-drying (OD), alcoholic-extraction (AE), and water-washing and alcoholic-extraction (WAE), were examined. All non-irradiated samples showed a single central signal (g 0 = 2.006), whereas radicals representing two additional side peaks (g 1 = 2.023 and g 2 = 1.986) with a mutual distance of 6 mT were detected in the irradiated samples. AE and WAE produced the best results for irradiated clove in terms of intensities of radiation-specific ESR signals and their ratios to the central signal. However, FD provided the highest intensities of radiation-specific ESR signals for basil, whereas their ratios to the major signal were better in the cases of AE and WAE. Signal noise, particularly due to Mn 2+ signals, was observed, whereas it decreased in AE and WAE pretreatments. Based on our results, AE and WAE can improve the detection conditions for radiation-specific ESR signals in irradiated samples. (author)

  7. MCNPX calculations of dose rate distribution inside samples treated in the research gamma irradiating facility at CTEx

    Energy Technology Data Exchange (ETDEWEB)

    Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G., E-mail: tiagorusin@ime.eb.b, E-mail: rebello@ime.eb.b, E-mail: vellozo@cbpf.b, E-mail: renatoguedes@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear; Vital, Helio C., E-mail: vital@ctex.eb.b [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (Brazil); Silva, Ademir X., E-mail: ademir@con.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear

    2011-07-01

    A cavity-type cesium-137 research irradiating facility at CTEx has been modeled by using the Monte Carlo code MCNPX. The irradiator has been daily used in experiments to optimize the use of ionizing radiation for conservation of many kinds of food and to improve materials properties. In order to correlate the effects of the treatment, average doses have been calculated for each irradiated sample, accounting for the measured dose rate distribution in the irradiating chambers. However that approach is only approximate, being subject to significant systematic errors due to the heterogeneous internal structure of most samples that can lead to large anisotropy in attenuation and Compton scattering properties across the media. Thus this work is aimed at further investigating such uncertainties by calculating the dose rate distribution inside the items treated such that a more accurate and representative estimate of the total absorbed dose can be determined for later use in the effects-versus-dose correlation curves. Samples of different simplified geometries and densities (spheres, cylinders, and parallelepipeds), have been modeled to evaluate internal dose rate distributions within the volume of the samples and the overall effect on the average dose. (author)

  8. MCNPX calculations of dose rate distribution inside samples treated in the research gamma irradiating facility at CTEx

    International Nuclear Information System (INIS)

    Rusin, Tiago; Rebello, Wilson F.; Vellozo, Sergio O.; Gomes, Renato G.; Silva, Ademir X.

    2011-01-01

    A cavity-type cesium-137 research irradiating facility at CTEx has been modeled by using the Monte Carlo code MCNPX. The irradiator has been daily used in experiments to optimize the use of ionizing radiation for conservation of many kinds of food and to improve materials properties. In order to correlate the effects of the treatment, average doses have been calculated for each irradiated sample, accounting for the measured dose rate distribution in the irradiating chambers. However that approach is only approximate, being subject to significant systematic errors due to the heterogeneous internal structure of most samples that can lead to large anisotropy in attenuation and Compton scattering properties across the media. Thus this work is aimed at further investigating such uncertainties by calculating the dose rate distribution inside the items treated such that a more accurate and representative estimate of the total absorbed dose can be determined for later use in the effects-versus-dose correlation curves. Samples of different simplified geometries and densities (spheres, cylinders, and parallelepipeds), have been modeled to evaluate internal dose rate distributions within the volume of the samples and the overall effect on the average dose. (author)

  9. Effect of gamma irradiation and storage on lutein and zeaxanthin in liquid, frozen and dried egg yolk samples

    International Nuclear Information System (INIS)

    Mine Uygun-Saribay; Ece Ergun; Turhan Koeseoglu

    2014-01-01

    The aim of this study was to monitor the effects of gamma irradiation and storage on the content of lutein and zeaxanthin in egg yolk samples. Liquid, frozen and dried egg samples were subjected to gamma irradiation doses of 0, 1, 2 and 3 kGy followed by storage of liquid samples at +4 ± 1 deg C for 21 days, frozen samples at -18 ± 1 deg C and dried samples at room temperature for 1 year. The xanthophyll concentrations were determined by high-performance liquid chromatography-diode array detector. It was observed that concentrations of both lutein and zeaxanthin were decreased significantly (P < 0.05) after irradiation and during storage. The mechanism for radiation-induced degradation was proposed as radical formation which initiate chain reactions. It was suggested that during storage active radical species and oxygen caused the degradation. (author)

  10. Manipulation of Zeeman coherence in solids at room temperature: Ramsey interference in the coherent-population-trapping spectrum of ruby

    International Nuclear Information System (INIS)

    Kolesov, Roman; Scully, Marlan O.; Kocharovskaya, Olga

    2006-01-01

    Coherent population trapping (CPT) in a three-level atomic medium pumped by two subsequent short optical pulses is considered under the condition of negligible population decay from the excited optical state. It is shown that the amount of atomic population transferred to the excited state by the combined action of the pulses strongly depends on the phase of the ground-state coherence excited by the first pulse at the arrival time of the second pulse. Oscillatory behavior of optical excitation efficiency on the time delay between the pulses is predicted. It is also shown that saturating optical pulses can produce population inversion in a resonantly pumped quasi-two-level system. A class of solid materials in which the predicted phenomena can be observed at room temperature is found. It includes some rare-earth and transition-metal doped dielectric crystals where Orbach relaxation between ground-state Zeeman states is suppressed: ruby, alexandrite, and several others. On the basis of the theoretical predictions, experimental observation of Ramsey fringes in CPT spectrum of ruby is reported

  11. Characterization of Irradiated and Non-Irradiated Rubber from Automotive Scrap Tires

    Science.gov (United States)

    Souza, Clécia Moura; Silva, Leonardo G.

    The aim of this work was to characterize the samples of irradiated and non-irradiated rubber from automotive scrap tires. Rubber samples from scrap tires were irradiated at irradiation doses of 200, 400 and 600kGy in an electron beam accelerator. Subsequently, both the irradiated and non-irradiated samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, and Fourier transform infrared (FTIR) spectrophotometry.

  12. Reduction of Staphylococcus Spp. in jerked beef samples after irradiation with Co-60

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marcio de Albuquerque, E-mail: marcioalbuquerquesilva@gmail.com [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Laboratorio de Genomica Funcional e Bioinformatica; Costa, Maria Claudia V.Vicalvi; Junior, Carlos Eduardo de O.C.; Solidonio, Evelyne G.; Sena, Kesia Xisto F.R. de; Colaco, Waldeciro, E-mail: claudiavicalvi@hotmail.com, E-mail: oliveiracosta@msn.com, E-mail: evelyne_solidonio@yahoo.com.br, E-mail: wcolaco@ufpe.com.br, E-mail: k.xisto@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife (Brazil)

    2015-07-01

    This work aimed to isolate and identify Staphylococcus genus microorganisms in jerked beef before and after radiation doses between 2, 4 and 6kGy. Jerked beef samples were obtained on a Recife-PE supermarket network and divided into three lots. Under sterile conditions, the meat was cut and weighed. Sub-samples were assigned to the control group and to the irradiation source of cobalt-60 on doses of 2, 4 and 6kGy. The sub-samples were added to an Erlenmeyer flask with 225 ml of sterile water and stirred for 15 minutes creating wash water, and another part was added to an Erlenmeyer flask with 225 ml of sterile distilled water that was at rest at room temperature for 14 hours there is the formation of a water desalting. 1μL aliquots of this water was removed and sown by depletion in sheep blood agar medium and incubated at 35 °C for 24 hours for analysis of bacterial growth. After Gram staining colonies classified as Gram positive arranged in bunches were subjected to biochemical tests for identification. Were isolated and identified 94 strains of the genus Staphylococcus being 72 (76%) of the control group and 22 (24%) after irradiation. Of the 22 isolates, after irradiation, with 2 kGy 7 species were identified as Staphylococcus succinus, Staphylococcus carnosus sub. carnosus, Staphylococcus fleurettii, Staphylococcus saprophyticus sub. saprophyticus, Staphylococcus simulans, Staphylococcus auricularis all coagulase negative and coagulase positive Staphylococcus aureus sub. anaerobius. At a dose of 4kGy were identified six species: Staphylococcus epidermidis, Staphylococcus xylosus, Staphylococcus intermedius, Staphylococcus warneri, Staphylococcus fleurettii, Staphylococcus aureus sub. anaerobius. Staphylococcus simulans, Staphylococcus saprophyticus sub. saprophyticus, and Staphylococcus lugdunensis were isolated and identified after a dose of 6 kGy. Was observed that irradiation significantly reduced microbial load, and increased dose decreased the number of

  13. Reduction of Staphylococcus Spp. in jerked beef samples after irradiation with Co-60

    International Nuclear Information System (INIS)

    Silva, Marcio de Albuquerque

    2015-01-01

    This work aimed to isolate and identify Staphylococcus genus microorganisms in jerked beef before and after radiation doses between 2, 4 and 6kGy. Jerked beef samples were obtained on a Recife-PE supermarket network and divided into three lots. Under sterile conditions, the meat was cut and weighed. Sub-samples were assigned to the control group and to the irradiation source of cobalt-60 on doses of 2, 4 and 6kGy. The sub-samples were added to an Erlenmeyer flask with 225 ml of sterile water and stirred for 15 minutes creating wash water, and another part was added to an Erlenmeyer flask with 225 ml of sterile distilled water that was at rest at room temperature for 14 hours there is the formation of a water desalting. 1μL aliquots of this water was removed and sown by depletion in sheep blood agar medium and incubated at 35 °C for 24 hours for analysis of bacterial growth. After Gram staining colonies classified as Gram positive arranged in bunches were subjected to biochemical tests for identification. Were isolated and identified 94 strains of the genus Staphylococcus being 72 (76%) of the control group and 22 (24%) after irradiation. Of the 22 isolates, after irradiation, with 2 kGy 7 species were identified as Staphylococcus succinus, Staphylococcus carnosus sub. carnosus, Staphylococcus fleurettii, Staphylococcus saprophyticus sub. saprophyticus, Staphylococcus simulans, Staphylococcus auricularis all coagulase negative and coagulase positive Staphylococcus aureus sub. anaerobius. At a dose of 4kGy were identified six species: Staphylococcus epidermidis, Staphylococcus xylosus, Staphylococcus intermedius, Staphylococcus warneri, Staphylococcus fleurettii, Staphylococcus aureus sub. anaerobius. Staphylococcus simulans, Staphylococcus saprophyticus sub. saprophyticus, and Staphylococcus lugdunensis were isolated and identified after a dose of 6 kGy. Was observed that irradiation significantly reduced microbial load, and increased dose decreased the number of

  14. Determination of irradiated reactor uranium in soil samples in Belarus using 236U as irradiated uranium tracer.

    Science.gov (United States)

    Mironov, Vladislav P; Matusevich, Janna L; Kudrjashov, Vladimir P; Boulyga, Sergei F; Becker, J Sabine

    2002-12-01

    This work presents experimental results on the distribution of irradiated reactor uranium from fallout after the accident at Chernobyl Nuclear Power Plant (NPP) in comparison to natural uranium distribution in different soil types. Oxidation processes and vertical migration of irradiated uranium in soils typical of the 30 km relocation area around Chernobyl NPP were studied using 236U as the tracer for irradiated reactor uranium and inductively coupled plasma mass spectrometry as the analytical method for uranium isotope ratio measurements. Measurements of natural uranium yielded significant variations of its concentration in upper soil layers from 2 x 10(-7) g g(-1) to 3.4 x 10(-6) g g(-1). Concentrations of irradiated uranium in the upper 0-10 cm soil layers at the investigated sampling sites varied from 5 x 10(-12) g g(-1) to 2 x 10(-6) g g(-1) depending on the distance from Chernobyl NPP. In the majority of investigated soil profiles 78% to 97% of irradiated "Chernobyl" uranium is still contained in the upper 0-10 cm soil layers. The physical and chemical characteristics of the soil do not have any significant influence on processes of fuel particle destruction. Results obtained using carbonate leaching of 236U confirmed that more than 60% of irradiated "Chernobyl" uranium is still in a tetravalent form, ie. it is included in the fuel matrix (non-oxidized fuel UO2). The average value of the destruction rate of fuel particles determined for the Western radioactive trace (k = 0.030 +/- 0.005 yr(-1)) and for the Northern radioactive trace (k = 0.035 + 0.009 yr(-1)) coincide within experimental errors. Use of leaching of fission products in comparison to leaching of uranium for study of the destruction rate of fuel particles yielded poor coincidence due to the fact that use of fission products does not take into account differences in the chemical properties of fission products and fuel matrix (uranium).

  15. DNA damage focus analysis in blood samples of minipigs reveals acute partial body irradiation.

    Directory of Open Access Journals (Sweden)

    Andreas Lamkowski

    Full Text Available Radiation accidents frequently involve acute high dose partial body irradiation leading to victims with radiation sickness and cutaneous radiation syndrome that implements radiation-induced cell death. Cells that are not lethally hit seek to repair ionizing radiation (IR induced damage, albeit at the expense of an increased risk of mutation and tumor formation due to misrepair of IR-induced DNA double strand breaks (DSBs. The response to DNA damage includes phosphorylation of histone H2AX in the vicinity of DSBs, creating foci in the nucleus whose enumeration can serve as a radiation biodosimeter. Here, we investigated γH2AX and DNA repair foci in peripheral blood lymphocytes of Göttingen minipigs that experienced acute partial body irradiation (PBI with 49 Gy (± 6% Co-60 γ-rays of the upper lumbar region. Blood samples taken 4, 24 and 168 hours post PBI were subjected to γ-H2AX, 53BP1 and MRE11 focus enumeration. Peripheral blood lymphocytes (PBL of 49 Gy partial body irradiated minipigs were found to display 1-8 DNA damage foci/cell. These PBL values significantly deceed the high foci numbers observed in keratinocyte nuclei of the directly γ-irradiated minipig skin regions, indicating a limited resident time of PBL in the exposed tissue volume. Nonetheless, PBL samples obtained 4 h post IR in average contained 2.2% of cells displaying a pan-γH2AX signal, suggesting that these received a higher IR dose. Moreover, dispersion analysis indicated partial body irradiation for all 13 minipigs at 4 h post IR. While dose reconstruction using γH2AX DNA repair foci in lymphocytes after in vivo PBI represents a challenge, the DNA damage focus assay may serve as a rapid, first line indicator of radiation exposure. The occurrence of PBLs with pan-γH2AX staining and of cells with relatively high foci numbers that skew a Poisson distribution may be taken as indicator of acute high dose partial body irradiation, particularly when samples are available

  16. Burn-up determination of irradiated thoria samples by isotope dilution-thermal ionisation mass spectrometry

    International Nuclear Information System (INIS)

    Aggarwal, S.K.; Jaison, P.G.; Telmore, V.M.; Shah, R.V.; Sant, V.L.; Sasibhushan, K.; Parab, A.R.; Alamelu, D.

    2010-03-01

    Burn-up was determined experimentally using thermal ionization mass spectrometry for two samples from ThO 2 bundles irradiated in KAPS-2. This involved quantitative dissolution of the irradiated fuel samples followed by separation and determination of Th, U and a stable fission product burn-up monitor in the dissolved fuel solution. Stable fission product 148 Nd was used as a burn-up monitor for determining the number of fissions. Isotope Dilution-Thermal Ionisation Mass Spectrometry (ID-TIMS) using natural U, 229 Th and enriched 142 Nd as spikes was employed for the determination of U, Th and Nd, respectively. Atom % fission values of 1.25 ± 0.03 were obtained for both the samples. 232 U content in 233 U determined by alpha spectrometry was about 500 ppm and this was higher by a factor of 5 compared to the theoretically predicted value by ORIGEN-2 code. (author)

  17. Characterization and Identification of Gamma-Irradiated Kimchi Cabbage and Broccoli by Electron Spin Resonance Spectroscopy using Different Sample Pre-treatments

    International Nuclear Information System (INIS)

    Kwak, J.Y.; Ahn, J.J.; Kashif Akram; Kim, G.R.; Kwon, J.H.

    2012-01-01

    Electron spin resonance (ESR) spectroscopy of gamma-irradiated fresh broccoli and kimchi cabbage was conducted to identify their irradiation history. Different pretreatments, such as freeze-drying (FD), oven-drying (OD), alcoholic-drying (ALD), and water-washing and alcoholic-drying (WAD) were used to lower the moisture contents of the samples prior to ESR analysis. The non-irradiated samples exhibited a single central signal (g 0 = 2.0007) with clear effect of Mn 2+ , especially in kimchi cabbage. Upon irradiation, there was an increase in the intensity of the central signal, and two side peaks, mutually spaced at 6 mT, were also observed. These side peaks with g 1 (left) = 2.023 and g 2 (right) = 1.985 were attributed to radiation-induced cellulose radicals. Leaf and stem in broccoli, and root and stem in kimchi cabbage provided good ESR signal responses upon irradiation. The signal noise was reduced in case of ALD and WAD pretreatments, particularly due to Mn 2+ signals. The ALD treatment was found most feasible to detect the improved ESR spectra in the irradiated samples. (author)

  18. Biological samples positioning device for irradiations on a radial channel at the nuclear research reactor

    International Nuclear Information System (INIS)

    Rodriguez Gual, Maritza; Mas Milian, Felix; Deppman, Airton; Pinto Coelho, Paulo Rogerio

    2010-01-01

    For the demand of an experimental device for biological samples positioning system for irradiations on a radial channel at the nuclear research reactor in operation was constructed and started up a device for the place and remove of the biological samples from the irradiation channels without interrupting the operation of the reactor. The economical valuations are effected comparing with another type of device with the same functions. This work formed part of an international project between Cuba and Brazil that undertook the study of the induced damages by various types of ionizing radiation in DNA molecules. Was experimentally tested the proposed solution, which demonstrates the practical validity of the device. As a result of the work, the experimental device for biological samples irradiations are installed and operating in the radial beam hole No3(BH3) for more than five years at the IEA-R1 Brazilian research reactor according to the solicited requirements the device. The designed device increases considerably the type of studies can be conducted in this reactor. Its practical application in research taking place in that facility, in the field of radiobiology and dosimetry, and so on is immediate

  19. Reflectivity of the gyroid biophotonic crystals in the ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi

    OpenAIRE

    Michielsen, K.; De Raedt, H.; Stavenga, D. G.

    2009-01-01

    We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization ef...

  20. The Influence of Different Interstock Lengths of Minneola Tanjelo on Photosynthetic Parameters and Fruit Yield of Star Ruby Grapefruit

    Directory of Open Access Journals (Sweden)

    Bilge Yılmaz

    2014-05-01

    Full Text Available In this study, Minneola Tangelo hybrid, a cross of grapefruit and mandarin (Duncan grapefruit x Dancy mandarin, used as interstock to Star Ruby grapefruit with different lengths. Effects of different interstock lengths on fruit yield and quality, plant development and photosynthetic parameters were investigated. According to the results, different interstock lengths significantly affected fruit yield and size. The highest fruit yield was determined in T-M20-S whereas the lowest was on T-M5-S. The highest fruit size were determined in Star Ruby fruits on T-M5-S and T-M40-S whereas the lowest on T-M20-S and T-S (control. T-M40-S and T-M20-S treatments markedly reduced stem diameter and tree canopy in comparison to other treatments and control. Usage of different interstock lengths did not significantly affected some of fruit quality traits, net photosynthetic rate, stomatal conductance, leaf transpiration rate, leaf water usage efficiency and leaf chlorophyll concentration. In regards to seasonal changes, net photosynthetic rate were higher in spring and summer seasons then winter and fall seasons.

  1. Laser-induced defect formation in ZnxCd1-xSe solid solutions and its influence on electrophysical properties

    International Nuclear Information System (INIS)

    Baidullaeva, A.; Mozol, P.E.; Korsunskaya, N.E.; Gnatyuk, V.A.

    1991-01-01

    The influence of irradiation with ruby laser emission pulses of 2x10 -8 s in duration on electrical, photoelectrical, and luminescent properties of single crystals of Zn x Cd 1-x Se solid solutions (SS) is investigated. An increase of the conductivity and photosensitivity in irradiated samples is observed, which is explained by the formation of r-centres, which are metal vacancies counterbalanced by shallow donor centres. Also, a layer with a wider forbidden gap forms in the subsurface region of Zn x Cd 1-x Se SS crystals after irradiation. The composition changes by 3 to 5% towards an increase of x. (orig.)

  2. Measurement of characteristic prompt gamma rays emitted from oxygen and carbon in tissue-equivalent samples during proton beam irradiation.

    Science.gov (United States)

    Polf, Jerimy C; Panthi, Rajesh; Mackin, Dennis S; McCleskey, Matt; Saastamoinen, Antti; Roeder, Brian T; Beddar, Sam

    2013-09-07

    The purpose of this work was to characterize how prompt gamma (PG) emission from tissue changes as a function of carbon and oxygen concentration, and to assess the feasibility of determining elemental concentration in tissues irradiated with proton beams. For this study, four tissue-equivalent water-sucrose samples with differing densities and concentrations of carbon, hydrogen, and oxygen were irradiated with a 48 MeV proton pencil beam. The PG spectrum emitted from each sample was measured using a high-purity germanium detector, and the absolute detection efficiency of the detector, average beam current, and delivered dose distribution were also measured. Changes to the total PG emission from (12)C (4.44 MeV) and (16)O (6.13 MeV) per incident proton and per Gray of absorbed dose were characterized as a function of carbon and oxygen concentration in the sample. The intensity of the 4.44 MeV PG emission per incident proton was found to be nearly constant for all samples regardless of their carbon concentration. However, we found that the 6.13 MeV PG emission increased linearly with the total amount (in grams) of oxygen irradiated in the sample. From the measured PG data, we determined that 1.64 × 10(7) oxygen PGs were emitted per gram of oxygen irradiated per Gray of absorbed dose delivered with a 48 MeV proton beam. These results indicate that the 6.13 MeV PG emission from (16)O is proportional to the concentration of oxygen in tissue irradiated with proton beams, showing that it is possible to determine the concentration of oxygen within tissues irradiated with proton beams by measuring (16)O PG emission.

  3. Ethephon use and application timing of abscisic acid for improving color of 'Rubi' table grape

    Directory of Open Access Journals (Sweden)

    Sergio Ruffo Roberto

    2013-07-01

    Full Text Available The objective of this work was to evaluate the effect of ethephon and of abscisic acid (ABA application timing on the color of 'Rubi' Table grape. Eight treatments were evaluated: control, without application; ethephon 500 mg L‑1 applied seven days after veraison (7 DAV; and two concentrations of ABA (200 and 400 mg L‑1 arranged with three application timings at 7 DAV, at 15 days before harvest (DBH, and at 7 DAV + 15 DBH. ABA does not modify physical‑chemical characteristics of the cluster and improves the color of grapes, especially when applied twice (7 DAV + 15 DBH at the concentration of 400 mg L‑1.

  4. Evaluation of dose exposure from irradiated samples at TRIGA PUSPATI reactor (RTP)

    International Nuclear Information System (INIS)

    Muhd Husamuddin Abdul Khalil; Julia Abdul Karim; Naim Syauqi Hamzah; Mohamad Hairie Rabir; Mohd Amin Sharifuldin Salleh

    2010-01-01

    An evaluation has been made to data of irradiated samples for the type of sample requested for activation at RTP. Sample types are grouped with percentage of total throughputs to rule out the weight percent of every respective group. The database consists of radionuclide inventory of short, intermediate and long half-life and high activity radionuclides such as Br and Au have been identified. Evaluation of gamma exposure using Micro shield has also been made to pattern the trend of gamma exposure at experimental facilities and to ensure radiological effect towards safety and health is limited per Radiation Protection (Basic Safety Standard) Regulation 1988. This analysis places an important parameter to improve the design accuracy of shielding design in assuring safety, reliability and economy. (author)

  5. Irradiation and Post-Irradiation Storage of Chicken: Effects on Fat and Proteins

    International Nuclear Information System (INIS)

    Abou-Tarboush, H.M.; Al-Kahtani, H.A.; Abou-Arab, A.A.; Atia, M.; Bajaber, A.S.; Ahmed, M.A.; El-Mojaddidi, M.A.

    1997-01-01

    Chicken were subjected to gamma irradiation doses of 2.5, 5.0, 7.5 and 10.0 KGy and post-irradiation storage of 21 days at 4±2º. The effects on fat and protein of chicken were studied. Rate of formation of total volatile basic-nitrogen was less in irradiated samples particularly in samples treated with 5.0KGy during the entire storage. Fatty acid profiles of chicken lipids were not significantly (P≤ 0.05) affected by irradiation especially at doses of 5.0 KGy. However, irradiation caused a large increase in thiobarbituric acid (TBA) values which continued gradually during storage. Changes in amino acids were minimal. Irradiated and unirradiated samples showed the appearance of protein subunits with molecular weights in the range of 10.0 to 88.0 and 10.0 to 67.0 KD, respectively. No changes were observed in the sarcoplasmic protein but the intensity of bands in all irradiated samples decreased after 21 days of storage

  6. Efeitos do paclobutrazol na fertilidade de gemas e no crescimento dos ramos de videiras cv Rubi Effects of paclobutrazol on bud fertility and shoot growth of grapevine cv Rubi

    Directory of Open Access Journals (Sweden)

    Renato Vasconcelos Botelho

    2004-08-01

    Full Text Available A baixa fertilidade de gemas tem sido um dos fatores limitantes da produção em vinhedos do Estado de São Paulo, estando este problema relacionado, em muitos casos, ao excesso de vigor das plantas. Neste contexto, um experimento foi conduzido em vinhedo comercial da cultivar de uva de mesa Rubi, localizado no município de Palmeira D'Oeste (SP. O delineamento experimental foi em blocos casualizados, com seis tratamentos e quatro repetições. Os ramos foram pulverizados com soluções de paclobutrazol nas doses de 0; 500; 1.000; 1.500; 2.000 e 2.500 mg L-1, no estádio de 5ª folha. As variáveis avaliadas foram: porcentagem de gemas férteis, porcentagem de gemas mortas, diâmetro de internódios e massa fresca e comprimento dos ramos. Aplicações de paclobutrazol reduziram o diâmetro dos internódios e a massa e o comprimento dos ramos. A porcentagem de gemas férteis também foi diminuída, possivelmente pela redução dos níveis endógenos de giberelina necessários para o processo de formação do primórdio indiferenciado.The low bud fertility has been one of the most limiting factors in vineyards at São Paulo State, and this problem has been correlated, in many cases, to the excess of plant vigor. In this context, a trial was carried out in a commercial vineyard of 'Rubi' table grape, located at Palmeira D'Oeste (SP, Brazil. The experimental design was in complete randomized blocks with six treatments and four replications. The vine shoots were sprayed with paclobutrazol at 0; 500; 1,000; 1,500; 2,000 and 2,500 mgL-1, at the fifth leaf phenological stage. The variables evaluated were: percentage of fertile buds; percentage of bud necrosis; fresh weight and length of shoots and diameter of internodes. Applications of paclobutrazol reduced the weight and the length of shoots and the internodes diameter. The percentage of fertile buds was also reduced, probably due to the decreasing in endogenous gibberellin levels necessary for

  7. Modified fuel channel for sample irradiation at the RB reactor

    International Nuclear Information System (INIS)

    Pesic, M.; Markovic, H.; Sokcic, M.; Miric, I.; Prokic, M.; Strugar, P.

    1983-01-01

    Fuel channel of 80% enriched UO 2 at RB reactor in Boris Kidric Institute of nuclear sciences is modified for sample irradiation in the fast neutron field. Maximum sample diameter is 25 mm and length up to 100 mm. Characteristics of neutron as well as gamma radiation fields of this new experimental channel are investigated. In the center of channel, the main contribution to the total neutron absorbed dose i.e. 0.29 Gy per 1 Wh of reactor operation, is due to the fast neutron spectrum component. Only 0.05 Gy and 0.07 Gy in the total neutron absorbed dose are due to epithermal and thermal neutrons respectively. At the same time gamma absorption dose is 0.35 Gy. The development of experimental fuel channel GRK has wide possibility for utilization, from electronic components fast neutron studies, dosimeters testing, to cross section measurements for fast neutron energies. (author)

  8. Reflectivity of the gyroid biophotonic crystals in the ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi.

    Science.gov (United States)

    Michielsen, K; De Raedt, H; Stavenga, D G

    2010-05-06

    We present a comparison of the computer simulation data of gyroid nanostructures with optical measurements (reflectivity spectra and scattering diagrams) of ventral wing scales of the Green Hairstreak butterfly, Callophrys rubi. We demonstrate that the omnidirectional green colour arises from the gyroid cuticular structure grown in the domains of different orientation. We also show that this three-dimensional structure, operating as a biophotonic crystal, gives rise to various polarization effects. We briefly discuss the possible biological utility of the green coloration and polarization effects.

  9. Identification of irradiated foods prospects for post-irradiation estimate of irradiation dose in irradiated dry egg products

    International Nuclear Information System (INIS)

    Katusin-Raxem, B.; Mihaljievic, B.; Razem, D.

    2002-01-01

    Radiation-induced chemical changes in foods are generally very small at the usual processing doses. Some exception is radiation degradation of lipids, which are the components most susceptible to oxidation. A possible use of lipid hydroperoxides (LOOH) as indicators of irradiation is described for whole egg and egg yolk powders. A sensitive and reproducible spectrophotometric method for LOOH measurement based on feric thiocyanate, as modified in our laboratory, was applied. This method enabled the determination of LOOH, including oleic acid hydroperoxides, which is usually not possible with some other frequently used methods. The lowest limit of 0.05 mmol LOOH/kg lipid could be measured. The measurements were performed in various batches of whole egg and egg yolk powders by the same producer, as well as in samples supplied by various producers. Baseline level in unirradiated egg powder 0.110 ± 0.067 mmol LOOH /kgL was established. The formation of LOOH with dose, as well as the influence of age, irradiation conditions, storage time and storage conditions on LOOH were investigated. The irradiation of whole egg and egg yolk powders in the presence of air revealed an initially slow increase of LOOH, caused by an inherent antioxidative capacity, followed by a fast linear increase after the inhibition dose (D o ). In all investigated samples D o of 2 kGy was determined. Hydroperoxides produced in irradiated materials decay with time. In whole egg and egg yolk powders, after an initially fast decay, the level of LOOH continued to decrease by the first-order decay. Nevertheless, after a six months storage it was still possible to unambiguously identify samples which had been irradiated with 2 kGy in the presence of air. Reirradiation of these samples revealed a significant reduction of D o to 1 kGy. In samples irradiated with 4 kGy and kept under the same conditions, the shortening of D o to 0.5 kGy was determined by reirradiation. This offers a possibility for the

  10. Transfer of test samples and wastes between post-irradiation test facilities (FMF, AGF, MMF)

    International Nuclear Information System (INIS)

    Ishida, Yasukazu; Suzuki, Kazuhisa; Ebihara, Hikoe; Matsushima, Yasuyoshi; Kashiwabara, Hidechiyo

    1975-02-01

    Wide review is given on the problems associated with the transfer of test samples and wastes between post-irradiation test facilities, FMF (Fuel Monitoring Facility), AGF (Alpha Gamma Facility), and MMF (Material Monitoring Facility) at the Oarai Engineering Center, PNC. The test facilities are connected with the JOYO plant, an experimental fast reactor being constructed at Oarai. As introductory remarks, some special features of transferring irradiated materials are described. In the second part, problems on the management of nuclear materials and radio isotopes are described item by item. In the third part, the specific materials that are envisaged to be transported between JOYO and the test facilities are listed together with their geometrical shapes, dimensions, etc. In the fourth part, various routes and methods of transportation are explained with many block charts and figures. Brief explanation with lists and drawings is also given to transportation casks and vessels. Finally, some future problems are discussed, such as the prevention of diffusive contamination, ease of decontamination, and the identification of test samples. (Aoki, K.)

  11. Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

    International Nuclear Information System (INIS)

    Akram, Kashif; Ahn, Jae-Jun; Shahbaz, Hafiz Muhammad; Jo, Deokjo; Kwon, Joong-Ho

    2013-01-01

    Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties

  12. Effectiveness of thermoluminescence analysis to detect low quantity of gamma-irradiated component in non-irradiated mushroom powders

    Energy Technology Data Exchange (ETDEWEB)

    Akram, Kashif [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Ahn, Jae-Jun [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Shahbaz, Hafiz Muhammad [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Institute of Food Science and Nutrition, University of Sargodha, Sargodha 40100 (Pakistan); Jo, Deokjo [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Joong-Ho, E-mail: jhkwon@knu.ac.kr [School of Food Science and Biotechnology, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2013-04-15

    Gamma-irradiated (0–10 kGy) dried mushrooms (Lentinus edodes) powders were mixed at different ratios (1–10%) in the non-irradiated samples and investigated using photostimulated-luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) techniques. The PSL results were negative for all samples at 1% mixing ratio, whereas intermediate results were observed for the samples containing 5% or 10% irradiated component with the exception (positive) of 10% mixing of 10 kGy-irradiated sample. The ESR analysis showed the presence of crystalline sugar radicals in the irradiated samples but the radiation-specific spectral features were absent in the mixed samples. TL analysis showed the radiation-specific TL glow curves; however, the complicated results were observed at 1% mixing of 2 and 5 kGy-irradiated samples, which required careful evaluations to draw the final conclusion about the irradiation status of the samples. TL ratios could only confirm the results of samples with 5% and 10% mixing of 10 kGy, and 10% mixing of 5 kGy-irradiated components. SEM-EDX analysis showed that feldspar and quartz were major contaminating minerals, responsible for the radiation-specific luminescence characteristics. -- Highlights: ► Detection of irradiated food is important to enforce the applied regulations. ► The effectiveness of TL analysis was investigated to detect irradiated component. ► The TL results were compared with those from PSL and ESR analysis. ► TL analysis was most effective to characterize the irradiation status of samples. ► SEM-EDX analysis showed feldspar and quartz as the main source of TL properties.

  13. The genetics of green thorax, a new larval colour mutant, non-linked with ruby - eye locus in the malaria mosquito, Anopheles stephensi.

    Science.gov (United States)

    Sanil, D; Shetty, N J

    2009-06-01

    Anopheles stephensi, an important vector of malaria continues to be distributed widely in the Indian subcontinent. The natural vigour of the species combined with its new tolerance, indeed resistance to insecticides has made it obligatory that we look for control methods involving genetic manipulation. Hence, there is an immediate need for greater understanding of the genetics of this vector species. One of the requirements for such genetic studies is the establishment of naturally occurring mutants, establishment of the genetic basis for the same and use of such mutants in the genetic transformation studies and other genetic control programme(s). This paper describes the isolation and genetic studies of a larval colour mutant, green thorax (gt), and linkage studies involving another autosomal recessive mutant ruby- eye (ru) in An. stephensi. After the initial discovery, the mutant green thorax was crossed inter se and pure homozygous stock of the mutant was established. The stock of the mutant ruby- eye, which has been maintained as a pure stock in the laboratory. Crosses were made between the wild type and mutant, green thorax to determine the mode of inheritance of green thorax. For linkage studies, crosses were made between the mutant green thorax and another autosomal recessive mutant ruby-eye. The percentage cross-over was calculated for the genes linkage relationship for gt and gt ru. Results of crosses between mutant and wild type showed that the inheritance of green thorax (gt) in An. stephensi is monofactorial in nature. The gt allele is recessive to wild type and is autosomal. The linkage studies showed no linkage between ru and gt. The mutant gt represents an excellent marker for An. stephensi as it is expressed in late III instar stage of larvae and is prominent in IV instar and pupal stages with complete penetrance and high viability. The said mutant could be easily identified without the aid of a microscope. This mutant can be used extensively to

  14. Measuring the critical current in superconducting samples made of NT-50 under pulse irradiation by high-energy particles

    International Nuclear Information System (INIS)

    Vasilev, P.G.; Vladimirova, N.M.; Volkov, V.I.; Goncharov, I.N.; Zajtsev, L.N.; Zel'dich, B.D.; Ivanov, V.I.; Kleshchenko, E.D.; Khvostov, V.B.

    1981-01-01

    The results of tests of superconducting samples of an uninsulated wire of the 0.5 mm diameter, containing 1045 superconducting filaments of the 10 μm diameter made of NT-50 superconductor in a copper matrix, are given. The upper part of the sample (''closed'') is placed between two glass-cloth-base laminate plates of the 50 mm length, and the lower part (''open'') of the 45 mm length is immerged into liquid helium. The sample is located perpendicular to the magnetic field of a superconducting solenoid and it is irradiated by charged particle beams at the energy of several GeV. The measurement results of permissible energy release in the sample depending on subcriticality (I/Isub(c) where I is an operating current through the sample, and Isub(c) is a critical current for lack of the beam) and the particle flux density, as well as of the maximum permissible fluence depending on subcriticality. In case of the ''closed'' sample irradiated by short pulses (approximately 1 ms) for I/Isub(c) [ru

  15. Bakery products from irradiated and non-irradiated eggs - analytical problems associated with the detection of irradiation in processed foods

    International Nuclear Information System (INIS)

    Grabowski, H.U. von; Pfordt, J.

    1993-01-01

    In spring and early summer 1992, a number of irradiated egg products were illegally imported into Germay. To prove the irradiation of these egg products, mainly combined gas chromatography-mass spectrometry was applied. With this present study we wanted to answer the question if we were also able to detect the use of irradiated eggs in processed foods. The processed food we chose to produce and to investigate was a tart layer. For this product, dilution effects are of minor importance as no extra fat was added. Thus, the layers' fat almost exclusively came from the eggs. To study the influence of emulsifiers, we produced batters both with and without adding an emulsifer. The unsaturted hydrocarbons C14:1, C16:3, C16:2, C17:2, and C17:1 served as markers for an irradiation. In the non-irradiated egg samples and in the tart layers produced from them, these compounds could not be detected (or in some cases only in small amounts). They were, however, detectable in all irradiated samples. DCB could be found in all irradiated egg samples and in the tart layers that were baked from irradiated eggs. It was not present in non-irradiated eggs and in tart layers produced from them. (orig./Vhe)

  16. Delayed match-to-sample early performance decrement in monkeys after 60Co irradiation

    International Nuclear Information System (INIS)

    Bruner, A.; Bogo, V.; Jones, R.K.

    1975-01-01

    Sixteen monkeys were trained on a delayed match-to-sample task (DMTS) based on shock avoidance and irradiated with single, whole-body exposures of from 396 to 2000 rad 60 Co (midbody dose) at between 163 and 233 rad/min. Pre- to post-irradiation performance changes were assessed using a penalty-scaling measure which differentially weighted incorrect responses, response omissions, and error-omission sequences. Thirteen of the animals displayed early performance decrement, including five incapacitations, at lower doses (less than 1000 rad) than heretofore found effective. This was considered a function of task complexity, measurement sensitivity, and gamma effectiveness. The minimum effective midbody dose for inducing decrement using the DMTS task was estimated to be on the order of 500 rad. The nature of early, transient performance decrement seems to reflect more of an inability to perform than an inability to perform correctly

  17. Progress on using deuteron-deuteron fusion generated neutrons for 40Ar/39Ar sample irradiation

    Science.gov (United States)

    Rutte, Daniel; Renne, Paul R.; Becker, Tim; Waltz, Cory; Ayllon Unzueta, Mauricio; Zimmerman, Susan; Hidy, Alan; Finkel, Robert; Bauer, Joseph D.; Bernstein, Lee; van Bibber, Karl

    2017-04-01

    We present progress on the development and proof of concept of a deuteron-deuteron fusion based neutron generator for 40Ar/39Ar sample irradiation. Irradiation with deuteron-deuteron fusion neutrons is anticipated to reduce Ar recoil and Ar production from interfering reactions. This will allow dating of smaller grains and increase accuracy and precision of the method. The instrument currently achieves neutron fluxes of ˜9×107 cm-2s-1 as determined by irradiation of indium foils and use of the activation reaction 115In(n,n')115mIn. Multiple foils and simulations were used to determine flux gradients in the sample chamber. A first experiment quantifying the loss of 39Ar is underway and will likely be available at the time of the presentation of this abstract. In ancillary experiments via irradiation of K salts and subsequent mass spectrometric analysis we determined the cross-sections of the 39K(n,p)39Ar reaction at ˜2.8 MeV to be 160 ± 35 mb (1σ). This result is in good agreement with bracketing cross-section data of ˜96 mb at ˜2.45 MeV and ˜270 mb at ˜4 MeV [Johnson et al., 1967; Dixon and Aitken, 1961 and Bass et al. 1964]. Our data disfavor a much lower value of ˜45 mb at 2.59 MeV [Lindström & Neuer, 1958]. In another ancillary experiment the cross section for 39K(n,α)36Cl at ˜2.8 MeV was determined as 11.7 ± 0.5 mb (1σ), which is significant for 40Ar/39Ar geochronology due to subsequent decay to 36Ar as well as for the determination of production rates of cosmogenic 36Cl. Additional experiments resolving the cross section functions on 39K between 1.5 and 3.6 MeV are on their way using the LICORNE neutron source of the IPN Orsay tandem accelerator. Results will likely be available at the time of the presentation of this abstract. While the neutron generator is designed for fluxes of ˜109 cm-2s-1, arcing in the sample chamber currently limits the power—straightforwardly correlated to the neutron flux—the generator can safely be run at. Further

  18. Microstructural study of Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x}/Ag samples irradiated with {sup 60}Co {gamma} rays at high doses

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, R [Programa de Postgrado en Fisica de Materiales, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Galvan, D H [CECIMAC-UNAM, Apartado Postal 2681, CP 22800, Ensenada, BC (Mexico); Adem, E [Instituto de Fisica-UNAM, Apartado Postal 20-364, CP 01000, Mexico DF (Mexico); Bartolo-Perez, P [CINVESTAV-IPN Unidad Merida, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Maple, M B [Physics Department and Institute for Pure and Applied Physical Sciences, La Jolla, CA (United States)

    1998-06-01

    We have investigated the damage induced by irradiation in Y{sub 1}Ba{sub 2}Cu{sub 3}O{sub 7-x} silver added samples. The samples were prepared with 0 and 6.5 wt% of silver and irradiated by high-energy {gamma} irradiation (50-150 Mrad). The roles of silver and dosage irradiation are discussed in terms of their effects on microstructure, crystallinity, critical temperature (T{sub c}) and zero-resistance temperature (T{sub 0}). After irradiation, T{sub c} decreased while the room-temperature electrical resistance increased by a factor of 8 for some of the samples. The difference in T{sub 0} between irradiated and non-irradiated YBCO samples was of the order of 10 K. We have found that the difference is bigger for silver-added samples. We have also observed several changes in diffraction patterns of YBCO and YBCO-silver samples. SEM images, EDS and XPS analysis showed that silver resided inside the grains as single atoms and as metallic clusters. The relative concentrations of the elements in samples were quantified by Auger electron spectroscopy. The values showed a gradual increase for radiation doses ranging between 0 and 100 Mrad. For doses up to 100 Mrad, J{sub c} decreased because of the weak-link breakage induced by high doses of {gamma} rays. (author)

  19. Comparison in electron density distribution of tokamak plasma between ruby-laser scattering and milli-meter wave interferometric measurements

    International Nuclear Information System (INIS)

    Matoba, Tohru; Funahashi, Akimasa; Itagaki, Tokiyoshi; Takahashi, Koki; Kumagai, Katsuaki

    1976-08-01

    The electron density in JFT-2 tokamak has been measured by two methods, i.e. Thomson scattering of ruby-laser light and interferometry of millimeter wave. Two-dimensional distribution of the scattered light intensities were obtained by scattering measurement; absolute calibration was made by normalizing the scattered intensities with the averaged density determined from interferometric measurement. The horizontal density distributions in laser scattering were compared with those in from the averaged densities measured with a 4-mm interferometer through inverse-transformation. Agreement is good between the two measurements, except where they give erroneous data because of irreproducibility of the discharge. (auth.)

  20. Dosimetry of blood irradiator - 2000

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.; Shinde, S.H.; Bhat, R.M.; Rao, Suresh; Sharma, D.N.

    2008-01-01

    Full text: Blood transfusion to an immunodeficient or immunosuppressed patient has a high risk involved due to occurrence of Transfusion Graft Versus Host Disease (T-GVHD). In order to eliminate this problem, blood is routinely exposed to ionizing radiation (gamma) prior to transfusion. Doses ranging from 15 Gy to 50 Gy can prevent T-GVHD. Aim of the present work was to perform dosimetry of 60 Co Blood Irradiator-2000 developed by Board of Radiation and isotope Technology (BRIT), India; using FBX dosimetric system. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which is a Reference Standard dosimeter. Experiments included measurement of dose-rate at the centre of irradiation volume, dose mapping in the central vertical plane within the irradiation volume and measurement of average dose received by blood sample using blood bags filled with FBX dosimeter by simulating actual irradiation conditions. During irradiation, the sample chamber is retracted into a cylindrical source cage, so that the sample is irradiated from all sides uniformly. Blood irradiator-2000 has sample rotation facility for increasing the dose uniformity during irradiation. The performance of this was investigated by measuring the central vertical plane dose profile in stationary state as well in rotation using the sample rotation facility (60 rpm). FBX being an aqueous dosimetric system fills container of irregular shape being irradiated hence can be used to integrate the dose over the volume. Dose-rate measured by FBX dosimeter was intercompared with Fricke dosimeter, which was in good agreement. Average dose-rate at the centre of irradiation volume and within the blood bag was measured by FBX and Fricke dosimeters. It was observed that dose profiles measured by FBX and Fricke dosimeters agreed within ± 2%. Dose uniformity within the irradiation volume was found to reduce from 21% to 17% when the sample rotation facility was used. Thus, it is suggested by the

  1. Late summer disease symptoms in western Washington red raspberry fields associated with co-occurrence of Phytophthora rubi, Verticillium dahliae, and Pratylenchus penetrans, but not Raspberry bushy dwarf virus

    Science.gov (United States)

    60% of the $109 million processed by the U.S. red raspberry industry is in northern Washington. In 2012, late summer disease symptoms were observed in many raspberry fields. These symptoms were initially attributed to Verticillium dahliae, but other soilborne pathogens (Phytophthora rubi, Pratylench...

  2. Differential-thermal analysis of irradiated lignite

    International Nuclear Information System (INIS)

    Chichek, F; Eyubova, N.

    2006-01-01

    Full text: In this theme our purpose is to explain thermo-differential analysis of lignite's irradiated. During experiment Caraman Ermenek (washed), Caraman Ermenek (crude), Nevshehir (crude), Slopi (crude), Trakya Harman (washed) lignite coals were used. Five of five kinds of coal samples with 3mm and 1 gr of each sample were obtained. Then they were filled into the Tubes after having dried total 25 samples with 1 gr at 1000C temperature for one hour. Air in the tubes was pumped out and closed. Coal samples in vacuum medium were irradiated by gamma rays of Co-60 at 5.5 kGy, 19.2 kGy, 65.7 kGy, 169.6 kGy, 411.2 kGy, doses to the normal conditions. At the end coal irradiated samples were compared with original coal samples. At the result of experiment it was revealed that in comparison with original coal samples coal samples irradiated from exothermic and endothermic curves at very reaction pick and temperature intervals of these pick were large. Besides loss of weight was observed to begin at low temperatures in samples irradiated and especially momentary weight loss at some heats in the rang of known temperatures was observed in the coal Slopi contain in bitumen. Because of heat the weight loss in the non irradiated samples forms parabolic curve and because of heat the weight loss in the samples irradiated forms stepped curves. It was shown that the coal irradiated can be easily departed by heat because of the chemical structure in comparison the original one.

  3. 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

  4. Antibacterial activity of irradiated and non-irradiated chitosan and chitosan derivatives against Escherichia coli growth

    International Nuclear Information System (INIS)

    Tg Ahbrizal Farizal Tg Ahmad; Norimah Yusof; Kamarudin Bahari; Kamaruddin Hashim

    2006-01-01

    Samples of chitosan and four chitosan derivatives [ionic chitosan, chitosan lactate, carboxymethyl chitosan (C) and carboxymethyl chitosan (L)] were studied for their antibacterial activities against Escherichia coli growth. Chitosan and chitosan derivatives were prepared at concentrations 20, 100, 1000, 10000 ppm and 250, 1000, 5000, 10000, 20000 ppm, respectively. Each of the samples was tested before and after irradiation with electron beam at 25 kGy. The turbidity of bacterial growth media was measured periodically at 0, 0.5, 1, 2, 4, 6 and 24 h after inoculation using the optical density method. The results indicated that non- irradiated chitosan inhibited E. coli growth at 20 and 100 ppm. Meanwhile, irradiated chitosan at 100 and 1000 ppm concentration inhibited E. coli growth. Both irradiated and non-irradiated ionic chitosan inhibited E. coli growth at all concentrations used. Chitosan lactate was found to inhibit E. coli at concentration as low as 5000 ppm for both irradiated and non-irradiated samples. E. coli growth was not inhibited by carboxymethyl chitosan (C) and carboxymethyl chitosan (L), before and after irradiation. The findings suggested that chitosan has greater antibacterial activity as compared to the chitosan derivative samples. (Author)

  5. Bovine manure doses for agronomic and fiber characteristics of the BRS Rubi upland cotton = Doses de esterco bovino nas características agronômicas e de fibras do algodoeiro herbáceo BRS Rubi.

    Directory of Open Access Journals (Sweden)

    José Rodrigues Pereira

    2012-12-01

    Full Text Available In Paraíba, Brazil, a local market for family farming is the production of naturally colored cotton grown in agroecological regime. For solution of physicochemical and biological soil degradation of brazilian semiarid, where Caatinga biome predominates, one valuable agroecological practice is the organic adubation. Accordingly, it was aimed with the present work to study the influence of bovine manure doses (D0 - 0.0; D1 - 2.5; D2 - 5.0; D3 - 10.0; D4 - D5 and 20.0 - 40.0 Mg ha-1 on agronomic and fiber characteristics of the agroecological herbaceous cotton BRS Rubi crop in the arid region of that State, in the years 2008/2009 and 2009, and to define the best dose of this organic fertilizer for this system and this growing region. The treatments were arranged in a randomized block design, with four replications. It was performed combined analysisof variance of the experiments, being evaluated agronomic (stem diameter, plant height, yeild and boll weight and fiber(percentage, length, strength, micronaire index, fiber short index, elongation and maturity of fibers variables in the two yearsof cultivation. It was concluded that: there was influence of the bovine manure doses tested for the agronomic characteristicsbut not for the characteristics of the fibers of the herbaceous cotton colored BRS Rubi; the best dose was 18 Mg ha-1of bovinemanure (Maximum Economic Dose. = Na Paraíba, um nicho de mercado para a agricultura familiar é a produção de algodão naturalmente colorido ecultivado agroecologicamente. Para solução da degradação físico-química e biológica dos solos do semiárido brasileiro, onde o bioma caatinga predomina, uma prática agroecológica valiosa é a adubação orgânica. Nesse sentido, objetivou-se com o presente trabalho estudar a influência de doses de esterco bovino (D0 - 0; D1 - 2,5; D2 - 5; D3 - 10; D4 - 20 e D5 - 40 Mg ha-1 sobre características agronômicas e da fibra do algodoeiro herbáceo colorido BRS Rubi

  6. New experimental space for irradiating samples by RA reactor fast neutron flux at temperatures up to 100 deg C

    International Nuclear Information System (INIS)

    Pavicevic, M.; Novakovic, M.; Zecevic, V.

    1961-01-01

    The objective of this paper is to present adaptation of the RA reactor which would enable samples irradiation by fast neutrons and describe new experimental possibilities. New experimental space was achieved using hollow fuel elements which have been reconstructed to enable placement of irradiation capsules inside the tube. This paper includes thermal analysis and describes problems related to operation, safety and radiation protection issues which arise from using reconstructed fuel elements

  7. Pulsed Q-switched ruby laser annealing of Bi implanted Si crystals investigated by channeling

    International Nuclear Information System (INIS)

    Deutch, B.I.; Shih-Chang, T.; Shang-Hwai, L.; Zu-Yao, Z.; Jia-Zeng, H.; Ren-Zhi, D.; Te-Chang, C.; De-Xin, C.

    1979-01-01

    Channeling was used to investigate pulsed, Q switched ruby-laser annealed and thermally annealed Si single crystals implanted with 40-keV Bi ions to a dose of 10 15 atoms/cm 2 . After thermal annealing, residual damage decreased with increasing annealing temperature to a minimum value of 30% at 900 0 C. The Bi atoms in substitutional sites reached a maximum value (50%) after annealing at 750 0 C but decreased with increasing annealing temperature. Out diffusion of Bi atoms occurred at temperatures higher than 625 0 C. For comparison, the residual damage disappeared almost completely after pulsed-laser annealing (30 ns pulse width, Energy, E = 3J/cm 2 ). The concentration of Bi in Si exceeded its solid solubility by an order of magnitude; 95% of Bi atoms were annealed to substitutional sites. Laser pulses of different energies were used to investigate the efficiency of annealing. (author)

  8. Thermal analysis of the APT materials irradiation samples

    International Nuclear Information System (INIS)

    Maloy, S.A.; Willcutt, G.J.; James, M.R.; Teague, J.; Diebe, D.A.; Sommer, W.F.; Ferguson, P.D.

    1998-01-01

    The accelerator production of tritium (APT) project proposes to use a 1.7 GeV, 100 mA proton beam to produce neutrons from an Inconel 718 clad tungsten target. The neutrons are multiplied and moderated in a lead/water blanket before being captured in He 3 to form tritium. In this process, the materials in the target and blanket region are exposed to a wide range of different fluxes comprised of protons and neutrons with energies into the GeV range. To investigate the effect of irradiation on the mechanical properties of candidate APT materials (Inconel 718, 316L stainless steel, Al 6061-T6, Mod 9Cr-1Mo, 304L stainless steel and Al5052-0), the APT Engineering Design and Development group fielded an extensive materials irradiation using the LANSCE (Los Alamos Neutron Science Center) accelerator, which operates at an energy of 800 MeV and a current of 1 mA. The test set-up was designed to place mechanical test specimens in locations in and near the proton beam where the environment of proton and neutron fluxes and temperatures are prototypic to those expected in the APT target/blanket (50--170 C). After irradiating for about 3,600 hours, the maximum achieved proton fluence was 4--5 x 10 21 p/cm 2 for the materials in the center of the beam. To obtain relevant data on the change in the mechanical properties with fluence, it is essential to know the temperature at which the materials were irradiated. This paper explains the method of determining the specimen temperature and reports some specific examples

  9. Irradiation enhanced diffusion and irradiation creep tests in stainless steel alloys

    International Nuclear Information System (INIS)

    Loelgen, R.H.; Cundy, M.R.; Schuele, W.

    1977-01-01

    A review is given of investigations on the rate of phase changes during neutron and electron irradiation in many different fcc alloys showing either precipitation or ordering. The diffusion rate was determined as a function of the irradiation flux, the irradiation temperature and the irradiation dose. It was found that the radiation enhanced diffusion in all the investigated alloys is nearly temperature independent and linearly dependent on the flux. From these results conclusions were drawn concerning the properties of point defects and diffusion mechanisms rate determining during irradiation, which appears to be of a common nature for fcc alloys having a similar structure to those investigated. It has been recognized that the same dependencies which are found for the diffusion rate were also observed for the irradiation creep rate in stainless steels, as reported in literature. On the basis of this observation a combination of measurements is suggested, of radiation enhanced diffusion and radiation enhanced creep in stainless steel alloys. The diffusion tests will be performed at the Euratom Joint Research Centre in Ispra, Italy, and the irradiation creep tests will be carried out in the High Flux Reactor /9/ of the Euratom Joint Research Centre in Petten, The Netherlands. In order to investigate irradiation creep on many samples at a time two special rigs were developed which are distinguished only by the mode of stress applied to the steel specimens. In the first type of rig about 50 samples can be tested uniaxially under tension with various combinations of irradiation temperature and stress. The second type of rig holds up to 70 samples which are tested in bending, again with various combinations of irradiation temperature and stress

  10. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    International Nuclear Information System (INIS)

    Rapp, Juergen; Aaron, A. M.; Bell, Gary L.; Burgess, Thomas W.; Ellis, Ronald James; Giuliano, D.; Howard, R.; Kiggans, James O.; Lessard, Timothy L.; Ohriner, Evan Keith; Perkins, Dale E.; Varma, Venugopal Koikal

    2015-01-01

    5-20 MW/m"2 and ion fluxes up to 10"2"4 m"-"2s"-"1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

  11. Mechanical and irradiation properties of zirconium alloys irradiated in HANARO

    International Nuclear Information System (INIS)

    Kwon, Oh Hyun; Eom, Kyong Bo; Kim, Jae Ik; Suh, Jung Min; Jeon, Kyeong Lak

    2011-01-01

    These experimental studies are carried out to build a database for analyzing fuel performance in nuclear power plants. In particular, this study focuses on the mechanical and irradiation properties of three kinds of zirconium alloy (Alloy A, Alloy B and Alloy C) irradiated in the HANARO (High-flux Advanced Neutron Application Reactor), one of the leading multipurpose research reactors in the world. Yield strength and ultimate tensile strength were measured to determine the mechanical properties before and after irradiation, while irradiation growth was measured for the irradiation properties. The samples for irradiation testing are classified by texture. For the irradiation condition, all samples were wrapped into the capsule (07M-13N) and irradiated in the HANARO for about 100 days (E > 1.0 MeV, 1.1 10 21 n/cm 2 ). These tests and results indicate that the mechanical properties of zirconium alloys are similar whether unirradiated or irradiated. Alloy B has shown the highest yield strength and tensile strength properties compared to other alloys in irradiated condition. Even though each of the zirconium alloys has a different alloying content, this content does not seem to affect the mechanical properties under an unirradiated condition and low fluence. And all the alloys have shown the tendency to increase in yield strength and ultimate tensile strength. Transverse specimens of each of the zirconium alloys have a slightly lower irradiation growth tendency than longitudinal specimens. However, for clear analysis of texture effects, further testing under higher irradiation conditions is needed

  12. Generation of electromagnetic radiation in laser action with solids

    International Nuclear Information System (INIS)

    Aref'ev, K.P.; Vorob'ev, S.A.; Kuznetsov, M.F.; Mastov, Sh.R.; Pogrebnyak, A.D.

    1984-01-01

    A new effect of electromagnetic pulse generation in solids, exposed to laser irradiation was revealed experimentally. The ruby laser with 694.36 nm wave length was used in the experiments. Monocrystals of Si, GaAs, KCl, LiF, polycrystals of Cu, Al, metals, the rocks-calcite, marble, natural quartz, feldspar - were used as samples. The effect of electromagnetic pulse generation, which is characterized by sharp threshold dependence on the density of laser radiation power, as well as on the type of material and its characteristics was observed for each material. The possibility of using the method of electromagnetic pulse detection during laser irradiation for evaluation of defectiveness degree and strength characteristics of investigated materials was shown

  13. 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

  14. Hemangioma rubi no couro cabeludo Cherry hemangioma in the scalp

    Directory of Open Access Journals (Sweden)

    José Marcos Pereira

    2004-02-01

    Full Text Available O hemangioma rubi (HR é dermatose de origem vascular extremamente freqüente, acometendo mais de 75% da população acima de 70 anos de idade. Em geral compõe-se de lesões múltiplas,localizadas predominantemente no alto do tronco e braços. Clinicamente é caracterizado por lesões que variam desde máculas puntiformes até lesões papulosas com cinco milímetros de diâmetro. As mais novas são vermelhas, em tons vivos, e as mais antigas podem ser azuladas. O HR é de etiologia desconhecida. Histologicamente chama atenção uma neoformação de vasos capilares, que se tornam dilatados e com fenestrações em suas paredes. A membrana basal está muito espessada e existe abundante estroma de colágeno entre os vasos. O presente trabalho demonstra a alta incidência do HR no couro cabeludo Em amostra de 171 pacientes, sendo 85 homens e 86 mulheres, o autor observou que 123 deles (72% tinham HR no couro cabeludo, localização em que o HR nunca foi descrito na literatura.Cherry hemangioma (CH is an extremely frequent dermatosis with vascular origin involving more than 75% of the population over 70 years of age. Normally they are multiplex spots and focus predominantly on the upper trunk and arms. Clinically they are characterized by pinpoint maculae and papules with up to 5 millimeters in diameter. The most recent lesions can be a strong red color while the older ones are bluish. The etiology of CH is still unknown. From the histologic standpoint, the neoformation of the capillary tube draws attention: they are very dilated and with fenestration along the wall. The basement membranes are thickened and there is abundant collagen stroma between the veins. This work demonstrates the high frequency of CH in the scalp. In a sample of 171 patients (85 men and 86 women the author noted that 123 (72% had CH in the scalp. However, according to the literature, CH in the scalp has never been described.

  15. Comet assay in the detection of irradiated garlic

    International Nuclear Information System (INIS)

    Villavicencio, Anna Lucia C.H.; Marin-Huachaca, Nelida Simona; Romanelli, Maria Fernanda; Delincee, Henry

    2002-01-01

    The increased claim for fresh produce has forced a consensus between nations to pay more attention to the phytosanitary regulations. Inhibition of sprouting of bulbs and tubers by applying ionising radiation is authorised by the National Food Codes in Brazil. The availability of methods for detection of irradiated food will contribute to increase consumers' confidence. A quick and simple screening test to indicate whether a food product has been irradiated or not was utilised in this study. The DNA comet assay was applied to verify whether garlic imported from China had been irradiated or not. This test has already been adopted as a European Standard (EN 13784), for detection of irradiated food. Non-irradiated control samples of garlic and garlic treated with maleic hydrazide were compared with garlic samples irradiated in our department. The unirradiated samples exhibited only limited DNA migration. If samples were irradiated, an increased DNA fragmentation was observed which permitted the discrimination between non-irradiated and irradiated samples. Since the garlic samples from China showed only very limited DNA fragmentation, they were deemed non-irradiated. Thus, this simple screening test was shown to be successful for identification of an irradiation treatment. (author)

  16. HRB-22 capsule irradiation test for HTGR fuel. JAERI/USDOE collaborative irradiation test

    Energy Technology Data Exchange (ETDEWEB)

    Minato, Kazuo; Sawa, Kazuhiro; Fukuda, Kousaku [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; and others

    1998-03-01

    As a JAERI/USDOE collaborative irradiation test for high-temperature gas-cooled reactor fuel, JAERI fuel compacts were irradiated in the HRB-22 irradiation capsule in the High Flux Isotope Reactor at the Oak Ridge National Laboratory (ORNL). Postirradiation examinations also were performed at ORNL. This report describes 1) the preirradiation characterization of the irradiation samples of annular-shaped fuel compacts containing the Triso-coated fuel particles, 2) the irradiation conditions and fission gas releases during the irradiation to measure the performance of the coated particle fuel, 3) the postirradiation examinations of the disassembled capsule involving visual inspection, metrology, ceramography and gamma-ray spectrometry of the samples, and 4) the accident condition tests on the irradiated fuels at 1600 to 1800degC to obtain information about fuel performance and fission product release behavior under accident conditions. (author)

  17. Comparative study of thermoluminescence detection methods for irradiated spices

    International Nuclear Information System (INIS)

    Kawamura, Y.; Kojima, K.; Sugita, T.; Yamada, T.; Saito, Y.

    1995-01-01

    The thermoluminescence (TL) detection methods for irradiated spices were compared using spice samples obtained on the Japanese market, irradiated at doses of 1, 5, 10 and 30 kGy and stored for 1 year before analysis. The TL intensities of irradiated spices were stable for 1 year after irradiation. Measurement with whole samples failed to identify irradiated samples. Minerals were separated from spices in sodium tungstate saturated solution and/or sodium polytungstate solution. The TL intensity of minerals which had undergone irradiation was significantly increased for all samples. However, the ranges of TL intensity of irradiated and unirradiated samples overlapped. Clear discrimination has been obtained between the TL ratios of irradiated and unirradiated spices by using normalized measurement with reirradiation. The detection limit in terms of irradiation dose is 1 kGy even in a sample that has been irradiated 1 year prior to analysis. Normalization is the best technique currently available for thermoluminescence analysis to identify irradiated spices

  18. Detection of irradiated strawberries by identifying ESR peak of irradiated cellulose component

    International Nuclear Information System (INIS)

    Goto, Michiko; Tanabe, Hiroko

    2002-01-01

    The method of detecting low-dose irradiated strawberries by identifying ESR peak of irradiated cellulose component was studied. Ratio of peak height (S) of high magnetic field cellulose component, and noise width (N) of either irradiated or unirradiated seeds of strawberries were compared. In this study, sample was identified to be irradiated when S/N ratio of ESR spectrum of 4 min. sweep time was above 0.7. In the case of S/N ratio below 0.7, when the S/N ratio of integrated ESR spectrum, obtained from measuring 10 times with 1 min. sweep time was above 1.0, the sample was identified to be irradiated. The result suggests that S/N ratio is a good marker to detect the irradiation. The strawberries irradiated above 0.5kGy was able to be detected after 3 days storage at room temperature, after 21 days refrigeration and after 60 days freezing, respectively. (author)

  19. Irradiation of meat products, chicken and use of irradiated spices for sausages

    Science.gov (United States)

    Kiss, I. F.; Beczner, J.; Zachariev, Gy.; Kovács, S.

    The shelf-life of packed minced meat has been increased at least threefold at 4°C by applying a 2 kGy dose. Results have been confirmed by detailed quatitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated samples. The optimal average dose was 4 kGy for packed-frosen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterbacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. In sensory evaluations there was no significant difference between untreated and irradiated samples. In 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices.

  20. Physicochemical and sensory properties of irradiated dry-cured ham

    International Nuclear Information System (INIS)

    Jin, Sang-Keun; Kim, Chul-Wook; Chung, Ki-Hwa; Jo, Kwang-Keun; Jeong, Jin-Yeon; Hur, In-Chul; Jung, Eun-Young; Joo, Seon-Tea; Yang, Han-Sul

    2012-01-01

    To determine the effect of different irradiation doses on ready-to-eat (RTE) dry-cured shoulder hams, physicochemical and sensory attributes were analyzed during 8 weeks of refrigerated storage. The results show that irradiation reduced the redness value and increased the 2-thiobarbituric acid-reactive substance (TBARS) value as well as the irradiation aroma during storage. However, ham samples irradiated with 2.5 and 5.0 kGy did not show significant changes in lightness values compared to the control sample during 8 weeks of storage. TBARS values were lower in the sample irradiated with 2.5 kGy than in the other irradiated samples. The total plate counts of the 5.0 kGy-irradiated samples were not measured after 0 weeks. Sensory panels found that the 2.5- and 5.0 kGy-irradiated samples had better overall acceptability scores than the other irradiated samples. It was concluded that treatments with lower levels of irradiation (≤5.0 kGy) can enhance the microbial safety and sensory acceptance of dry-cured shoulder hams. - Highlights: ► Effect of different irradiation doses on quality properties of dry-cured hams. ► The 2.5 kGy irradiated sample did not show any changes in lipid oxidation. ► Irradiation at 5.0 kGy has the potential to greatly decrease the TPC. ► Low-dose irradiation can improve the microbial safety and maintain the sensory acceptance.

  1. Shipboard-irradiation of haddock

    International Nuclear Information System (INIS)

    Ehlermann, D.; Reinacher, E.; Antonacopoulos, N.

    1977-01-01

    Haddock caught during the 183rd and 185th voyage of the RV 'Anton Dohrn' off Faeroeer was gutted, washed and packed under vacuum in polyethylene pouches. The samples were irradiated with the onboard X-ray source. During one series of experiments a minimum dose of 65 krad and a maximum dose of 130 krad was used. During further series the minimal dose was set to 100 krad, resulting in maximum values of 140 krad and 180 krad. As judged by taste panel evaluation of steam-cooked, unseasoned filets, quality preservation of all samples during the first 16 days of iced storage did not depend on irradiation. After that period the fish had lost prime quality. At this time, irradiated samples were rated slightly better than unirradiated ones. Base on our results, the shipboard-irradiation of prepacked haddock cannot be recommended. This does not exclude that under different conditions (e.g. fishfilets in retail packages) beneficial effects of irradiation may be observed. (orig.) [de

  2. Shipboard-irradiation of haddock

    International Nuclear Information System (INIS)

    Ehlermann, D.; Reinacher, E.; Antonacopoulos, N.

    1977-01-01

    Haddock caught during the 183rd and 185th voyage of the RV 'Anton Dohrn' off Faeroer was gutted, washed and packed under vacuum in polythylene pouches. The samples were irradiated with the onboard X-ray source. During one series of experiments a minimum dose of 65 krad and a maximum dose of 130 krad was used. During further series the minimal dose was set to 100 krad, resulting in maximum values of 140 krad and 180 krad. As judged by taste panel evalution of steam-cooked, unseasoned filets, quality preservation of all samples during the first 16 days of iced storage did not depend on irradiation. After that period the fish had lost prime quality. At this time, irradiated samples were rated slightly better than unirradiated ones. On the basis of these results, the shipboard-irradiation of prepacked haddock cannot be recommended. This does not exclude that under different conditions (e.g. fishfilets in retail packages) beneficial effects of irradiation may be observed. (orig.) [de

  3. Differential-thermal analysis of irradiated lignite

    International Nuclear Information System (INIS)

    Chichek, F.; Eyubova, N.

    2006-01-01

    Full text: In this theme our purpose is to explain thermo-differential analysis of lignites irradiated. During experiment Caraman Ermenek (washed), Caraman Ermenek (crude), Nevshehir (crude), Slopi (crude), Trakya Harman (washed) lignite coals were used. Five of five kinds of coal samples with 3mm and 1gr of each sample were obtained. Then they were filled into the Tubes after having dried total 25 samples with 1 gr at 1000 degrees temperature for one hour. Air in the tubes was pumped out and closed. Coal samples in vacuum medium were irradiated by gamma rays of Co60 at 5.5 kGy, 19.2 kGy, 65.7 kGy, 169.6 kGy, 411.2 kGy doses to the normal conditions. Then differential thermal analysis was carried out both in original and the samples irradiated. Argon gas was used to make inert medium in the camera. T=200-8500 degrees temperature was selected. At the experiment done from 1000-1300 degrees temperatures too great endothermic reaction pick was begun to form by being observed thermal changings. At 3000-4200 degrees temperature exothermic reaction picks and at 7000 degrees parallel exothermic reaction picks were observed. Initial endothermic and exothermic reaction picks in five lignite samples were observed like a sharp curve. At the end coal irradiated samples were compared with original coal samples. At the result of experiment it was revealed that in comparison with original coal samples coal samples irradiated form exothermic and endothermic curves at very reaction pick and temperature intervals of these pick were large. Besides loss of weight was observed to begin at low temperatures in samples irradiated and especially momentary weight loss at some heats in the rang of known temperatures was observed in the coal Slopi contain in bitumen. Because of heat the weigh loss in the non irradiated samples forms parabolic curve and because of heat the weight loss in the samples irradiated forms stepped curves. It has shown that the coal irradiated can be easily departed by

  4. Sensorial evaluation of irradiated mangoes

    International Nuclear Information System (INIS)

    Broisler, Paula Olhe; Cruz, Juliana Nunes da; Sabato, Susy Frey

    2007-01-01

    Mango (Mangifera indica L.) is a tropical fruit of great economical relevance in the world, mainly for tropical countries like Brazil. It consists in the second tropical fruit more important grown in the world. On the other hand it is a very perishable fruit and its delivery to distant points is restricted due to short shelf life at environmental temperature. Food irradiation process is applied to fruits for their preservation, once it promotes disinfestation and even maturation retard, among other mechanisms. The Brazilian legislation permits the food irradiation and does not restrict the doses to be delivered. In order to verify eventual changes, sensorial evaluation is very important to study how irradiation affects the quality of the fruit and its acceptability. Mangoes were irradiated in a Cobalto-60 source, from the Radiation Technology Center, CTR, of IPEN/CNEN-SP at doses 0,5 kGy e 0,75 kGy. The sensorial evaluation was measured through Acceptance Test where irradiated samples were offered together with control sample to the tasters who answered their perception through hedonic scale. The parameters Color, Odor, Flavor and Texture were analyzed. Statistical analysis showed that only Odor parameter was different from control (sample irradiated at 0.5 kGy). Few tasters indicated that irradiated mangoes had fewer odors in relation to non-irradiated samples. (author)

  5. Sensorial evaluation of irradiated mangoes

    Energy Technology Data Exchange (ETDEWEB)

    Broisler, Paula Olhe; Cruz, Juliana Nunes da; Sabato, Susy Frey [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mails: paulabroisler@hotmail.com; juliananc@ig.com.br; sfsabato@ipen.br

    2007-07-01

    Mango (Mangifera indica L.) is a tropical fruit of great economical relevance in the world, mainly for tropical countries like Brazil. It consists in the second tropical fruit more important grown in the world. On the other hand it is a very perishable fruit and its delivery to distant points is restricted due to short shelf life at environmental temperature. Food irradiation process is applied to fruits for their preservation, once it promotes disinfestation and even maturation retard, among other mechanisms. The Brazilian legislation permits the food irradiation and does not restrict the doses to be delivered. In order to verify eventual changes, sensorial evaluation is very important to study how irradiation affects the quality of the fruit and its acceptability. Mangoes were irradiated in a Cobalto-60 source, from the Radiation Technology Center, CTR, of IPEN/CNEN-SP at doses 0,5 kGy e 0,75 kGy. The sensorial evaluation was measured through Acceptance Test where irradiated samples were offered together with control sample to the tasters who answered their perception through hedonic scale. The parameters Color, Odor, Flavor and Texture were analyzed. Statistical analysis showed that only Odor parameter was different from control (sample irradiated at 0.5 kGy). Few tasters indicated that irradiated mangoes had fewer odors in relation to non-irradiated samples. (author)

  6. Effects of irradiation upon spices

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    ESR studies were performed on untreated and irradiated samples of paprika powder, ground black pepper, and a spice mixture of the following composition: paprika, 55%; black pepper, 14%; allspice, 9%; coriander, 9%; marjoram, 7%; cumin, 4%; and nutmeg, 2%. Gamma radiation doses from 0.5 to 5 Mrad were applied. In the case of paprika samples, the effect of moisture content on the formation and disappearance of radiation-induced free radicals was also investigated. Shortly after irradiation (on the day of radiation treatment) high amounts of free radicals were detected in irradiated spice samples but they diminished upon storage. After a period of 3 months the ESR signals of the irradiated samples approximated those of the controls. The free radicals found in unirradiated ground spices did not disappear during a storage period as long as one year. The formation and disappearance of radiation-induced free radicals were found to be strongly affected by the moisture content of samples. If a sample of low moisture content containing a high free radical concentration after irradiation was placed in an atmosphere of higher moisture content, the free radicals decayed rapidly.

  7. Effect of electron beam irradiation on fisheries water

    International Nuclear Information System (INIS)

    Sarala Selambakkannu; Khomsaton Abu Bakar; Jamaliah Shariff; Suhairi Alimon

    2012-01-01

    This paper studies about water obtained from fish pond of fisheries research centre. Usual water quality parameters such as pH, COD, Turbidity and Ammonia content were analyzed before and after irradiation. Electron beam irradiation was used to irradiate the water with the dose 100 kGy, 200 kGy and 300 kGy. Only high dose was applied on this water as only a limited amount of samples was supplied. All the parameters indicated a slight increase after irradiation except for the ammonia content, which showed a gradual decrease as irradiation dose increases. Sample condition was changed before irradiation in order to obtain more effective results in the following batch. The water sample from fisheries was diluted with distilled water to the ratio of 1:1.This was followed with irradiation at 100 kGy, 200 kGy and 300 kGy. The results still showed an increase in all parameters after irradiation except for ammonia content. For the following irradiation batch, the pH of the sample was adjusted to pH 4 and pH 8 before irradiation. For this sample the irradiation dose selected was only 100 kGy. A higher value of ammonia was observed for the sample with pH 4 after irradiation. Other parameters were almost the same as the first two batches. (author)

  8. Development of UV absorbing PET through Electron Irradiation

    International Nuclear Information System (INIS)

    Kim, Jung Woo; Lee, Na Eun; Lim, Hyung San; Park, Yang Jeong; Cho, Sung Oh

    2017-01-01

    Experiment to increase UV absorbance through electron beam irradiation on PET was performed. Moreover, surface hardness and roughness of each sample were observed to find the key factor increasing UV absorbance. PET sheets were irradiated with an electron beam at various fluences. The irradiated samples, as well as pristine sample, were subjected to UV-visible spectral study(UV-Vis), pencil hardness test, and scanning electron microscopy(SEM) experiment. In this study, PET samples irradiated at several conditions were analyzed through various measurements. UV absorbance-another meaning of transmittance in this study- of irradiated PET sample increased compared with pristine sample as fluence was increased in UV-Visible spectroscopy experiment.

  9. Mechanical properties of irradiated beryllium

    International Nuclear Information System (INIS)

    Beeston, J.M.; Longhurst, G.R.; Wallace, R.S.

    1992-01-01

    Beryllium is planned for use as a neutron multiplier in the tritium breeding blanket of the International Thermonuclear Experimental Reactor (ITER). After fabricating samples of beryllium at densities varying from 80 to 100% of the theoretical density, we conducted a series of experiments to measure the effect of neutron irradiation on mechanical properties, especially strength and ductility. Samples were irradiated in the Advanced Test Reactor (ATR) to a neutron fluence of 2.6 x 10 25 n/m 2 (E > MeV) at an irradiation temperature of 75deg C. These samples were subsequently compression-tested at room temperature, and the results were compared with similar tests on unirradiated specimens. We found that the irradiation increased the strength by approximately four times and reduced the ductility to approximately one fourth. Failure was generally ductile, but the 80% dense irradiated samples failed in brittle fracture with significant generation of fine particles and release of small quantities of tritium. (orig.)

  10. Mechanical properties of irradiated beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Beeston, J.M.; Longhurst, G.R.; Wallace, R.S. (EG and G Idaho, Inc., Idaho Falls, ID (United States). Idaho National Engineering Lab.); Abeln, S.P. (EG and G Rocky Flats, Inc., Golden, CO (United States))

    1992-10-01

    Beryllium is planned for use as a neutron multiplier in the tritium breeding blanket of the International Thermonuclear Experimental Reactor (ITER). After fabricating samples of beryllium at densities varying from 80 to 100% of the theoretical density, we conducted a series of experiments to measure the effect of neutron irradiation on mechanical properties, especially strength and ductility. Samples were irradiated in the Advanced Test Reactor (ATR) to a neutron fluence of 2.6 x 10[sup 25] n/m[sup 2] (E > MeV) at an irradiation temperature of 75deg C. These samples were subsequently compression-tested at room temperature, and the results were compared with similar tests on unirradiated specimens. We found that the irradiation increased the strength by approximately four times and reduced the ductility to approximately one fourth. Failure was generally ductile, but the 80% dense irradiated samples failed in brittle fracture with significant generation of fine particles and release of small quantities of tritium. (orig.).

  11. Mechanical properties of irradiated beryllium

    Science.gov (United States)

    Beeston, J. M.; Longhurst, G. R.; Wallace, R. S.; Abeln, S. P.

    1992-10-01

    Beryllium is planned for use as a neutron multiplier in the tritium breeding blanket of the International Thermonuclear Experimental Reactor (ITER). After fabricating samples of beryllium at densities varying from 80 to 100% of the theoretical density, we conducted a series of experiments to measure the effect of neutron irradiation on mechanical properties, especially strength and ductility. Samples were irradiated in the Advanced Test Reactor (ATR) to a neutron fluence of 2.6 × 10 25 n/m 2 ( E > 1 MeV) at an irradiation temperature of 75°C. These samples were subsequently compression-tested at room temperature, and the results were compared with similar tests on unirradiated specimens. We found that the irradiation increased the strength by approximately four times and reduced the ductility to approximately one fourth. Failure was generally ductile, but the 80% dense irradiated samples failed in brittle fracture with significant generation of fine particles and release of small quantities of tritium.

  12. Thermoluminescence and chemiluminescence measurement as routine screening method for identification of irradiated spices. Studies to establish limiting values for differentiation of irradiated and non-irradiated samples. Thermolumineszenz- und Chemilumineszenzmessungen als Routine-Methoden zur Identifizierung strahlenbehandelter Gewuerze. Untersuchungen zur Festlegung von Grenzwerten fuer die Unterscheidung bestrahlter von unbestrahlten Proben

    Energy Technology Data Exchange (ETDEWEB)

    Heide, L; Albrich, S; Mentele, E; Boegl, W

    1987-04-01

    The reported experiments with non-irradiated and ..gamma..-irradiated spices of different origin were conducted to determine the variation in chemiluminescence and thermoluminescence intensity for each individual spice. 29 spices from 7 to 10 different manufacturers have been examined, taking into account the influence of storage time. In order to evaluate the methods, the results are represented in diagrams and tables enabling light emission limits to be given for differentiation between irradiated and non-irradiated samples. The final section of this report contains a conclusive evaluation of the present state of chemiluminescence and thermoluminescence analysis for the detection of irradiated spices.

  13. Combined therapy using Q-switched ruby laser and bleaching treatment with tretinoin and hydroquinone for periorbital skin hyperpigmentation in Asians.

    Science.gov (United States)

    Momosawa, Akira; Kurita, Masakazu; Ozaki, Mine; Miyamoto, Shinpei; Kobayashi, Yo; Ban, Izumi; Harii, Kiyonori

    2008-01-01

    Periorbital skin hyperpigmentation, so-called dark circles, is of major concern for many people. However, only a few reports refer to the morbidity and treatment, and as far as the authors know, there are no reports of the condition in Asians. A total of 18 Japanese patients underwent combined therapy using Q-switched ruby laser to eliminate dermal pigmentation following topical bleaching treatment with tretinoin aqueous gel and hydroquinone ointment performed initially (6 weeks) to reduce epidermal melanin. Both steps were repeated two to four times until physical clearance of the pigmentation was confirmed and patient satisfaction was achieved. Skin biopsy was performed at baseline in each patient and at the end of treatment in three patients, all with informed consent. Clinical and histologic appearances of periorbital hyperpigmentation were evaluated and rated as excellent, good, fair, poor, or default. Seven of 18 patients (38.9 percent) showed excellent clearing after treatment and eight (44.4 percent) were rated good. Only one (5.6 percent) was rated fair and none was rated poor. Postinflammatory hyperpigmentation was observed in only two patients (11.1 percent). Histologic examination showed obvious epidermal hyperpigmentation in 10 specimens. Dermal pigmentation was observed in all specimens but was not considered to be melanocytosis. Remarkable reduction of dermal pigmentation was observed in the biopsy specimens of three patients after treatment. The new treatment protocol combining Q-switched ruby laser and topical bleaching treatment using tretinoin and hydroquinone is considered effective for improvement of periorbital skin hyperpigmentation, with a low incidence of postinflammatory hyperpigmentation.

  14. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Juergen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Aaron, A. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bell, Gary L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burgess, Thomas W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ellis, Ronald James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giuliano, D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kiggans, James O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lessard, Timothy L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ohriner, Evan Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Perkins, Dale E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Varma, Venugopal Koikal [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-10-20

    -state heat fluxes of 5–20 MW/m2 and ion fluxes up to 1024 m-2s-1. Since PFCs will have to withstand neutron irradiation displacement damage up to 50 dpa, the target station design must accommodate radioactive specimens (materials to be irradiated in HFIR or at SNS) to enable investigations of the impact of neutron damage on materials. Therefore, the system will have to be able to install and extract irradiated specimens using equipment and methods to avoid sample modification, control contamination, and minimize worker dose. Included in the design considerations will be an assessment of all the steps between neutron irradiation and post-exposure materials examination/characterization, as well as an evaluation of the facility hazard categorization. In particular, the factors associated with the acquisition of radioactive specimens and their preparation, transportation, experimental configuration at the plasma-specimen interface, post-plasma-exposure sample handling, and specimen preparation will be evaluated. Neutronics calculations to determine the dose rates of the samples were carried out for a large number of potential plasma-facing materials.

  15. Utilization of irradiation on food preservation

    International Nuclear Information System (INIS)

    Cho, Han Ok; Kwon, Joong Ho; Byun, Myung Woo

    1985-04-01

    The number of total viable bacteria in chicken meat was reduced by over 90% with irradiation treatments of 5-10 kGy, and also an irradiation dose of yeasts, molds, coliforms, and especially Salmonella for 2-4 weeks of storage. In physicochemical properties of stored chichen, such as water holding capacity, TBA number, UBN, odor, color, overall appearance, cooking quality and organoleptic characteristics, the irradiated samples were superior to the nonirradiated samples, so the freshness of irradiated chicken was retained until 30 days ofter storage at 3-4degC. Commercial fried fish paste was comtaminated by 2.2x10 3 counts in total variable bacteria, 2.8x10 2 counts in yeasts and models, and 1.0x10 2 counts in coliforms, per gram of samples, but irradiation treatment of more than 3 kGy could reduce the microbial load up to 80-90%. As the storage period increased, chemical components of the irradiated samples were better than those of the nonirradiated samples, and the self-life of irradiated groups was extended by 3-4 times as compared with that of nonirradiated groups at room(10-20degC) and low(3-4degC) temperatures without apparent changes in organoleptic properties. Some packaged dried fishes, such as dried cod, dried squid, dried file fish and dried pollack, were preserved by irradiation under the room condictions. After storage of one year the by irradiated samples with doses of 3-8 kGy were found to be marketable resulting from organoleptic observations without showing any storage loss due to microbial and insect factors. (Author)

  16. Evaluation of fungal bio burden and mycotoxins presence in irradiated samples of medicinal plants purchased from wholesale and retail market

    International Nuclear Information System (INIS)

    Aquino, Simone

    2007-01-01

    This present study evaluated the effect of gamma radiation on the fungal survival in packed medicinal plants, purchased from wholesale and retail market, in different period (0 and 30 days) after the treatment. Five kind of medicinal plants (Peumus boldus, Camellia sinensis, Maytenus ilicifolia, Paullinia cupana and Cassia angustifolia), were collected from different cities of Sao Paulo State, and submitted to irradiation treatment using a 60 Co source (type Gammacell 220) with doses of 5,0 kGy and 10 kGy and at dose rate of 3.0 kGy/h. Non-irradiated samples (control group) were used for fungal counts and serial dilutions from 10 -1 to 10 -6 of the samples were seeded in duplicates and plated using the surface culture method in Dichloran 18% Glycerol Agar (DG 18) and were counted after five days at 25 deg C. The control group revealed the presence of genera Aspergillus and Penicillium, which are known as toxigenic fungi and a few samples of control group were within the safety limits of World Health Organization (WHO, 1998) to medicinal plants. In response to resistance of ionizing treatment, in the dose of 5 kGy, it was observed that the genera Aspergillus, Phoma and Syncephalastrum were radio-resistant after the process (day 0 and 30th day). The treatment by gamma radiation was effective in decontamination of all irradiated samples of medicinal plants, after 30 days, with the dose of 10 kGy and kept of veiled conditions. It was not detected aflatoxins in samples of control group, even though these samples were heavily contaminated with Aspergillus flavus. (author)

  17. Studies On Quality Criteria For Irradiated Breaded Chicken Breast Fillets

    International Nuclear Information System (INIS)

    HASSAN, I.M.; IBRAHIM, M.T.; MAHMOUD, A.A.; SHAMS EL DIN, N.M.M.; MOHAMMAD, M.K.

    2010-01-01

    Quality criteria of irradiated breaded chicken breast fillets were studied. Fresh boneless and skinless breaded chicken breast meats samples were divided into four separate batches and packed in plastic bags and sealed by an impulse sealer. Samples in plastic bags were exposed to different doses of gamma irradiation (2.5, 5 and 7 kGy) at ambient temperature. Just after irradiation, the samples were stored at 4 ±1 0 C. All samples were evaluated for microbiological, chemical and sensorial properties after irradiation and throughout the storage periods. During storage, the total bacterial count was significantly increased (P<0.05) in all samples with higher rates of increase in non-irradiated samples. In all irradiated samples, Staphylococcus aureus did not detected up to 6 days then detected after 22 days in samples treated with 2.5 kGy as well as 31 days in samples treated with 5 kGy. On the other hand, Staphylococcus aureus was detected after 45 days in samples treated with 7 kGy. Salmonella sp., Listeria monocytogenes and Campylobacter jejuni could not detected in untreated and treated samples. The protein content showed significant decrease immediately after irradiation and during the refrigerated storage. The TVN values for non-irradiated samples were significantly higher (P<0.05) than irradiated samples. The present data showed significant decrease (P<0.05) in protein solubility percentages of irradiated samples at day 0 and 6 of refrigerated storage. The observed decrease was related to the increase of radiation dose. At the end of storage period (62 days), 2.5 kGy samples were significantly higher in TBA values than other irradiated samples. On the other hand, irradiation was significantly reduced (P<0.05) the amount of major mono unsaturated and poly unsaturated fatty acids. Sensory attributes of breaded chicken breast fillets did not affected by irradiation. It could be concluded that irradiation dose of 5 kGy can be used in chicken samples stored in

  18. Mechanical properties of irradiated and non-irradiated Zr1%Nb and Zircaloy claddings

    International Nuclear Information System (INIS)

    Griger, Agnes

    2004-01-01

    The mechanical properties of irradiated and non-irradiated Zr1%Nb were determined and they were compared with the analogous properties of Zircaloy-4 to establish connections between the evolution of mechanical parameters of Zr1%Nb and Zircaloy-4 cladding materials and the measure of irradiation. Samples were irradiated in the vertical channels of the Budapest Research Reactor for different time periods at 50-65 C temperature. The measure of irradiation (fluent) for different samples was estimated by means of flux measurement and using the effective irradiation time. Post irradiation uniaxial tension tests in transverse direction were carried out on ring specimens. The mechanical parameters of the Zr1%Nb alloy significantly improve due to the effect of irradiation. However, the values of mechanical parameters do not further increase when the fluent increases above 10 20 n/cm 2 . These results are in good accordance with the Russian ones [1]. Contrary to the behaviour of Zr1%Nb alloy, the mechanical parameters of the Zircaloy practically do not change on the effect of irradiation. The originally high values of ultimate tensile strength and yield stress change only slightly with the increasing fluent in the investigated fluent-region. (Author)

  19. Irradiated target cooling using circular air jet

    International Nuclear Information System (INIS)

    Selvaraj, P.; Natesan, K.; Velusamy, K.; Baskaran, V.; Sundararajan, T.

    2015-01-01

    To study the effect of irradiation on materials, sample coupons are irradiated in cyclotron facilities. During the irradiation process, these samples produce significant heat. This heat needs to be continuously removed from the samples in order to avoid melting of the samples as well as to keep the samples at a particular temperature during irradiation. The area available for heat transfer is limited due to the small size of the samples. To increase the heat transfer rate, jet cooling is used as it provides large heat transfer co-efficient. To understand the heat transfer characteristics of jet cooling under these conditions, experiments have been carried out. Electric Joule heating is adopted to simulate irradiation heat in stainless steel samples. An array of circular nozzles is used to create air jet. From the study the values of the parameters correspond to the maximum heat removal rate are found out. The results are also compared with an empirical correlation from the literature. (author)

  20. Thermal analysis applied to irradiated propolis

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, Andrea Harumi; Machado, Luci Brocardo; Mastro, N.L. del E-mail: nelida@usp.br

    2002-03-01

    Propolis is a resinous hive product, collected by bees. Raw propolis requires a decontamination procedure and irradiation appears as a promising technique for this purpose. The valuable properties of propolis for food and pharmaceutical industries have led to increasing interest in its technological behavior. Thermal analysis is a chemical analysis that gives information about changes on heating of great importance for technological applications. Ground propolis samples were {sup 60}Co gamma irradiated with 0 and 10 kGy. Thermogravimetry curves shown a similar multi-stage decomposition pattern for both irradiated and unirradiated samples up to 600 deg. C. Similarly, through differential scanning calorimetry , a coincidence of melting point of irradiated and unirradiated samples was found. The results suggest that the irradiation process do not interfere on the thermal properties of propolis when irradiated up to 10 kGy.

  1. Control of food irradiation in Denmark

    International Nuclear Information System (INIS)

    Leth, T.

    1996-01-01

    In Denmark food irradiation is not allowed. However, with the consideration within EEC about directives regulating food irradiation and the development of methods for detection, it has been found necessary to ascertain that illegally irradiated foods are not found on the Danish market. Irradiation of spices is allowed in many countries even without being declared in the foods. It thus seemed logical to begin the control of food irradiation by screening a number of spices. This resulted in 1992 in the assessment of 105 samples and in 1993 of 48 samples. (author)

  2. Further study of the glassy low-temperature properties of irradiated crystalline quartz: neutron and electron irradiation

    International Nuclear Information System (INIS)

    Laermans, C.; Daudin, B.

    1979-01-01

    Recently it has been shown that a quartz crystal after light fast neutron irradiation shows low temperature hypersonic properties which are similar to those found in glasses although the sample was still crystalline. Additional measurements have been carried out in the neutron-irradiated sample and a sample irradiated with high energy electrons has also been investigated. (Fast neutron dose 6 x 10 18 n/cm 2 , 2 MeV electron dose 3 x 10 19 e/cm 2 ). A magnetic field up to 1.5 T was found to have no influence in the hypersonic saturation behaviour of the neutron-irradiated sample (9 GHz, 1.65 K) and thermal conductivity measurements are consistent with a number of two level systems (2 LS) an order of magnitude lower than in vitreous silica as found before. Low temperature hypersonic measurements as a function of acoustic intensity and temperature as well as thermal conductivity measurements give no evidence for the presence of 2 LS in the electron irradiated sample. Considering the damage created in both samples this indicates that 2 LS are probably not related to point defects

  3. Evaluation of dynamic elasticity module in samples of Portland (type 1) cement paste exposed to neutronic irradiation

    International Nuclear Information System (INIS)

    Rosa Junior, A.A.; Lucki, G.

    1986-01-01

    The fast neutron radiation effects and temperature on Portland cement are studied. The Dynamic Elasticity Module (Ed) in samples of Portland cement paste was evaluated. Ultrassonic technics were applied (resonance frequency and pulse velocity). The samples were irradiated with fast neutrons to fluence of 7,2 x 10 18 n/cm 2 (E approx. 1 MeV), at temperature of 120 + - 5 0 C, due to gamma heating. This temperature was simulated in laboratory in a microwave oven. (Author) [pt

  4. Effect of alpha self irradiation on helium migration in (U,Pu)O2 samples

    International Nuclear Information System (INIS)

    Pipon, Yves; Roudil, Daniele; Jegou, Christophe; Khodja, Hicham; Raepsaet, Caroline

    2008-01-01

    The helium behavior and its migration mechanisms in nuclear spent fuel (UOX and MOX) significantly impact the possible evolution of the spent fuel matrix in a closed system during interim storage or during a disposal repository. An experimental study has been conducted on (U,Pu)O 2 samples in order to investigate the impact of defects created by alpha decay on helium diffusion. One large part is devoted to thermal atomic diffusion and applied on 3 He implanted samples, annealed at 850 and 1000 deg. C. The He profiles, as implanted and after annealing, were investigated with the 3 He(d,p) 4 He nuclear reaction. Another part deals with the thermal release of 4 He amassed in the samples. The measured thermal diffusion coefficients are compared with previously published values, thereby highlighting the effect of the alpha self-irradiation on helium behavior. (authors)

  5. Detection of the irradiated domestic potato by thermoluminescence analysis

    International Nuclear Information System (INIS)

    Nakauma, M.; Saitou, K.; Todoriki, S.

    2004-01-01

    The applicability of thermoluminescence (TL) method to the detection of Japanese domestic potatoes was examined. Potatoes of nine different origins were exposed to gamma rays at O to 150Gy and the minerals separated from the potatoes were subjected to the TL measurements. The fading effects of TL emission intensity were also examined during the storage of post-irradiation period. The irradiated samples gave large intensity of TL signals compared with those of non-irradiated ones, and there were proportionalities in the intensity and the dose. The quantum yield of the TL emission for each unit weight and shape of glow curves were varied in the samples from different producing regions hence the irradiated samples were difficult to be detected by using those parameters. TL ratios obtained from the irradiated samples in all regions were 0.15-1.00 and those obtained from non-irradiated samples were less than 0.15. Therefore, the irradiated and non-irradiated samples can be distinguished by normalization (TL ratio). The signal intensity decreased with the storage time, and the reduction of signal was more rapidly observed in the sample stored under light condition than that in darkness. However, the TL ratio of the samples irradiated at 150 Gy and stored for five months could be distinguished from those of non-irradiated samples. It was also possible to apply this method to the detection of the domestic potatoes which irradiated in a commercial facility and purchased at a local market. (Received Oct. 22, 2003; Accepted Mar. 18, 2004)

  6. Post-irradiation stability of polyvinyl chloride at sterilizing doses

    International Nuclear Information System (INIS)

    Naimian, F.; Katbab, A.A.; Nazokdast, H.

    1994-01-01

    Post-irradiation stability of plasticized PVC irradiated by 60 Co gamma ray at sterilizing doses has been studied. Effects of irradiation upon chemical structure, mechanical properties and rheological behaviour of samples contained different amounts of Di(2-ethylhexyl)phthalate as plasticizer have been investigated. Formation of conjugated double bonds, carbonyl and hydroxyl groups have been followed by UV and FTIR spectrometers up to 6 months after irradiation. FTIR spectra of irradiated samples showed no significant changes in carbonyl and hydroxyl groups even 6 months after irradiation. However, changes in UV-visible spectra was observed for the irradiated samples up to 6 months post-irradiation. This has been attributed to the formation of polyenes which leads to the discoloration of this polymer. Despite a certain degree of discoloration, it appears that the mechanical properties of PVC are not affected by irradiation at sterilizing doses. No change in the melt viscosity of the irradiated PVC samples with post-irradiation was observed, which is inconsistent with the IR results. (author)

  7. UV irradiation of track membranes as a method for obtaining the necessary value of brittleness for good fractures of samples for sem observations

    International Nuclear Information System (INIS)

    Sartowska, B.; Nowicki, A.; Orelovitch, O.; )

    2006-01-01

    Synthesis of nano- and microstructures of materials inside the pores of specific template-track membranes can be used to obtain nano- and microwires or nano- and microtubes. It is important for these applications to know the inner geometry of the pores like sizes, shape and surface morphology. Scanning electron microscopy technique (SEM) was used predominantly for this kind of membrane characterisation. The use of other methods of sample preparation as electron, gamma rays or UV irradiation allows to make them more brittle. In present paper authors describe preliminary results of the tensile measurements of membranes after UV irradiation. Poly(ethylene terephthalate) (PET) membrane 10 μm thick with pore diameter 1.0 μm were prepared t the Joint Institute for Nuclear Research (Dubna, Russia) using the standard procedure. The samples were irradiated with UV light with energy flux 2.8 W/cm 2 during different periods of time. The tensile measurements of the initial and irradiated materials were carried in the Institute of Nuclear Chemistry and Technology (Warsaw, Poland). In conclusion, authors claim that it is possible to find the dose of UV irradiation that ensures the fracture without elastic deformation. In the case when the time of UV irradiation increases up to 90 h, the PET membrane breaks without distortion of its channel structure

  8. Robotic Irradiated Sample Handling Concept Design in Reactor TRIGA PUSPATI using Simulation Software

    International Nuclear Information System (INIS)

    Mohd Khairulezwan Abdul Manan; Mohd Sabri Minhat; Ridzuan Abdul Mutalib; Zareen Khan Abdul Jalil Khan; Nurfarhana Ayuni Joha

    2015-01-01

    This paper introduces the concept design of an Robotic Irradiated Sample Handling Machine using graphical software application, designed as a general, flexible and open platform to work on robotics. Webots has proven to be a useful tool in many fields of robotics, such as manipulator programming, mobile robots control (wheeled, sub-aquatic and walking robots), distance computation, sensor simulation, collision detection, motion planning and so on. Webots is used as the common interface for all the applications. Some practical cases and application for this concept design are illustrated on the paper to present the possibilities of this simulation software. (author)

  9. Non-equilibrium surface conditions and microstructural changes following pulsed laser irradiation and ion beam mixing of Ni overlayers on sintered alpha-SiC

    International Nuclear Information System (INIS)

    More, K.L.; Davis, R.F.

    1986-01-01

    Pulsed laser irradiation and ion beam mixing of thin Ni overlayers on sintered alpha-SiC have been investigated as potential surface modification techniques for the enhancement of the mechanical properties of the SiC. Each of these surface processing methods are nonequilibrium techniques; materials interactions can be induced at the specimen surface which are not possible with conventional thermal techniques. As a result of the surface modification, the physical properties of the ceramic can be altered under the correct processing conditions. Following laser irradiation using a pulsed ruby or krypton fluoride (KrF) excimer laser, the fracture strength of the SiC was increased by approximately 50 percent and 20 percent, respectively. However, ion-beam mixing of Ni on SiC resulted in no change in fracture strength. Cross-sectional transmission electron microscopy, scanning electron microscopy, secondary ion mass spectroscopy, and Rutherford backscattering techniques, have been used to characterize the extent of mixing between the Ni and SiC as a result of the surface modification and to determine the reason(s) for the observed changes in fracture strength. 19 references

  10. Identification of irradiated food additives by photostimulated luminescence (PSL) method

    International Nuclear Information System (INIS)

    Yun, Hye Jeong; Kwon, Joong Ho; KIm, Dong Ho; Hur, Jung Mu; Yang, Suh Yung; Lee, Byoung Hun

    2008-01-01

    Photostimulated luminescence (PSL), electron spin resonance (ESR) and thermoluminescence (TL) analyses were conducted to detect whether 258 kinds of extracted and powdered forms food additives were irradiated or not. In a view of the PSL results, 9 kinds of the extracted and powdered samples (3.2%) showed over 5,000 photon counts (60 sec) -1 and these samples were judged to be irradiation-positive. Thirty nine kinds of the samples (15.6%) yielded 700-5,000 photon counts (60 sec) -1 and these samples were grouped into irradiation-potential, while the samples showed below 700 photon counts (60 sec) -1 sec were judged to be irradiation-negative. TL glow curves for minerals separated from 5 samples were detected at 150 degrees C with high intensity. However, TL analysis did not apply to other irradiation-positive and irradiation-potential samples because the minerals for TL detection were not separated from the samples. ESR measurements for irradiation-positive and irradiation-potential samples, judged by PSL detection, showed no specific signals to irradiation. The results indicated that PSL could be applied to identify irradiation treatment of extracted and powdered food additives, while TL was optional and ESR was not suitable for detection extracted and powdered food additives

  11. Irradiated accelerated corrosion of stainless steel

    International Nuclear Information System (INIS)

    Raiman, S.S.; Wang, P.; Was, G.S.

    2015-01-01

    Type 316L stainless steel was exposed to a simulated PWR environment with in-situ proton irradiation to investigate the effect of simultaneous irradiation and corrosion. To enable these experiments, a dedicated beamline was constructed to transport a 3.2 MeV proton beam from a tandem accelerator, through the sample that also acts as the window between the beamline vacuum and a corrosion cell designed to flow primary water at 320 C. degrees and 13.1 MPa. Experiments were conducted on 316L stainless steel samples which were irradiated for 24 hours in 320 C. degrees water with 3 ppm H 2 , at dose rates of 7*10 -6 dpa/s and 7*10 -7 dpa/s, for 4, 24, and 72 hours. A dual-layer oxide formed on the samples, with an inner layer rich in Cr with Fe and Ni content, and an outer layer of Fe oxides. Samples were characterized with TEM (Transmission Electron Microscopy), EDS, and Raman spectroscopy to determine the effect of irradiation. Irradiated samples were found to have a thinner and more porous inner oxide which was deficient in chromium. The outer oxide was found to have significant hematite content, suggesting that irradiation led to an increase in ECP (Electro-Chemical Potential) at the oxide-solution interface, causing accelerated dissolution of the oxide under irradiation. (authors)

  12. 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.

  13. 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

  14. Trace analysis of irradiated steel samples from hiroshima by laser ablation inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Helal, A.I.; Zahran, N.F.

    2000-01-01

    A double focusing (JEOL, PLASMAX2) and quadrupole (ELAN6000, Perkin Elmer) mass spectrometers were used for the quantitative analysis of trace elements in steel samples from Hiroshima. The quantification of the analytical results was carried out using steel 468 as a standard reference material. The relative sensitivity coefficients (RSC's) for most of the elements varied between 0.12 and 2.93. The effect of iron as a matrix and the non-spectroscopic interferences are studied. Comparison of the results obtained on two steel samples from Hiroshima with that obtained on steel 468 standard reference materials demonstrated that there is no significant difference between them. Therefore, it is possible to say that the irradiated steel samples from Hiroshima have nearly the same specifications of trace element content as those of the normal steel samples

  15. Microstructural examination of irradiated zircaloy-2 pressure tube material

    International Nuclear Information System (INIS)

    Srivastava, D.; Tewari, R.; Dey, G.K.; Sah, D.N.; Banerjee, S.

    2005-01-01

    Irradiation induced microstructural changes in Zr alloys strongly influence the creep, growth and mechanical properties of pressure tube material. Since dimensional changes and mechanical property degradation can limit the life of pressure tube, it is essential to study and develop an understanding of the microstructure produced by neutron irradiation, by examining samples taken from the irradiated components. In the present work, an effort has been made to examine, microstructure of the Zircaloy-2 pressure tube material irradiated in the Indian Pressurized Heavy Water Reactor (PHWR). The present work is a first step towards a comprehensive program of characterization of microstructure of reactor materials after irradiation to different fluence levels in power reactors. In this study, samples from a Zircaloy-2 pressure tube, which had been in operation in the high flux region of Rajasthan Atomic Power Station Unit 1, for a period for 6.77 effective full power years (EFPYs), have been prepared and examined. The samples selected from the tube are expected to have a cumulative radiation damage of about 3 dpa. Samples prepared from the off cuts of RAPS-1 pressure tubes were also studied for examining the unirradiated microstructure of the material. The samples were examined in a 200kV JEOL 2000 FX microscope. This paper presents the distinct features observed in irradiated sample and a comprehensive comparison of the microstructures of the unirradiated and irradiated material. The effect of annealing on the annihilation of the defects generated during irradiation has been also studied. The bright field micrographs revealed that microstructure of the irradiated samples was different in many respects from the microstructure of the unirradiated samples. The presence of defect structure in the form of loops etc could be seen in the irradiated sample. These loops were mostly c-type loops lying in the basal plane. The dissolution and redistribution of the precipitates were

  16. Detection of garlic gamma-irradiated by assay comet

    International Nuclear Information System (INIS)

    Moreno Alvarez, Damaris L.; Miranda, Enrique F. Prieto; Carro, Sandra; Iglesias Enrique, Isora; Matos, Wilberto

    2009-01-01

    The garlic samples were irradiated in a facility with 60 Co sources, at absorbed dose values of 0-0,15 kGy. The detection method utilized for the identification of the irradiated garlic was biological comet assay. The samples were classified post-irradiation several times. The irradiated samples showed high strand breaks of DNA exhibiting comets of several forms, while the not irradiated and lower dose samples showed a behavior like round shape and light comets. Significant differences were found for higher absorbed dose values at 0.06 kGy, this absorbed dose value is corresponding with the applied dose value at this food in order to avoid the germination. (author)

  17. Irradiating cell samples in an x-ray radiation cabinet-the effect of tube filtration

    International Nuclear Information System (INIS)

    Parkin, Adrian; Wright, Ian; Yates, Stuart; Goldstone, Karen E; Russell, Paul; Starr, Christy

    2004-01-01

    The cell irradiation cabinet described is used for creating DNA damage in cell samples in order to study tumourigenesis. The medical research laboratory involved was using the manufacturer's quoted dose rate (32.2 mGy s -1 ) to determine the required exposure time to impart a dose of 10 Gy. The x-ray output was investigated when the exposure failed to produce cell cycle arrest. The x-ray tube was fitted with only a 0.76 mm beryllium filter, and the spectrum therefore contained a high proportion of low energy photons which were being removed by the polystyrene sample flask as demonstrated by dose measurements in air and through the sample flask. Incorporation of a 0.5 mm aluminium filter removed most of these low energy photons but greatly reduced the dose rate to 3.8 mGy s -1 . The manufacturer's quoted dose rates from a lightly filtered tube are misleading: the contribution of the very low energy component of the spectrum to the dose is not relevant since it will be removed by a sample flask. (note)

  18. Detection of irradiated spices by thermoluminescence analysis

    International Nuclear Information System (INIS)

    Hammerton, K.M.; Banos, C.

    1996-01-01

    Spices are used extensively in prepared foods. The high levels of contamination of many spices with microorganisms poses a problem for the food industry. Irradiation treatment is the most effective means of reducing the microbial load to safe levels. Although the process is currently subject to a moratorium in Australia, it is used in several countries for the decontamination of spices. Methods for detecting irradiation treatment of spices are necessary to enforce compliance with labelling requirements or with a prohibition on the sale of irradiated foods. Thermoluminescence (TL) analysis of spice samples has been shown to be an applicable method for the detection of all irradiated spices. It was established that the TL response originates from the adhering mineral dust in the sample. Definitive identification of many irradiated spices requires the separation of a mineral extract from the organic fraction of the spice sample. This separation can be achieved by using density centrifugation with a heavy liquid, sodium polytungstate. Clear discrimination between untreated and irradiated spice samples has been obtained by re-irradiation of the mineral extract after the first TL analysis with an absorbed dose of about 1 kGy (normalisation). The ratio of the first to second TL response was about one for irradiated samples and well below one for untreated samples. These methods have been investigated with a range of spices to establish the most suitable method for routine control purposes. (author)

  19. Simulated Irradiation of Samples in HFIR for use as Possible Test Materials in the MPEX (Material Plasma Exposure Experiment) Facility

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Ronald James [ORNL; Rapp, Juergen [ORNL

    2014-01-01

    The importance of Plasma Material Interaction (PMI) is a major concern in fusion reactor design and analysis. The Material-Plasma Exposure eXperiment (MPEX) facility will explore PMI under fusion reactor plasma conditions. Samples with accumulated displacements per atom (DPA) damage produced by irradiations in the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) will be studied in the MPEX facility. The project presented in this paper involved performing assessments of the induced radioactivity and resulting radiation fields of a variety of potential fusion reactor materials. The scientific code packages MCNP and SCALE were used to simulate irradiation of the samples in HFIR; generation and depletion of nuclides in the material and the subsequent composition, activity levels, gamma radiation fields, and resultant dose rates as a function of cooling time. These state-of-the-art simulation methods were used in addressing the challenge of the MPEX project to minimize the radioactive inventory in the preparation of the samples for inclusion in the MPEX facility.

  20. Thermoluminescence analysis of irradiated oyster shells

    International Nuclear Information System (INIS)

    Cruz-Zaragoza, E.; Marcazzó, J.; Della Monaca, S.; Boniglia, C.; Gargiulo, R.; Bortolin, E.

    2012-01-01

    This paper reports the thermoluminescence (TL) analysis performed on the oyster shells powder. TL response of 60 Co gamma-rays irradiated samples were studied in the range from 80 Gy to 8 kGy doses. TL signal of irradiated shell powder was higher as compared to the unirradiated control samples, which allowed to identify the irradiated oysters. Results show that the oyster shells have good TL properties and can be useful for the identification of irradiated seafood as well as for the evaluation of the treatment dose. - Highlights: ► TL properties of irradiated oyster shell powder were studied. ► The SEM analysis shows that several elements are present in oyster shell powder. ► Calcite is the main component in the samples and β-calcite is also present. ► Following the European Standard EN 1788, the irradiated oyster can be identified. ► Determination of absorbed dose is possible by performing a preheat treatment.

  1. Safety report for the independent CO2 loop for cooling the samples irradiated in the vertical experimental channels of the RA reactor

    International Nuclear Information System (INIS)

    Pavlovic, A.; Zivkovic, S.; Milosevic, M.; Strugar, P.

    1969-01-01

    Independent CO 2 loop was designed for cooling the samples irradiated in the vertical experimental channels in the region of heavy water or in the graphite reflector. It is considered as a significant improvement of the RA reactor experimental possibilities. Six 'heads' are placed in vertical experimental channels and connected in parallel with the outer loop which contains out-of-reactor equipment. It is planned to irradiate samples in the 'heads' of the loop for the needs of Hot laboratory and Laboratory for reactor materials. Heat generated during sample irradiation is removed by CO 2 circulation. This report contains detailed description of the main loop, auxiliary systems, calculation results of anti reactivity and activation of construction materials of the low-temperature CO 2 loop. A separate chapter is devoted to control and regulation of temperature and pressure. Testing of the fundamental parameters of the coolant loop showed that it could fulfill more demanding tasks than designed by the project. Annex of this report includes results of leak testing for the loop 'heads' in vertical experimental channels VEK-6 and VEK-8 by helium leak detector [sr

  2. Detection of garlic gamma-irradiated by assay comet

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Alvarez, Damaris L.; Miranda, Enrique F. Prieto; Carro, Sandra; Iglesias Enrique, Isora; Matos, Wilberto [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), Ciudad de La Habana (Cuba)], e-mail: damaris@ceaden.edu.cu

    2009-07-01

    The garlic samples were irradiated in a facility with {sup 60}Co sources, at absorbed dose values of 0-0,15 kGy. The detection method utilized for the identification of the irradiated garlic was biological comet assay. The samples were classified post-irradiation several times. The irradiated samples showed high strand breaks of DNA exhibiting comets of several forms, while the not irradiated and lower dose samples showed a behavior like round shape and light comets. Significant differences were found for higher absorbed dose values at 0.06 kGy, this absorbed dose value is corresponding with the applied dose value at this food in order to avoid the germination. (author)

  3. Development of detection methods for irradiated foods

    International Nuclear Information System (INIS)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung; Kim, Kyong Su

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks

  4. Development of detection methods for irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung [Korea Atomic Energy Research Insitiute, Taejon (Korea, Republic of); Kim, Kyong Su [Chosun University, Kwangju (Korea, Republic of)

    1999-04-01

    To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks.

  5. Light and electron microscopic analysis of tattoos treated by Q-switched ruby laser

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, C.R.; Anderson, R.R.; Gange, R.W.; Michaud, N.A.; Flotte, T.J. (Massachusetts General Hospital, Boston (USA))

    1991-07-01

    Short-pulse laser exposures can be used to alter pigmented structures in tissue by selective photothermolysis. Potential mechanisms of human tattoo pigment lightening with Q-switched ruby laser were explored by light and electron microscopy. Significant variation existed between and within tattoos. Electron microscopy of untreated tattoos revealed membrane-bound pigment granules, predominantly within fibroblasts and macrophages, and occasionally in mast cells. These granules contained pigment particles ranging from 2-in diameter. Immediately after exposure, dose-related injury was observed in cells containing pigment. Some pigment particles were smaller and lamellated. At fluences greater than or equal to 3 J/cm2, dermal vacuoles and homogenization of collagen bundles immediately adjacent to extracellular pigment were occasionally observed. A brisk neutrophilic infiltrate was apparent by 24 h. Eleven days later, the pigment was again intracellular. Half of the biopsies at 150 d revealed a mild persistent lymphocytic infiltrate. There was no fibrosis except for one case of clinical scarring. These findings confirm that short-pulse radiation can be used to selectively disrupt cells containing tattoo pigments. The physial alteration of pigment granules, redistribution, and elimination appear to account for clinical lightening of the tattoos.

  6. Interactions of secondary particles with thorium samples in the setup QUINTA irradiated with 6 GeV deuterons

    Energy Technology Data Exchange (ETDEWEB)

    Khushvaktov, J., E-mail: khushvaktov@jinr.ru [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute of Nuclear Physics ASRU, Tashkent (Uzbekistan); Adam, J. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Nuclear Physics Institute ASCR PRI (Czech Republic); Baldin, A.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute for Advanced Studies “OMEGA”, Dubna (Russian Federation); Chilap, V.V. [Center of Physical and Technical Projects “Atomenergomash”, Moscow (Russian Federation); Furman, V.I.; Sagimbaeva, F.; Solnyshkin, A.A.; Stegailov, V.I.; Tichy, P.; Tsoupko-Sitnikov, V.M.; Tyutyunnikov, S.I.; Vespalec, R. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Vrzalova, J. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Nuclear Physics Institute ASCR PRI (Czech Republic); Yuldashev, B.S. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute of Nuclear Physics ASRU, Tashkent (Uzbekistan); Wagner, V. [Nuclear Physics Institute ASCR PRI (Czech Republic); Zavorka, L.; Zeman, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation)

    2016-08-15

    The natural uranium assembly, QUINTA, was irradiated with 6 GeV deuterons. The {sup 232}Th samples were placed at the central axis of the setup QUINTA. The spectra of gamma rays emitted by the activated {sup 232}Th samples have been analysed and more than one hundred nuclei produced have been identified. For each of those products, reaction rates have been determined. The ratio of the weight of produced {sup 233}U to {sup 232}Th is presented. Experimental results were compared with the results of Monte Carlo simulations by FLUKA code.

  7. Interactions of secondary particles with thorium samples in the setup QUINTA irradiated with 6-GeV deuterons

    International Nuclear Information System (INIS)

    Khushvaktov, J.H.; Yuldashev, B.S.; Adam, J.; Vrzalova, J.; Baldin, A.A.; Chilap, V.V.; Furman, V.I.; Sagimbaeva, F.; Solnyshkin, A.A.; Stegailov, V.I.; Tichy, P.; Tsoupko-Sitnikov, V.M.; Tyutyunnikov, S.I.; Vespalec, R.; Zavorka, L.; Wagner, V.; Zeman, M.

    2016-01-01

    The natural uranium assembly, QUINTA, was irradiated with 6-GeV deuterons. The 232 Th samples were placed at the central axis of the setup QUINTA. The spectra of gamma rays emitted by the activated 232 Th samples have been analysed, and more than one hundred nuclei produced have been identified. For each of those products, reaction rates have been determined. The ratio of the weight of produced 233 U to that of 232 Th is presented. Experimental results were compared with the results of Monte Carlo simulations by the FLUKA code. [ru

  8. Irradiation of meat products, chicken and use of irradiated spices for sausages

    International Nuclear Information System (INIS)

    Kiss, I.F.; Beczner, J.; Zachariev, Gy.; Kovacs, S.

    1990-01-01

    The shelf-life of packed minced meat has been increased at least threefold at 4 0 C by applying a 2 kGy dose. Results have been confirmed by detailed quantitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated and irradiated samples. The optimal average dose was 4 kGy for packed-frozen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterobacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. in 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices. (author)

  9. Irradiation of meat products, chicken and use of irradiated spices for sausages

    Energy Technology Data Exchange (ETDEWEB)

    Kiss, I.F.; Beczner, J.; Zachariev, Gy. (Central Food Research Inst., Budapest (Hungary)); Kovacs, S. (Veterinary and Food Control Centre, Budapest (Hungary))

    1990-01-01

    The shelf-life of packed minced meat has been increased at least threefold at 4{sup 0}C by applying a 2 kGy dose. Results have been confirmed by detailed quantitative microbiological examinations. Sensory evaluations show no significant difference between the unirradiated and irradiated samples. The optimal average dose was 4 kGy for packed-frozen chicken. The number of mesophilic aerobic microbes was reduced by 2, that of psychrotolerant by 2-3 and that of Enterobacteriaceae by 3-4 orders of magnitude by 4 kGy. S. aureus and Salmonella could not be detected in the irradiated samples. in 1984-1985 5100 kg irradiated chickens were marketed labelled as radiation treated. Irradiated spices (5 kGy) were used in the production of sausages (heat-treated and non-heat-treated) under industrial conditions. The microbiological contamination of irradiated spices was lower than that of ethylene oxide treated ones. The cell count in products made with irradiated spices was lower than in those made with unirradiated spices. The sausages proved to be of very good quality. In accordance with the permission, products were marketed and because of the low ratio of spices there was no need to declare them as using irradiated spices. (author).

  10. Detection of irradiated potato and garlic by thermoluminescence measurement

    International Nuclear Information System (INIS)

    Chung, H.W.; Kwon, J.H.

    1998-01-01

    Potato and garlic irradiated with gamma ray and electron beam at sprout-inhibition doses, 0.15 and 0.30 kGy were subjected to the detection whether they are irradiated or not by measuring thermoluminescence(TL) for the minerals adhering to the samples. Minerals extracted from the samples showed a high correlation coefficients between absorbed doses and corresponding TL responses. Nonirradiated samples, however, did not exhibit characteristic TL glowcurves. Major glowcurve peaks were observed at 200 to in all irradiated samples. TL intensity was proportional to irradiated doses, but it varied with the samples tested even at the same dose. It can be concluded from the results that detection of irradiated potato and garlic is possible by measuring TL for extracted minerals from the unknown samples

  11. Identification of irradiated spices with luminescence measurements: a European intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Heide, L; Guggenberger, R; Boegl, K W [Federal Health Office, Neuherberg/Muenchen (Germany, F.R.). Inst. for Radiation Hygiene

    1989-01-01

    Blind tests were performed measuring the thermoluminescence intensity on samples from 10 different spices that were either irradiated or unirradiated. The chemiluminescence was measured on 10 additional spice samples. Twelve institutions participated in this collaborative study. Thresholds were defined which, when exceeded, declare samples as irradiated. The recovering rate was nearly 100% for samples investigated by thermoluminescence. Only one out of 495 irradiated samples was not identified. By using chemiluminescence, the participants succeeded in identifying 99% of unirradiated samples and 75% of irradiated samples from a total of 490 samples. (author).

  12. Shallow irradiation of Citrus Unshiu by cathod ray, 2

    International Nuclear Information System (INIS)

    Takano, Hiroyuki; Kawashima, Koji; Umeda, Keiji

    1978-01-01

    The effect of 150 Krad cathode ray irradiation on the shelf life and quality of ''Citrus Unshiu'' was investigated. Citrus Unshiu (Japanese mandarin orange ''Satsuma'') were kept at 5 0 C for 2 months without pretreatment and irradiated. Both irradiated and non-irradiated samples were stored in the special storage boxes in which temperature, humidity and sterile air circulation were controlled. After 44 days, the percentage of spoiled oranges in irradiated and non-irradiated samples stored at 8 0 C were 57.5% and 64% respectively, on the other hand when stored at 3 0 C the percentage were 26% and 51% respectively. Rate of spoilage was significantly lower in the irradiated samples than non-irradiated ones. Irradiated effect on the shelf life extension was more conspicuous when the storage temperature was kept at 3 0 C. By the sensory examination, any difference for taste and flavor between irradiated and non-irradiated samples was not detected. The taste and flavor of the oranges stored at 8 0 C changed worse after long time storage but when stored at 3 0 C, such tendency was not observed. Undesirable odor and flavor were not detected by the panel with the irradiated samples in this experiment. The results showed that shelf life of the ''Citrus Unshiu'' could be extended by the combination of irradiation with 150 Krad cathode ray and storage at 3 0 C. (auth.)

  13. Detection of irradiated prawns by photostimulated luminescence

    International Nuclear Information System (INIS)

    Chen, Susu; Saito, Kimie; Hagiwara, Shoji; Todoriki, Setsuko; Nakajima, Mitsutoshi

    2011-01-01

    The purpose of this study was to investigate how photostimulated luminescence (PSL) can be applied to verify whether prawns have been irradiated by analyzing their intestinal tracts. Prawns from five different locations which were irradiated at doses of 1 kGy of γ-radiations were analyzed using the Japanese model PSL system. The results showed that the integrated photon counts of all the irradiated samples exceeded the upper threshold value (T 2 =4000 counts/90 s), whereas those of the non-irradiated samples were blew than the lower threshold value (T 1 =1000 counts/90 s). Moreover, using the other parameters which were decrease of intensity after optically stimulation and increase of intensity by optically stimulation, a clear difference was observed between non-irradiated and 1 kGy irradiated samples. Therefore, the Japanese model PSL system can be used as a screening method for detecting irradiated prawns by analyzing their intestinal tracts. (author)

  14. Microbiological, physicochemical, and sensory characteristics of gamma-irradiated fresh oysters during storage

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Sek; Pak, Jae Nam; Park, Jin Gyu; Han, In Jun; Jung, Pil Mun; Song, Beaom Seok; Choi, Jong Il; Kim, Jae Hun; Byun, Myung Woo; Lee, Ju Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Han, Sang Bae [Food and Risk Standardization Team, KFDA, Seoul (Korea, Republic of)

    2008-05-15

    The microbiological, physicochemical and sensory characteristics of gamma irradiated fresh oysters were evaluated regarding its shelf-life during refrigeration. Non-irradiated fresh oysters began to be putrefied after 14 days, while fresh oysters irradiated with 2 kGy showed 5.54 log CFU∙g-1 even after 28 days. Volatile basic nitrogen (VBN) value increased more rapidly in the non-irradiated sample than the irradiated samples during storage. Especially the VBN value of the non-irradiated sample was eight fold higher then that of the the sample irradiated with 2 kGy. The pH of the non-irradiated fresh oysters significantly decreased during storage while the samples irradiated with doses higher than 2 kGy showed no significant change. Thiobarbituric acid (TBA) value increased in all samples during a storage period, and gamma irradiation accelerated the increase of lipid oxidation. Sensory characteristics of fresh oysters were deteriorated as irradiation doses increased, and sensory scores of the samples irradiated with doses higher than 2 kGy were significantly decreased.

  15. Microbiological, physicochemical, and sensory characteristics of gamma-irradiated fresh oysters during storage

    International Nuclear Information System (INIS)

    Park, Jae Sek; Pak, Jae Nam; Park, Jin Gyu; Han, In Jun; Jung, Pil Mun; Song, Beaom Seok; Choi, Jong Il; Kim, Jae Hun; Byun, Myung Woo; Lee, Ju Woon; Han, Sang Bae

    2008-01-01

    The microbiological, physicochemical and sensory characteristics of gamma irradiated fresh oysters were evaluated regarding its shelf-life during refrigeration. Non-irradiated fresh oysters began to be putrefied after 14 days, while fresh oysters irradiated with 2 kGy showed 5.54 log CFU∙g-1 even after 28 days. Volatile basic nitrogen (VBN) value increased more rapidly in the non-irradiated sample than the irradiated samples during storage. Especially the VBN value of the non-irradiated sample was eight fold higher then that of the the sample irradiated with 2 kGy. The pH of the non-irradiated fresh oysters significantly decreased during storage while the samples irradiated with doses higher than 2 kGy showed no significant change. Thiobarbituric acid (TBA) value increased in all samples during a storage period, and gamma irradiation accelerated the increase of lipid oxidation. Sensory characteristics of fresh oysters were deteriorated as irradiation doses increased, and sensory scores of the samples irradiated with doses higher than 2 kGy were significantly decreased

  16. Design and deployment of semiochemical traps for capturing Anthonomus rubi Herbst (Coleoptera: Curculionidae) and Lygus rugulipennis Poppius (Hetereoptera: Miridae) in soft fruit crops

    DEFF Research Database (Denmark)

    Fountain, Michelle T.; Baroffio, Catherine; Borg-Karlson, Anna-Karin

    2017-01-01

    Strawberry blossom weevil (SBW), Anthonomus rubi Herbst (Coleoptera: Curculionidae) and European tarnished plant bug (ETB), Lygus rugulipennis Poppius (Hetereoptera: Miridae), cause significant damage to strawberry and raspberry crops. Using the SBW aggregation pheromone and ETB sex pheromone we...... if deployed at ground level and although a cross vane was not important for catches of ETB it was needed for significant captures of SBW. The potential for mass trapping SBW and ETB simultaneously in soft fruit crops is discussed including potential improvements to make this more effective and economic...

  17. Development of Irradiation Procedure for Gamma Irradiation Chamber Bio beam GM 8000

    International Nuclear Information System (INIS)

    Shuhaimi Shamsudin; Affrida Abu Hassan; Zaiton Ahmad; Abdul Rahim Harun; Ahmad Zainuri Mohd Dzomir

    2015-01-01

    Bio Beam GM 8000 gamma irradiation chamber obtained a conditional approval to operate on March 27, 2012, and later acquired a full approval on December 13, 2012. The objective for the procurement of this gamma chamber is to develop an acute irradiation facility for biological samples, including plants tissues, insects, pupae, microorganisms, as well as animal and human cells. To ensure a smooth and efficient operation, irradiation procedures were developed and improved over time. This paper discusses the operation and management of the Bio Beam GM 8000 facility, including irradiation procedures and sample preparation, application for services through online e-client system, consultancy, quality assurance and information dissemination to internal as well as external clients. In addition, this paper also discusses the potential, constraints and improvement measures taken to optimize the use of this facility in order to meet its objectives. (author)

  18. Bakery products from irradiated and unirradiated eggs - detection of irradiation in a processed food

    International Nuclear Information System (INIS)

    Pfordt, J.; Grabowski, H.U. von

    1995-01-01

    The detection of radiation-specific degradation products in fat has become an established method which has successfully been applied to egg products. This study is making evident the detectability of irradiated eggs as an ingredient of specified processed foods. Tart layers were produced from both irradiated and non-irradiated liquid whole egg. When the fat components were isolated from the tart layers and investigated by GC/MS, the presence of irradiated eggs could clearly be shown. While the radiation-induced hydrocarbons and 2-alkylcyclobutanones could not be found in unirradiated samples, tart layers from irradiated eggs contained these substances. Especially for the hydrocarbons a satisfying correlation between radiation dose and concentration could be observed. The concentrations of radiation-induced compounds were generally lower in the tart layers than in the liquid egg samples they had been produced from. (orig.) [de

  19. 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.

  20. Molecular diagnosis for the silk worm Bombyx Mori L. Viral and bacterial diseases in the irradiated and non-irradiated individuals

    International Nuclear Information System (INIS)

    Abulyazid, I.; Elshafei, A.; El-Said, E.; Mousa, S.; Taha, R.

    2007-01-01

    Genetic maps for the Bombyx Mori infectious flacherrie virus (BmlFV) causing flacherrie (Fl) disease and nuclear polyhedrosis virus (BmNPV) causing grasserie (Gr) disease were built up in an attempt to diagnose diseases early in young larval stages. For the non-irradiated and irradiated viral RNA of IFV, no amplification was obtained by using RT-PCR and RAPD-PCR techniques. HcoRI, EcoRV, BamHI, Hind III and BamHI restriction enzymes were used to digest the non-irradiated and irradiated viral DNA of BmNPV. It was found that, the two viral DNA samples were genetically different; the similarity indexes were 0.14, 0, 0, 0.18 and 0.15, respectively. At the biochemical level, native protein electrophoresis showed 4 and 3 new proteins in non-irradiated and irradiated Fl diseased larvae, respectively, while Gr diseased larvae showed 1 and 3 new protein types. The similarity index (S.I) between all the tested samples was not exceeded 44%. For lipoprotein pattern, 2 and 3 new lipoprotein types were appeared due to Fl disease in the non-irradiated and irradiated haemolymph samples, respectively, while Gr disease showed 3 new lipoproteins in the non-irradiated samples only. The highest S.I recorded was 56%. Glycoprotein pattern revealed 3 and 5 new glycoprotein types appeared due to Fl disease while Gr disease showed 4 and 6 new types in the non-irradiated and irradiated samples, respectively. The highest S.I was 77%. Fractionated protein with SDS revealed 2 common bands shared between the tested samples with R f values 0.28 and 0.71. Fl disease increased the number of protein bands with the appearance of 5 and 4 new proteins types. Gr disease reduced the total number of proteins with the appearance of 2 and 3 new types. The highest S.I was 59%. Both diseases and irradiation may be mutagenic through the epigenetic level in silkworm larvae leading to death. Thus, the results of the biochemical and genetic characterization of IFV and BmNPV enable us to conclude that the

  1. Dose controlled low energy electron irradiator for biomolecular films.

    Science.gov (United States)

    Kumar, S V K; Tare, Satej T; Upalekar, Yogesh V; Tsering, Thupten

    2016-03-01

    We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at -20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

  2. Dose controlled low energy electron irradiator for biomolecular films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. V. K., E-mail: svkk@tifr.res.in; Tare, Satej T.; Upalekar, Yogesh V.; Tsering, Thupten [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)

    2016-03-15

    We have developed a multi target, Low Energy Electron (LEE), precise dose controlled irradiator for biomolecular films. Up to seven samples can be irradiated one after another at any preset electron energy and dose under UHV conditions without venting the chamber. In addition, one more sample goes through all the steps except irradiation, which can be used as control for comparison with the irradiated samples. All the samples are protected against stray electron irradiation by biasing them at −20 V during the entire period, except during irradiation. Ethernet based communication electronics hardware, LEE beam control electronics and computer interface were developed in house. The user Graphical User Interface to control the irradiation and dose measurement was developed using National Instruments Lab Windows CVI. The working and reliability of the dose controlled irradiator has been fully tested over the electron energy range of 0.5 to 500 eV by studying LEE induced single strand breaks to ΦX174 RF1 dsDNA.

  3. Histological observation on dental hard tissue irradiated by ultrashort-pulsed laser

    Science.gov (United States)

    Uchizono, Takeyuki; Awazu, Kunio; Igarashi, Akihiro; Kato, Junji; Hirai, Yoshito

    2006-04-01

    In the field of dentistry, effectiveness of USPL irradiation is researched because USPL has less thermal side effect to dental hard tissue. In this paper, we observed morphological change and optical change of dental hard tissue irradiated by USPL for discussing the safety and effectiveness of USPL irradiation to dental hard tissues. Irradiated samples were crown enamel and root dentin of bovine teeth. Lasers were Ti:sapphire laser, which had pulse duration (P d)of 130 fsec and pulse repetition rate (f) of 1kHz and wavelength (l) of 800nm, free electron laser (FEL), which had P d of 15 μsec and f of 10Hz and wavelength of 9.6μm, and Er:YAG laser, which had P d of 250 μsec and f of 10Hz and wavelength of 2.94μm. After laser irradiation, the sample surfaces and cross sections were examined with SEM and EDX. The optical change of samples was observed using FTIR. In SEM, the samples irradiated by USPL had sharp and accurate ablation with no crack and no carbonization. But, in FEL and Er:YAG laser, the samples has rough ablation with crack and carbonization. It was cleared that the P/Ca ratio of samples irradiated by USPL had same value as non-irradiated samples. There was no change in the IR absorption spectrum between samples irradiated by USPL and non-irradiated sample. But, they of samples irradiated by FEL and Er:YAG laser, however, had difference value as non-irradiated samples. These results showed that USPL might be effective to ablate dental hard tissue without thermal damage.

  4. Identification of irradiated meat using electron spin resonance (ESR) spectroscopy and estimation of applied dose using re-irradiation

    International Nuclear Information System (INIS)

    Chawla, S.P.; Thomas, Paul; Bongirwar, D.R.

    2001-01-01

    An in-house blind trail on bone-in meat chunks was carried out in which 35 coded samples were correctly identified. The samples were either left unirradiated or had been irradiated to dose of 1, 2.5 or 4 kGy. Using re-irradiation, the dose received by the samples were determined with either linear, quadratic or exponential equation. The quadratic or exponential equation gave more successful estimates of irradiation dose whereas linear fit equations tend to over estimate the dose. (author)

  5. Monte Carlo studies for irradiation process planning at the Portuguese gamma irradiation facility

    International Nuclear Information System (INIS)

    Oliveira, C.; Salgado, J.; Botelho, M.L.M. Luisa; Ferreira, L.M.

    2000-01-01

    The paper describes a Monte Carlo study for planning the irradiation of test samples for microbiological validation of distinct products in the Portuguese Gamma Irradiation Facility. Three different irradiation geometries have been used. Simulated and experimental results are compared and good agreement is observed. It is shown that Monte Carlo simulation improves process understanding, predicts absorbed dose distributions and calculates dose uniformity in different products. Based on these results, irradiation planning of the product can be performed

  6. Void formation by annealing of neutron-irradiated plastically deformed molybdenum

    International Nuclear Information System (INIS)

    Petersen, K.; Nielsen, B.; Thrane, N.

    1976-01-01

    The positron annihilation technique has been used in order to study the influence of plastic deformation on the formation and growth of voids in neutron irradiated molybdenum single crystals treated by isochronal annealing. Samples were prepared in three ways: deformed 12-19% before irradiation, deformed 12-19% after irradiation, and - for reference purposes -non-deformed. In addition a polycrystalline sample was prepared in order to study the influence of the grain boundaries. All samples were irradiated at 60 0 C with a flux of 2.5 x 10 18 fast neutrons/cm 2 . After irradiation the samples were subjected to isochronal annealing. It was found that deformation before irradiation probably enhanced the formation of voids slightly. Deformation after irradiation strongly reduced the void formation. The presence of grain boundaries in the polycrystalline sample had a reducing influence on the growth of voids. (author)

  7. Emulation of neutron irradiation effects with protons: validation of principle

    International Nuclear Information System (INIS)

    Was, G.S.; Busby, J.T.; Allen, T.; Kenik, E.A.; Jensson, A.; Bruemmer, S.M.; Gan, J.; Edwards, A.D.; Scott, P.M.; Andreson, P.L.

    2002-01-01

    This paper presents the results of the irradiation, characterization and irradiation assisted stress corrosion cracking (IASCC) behavior of proton- and neutron-irradiated samples of 304SS and 316SS from the same heats. The objective of the study was to determine whether proton irradiation does indeed emulate the full range of effects of in-reactor neutron irradiation: radiation-induced segregation (RIS), irradiated microstructure, radiation hardening and IASCC susceptibility. The work focused on commercial heats of 304 stainless steel (heat B) and 316 stainless steel (heat P). Irradiation with protons was conducted at 360 deg. C to doses between 0.3 and 5.0 dpa to approximate those by neutron irradiation at 275 deg. C over the same dose range. Characterization consisted of grain boundary microchemistry, dislocation loop microstructure, hardness as well as stress corrosion cracking (SCC) susceptibility of both un-irradiated and irradiated samples in oxygenated and de-oxygenated water environments at 288 deg. C. Overall, microchemistry, microstructure, hardening and SCC behavior of proton- and neutron-irradiated samples were in excellent agreement. RIS analysis showed that in both heats and for both irradiating particles, the pre-existing grain boundary Cr enrichment transformed into a 'W' shaped profile at 1.0 dpa and then into a 'V' shaped profile between 3.0 and 5.0 dpa. Grain boundary segregation of Cr, Ni, Si, and Mo all followed the same trends and agreed well in magnitude. The microstructure of both proton- and neutron-irradiated samples was dominated by small, faulted dislocation loops. Loop size distributions were nearly identical in both heats over a range of doses. Saturated loop size following neutron irradiation was about 30% larger than that following proton irradiation. Loop density increased with dose through 5.0 dpa for both particle irradiations and was a factor of 3 greater in neutron-irradiated samples vs. proton-irradiated samples. Grain boundary

  8. Measurement of fission gases released by HTR irradiation samples in the BR 2 reactor (Mol/Belgium)

    International Nuclear Information System (INIS)

    Koetter, H.; Mueller, H.B.

    1975-04-01

    During the irradiation of HTR-test fuel (coated particles resp. compacts) the release rate of fission gases is measured automatically. For that purpose the γ-spectrum of the sweep gas is analyzed with respect to the isotopes Xe-133, Xe-135, Xe-135sup(m), Xe-137, Xe-138, Kr-85sup(m), Kr-87, Kr-88, Kr-89. Gas sampling, spectral analysis, data handling and evaluation are controlled by computer. (orig.) [de

  9. 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

  10. Ionic conductivity in irradiated KCL

    International Nuclear Information System (INIS)

    Vignolo Rubio, J.

    1979-01-01

    The ionic conductivity of X and gamma irradiated KCL single crystals has been studied between room temperature and 600 degree centigree. the radiation induced damage resulting in a decrease of the conductivity heals by thermal annealing in two steps which are at about 350 and 550 degree centigree respectively. It has been found that the radiation induced colour centres are not involved in the observed decrease of the ionic conductivity. However. It has been observed that the effects of quenching and plastic deformation on the conductivity of the samples are very similar to the effect induced by irradiation. It is suggested that, samples radiation induced dislocation loops might cause the ionic conductivity decrease observed in irradiated samples. (Author)

  11. Influence of high energy electron irradiation and gamma irradiation on the osmotic resistance of human erythrocyte membranes

    International Nuclear Information System (INIS)

    Catana, D.; Hategan, Alina; Moraru, Rodica; Popescu, Alina; Morariu, V. V.

    1998-01-01

    The effects of 5 MeV electrons and of gamma irradiation at 0 deg. C on the osmotic fragility of human erythrocyte membranes are presented. Both electron and gamma radiation in the range 0-400 Gy induced no hemolysis indicating that the membrane modifications due to radiation interaction do not reach a critical point as to cause swelling of the cells and subsequent lysis. The osmotic stress experiments performed after irradiation showed that the gamma irradiated erythrocytes exhibited an almost similar sigmoidal behavior for all irradiation doses, whereas the electron irradiated samples showed a much larger increase in hemolysis degree and, in the case of a given electron dose (100 Gy), the hemolysis was found much smaller than for the control sample (a similar behavior of the erythrocytes was found in the case of microwave irradiation at temperatures under 0 deg. C). Our experimental data suggest that electron radiation and gamma radiation have different impacts on the erythrocyte membrane fluidity, involving, probably, the different rate of energy deposition in the samples and the direct interaction of electrons with the erythrocyte membranes. (authors)

  12. EPR measurements in irradiated polyacetylene

    International Nuclear Information System (INIS)

    Hola, O.; Foeldesova, M.

    1990-01-01

    The influence of γ-irradiation on the paramagnetic properties of polyacetylene, and the dependence of the EPR spectra on the radiation dose in samples of irradiated polyacetylene were studied. The measurements show that no essential changes of the spin mobility occurred during irradiation. (author) 3 refs.; 2 figs

  13. Some physical properties of irradiated and non-irradiated oxide glasses containing uranium

    International Nuclear Information System (INIS)

    Simon, V.; Ardelean, I.; Simon, S.; Cozar, O.; Milea, I.; Lupsa, I.; Mih, V.

    1995-01-01

    The x U O 3 (1-x) [2 P 2 O 5 · Na 2 O] non-irradiated and gamma irradiated glasses (0 3+ , U 4+ and U 5+ ions. The gamma irradiation induces paramagnetic defects around the glass network forming sites occupied by phosphorous atoms. The non-irradiated samples are weak paramagnetic up to x = 0.1. For higher U O 3 concentration (0.1 < x ≤ 0.2) the magnetic measurements indicated a larger number of paramagnetic ions which are magnetically isolated and exhibit a Curie type behaviour. (author) 5 figs., 14 refs

  14. The effect of helium generation and irradiation temperature on tritium release from neutron irradiated beryllium

    International Nuclear Information System (INIS)

    Kupriyanov, I.B.; Gorokhov, V.A.; Vlasov, V.V.; Kovalev, A.M.; Chakin, V.P.

    2004-01-01

    The effect of neutron irradiation condition on tritium release from beryllium is described in this paper. Beryllium samples were irradiated in the SM reactor with neutron fluence (E > 0.1 MeV) of (0.37-2.0) x 10 22 cm -2 at 70-100degC and 650-700degC. Mass-spectrometer technique was used in out of tritium release experiments during stepped-temperature anneal within a temperature range from 250 to 1300degC. The total amount of helium accumulated in irradiated beryllium samples varied from 521 appm to 3061 appm. The first signs of tritium release were detected at temperature of 406-553degC. It was shown that irradiation temperature and helium generation level significantly affect the tritium release. A fraction of 44 - 74 % of tritium content in samples irradiated at low temperature (70 - 100degC) is release from beryllium at an annealing temperature below 800degC, whereas for samples after high temperature irradiation (650 - 700 degC) tritium release did not exceed 14 %. Majority of tritium (∼68%) is released within a temperature range from 800 to 920 degC. The increase of helium generation from 521 appm to 3061 appm results in lowering the temperature of maximal tritium release rate and the upper temperature of tritium release from beryllium by 100-130degC and 200-240degC, correspondingly. On the basis of data obtained, the diffusion coefficients of tritium in beryllium were calculated. (author)

  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. The Design of Sample Driver System for Gamma Irradiator Facility at Thermal Column of Kartini Reactor

    International Nuclear Information System (INIS)

    Suyamto; Tasih Mulyono; Setyo Atmojo

    2007-01-01

    The design and construction of sample driver system for gamma irradiator facility at thermal column of Kartini reactor post operation has been carried out. The design and construction is based on the space of thermal column and the sample speed rotation which has to as low as possible in order the irradiation process can be more homogeneity. The electrical and mechanical calculation was done after fixation the electrical motor and transmission system which will be applied. By the assumption that the maximum sample weight is 50 kg, the electric motor specification is decided due to its rating i.e. single phase induction motor, run capacitor type, 0.5 HP; 220 V; 3.61 A, CCW and CW, rotation speed 1430 rpm. To achieve the low load rotation speed, motor speed was reduced twice using the conical reduction gear with the reduction ratio 3.9 and thread reduction gear with the reduction ratio 60. From the calculation it is found that power of motor is 118.06 watt, speed rotation of load sample is 6.11 rpm due to the no load rotation of motor 1430 rpm. From the test by varying weight of load up to 75 kg it is known that the device can be operated in a good condition, both in the two direction with the average speed of motor 1486 rpm and load 6.3 rpm respectively. So that the slip is 0.268 % and 0.314 % for no load and full load condition. The difference input current to the motor during no load and full load condition is relative small i.e. 0.14 A. The safety factor of motor is 316 % which is correspond to the weight of load 158 kg. (author)

  17. Effect of electron irradiation on gas sensing properties of Al-Zno

    Directory of Open Access Journals (Sweden)

    Sunil C. Vattappalam

    2015-12-01

    Full Text Available Al–ZnO thin films are prepared by Silar method and are annealed at 450°C for 1 h. A selected number of samples are irradiated by high-energy electron beam and all are characterized by XRD, SEM and energy-dispersive X-ray spectroscopy. Both irradiated and non-irradiated samples are then placed independently inside a gas chamber kept at rotary vacuum. The gas chamber is maintained at a pressure of 0.20 mb and at a temperature of 350°C. Ethanol vapour is admitted in a controlled manner into the chamber and the resistance of the film is measured continuously before, during and after the admittance of the ethanol vapour. The experiment is repeated for different dosages of irradiation and different doping concentrations of Al and the resistance of the film getting reduced fast and considerably at the admittance of ethanol has been observed. The response and recovery time of the irradiated samples is compared with that of non-irradiated samples of the same doping concentration. It has been noted that both irradiated and non-irradiated samples show a response time of 1 s and recovery time of the irradiated samples is shorter than that of non-irradiated samples.

  18. Gamma-irradiation of wet corn. Microbiological aspects

    International Nuclear Information System (INIS)

    Poisson, Jeanne; Cahagnier, B.

    1973-01-01

    In the course of a survey of several years work on microbiological decontamination and control of wet corn by gamma-irradiation the following factors are studied: inhibiting and selective effect of gamma-irradiation (100 to 500krads) on the microflora of grains; evolution of residual microflora of irradiated wet grains (moisture content about 35%), during storage experiments under ventilated or airtight conditions. Two important points emerge from those studies. The microflora which develops on irradiated sample is much less varied than that of the control sample. The microbial population of an irradiated sample rises up in a few days on a level with the initial one of the control, then goes on increasing while remaining, as a rule, slightly inferior to that of the control placed under the same conditions. This greatly lowers the practical interest of irradiation, which can only be used together with another treatment able to inhibit the quick growth of the residual microflora [fr

  19. Modification of polycrystalline copper by proton irradiation

    International Nuclear Information System (INIS)

    Garcia S, F.; Cabral P, A.; Saniger B, J.M.; Banuelos, J.G.; Barragan V, A.

    1997-01-01

    Polished copper samples were irradiated with proton beams of 300 and 700 keV at room temperature and at -150 Centigrade. In this work the obtained results are reported when such copper irradiated samples are analysed with Sem, Tem, AFM. The Sem micrographs showed evident changes in surface of these copper samples, therefore an EDAX microanalysis was done for its characterization. additionally, the Tem micrographs showed heaps formation until 200 nm. Its electron diffraction spectra indicated that these heaps consist of a copper compound. Finally with AFM were observed changes in coloration of the irradiated sample surface, as well as changes in texture and rugosity of them. These results show in general that irradiation process with protons which is known as an innocuo process produces changes in the copper properties. (Author)

  20. Detection of irradiation treatment of foods using DNA 'comet assay'

    International Nuclear Information System (INIS)

    Khan, Hasan M.; Delincee, Henry

    1998-01-01

    Microgel electrophoresis of single cells (DNA comet assay) has been investigated to detect irradiation treatment of some food samples. These samples of fresh and frozen rainbow trout, red lentil, gram and sliced almonds were irradiated to 1 or 2 kGy using 10 MeV electron beam from a linear accelerator. Rainbow trout samples yielded good results with samples irradiated to 1 or 2 kGy showing fragmentation of DNA and, therefore, longer comets with no intact cells. Unirradiated samples showed shorter comets with a significant number of intact cells. For rainbow trout stored in a freezer for 11 days the irradiated samples can still be discerned by electrophoresis from unirradiated samples, however, the unirradiated trouts also showed some longer comets besides some intact cells. Radiation treatment of red lentils can also be detected by this method, i.e. no intact cells in 1 or 2 kGy irradiated samples and shorter comets and some intact cells in unirradiated samples. However, the results for gram and sliced almond samples were not satisfactory since some intact DNA cells were observed in irradiated samples as well. Probably, incomplete lysis has led to these deviating results

  1. Study of damages by neutron irradiation in lithium aluminates

    International Nuclear Information System (INIS)

    Palacios G, O.

    1999-01-01

    Lithium aluminates proposed to the production of tritium in fusion nuclear reactors, due to the thermal stability that they present as well as the behavior of the aluminium to the irradiation. As a neutron flux with profile (≅ 14 Mev) of a fusion reactor is not available. A irradiation experiment was designed in order to know the micro and nano structure damages produced by fast and thermal neutrons in two irradiation positions of the fusion nuclear reactor Triga Mark III: CT (Thermal Column) and SIFCA (System of Irradiation Fixed of Capsules). In this work samples of lithium aluminate were characterized by XRD (X-Ray Diffraction), TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy). Two samples were prepared by two methods: a) coalition method and b) peroxide method. This characterization comprised original and irradiated samples. The irradiated sample amounted to 4 in total: one for each preparation method and one for each irradiation position. The object of this analysis was to correlate with the received neutron dose the damages suffered by the samples with the neutron irradiation during long periods (440 H), in their micro and nano structure aspects; in order to understand the changes as a function of the irradiation zone (with thermal and fast neutron flux) and the preparation methods of the samples and having as an antecedent the irradiation in SIFCA position by short times (2h). The obtained results are referred to the stability of γ -aluminate phase, under given conditions of irradiation and defined nano structure arrangement. They also refer to the proposals of growth mechanism and nucleation of new phases. The error associated with the measurement of neutron dose is also discussed. (Author)

  2. Detection of Irradiated Tubers (Ginger and Potato) Using Photostimulated Luminescence Technique (PSL)

    International Nuclear Information System (INIS)

    Ros Anita Ahmad Ramli; Zainon Othman; Wan Saffiey Wan Abdullah; Foziah Ali; Zainab Harun

    2016-01-01

    Photo-stimulated luminescence (PSL) measurement was conducted to detect irradiated gingers (Zingiber officinale Roscoe) and potatoes (Solanum tuberosum) after dark storage for 1 week, 3 and 6 months. Using screening and calibrated PSL, all the samples were correctly distinguished between non-irradiated and irradiated samples at doses 50, 150 and 500 Gy based on photon count values. The PSL signal stability of irradiated samples (150 and 500 Gy) appeared to fade upon 6 months storage but remained well above upper threshold values of 5000 photon counts/ 60 s (PCs) for irradiated gingers and potatoes. The PCs of irradiated tubers showed a general trend of increase with the increase in doses up to 500 Gy. Samples showed highest intensity after irradiation. The differences in intensity to irradiation are possibly attributed to the varying quantity and quality of silicate minerals present in each tuber sample. Tubers irradiated at doses higher than 150 Gy, showed sensitivity index ratio of less than 10. Sensitivity Index was suggested for irradiated samples at doses slightly above 150 Gy. Irradiated samples at doses less than 150 Gy should be subjected for further investigation using thermoluminescence (TL) analysis. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated tubers. (author)

  3. Identifying irradiated flours by photo-stimulated luminescence technique

    Energy Technology Data Exchange (ETDEWEB)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi [Faculty of Science and Technology, National University of Malaysia, Bangi, 43000 Kajang, Selangor (Malaysia); Othman, Zainon; Abdullah, Wan Saffiey Wan [Malaysian Nuclear Agency, Bangi 43000 Kajang, Selangor (Malaysia)

    2014-02-12

    Photo-stimulated luminescence (PSL) technique was used in this study to detect gamma irradiation treatment of five types of flours (corn, rice, tapioca, wheat and glutinous rice) at four different doses 0, 0.2, .05 and 1kGy. The signal level was compared with two threshold values (700 and 5000). With the exception of glutinous rice, all irradiated samples produced a strong signal above the upper threshold (5000 counts/60s). All control samples produced negative result with the signals below the lower threshold (700 counts/60s) suggesting that the samples have not been irradiated. Irradiated glutinous rice samples produced intermediate signals (700 - 5000 counts/60s) which were subsequently confirmed using calibrated PSL. The PSL signals remained stable after 90 days of storage. The findings of this study will be useful to facilitate control of food irradiation application in Malaysia.

  4. Identifying irradiated flours by photo-stimulated luminescence technique

    International Nuclear Information System (INIS)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon; Abdullah, Wan Saffiey Wan

    2014-01-01

    Photo-stimulated luminescence (PSL) technique was used in this study to detect gamma irradiation treatment of five types of flours (corn, rice, tapioca, wheat and glutinous rice) at four different doses 0, 0.2, .05 and 1kGy. The signal level was compared with two threshold values (700 and 5000). With the exception of glutinous rice, all irradiated samples produced a strong signal above the upper threshold (5000 counts/60s). All control samples produced negative result with the signals below the lower threshold (700 counts/60s) suggesting that the samples have not been irradiated. Irradiated glutinous rice samples produced intermediate signals (700 - 5000 counts/60s) which were subsequently confirmed using calibrated PSL. The PSL signals remained stable after 90 days of storage. The findings of this study will be useful to facilitate control of food irradiation application in Malaysia

  5. Study on irradiation treatment to drunk crab

    International Nuclear Information System (INIS)

    Cao Hong; Chen Xiulan; Zhai Jianqing; Bao Jianzhong; Wang Jinrong

    2002-01-01

    For guaranteeing the quality of irradiated drunk crab, manufacture method of the dosimeter, sample setting and taking position, irradiation time, asymmetry degree of irradiation dose, contrast of the dosimeter are discussed and some reference datum to commercialization of drunk crab's irradiation are provided

  6. Effect of irradiation spectrum on the microstructure of ion-irradiated Al2O3

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1994-01-01

    Polycrystalline samples of alpha-alumina have been irradiated with various ions ranging from 3.6 MeV Fe + to 1 MeV H + ions at 650 C. Cross-section transmission electron microscopy was used to investigate the depth-dependent microstructure of the irradiated specimens. The microstructure following irradiation was observed to be dependent on the irradiation spectrum. In particular, defect cluster nucleation was effectively suppressed in specimens irradiated with light ions such as 1 MeV H + ions. On the other hand, light ion irradiation tended to accelerate the growth rate of dislocation loops. The microstructural observations are discussed in terms of ionization enhanced diffusion processes

  7. Influence of irradiation conditions on the gamma irradiation effect in polyethylene

    International Nuclear Information System (INIS)

    Kacarevic-Popovic, Z.; Gal, O.; Novakovic, L.J.; Secerov, B.

    2002-01-01

    Complete text of publication follows. The radiation cross-linking of polyethylene, due to its high cross-linking yield, has resulted in the radiation technology that has found application in radiation production of heat shrinkable structures and in improvement of mechanical and thermo-physical properties of oriented polyethylene objects. It is observed that the cross-linking efficiency decreases when the irradiation is carried out in the presence of oxygen. In order to estimate the conditions that improve cross-linking efficiency, gamma irradiation effect in two types of polyethylene, irradiated in water and air was investigated. The polyethylene samples used were the low density (LDPE) Lotrene CdF 0302 with 45% crystallinity and the high density (HDPE) Hiplex EHM 6003 with 73% crystallinity. Both kinds of samples, fixed in the Pyrex glass tubes, were simultaneously irradiated with 60 Co gamma rays in distilled water and air, at a doses rate of 9,5 kGy/h (determined by the Fricke dosimeter) at room temperature. Radiation induced oxidative degradation was followed through oxygen containing group formation by the carbonyl group band (1720 cm -1 ) and transvinylene group formation by the band at 966 cm -1 in the infrared spectra. Cross-linking efficiency was determined by gel content using the procedure of the extraction in xylene. The monitored effects of gamma irradiation in water and air point to the conclusion that irradiation in water leads to the lower oxidative degradation and higher cross-linking compared with the effects measured after irradiation in air

  8. Radiation research of materials using irradiation capsules

    International Nuclear Information System (INIS)

    Chamrad, B.

    1976-01-01

    The methods are briefly characterized of radiation experiments on the WWR-S research reactor. The irradiation capsule installed in the reactor including the electronic instrumentation is described. Irradiated samples temperature is stabilized by an auxiliary heat source placed in the irradiation space. The electronic control equipment of the system is automated. In irradiation experiments, experimental and operating conditions are recorded by a digital measuring centre with electric typewriter and paper tape data recording and by an analog compensating recorder. The irradiation experiment control system controls irradiated sample temperature, the supply current size and the heating element temperature of the auxiliary stabilizing source, inert and technological pressures of the capsule atmosphere and the thermostat temperature of the thermocouple junctions. (O.K.)

  9. Citrus asymmetric somatic hybrids produced via fusion of gamma-irradiated and iodoacetamide-treated protoplasts Híbridos somáticos assimétricos de citros produzidos pela fusão de protoplastos irradiados e tratados com iodoacetamida

    Directory of Open Access Journals (Sweden)

    Claudine Maria de Bona

    2009-05-01

    Full Text Available The objective of this study was to produce citrus somatic asymmetric hybrids by fusing gamma-irradiated protoplasts with iodoacetamide-treated protoplasts. Protoplasts were isolated from embryogenic suspension cells of grapefruit (Citrus paradisi Macfad. cultivars Ruby Red and Flame, sweet oranges (C. sinensis Osbeck 'Itaboraí', 'Natal', Valencia', and 'Succari', from 'Satsuma' (C. unshiu Marcow. and 'Changsha' mandarin (C. reticulata Blanco and 'Murcott' tangor (C. reticulata x C. sinensis. Donor protoplasts were exposed to gamma rays and receptor protoplasts were treated with 3 mmol L-1 iodoacetamide (IOA, and then they were fused for asymmetric hybridization. Asymmetric embryos were germinated, and the resulting shoots were either grafted onto sour orange, rough lemon or 'Swingle' (C. paradisi x Poncirus trifoliata x 'Sunki' mandarin rootstock seedlings, or rooted after dipping their bases in indol-butyric acid (IBA solution. The products were later acclimatized to greenhouse conditions. Ploidy was analyzed by flow cytometry, and hybridity was confirmed by amplified fragment length polymorphism (AFLP analysis of plantlet DNAsamples. The best treatment was the donor-recipient fusion combination of 80 Gy-irradiated 'Ruby Red' protoplasts with 20 min IOA-treated 'Succari' protoplasts. Tetraploid and aneuploid plants were produced. Rooting recalcitrance was solved by dipping shoots' stems in 3,000 mg L-1 IBA solution for 10 min.O objetivo deste trabalho foi produzir híbridos somáticos assimétricos de citros pela fusão de protoplastos irradiados com raios gama e protoplastos tratados com iodoacetamida. Protoplastos foram isolados de suspensões celulares embriogênicas de pomelo (Citrus paradisi Macfad., cultivares Ruby Red e Flame, de laranja doce (C. sinensis Osbeck 'Itaboraí', 'Natal', Valencia' e 'Succari', de tangerinas 'Satsuma' (C. unshiu Marcow. e 'Changsha' (C. reticulata Blanco e de tangor 'Murcott' (C. reticulata x C. sinensis

  10. Post-factum detection of food irradiation

    International Nuclear Information System (INIS)

    Meier, W.

    1991-01-01

    Irradiation of food containing bones or shells can be detected with a high degree of certainty by means of ESR and by analysis of the volatile hydrocarbons or of the o-tyrosine. The last two methods are used for identification of irradiated pure meat samples. Detection of irradiation in spices and dried vegetables is possible with the thermoluminescence method and ESR, if non-irradiated control samples are available. These methods are being tested in the period 1990/1991 by an EC Commission-sponsored interlaboratory study of spices and food containing bones or shells, whereas the two chemical methods need further optimisation by work done in smaller working groups. (orig.) [de

  11. Investigations of X-ray irradiation of marine fish aboard

    International Nuclear Information System (INIS)

    Karnop, G.; Reinacher, E.; Antonacopoulos, N.; Meyer, V.

    1976-01-01

    Studies on X-ray irradiation of ocean perch, cod and coley (at doses of 50-150 krad) are described. The results show that irradiation within this dose range has no significant effect on the shelf-life of fish stored in ice. Although irradiation positively influenced bacteriological and chemical characteristics (e.g. reduction of total aerobic count, and inhibition of decomposition of N-containing compounds), the organoleptically-limited shelf-life of irradiated specimens was similar to that of non-irradiated specimens. Organoleptic changes in irradiated and in non-irradiated samples differed; this is attributed to the abnormal spoilage flora (mainly radiation-resistant Moraxella spp.) in the irradiated samples. (orig./HP) [de

  12. Evaluation of spaghetti prepared from irradiated and non-irradiated semolina flour, defatted soybean and wheat germ

    International Nuclear Information System (INIS)

    Nassef, A.E.; Assem, N.H.

    2005-01-01

    The aim of the present investigation was to produce spaghetti from semolina flour supplemented with 5, 7.5 and 10% wheat germ and 5, 7.5 and 10% defatted soybean flours and gamma irradiated at 5 and 10 KGy to improve its nutritive value. Part of the blend was left without irradiation to serve as control. All samples of spaghetti were analyzed for chemical composition, color, cooking properties, sensory evaluation and amino acids contents. The results of chemical composition showed high protein and fat contents by increasing the percentage of addition for wheat germ and defatted soybean, which irradiated and non-irradiated, in spaghetti. Sensory evaluation and cooking properties for spaghetti supplemented with 5 and 7.5% non-irradiated or irradiated (5 KGy) defatted soybean gave the best values comparing with supplementation by 10% non-irradiated and irradiated with 10 KGy. The best treatments, based on sensory evaluation results, were analyzed for amino acids. Essential and non-essential amino acid levels were found to be higher in samples supplemented with wheat germ and defatted soybean when compared with control, which was prepared from semolina only

  13. The importance of the sampling frequency in determining short-time-averaged irradiance and illuminance for rapidly changing cloud cover

    International Nuclear Information System (INIS)

    Delaunay, J.J.; Rommel, M.; Geisler, J.

    1994-01-01

    The sampling interval is an important parameter which must be chosen carefully, if measurements of the direct, global, and diffuse irradiance or illuminance are carried out to determine their averages over a given period. Using measurements from a day with rapidly moving clouds, we investigated the influence of the sampling interval on the uncertainly of the calculated 15-min averages. We conclude, for this averaging period, that the sampling interval should not exceed 60 s and 10 s for measurement of the diffuse and global components respectively, to reduce the influence of the sampling interval below 2%. For the direct component, even a 5 s sampling interval is too long to reach this influence level for days with extremely quickly changing insolation conditions. (author)

  14. New facility for post irradiation examination of neutron irradiated beryllium

    International Nuclear Information System (INIS)

    Ishitsuka, Etsuo; Kawamura, Hiroshi

    1995-01-01

    Beryllium is expected as a neutron multiplier and plasma facing materials in the fusion reactor, and the neutron irradiation data on properties of beryllium up to 800 degrees C need for the engineering design. The acquisition of data on the tritium behavior, swelling, thermal and mechanical properties are first priority in ITER design. Facility for the post irradiation examination of neutron irradiated beryllium was constructed in the hot laboratory of Japan Materials Testing Reactor to get the engineering design data mentioned above. This facility consist of the four glove boxes, dry air supplier, tritium monitoring and removal system, storage box of neutron irradiated samples. Beryllium handling are restricted by the amount of tritium;7.4 GBq/day and 60 Co;7.4 MBq/day

  15. Fungal evaluation on green tea irradiated with different water activities

    International Nuclear Information System (INIS)

    Fanaro, Gustavo B.; Duarte, Renato C.; Rodrigues, Flavio T.; Villavicencio, Anna Lucia C.H.; Correa, Benedito

    2011-01-01

    The aim of this study was evaluate the fungal contamination in green tea irradiated with different radiation doses and water activities. Samples were irradiated in 60 Co irradiator at doses of 0, 2.5, 5.0, 7.5 and 10.0kGy with three different water activities. In the sample with decreased water activity, the count of fungi was lower than others samples followed by original Aw and the samples with the higher water activity, however there is no difference between the increased and decreased water activities samples after the irradiation on fungi contamination at dose of 2.5 kGy. (author)

  16. Irradiation behaviors of coated fuel particles, (3)

    International Nuclear Information System (INIS)

    Fukuda, Kousaku; Kashimura, Satoru; Iwamoto, Kazumi; Ikawa, Katsuichi

    1980-07-01

    This report is concerning to the irradiation experiments of the coated fuel particles, which were performed by 72F-6A and 72F-7A capsules in JMTR. The coated particles referred to the preliminary design of VHTR were prepared for the experiments in 1972 and 1973. 72F-6A capsule was irradiated at G-10 hole of JMTR fuel zone for 2 reactor cycles, and 72F-7A capsule had been planned to be irradiated at the same irradiation hole before 72F-6A. However, due to slight leak of the gaseous fission products into the vacuum system controlling irradiation temperature, irradiation of 72F-7A capsule was ceased after 85 hrs since the beginning. In the post irradiation examination, inspection to surface appearance, ceramography, X-ray microradiography and acid leaching for the irradiated particle samples were made, and crushing strength of the two particle samples was measured. (author)

  17. Nicotine promotes rooting in leaf explants of in vitro raised seedlings of tomato, Lycopersicon esculentum Miller var. Pusa Ruby.

    Science.gov (United States)

    Bamel, Kiran; Gupta, Rajendra; Gupta, Shrish C

    2015-11-01

    Nicotine promotes rooting in leaf explants of tomato (Lycopersicon esculentum Miller var. Pusa Ruby). Nicotine at 10(-9) to 10(-3) M concentrations was added to the MS basal medium. The optimum response (three-fold increase in rooting) was obtained at 10(-7) M nicotine-enriched MS medium. At the same level i.e. 10(-7) M Nicotine induced dramatic increase (11-fold) in the number of secondary roots per root. We have shown earlier that exogenous acetylcholine induces a similar response in tomato leaves. Since nicotine is an agonist of one of the two acetylcholine receptors in animals, its ability to simulate ACh action in a plant system suggests the presence of the same molecular mechanism operative in both, animal and plant cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. 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)

  19. Effects of gamma irradiation on wheat quality

    International Nuclear Information System (INIS)

    Ozkaya, B.; Koksel, H.; Ozkaya, H.; Tutluer, H.

    1994-01-01

    Effect of gamma irradiation at the doses of 2.5,5.0,7.5,10.0 and 12.5 kGy on two bread wheat samples (Bezostaya and Gerek) with distinct physical and technological properties was investigated in this study.Irradiation at the levels used had no significant effect on the flour yields of both varieties.No apparent changes were observed in ash,protein and wet gluten contents of the irradiated samples and control.However,as the radiation level was increased the falling number and sedimentation values of the irradiated samples showed a steady decrease.Thiamine and riboflavin contents also decreased significantly with irradiation.Farinograph absorption increased with increasing radiation exposure.However, dough development time,stability and valorimeter values decreased as radiation levels increased.Maximum resistance to extension(Rm), resistance at constant deformation (R 5) and area(A) values of extensograms decreased in both varieties as radiation levels increased

  20. The detection of irradiated foods using the Direct Epifluorescent Filter Technique

    International Nuclear Information System (INIS)

    Betts, R.P.; Bankes, P.; Stringer, M.F.; Farr, L.

    1988-01-01

    A method was evaluated which has the potential to detect a food sample which has been irradiated. The technique will give an indication of the total number of viable micro-organisms present before irradiation. It is based on the comparison of an aerobic plate count (APC) with a count obtained using the Direct Epifluorescent Filter Technique (DEFT). When the APC of an irradiated sample was compared with the DEFT count on the same sample, the APC was considerably lower than that obtained by DEFT. The count of orange fluorescing cells after irradiation, however, correlated well with an APC of the same sample before irradiation. For the samples examined the DEFT count determined the viable microbial population in the sample before irradiation. The difference between the APC and the DEFT count gave the number of organisms rendered non-viable by the process. (author)

  1. Why the concern about irradiation as a food preservation technique?

    International Nuclear Information System (INIS)

    Anon

    2001-01-01

    Full text: Irradiation is a food preservation process that like the more traditional and alternative methods is intended to keep food safe to eat by delaying the natural decomposition processes that result from bacterial action. Preservation of foods by irradiation, although still not available in Australia, is readily accepted in some 44 countries, including France. This project is set up to examine if a sample of fresh fruits and vegetables, when irradiated to the recommended 'preservation' dose level, becomes 'radioactive'. By placing the 'irradiated' sample, together with an identical 'control' sample of the same fresh fruit and vegetables, in an x-radiography cassette in a shielded 'cave', differences in film 'blackening' over the exposure period would indicate relative radioactivity from within the respective samples. Also, using simultaneous daily photographs of both the 'irradiated' and non-irradiated 'control' samples, the delay of onset of visible decay of both can be determined

  2. DETECTION OF SOME IRRADIATED NUTS BY ELECTRON SPIN RESONANCE (ESR) TECHNIQUE

    Energy Technology Data Exchange (ETDEWEB)

    KHALLAF, M F; YASIN, N M.N. [Food Science Dept., Faculty of Agriculture, Ain Shams University, Cairo (Egypt); EL-NASHABY, F M; ALI, H G.M.; EL-SHIEMY, S M [Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt)

    2008-07-01

    The present investigation was carried out to establish the electron spin resonance (ESR) detection method for identifying irradiated nuts (almond and pistachio). Samples were irradiated with 2, 4 and 6 kGy and stored at room temperature (25{+-} 2{sup 0}C) for six months to study the possibility of detecting its previous irradiation treatments by ESR spectroscopy. Analysis was carried out just after irradiation treatment and during ambient storage period. The ESR signal intensities of irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation so, all irradiated samples under investigation could be differentiated from non-irradiated ones immediately after irradiation treatment. The decay in radicals responsible of ESR signals showed the identification of irradiated almond (shell or edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  3. DETECTION OF SOME IRRADIATED NUTS BY ELECTRON SPIN RESONANCE (ESR) TECHNIQUE

    International Nuclear Information System (INIS)

    KHALLAF, M.F.; YASIN, N.M.N.; EL-NASHABY, F.M.; ALI, H.G.M.; EL-SHIEMY, S.M.

    2008-01-01

    The present investigation was carried out to establish the electron spin resonance (ESR) detection method for identifying irradiated nuts (almond and pistachio). Samples were irradiated with 2, 4 and 6 kGy and stored at room temperature (25± 2 0 C) for six months to study the possibility of detecting its previous irradiation treatments by ESR spectroscopy. Analysis was carried out just after irradiation treatment and during ambient storage period. The ESR signal intensities of irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation so, all irradiated samples under investigation could be differentiated from non-irradiated ones immediately after irradiation treatment. The decay in radicals responsible of ESR signals showed the identification of irradiated almond (shell or edible part) and pistachio (edible part) was impossible after six months of ambient storage

  4. Import control of irradiated foods by the thermoluminescence method

    International Nuclear Information System (INIS)

    Pinnioja, S.; Autio, T.; Niemi, E.; Pensala, O.

    1993-01-01

    A thermoluminescence (TL) method was applied for the import control of irradiated foods. The method is based on the determination of the TL of mineral contaminants in foods. Detection of irradiation was incorporated in official Finnish control procedures in spring 1990. For foodstuffs with a reduced microbe content and in which no fumigant residues are found, possible irradiation is investigated by the TL method. The minerals are separated from the foods in different ways: picking is used for spices; water rinsing for herbs, spices, berries and mushrooms; high-density liquid to separate the organic material from the mineral fraction in seafood; and carbon tetrachloride for foods forming gels with water. To date about 140 food samples have been analysed for control purposes: 50 samples of herbs and spices, 25 samples of berries and mushrooms and 65 samples of seafood. Of these, 14 samples of herbs and spices and 5 samples of seafood were shown to have been irradiated. Differences in TL intensity between irradiated and unirradiated samples were at least 1 and usually 3-4 orders of magnitude. (orig.)

  5. Comparison of deuterium retention for ion-irradiated and neutron-irradiated tungsten

    International Nuclear Information System (INIS)

    Oya, Yasuhisa; Kobayashi, Makoto; Okuno, Kenji; Shimada, Masashi; Calderoni, Pattrick; Oda, Takuji; Hara, Masanori; Hatano, Yuji; Watanabe, Hideo

    2014-01-01

    The behavior of D retentions for Fe 2+ irradiated tungsten with the damage of 0.025-3 dpa was compared with that for neutron irradiated tungsten with 0.025 dpa. The D 2 TDS spectra for Fe 2+ irradiated tungsten consisted of two desorption stages at 450 K and 550 K although that for neutron irradiated tungsten was composed of three stages and addition desorption stage was found around 750 K. The desorption rate of major desorption stage at 550 K increased as the number of dpa by Fe 2+ irradiation increased. In addition, the first desorption stage at 450 K was only found for the damaged samples, indicating that the second stage would be based on intrinsic defects or vacancy produced by Fe 2+ irradiation and the first stage should be the accumulation of D in mono vacancy leading to the lower activation energy, where the dislocation loop and vacancy was produced. The third one was only found for the neutron irradiation, showing the D trapping by void or vacancy cluster and the diffusion effect is also contributed due to high FWHM of TDS spectrum. It can be said that the D 2 TDS spectra for Fe 2+ -irradiated tungsten could not represent that for neutron-irradiated one, showing that the deuterium trapping and desorption mechanism for neutron-irradiated tungsten has a difference from that for ion-irradiated one. (author)

  6. Treatment of tannery effluent by irradiation. [gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Roszak, W; Pekala, W

    1983-01-01

    Different samples of tannins were exposed to gamma radiation at room temperature. Some of them were aerated during irradiation.In irradiated samples the concentration of phenol and organic substances decreased and their biodegradability increased. Aerated samples had a higher decrease of phenol concentration. (E.G.M.).

  7. Studies on some irradiated food products

    International Nuclear Information System (INIS)

    Mohammed, H.M.B.

    1998-01-01

    The aim of this investigation was to study the possibility of using some doses of gamma irradiation and cold storage (4+1 C) for improving the hygienic quality and shelf-life of some meat products ( beef luncheon, processed minced beef and fresh beef sausage). luncheon meat samples were irradiated at doses of 4,6,8,10 and 12 k Gy, while beef and sausage samples were subjected to 4,6 and 8 KGy gamma rays doses and the effects of irradiation on the organoleptic properties, microbiological aspects and the chemical composition were studied during cold storage (4+1 C) of samples. Attention was focussed on the changes occurred in the organoleptic properties of these products by the evaluation of sensory scores for appearance, color and odor of samples post irradiation and during cold storage (4+1 C). In addition, the effects of treatments and cold storage on the microbiological quality by the determination of total bacterial count, total psychropilic bacteria, total coliforms, total molds and yeasts, staphylococcus aureus, streptococcus faecalis as well as the detection of salmonellae were studied

  8. Heavy Ion Irradiation Effects in Zirconium Nitride

    International Nuclear Information System (INIS)

    Egeland, G.W.; Bond, G.M.; Valdez, J.A.; Swadener, J.G.; McClellan, K.J.; Maloy, S.A.; Sickafus, K.E.; Oliver, B.

    2004-01-01

    Polycrystalline zirconium nitride (ZrN) samples were irradiated with He + , Kr ++ , and Xe ++ ions to high (>1.10 16 ions/cm 2 ) fluences at ∼100 K. Following ion irradiation, transmission electron microscopy (TEM) and grazing incidence X-ray diffraction (GIXRD) were used to analyze the microstructure and crystal structure of the post-irradiated material. For ion doses equivalent to approximately 200 displacements per atom (dpa), ZrN was found to resist any amorphization transformation, based on TEM observations. At very high displacement damage doses, GIXRD measurements revealed tetragonal splitting of some of the diffraction maxima (maxima which are associated with cubic ZrN prior to irradiation). In addition to TEM and GIXRD, mechanical property changes were characterized using nano-indentation. Nano-indentation revealed no change in elastic modulus of ZrN with increasing ion dose, while the hardness of the irradiated ZrN was found to increase significantly with ion dose. Finally, He + ion implanted ZrN samples were annealed to examine He gas retention properties of ZrN as a function of annealing temperature. He gas release was measured using a residual gas analysis (RGA) spectrometer. RGA measurements were performed on He-implanted ZrN samples and on ZrN samples that had also been irradiated with Xe ++ ions, in order to introduce high levels of displacive radiation damage into the matrix. He evolution studies revealed that ZrN samples with high levels of displacement damage due to Xe implantation, show a lower temperature threshold for He release than do pristine ZrN samples. (authors)

  9. Preservation of Minced Meats by Using Medium and High-doses Irradiation

    International Nuclear Information System (INIS)

    Hammad, A.A.I.; Swailam, H.M.H.; Taha, S.M.A.

    2003-01-01

    The effect of medium (2.5-10 kGy) dose irradiation and high(20-70 kGy) dose irradiation on the microbiological, chemical and organoleptic properties of minced meat samples was studied. It was found that irradiation dose of only 5 kGy greatly reduced all microbial counts and completely eliminated all non-spore forming pathogenic bacteria contaminated minced meat samples. Consequently this irradiation dose extended the refrigerated (3 degree ±1) storage life of these products for more than 8 weeks. This irradiation dose almost did not affect the chemical composition, particularly the main amino acids and main fatty acids of minced meat samples. Panelists could not differentiate between irradiated minced meat samples at this dose and unirradiated samples. High doses irradiation, i.e.40 and 70 kGy were sufficient and efficient in sterilization of minced meat samples and in obtaining long-stable minced meat products (Two years) at ambient temperature. These irradiation doses slightly reduced (not more than 7%) aspartic acid, glutamic acid, methionine and lysine of minced meat. It also decreased the relative percentage of total unsaturated fatty acids by not more than 17 % . These high irradiation doses caused loss of C 18:3 and C 20:1

  10. Calibrated photostimulated luminescence is an effective approach to identify irradiated orange during storage

    International Nuclear Information System (INIS)

    Jo, Yunhee; Sanyal, Bhaskar; Chung, Namhyeok; Lee, Hyun-Gyu; Park, Yunji; Park, Hae-Jun; Kwon, Joong-Ho

    2015-01-01

    Photostimulated luminescence (PSL) has been employed as a fast screening method for various irradiated foods. In this study the potential use of PSL was evaluated to identify oranges irradiated with gamma ray, electron beam and X-ray (0–2 kGy) and stored under different conditions for 6 weeks. The effects of light conditions (natural light, artificial light, and dark) and storage temperatures (4 and 20 °C) on PSL photon counts (PCs) during post-irradiation periods were studied. Non-irradiated samples always showed negative values of PCs, while irradiated oranges exhibited intermediate results after first PSL measurements. However, the irradiated samples had much higher PCs. The PCs of all the samples declined as the storage time increased. Calibrated second PSL measurements showed PSL ratio <10 for the irradiated samples after 3 weeks of irradiation confirming their irradiation status in all the storage conditions. Calibrated PSL and sample storage in dark at 4 °C were found out to be most suitable approaches to identify irradiated oranges during storage. - Highlights: • Photostimulatedluminescence (PSL) was studied to identify irradiated orange for quarantine application. • PSL detection efficiency was compared amonggamma,electron, and X irradiation during shelf-life of oranges • PSL properties of samples were characterized by standard samples • Calibrated PSL gave a clear verdict on irradiation extending potential of PSL technique

  11. Microbiological decontamination of some herbs by irradiation

    International Nuclear Information System (INIS)

    Migdal, W.; Owczarczyk, H.B.

    1996-01-01

    The research work on the microbiological decontamination of the medical herbs by electron beam was carried out. The seven samples of the herbs granules were irradiated at the doses 3, 6 and 10 kGy. It has been shown, that D10 values are varied in several samples after irradiation. Additional, research work, by gas chromatographic method, on the composition volatile oils (salvia, orange, peppermint and anise), after irradiation at the dose 4.4 and 8.8 kGy was carried out. It was not significant differences in the compositions between control and irradiated oils. (author). 12 figs, 2 tabs

  12. Microbiological and chemical characteristics of gamma irradiated roasted Veal Meat

    International Nuclear Information System (INIS)

    Aftfy, S.A.; Abdel-Daiem, M.H.

    2007-01-01

    This investigation aims 10 study the possibility of using gamma irradiation at doses of 1,3 and 5 KGy for microbial decontamination of roasted veal meat (kebab). The samples were purchased from local market and examined for the counts of Staphylococcus aureus, Bacillus cereus, presence of Salmonella spp and the counts of total bacterial, molds and yeasts and Enterobacteriaceae. The results illustrated that all samples were positive for Staphylococcus aureus, Bacillus cereus, while Salmonella spp was detected in only 3 samples. Therefore, these product samples were gamma irradiated at doses of 0,1,3 and 5 kGy, then stored at cold storage (4±1 degree C). The effects of these treatments on the microbiological, chemical and sensory characteristics were studied post treatment and during cold storage. Irradiation at 1 kGy reduced the counts of total bacterial, molds and yeasts, Enterobacteriaceae, Staphylococcus aureus and Bacillus cereus as well as eliminating Salmonella spp. On the other hand, irradiation at 3 and 5 kGy doses completely eliminated the present Enterobacteriaceae, S. aureus, B, cereus and Salmonella spp. Irradiation of samples increased their amounts of thiobarbituric acid reactive substances (TBARS) but it did not affect the sensory characteristics of samples and it had no effects on their total volatile nitrogen (TVN) contents, while storage increased the TBARS and TVN for irradiated and non-irradiated samples. Gamma irradiation treatments had no effects on the sensory characteristics for appearance, odor and taste of all kebab samples and extended their time of sensory preference. However, doses of 1, 3 and 5 kGy reduced the counts of total bacteria and extended of the refrigerated shelf-life of samples to 11, 23 and 29 days, respectively, compared to 5 days for non-irradiated controls

  13. Improvement of microbiological qualities of namphrik by gamma irradiation

    Science.gov (United States)

    Chahorm, K.; Neramitmansook, N.; Kongsang, N.; Ko, J.

    2017-06-01

    Twenty samples of Namphrik from commercial markets were evaluated the microbiological qualities. It was found that 15 samples did not meet Thai Community Product Standard. The total plate count (TPC) in 15 samples were higher than the maximum limits (1.60x104 - 4.4x105 CFU/g). In addition, the other pathogens were higher than the maximum limits such as B. cereus in 11 samples (2.10x103 - 6.10x104 CFU/g) S. aureus in 2 samples (15 - 40 CFU/g) Clostridium perfringens in 4 samples (1.00x102 - 8.8x103 CFU/g) and yeast&mold in 9 samples (3.00 x102 - 9.00x103 CFU/g). To reduce TPC and pathogenic bacteria, the gamma irradiation were applied at 3.28- 4.43 kGy. The results indicated that the irradiation can reduce the TPC around 1.2 - 3.9 log cycles and eliminate pathogens bacteria in the product to make all of 15 samples qualified to the standard. The sensory evaluation was conducted in Namphrik Narok by using difference from control test to determine whether the consumers can differentiate between the non-irradiated and irradiated. The result showed that the consumers can significantly differentiate the color, odor and flavor (p0.05. Both non-irradiated and irradiated were scored at 6.4 (slightly to moderately preference). Thus the gamma irradiation can be used as a tool to improve the microbiological qualities of the Namphrik Narok product without effecting the consumer preference.

  14. Double use of focused microwave irradiation for accelerated matrix hydrolysis and lipid extraction in milk samples

    International Nuclear Information System (INIS)

    Garcia-Ayuso, L.E.; Luque de Castro, M.D.; Velasco, J.; Dobarganes, M.C.

    1999-01-01

    Irradiation with microwave energy has allowed to carry out the extraction of lipids from milk samples (namely, cow, goat and sheep) with quantitative results similar to the Weibull–Berntrop extraction procedure but milk fat obtained by microwave assisted extraction undergoes lesser chemical transformation of triglycerides during the whole process. A considerable reduction of the procedure time (50 min versus 10 h) is achieved with similar reproducibility to that provided by the conventional method. An in situ’ solvent recycling step makes the method environmentally clean

  15. Fungal evaluation on green tea irradiated with different water activities

    Energy Technology Data Exchange (ETDEWEB)

    Fanaro, Gustavo B.; Duarte, Renato C.; Rodrigues, Flavio T.; Villavicencio, Anna Lucia C.H., E-mail: gbfanaro@ipen.b, E-mail: villavic@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (CTR/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes; Correa, Benedito, E-mail: correabe@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Ciencias Biologicas. Dept. de Micologia

    2011-07-01

    The aim of this study was evaluate the fungal contamination in green tea irradiated with different radiation doses and water activities. Samples were irradiated in {sup 60}Co irradiator at doses of 0, 2.5, 5.0, 7.5 and 10.0kGy with three different water activities. In the sample with decreased water activity, the count of fungi was lower than others samples followed by original Aw and the samples with the higher water activity, however there is no difference between the increased and decreased water activities samples after the irradiation on fungi contamination at dose of 2.5 kGy. (author)

  16. Application of photostimulated luminescence (PSL) to detect irradiated molluscs

    International Nuclear Information System (INIS)

    Marchesani, G.; Chiaravalle, A.E.; Chiesa, L.M.

    2011-01-01

    Complete text of publication follows. In contrast to thermally processed foods, irradiation is a cold treatment both to reduce microbiological contamination and to increase the shelf-life of raw seafood. According to the list of States' authorizations molluscs can be irradiated in a range of 0.5 / 3 kGy only in authorized countries (e.g. UK, Belgium and Czech Republic). Therefore the aim of this study is to identify, at different dose levels (0.5, 1, 1.5, 2, 3 kGy), irradiated oysters, clams and mussels using luminescence materials from different sites (shells and pulps) and to determine sample sensitivity for previous screening result confirmation. A total number of 10 samples for each species were analyzed by both procedures: screening and calibrated PSL. Samples were irradiated using a low energy X-ray irradiator (RS-2400, Radsource Inc.) with the following operational settings: 150 kV and 45 mA. Whole pulps were simply dispensed into a clean Petri-dish whereas shells powder required to be fixed as a thick layer with silicone grease. Results obtained showed that screening analysis can be used to identify correctly all irradiated and non irradiated samples. Particularly untreated sample exhibited a sensitivity index from 2 to 4 order of magnitude greater than the exposed sample one, while for exposed specimen calibrated PSL signals, after re-irradiation at defined dose, were of the same order of the first measurement (initial PSL counts). In conclusion mineral debris contaminating pulps and biocarbonates from shells can be considered reliable radioinduced markers and PSL techniques can be easily applied for rapid and simple analysis to identify irradiated molluscs in official controls.

  17. Ion Irradiation Damage in Zirconate and Titanate Ceramics for Pu Disposition

    International Nuclear Information System (INIS)

    Stewart, Martin W.; Begg, Bruce D.; Finnie, K.; Colella, Michael; Li, H.; McLeod, Terry; Smith, Katherine L.; Zhang, Zhaoming; Weber, William J.; Thevuthasan, Suntharampillai

    2004-01-01

    In this paper, we discuss the effect of ion irradiation on pyrochlore-rich titanate and defect-fluorite zirconate ceramics designed for plutonium immobilization. Samples, with Ce as an analogue for Pu, were made via oxide routes and consolidated by cold-pressing and sintering. Ion irradiation damage was carried out with 2 MeV Au2+ ions to a fluence of 5 ions nm-2 in the accelerator facilities within the Environmental Molecular Sciences Laboratory at Pacific Northwest National Laboratory. Irradiated and non-irradiated samples were examined by x-ray diffraction, scanning and transmission electron microscopy, x-ray photoelectron and infrared spectroscopy, and spectroscopic ellipsometry. Samples underwent accelerated leach testing at pH 1.75 (nitric acid) at 90 C for 28 days. The zirconate samples were more ion-irradiation damage resistant than the titanate samples, showing little change after ion-irradiation whereas the titanate samples formed an amorphous surface layer ∼ 500 nm thick. While all samples had high aqueous durability, the titanate leach rate was ∼ 5 times that of the zirconate. The ion-irradiation increased the leach rate of the titanate without impurities by ∼ 5 times. The difference in the leach rates between irradiated and unirradiated zirconate samples is small. However, the zirconates were less able to incorporate impurities than the titanate ceramics and required higher sintering temperatures, ∼ 1500 C compared to 1350 C for the titanates.

  18. Improvement of physical properties of soyabeans by gamma irradiation

    International Nuclear Information System (INIS)

    Byun, M.-W.; Kwon, J.-H.; Mori, Tomohiko

    1993-01-01

    Physical properties of gamma-irradiated soybeans were evaluated at different temperatures by determining water absorption pattern and cooking characteristics of the sample. Irradiation at 2.5-10 kGy caused the reduction of soaking time in soybeans by 2-5 hours and the increase of hydration capacity by 10-20%, respectively, compared to the non-irradiated control at 20 o C. The activation energy for water absorption was lower in irradiated soybeans than in the non-irradiated control. Irradiation at 2.5-10 kGy caused the reduction of cooking time in soybeans by 30-60% compared to the non-irradiated control and the cooking rate constant of irradiated samples was higher about 2 times than that of the non-irradiated control. The irradiation efficacy on physical quality improvement was also recognized in the stored soybeans for one year at room temperature. (author)

  19. A germination test: an easy approach to know the irradiation

    International Nuclear Information System (INIS)

    Khawar, A.; Bhatti, I.A.; Bhatti, H.N.

    2010-01-01

    Food irradiation is an evolving preserving technique that provides a shield against the spoilage and might have a potential to ensure the food safety and security world wide. In the present study, feasibility to apply germination test to distinguish an un-irradiated and irradiated samples of wheat, maize, chickpea and black eye beans was checked. Samples were irradiated to the absorbed doses ranging from 0-10 kGy using Co-60 gamma irradiator and were germinated in plant growth chamber. Root and shoot lengths were measured at 7th day after gamma radiation treatment. In all the irradiated samples root and shoot lengths were decreased with the increase in radiation absorbed doses. The seeds irradiated to the absorbed doses more than 2 kGy were not germinated. Germination test proved as an easy and simple method to detect irradiation in wheat, maize, chickpea and black eye beans irradiated even at low absorbed doses. (author)

  20. Determination of 2-alkylcyclobutanones in ultraviolet light-irradiated fatty acids, triglycerides, corn oil, and pork samples: Identifying a new source of 2-alkylcyclobutanones.

    Science.gov (United States)

    Meng, Xiangpeng; Chan, Wan

    2017-02-15

    Previous studies have established that 2-alkylcyclobutanones (2-ACBs) are unique radiolytic products in lipid-containing foods that could only be formed through exposure to ionizing radiation, but not by any other means of physical/heat treatment methods. Therefore, 2-ACBs are currently the marker molecules required by the European Committee for Standardization to be used to identify foods irradiated with ionizing irradiation. Using a spectrum of state-of-the-art analytical instruments, we present in this study for the first time that the generation of 2-ACBs was also possible when fatty acids and triglycerides are exposed to a non-ionizing, short-wavelength ultraviolet (UV-C) light source. An irradiation dosage-dependent formation of 2-ACBs was also observed in UV-C irradiated fatty acids, triglycerides, corn oil, and pork samples. With UV-C irradiation becoming an increasingly common food treatment procedure, it is anticipated that the results from this study will alert food scientists and regulatory officials to a potential new source for 2-ACBs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Stress corrosion testing of irradiated cladding tubes

    International Nuclear Information System (INIS)

    Lunde, L.; Olshausen, K.D.

    1980-01-01

    Samples from two fuel rods with different cladding have been stress corrosion tested by closed-end argon-iodine pressurization at 320 0 C. The fuel rods with stress relieved and recrystallized Zircaloy-2 had received burnups of 10.000 and 20.000 MWd/ton UO 2 , respectively. It was found that the SCC failure stress was unchanged or slightly higher for the irradiated than for the unirradiated control tubes. The tubes failed consistently in the end with the lowest irradiation dose. The diameter increase of the irradiated cladding during the test was 1.1% for the stress-relieved samples and 0.24% for the recrystallized samples. SEM examination revealed no major differences between irradiated and unirradiated cladding. A ''semi-ductile'' fracture zone in recrystallized material is described in some detail. (author)

  2. Color, flavor, and sensory characteristics of gamma-irradiated salted and fermented anchovy sauce[Gamma irradiation; Fermented anchovy; Color; Flavor compounds; Electronic nose; Sensory evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H.; Ahn, Hyun Joo; Yook, Hong Sun; Kim, Kyong Soo; Rhee, Moon Soo; Ryu, Gi Hyung; Byun, Myung Woo E-mail: mwbyun@kaeri.re.kr

    2004-02-01

    Color, flavor, and sensory characteristics of irradiated salted and fermented anchovy sauce were investigated. The filtrate of salted and fermented anchovy was irradiated at 0, 2.5, 5, 7.5, and 10 kGy. After irradiation, Hunter's color values were increased, however, the color values were gradually decreased in all samples during storage. Amount of the aldehydes, esters, ketones, S-containing compounds, and the other groups were increased up to 7.5 kGy irradiation, then decreased at 10 kGy (P<0.05), while the alcohols and furan groups were increased by irradiation. Different odor patterns were observed among samples using electronic nose system analysis. Gamma-irradiated samples showed better sensory score and the quality was sustained during storage. In conclusion, gamma irradiation of salted and fermented anchovy sauce could improve its sensory quality by reducing typical fishy smell.

  3. Effect of high-dose irradiation on quality characteristics of ready-to-eat chicken breast

    International Nuclear Information System (INIS)

    Yun, Hyejeong; Haeng Lee, Kyung; Jung Lee, Hyun; Woon Lee, Ju; Uk Ahn, Dong; Jo, Cheorun

    2012-01-01

    High-dose (higher than 30 kGy) irradiation has been used to sterilize specific-purposed foods for safe and long-term storage. The objective of this study was to investigate the effect of high-dose irradiation on the quality characteristics of ready-to-eat chicken breast in comparison with those of the low-dose irradiation. Ready-to-eat chicken breast was manufactured, vacuum-packaged, and irradiated at 0, 5, and 40 kGy. The populations of total aerobic bacteria were 4.75 and 2.26 Log CFU/g in the samples irradiated at 0 and 5 kGy, respectively. However, no viable cells were detected in the samples irradiated at 40 kGy. On day 10, bacteria were not detected in the samples irradiated at 40 kGy but the number of bacteria in the samples irradiated at 5 kGy was increased. The pH at day 0 was higher in the samples irradiated at 40 kGy than those at 0 and 5 kGy. The 2-thiobarbituric acid reactive substance (TBARS) values of the samples were not significantly different on day 0. However, on day 10, the TBARS value was significantly higher in the samples irradiated at 40 kGy than those at 0 and 5 kGy. There was no difference in the sensory scores of the samples, except for off-flavor, which was stronger in samples irradiated at 5 and 40 kGy than control. However, no difference in off-flavor between the irradiated ones was observed. After 10 days of storage, only the samples irradiated at 40 kGy showed higher off-flavor score. SPME-GC–MS analysis revealed that 5 kGy of irradiation produced 2-methylbutanal and 3-methylbutanal, which were not present in the control, whereas 40 kGy of irradiation produced hexane, heptane, pentanal, dimethly disulfide, heptanal, and nonanal, which were not detected in the control or the samples irradiated at 5 kGy. However, the amount of compounds such as allyl sulfide and diallyl disulfide decreased significantly in the samples irradiated at 5 kGy and 40 kGy. - Highlights: ► Comparison of high (40 kGy) and low-dose irradiation (5 kGy) on

  4. Irradiation treatment of minimally processed carrots for ensuring microbiological safety

    Energy Technology Data Exchange (ETDEWEB)

    Ashraf Chaudry, Muhammad; Bibi, Nizakat; Khan, Misal; Khan, Maazullah; Badshah, Amal; Jamil Qureshi, Muhammad

    2004-10-01

    Minimally processed fruits and vegetables are very common in developed countries and are gaining popularity in developing countries due to their convenience and freshness. However, minimally processing may result in undesirable changes in colour, taste and appearance due to the transfer of microbes from skin to the flesh. Irradiation is a well-known technology for elimination of microbial contamination. Food irradiation has been approved by 50 countries and is being applied commercially in USA. The purpose of this study was to evaluate the effect of irradiation on the quality of minimally processed carrots. Fresh carrots were peeled, sliced and PE packaged. The samples were irradiated (0, 0.5, 1.0, 2.0, 2.5, 3.0 kGy) and stored at 5 deg. C for 2 weeks. The samples were analyzed for hardness, organoleptic acceptance and microbial load at 0, 7th and 15th day. The mean firmness of the control and all irradiated samples remained between 4.31 and 4.42 kg of force, showing no adverse effect of radiation dose. The effect of storage (2 weeks) was significant (P< 0.05) with values ranging between 4.28 and 4.39 kg of force. The total bacterial counts at 5 deg. C for non-irradiated and 0.5 kGy irradiated samples were 6.3x10{sup 5} cfu/g, 3.0x10{sup 2} and few colonies(>10) in all other irradiated samples(1.0, 2.0, 2.5 and 3.0 kGy) after 2 weeks storage. No coliform or E. coli were detected in any of the samples (radiated or control) immediately after irradiation and during the entire storage period in minimally processed carrots. A dose of 2.0 kGy completely controlled the fungal and bacterial counts. The irradiated samples (2.0 kGy) were also acceptable sensorially.

  5. Identification of irradiated spices by the use of thermoluminescence method (TL)

    Energy Technology Data Exchange (ETDEWEB)

    Sharifzadeh, M.; Sohrabpour, M. (Atomic Energy Organization of Iran, Teheran (Iran, Islamic Republic of))

    In this paper the results of the investigation of identification of irradiated spices by the use of thermoluminescence method is reported. The materials used were black and red peppers, turmeric, cinnamon, and garlic powder. Gamma Cell 220 was used for irradiating samples at dose values of 2.5, 5, 7.5 and 10 kGy respectively. The TL intensity of the unirradiated spices as well as the fading characteristics of the irradiated samples having received a dose of 10 kGy have been measured. Post-irradiation temperature treatment of the irradiated (10 kGy) and unirradiated samples at 60[sup o]C and 100[sup o]C for 24 hours have also been performed. The results show that the TL intensities of unirradiated and irradiated samples from different batches of each spice are fairly distributed. A reasonable TL intensity versus dose has been observed in nearly all cases. Based on the observation made it is possible to distinguish irradiated spices after (4-9) months post-irradiation. (author).

  6. Identification of irradiated spices by the use of thermoluminescence method (TL)

    International Nuclear Information System (INIS)

    Sharifzadeh, M.; Sohrabpour, M.

    1993-01-01

    In this paper the results of the investigation of identification of irradiated spices by the use of thermoluminescence method is reported. The materials used were black and red peppers, turmeric, cinnamon, and garlic powder. Gamma Cell 220 was used for irradiating samples at dose values of 2.5, 5, 7.5 and 10 kGy respectively. The TL intensity of the unirradiated spices as well as the fading characteristics of the irradiated samples having received a dose of 10 kGy have been measured. Post-irradiation temperature treatment of the irradiated (10 kGy) and unirradiated samples at 60 o C and 100 o C for 24 hours have also been performed. The results show that the TL intensities of unirradiated and irradiated samples from different batches of each spice are fairly distributed. A reasonable TL intensity versus dose has been observed in nearly all cases. Based on the observation made it is possible to distinguish irradiated spices after (4-9) months post-irradiation. (author)

  7. Impact of neutron irradiation on thermal helium desorption from iron

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Xunxiang, E-mail: hux1@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Field, Kevin G. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Taller, Stephen [University of Michigan, Ann Arbor, MI 48109 (United States); Katoh, Yutai [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Wirth, Brian D. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); University of Tennessee, Knoxville, TN 37996 (United States)

    2017-06-15

    The synergistic effect of neutron irradiation and transmutant helium production is an important concern for the application of iron-based alloys as structural materials in fission and fusion reactors. In this study, we investigated the impact of neutron irradiation on thermal helium desorption behavior in high purity iron. Single crystalline and polycrystalline iron samples were neutron irradiated in HFIR to 5 dpa at 300 °C and in BOR-60 to 16.6 dpa at 386 °C, respectively. Following neutron irradiation, 10 keV He ion implantation was performed at room temperature on both samples to a fluence of 7 × 10{sup 18} He/m{sup 2}. Thermal desorption spectrometry (TDS) was conducted to assess the helium diffusion and clustering kinetics by analyzing the desorption spectra. The comparison of He desorption spectra between unirradiated and neutron irradiated samples showed that the major He desorption peaks shift to higher temperatures for the neutron-irradiated iron samples, implying that strong trapping sites for He were produced during neutron irradiation, which appeared to be nm-sized cavities through TEM examination. The underlying mechanisms controlling the helium trapping and desorption behavior were deduced by assessing changes in the microstructure, as characterized by TEM, of the neutron irradiated samples before and after TDS measurements.

  8. Keeping carrots quality during storage by irradiation

    International Nuclear Information System (INIS)

    El-Nashaby, F.M.; Hafez, S.A.

    2000-01-01

    Fresh carrots were gamma irradiated at 0, 0.1, 0.2, 0.5 and 1.0 KGy doses using cobalt-60 source. A portion of the irradiated carrots was stored at ambient temperature (20-25 degree C) and the rest was packed in polyethylene bags and stored in refrigerator temperature (5± 1 degree C). The results indicated that the sprouting of carrots were completely inhibited by radiation dose of 0.2 KGy either at ambient temperature or cold storage, while the non-irradiated samples started to sprout after 2 and 4 weeks of storage at ambient temperature and cold storage respectively. Furthermore, samples treated with gamma rays showed lower values of weight loss compared to the untreated ones during storage. Concerning storage temperature, it was found that the rate of weight loss during storage was higher at ambient temperature than in refrigerator. Micro-organisms were greatly affected by gamma rays, their counts were found to be decreased by increasing irradiation dose as compared with the control sample. Moreover, during storage period, refrigerated samples showed lower bacterial and molds counts than samples stored at ambient temperature. On the other hand, it was also observed that irradiated samples at the higher dose i.e. 1.0 KGy stored either at ambient temperature or in refrigerator showed higher bacterial and molds counts than unirradiated ones. The lowest dose (0.1 KGy) had no effect on carotene and sugars contents of carrots while increasing the dose above 0.2 KGy led to gradual decrease in carotene contents and gradual increase in total soluble sugars contents of the samples with increasing the irradiation dose compared with the nonirradiated ones. The results proved that gamma irradiation dose of 0.2 Gy was effective for sprout inhibition of carrots and increase their shelf-life to 10 weeks at ambient temperature without adverse effects on carotene and sugars contents of treated carrots

  9. EPR study on gamma-irradiated fruits dehydrated via osmosis

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Aleksieva, K.

    2007-01-01

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and γ-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas γ-irradiated exhibit 'sugar-like' EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples

  10. EPR study on gamma-irradiated fruits dehydrated via osmosis

    Science.gov (United States)

    Yordanov, N. D.; Aleksieva, K.

    2007-06-01

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and γ-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas γ-irradiated exhibit "sugar-like" EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples.

  11. Sprouting inhibition of rhizomes by gamma irradiation

    International Nuclear Information System (INIS)

    Hilmy, Nazly; Chosdu, Rahayu

    1985-01-01

    Sprouting inhibition by gamma irradiation to prolong the storage life of 4 species of rhizomes, namely curcuma domestica, kaemferia galanga, curcuma xanthoriza and curcuma aeruginosa, has been carried out. Two groups of samples were used, freshly harvested rhizomes and fresh rhizomes which have been stored for about two weeks. The samples were packed in a plastic net bag, each contained about 100 grams of rhizomes. Irradiation was carried out at room temperature at the doses of 0, 0.02, 0.04, 0.06, 0.08, 0.10, 0.15, 0.20 and 0.25 kGy. Post irradiation storage was done at room temperature with relative humidity ranging between 85 and 95%. The results showed that irradiation doses of 0.06 to 0.08 kGy was sufficient to inhibit sprouting of freshly harvested rhizomes and prolonged its storage life for 6 weeks, while in the other group sprouting still occured at the dose of 0.25 kGy. Irradiation dose up to 0.25 kGy did not cause significant effect on moisture and volatile oil contents, as well as volatile oil characteristics of the samples. About 50% of weight losses were found either in irradiated or unirradiated samples after being stored for 8 weeks. Odour and texture were evaluated organoleptically while mould growth and insect damage were observed visually. (author)

  12. Microbial determination of Cumin by gamma irradiation

    International Nuclear Information System (INIS)

    Motamedi, F.; Abhari, M.; Fathollahi, H.; Arbabi, K.

    2002-01-01

    Cumin is one of the valuable export items of Iran, and like most of the agricultural products it is contaminated by microorganisms. Due to importance of this product, the gamma irradiation method, which has applications in microbial decontamination, has been used for the improving its quality and increasing the shelf life-time. For this purpose pak ages of 10 gr of cumin were irradiated by 2,4,6 and 8 KGy from 60 Co source. With each dose, four samples were irradiated and results were compared with controlled not irradiated samples. According to the standard limitation of bacteria and molds the total optimum doses are 7.5 and 5 KGy respectively

  13. Detection of irradiated spices using photo-stimulated luminescence technique (PSL)

    Energy Technology Data Exchange (ETDEWEB)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi [Faculty of Science and Technology, National University of Malaysia, Bangi, 43000 Kajang, Selangor (Malaysia); Othman, Zainon; Abdullah, Wan Saffiey Wan [Malaysian Nuclear Agency, Bangi 43000 Kajang, Selangor (Malaysia)

    2014-09-03

    Photo-stimulated luminescence (PSL) technique was applied to detect irradiated black pepper (Piper nigrum), cinnamon (Cinnamomum verum) and turmeric (Curcuma longa) after dark storage for 1 day, 3 and 6 months. Using screening and calibrated PSL, all samples were correctly discriminated between non-irradiated and spices irradiated with doses 1, 5 and 10 kGy. The PSL photon counts (PCs) of irradiated spices increased with increasing dose, with turmeric showing highest sensitivity index to irradiation compared to black pepper and cinnamon. The differences in response are possibly attributed to the varying quantity and quality of silicate minerals present in each spice sample. PSL signals of all irradiated samples reduced after 3 and 6 months storage. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated spices.

  14. Detection of irradiated spices using photo-stimulated luminescence technique (PSL)

    International Nuclear Information System (INIS)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon; Abdullah, Wan Saffiey Wan

    2014-01-01

    Photo-stimulated luminescence (PSL) technique was applied to detect irradiated black pepper (Piper nigrum), cinnamon (Cinnamomum verum) and turmeric (Curcuma longa) after dark storage for 1 day, 3 and 6 months. Using screening and calibrated PSL, all samples were correctly discriminated between non-irradiated and spices irradiated with doses 1, 5 and 10 kGy. The PSL photon counts (PCs) of irradiated spices increased with increasing dose, with turmeric showing highest sensitivity index to irradiation compared to black pepper and cinnamon. The differences in response are possibly attributed to the varying quantity and quality of silicate minerals present in each spice sample. PSL signals of all irradiated samples reduced after 3 and 6 months storage. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated spices

  15. Detection of irradiated spices using photo-stimulated luminescence technique (PSL)

    Science.gov (United States)

    Ramli, Ros Anita Ahmad; Yasir, Muhamad Samudi; Othman, Zainon; Abdullah, Wan Saffiey Wan

    2014-09-01

    Photo-stimulated luminescence (PSL) technique was applied to detect irradiated black pepper (Piper nigrum), cinnamon (Cinnamomum verum) and turmeric (Curcuma longa) after dark storage for 1 day, 3 and 6 months. Using screening and calibrated PSL, all samples were correctly discriminated between non-irradiated and spices irradiated with doses 1, 5 and 10 kGy. The PSL photon counts (PCs) of irradiated spices increased with increasing dose, with turmeric showing highest sensitivity index to irradiation compared to black pepper and cinnamon. The differences in response are possibly attributed to the varying quantity and quality of silicate minerals present in each spice sample. PSL signals of all irradiated samples reduced after 3 and 6 months storage. The results of this study provide a useful database on the applicability of PSL technique for the detection of Malaysian irradiated spices.

  16. Determination of uranium concentration and burn-up of irradiated reactor fuel in contaminated areas in Belarus using uranium isotopic ratios in soil samples

    International Nuclear Information System (INIS)

    Mironov, V.P.; Matusevich, J.L.; Kudrjashov, V.P.; Ananich, P.I.; Zhuravkov, V.V.; Boulyga, S.F.; Becker, J.S.

    2005-01-01

    An analytical method is described for the estimation of uranium concentrations, of 235 U/ 238 U and 236 U/ 238 U isotope ratios and burn-up of irradiated reactor uranium in contaminated soil samples by inductively coupled plasma mass spectrometry. Experimental results obtained at 12 sampling sites situated on northern and western radioactive fallout tails 4 to 53 km distant from Chernobyl nuclear power plant (NPP) are presented. Concentrations of irradiated uranium in the upper 0-10 cm soil layers at the investigated sampling sites varied from 2.1 x 10 -9 g/g to 2.0 x 10 -6 g/g depending mainly on the distance from Chernobyl NPP. A slight variation of the degree of burn-up of spent reactor uranium was revealed by analyzing 235 U/ 238 U and 236 U/ 238 U isotope ratios and the average value amounted to 9.4±0.3 MWd/(kg U). (orig.)

  17. Determination of uranium concentration and burn-up of irradiated reactor fuel in contaminated areas in Belarus using uranium isotopic ratios in soil samples

    Energy Technology Data Exchange (ETDEWEB)

    Mironov, V.P.; Matusevich, J.L.; Kudrjashov, V.P.; Ananich, P.I.; Zhuravkov, V.V. [Inst. of Radiobiology, Minsk Univ. (Belarus); Boulyga, S.F. [Inst. of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg-Univ. Mainz, Mainz (Germany); Becker, J.S. [Central Div. of Analytical Chemistry, Research Centre Juelich, Juelich (Germany)

    2005-07-01

    An analytical method is described for the estimation of uranium concentrations, of {sup 235}U/{sup 238}U and {sup 236}U/{sup 238}U isotope ratios and burn-up of irradiated reactor uranium in contaminated soil samples by inductively coupled plasma mass spectrometry. Experimental results obtained at 12 sampling sites situated on northern and western radioactive fallout tails 4 to 53 km distant from Chernobyl nuclear power plant (NPP) are presented. Concentrations of irradiated uranium in the upper 0-10 cm soil layers at the investigated sampling sites varied from 2.1 x 10{sup -9}g/g to 2.0 x 10{sup -6}g/g depending mainly on the distance from Chernobyl NPP. A slight variation of the degree of burn-up of spent reactor uranium was revealed by analyzing {sup 235}U/{sup 238}U and {sup 236}U/{sup 238}U isotope ratios and the average value amounted to 9.4{+-}0.3 MWd/(kg U). (orig.)

  18. Ionic conductivity in irradiated KCL

    International Nuclear Information System (INIS)

    Vignolo Rubio, J.

    1979-01-01

    The ionic conductivity of X and gamma irradiated KCl single crystals has been studied between room temperature and 600 deg C. The radiation induced damage resulting in a decrease of the conductivity heals by thermal annealing in two steps which are at about 350 and 550 deg C respectively. It has been found that the radiation induced colour centres are not involved in the observed decrease of the ionic conductivity. Howewer, it has been observed that the effects of quenching and plastic deformation on the conductivity of the samples are very similar to the effect induced by irradiation. It is suggested that small radiation induced dislocation loops might cause the ionic conductivity decrease observed in irradiated samples. (auth)

  19. Study of irradiation effect on curcuma polyphenols

    International Nuclear Information System (INIS)

    Rejeb, Imen

    2008-01-01

    The present study was carried out to evaluate the effect of gamma irradiation on curcumin (Curcuma Longa rhizome) component, particularly the polyphenolic fraction. Powdered rhizome was irradiated at 0, 5, 10 and 15 KGy (dose rate of 6 KGy / H). Polyphenolics were extracted and total polyphenols conent (TPC) was quantified using the Folin-Ciocalteau method. The irradiation effect was also evaluated by the HPLC technique. The chromatographic analysis showed that the irradiated and non-irradiated curcumin spectrum gave similar data. The antioxidant and antibacterial activities of the phenolic extracts were also assessed. the anti oxidative potential of the sample was evaluated using two radical scavenging methods with DPPH and ABTS. The antimicrobial analysis showed that the phenolic extracts of curcumin inhibited the growth of the studied microorganisms. Our results showed that irradiated samples were not affected in terms of polyphenols content and characteristics. (Author)

  20. Identification of irradiated pepper by ESR measurement

    International Nuclear Information System (INIS)

    Morishita, Norio; Kume, Tamikazu; Kawakami, Waichiro; Ishigaki, Isao

    1988-01-01

    The possibility of using electron spin resonance (ESR) for identification of irradiated black and white pepper was examined. The ESR spectra induced by irradiation with 10 kGy are clearly distinguishable from that of unirradiated samples. The intensity of signal induced by irradiation was markedly reduced during 2 weeks storage but it was slowly reduced on further storage. The difference of intensity between the irradiated and unirradiated samples can be distinguished after 13 weeks storage. In this experiment, ground black pepper, ground white pepper and whole white pepper can be identified after 13 weeks. On the other hand, whole black pepper cannot be identified after 8 weeks because of the variation of values. It suggests that the suitable method for sample preparation such as separation of pellicle of whole black pepper is required before ESR measurement. (author)

  1. Corrosion characteristics of Hastelloy N alloy after He+ ion irradiation

    International Nuclear Information System (INIS)

    Lin Jianbo; Yu Xiaohan; Li Aiguo; He Shangming; Cao Xingzhong; Wang Baoyi; Li Zhuoxin

    2014-01-01

    With the goal of understanding the invalidation problem of irradiated Hastelloy N alloy under the condition of intense irradiation and severe corrosion, the corrosion behavior of the alloy after He + ion irradiation was investigated in molten fluoride salt at 700 °C for 500 h. The virgin samples were irradiated by 4.5 MeV He + ions at room temperature. First, the virgin and irradiated samples were studied using positron annihilation lifetime spectroscopy (PALS) to analyze the influence of irradiation dose on the vacancies. The PALS results showed that He + ion irradiation changed the size and concentration of the vacancies which seriously affected the corrosion resistance of the alloy. Second, the corroded samples were analyzed using synchrotron radiation micro-focused X-ray fluorescence, which indicated that the corrosion was mainly due to the dealloying of alloying element Cr in the matrix. Results from weight-loss measurement showed that the corrosion generally correlated with the irradiation dose of the alloy. (author)

  2. Neutron self-shielding with k0-NAA irradiations

    International Nuclear Information System (INIS)

    Chilian, C.; Chambon, R.; Kennedy, G.

    2010-01-01

    A sample of SMELS Type II reference material was mixed with powdered Cd-nitrate neutron absorber and analysed by k 0 NAA for 10 elements. The thermal neutron self-shielding effect was found to be 34.8%. When flux monitors were irradiated sufficiently far from the absorbing sample, it was found that the self-shielding could be corrected accurately using an analytical formula and an iterative calculation. When the flux monitors were irradiated 2 mm from the absorbing sample, the calculations over-corrected the concentrations by as much as 30%. It is recommended to irradiate flux monitors at least 14 mm from a 10 mm diameter absorbing sample.

  3. Identification of gamma-irradiated fruit juices by EPR spectroscopy

    International Nuclear Information System (INIS)

    Aleksieva, K.I.; Dimov, K.G.; Yordanov, N.D.

    2014-01-01

    The results of electron paramagnetic resonance (EPR) study on commercially available juices from various fruits and different fruit contents: 25%, 40%, 50%, and 100%, homemade juices, nectars and concentrated fruit syrups, before and after gamma-irradiation are reported. In order to remove water from non- and irradiated samples all juices and nectars were filtered; the solid residue was washed with alcohol and dried at room temperature. Only concentrated fruit syrups were dried for 60 min at 40 °C in a standard laboratory oven. All samples under study show a singlet EPR line with g=2.0025 before irradiation with exception of concentrated fruit syrups, which are EPR silent. Irradiation of juice samples gives rise to complex EPR spectra which gradually transferred to “cellulose-like” EPR spectrum from 25% to 100% fruit content. Concentrated fruit syrups show typical “sugar-like“ spectra due to added saccharides. All EPR spectra are characteristic and can prove radiation treatment. The fading kinetics of radiation-induced EPR signals were studied for a period of 60 days after irradiation. - Highlights: • The EPR analysis of juices, nectars and syrups proves that the sample has been irradiated. • Two sample preparation procedures were used. • The stability of the radiation induced EPR signals was studied over 2 months. • Application of European standards can be extended for irradiated juices and syrups

  4. Identification of gamma-irradiated foodstuffs by chemiluminescence measurements in Taiwan

    Science.gov (United States)

    Ma, Ming-Shia Chang; Chen, Li-Hsiang; Tsai, Zei-Tsan; Fu, Ying-Kai

    In order to establish chemiluminescence (CL) measurements as an identification method for γ-irradiated foodstuffs in Taiwan, ten agricultural products including wheat flour, rice, ginger, potatoes, garlic, onions, red beans, mung beans, soy beans, xanthoxylon seeds and Japanese star anises have been tested to compare CL intensities between untreated samples and samples subject to a 10 kGy γ-irradiation dose. Amongst them, wheat flour is the most eligible product to be identified by CL measurements. The CL intensities of un-irradiated and irradiated flour have shown large differences associated with a significant dose-effect relationship. Effects of three different protein contents of flour, unsieved and sieved (100-200 mesh), the reproducibility and the storage experiment on CL intensities at various doses were investigated in this study. In addition, the white bulb part of onions has shown some CL in irradiated samples. The CL data obtained from the other eight agricultural products have shown large fluctuations and cannot be used to differentiate between irradiated and un-irradiated samples.

  5. Identification of gamma-irradiated foodstuffs by chemiluminescence measurements in Taiwan

    International Nuclear Information System (INIS)

    Mingshia Chang Ma; Lihsiang Chen; Zeitsan Tsai; Yingkai Fu

    1992-01-01

    In order to establish chemiluminescence (CL) measurements as an identification method for γ-irradiated foodstuffs in Taiwan, ten agricultural products including wheat flour, rice, ginger, potatoes, garlic, onions, red beans, mung beans, soy beans, xanthoxylon seeds and Japanese star anises have been tested to compare CL intensities between untreated samples and samples subject to a 10 kGy γ-irradiation dose. Amongst them, wheat flour is the most eligible product to be identified by CL measurements. The CL intensities of un-irradiated and irradiated flour have shown large differences associated with a significant dose-effect relationship. Effects of three different protein contents of flour, unsieved and sieved (100-200 mesh), the reproducibility and the storage experiment on CL intensities at various doses were investigated in this study. In addition, the white bulb part of onions has shown some CL in irradiated samples. The CL data obtained from the other eight agricultural products have shown large fluctuations and cannot be used to differentiate between irradiated and un-irradiated samples. (Author)

  6. Ion irradiated graphite exposed to fusion-relevant deuterium plasma

    International Nuclear Information System (INIS)

    Deslandes, Alec; Guenette, Mathew C.; Corr, Cormac S.; Karatchevtseva, Inna; Thomsen, Lars; Ionescu, Mihail; Lumpkin, Gregory R.; Riley, Daniel P.

    2014-01-01

    Graphite samples were irradiated with 5 MeV carbon ions to simulate the damage caused by collision cascades from neutron irradiation in a fusion environment. The ion irradiated graphite samples were then exposed to a deuterium plasma in the linear plasma device, MAGPIE, for a total ion fluence of ∼1 × 10 24 ions m −2 . Raman and near edge X-ray absorption fine structure (NEXAFS) spectroscopy were used to characterize modifications to the graphitic structure. Ion irradiation was observed to decrease the graphitic content and induce disorder in the graphite. Subsequent plasma exposure decreased the graphitic content further. Structural and surface chemistry changes were observed to be greatest for the sample irradiated with the greatest fluence of MeV ions. D retention was measured using elastic recoil detection analysis and showed that ion irradiation increased the amount of retained deuterium in graphite by a factor of four

  7. Effect of Gamma Irradiation on Water Uptake Rate and Gelatinization of Brown Rice

    International Nuclear Information System (INIS)

    Shu, C.S.; Lee, J.W.; Lee, Y.S.; Byun, M.W.

    2004-01-01

    Effects of gamma irradiation on brown rice quality were evaluated. Brown rice was irradiated at absorbed dose of 1, 3 or 5 kGy, and ground. Water uptake, pasting properties, and physicochemical characteristics of flour samples were tested. Water uptake rates of irradiated samples were higher than that of control, and were dose-dependent. Hydration capacity decreased in sample irradiated at 5 kGy due to leaching out of soluble compounds, whereas no differences were observed among other irradiated samples and control

  8. Calibrated photostimulated luminescence is an effective approach to identify irradiated orange during storage

    Science.gov (United States)

    Jo, Yunhee; Sanyal, Bhaskar; Chung, Namhyeok; Lee, Hyun-Gyu; Park, Yunji; Park, Hae-Jun; Kwon, Joong-Ho

    2015-06-01

    Photostimulated luminescence (PSL) has been employed as a fast screening method for various irradiated foods. In this study the potential use of PSL was evaluated to identify oranges irradiated with gamma ray, electron beam and X-ray (0-2 kGy) and stored under different conditions for 6 weeks. The effects of light conditions (natural light, artificial light, and dark) and storage temperatures (4 and 20 °C) on PSL photon counts (PCs) during post-irradiation periods were studied. Non-irradiated samples always showed negative values of PCs, while irradiated oranges exhibited intermediate results after first PSL measurements. However, the irradiated samples had much higher PCs. The PCs of all the samples declined as the storage time increased. Calibrated second PSL measurements showed PSL ratio <10 for the irradiated samples after 3 weeks of irradiation confirming their irradiation status in all the storage conditions. Calibrated PSL and sample storage in dark at 4 °C were found out to be most suitable approaches to identify irradiated oranges during storage.

  9. Detection of irradiation treatment of foods using DNA 'comet assay'

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Hasan M.; Delincee, Henry

    1998-06-01

    Microgel electrophoresis of single cells (DNA comet assay) has been investigated to detect irradiation treatment of some food samples. These samples of fresh and frozen rainbow trout, red lentil, gram and sliced almonds were irradiated to 1 or 2 kGy using 10 MeV electron beam from a linear accelerator. Rainbow trout samples yielded good results with samples irradiated to 1 or 2 kGy showing fragmentation of DNA and, therefore, longer comets with no intact cells. Unirradiated samples showed shorter comets with a significant number of intact cells. For rainbow trout stored in a freezer for 11 days the irradiated samples can still be discerned by electrophoresis from unirradiated samples, however, the unirradiated trouts also showed some longer comets besides some intact cells. Radiation treatment of red lentils can also be detected by this method, i.e. no intact cells in 1 or 2 kGy irradiated samples and shorter comets and some intact cells in unirradiated samples. However, the results for gram and sliced almond samples were not satisfactory since some intact DNA cells were observed in irradiated samples as well. Probably, incomplete lysis has led to these deviating results.

  10. ESR analysis of irradiated red peppers and commercial red peppers in Japan

    International Nuclear Information System (INIS)

    Kameya, Hiromi; Ukai, Mitsuko

    2011-01-01

    ESR analysis of γ-ray irradiated and being treated with different processing red pepper was studied. All the red peppers were commercial expect irradiated one. Processing treatment of red pepper was sun drying, mechanical processing (heating sterilization and powdering treatment). All the samples were weighted and analyzed. The ESR spectrum of the red pepper is composed of a singlet at g=2.00. This signal was originated from organic free radical. It is suggested the effect of heating treatment on the radical formation is not so large and powdering treatment will promote the radical formation of red pepper. ESR singlet signal of the irradiated red pepper showed the large signal intensity and the dose-dependence. The singlet signal intensity of irradiated powder sample showed the almost same value as compared with that of the powder sample with heating treatment. Relaxation times (T 1 and T 2 ) of the singlet signal were calculated. The relaxation behavior and relaxation times of the irradiated sample were different from that of the non-irradiated sample. The value of T 1 , the spin lattice relaxation time, of irradiated sample was increased and T 2 , the spin-spin relaxation time, of irradiated sample was decreased. We concluded that the radical formation of the red pepper is mainly depended on the powdering treatment and irradiation. (author)

  11. Study of the effects of low-fluence laser irradiation on wall paintings: Test measurements on fresco model samples

    Science.gov (United States)

    Raimondi, Valentina; Cucci, Costanza; Cuzman, Oana; Fornacelli, Cristina; Galeotti, Monica; Gomoiu, Ioana; Lognoli, David; Mohanu, Dan; Palombi, Lorenzo; Picollo, Marcello; Tiano, Piero

    2013-11-01

    Laser-induced fluorescence is widely applied in several fields as a diagnostic tool to characterise organic and inorganic materials and could be also exploited for non-invasive remote investigation of wall paintings using the fluorescence lidar technique. The latter relies on the use of a low-fluence pulsed UV laser and a telescope to carry out remote spectroscopy on a given target. A first step to investigate the applicability of this technique is to assess the effects of low-fluence laser radiation on wall paintings. This paper presents a study devoted to investigate the effects of pulsed UV laser radiation on a set of fresco model samples prepared using different pigments. To irradiate the samples we used a tripled-frequency Q-switched Nd:YAG laser (emission wavelength: 355 nm; pulse width: 5 ns). We varied the laser fluence from 0.1 mJ/cm2 to 1 mJ/cm2 and the number of laser pulses from 1 to 500 shots. We characterised the investigated materials using several diagnostic and analytical techniques (colorimetry, optical microscopy, fibre optical reflectance spectroscopy and ATR-FT-IR microscopy) to compare the surface texture and their composition before and after laser irradiation. Results open good prospects for a non-invasive investigation of wall paintings using the fluorescence lidar technique.

  12. Study of the effects of low-fluence laser irradiation on wall paintings: Test measurements on fresco model samples

    International Nuclear Information System (INIS)

    Raimondi, Valentina; Cucci, Costanza; Cuzman, Oana; Fornacelli, Cristina; Galeotti, Monica; Gomoiu, Ioana; Lognoli, David; Mohanu, Dan; Palombi, Lorenzo; Picollo, Marcello; Tiano, Piero

    2013-01-01

    Laser-induced fluorescence is widely applied in several fields as a diagnostic tool to characterise organic and inorganic materials and could be also exploited for non-invasive remote investigation of wall paintings using the fluorescence lidar technique. The latter relies on the use of a low-fluence pulsed UV laser and a telescope to carry out remote spectroscopy on a given target. A first step to investigate the applicability of this technique is to assess the effects of low-fluence laser radiation on wall paintings. This paper presents a study devoted to investigate the effects of pulsed UV laser radiation on a set of fresco model samples prepared using different pigments. To irradiate the samples we used a tripled-frequency Q-switched Nd:YAG laser (emission wavelength: 355 nm; pulse width: 5 ns). We varied the laser fluence from 0.1 mJ/cm 2 to 1 mJ/cm 2 and the number of laser pulses from 1 to 500 shots. We characterised the investigated materials using several diagnostic and analytical techniques (colorimetry, optical microscopy, fibre optical reflectance spectroscopy and ATR-FT-IR microscopy) to compare the surface texture and their composition before and after laser irradiation. Results open good prospects for a non-invasive investigation of wall paintings using the fluorescence lidar technique.

  13. EPR study on gamma-irradiated fruits dehydrated via osmosis

    Energy Technology Data Exchange (ETDEWEB)

    Yordanov, N.D. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)]. E-mail: ndyepr@bas.bg; Aleksieva, K. [Laboratory EPR, Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2007-06-15

    The shape and time stability of the electron paramagnetic resonance (EPR) spectra of non- and {gamma}-irradiated papaya, melon, cherry and fig samples dehydrated via osmosis are reported. It is shown that non-irradiated samples are generally EPR silent whereas {gamma}-irradiated exhibit 'sugar-like' EPR spectra. The recorded EPR spectra are monitored for a period of 7 months after irradiation (stored at low humidity and in the dark). The results suggest longer period of unambiguous identification of the radiation processing of osmose dehydrated fruits. Therefore, the Protocol EN 13708,2001 issued by CEN is fully applicable for the studied fruit samples.

  14. Effects of gamma irradiation on deteriorated paper

    Science.gov (United States)

    Bicchieri, Marina; Monti, Michela; Piantanida, Giovanna; Sodo, Armida

    2016-08-01

    Even though gamma radiation application, also at the minimum dosage required for disinfection, causes depolymerization and degradation of the paper substrate, recently published papers seemed, instead, to suggest that γ-rays application could be envisaged in some conditions for Cultural Heritage original documents and books. In some of the published papers, the possible application of γ-rays was evaluated mainly by using mechanical tests that scarcely reflect the chemical modifications induced in the cellulosic support. In the present article the effect of low dosage γ-irradiation on cellulosic substrates was studied and monitored applying different techniques: colorimetry, spectroscopic measurements, carbonyl content and average viscometric degree of polymerization. Two different papers were investigated, a non-sized, non-filled cotton paper, and a commercial permanent paper. To simulate a real deteriorated document, which could need γ-rays irradiation, some samples were submitted to a hydrolysis treatment. We developed a treatment based on the exposition of paper to hydrochloric acid vapors, avoiding any contact of the samples with water. This method induces a degradation similar to that observed on original documents. The samples were then irradiated with 3 kGy γ-rays at a 5258 Gy/h rate. The aforementioned analyses were performed on the samples just irradiated and after artificial ageing. All tests showed negative effects of gamma irradiation on paper. Non-irradiated paper preserves better its appearance and chemical properties both in the short term and after ageing, while the irradiated samples show appreciable color change and higher oxidation extent. Since the Istituto centrale restauro e conservazione patrimonio archivistico e librario is responsible for the choice of all restoration treatments that could be applied on library and archival materials under the protection of the Italian State (http://www.icpal.beniculturali.it/allegati/DM-7

  15. Irradiation effect on onion keeping-quality after sea-shipment from Argentina to the Netherlands

    International Nuclear Information System (INIS)

    Wolters, T.C.; Langerak, D.I.; Curzio, O.A.; Croci, C.A.

    1990-01-01

    Onion losses occur due to sprouting and rot. Onion cultivar Valenciana was irradiated with 60 Gy, shipped from Argentina to the Netherlands, and stored 6 months at 4 degrees C. The rot in unirradiated samples increased after 4 months while rot in irradiated samples remained almost constant. Irradiation almost completely prevented sprouting. Storage losses were 50% for unirradiated and 20% for irradiated samples. Irradiated samples showed an improvement in general appearance. Irradiation reduced weight loss and damaged bulbs were more susceptible to storage rot

  16. Irradiation processing of potatoes, onions and garlic

    International Nuclear Information System (INIS)

    Jan, M.; Starr, A.; Wahid, M.; Ahmad, A.; Khan, I.

    1992-07-01

    In this report, studies have been conducted on irradiation preservation of potatoes, onions and garlic involving different varieties, harvesting season and storage life. As a result of these investigations, optimum conditions were established for each crop. The effect of irradiation and storage on sprouting, rottage and weight loss of potatoes is presented. The sprouting initiated in the unirradiated samples after 2 months reaching 51, 80 and 100% on 4, 5 and 6 months storage respectively. Weight losses were observed in the irradiated and unirradiated samples. (A.B.)

  17. Thermoluminescence response of gamma-irradiated sesame with mineral dust

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez L, Y. [CSIC, Instituto de Estructura de la Materia, Calle Serrano 121, 28006 Madrid (Spain); Correcher, V. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Garcia G, J. [CSIC, Museo Nacional de Ciencias Naturales, Calle Jose Gutierrez Abascal 2, 28006 Madrid (Spain); Cruz Z, E., E-mail: y.r.l@csic.es [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior s/n, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2011-10-15

    The thermoluminescence (Tl) emission of minerals isolated from Mexican and Indian sesame seeds appear as a good tool to discern between irradiated and non-irradiated samples. According to the X-ray diffraction and environmental scanning microscope, the adhered dust in both samples is mainly composed by different amounts of quartz and feldspars. These mineral phases exhibit (i) enough sensitivity to ionizing radiation inducing good Tl intensity, (ii) high stability of the Tl signal during the storage of the material (i.e. low fading) and (iii) are thermally and chemically stable. Blind tests performed under laboratory conditions, but simulating industrial preservation processes (similar temperature and moisture, and presence of white light), allows to distinguish between 1 KGy gamma-irradiated and non-irradiated samples even 11000 hours (15 months) after the irradiation proceeding. (Author)

  18. Thermoluminescence response of gamma-irradiated sesame with mineral dust

    International Nuclear Information System (INIS)

    Rodriguez L, Y.; Correcher, V.; Garcia G, J.; Cruz Z, E.

    2011-10-01

    The thermoluminescence (Tl) emission of minerals isolated from Mexican and Indian sesame seeds appear as a good tool to discern between irradiated and non-irradiated samples. According to the X-ray diffraction and environmental scanning microscope, the adhered dust in both samples is mainly composed by different amounts of quartz and feldspars. These mineral phases exhibit (i) enough sensitivity to ionizing radiation inducing good Tl intensity, (ii) high stability of the Tl signal during the storage of the material (i.e. low fading) and (iii) are thermally and chemically stable. Blind tests performed under laboratory conditions, but simulating industrial preservation processes (similar temperature and moisture, and presence of white light), allows to distinguish between 1 KGy gamma-irradiated and non-irradiated samples even 11000 hours (15 months) after the irradiation proceeding. (Author)

  19. The effect of deformation twinning on irradiation embrittlement in iron single crystals

    International Nuclear Information System (INIS)

    Kayano, Hideo; Tokutomi, Shoichiro; Yajima, Seishi; Takaku, Hiroshi.

    1978-01-01

    Single crystals of iron with the [100] crystal orientation were irradiated in JMTR with fast neutrons to a fluence of 8 x 10 18 n/cm 2 (E > 1 MeV). All samples were deformed in tension at temperatures from liquid nitrogen temperature to 200 0 C at different strain rates using an Instron-type tensile testing machine. Scanning electron microscopy of the fractured surfaces revealed that deformation twinning is difficult to occur in irradiated samples, and also that twins formed in both irradiated and unirradiated samples inhibit fracture nucleation and growth. From the results of tensile deformation of the irradiated samples deformed in tension a different strain rates at 159 0 K, it is conceived that twinning suppression is greater in the irradiated than in the unirradiated samples, and that the nucleation and growth of twins are not necessarily related to those of cracks. It is suggested that the irradiation-induced defects impede plastic deformation of the crystals and deformation twinning is suppressed by irradiation, thus causing the irradiation embrittlement. (auth.)

  20. Identifying irradiated flour by photo-stimulated luminescence technique

    International Nuclear Information System (INIS)

    Ros Anita Ahmad Ramli; Muhammad Samudi Yasir; Zainon Othman; Wan Saffiey Wan Abdullah

    2013-01-01

    Full-text: The photo-stimulated luminescence technique is recommended by European Committee for standardization for the detection food irradiation (EN 13751:2009). This study shows on luminescence technique to identify gamma irradiated five types of flour (corn flour, tapioca flour, wheat flour, glutinos rice flour and rice flour) at three difference dose levels in the range 0.2 - 1 kGy. The signal level is compare with two thresholds (700 and 5000). The majority of irradiated samples produce a strong signal above the upper threshold (5000 counts/ 60 s). All the control samples gave negative screening result while the signals below the lower threshold (700 counts/ 60s) suggest that the sample has not been irradiated. A few samples show the signal levels between the two thresholds (intermediate signals) suggest that further investigation. Reported procedure was also tested over 60 days, confirming the applicability and feasibility of proposed methods. (author)

  1. Investigation of microstructure and mechanical properties of proton irradiated Zircaloy 2

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Apu, E-mail: asarkar@barc.gov.in [Mechanical Metallurgy Division, Bhabha Atomic Reserch Centre, Mumbai, 400 085 (India); Kumar, Ajay [Nuclear Physics Division, Bhabha Atomic Reserch Centre, Mumbai, 400 085 (India); Mukherjee, S.; Sharma, S.K.; Dutta, D.; Pujari, P.K. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai, 400 085 (India); Agarwal, A.; Gupta, S.K.; Singh, P. [Ion Accelerator Development Division, Bhabha Atomic Research Centre, Mumbai, 400 085 (India); Chakravartty, J.K. [Mechanical Metallurgy Division, Bhabha Atomic Reserch Centre, Mumbai, 400 085 (India)

    2016-10-15

    Samples of Zircaloy 2 have been irradiated with 4 MeV protons to two different doses. Microstructures of the unirradiated and irradiated samples have been characterized by Electron Back Scatter Diffraction (EBSD), X-ray diffraction line profile analysis (XRDLPA), Positron Annihilation Lifetime Spectroscopy (PALS) and Coincident Doppler Broadening (CDB) Spectroscopy. Tensile tests and micro hardness measurements have been carried out at room temperature to assess the changes in mechanical properties of Zircaloy 2 due to proton irradiation. The correlation of dislocation density, grain size and yield stress of the irradiated samples indicated that an increase in dislocation density due to irradiation is responsible for the change in mechanical behavior of irradiated Zircaloy.

  2. Application of thermoluminescence analysis for detection of irradiated foodstuffs

    International Nuclear Information System (INIS)

    Malec-Czechowska, K.; Dancewicz, M.; Szot, Z.

    1996-01-01

    Investigations on the development conditions necessary to obtain reliable results of the detection of irradiated herbs, spices, mushrooms and strawberries by thermoluminescence (Tl) method in whole samples and/or in minerals isolated from them carried out. Tl intensities of whole samples were measured between 40 an 355 C. Threshold values for non-irradiated samples were obtained by multiplying Tl values of control samples by 3 (safety factor). Samples in which Tl intensities were higher than the threshold values were identified as irradiated. In 4 out of 10 kind of herbs and spices examined the results of Tl measurements led to false identification. (author). 14 refs, 1 fig., 5 tabs

  3. Improvement of microbiological qualities of namphrik by gamma irradiation

    International Nuclear Information System (INIS)

    Chahorm, K; Neramitmansook, N; Kongsang, N; Ko, J

    2017-01-01

    Twenty samples of Namphrik from commercial markets were evaluated the microbiological qualities. It was found that 15 samples did not meet Thai Community Product Standard. The total plate count (TPC) in 15 samples were higher than the maximum limits (1.60x10 4 – 4.4x10 5 CFU/g). In addition, the other pathogens were higher than the maximum limits such as B. cereus in 11 samples (2.10x10 3 – 6.10x10 4 CFU/g) S. aureus in 2 samples (15 – 40 CFU/g) Clostridium perfringens in 4 samples (1.00x10 2 – 8.8x10 3 CFU/g) and yeast and mold in 9 samples (3.00 x10 2 – 9.00x10 3 CFU/g). To reduce TPC and pathogenic bacteria, the gamma irradiation were applied at 3.28- 4.43 kGy. The results indicated that the irradiation can reduce the TPC around 1.2 – 3.9 log cycles and eliminate pathogens bacteria in the product to make all of 15 samples qualified to the standard. The sensory evaluation was conducted in Namphrik Narok by using difference from control test to determine whether the consumers can differentiate between the non-irradiated and irradiated. The result showed that the consumers can significantly differentiate the color, odor and flavor (p<0.05). However, the preference test showed that there was no significant preferences at p>0.05. Both non-irradiated and irradiated were scored at 6.4 (slightly to moderately preference). Thus the gamma irradiation can be used as a tool to improve the microbiological qualities of the Namphrik Narok product without effecting the consumer preference. (paper)

  4. Preservation of crab meat by gamma irradiation

    International Nuclear Information System (INIS)

    Loaharanu, P.; Prompubesara, C.; Kraisorn, K.; Noochpramool, K.

    1972-01-01

    Fresh crab meat from swimming crab (Portunus pelagicus, Linn.) was irradiated at doses of 0.075, 0.15 and 0.25 Mrad and held at 3 0 C. The storage life of non-irradiated crab meat was approximately 7 days compared with 14 days for crab meat irradiated at 0.075 Mrad and 28 days for samples receiving 0.15 or 0.25 Mrad treatment. Total aerobic count, trimethylamine nitrogen, total volatile basic nitrogen, and ammonia contents were used as objective indices of freshness in comparison with sensory evaluation of the crab meat. All objective indices correlated well with the sensory judgement of the samples. The crab meat used in the study was heavily contaminated with microorganisms. Irradiation at 0.15 and 0.25 Mrad reduced approximately 2 log cycles in the total count. Acinetobacter (Achromobacter) was predominated in irradiated crab meat, especially after prolonged storage. High coagulase positive staphylococci count was detected in only non-irradiated crab meat

  5. Irradiation of spices and herbs

    International Nuclear Information System (INIS)

    Eiss, M.I.

    1983-01-01

    Gamma irradiation has been extensively studied as a means of reducing the microbial contamination of spices. Experiments indicate that spices, with water contents of 4.5-12%, are very resistant to physical or chemical change when irradiated. Since spices are used primarily as food flavoring agents, their flavor integrity must not be changed by the process. Sensory and food applications analysis indicate no significant difference between irradiated samples and controls for all spices tested

  6. Microbiological Quality of Mixed Vegetables Salad and Insuring its Safety by Irradiation

    International Nuclear Information System (INIS)

    Hammad, A.A.; Abu El-Nour, S.A.; Swailam, H.M.; Serag, M.S.; Mansour, F.A.

    2008-01-01

    Fifteen prepackaged mixed vegetables salad samples were collected from different local supermarkets. They were tested for their microbiological quality. TAPC of mix salad samples ranged from 2.5 x 10 5 to 7.0 x 10 7 cfu/g; LAB between 2.0 x 10 3 and 7.1 x 10 6 cfu/g; M and Y ranged from 1. 10 2 to 4.5 x 10 3 cfu/g. All tested mix salad samples contained coliform bacteria, E. coli and Ent. Faecalis. Staph. aureus was found in 12 (80%) samples, while A. hydrophila was found in all mix salad samples. L. monocytogenes was present in only two samples and Salmonella spp. was detected in only one sample. Mix salad samples were irradiated at 1, 2 and 3 kGy, and then stored at refrigeration temperature (4 degree C±1). Generally, all irradiation doses used reduced the initial TAPC, LAB and TM and Y and the reduction was proportional with irradiation dose. The optimum irradiation dose for irradiating mix salad was identified to be 3 kGy as no pathogens were detected in mix salad samples exposed to this irradiation dose. This irradiation dose had no adverse effect on physical and sensorial quality attributes of mix salad and extended its shelf-life to 15 days against only 7 days for unirradiated samples

  7. Slag recycling of irradiated vanadium

    International Nuclear Information System (INIS)

    Gorman, P.K.

    1995-01-01

    An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were carried out to determine if the slag did indeed remove the transmutation impurities from the irradiated vanadium

  8. In-situ high temperature irradiation setup for temperature dependent structural studies of materials under swift heavy ion irradiation

    International Nuclear Information System (INIS)

    Kulriya, P.K.; Kumari, Renu; Kumar, Rajesh; Grover, V.; Shukla, R.; Tyagi, A.K.; Avasthi, D.K.

    2015-01-01

    An in-situ high temperature (1000 K) setup is designed and installed in the materials science beam line of superconducting linear accelerator at the Inter-University Accelerator Centre (IUAC) for temperature dependent ion irradiation studies on the materials exposed with swift heavy ion (SHI) irradiation. The Gd 2 Ti 2 O 7 pyrochlore is irradiated using 120 MeV Au ion at 1000 K using the high temperature irradiation facility and characterized by ex-situ X-ray diffraction (XRD). Another set of Gd 2 Ti 2 O 7 samples are irradiated with the same ion beam parameter at 300 K and simultaneously characterized using in-situ XRD available in same beam line. The XRD studies along with the Raman spectroscopic investigations reveal that the structural modification induced by the ion irradiation is strongly dependent on the temperature of the sample. The Gd 2 Ti 2 O 7 is readily amorphized at an ion fluence 6 × 10 12 ions/cm 2 on irradiation at 300 K, whereas it is transformed to a radiation-resistant anion-deficient fluorite structure on high temperature irradiation, that amorphized at ion fluence higher than 1 × 10 13 ions/cm 2 . The temperature dependent ion irradiation studies showed that the ion fluence required to cause amorphization at 1000 K irradiation is significantly higher than that required at room temperature irradiation. In addition to testing the efficiency of the in-situ high temperature irradiation facility, the present study establishes that the radiation stability of the pyrochlore is enhanced at higher temperatures

  9. Application of gamma irradiation for storage potato

    International Nuclear Information System (INIS)

    Rezaee, M.; Almasi, M.

    2009-01-01

    Since deficiency of controlled store in Iran and environmental problems of chemical material the use of gamma irradiation to control sprouting and increase the length of storage time of potatoes has been proposed as an alternative to cold storage or the use of chemical sprout suppressants. In this study potatoes of Agria Variety were irradiated at a dose of 0.10 KGY and stored along with the unirradiated controls at 12±3°C for a period of more than 6 month from October to April .After 4 month of storage the sprouting ranged from 5 to 12% in irradiated potatoes and 45 to 74% in unirradiated samples and after 6 month the unirradiated potatoes were discarded because of heavy sprouting and rotting. The rot attack was approximately double in unirradiated samples. It was found that losses through dehydration were 10.3 to 15.1 % in the irradiated potatoes. Also a comparative study of reducing and non-reducing sugars, vitamin-C content, total sugar, starch and protein was carried out between unirradiated and irradiated samples. The results suggested the efficacy of Gamma irradiation for ensuring availability of the storing quality of potato during lean periods from October to April. (author)

  10. Explosive phenomena in heavily irradiated NaCl

    NARCIS (Netherlands)

    denHartog, HW; Vainshtein, DI; Matthews, GE; Williams, RT

    1997-01-01

    In heavily irradiated NaCl crystals explosive phenomena can be initiated during irradiation or afterwards when samples are heated to temperatures between 100 and 250 degrees C. During irradiation of NaCl Na and Cl-2 precipitates and void structures are produced along with the accumulation of stored

  11. Quality evaluation of garlic irradiated in Argentine and stored in Brazil

    International Nuclear Information System (INIS)

    Curzio, Osvaldo A.; Croci, Clara A.; Domarco, Rachel E.; Spoto, Marta H.F.; Blumer, Lucimara; Walder, Julio M.M.

    1997-01-01

    This work was undertaken to evaluate the quality of garlic Colorado, irradiated in Argentina and stored for long period of time under environmental conditions in Brazil. Two samples of 100 kg each were selected from high quality garlic harvested in December/1995 from a region close to the Universidad Nacional del Sur. At 30 days after harvesting one of the samples were irradiated with a dose of 60 Gy. Both samples, irradiated and non irradiated, were transported by road from the Laboratorio de Radioisotopos of the Universidad Nacional del Sur, Bahia Blanca, Argentina, to the Centro de Energia Nuclear na Agriculture (CENA-USP), Piracicaba, Sao Paulo, Brazil. The effects of irradiation on weigh loss , discard, germination and sensorial analysis were nonthly observed on CENA among 30and 180 days of storage. The evaluation of germination evidences the benefits of the radioinhibition process. The irradiated bulbs did not exhibit any intern bud, however the non-irradiated bulbs exhibit any intern bud, however the non-irradiated bulbs exhibit any intern bud, however the non-irradiated bulbs exhibit 100% of germination on the period of storage. At the end of the period of storage, the weigh loss of the irradiated garlic was smaller than the non-irradiate one. The percentage of discard, evaluated as intern germination, scatying and whitering, was 43% on the irradiated sample. The analysis of sensorial parameters shows no difference between irradiated and non-irradiated garlic, so irradaition did not affect the sensorial quality of the product. (author). 12 refs., 8 tabs

  12. Effect of irradiation on sensory quality of fermented spicy chicken feet

    International Nuclear Information System (INIS)

    Gao Meixu; Li Shurong; Pei Ying; Jiang Xiujie; Wang Zhidong; Deng Wenmin; Chen Xun; Huang Min; Chen Hao

    2010-01-01

    Irradiation could effectively control lactobacillus of fermented spicy chicken feet and extend its shelf life. Sensory evaluation standard of fermented spicy chicken feet was established to study the sensory change after irradiation according to related standards and research results. Color and shape (weight 30%), scent (weight 30%), texture and taste (weight 40%) were selected as sensory evaluation items. The sensory evaluation results after irradiation 3 days didn't show significance difference among control, 3, 5, 8 and 12 kGy irradiated samples, and the sensory evaluation score of 10 kGy irradiated sample was much higher then other sample groups. The results after irradiation 11d were almost as same as 3d results. It is indicated that the sensory quality of fermented spicy chicken feet would not destroyed by irradiation, and suitable dosage of irradiation may promote the sensory quality of fermented spicy chicken feet. (authors)

  13. Irradiation treatment of minimally processed carrots for ensuring microbiological safety

    Science.gov (United States)

    Ashraf Chaudry, Muhammad; Bibi, Nizakat; Khan, Misal; Khan, Maazullah; Badshah, Amal; Jamil Qureshi, Muhammad

    2004-09-01

    Minimally processed fruits and vegetables are very common in developed countries and are gaining popularity in developing countries due to their convenience and freshness. However, minimally processing may result in undesirable changes in colour, taste and appearance due to the transfer of microbes from skin to the flesh. Irradiation is a well-known technology for elimination of microbial contamination. Food irradiation has been approved by 50 countries and is being applied commercially in USA. The purpose of this study was to evaluate the effect of irradiation on the quality of minimally processed carrots. Fresh carrots were peeled, sliced and PE packaged. The samples were irradiated (0, 0.5, 1.0, 2.0, 2.5, 3.0 kGy) and stored at 5°C for 2 weeks. The samples were analyzed for hardness, organoleptic acceptance and microbial load at 0, 7th and 15th day. The mean firmness of the control and all irradiated samples remained between 4.31 and 4.42 kg of force, showing no adverse effect of radiation dose. The effect of storage (2 weeks) was significant ( P10) in all other irradiated samples(1.0, 2.0, 2.5 and 3.0 kGy) after 2 weeks storage. No coliform or E. coli were detected in any of the samples (radiated or control) immediately after irradiation and during the entire storage period in minimally processed carrots. A dose of 2.0 kGy completely controlled the fungal and bacterial counts. The irradiated samples (2.0 kGy) were also acceptable sensorially.

  14. Red Star Ruby (Sunrise) and blond qualities of Jaffa grapefruits and their influence on plasma lipid levels and plasma antioxidant activity in rats fed with cholesterol-containing and cholesterol-free diets.

    Science.gov (United States)

    Gorinstein, Shela; Leontowicz, Hanna; Leontowicz, Maria; Drzewiecki, Jerzy; Jastrzebski, Zenon; Tapia, María S; Katrich, Elena; Trakhtenberg, Simon

    2005-09-23

    Bioactive compounds of peels and peeled red Star Ruby (Sunrise) and blond qualities of Jaffa grapefruits were analyzed and their antioxidant potential was assessed. The dietary fibers were determined according to Prosky et al., the total polyphenol content by Folin-Ciocalteu method and measured at 765 nm, minerals and trace elements by atomic absorption spectrometer, phenolic and ascorbic acids by HPLC and the antioxidant potential by two different antioxidant assays (DPPH and beta-carotene linoleate model system). It was found that the contents of most studied bioactive compounds in both qualities are comparable. Only the contents of total polyphenols and flavonoids were higher in red grapefruits, but not significant. The antioxidant potentials of red peeled grapefruits and their peels were significantly higher than of blond peeled grapefruits and their peels (Pcholesterol added diet. In conclusion, both qualities of Jaffa grapefruits contain high quantities of bioactive compounds, but the antioxidant potential of red grapefruits is significantly higher. Diets supplemented with both qualities of Jaffa grapefruits improve the plasma lipid levels and increase the plasma antioxidant activity, especially in rats fed with cholesterol added diets. Jaffa grapefruits, especially their red Star Ruby quality, could be a valuable supplementation for diseases-preventing diets.

  15. Identification of irradiated crab using EPR

    Energy Technology Data Exchange (ETDEWEB)

    Maghraby, A. [Radiation Dosimetry Department, National Institute for Standards (NIS), Ministry of Scientific Research, Haram, 12211- Giza, P.O. Box: 136 (Egypt)]. E-mail: maghrabism@yahoo.com

    2007-02-15

    EPR spectroscopy is a fast and powerful technique for the identification of irradiated food. Crab exoskeleton was divided into six parts: dactyl, cheliped, carapace, apron, swimming legs, and walking legs. Samples of the exoskeleton were prepared and irradiated to Cs-137 gamma radiation in the range (1.156-5.365 kGy). EPR spectra of unirradiated as well as irradiated samples were recorded and analyzed. Response to gamma radiation was plotted for each part of the exoskeleton, dactyl was found to be the most sensitive part, followed by the apron (38%), cheliped (37%), walking legs (30%), swimming legs (24%), and carapace (21%) relative to the dactyl response.

  16. Identification of irradiated crab using EPR

    International Nuclear Information System (INIS)

    Maghraby, A.

    2007-01-01

    EPR spectroscopy is a fast and powerful technique for the identification of irradiated food. Crab exoskeleton was divided into six parts: dactyl, cheliped, carapace, apron, swimming legs, and walking legs. Samples of the exoskeleton were prepared and irradiated to Cs-137 gamma radiation in the range (1.156-5.365 kGy). EPR spectra of unirradiated as well as irradiated samples were recorded and analyzed. Response to gamma radiation was plotted for each part of the exoskeleton, dactyl was found to be the most sensitive part, followed by the apron (38%), cheliped (37%), walking legs (30%), swimming legs (24%), and carapace (21%) relative to the dactyl response

  17. Simulation model for electron irradiated IGZO thin film transistors

    Science.gov (United States)

    Dayananda, G. K.; Shantharama Rai, C.; Jayarama, A.; Kim, Hyun Jae

    2018-02-01

    An efficient drain current simulation model for the electron irradiation effect on the electrical parameters of amorphous In-Ga-Zn-O (IGZO) thin-film transistors is developed. The model is developed based on the specifications such as gate capacitance, channel length, channel width, flat band voltage etc. Electrical parameters of un-irradiated IGZO samples were simulated and compared with the experimental parameters and 1 kGy electron irradiated parameters. The effect of electron irradiation on the IGZO sample was analysed by developing a mathematical model.

  18. Spices, irradiation and detection methods

    International Nuclear Information System (INIS)

    Sjoeberg, A.M.; Manninen, M.

    1991-01-01

    This paper is about microbiological aspects of spices and microbiological methods to detect irradiated food. The proposed method is a combination of the Direct Epifluorescence Filter Technique (DEFT) and the Aerobic Plate Count (APC). The evidence for irradiation of spices is based on the demonstration of a higher DEFT count than the APC. The principle was first tested in our earlier investigation in the detection of irradiation of whole spices. The combined DEFT+APC procedure was found to give a fairly reliable indication of whether or not a whole spice sample had been irradiated. The results are given (8 figs, 22 refs)

  19. Irradiated ground beef: sensory and quality changes during storage under various packaging conditions

    International Nuclear Information System (INIS)

    Murano, P.S.; Murano, E.A.; Olson, D.G.

    1998-01-01

    Ground beef patties (irradiated with 2 kGy and nonirradiated) were packaged using oxygen permeable (polyolefin) or oxygen impermeable material (polyethylene). Samples were irradiated in air and stored in air; irradiated under vacuum and stored under vacuum; or irradiated under vacuum and stored in air. Changes in flavor, texture, juiciness or aftertaste were evaluated after either 1 or 7 days storage at -25 degrees C prior to cooking. Irradiated 'Vac/Air' samples were more tender, irradiated 'Vac' samples were more moist, and irradiated 'Air' samples had the least aftertaste. A 3 log10 reduction in total aerobic counts was detected immediately after irradiation. No difference in lipid oxidation was found within the first week of storage, regardless of packaging atmosphere. Shelf life of ground beef patties was extended 55 days at 4 degrees C

  20. Application of rapid microbiological screening methods for detection of irradiated frozen foods

    International Nuclear Information System (INIS)

    Hussain, A.A.; Rady, A.H.; ElBary, N.A.A.

    2003-01-01

    The exposure of food to ionizing radiation is being progressively used in many countries to, inactivate food pathogens, eradicate pests and extend shelf-life. To ensure free consumer choice, irradiated food. The direct epi fluorescent filter technique (DEFT) was applied as recent and rapid technique for determination of total bacterial count in irradiated minced chicken (2,4,6, and 8 kGy) as well as non-irradiated samples. Also aerobic plate count (APC) was used to determine the viable bacterial cells. A large significant differences between the profiteered DEFT and APC counts were obtained with the irradiated samples of each chicken and fish where the conventional plating gives a much lower values than the (DEFT) technique compared with non-irradiated samples. A highly correlation (r=0.99 and 1.00) were detected at 8 and 6 kGy with irradiated minced chicken and fish respectively. The Gram-negative bacteria belonging to (Enterobacteriaceae and fluorescence pseudomonas) showed very low count in the irradiated selected fish samples compared with control while the endotoxin selected fish samples compared with control while the endotoxin levels did not affect under the same conditions. Micro-gel electrophoresis indicated that gamma irradiation at 8 kGy can induce DNA damage in the cells of both minced chicken and fish where, some bands disappeared compared with the non-irradiated samples

  1. Keeping the quality of cows' butter by gamma-irradiation

    International Nuclear Information System (INIS)

    Rady, A.H.; Badr, H.M.

    2003-01-01

    This investigation aims to study the use of gamma irradiation for keeping the quality of cows' butter. Fresh butter samples were exposed to gamma irradiation at doses of 0, 2.5 and 5 kGy followed by refrigerated storage and the effects of these treatments on the microbiological aspects and lipid characteristics of butter samples were studied. Moreover, fatty acid profiles and unsaponifiable matter constituents were determined by gas chromatographic analysis, while the stability of butter was determined by rancimat. The results indicated that gamma irradiation at 2.5 kGy dose reduced the counts of total bacteria, lipolytic bacteria, coliforms, molds and yeasts, however, these counts gradually increased during cold storage. Also irradiation at 5 kGy dose greatly reduced the total bacterial count which gradually increased upon storage, while completely eliminated the Other determined microorganisms. Irradiation treatments increased the acid value and peroxide value of butter, while the iodine number was not altered. Moreover, gas chromatographic analysis showed that gamma irradiation slightly increased the total volatile fatty acids, total saturated fatty acids and total hydrocarbons, while slightly decreased the total unsaturated fatty acids and total sterols. In addition, irradiation of butter decreased its stability as determined by rancimat and upon storage of both irradiated and non irradiated butter samples, the acid value gradually increased, while a flexuous changes in the peroxide value were observed. The present study proved that 2.5 and 5 kGy gamma irradiation doses could keep the quality of cows' butter and increased its shelf life at 4 +/- 1degreeC for 8 and 12 weeks as compared to 4 weeks for non irradiated butter (based on the visual appearance of mold growth on the surface of samples) without any effects on its sensory properties [es

  2. Identification of gamma-irradiated papaya, melon and watermelon

    Science.gov (United States)

    Marín-Huachaca, Nélida S.; Mancini-Filho, Jorge; Delincée, Henry; Villavicencio, Anna Lúcia C. H.

    2004-09-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  3. Identification of gamma-irradiated papaya, melon and watermelon

    International Nuclear Information System (INIS)

    Marin-Huachaca, N.S.; Mancini-Filho, Jorge; Delincee, Henry; Villavicencio, A.L.C.H.

    2004-01-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a 60 Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0 kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment

  4. Identification of gamma-irradiated papaya, melon and watermelon

    Energy Technology Data Exchange (ETDEWEB)

    Marin-Huachaca, N.S.; Mancini-Filho, Jorge E-mail: jmancini@usp.br; Delincee, Henry E-mail: henry.delincee@bfe.uni-karlsruhe.de; Villavicencio, A.L.C.H. E-mail: villavic@net.ipen.br

    2004-10-01

    Ionizing radiation can be used to control spoilage microorganisms and to increase the shelf life of fresh fruits and vegetables in replacement for the treatment with chemical fumigants. In order to enforce labelling regulations, methods for detecting the irradiation treatment directly in the produce are required. Recently, a number of detection methods for irradiated food have been adopted by the Codex Comission. A rapid screening method for qualitative detection of irradiation is the DNA Comet Assay. The applicability of the DNA Comet Assay for distinguishing irradiated papaya, melon, and watermelon was evaluated. The samples were treated in a {sup 60}Co facility at dose levels of 0.0, 0.5, 0.75, and 1.0 kGy. The irradiated samples showed typical DNA fragmentation whereas cells from non-irradiated ones appeared intact. In addition to the DNA Comet Assay also the half-embryo test was applied in melon and watermelon to detect the irradiation treatment.

  5. Isolation of Enterobacter cowanii in tomatoes after gamma irradiation

    International Nuclear Information System (INIS)

    Vicalvi, M.C.V.; Solidonio, E.G.; Silva, M.A.; Colaco, W.; Silva, G.R. da; Sena, K.X.F.R de

    2013-01-01

    The tomato is one of the most consumed fruit in the world. Bacteria of the family Enterobacteriaceae are responsible for large outbreaks of gastroenteritis. Irradiation is a physical method which reduces waste by eliminating spoilage organisms in foods. The objective of this study was to identify and determine the resistance profile of micro-organisms of the family Enterobacteriaceae from irradiated tomatoes. Were used three batches each containing 80 tomatoes, and divided in control and irradiated. The samples were individually properly identified as the irradiation dose applied. The material was subjected to irradiation with gamma rays, for irradiating with a cobalt-60 source, using doses: 1.0, 1.5 and 2 kGy (6,060 kGy/h). For microbiological analysis tomatoes were cut out, and removing the shells to obtain samples weighing 25g. Each sample was transferred to an Erlenmeyer containing sterilized water, stirring the assembly mechanically. Aliquots of the wash waters were sown in differential and selective media. After reisolation, the colonies were subjected to Gram staining then performed biochemical tests for identification. The antibiotic susceptibility tests were performed according to CLSI (Clinical Laboratory Standard Institute). It was isolated three strains of Enterobacter cowanii in tomato samples irradiated with a dose of 1.0 kGy, without isolating the other doses. As for the resistance profile, the strains were resistant to Ampicillin identified. Gamma irradiation at a dose of 1.5 and 2 kGy was effective in tomatoes as well as the micro-organism isolated after irradiation showed no profile of multidrug resistance. (author)

  6. Irradiation Behavior and Post-Irradiation Examinations of an Acoustic Sensor Using a Piezoelectric Transducer

    International Nuclear Information System (INIS)

    Lambert, T.; Zacharie-Aubrun, I.; Hanifi, K.; Valot, Ch.; Fayette, L.; Rosenkantz, E.; Ferrandis, J.Y.; Tiratay, X.

    2013-06-01

    design as the one which has been irradiated. The comparison between both results highlights microstructural evolutions due to irradiation effect. Firstly, metallographic examinations of polished low-angle cross-section of the sensor were performed. The use of low-angle cross-section sample gives geometrical characteristics (macroscopic swelling measurements for instance) with a very good accuracy. This preparation induces a significant magnification of observed region of interest, especially for the acoustic coupling material whose thickness is very small. Optical microscopy on irradiated and non-irradiated samples provides microstructural information about a possible evolution during irradiation test. Secondly, X-ray diffraction measurements on both samples give information about crystalline phase behavior under irradiation. In addition with the important feedback acquired during the in-pile test, these examinations allow us to improve the acoustic sensor design for the next experiments. (authors)

  7. Efficient development of web applications for remote participation using Ruby on Rails

    International Nuclear Information System (INIS)

    Emoto, M.; Yoshida, M.; Iwata, C.; Inagaki, S.; Nagayama, Y.

    2010-01-01

    Large-scale experiments such as ITER require international collaboration, and remote participation plays an important role in carrying out such experiments. Web-based applications are useful tools for scientists participating in experiments remotely using personal computers. Since the participants typically download web-based applications to their computer each time they access the web servers, they do not need to install extra software in order to use these applications. In addition, the application developers do not need to distribute the latest program files each time they are modified, thus reducing maintenance costs for remote participation systems. For these reasons, we have been developing web-based applications for the LHD experiments at NIFS. In a previous study, we showed the benefits of using Ruby on Rails (RoR) to develop web-based applications for analysis code. We thought this approach would also be useful for developing applications for remote participation. Therefore, we have developed several web-based applications using RoR for participating in the LHD experiments. These applications include a data viewer and a scheduler of experiments. The main reason to adopt RoR for this purpose is its efficiency for developing web-based applications. For example, to develop a data viewer, we used an existing program running on an X-Windows System. Using RoR, we could minimize the modifications of the existing programs to add web interfaces. In this paper, we will report a web-based application developed using RoR for the LHD experiment. We will also discuss the benefits of using RoR in developing remote participation tools.

  8. Development of porous structures in GaSb by ion irradiation

    International Nuclear Information System (INIS)

    Jacobi, C.C.; Steinbach, T.; Wesch, W.

    2012-01-01

    Ion irradiation of GaSb causes not only defect formation but also leads to the formation of a porous structure. To study the behaviour of this structural modification, GaSb was irradiated with 6 MeV Iodine ions and ion fluences from 5 × 10 12 to 6 × 10 15 ions/cm 2 . The samples were investigated by step height measurements and scanning electron microscopy (SEM). Experiments were performed with two different procedures: (CI) Continuous Irradiation of samples followed by measurements of the step height in air and (SI) Stepwise Irradiation of samples with measurements of the step height in air between subsequent irradiations. Samples irradiated continuously, show a linear increase of the step height with increasing ion fluence up to 1.5 × 10 14 ions/cm 2 followed by a steeper, linear increase for higher ion fluences up to a step height of 32 μm. This swelling is induced by a formation of voids, and the two different slopes can be explained by a transformation from isolated voids to a rod like structure. For samples irradiated accordingly to procedure (SI), the step height shows the same behaviour up to an ion fluence of 1.5 × 10 14 ions/cm 2 resulting in a step height of ≈3 μm but then decreases with further irradiation. The latter effect is caused by a compaction of the porous structure.

  9. Toxicity Test on Malondialdehyde Content and Antioxidant Capacity of Irradiation Sterilization Rendang : In Vitro

    International Nuclear Information System (INIS)

    Zubaidah Irawati; Kamalita Pertiwi; Fransiska Rungkat Zakaria

    2010-01-01

    The safety of irradiated ethnic ready to eat food at high doses raises many questions, and recognized as one of great obstacles in the development of commercialization of food irradiation globally. People are still worried that food treated with irradiation would have induced radioactivity because free radical and its complex derivatives are formed in the irradiation process. Therefore, this study is needed to help understanding the effect of irradiated food on biological system in order to understand the possible effect to human body. The aimed of this research work was to secure the safety of irradiated food at high dose by conducting a toxicity assay using lymphocytes and erythrocytes human blood, and to determine antioxidant capacity of gamma - sterilized rendang at 45 kGy.The methods used were extraction and preparation of rending samples, culture medium preparation, lymphocytes isolation, the assays on lymphocytes proliferation, erythrocytes hemolysis,, antioxidant capacity, and malonaldehyde, respectively. The tested samples were irradiated at PATIR BATAN on 11 th November 2006 (sample A), on 14 th June 2007 (sample B), and “No Label” on 14 th June 2007 (sample C), respectively and non irradiated rending as control was also prepared. The results of proliferation assay showed that irradiated samples did neither inhibit nor induce proliferation significantly. Obviously, hemolysis rate of all samples showed increasing rate with increasing concentration or inversely correlated with dilution neither caused an increase in erythrocytes hemolysis rate nor inhibition in erythrocytes hemolysis significantly. Antioxidant capacity assay in irradiated samples showed higher value than in non-irradiated sample while irradiation treatment did not influence malonaldehyde content in rendang. (author)

  10. The irradiation effects and processing dose for pet foods decontamination

    International Nuclear Information System (INIS)

    Zhu Jiating; Feng Min; Liu Chunquan; Zhao Yongfu; Jin Yudong; Ji Ping; Ha Yiming; Gao Meixu; Li Shurong; Wang Feng; Zhou Hongjie

    2009-01-01

    The applied dose range of irradiation processing of 4 kinds of pet foods had been studied. More than 92% microorganisms was inactive at the irradiation dose of 4 kGy, while more than 99% was inactive at 6 kGy. The microorganism load of irradiated pet food by 8 kGy met the requirement of national standards. The 10 kGy irradiation could sterilize the treated pet food. Salmonella had not been checked in irradiated or unirradiated samples. When irradiation dose ranged 4-10 kGy, there was no significant difference on contents of moisture, fat, protein, coarse fiber, carbohydrates, minerals (not including Calcium) or amino acids between irradiated and un-irradiated pet food. There was also no significant change on sensory quality of irradiated samples within this dose range. It is concluded that the recommended irradiation processing dose range for pet foods is 4-10 kGy. (authors)

  11. Effects of irradiation and refrigeration on the nutrients and shelf-life of tilapia (Oreochromis niloticus)

    International Nuclear Information System (INIS)

    Siqueira, Alessandra Aparecida Zilio Cozzo de

    2001-01-01

    The objective of this study is to enhance the shelf-life of processed fish, combining ionizing radiation and refrigeration with minimal processing. The physical, chemical, nutritional and microbiological characteristics of the specie Tilapia nilotica (Oreochromis niloticus) were studied in eviscerated samples and in commercial cuts. The fish were separated into samples irradiated with 1.0, 2.2 and 5 kGy and non-irradiated samples. They were stored at temperatures ranging from 0.5 deg C to -2 deg C for 20 and 30 days. During storage, the level of moisture in the non-irradiated samples decreased and the levels of protein and lipid increased while the irradiated samples remained stable. The levels of pH, TVB-N and NPN increased in the non-irradiated samples but tended to remain stable in the irradiated fish samples. During storage, microbiological analyses for the presence of coliforms proved the efficiency of the irradiation process. The irradiated samples had a microbiological content below the levels established by the Brazilian seafood legislation, whereas the non-irradiated samples had a higher microbiological content and were not in conformity with the officially permitted levels. Salmonella spp. and Staphylococcus aureus were not detected. The levels of amino acids in muscles and fatty acids in oil remained stable in the irradiated fish stored samples but decreased in the non-irradiated ones. Lipid-oxidation, measured by the TBARS test, showed a tendency to increase when the dose of irradiation increased. The storage products after 30 days showed good acceptability for sensorial parameters, appearance, odour, color and texture, so it is possible to increase the shelf life of a minimally processed tilapia using combined irradiation and refrigeration. (author)

  12. Use of electron spin resonance technique for identifying of irradiated foods

    Energy Technology Data Exchange (ETDEWEB)

    El-Shiemy, S M E

    2008-07-01

    The present investigation was carried out to establish the electron spin resonance (ESR) technique for identifying of some irradiated foodstuffs, i.e. dried fruits (fig and raisin), nuts (almond and pistachio) and spices (fennel and thyme). Gamma rays were used as follows: 0, 1, 3 and 5 kGy were given for dried fruits, while 0, 2, 4 and 6 kGy were given for nuts. In addition, 0, 5, 10 and 15 kGy were given for spices. All treatments were stored at room temperature (25{+-}2 degree C) for six months to study the possibility of detecting its irradiation treatment by ESR spectroscopy. The obtained results indicated that ESR signal intensities of all irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation. So, all irradiated samples under investigation could be differentiated from unirradiated ones immediately after irradiation treatment. The decay that occur in free radicals which responsible of ESR signals during storage periods at ambient temperature showed a significant minimize in ESR signal intensities of irradiated samples. Therefore, after six months of ambient storage the detection was easily possible for irradiated dried fig with dose {>=} 3 kGy and for all irradiated raisin and pistachio (shell). Also, it was possible for irradiated fennel with dose {>=} 10 kGy and for irradiated thyme with dose {>=}15 kGy. In contrast, the identification of all irradiated samples of almond (shell as well as edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  13. Use of electron spin resonance technique for identifying of irradiated foods

    International Nuclear Information System (INIS)

    El-Shiemy, S.M.E

    2008-01-01

    The present investigation was carried out to establish the electron spin resonance (ESR) technique for identifying of some irradiated foodstuffs, i.e. dried fruits (fig and raisin), nuts (almond and pistachio) and spices (fennel and thyme). Gamma rays were used as follows: 0, 1, 3 and 5 kGy were given for dried fruits, while 0, 2, 4 and 6 kGy were given for nuts. In addition, 0, 5, 10 and 15 kGy were given for spices. All treatments were stored at room temperature (25±2 degree C) for six months to study the possibility of detecting its irradiation treatment by ESR spectroscopy. The obtained results indicated that ESR signal intensities of all irradiated samples were markedly increased correspondingly with irradiation dose as a result of free radicals generated by gamma irradiation. So, all irradiated samples under investigation could be differentiated from unirradiated ones immediately after irradiation treatment. The decay that occur in free radicals which responsible of ESR signals during storage periods at ambient temperature showed a significant minimize in ESR signal intensities of irradiated samples. Therefore, after six months of ambient storage the detection was easily possible for irradiated dried fig with dose ≥ 3 kGy and for all irradiated raisin and pistachio (shell). Also, it was possible for irradiated fennel with dose ≥ 10 kGy and for irradiated thyme with dose ≥15 kGy. In contrast, the identification of all irradiated samples of almond (shell as well as edible part) and pistachio (edible part) was impossible after six months of ambient storage.

  14. Temperature annealing of tracks induced by ion irradiation of graphite

    International Nuclear Information System (INIS)

    Liu, J.; Yao, H.J.; Sun, Y.M.; Duan, J.L.; Hou, M.D.; Mo, D.; Wang, Z.G.; Jin, Y.F.; Abe, H.; Li, Z.C.; Sekimura, N.

    2006-01-01

    Highly oriented pyrolytic graphite (HOPG) samples were irradiated by Xe ions of initial kinetic energy of 3 MeV/u. The irradiations were performed at temperatures of 500 and 800 K. Scanning tunneling microscopy (STM) images show that the tracks occasionally have elongated structures under high-temperature irradiation. The track creation yield at 800 K is by three orders of magnitude smaller compared to that obtained during room-temperature irradiation. STM and Raman spectra show that amorphization occurs in graphite samples irradiated at 500 K to higher fluences, but not at 800 K. The obtained experimental results clearly reveal that the irradiation under high temperature causes track annealing

  15. Irradiation of lettuce (Lactuca sativa. L.): microbiological and sensory aspects

    International Nuclear Information System (INIS)

    Tsuhako, Vanessa Provenzano

    2005-01-01

    The increasing demand for fresh foods have stimulated the marketing of minimally processed vegetables. However, these products maintain most of their natural microbiota even after being sanitized, including pathogenic microorganisms. Refrigerated storage allows the growth of psychotropic microorganisms and among them the pathogen Listeria monocytogenes. The ingestion of food contaminated with L. monocytogenes may represent a risk to pregnant women and their fetuses and to immunocompromised people. Non-thermal alternative processes for food preservation, such as irradiation, can reduce pathogenic and spoilage microorganism populations without impairing substantial changes in sensory, physical or chemical attributes. The aims of this research were to evaluate the effect of gamma radiation on L. monocytogenes artificially inoculated on minimally processed lettuce, to evaluate its effect on lettuce leaves through acceptance sensory test and to determine the irradiated vegetable shelf life through sensory and microbiological tests. A mixture of 4 types of lettuce (Iceberg, Boston, Loose-leaf and Red loose-leaf) were artificially inoculated with L. monocytogenes (7 log UFC/g lettuce) and then exposed to 0.3; 0.6; 0.9 and 1.2 kGy, under refrigeration. The DlO values for L. monocytogenes varied fram 0.18 to 0.21 kGy. Sensory and microbiological tests indicated that the shelf life of Iceberg lettuce stored at 7 deg C was 5 and 7 days for the irradiated and non-irradiated samples, respectively, and for the irradiated and non-irradiated Loose-leaf lettuce samples were 10 days. For the non-irradiated Boston sample, the shelf life was 3 days and for the Irradiated 7 days. Red loose-leaf showed 5 and 4 days of shelf lives for the irradiated and non-irradiated, respectively. Irradiated samples presented better microbiological quality than non-irradiated ones. The irradiation is feasible process to improve quality and safety of lettuce leaves. (author)

  16. Manufacture of electron beam irradiation vessel and its characteristics

    International Nuclear Information System (INIS)

    Kanazawa, Takao; Haruyama, Yasuyuki; Yotsumoto, Keiichi

    1992-05-01

    Electron beam irradiation vessel, which is used for the irradiation of samples under an inert or a vacuum atmosphere, is made by considering the temperature control during or after irradiation. The vessel was composed of the temperature controlable samples supporting plate, beam slit with water cooling plate and the insert of thermosensor. The four samples supporting plate was produced with the materials made up of aluminium, stainless steel (SUS304), and copper. The stainless steel supporting plate has a heater inside the cooling pipes for the high temperature treatment of samples without exposure to atmosphere after the irradiation. In this report, the temperature distribution and dose characteristics such as dose distribution and effects of backscattered electron were studied by using several supporting plate and the comparison of the experimental results with the simulated results was also carried out. (author)

  17. Comparison of three methods for detection of herbal food supplement irradiation

    DEFF Research Database (Denmark)

    Leth, Torben; Hansen, Hanne; Boisen, Flemming

    2006-01-01

    A survey for irradiation of 106 herbal food supplements was carried out in Denmark in 2003. The results from three methods, two screening methods and a specific method, were compared: Direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL) and the......A survey for irradiation of 106 herbal food supplements was carried out in Denmark in 2003. The results from three methods, two screening methods and a specific method, were compared: Direct epifluorescent filter technique/aerobic plate count (DEFT/APC), photostimulated luminescence (PSL......) and thermoluminescence (TL) standardised by Comite Europeen de Normalisation (CEN). Forty samples screened positive with the DEFT/APC method. However, the TL method could only confirm irradiation of 15 samples, 11 samples wholly irradiated and 4 samples with a minor irradiated ingredient. Thus, the DEFT/APC method gave...

  18. Aspects of Low Temperature Irradiation in Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Brune, D.

    1968-08-01

    Neutron irradiation of the sample while frozen in a cooling device inserted in a reactor channel has been carried out in the analysis of iodine in aqueous samples as well as of mercury in biological tissue and water. For the simultaneous irradiation of a large number of aqueous solutions the samples were arranged in a suitable geometry in order to avoid mutual flux perturbation effects. The influence of the neutron temperature on the activation process has been discussed. Potential applications of the low temperature irradiation technique are outlined

  19. Aspects of Low Temperature Irradiation in Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brune, D

    1968-08-15

    Neutron irradiation of the sample while frozen in a cooling device inserted in a reactor channel has been carried out in the analysis of iodine in aqueous samples as well as of mercury in biological tissue and water. For the simultaneous irradiation of a large number of aqueous solutions the samples were arranged in a suitable geometry in order to avoid mutual flux perturbation effects. The influence of the neutron temperature on the activation process has been discussed. Potential applications of the low temperature irradiation technique are outlined.

  20. High-water-base hydraulic fluid-irradiation experiments

    International Nuclear Information System (INIS)

    Bradley, E.C.; Meacham, S.A.

    1981-10-01

    A remote system for shearing spent nuclear fuel assemblies is being designed under the direction of the Consolidated Fuel Reprocessing Program (CFRP). The design incorporates a dual hydraulic fluid actuation system in which only one of the fluids, a high-water-base (HWBF), would be exposed to ionizing radiation and radioactive contamination. A commercially available synthetic, solution-type HWBF was selected as the reference. Single-sample irradiation experiments were conducted with three commercial fluids over a range of irradiation exposures. The physical and chemical properties of the irradiated HWBFs were analyzed and compared with unirradiated samples. In general, the results of the analyses showed increasing degradation of fluid properties with increasing irradiation dose. The results also indicated that a synthetic solution-type HWBF would perform satisfactorily in the remote shear system where irradiation doses up to 10 6 Gy (10 8 rad) are expected

  1. High-water-base hydraulic fluid-irradiation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, E.C.; Meacham, S.A.

    1981-10-01

    A remote system for shearing spent nuclear fuel assemblies is being designed under the direction of the Consolidated Fuel Reprocessing Program (CFRP). The design incorporates a dual hydraulic fluid actuation system in which only one of the fluids, a high-water-base (HWBF), would be exposed to ionizing radiation and radioactive contamination. A commercially available synthetic, solution-type HWBF was selected as the reference. Single-sample irradiation experiments were conducted with three commercial fluids over a range of irradiation exposures. The physical and chemical properties of the irradiated HWBFs were analyzed and compared with unirradiated samples. In general, the results of the analyses showed increasing degradation of fluid properties with increasing irradiation dose. The results also indicated that a synthetic solution-type HWBF would perform satisfactorily in the remote shear system where irradiation doses up to 10/sup 6/ Gy (10/sup 8/ rad) are expected.

  2. Microstructural characterization of second phase irradiated Zircaloy-4 particles

    International Nuclear Information System (INIS)

    Flores, Alejandra V.; Vizcaino, Pablo; Banchik, Abraham D.; Bozzano, Patricia B.; Versaci, Raul A.

    2007-01-01

    X-ray diffraction diagrams of neutron irradiated Zircaloy-4 were obtained at the LNLS with the aim to obtain bulk information about the amorphization process in which the Zircaloy-4 second phase particles (SPPs) undergoes due to neutron irradiation. Owing to the low concentration of the SPPs in the alloy (∼0.4 V %), no data regarding to the bulk were obtained until now. The synchrotron experiences allowed to detect five of the more intense lines of the phase C 14 (SPPs structure) in unirradiated Zircaloy-4: (110) θ, (103) θ, (112) θ, (201) θ and (004) θ in the 34 degrees ≤ θ2≤45 degrees Bragg angle range and others of minor intensity. The diagrams of the samples irradiated at moderate doses (1020n/cm 2 ) show these lines even in the as received samples. In contrast, none of these lines are observed for high fluence samples (∼1022neutrons/cm 2 ). In addition, in similar high fluence samples annealed 24 h or 72 h at 600 C degrees the intensity rises just at the 2q range where the C 14 lines were observed, showing a wide peak. That peak is interpreted as a result of the superposition of unresolved diffraction lines corresponding to the Zircaloy SPPs which are in a reconstitution process of crystallization. Analytical Electron Microscopy techniques were used, in order to study the effects on the Zircaloy-4 SPPs and compared with samples of the same material without irradiation. Spots in SAD patterns of non irradiated SPPS, evidences the presence of a C 14 structure, but in irradiated SSP SAD patterns evidences the beginning of an amorphization process. Another important feature to point out is the different Fe / Cr ratio presented in both irradiated and non irradiated SSPs. In non irradiated precipitates the Fe / Cr ratio is approximately 1.5, while in irradiated precipitates the Fe / Cr ratio becomes near 1.0. (author) [es

  3. Radical formation of irradiated α-alanine and N-acetyl alanine with heavy ion beams. Effects of the irradiation temperature

    International Nuclear Information System (INIS)

    Minegishi, Atsuko; Nagasaki, Jun; Mori, Wasuke; Amano, Chikara; Takagi, Shinji; Murakami, Takeshi; Kanai, Tatsuaki; Furusawa, Yoshiya; Iwata, Yoshiyuki

    2003-01-01

    The characteristics of irradiation with C290 MeV/u ion beams were investigated using X-band electron spin resonance (ESR) spectroscopy for a polycrystalline powder of L-α-alanine at from 77K to 310K. The formed main radicals at 190K∼310K were the deamino radical and the decarboxyl radical. Because of the first-derivative ESR, decarboxyl radical showed an expanded spectral width and a lower peak height because of its amino hydrogen and nitrogen than that of the same amount of deamino radical. The ESR of irradiated L-α-alanine predominantly indicates the spectrum of the deamino radical. On the irradiated, L-α-alanine at from 77K to 310K ESR showed 1:4:6:4:1 lines at 220K and at room temperature, which indicate that the methyl group of the radical was rotating. On the other hand, at 77K ESR the spectrum showed nearly 1:5:5:5:1 lines, like the teeth of a saw, on samples irradiated at 270K∼350K (range IV), and 1:4:6:4:1 lines for those irradiated at 180K∼260K (range II and III), respectively. It is considered that the radical conformation of the deamino radical is planar (most stable conformation) on an irradiated sample in range IV, and a pyramidal structure on the irradiated sample in ranges II and III. (author)

  4. Detection of irradiated food using photostimulated luminescence

    International Nuclear Information System (INIS)

    Malec-Czechowska, K.; Stachowicz, W.

    2005-01-01

    Detection of irradiated spices, dried mushrooms and flavour blends using photostimulated luminescence (PSL) is presented. PSL measurements were carried out as described in standard PN-EN 13751. A lower threshold (T 1 700 counts/60s) and an upper threshold (T 2 = 5000 counts/60s) were used to classify the sample. PSL intensities below the threshold were classified as from non-irradiated samples and PSL signals above the upper threshold were regarded from irradiated samples. Signal levels between the two thresholds were classified as intermediate, showing that further investigations are necessary. The PSL tests were carried out at Institute Nutritional Physiology, Federal Research Centre for Nutrition in Karlsruhe with a SURRAC PPSL Iradiated food screening system (SURRAC, Glasgow, UK). (author)

  5. Irradiation treatment of minimally processed carrots for ensuring microbiological safety

    International Nuclear Information System (INIS)

    Ashraf Chaudry, Muhammad; Bibi, Nizakat; Khan, Misal; Khan, Maazullah; Badshah, Amal; Jamil Qureshi, Muhammad

    2004-01-01

    Minimally processed fruits and vegetables are very common in developed countries and are gaining popularity in developing countries due to their convenience and freshness. However, minimally processing may result in undesirable changes in colour, taste and appearance due to the transfer of microbes from skin to the flesh. Irradiation is a well-known technology for elimination of microbial contamination. Food irradiation has been approved by 50 countries and is being applied commercially in USA. The purpose of this study was to evaluate the effect of irradiation on the quality of minimally processed carrots. Fresh carrots were peeled, sliced and PE packaged. The samples were irradiated (0, 0.5, 1.0, 2.0, 2.5, 3.0 kGy) and stored at 5 deg. C for 2 weeks. The samples were analyzed for hardness, organoleptic acceptance and microbial load at 0, 7th and 15th day. The mean firmness of the control and all irradiated samples remained between 4.31 and 4.42 kg of force, showing no adverse effect of radiation dose. The effect of storage (2 weeks) was significant (P 5 cfu/g, 3.0x10 2 and few colonies(>10) in all other irradiated samples(1.0, 2.0, 2.5 and 3.0 kGy) after 2 weeks storage. No coliform or E. coli were detected in any of the samples (radiated or control) immediately after irradiation and during the entire storage period in minimally processed carrots. A dose of 2.0 kGy completely controlled the fungal and bacterial counts. The irradiated samples (2.0 kGy) were also acceptable sensorially

  6. Study of the effects of low-fluence laser irradiation on wall paintings: Test measurements on fresco model samples

    Energy Technology Data Exchange (ETDEWEB)

    Raimondi, Valentina, E-mail: v.raimondi@ifac.cnr.it [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Cucci, Costanza [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Cuzman, Oana [Institute for the Conservation and Promotion of Cultural Heritage-National Research Council (CNR-ICVBC), Firenze (Italy); Fornacelli, Cristina [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Galeotti, Monica [Opificio delle Pietre Dure (OPD), Firenze (Italy); Gomoiu, Ioana [National University of Art, Bucharest (Romania); Lognoli, David [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Mohanu, Dan [National University of Art, Bucharest (Romania); Palombi, Lorenzo; Picollo, Marcello [‘Nello Carrara’Applied Physics Institute-National Research Council of Italy (CNR-IFAC), Firenze (Italy); Tiano, Piero [Institute for the Conservation and Promotion of Cultural Heritage-National Research Council (CNR-ICVBC), Firenze (Italy)

    2013-11-01

    Laser-induced fluorescence is widely applied in several fields as a diagnostic tool to characterise organic and inorganic materials and could be also exploited for non-invasive remote investigation of wall paintings using the fluorescence lidar technique. The latter relies on the use of a low-fluence pulsed UV laser and a telescope to carry out remote spectroscopy on a given target. A first step to investigate the applicability of this technique is to assess the effects of low-fluence laser radiation on wall paintings. This paper presents a study devoted to investigate the effects of pulsed UV laser radiation on a set of fresco model samples prepared using different pigments. To irradiate the samples we used a tripled-frequency Q-switched Nd:YAG laser (emission wavelength: 355 nm; pulse width: 5 ns). We varied the laser fluence from 0.1 mJ/cm{sup 2} to 1 mJ/cm{sup 2} and the number of laser pulses from 1 to 500 shots. We characterised the investigated materials using several diagnostic and analytical techniques (colorimetry, optical microscopy, fibre optical reflectance spectroscopy and ATR-FT-IR microscopy) to compare the surface texture and their composition before and after laser irradiation. Results open good prospects for a non-invasive investigation of wall paintings using the fluorescence lidar technique.

  7. Irradiation effect on animal feeds and feedstuffs

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    1983-10-01

    Aiming to secure the safety of animal feeds and develop the new resources, the effect of γ-irradiation on disinfection and the changes in components were investigated. Salmonellae and coliforms contaminating in animal feeds and feedstuffs were eliminated by 0.5 -- 0.6 Mrad and 0.5 -- 0.8 Mrad, and osmophilic moulds were sterilized by 0.7 -- 0.75 Mrad. From these results, it is concluded that the dose for disinfection of animal feeds is 0.8 Mrad. The main components were hardly changed by irradiation up to 5 Mrad, and the component changes in irradiated samples could be suppressed during storage while the components in unirradiated samples were markedly changed with the growth of osmophilic moulds. Histamine and lysinoalanine, which may cause the feed poisoning, were never accumulated in feedstuffs by irradiation. The nutritional value of chick feeds was not changed by 1.0 Mrad irradiation. From these results, it is considered that no problem for wholesomeness of animal feeds occurs by irradiation. Therefore, the irradiation is effective for disinfection and keeping the nutritional value of animal feeds during storage. Irradiation promotes the recovery of proteins in the wastewater by coagulation of proteins and improves the property of coagulants due to the degradation of polysaccharides. These results indicate that irradiation is effective to develop the new resources for animal feeds. (author)

  8. Studies on Microbiological and Biological Methods for Detection of Irradiated Food

    International Nuclear Information System (INIS)

    Ibrahim, H.M.A.

    2013-01-01

    The main aim of this study is to evaluate a microbiological and biological methods used for the detection of irradiated foods in Egypt. The microbiological methods included were shift in microflora load and direct epifluroescent filter technique compared with aerobic plate count (DEFT/APC), while the biological method was DNA comet assay. The selected foods were black, strawberry, fresh-and frozen-de boned chicken. The samples of these foods were exposed to different doses of gamma radiation according to the purpose of irradiation for each food. The results indicated that the characteristics of microbial population of all irradiated samples have been changed. The very lower count of viable bacterial count (APC) and mold and yeasts counts in the samples than the reported normal count as well as the absence of Gram- negative bacteria and Enterobacteriaceae group from these samples could be used as an indication for radiation treatment of these foods. The large difference between microbial counts obtained by DEFT test and that obtained by APC test could also be used for screening radiation treatment of these foods. Photographic and image analysis of DNA comet assay showed that irradiation of these foods caused damage to the food cells DNA (fragmentation) at different levels according to the doses used and kind of foods. This DNA damage can be followed or described by DNA comet assay test. On the basis of comet assay, the discrimination between unirradiated and irradiated food samples was very possible. In general the results showed that DEFT/APC method had the potential to detect irradiated food samples either at zero time of storage or throughout the storage period post- irradiation. DNA comet assay as a rapid, simple and inexpensive screening test approved to be successful for detection of irradiated food samples under investigation. Determination of rough applied irradiation dose is possible if photographic analysis is combined with image analysis

  9. Irradiation effects in hydrated zirconium molybdate

    Energy Technology Data Exchange (ETDEWEB)

    Fourdrin, C., E-mail: chloe.fourdrin@polytechnique.edu [CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91 191 Gif-sur-Yvette (France); CEA Saclay, DSM/IRAMIS/SIS2M-UMR 3299/Lrad, 91 191 Gif-sur-Yvette (France); Esnouf, S. [CEA Saclay, DSM/IRAMIS/SIS2M-UMR 3299/Lrad, 91 191 Gif-sur-Yvette (France); Dauvois, V. [CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91 191 Gif-sur-Yvette (France); Renault, J.-P. [CEA Saclay, DSM/IRAMIS/SIS2M-UMR 3299/Lrad, 91 191 Gif-sur-Yvette (France); Venault, L. [CEN Valrho, DEN/DRCP/SCPS/LC2A, 30 207 Bagnols-sur-Ceze (France); Tabarant, M. [CEA Saclay, DEN/DANS/DPC/LRSI, 91 191 Gif-sur-Yvette (France); Durand, D. [CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91 191 Gif-sur-Yvette (France); Cheniere, A. [CEA Saclay, DEN/DANS/DPC/LRSI, 91 191 Gif-sur-Yvette (France); Lamouroux-Lucas, C. [CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91 191 Gif-sur-Yvette (France); Cochin, F. [AREVA NC Tour, AREVA, 92 084 Paris La Defense cedex (France)

    2012-07-15

    Hydrated zirconium molybdate is a precipitate formed during the process of spent nuclear fuel dissolution. In order to study the radiation stability of this material, we performed gamma and electron irradiation in a dose range of 10-100 kGy. XRD patterns showed that the crystalline structure is not affected by irradiation. However, the yellow original sample exhibits a blue-grey color after exposure. The resulting samples were analyzed by means of EPR and diffuse reflectance spectroscopy. Two sites for trapped electrons were evidenced leading to a d{sup 1} configuration responsible for the observed coloration. Moreover, a third defect corresponding to a hole trapped on oxygen was observed after electron irradiation at low temperature.

  10. Brazilian Consumer views on food irradiation

    NARCIS (Netherlands)

    Behrens, J.H.; Barcellos, M.N.; Frewer, L.J.; Nunes, T.P.; Landgraf, M.

    2009-01-01

    This study investigated the consumer attitude to food irradiation in São Paulo, Brazil, through a qualitative research perspective. Three focus groups were conducted with 30 consumers, responsible for food choices and purchases. Both irradiated and nonirradiated food samples were served in the

  11. Shelf-life extension and improvement of the microbiological quality of smoked salmon by irradiation

    International Nuclear Information System (INIS)

    Hammond, A.A.I.; El-Mongy, T.M.

    1992-01-01

    Cold-smoked salmon locally available was irradiated at 2 and 4 kGy. Irradiated and unirradiated samples were stored at refrigeration temperature (2-3 degrees C). Microbiological and sensory qualities were studied immediately after irradiation and during storage. Irradiation at 2 kGy caused a great reduction in all the tested microbial population, thus improving the hygienic quality of smoked salmon to meet the microbiological limits for the top-grade quality. Moreover, irradiated samples at 4 kGy were free from coliform bacteria, fecal streptococci and Staph. aureus over the entire storage period. Unirradiated samples reached the maximum accepted mesophilic plate count after only one month of storage, while those irradiated at 2 and 4 kGy reached this level after 3 and 4 months, respectively. No differences in sensory qualities were found by the taste panel between unirradiated samples and those irradiated at 2 kGy, but they observed a distinct loss in normal cherry red color of the samples irradiated at 4 kGy

  12. Development of shelf-stable meat sausages using gamma irradiation

    International Nuclear Information System (INIS)

    Seri Chempaka Mohd Yusof; Muhammad Lebai Juri; Mariani Deraman

    2006-01-01

    Irradiation techniques have been applied in development of ready to eat or shelf stable sausages. These sausages can be eaten directly without the need for prior heating or cooking procedure and displayed in the room temperature on the shelves of the retailers without frozen facilities. This study was designed to investigate the acceptability and microbial status of packed ready to eat sausages that had been sterilized using gamma irradiation at MINTec-Sinagama. Packed pre-cooked sausage samples (sealed in plastic-polyethylene individually) were irradiated with different doses of 2.5 kGy, 3.5 kGy and 5.5 kGy. Acceptability of the sausages was determined through sensory evaluation by 30 members of untrained panelists comprising of staffs of MINT. A 5 points hedonic rating scale was used. The attributes evaluated were rancidity, texture, chewiness, juiciness, aroma, colour, shape and overall acceptance. Samples irradiated with doses 3.5 kGy were the most acceptable followed by samples irradiated with doses 2.5 kGy and 5.5 kGy respectively. Irradiation with doses up to 2.5 kGy will virtually eliminate disease-causing microorganisms and pathogens. The total microbial count, detection of Salmonella, Escherichia coli, Staphylococcus aureus and fungi in these samples were determined and discussed. (Author)

  13. Gamma-irradiation of tomatoes

    International Nuclear Information System (INIS)

    Tencheva, S.; Todorov, S.

    1975-01-01

    The influence of gamma-ray on tomatoes picked in a pink-red ripening stage, good for consumption, is studied. For that purpose tomatoes of ''Pioneer 2'' variety packed in perforated 500 g plastic bags were irradiated on a gamma device (Cobalt-60) at a dose power of 1900 rad/min with doses 200 or 300 krad. Samples were stored after irradiation at room temperature (20 - 22sup(o)C). Microbiological studies demonstrated that 44 resp. 99.96 per cent of the initial number of microorganisms was destroyed after irradiation with 200 resp. 300 krad. The time required for the number of microorganisms to be restored was accordingly increased. Irradiation delayed tomato ripening by 4 to 6 days, demonstrable by the reduced content of the basic staining substances - carotene and licopine. Immediately after irradiation the ascorbic acid content was reduced by an average of 13 per cent. After 18 days the amount of ascorbic acid in irradiated tomatoes was increased to a higher than the starting level, this is attributed to reductone formation during irradiation. The elevated total sugar content shown to be invert sugar was due to further tomato ripening. (Ch.K.)

  14. Dielectric properties of proton irradiated PES

    International Nuclear Information System (INIS)

    Shah, Nilam; Singh, N.L.; Singh, K.P.

    2005-01-01

    Polyethersulfone films were irradiated with 3 MeV proton beam at fluences ranging from 10 13 to 10 15 ions/cm 2 . AC electrical properties of irradiated samples were studied in the frequency range 100 Hz to 1MHz by LCR meter. There is an exponential increase in conductivity with frequency but the effect of irradiation is not significant. The dielectric loss/constant are observed to change with fluence. (author)

  15. The Influence of Irradiation Regimes on Retention Hydrogen Isotopes in Structural Materials

    International Nuclear Information System (INIS)

    Zaluzhnyi, A.

    2007-01-01

    Full text of publication follows: In the present work was investigated the influence of irradiation regimes on retention hydrogen isotopes in samples of austenitic steel during heating. The samples of studied materials were irradiated both in the reactor and by hydrogen isotopes ions of different energies and fluencies bombardment in an accelerator. Kinetic of hydrogen release from the samples worked with deuterium plasma was investigated. The following results were obtained. Heating the irradiate d samples of steel (irradiated in the reactor or by hydrogen isotopes ions bombardment), which have been kept in normal temperature during quite a long period after the irradiation, a shift of the diffusion peak of hydrogen release to higher temperatures, comparing to no irradiated samples, was observed. It means that atoms of hydrogen in the irradiated sample were caught by radiation defects, which are very effective as traps for hydrogen atoms till quite high temperatures (700 K). The worked out analysis of the received results supposes that vacancy complexes. On thermodesorption curves of hydrogen release from irradiated samples of austenitic steels a high temperature peak (900-1000 K) was observed because of dissociation of hydrogen containing compounds in micro pores. During investigations of hydrogen release from irradiated samples of austenitic steel, after it had been saturated with hydrogen plasma, abnormally big blisters were registered with cover thickness of about 1 mkm. Three peaks were observed on the thermodesorption curves of hydrogen release from irradiated samples, contained blisters. The low temperature spike (∼500 K) was showed to correspond to hydrogen release because of its resolution from blisters, where it was in molecular form. The high temperature peak (∼900 K) corresponds to hydrogen release from dissociating blisters, which contain hydrocarbons. The mechanism of abnormal blisters generation is offered. Inasmuch methane is not soluble in

  16. Irradiation enhanced diffusion and irradiation creep tests in stainless steel alloys

    International Nuclear Information System (INIS)

    Loelgen, R.H.; Cundy, M.R.; Schuele, W.

    1977-01-01

    A review is given of investigations on the rate of phase changes during neutron and electron irradiation in many different fcc alloys showing either precipitation or ordering. The diffusion rate was determined as a function of the irradiation flux, the irradiation temperature and the irradiation dose. It was found that the radiation enhanced diffusion in all the investigated alloys is nearly temperature independent and linearly dependent on the flux. From these results conclusions were drawn concerning the properties of point defects and diffusion mechanisms rate determining during irradiation, which appears to be of a common nature for fcc alloys having a similar structure to those investigated. It has been recognized that the same dependencies which are found for the diffusion rate were also observed for the irradiation creep rate in stainless steels, as reported in literature. On the basis of this obervation a combination of measurements is suggested, of radiation enhanced diffusion and radiation enhanced creep in stainless steel alloys. Measurements of radiation enhanced diffusion are less time consuming and expensive than irradiation creep tests and information on this property can be obtained rather quickly, prior to the selection of stainless steel alloys for creep tests. In order to investigate irradiation creep on many samples at a time two special rigs were developed which are distinguished only by the mode of stress applied to the steel specimens. Finally, a few uniaxial tensile creep tests will be performed in fully instrumented rigs. (Auth.)

  17. Effects of low-level gamma irradiation on the characteristics of fermented pork sausage during storage

    International Nuclear Information System (INIS)

    Kim, I.S.; Jo, C.; Lee, K.H.; Lee, E.J.; Ahn, D.U.; Kang, S.N.

    2012-01-01

    The effect of gamma irradiation (0.5, 1, 2, and 4 kGy) on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. At Day 0 of irradiation, the pH, redness (CIE a ⁎ ), yellowness (CIE b ⁎ ), 2-thiobarbituric acid-reactive substances (TBARS) and volatile basic nitrogen (VBN) values of samples irradiated at 2 and 4 kGy were higher (p ⁎ values (lightness) were lower than those of the non-irradiated control (p ⁎ , CIE a ⁎ and CIE b ⁎ -value of samples were not significantly influenced by irradiation. The CIE a ⁎ , and CIE b ⁎ -values of samples irradiated at 2 and 4 kGy decreased with the increase of storage time. The VBN, TBARS, and CIE L ⁎ -values of samples irradiated at 4 kGy were not changed significantly during refrigerated storage for 90 days (p>0.05). The total plate counts (TPC) and lactic acid bacteria (LAB) in the samples irradiated at 4 kGy were significantly lower (p<0.01) than those with lower irradiation doses. At the end of storage, the TPC, coliform, and LAB in the samples were not increased after irradiation at 1, 0.5 and 1 kGy, respectively. TPC and LAB were not detected in samples irradiated at 4 kGy at Day 90. In addition, no coliform bacteria were found in samples irradiated at 1 kGy during refrigerated storage. Sensory evaluation indicated that the rancid flavor of samples irradiated at 4 kGy was significantly higher, but aroma and taste scores were lower than those of the control at Day 3 of storage. Irradiation of dry fermented sausages at 2 kGy was the best conditions to prolong the shelf-life and decrease the rancid flavor without significant quality deterioration. - Highlights: ► Effect of gamma irradiation on the quality of vacuum-packaged dry fermented sausages during refrigerated storage was evaluated. ► At Day 90, the TPC, coliform, and LAB in the dry fermented sausages were not increased after irradiation at 2, 0.5 and 4 kGy, respectively. ► TPC and LAB were not detected in

  18. Detecting irradiation of seeds using microgel electrophoresis (a collaborative trial)

    International Nuclear Information System (INIS)

    Cerda, H.; Haine, H.E.; Jones, J.L.

    1995-06-01

    Preservation of certain foods by irradiation is permitted in the United Kingdom. However, all irradiated foods must be labelled as such, to ensure consumer choice. To help enforce labelling, a variety of methods have been developed for distinguishing between irradiated and non-irradiated foods. In preliminary trials, microgel electrophoresis -a simple method of assessing DNA damage - has shown considerable promise in this respect. This report describes microgel electrophoresis, and details results obtained in a blind trial carried out in collaboration with the Swedish University of Agricultural Sciences. Microgel electrophoresis facilitates analysis of the leakage of DNA from cells extracted from food material. In irradiated samples, the DNA is fragmented and will leak from cells in an electric current. This leakage can be seen as a 'comet' when the stained gel is viewed with a microscope. The size and shape of the comet can be used to estimate the irradiation dose administered to the sample. In non-irradiated samples the DNA is less fragmented, will tend not to leak from the cells and will not form a comet. (author)

  19. Chemical aspects of irradiated mangoes

    International Nuclear Information System (INIS)

    Singh, H.

    1990-06-01

    Mango is an important and very popular tropical fruit. Because of its short shelf life, however, its use is restricted to the areas of production. Since mango is a climacteric fruit, it is possible to extend its shelf life by delaying the ripening process and senescence by irradiation. The ripening process is very complex: it appears that the radiation-induced delay in ripening may be mediated through the inhibition of the enzyme(s) involved in ethylene production. The dose required for shelf-life extension is ≤1.5 kGy. Higher doses can lead to scalding, flesh darkening and development of hollow pockets. This review focuses on the chemical aspects of radiation-induced shelf-life extension of mangoes. At the low irradiation doses required for this shelf-life extension (≤1.5 kGy), the chemical effects are negligible. Irradiation does not affect the carotenoid levels, and has only a minor effect on the vitamin C level in a few mango varieties. No significant differences in the free and total (hydrolyzed) amino acids, or the protein content of Kent mangoes, have been detected between irradiated and unirradiated samples. During ripening of the mangoes the reducing sugar and the total sugar levels increase, but in the majority of the mango varieties these levels remain very similar in irradiated and unirradiated samples. There are some differences in the volatile compounds between irradiated and unirradiated Kent mangoes; however, these differences have no apparent effect on the taste and flavor of the irradiated mangoes

  20. The analysis and attribution of the time-dependent neutron background resultant from sample irradiation in a SLOWPOKE-2 reactor

    International Nuclear Information System (INIS)

    Sellers, M.T.; Corcoran, E.C.; Kelly, D.G.

    2013-01-01

    The Royal Military College of Canada (RMCC) has commissioned a Delayed Neutron Counting (DNC) system for the analysis of special nuclear materials. A significant, time-dependent neutron background with an initial maximum count rate, more than 50 times that of the time-independent background, was characterised during the validation of this system. This time-dependent background was found to be dependent on the presence of the polyethylene (PE) vials used to transport the fissile samples, yet was not an activation product of vial impurities. The magnitude of the time-dependent background was found to be irradiation site specific and independent of the mass of PE. The capability of RMCC's DNC system to analyze the neutron count rates in time intervals 235 U contamination was present on each irradiated vial. However, Inductively Coupled Plasma-Mass Spectroscopy measurements of material leached from the outer vial surfaces after their irradiations found only trace amounts of uranium, 0.118 ± 0.048 ng of 235 U derived from natural uranium. These quantities are insufficient to account for the time-independent background, and in fact could not be discriminated from the noise associated with time-independent background. It is suggested that delayed neutron emitters are deposited in the vial surface following fission recoil, leaving the main body of uranium within the irradiation site. This hypothesis is supported by the physical cleaning of the site with materials soaked in distilled water and HNO 3 , which lowered the background from a nominal 235 U mass equivalent of 120 to 50 ng per vial. (author)

  1. Effect of neutron irradiation on select MAX phases

    International Nuclear Information System (INIS)

    Tallman, Darin J.; Hoffman, Elizabeth N.; Caspi, El’ad N.; Garcia-Diaz, Brenda L.; Kohse, Gordon; Sindelar, Robert L.; Barsoum, Michel W.

    2015-01-01

    Herein we report on the effect of neutron irradiation – of up to 0.1 displacements per atom at 360(20) °C or 695(25) °C – on polycrystalline samples of Ti 3 AlC 2 , Ti 2 AlC, Ti 3 SiC 2 and Ti 2 AlN. Rietveld refinement of X-ray diffraction patterns of the irradiated samples showed irradiation-enhanced dissociation into TiC of the Ti 3 AlC 2 and Ti 3 SiC 2 phases, most prominently in the former. Ti 2 AlN also showed an increase in TiN content, as well as Ti 4 AlN 3 after irradiation. In contrast, Ti 2 AlC was quite stable under these irradiation conditions. Dislocation loops are seen to form in Ti 2 AlC and Ti 3 AlC 2 after irradiation at 360(20) °C. The room temperature electrical resistivity of all samples increased by an order of magnitude after irradiation at 360(20) °C, but only by 25% after 695(25) °C, providing evidence for the MAX phases’ dynamic recovery at temperatures as low at 695(25) °C. Based on these preliminary results, it appears that Ti 2 AlC and Ti 3 SiC 2 are the more promising materials for high-temperature nuclear applications

  2. Effect of irradiation and storage on physico-chemical characteristics of garlic

    International Nuclear Information System (INIS)

    Wahid, M.; Mazullah; Khan, S.; Shah, A.H.

    1990-01-01

    Garlic bulbs (cv. G.S.I.) were irradiated at 0.05, 0.10, 0.15 or 0.20 kGy using 60 Co and stored in wooden crates for 4 months at ambient temperature (20-37°C, 50-80% RH) or low temperature (10°, 80-90% RH). Samples were monitored for sprouting, rot and weight loss. Consumer acceptability and acid value were determined throughout storage. Sprouting was apparent in control (non-irradiated) samples after 4 and 10 weeks' storage at low and ambient temperature, respectively, and reached 100 and 69% after 16 weeks' storage at low and ambient temperature, respectively. Irradiation inhibited sprouting at both temperatures. Percentage decay [unspecified] was lower in irradiated samples than in controls, which showed 31.7% and 52.9% decay, respectively, after 16 weeks' storage at ambient and low temperature. Weight loss increased from 0.2 to 28.3% and from 0.3 to 31.5% in control samples at low and ambient temperature, respectively, between 2 and 16 weeks' storage. Weight loss was less in irradiated samples. Sensory tests showed that irradiated samples retained colour, texture and odour compared with controls. There was a gradual and significant increase (from 0.448 to 2.246 mg KOH/100 g edible portion of sample) in the acid value of controls during storage. Lower doses of irradiation and storage temperature had an irregular effect on the acid value but the highest dose increased the acid value. It was concluded that irradiation had no deleterious effects on the storage properties of garlic and that a dose of 0.05 kGy could be considered cost-effective. (author)

  3. Detection of irradiation of strawberries by determining their microbial characteristics

    International Nuclear Information System (INIS)

    Tamminga, S.K.; Beumer, R.R.; Kampelmacher, E.H.

    1978-01-01

    A system was elaborated to determine whether strawberries have been irradiated, using 3 criteria, namely the number of Enterobacteriaceae, the percentage of yeasts on total microflora (or total absence of microorganisms) and the number of Pseudomonas. The higher the numbers of Enterobacteriaceae and/or Pseudomonas, the lower the probability that the strawberries have been irradiated. The higher the yeast percentage, the more the conclusion is justified that irradiation has taken place. The same holds true for total absence of microorganisms. By combining results for the 3 criteria an identification scheme was drawn up that would have led to 189 correct decisions (92.2%) on 205 samples (102 irradiated with 200krad, 103 unirradiated). In only 3 samples (1.5%) the combination of properties resembled that generally shown by the opposite group in such a way that they would have been classified in the wrong category. Some combinations of results for the 3 criteria were found in about equal numbers for both irradiated and unirradiated samples. These samples and others showing contradictory results, totalling 13 samples (6.3%), had to be placed in a separate 'intermediate' category, about which no opinion could be given. The only possibility in such cases is to investigate new samples. Sixty of the samples were investigated without the investigators knowing whether the samples had been irradiated; 56 of them would have been classified in the right category with the help of the scheme made up using the previous data; the remaining 4 had to be classified in the intermediate category. (author)

  4. Advanced Oxidation Treatment of Drinking Water and Wastewater Using High-energy Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Abbas Behjat

    2007-03-01

    Full Text Available Application of electron beam as a strong oxidation method for disinfection of drinking water and wastewater has been investigated. Drinking water samples were prepared from wells in rock zones in Yazd Province. Wastewater samples were collected from Yazd Wastewater Treatment Plant. Samples were irradiated by 10 MeV electron beam accelerator at Yazd Radiation Processing Center. The irradiation dose range varied from 0.5-5 kGy. Biological parameters and microbial agents such as aerobic mesophiles and coliforms including E. coli count before and after irradiation versus irradiation dose were obtained using MPN method. The data obtained from irradiated water and wastewater were compared with un-irradiated (control samples. The results showed a removal of 90% of all microorganisms at irradiation doses below 5 kGy, suggesting electron beam irradiation as an effective method for disinfection of wastewater.

  5. Effect of irradiation temperature on microstructural changes in self-ion irradiated austenitic stainless steel

    Science.gov (United States)

    Jin, Hyung-Ha; Ko, Eunsol; Lim, Sangyeob; Kwon, Junhyun; Shin, Chansun

    2017-09-01

    We investigated the microstructural and hardness changes in austenitic stainless steel after Fe ion irradiation at 400, 300, and 200 °C using transmission electron microscopy (TEM) and nanoindentation. The size of the Frank loops increased and the density decreased with increasing irradiation temperature. Radiation-induced segregation (RIS) was detected across high-angle grain boundaries, and the degree of RIS increases with increasing irradiation temperature. Ni-Si clusters were observed using high-resolution TEM in the sample irradiated at 400 °C. The results of this work are compared with the literature data of self-ion and proton irradiation at comparable temperatures and damage levels on stainless steels with a similar material composition with this study. Despite the differences in dose rate, alloy composition and incident ion energy, the irradiation temperature dependence of RIS and the size and density of radiation defects followed the same trends, and were very comparable in magnitude.

  6. Effect of gamma irradiation on the photoluminescence of porous silicon

    Energy Technology Data Exchange (ETDEWEB)

    Elistratova, M. A., E-mail: Marina.Elistratova@mail.ioffe.ru; Romanov, N. M. [Peter the Great St. Petersburg Polytechnic University (Russian Federation); Goryachev, D. N. [Russian Academy of Sciences, Ioffe Institute (Russian Federation); Zakharova, I. B. [Peter the Great St. Petersburg Polytechnic University (Russian Federation); Sreseli, O. M. [Russian Academy of Sciences, Ioffe Institute (Russian Federation)

    2017-04-15

    The effect of gamma irradiation on the luminescence properties of porous silicon produced by the electrochemical technique is studied. Changes in the photoluminescence intensity between irradiation doses and over a period of several days after the last irradiation are recorded. The quenching of photoluminescence at low irradiation doses and recovery after further irradiation are registered. It is found that porous silicon is strongly oxidized after gamma irradiation and the oxidation process continues for several days after irradiation. It is conceived that the change in the photoluminescence spectra and intensity of porous silicon after gamma irradiation is caused by a change in the passivation type of the porous surface: instead of hydrogen passivation, more stable oxygen passivation is observed. To stabilize the photoluminescence spectra of porous silicon, the use of fullerenes is proposed. No considerable changes in the photoluminescence spectra during irradiation and up to 18 days after irradiation are detected in a porous silicon sample with a thermally deposited fullerene layer. It is shown that porous silicon samples with a deposited C{sub 60} layer are stable to gamma irradiation and oxidation.

  7. Preparation and characterization of pyrromethene-567 dye-doped polymer samples using Gamma Irradiation Polymerization Method (GIPM)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghamdi, Attieh A., E-mail: aaaalghamdi4@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Jeddah (Saudi Arabia); Mahrous, Eiman M. [Taibah University, Department of Physics, Madinah (Saudi Arabia); Al-Enizi, Abdullah M. [King Saud University, Department of Chemistry, Riyadh (Saudi Arabia); Azam, Ameer [Center of Nanotechnology, King Abdulaziz University, Jeddah (Saudi Arabia)

    2015-01-15

    Dye-doped polymer gain media laser samples of pyrromethene-567 in a mixture with methyl methacrylate and 2-hydroxyethyl methacrylate copolymer have been prepared and synthesized by the Conventional Thermal Polymerization Method (CTPM) using an oven, and by the Gamma Irradiation Polymerization Method (GIPM) using Cobalt-60 ({sup 60}Co). Physical properties comprising absorption molar coefficients, absorption cross sections, fluorescence quantum yields, fluorescence life times, and emission cross sections were determined and calculated from the measured absorption and emission spectra. The efficiency and photo-stability of samples fabricated by both methods were measured and compared. The time required for synthesis was reduced by 90% using the GIPM. Complete polymerization of the GIPM sample was found to be at 7 kGy. Further, the GIPM produces high laser damage resistance material, which might be attributed to the highly dense polymeric network structure formed as a result of the effect of gamma radiation on MMA and HEMA monomers. - Highlights: • Samples of PM-567 in a mixture with MMA/HEMA were synthesized by the GIPM. • The time required for synthesis was reduced by 90% using the GIPM. • Complete polymerization of the GIPM sample was at 7 kGy. • The laser media produced is fast and free of contamination that gives high purity material. • The GIPM produced a high laser damage resistance material.

  8. Irradiation and testing of compact ignition tokamak toroidal field coil insulation materials

    International Nuclear Information System (INIS)

    Kanemoto, G.K.; Sherick, M.J.; Sparks, D.C.

    1990-05-01

    This report documents the results of an irradiation and testing program performed on behalf of Martin Marietta Energy Systems, Inc. in support of the Compact Ignition Tokamak Research and Development program. The purpose of the irradiation and testing program was to determine the effects of neutron and gamma irradiation on the mechanical and electrical properties of candidate toroidal field coil insulation materials. Insulation samples were irradiated in the Advanced Test Reactor (ATR) in a large I-hole. The insulation samples were irradiated within a lead shield to reduce exposure to gamma radiation to better approximate the desired ration of neutron to gamma exposure. Two different exposure levels were specified for the insulation samples. To accomplish this, the samples were encapsulated in two separate aluminum capsules; the capsules positioned at the ATR core mid-plane and at the top of the fueled region to take advantage of the axial cosine distribution of the neutron and gamma flux; and by varying the length of irradiation time of the two capsules. Disassembly of the irradiated capsules and testing of the insulation samples were performed at the Test Reactor Area (TRA) Hot Cell Facilities. Testing of the samples included shear compression static, shear compression fatigue, flexure static, and electrical resistance measurements

  9. Stereophotogrammetric study of surface topography in ion irradiated silver

    International Nuclear Information System (INIS)

    Sokolov, V.N.; Fayazov, I.M.

    1993-01-01

    The irradiated surface topography of polycrystalline silver was studied using the stereophotogrammetric method. The surface of silver was irradiated with 30 keV argon ions at variation for the ion incidence angle in interval of 0-80 deg relative to a surface normal. The influence of the inclination angle of the sample in the SEM on the cone shape of a SEM-picture of the irradiated surface is discussed. The parameters of cones on the irradiated surface of silver were measured by the SEM-stereomethod. The measurements of the sample section perpendicular to the incidence plane are also carried out

  10. Electrochemical methods for identification of irradiated liquid foods

    International Nuclear Information System (INIS)

    Xie Zongchuan; Ma Li; Shi Shuangping

    1988-01-01

    Samples of 14 kinds of wine, soy, vinegar, spirits, fruits in syrup, etc.were exposed to a Co-60 source. They responded with changes in electric potential and conductance. Especially, the electric potential in irradiated Shugan white spirits (made of sweet potato) was five times that in non-irradiated ones. Eighty five days after irradiation, the electric potential in the irradiated spirits dropped, but was still three times that in non- irradiated ones. The conductance in irradiated spirits was twenty percent more than that in non-irradiated ones. With addition of 0.1% H 2 O 2 to the spirits be- fore irradiation, the electric potential changed even larger

  11. Studies of electron-beam irradiation on ethylene-styrene interpolymers

    CERN Document Server

    Liu, I C

    2002-01-01

    Electron-beam irradiation-induced structural and properties changes on ethylene-styrene interpolymers (ESI) have been studied at electron doses ranging from 0 to 200 kGy. The amounts of species generated by irradiation such as hydroxyls, hydroperoxides, carbonyls and unsaturated double bonds have been analyzed using ATR-FTIR. While the structural changes are minimal for ESI69 comprising 69 wt.% styrene regardless of the dose level, the changes for ESI40 comprising 40 wt.% styrene are dose dependent and reaches a maximum at a dose of 100 kGy. Gel permeation chromatography analysis indicates that macromolecular chain scission occurs at low irradiation dose and crosslinking dominates at high irradiation doses. The average molecular weights between crosslinks, M sub C 's, have been calculated using the Flory-Rehner equation based on data collected from solvent extraction experiments. The M sub C 's of ESI40 samples are much smaller than those of ESI69 samples. Irradiated ESI samples have higher glass transition t...

  12. Stability of vitamin A in irradiated beef liver

    International Nuclear Information System (INIS)

    Taipina, Magda S.; Mastro, Nelida L. del; Lamardo, Leda C.A.

    1997-01-01

    In this study, vitamin A and β-carorene were analized in 3KGy Co-60 γ-irradiation and unirradiated samples of bovine liver. Six different lots of samples were obtained at meat market, two samples per lot weighing about 100g each, keot at -15 0 C as long as possible. Pre-treatment and analysis methopds were those described in Institute Adolfo Lutz Norms for Food Analysis, using two-gram samples in described in Institute Adolfo Lutz Norms for Food Analysis, using two-gram samples in duplicates. The total viramin A content of the samples varied a lot. The means and standard deviations of vitamin A retention percentage after irradiation were 106±8.2 (12 replications). Similarly, β-carotene retention percentage was 98±2.4 (24 replications). The results show that there were no losses of neither vitamin A nor protovitamin A as consequence of irradiation with a dose suitable for the reduction of spoilage and pathogenic organisms. (author). 8 refs., 2 tabs

  13. Effects of gamma irradiation on microbial load and quality characteristics of veal

    Directory of Open Access Journals (Sweden)

    Ebrahim Rahimi

    2013-01-01

    Full Text Available Background: Veal is a rich nutrient medium that provides a suitable environment for proliferation of veal spoiling microorganisms and common food-borne pathogens. In this study, the effects of irradiation on the veal microbiological quality and half life of minced beef during chilled storage was investigated. Materials and Methods: Twenty samples of minced veal were irradiated with doses of 2, 5, 7, and 10 kGy (Cobalt-60, gamma cell 220 and evaluated for their microbiological quality up to 10 days. Results: The results showed that gamma irradiation reduced the number of microorganisms in all the irradiated minced veal samples, with 2, 5, 7, and 10 kGy (P < 0.01. Moreover, the half life of the samples were increased considerably (P < 0.01. In addition, the results indicated that there was a significant difference in the number of coliformes between untreated and irradiated samples (P < 0.05. While, Staphylococcus aureus could not be detected in the irradiated samples with doses of 7 and 10 kGy. Conclusion: These results indicated that irradiation could be employed as an effective mean to inactivate common food-borne pathogens namely S. aureus and increases the half life of veal.

  14. Gamma irradiation effects on tofu sold at the market in South of Jakarta region

    International Nuclear Information System (INIS)

    Idrus Kadir and Harsojo

    2009-01-01

    Tofu is one of Indonesian traditional food which is popular, well consumed and nutritious. Recent reports pointed out that some distributed tofu had low hygienic quality and contained formaline. Therefore, examination for the formaline content and hygienic quality of tofu sold either at supermarket or traditional market is needed. The purposive sampling method has been used. Samples were taken from locations determined previously. Qualitative test to observe the content of formaline and bacteria were conducted on. Tofu obtained from supermarket and traditional markets at South Jakarta which were irradiated with the dose of 3 kGy. The results showed that all of non-irradiated tofu samples observed content formaline. The total amount of aerobic bacteria in non-irradiated tofu sample were found in the range of 2.2 x 10 5 and 1.4 x 10 7 cfu/g, while for irradiated samples were in the range of 2.5 x 10 2 and 2.0 x 10 4 cfu/g. Coli form bacteria in non-irradiated tofu were in the range of 0 and 7.0 x 10 5 cfu/g, while for irradiated tofu were in the range of 2.5 x 10 2 and 2.2 x 10 3 cfu/g. Total amount of Staphylococcus for non-irradiated tofu samples were found in the range of 0 and 1.3 x 10 6 cfu/g, while for irradiated samples were in the range of 0 and 1.5 x 10 2 cfu/g. None of Salmonella was detected in all tofu samples. The pH of non-irradiated and irradiated tofu was in the range of 5.33 and 5.93, while the water content were in the range of 75.11% and 76.99%. The protein contents of non-irradiated and irradiated tofu were in the range of 7.93% and 8.83% respectively. (author)

  15. 无铅、砷金红粉彩颜料的呈色机理%Colouration Mechanism of Lead and Arsenic Free Gold Ruby Famille-Rose Pigments

    Institute of Scientific and Technical Information of China (English)

    曹春娥; 卢希龙; 陈云霞; 沈华荣; 洪琛; 余峰

    2011-01-01

    The phase composition and micro-morphology of lead and arsenic free gold ruby famille-rose pigments before and after decoration firing were investigated by X-ray diffractometer,transmission electron microscope,and energy dispersive X-ray spectro-scope.The colorimetric and spectral analysis of the as-prepared samples was carried out using spectrophotometer to investigate the colouration mechanism of the pigments.The effect of the schedule of decoration firing on size of the colloidal gold particles was ana-lyzed.The results indicate that a large amount of colloidal gold particles with size of 20–30 nm are well dispersed in the glassy phase,appearing a ruby color,which is due to the strong absorption of green light of about 520 nm wavelength caused by the localized sur-face plasmon resonance of colloidal gold particles under visible light radiation.There was no clear dissolution and/or new phase forming reaction between Purple of Cassius and frit after decoration firing.The decoration firing schedule had little effect on the size of colloidal gold particles%采用X射线衍射、透射电子显微镜和能谱仪等研究了无铅、砷金红粉彩颜料彩烤前后的物相组成与显微形貌,用分光测色仪对样品进行色度及光谱分析,研究了其呈色机理,并探讨了彩烤制度对金胶粒子大小的影响。结果表明:无铅、砷金红颜料彩烤后呈红紫色是由于在光波作用下,金胶粒子产生局域表面等离子体共振,强烈吸收波长520 nm左右的绿色光所致。颜料彩烤后,大量粒径在20~30 nm的金胶粒子均匀分散于玻璃相中,色剂紫金泥与熔剂之间没有产生明显的溶解和生成新相,彩烤制度对金胶粒子大小影响不明显

  16. Evaluation of the physicochemical stability of liquid soy lecithin after decontamination by gamma irradiation

    International Nuclear Information System (INIS)

    Adeil Pietranera, Maria S.; Narvaiz, Patricia

    1999-01-01

    Commercial samples of liquid soy lecithin were irradiated with different gamma doses up to 5 kGy. Several physicochemical properties were determined every 2 months for a period of 8 months after the irradiation and were compared to those of blank samples. No significant differences were found between the physicochemical properties of irradiated and non-irradiated soy lecithin samples. (author)

  17. Storage properties of irradiated potatoes and onions. Part of a coordinated programme on the Asian Regional Cooperative Project on Food Irradiation

    International Nuclear Information System (INIS)

    Hayashi, T.

    1984-12-01

    Quality changes with regard to browning of inner buds and sprouting of irradiated onions variety Kitamiki and Ohotsuku were investigated. One ton of each variety was irradiated with either 38.1 or 65.2 Gy at the Commercial Potato Irradiator in Shihoro and stored either at 0 deg. C or 5 deg. C. After 6 months of storage, they were taken out to be stored at room temperature. It was observed that green inner buds developed in most unirradiated onions which showed no external sprouting irrespective of storage temperature. Irradiated onions show no external or internal sprouting but exhibited browning of small inner buds. Unirradiated onions rooted slightly during storage at low temperature. None of the irradiated samples showed rooting. Neither of the samples spoiled significantly during storage. It was concluded that storage at room temperature accelerated sprouting and development of green inner buds of unirradiated onions and browning of small inner buds in irradiated ones. During off-seasons, only irradiated onions stored at low temperatures have qualities of commercial significance

  18. Evaluation of sensory attributes and some-quality indices of irradiated spices

    International Nuclear Information System (INIS)

    Subbulakshmi, G.; Udipi, Shobha; Raheja, Reshma; Sharma, Arun; Padwal Desai, S.R.; Nair, P.M.

    1991-01-01

    Ground pepper, chilli, coriander, cumin, turmeric and a spice mix (sambar powder) exposed to an absorbed dose of 10 kGy of gamma irradiation were studied for microbial and sensory quality changes, if any, on storage for 3 months. No significant differences between the irradiated and non-irradiated samples could be observed in their sensory qualities. While no increase in microbial load in sealed irradiated samples could be observed, those that were irradiated but opened repeatedly for daily use did show a marginal increase in microbial load. (author). 8 refs., 1 tab

  19. Dose determination in irradiated chicken meat by ESR method

    International Nuclear Information System (INIS)

    Polat, M.

    1996-01-01

    In this work, the properties of the radicals produced in chicken bones have been investigated by ESR technique to determine the amount of dose applied to the chicken meats during the food irradiation. For this goal, the drumsticks from 6-8 weeks old chickens purchased from a local market were irradiated at dose levels of 0; 2; 4; 6; 8 and 10 kGy. Then, the ESR spectra of the powder samples prepared from the bones of the drumsticks have been investigated. Unirradiated chicken bones have been observed to show a weak ESR signal of single line character. CO-2 ionic radicals of axial symmetry with g=1.9973 and g=2.0025 were observed to be produced in irradiated samples which would give rise to a three peaks ESR spectrum. In addition, the signal intensities of the samples were found to depend linearly on the irradiation dose in the dose range of 0-10 kGy. The powder samples prepared from chicken leg bones cleaned from their meats and marrow and irradiated at dose levels of 1, 2, 3, 4, 5, 6, B, 10, 12,14, 16, 1B, 20 and 22 kGy were used to get the dose-response curve. It was found that this curve has biphasic character and that the dose yield was higher in the 12-1B kGy dose range and a decrease appears in this curve over 18 kGy. The radical produced in the bones were found to be the same whether the irradiation was performed after stripping the meat and removing the marrow from the bone or before the stripping. The ESR spectra of both irradiated and non irradiated samples were investigated in the temperature range of 100 K-450 K and changes in the ESR spectra of CO-2 radical have been studied. For non irradiated samples (controls). the signal intensities were found to decrease when the temperature was increased. The same investigation has been carried out for irradiated samples and it was concluded that the signal intensities relative to the peaks of the radical spectrum increase in the temperature range of 100 K-330 K, then they decrease over 330 K. The change in the

  20. utilization of some physical methods for detection of some irradiated foods

    International Nuclear Information System (INIS)

    Mohammed, I.A.S

    2007-01-01

    the present investigation was carried out to establish a detection method for irradiated black pepper and marjoram using thermoluminescence (TL) and wheat, cinnamon and ginger using viscosity measurement. all samples were packed in polyethylene bags then irradiated at 5,10 and 15 kGy for black pepper, marjoram, cinnamon and ginger. wheat was irradiated at 1,2 and 3 kGy. all samples were stored for eight months at room temperature. results indicated that irradiation treatment caused markedly increasing in TL intensity for irradiated black pepper and marjoram while irradiation treatment decreased apparent viscosity of wheat flour, cinnamon and ginger powder, post irradiation and during storage. therefore, it could be concluded that the TL analysis can be used to detect irradiated black pepper and marjoram, also viscosity measurement can be used to detect irradiate wheat flour, cinnamon and ginger powder than non-irradiated ones after irradiation process and also during 8 months of storage at ambient temperature

  1. Comet assay in the detection of irradiated garlic; Teste do cometa na deteccao de alho irradiado

    Energy Technology Data Exchange (ETDEWEB)

    Villavicencio, Anna Lucia C.H.; Marin-Huachaca, Nelida Simona; Romanelli, Maria Fernanda [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: villavic@net.ipen.br; Delincee, Henry [Federal Research Centre for Nutrition - BFE, Karlsruhe (Germany)]. E-mail: henry.delincee@bfe.uni-karlsruhe.de

    2002-07-01

    The increased claim for fresh produce has forced a consensus between nations to pay more attention to the phytosanitary regulations. Inhibition of sprouting of bulbs and tubers by applying ionising radiation is authorised by the National Food Codes in Brazil. The availability of methods for detection of irradiated food will contribute to increase consumers' confidence. A quick and simple screening test to indicate whether a food product has been irradiated or not was utilised in this study. The DNA comet assay was applied to verify whether garlic imported from China had been irradiated or not. This test has already been adopted as a European Standard (EN 13784), for detection of irradiated food. Non-irradiated control samples of garlic and garlic treated with maleic hydrazide were compared with garlic samples irradiated in our department. The unirradiated samples exhibited only limited DNA migration. If samples were irradiated, an increased DNA fragmentation was observed which permitted the discrimination between non-irradiated and irradiated samples. Since the garlic samples from China showed only very limited DNA fragmentation, they were deemed non-irradiated. Thus, this simple screening test was shown to be successful for identification of an irradiation treatment. (author)

  2. Irradiation of ground beef with the purpose of refrigerated storage

    International Nuclear Information System (INIS)

    Keskin, S.

    1977-01-01

    Ground beef packaged in polyethylene film was irradiated at different dose levels ranging from 0.25 to 1.0 Mrad and stored at 3+-1 0 C. Bacteriological and organoleptic evaluations were carried out immediately after irradiation and at weekly intervals thereafter. The red color of the meat was darker after irradiation and this darkening increased with radiation dose. This color change was limited to the surface of the samples. The results of the bacteriological and organoleptic examination indicate that irradiation at 0.25 Mrad permits refrigerated storage of ground beef for 3 weeks, 0,5 Mrad for 6 weeks. Coliforms were found only in non-irradiated samples [fr

  3. Damage studies on tungsten due to helium ion irradiation

    International Nuclear Information System (INIS)

    Dutta, N.J.; Buzarbaruah, N.; Mohanty, S.R.

    2014-01-01

    Highlights: • Used plasma focus helium ion source to study radiation induced damage on tungsten. • Surface analyses confirm formation of micro-crack, bubbles, blisters, pinholes, etc. • XRD patterns confirm development of compressive stress due to thermal load. • Reduction in hardness value is observed in the case of exposed sample. - Abstract: Energetic and high fluence helium ions emitted in a plasma focus device have been used successfully to study the radiation induced damage on tungsten. The reference and irradiated samples were characterized by optical microscopy, field emission scanning electron microscopy, X-ray diffraction and by hardness testers. The micrographs of the irradiated samples at lower magnification show uniform mesh of cracks of micrometer width. However at higher magnification, various types of crystalline defects such as voids, pinholes, bubbles, blisters and microcracks are distinctly noticed. The prominent peaks in X-ray diffraction spectrum of irradiated samples are seen shifted toward higher Bragg angles, thus indicating accumulation of compressive stress due to the heat load delivered by helium ions. A marginal reduction in hardness of the irradiated sample is also noticed

  4. Development of a microbiological irradiation detection method for spices

    International Nuclear Information System (INIS)

    Koshikawa, T.; Takekawa, T.; Miyahara, M.

    2009-01-01

    In order to judge whether certain spices had been irradiated or not, we examined the possibility of developing a method based on the microbiological examination of spices. We used the total bacteria count in conjunction with the ratio of B. megaterium and B. cereus to the total bacteria count. The examination results of 6 kinds of spices with or without irradiation (black pepper, white pepper, coriander, paprika, ginger and turmeric), were as follows. Total bacteria counts over 10E5 CFU/g indicated that the samples were 'unirradiated'. When the total bacteria count was less than 10E5 CFU/g, and the ratio of B. megaterium and B. cereus to the total count was more than 30%, a history of irradiation of the samples was indicated. When ratios of B. megaterium and B. cereus were less than 30% and the total bacteria count was also less than 10E5 CFU/g, 'uncertainty' of irradiation was indicated. In this case, it would be possible to confirm whether spices were 'unirradiated' or 'irradiated' by using another detection method. This detection method was applicable to other spices except for paprika. The samples judged as 'irradiated' by using this detection method, surely proved to have a history of irradiation treatment

  5. Study on biologically active substances in irradiated apple juice

    International Nuclear Information System (INIS)

    Tencheva, S.

    1975-01-01

    The radiochemical changes proceeding by irradiation of foodstuffs rich in carbohydrates are studied. For the purpose pure solutions of D-glucose, D-fructose and sucrose and fresh apple juice, irradiated with 0,5 and 1,0 Mrad are investigated. Changes set in UV-spectra of the irradiated foodstuffs, the specific reaction of malonic dialdehyde formation with 2-thiobarbituric acid and the formation of carbonyl compounds reacting with 2,4-dinitro phenylhydrazine are studied. Results show that in the irradiated sample solutions of sugars and apple juice two peaks are formed. The malonic dialdehyde formation depends on the dose of irradiation applied. The newly formed carbonyl compounds both in the sample solutions and in the juice are 8 to 9 in number. (author)

  6. Irradiation detection of coffee mate by electron spin resonance (ESR)

    Energy Technology Data Exchange (ETDEWEB)

    Ozsayin, Fulya [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey); Polat, Mustafa, E-mail: polat@hacettepe.edu.t [Physics Engineering Department, Hacettepe University, 06800 Ankara (Turkey)

    2011-06-15

    Un-irradiated coffee mate samples do not exhibit any ESR signal. However, the samples exposed to UV and gamma radiation exhibit an ESR singlet and a large unresolved ESR signal, respectively. The dose-response curves of the samples exposed to UV and gamma radiations were found to be described well by an exponential and linear functions, respectively. Variable temperature and fading studies at room temperature showed that the radiation-induced radicals in coffee mate sample are very sensitive to temperature. The discrimination between un-irradiated and irradiated coffee mate samples can be done just comparing their ESR spectra. However, determination of the radiation dose received by the sample cannot be possible because of the fast decay of signal intensity at room temperature.

  7. Interaction of hydrogen and its isotopes with irradiated beryllium

    International Nuclear Information System (INIS)

    Tazhibaeva, I.L.; Shestakov, V.P.; Klepikov, A.Kh.; Pomanenko, O.G.; Chikhraj, E.V.; Kenzhin, E.A.; Zverev, V.V.; Kolbanenkov, A.N.

    2000-01-01

    In the article the results of experiments on hydrogen and its isotopes accumulation and gas-release from irradiated beryllium are presented. The irradiation was conducted at different media and temperatures in the RA and IVG.1M reactors. The measurements were carried out by thermal desorption method. Hydrogen release from beryllium samples saturated at different conditions were calculated. Dependence of hydrogen confinement character in beryllium from grain orientation in the sample, temperature and irradiation rate was revealed

  8. Annealing effects on resistivity and Hall coefficient of neutron irradiated silicon

    International Nuclear Information System (INIS)

    Biggeri, U.

    1995-01-01

    High Temperature Annealing (HTA) treatment has been carried out on fast-neutron irradiated silicon samples with temperatures up to 300 C. Fluences of irradiation up to 1x10 14 n/cm 2 were used. Before annealing, samples irradiated with fluences higher than 1x10 13 n/cm 2 suffered the type conductivity inversion from n-type to p-type. The changes in the resisitivity and Hall coefficient during each annealing step have been measured by Hall effect analysis. Results indicate the possible creation of acceptors for low temperature annealing up to 150 C and the phosphorous release by E centres at annealing temperatures among 150 C and 200 C. Heating samples up to 300 C allows the recovering of the sample resistivity to its value before irradiation, with the peculiarity that bulks inverted to p-type after irradiation does not come back to n-type after annealing. (orig.)

  9. Improving the microbial safety and quality of quail carcasses by gamma irradiation

    International Nuclear Information System (INIS)

    Rady, A.H.; Khalaf, H.H.; Afifi, E.A.; Nasr, E.H.

    2002-01-01

    This investigation aims to study the possibility of using gamma irradiation for improving the microbial safety quality of quail carcasses. One hundred quail carcasses were examined for the presence of salmonella. The examination illustrated that 70 carcasses from all examined carcasses were positive for salmonella. therefore, the contaminated quail carcasses were gamma irradiated at 2, 4 and 6 kGy doses and the effects of these treatments on the microbiological aspects and chemical properties of samples under investigation were evaluated. The results indicated that, the chemical composition of samples did not alter by gamma irradiation treatment. Furthermore, irradiation of samples at doses of 2, 4 and kGy greatly reduced its microbial count. Moreover, irradiation doses of 2 and 4 kGy completely destroyed salmonella and enterococcus faecalis, respectively. In addition, the acid value, peroxide value and thiobarbituric acid value were increased after irradiation. On the other hand, irradiation treatment had no real effects on the total volatile basic nitrogen content and amino acid composition of samples under investigation

  10. Sprout inhibition of onions by irradiation

    International Nuclear Information System (INIS)

    Siddiqui, A.K.; Hossain, M.A.; Choudhury, M.S.U.; Matin, M.A.; Amin, M.R.; Hossain, M.M.

    1979-01-01

    Onions of a set grown local variety were gamma irradiated in the dose range of 2-8 Krad. The irradiated onions were then stored in 10 lb. bags and in single layer at an average ambient temperature of 83 0 F and 79% relative humidity. Radiation doses of 4 Krad and above were completely inhibitory to sprouting of onions. Weight loss and rot incidence were markedly reduced in irradiated samples up to 10 months in both jute bag and single layer storage. An analysis of the cost benefit revealed that commercial irradiation of onions is economically feasible in Bangladesh if post-irradiation of storage extends for a period of over 6 months. (author)

  11. Defect formation in oxygen- and boron- implanted MOS structures after gamma irradiation

    CERN Document Server

    Kaschieva, S; Skorupa, W

    2003-01-01

    The effect of gamma irradiation on the interface states of ion-implanted MOS structures is studied by means of the thermally stimulated charge method. 10-keV oxygen- or boron- (O sup + or B sup +) implanted samples are gamma-irradiated with sup 6 sup 0 Co. Gamma irradiation creates electron levels at the SiSiO sub 2 interface of the samples in a different way depending on the type of the previously implanted atoms (O sup + or B sup +). The results demonstrate that the concentration of the shallower levels (in the silicon band gap) of oxygen-implanted samples increases more effectively after gamma irradiation. The same irradiation conditions increase more intensively the concentration of the deeper levels (in the silicon band gap) of boron-implanted samples. (orig.)

  12. Preservation of squid rings by gamma irradiation. Microbiological, sensory and physicochemical aspects

    International Nuclear Information System (INIS)

    Tomac, A.; Yeannes, M.I.; Cova, M.C.; Narvaiz, Patricia

    2011-01-01

    The aim of this work was to analyze the use of gamma irradiation to preserve squid rings during refrigerated storage. Skinned rings of 'Illex argentinus' were packed in polyethylene/polyamide bags and gamma irradiated at 0, 2, 3 and 4 kGy with a cobalt-60 source at a semi-industrial irradiation facility. Samples were kept at 4 ± 1 °C during transportation, irradiation and 21 storage days. Mesophilic and psychrotrophic aerobic bacteria, Staphylococcus aureus, enterobacteriaceae, total coliforms, Escherichia coli, and sulphite-reducing clostridia were analyzed, as well as p H, total volatile basic nitrogen, color, and sensory parameters like aspect, color, odor, taste, texture and overall acceptability. Irradiation initially reduced three and two log cycles, respectively, of mesophilic and psychrotrophic bacterial counts, trend which was maintained during storage. Enterobacteriaceae and coliform growths were also controlled by this treatment. S. aureus, E. coli and sulphite-reducing clostridia were not detected in any sample. p H and TVBN values increased during storage time, being significantly lower in irradiated samples. Irradiation slowed down color changes during storage, measured as a* and b*. Color difference (DE2000) was significantly higher in control samples as compared to irradiated rings since the 6 th day. Sensory acceptability was not affected by gamma irradiation at any of the applied doses, being shelf-life extended at least 14 days in 3 kGy samples. (author) [es

  13. Application of gamma irradiation for the microbiological safety of sliced cheddar cheese

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Joo; Song, Beom Seok; Kim, Jae Hun; Choi, Jong Ill; Lee, Ju Woon; Byun, Myung Woo [Radiation Research Center for Innovative Technology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Jo, Cheo Run [Dept. of Animal Science and Biotechnology, Chungnam National University, Daejeon (Korea, Republic of)

    2007-05-15

    This study was conducted to establish the microbiological safety of sliced cheddar cheese with gamma irradiation. Total aerobic bacteria was 2.50 Log CFUg-1 in non-irradiated sample. No viable cells were observed in the gamma-irradiated at 1 kGy and over. D10 value for Listeria monocytogenes and Staphylococcus aureus inoculated in sliced cheddar cheese were 0.64 and 0.54 kGy, respectively. TBARS (2-thiobarbituric acid reactive substances) values were increased as irradiation dose was increased, but there was no significant difference between nonirradiated and irradiated samples at 1 kGy. Sensory evaluation showed there was no significant difference between samples irradiated at 1 kGy and non-irradiated in respect of color, odor, overall acceptability. Theses results indicated that gamma irradiation at 1 kGy was considered to be an effective treatment to ensure the microbiological safety of sliced cheddar cheese with minimal change of sensory, even though further studies should be investigated to reduce the deterioration of sensory quality induced by gamma irradiation.

  14. Physicochemical Properties of Gamma-Irradiated Corn Starch

    International Nuclear Information System (INIS)

    Lee, Y.J.; Lim, S.T.; Kim, S.Y.; Han, S.M.; Kim, H.M.; Kang, I.J.

    2006-01-01

    Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples

  15. Utilization of irradiation on food preservation

    International Nuclear Information System (INIS)

    Cho, Han Ok; Kwon, Joong Ho; Byun, Myung Woo; Kim, Suck Won; Yang, Jae Seung

    1986-12-01

    Dried marine products showed some higher microbial contaminations than dried agricultural products and the load of microorganisms was different depending on the kind of samples. In comparative effects of radiation and ethylene oxide (E.O) fumigation, total aerobic and acid tolerant bacteria were reduced by 2 to 3 log orders by gamma irradiation at 3 to 5 KGy. The sterilizing doses for coliforms, fungi and total bacterial count were shown to be 5 KGy, 5 to 7 KGy, and 7 tp 10 KGy, respectively. D values of total bacterial count in dried agricultural and marine products ranged from 0.80 to 3.99 KGy. In the meantime, E.O. treatment proved insufficient to reduce the microbial load of highly contaminated samples below the 10 per gram of the international hygienic standard, especially in total aerobic bacteria, thermophiles and gun fungi. An optimum dose of irradiation had little detrimental effect on the chemical components of the sample, but E.O. treatment brought about a significant reduction especially in amino acid and ascorbic acid contents. The values of thiobarbituric acid(TBA), PH and trimethyleamine(TMA), as quality parameters, were more stable during the storage period in the irradiated groups than the control and E.O. treatment caused changes in color, leading to deterioration of overall appearance of the samples. Sensory evaluation after three months of storage at room temperatures indicated that the irradiated samples with doses of 5 to 10 KGy were more acceptable in the overall flavor and appearance of each product than the nontreated control group as well as the E.O. fumigated samples

  16. Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

    Science.gov (United States)

    To, C. K.; Yang, B.; Beling, C. D.; Fung, S.; Ling, C. C.; Gong, M.

    2011-01-01

    Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2MeV electrons with fluence of 6x1017cm-2. Isochronal annealing from 100°C-800°C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300°C and 600 °C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300°C and 600°C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300°C and 700°C.

  17. Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

    Energy Technology Data Exchange (ETDEWEB)

    To, C K; Yang, B; Beling, C D; Fung, S; Ling, C C [Department of Physics, University of Hong Kong (Hong Kong); Gong, M, E-mail: sfung@hkucc.hku.h, E-mail: edwardto04@yahoo.com.h [Department of Physics, Sichuan University, Chengdu (China)

    2011-01-01

    Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2 MeV electrons with fluence of 6x10{sup 17}cm{sup -2}. Isochronal annealing from 100 deg. C - 800 deg. C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300 deg. C and 600 deg. C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300 deg. C and 600 deg. C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300 deg. C and 700 deg. C.

  18. Positron annihilation study of defects in electron-irradiated single crystal zinc oxide

    International Nuclear Information System (INIS)

    To, C K; Yang, B; Beling, C D; Fung, S; Ling, C C; Gong, M

    2011-01-01

    Pressurized melt grown zinc oxide (ZnO) single crystals purchased from Cermet Inc. were irradiated by 2 MeV electrons with fluence of 6x10 17 cm -2 . Isochronal annealing from 100 deg. C - 800 deg. C was performed on the crystals under argon and air ambience. Variable Energy Doppler Broadening Spectroscopy (VEDBS) was carried out on both the as-grown and the irradiated samples at each annealing step. The migration, agglomeration and annealing of grown-in and irradiated-introduced defects were studied. It was observed that the grown-in vacancy-type defects concentration decreased at 300 deg. C and 600 deg. C. For the irradiated sample annealed in argon, the positron trapping vacancy-type defect concentration decreased at 300 deg. C and 600 deg. C. Further annealing the as-grown and irradiated samples in argon increased the S parameter further. For the irradiated sample annealed in air, the vacancy-type defect concentration decreases at 300 deg. C and 700 deg. C.

  19. Microbiological possibilities to demonstrate that strawberries have been irradiated

    International Nuclear Information System (INIS)

    Tamminga, S.K.; Beumer, R.R.; Kampelmacher, E.H.

    1975-01-01

    Samples of greenhouse and outdoor-grown strawberries were divided into two portions, they were wrapped and one portion was irradiated at 200 krad. The composition of the microflora before and after irradiation was investigated. The flora of the non-irradiated samples was composed mainly of gram-negative rod-shaped bacteria belonging, with only a few exceptions, either to the Enterobacteriaceae-family or to the genus Pseudomonas. Also, moulds and yeasts were frequently encountered in varying quantities. Moulds and yeasts did not appear to make good indicator organisms. Gram-negative rod-shaped bacteria were always found to be absent after irradiation when solid media were used, even when starting from samples with numbers in the order of magnitude 10 5 -10 6 /gm. When outdoor-grown strawberries were used, this always led to a clear difference from the cooresponding untreated samples. Greenhouse strawberries, however, sometimes contain, even if they have not been treated, only a very small number of micro-organisms. Consequently, if gram-negative rod-shaped bacteria are present on strawberries they most probably have not been irradiated. Of course, this does not apply if post-contamination has been possible. If there is no growth of the above mentioned bacteria on any of te media used, considerable possibility exists that irradiation has taken place. (orig./MG) [de

  20. Irradiation effects on transport properties of polyaniline and polyaniline/bentonite composite

    Energy Technology Data Exchange (ETDEWEB)

    Tilki, T., E-mail: tahirtilki@sdu.edu.tr [Suleyman Demirel University, Faculty of Arts and Sciences, Department of Chemistry, 32260 Isparta (Turkey); Karabulut, O. [Pamukkale University, Faculty of Arts and Sciences, Department of Physics, Denizli (Turkey); Yavuz, M. [Suleyman Demirel University, Faculty of Arts and Sciences, Department of Chemistry, 32260 Isparta (Turkey); Kaplan, A. [Suleyman Demirel University, Faculty of Arts and Sciences, Department of Physics, Isparta (Turkey); Cabuk, M. [Suleyman Demirel University, Faculty of Arts and Sciences, Department of Chemistry, 32260 Isparta (Turkey); Mus Alparslan University, Faculty of Arts and Sciences, Department of Chemistry, Mus (Turkey); Takanoglu, D. [Pamukkale University, Faculty of Arts and Sciences, Department of Physics, Denizli (Turkey)

    2012-08-15

    In this study, the effects of irradiation on pure polyaniline and polyaniline/bentonite composites synthesized chemically were investigated by means of thermogravimetric measurements, UV, SEM, XRD, absorption and temperature dependent electrical conductivity in the temperature range of 85-400 K. The irradiation process was carried out in air in a conventional gamma chamber, which uses a {sup 60}Co source and the samples were exposed to dose 40 kGy. The initial decomposition and first degradation temperatures of PAni/Bnt and Irradiated PAni/Bnt composites obtained from thermogravimetric measurements were higher than those of PAni and irradiated PAni. This could have been caused by the treatment with bentonite during aniline polymerization. The XRD patterns revealed that the peak positions of the as-prepared and irradiated samples were the same but the intensities of the peaks decreased with irradiation due to breaking of the polymer chain, which induces more amorphous regions in the polymer structure. It was found from temperature dependent conductivity measurements that the radiation significantly influenced the conductivity of PAni and PAni/Bnt composites. The conductivity results show that the dominant conduction mechanisms were hopping for all samples due to wide range of localized states present near the Fermi level. -- Highlights: Black-Right-Pointing-Pointer The effects of irradiation on PAni and PAni/Bnt composites were investigated. Black-Right-Pointing-Pointer We observed that irradiation increases the homogeneity of the samples. Black-Right-Pointing-Pointer The band edge is shifted toward lower photon energies in the irradiated samples. Black-Right-Pointing-Pointer The conductivity of PAni and PAni/Bnt composites were changed by the irradiation. Black-Right-Pointing-Pointer The dominant conduction mechanism was found to be Mott's variable range hopping.

  1. Irradiation effects in superconductor oxides. Effets d'irradiation dans les oxydes supraconducteurs

    Energy Technology Data Exchange (ETDEWEB)

    Rullier-Albenque, F; Konczykowski, M [CEA-Ecole Polytechnique, 91 - Palaiseau (France). Lab. d' Etudes des Solides Irradies

    1993-01-01

    Several effects of irradiation on the 92 K - oxide superconductor YBa[sub 2]Cu[sub 3]O[sub 7] are reported. Whatever irradiation type, the critical temperature T[sub c] is found to decrease and the resistivity to increase. At sufficiently high damage levels, YBa[sub 2]Cu[sub 3]O[sub 7] is no longer superconducting and even displays a semiconducting-like behaviour. The alterations of superconducting properties are clearly related to oxygen defects - in the CuO[sub 2] planes or CuO chains... but we have shown experimentally that copper defects are also important. Magnetic properties of YBa[sub 2]Cu[sub 3]O[sub 7] in mixed state are also very sensitive to irradiation. By pinning the flux lines, irradiation defects can considerably increase the critical current density j[sub c]. At present, irradiations by highly energetic heavy ions (6 GeV Pb for instance), which produce cylindrical tubes of amorphous material (latent tracks) throughout the whole thickness of the samples, are probably the most efficient way to enhance j[sub c]. (Author). 18 refs., 7 figs.

  2. Physico-chemical changes in heavy ions irradiated polymer foils by differential scanning calorimetry

    International Nuclear Information System (INIS)

    Ciesla, K.; Trautmann, Ch.; Vansant, E.F.

    1994-01-01

    The sample of commercial PETP (Hostaphan) and very heavy ions irradiated products were investigated by differential scanning calorimetry in nitrogen flow. Irradiation were performed with Dy ions of 13 MeV/u with fluences 5 x 10 10 ions/cm 2 . Differences were observed in melting behaviour of unirradiated and irradiated foils. The influence of irradiation conditions on the results was noticed. Moreover the samples of polyimide (Kapton) and polycarbonate (Macrofol) irradiated in similar conditions were examined by DSC. The DSC traces have been compared with those of unirradiated reference samples. (author). 8 refs, 5 figs

  3. Antioxidative activity of carnosine in gamma irradiated ground beef and beef patties

    International Nuclear Information System (INIS)

    Badr, H.M.

    2005-01-01

    The activity of carnosine as a natural antioxidant in gamma irradiated ground beef and beef patties was studied. Samples of ground beef, in absence and presence of 0.5% or 1.0% carnosine, as well as raw and cooked beef patties prepared with 1.5% salt (NaCl), in absence and presence of 0.5% or 1.0% carnosine, were gamma irradiated at doses of 2 and 4 KGy. Then, the extent of oxidation in irradiated and non-irradiated samples of ground beef and raw beef patties was determined during refrigerated (4± 1 degree C) and frozen (-18 degree C) storage, while was determined for cooked beef patties during refrigerated storage only. Moreover, the determination of metmyoglobin (MetMb) accumulation and sensory evaluation for the visual colour were carried out for samples of ground beef and raw patties. The results indicated that salt or salt and cooking can accelerate the oxidative processes and significantly increased the peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) in the prepared non-irradiated samples. However, salt slowed down the accumulation of MetMb in raw patties. Irradiation treatments and storage in absence of carnosine significantly increased with higher rates the PV and TBARS in salted or salted and cooked beef samples. Moreover, irradiation and storage significantly increased the formation of MetMb in ground beef and raw patties in absence of carnosine. Addition of carnosine significantly reduced the oxidative processes and MetMb formation (proportionally to the used concentration) in samples post irradiation and during storage. Furthermore, carnosine exerted significant efficacy in maintaining an acceptable visual red colour post irradiation and during storage of ground beef and raw patties. These results demonstrate that carnosine can be successfully used as a natural antioxidant to increase the oxidative stability in gamma irradiated raw and cooked meat products

  4. Identification of irradiated refrigerated pork with the DNA comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, M.M. E-mail: villavic@net.ipen.br; Marin-Huachaca, N.S.; Mancini-Filho, J. E-mail: jmancini@usp.br; Delincee, H.; Villavicencio, A.L.C.H. E-mail: henry.delincee@bfe.uni-karlsruhe.de

    2004-10-01

    Food irradiation can contribute to a safer and more plentiful food supply by inactivating pathogens, eradicating pests and by extending shelf-life. Particularly in the case of pork meat, this process could be a useful way to inactivate harmful parasites such as Trichinella and Taenia solium. Ionizing radiation causes damage to the DNA of the cells (e.g. strand breaks), which can be used to detect irradiated food. Microelectrophoresis of single cells ('Comet Assay') is a simple and rapid test for DNA damage and can be used over a wide dose range and for a variety of products. Refrigerated pork meat was irradiated with a {sup 60}Co source, Gammacell 220 (A.E.C.L.) installed in IPEN (Sao Paulo, Brazil). The doses given were 0, 1.5, 3.0 and 4.5 kGy for refrigerated samples. Immediately after irradiation the samples were returned to the refrigerator (6 deg. C). Samples were kept in the refrigerator after irradiation. Pork meat was analyzed 1, 8 and 10 days after irradiation using the DNA 'Comet Assay'. This method showed to be an inexpensive and rapid technique for qualitative detection of irradiation treatment.

  5. Identification of irradiated refrigerated pork with the DNA comet assay

    Science.gov (United States)

    Araújo, M. M.; Marin-Huachaca, N. S.; Mancini-Filho, J.; Delincée, H.; Villavicencio, A. L. C. H.

    2004-09-01

    Food irradiation can contribute to a safer and more plentiful food supply by inactivating pathogens, eradicating pests and by extending shelf-life. Particularly in the case of pork meat, this process could be a useful way to inactivate harmful parasites such as Trichinella and Taenia solium. Ionizing radiation causes damage to the DNA of the cells (e.g. strand breaks), which can be used to detect irradiated food. Microelectrophoresis of single cells (``Comet Assay'') is a simple and rapid test for DNA damage and can be used over a wide dose range and for a variety of products. Refrigerated pork meat was irradiated with a 60Co source, Gammacell 220 (A.E.C.L.) installed in IPEN (Sa~o Paulo, Brazil). The doses given were 0, 1.5, 3.0 and 4.5kGy for refrigerated samples. Immediately after irradiation the samples were returned to the refrigerator (6°C). Samples were kept in the refrigerator after irradiation. Pork meat was analyzed 1, 8 and 10 days after irradiation using the DNA ``Comet Assay''. This method showed to be an inexpensive and rapid technique for qualitative detection of irradiation treatment.

  6. Qualities of Patin Fishball Irradiated by Gamma Rays (60Co)

    International Nuclear Information System (INIS)

    Yarosita FS; Bustami I; Winarti Z; Rindy PT

    2004-01-01

    An experiment on patin fishball quality using gamma irradiation ( 60 Co) has been conducted. Samples were irradiated at 0, 1, 3 and 5 kGy and stored in refrigerator at temperature 10 o C for sixty days. Samples were analysed every fifteen days, except content of fat and protein that analysed only at the beginning and the end of storage. The purpose of this experiment is to know the quality changes of patin fishball irradiated during storage, by measuring of chemical (content of fat, protein, water, TVB value, pH value) and microbiology (TPC aerobic and anaerobic bacteria) changes. The results showed that irradiation did not affect macro nutrient contents (content of fat, protein and water) of patin fishball during storage but irradiation can affect TVB and pH values. Irradiation at 1 kGy can reduce one logarithmic cycle of total aerobic and anaerobic bacteria. The storage life of irradiated patin fishball treated at 1, 3 and 5 kGy could be extended up to 15, 30 and 60 days, respectively. Control samples the storage life could be extended less than 15 days. (author)

  7. Mechanical behavior of styrene grafted PVC films by electron beam irradiation

    International Nuclear Information System (INIS)

    Cardoso, Jessica R.; Moura, Eduardo; Somessari, Elisabeth S.R.; Silveira, Carlos G.; Paes, Helio A.; Souza, Carlos A.; Manzoli, Jose E.; Geraldo, Aurea B.C.

    2011-01-01

    The polyvinyl chloride (PVC) is a technological and low cost polymer, however it presents high sensitivity to high energy irradiation because of the weakness of carbon-chloride bond face to carbon-carbon and carbon-hydrogen bonds. Grafting is a type of co-polymerization process that can allow it an increase of mechanical characteristics. The aim of this work is to evaluate the mechanical properties of styrene grafted PVC by electron beam irradiation using mutual and pre-irradiation methods to verify the mechanical resistance changes of obtained product whether grafting process is applied from non-irradiated or from pre-irradiated substrates. The irradiation procedures were performed in atmosphere air or inert atmosphere and the irradiation conditions comprised doses from 10 kGy to 100 kGy and dose rates of 2.2 kGy/s and 22.4 kGy/s. The styrene grafted samples were analyzed by gravimetry to determinate the grafting yield; the final values have been averaged from a series of three measurements. The Mid-A TR-FTIR was the spectrophotometer technique used for qualitative/semi-quantitative analysis of grafted samples. The Young's module and tensile strength of pre-irradiated and grafted PVC samples at both methods were measured at a Lloyd LXR tensile tester at a cross-head speed of 10.00 mm/min. We observed the decrease of Young's module and tensile strength with the increase of absorbed dose at pre-irradiated PVC samples. These mechanical parameters results are discussed. (author)

  8. 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 ...

  9. Improvement in the textural qualities of irradiated legumes

    International Nuclear Information System (INIS)

    Nene, S.P.; Vakil, U.K.; Sreenivasan, A.

    1975-01-01

    The potential for use of gamma radiation processing to improve texture, hydration and cooking quality of pulses, particularly red gram, has been examined. The textural changes in irradiated pulses in terms of softening is measured by a texturometer, Radiation (1 Mrad) processing of pulses resulted in reduction of cooking time varying from 8 to 39%, red gram showing the maximum reduction. Initial higher hydration rate on soaking and cooking, stabilized on prolonged cooking and resulted in better and uniform texture of irradiated red gram. In the uncooked, irradiated (1 Mrad) sample, destruction of riboflavin was negligible, whereas thiamine and niacin showed about 7% loss. However, the vitamins were retained better in the samples irradiated and then cooked, compared to the corresponding control ones. (F.J.)

  10. Improvement in the textural qualities of irradiated legumes

    Energy Technology Data Exchange (ETDEWEB)

    Nene, S P; Vakil, U K; Sreenivasan, A [Bhabha Atomic Research Centre, Bombay (India). Biochemistry and Food Technology Div.

    1975-01-01

    The potential for use of gamma radiation processing to improve texture, hydration and cooking quality of pulses, particularly red gram, has been examined. The textural changes in irradiated pulses in terms of softening is measured by a texturometer, Radiation (1 Mrad) processing of pulses resulted in reduction of cooking time varying from 8 to 39%, red gram showing the maximum reduction. Initial higher hydration rate on soaking and cooking, stabilized on prolonged cooking and resulted in better and uniform texture of irradiated red gram. In the uncooked, irradiated (1 Mrad) sample, destruction of riboflavin was negligible, whereas thiamine and niacin showed about 7% loss. However, the vitamins were retained better in the samples irradiated and then cooked, compared to the corresponding control ones.

  11. XPS analysis of PE and EVA samples irradiated at different γ-doses

    Science.gov (United States)

    Dorey, Samuel; Gaston, Fanny; Marque, Sylvain R. A.; Bortolotti, Benjamin; Dupuy, Nathalie

    2018-01-01

    The principal plastic materials used for the fluid contact and storage in the biopharmaceutical industry are mainly made up of semi-crystalline polymers, polyolefins, PVC, Siloxane and PET. The polyethylene (PE) and the polypropylene (PP) are often used as fluid contact in multi-layer materials like films. As one sterilisation way of single-use plastic devices used in medical and pharmaceutical fields can take place via γ-irradiation, the effect of sterilization on plastics must be investigated. The irradiation process leads to the production of radicals, which can generate changes in the polymer structure and on the polymer surface. It is well known that the presence of oxygen with free radicals precede the generation of peroxide species so called ROS (reactive oxygen species) which are highly reactive. The purpose of this work is to investigate the γ-rays impact on the surface of PE (polyethylene) and EVA (polyethylene vinyl alcohol) based films when ionized at different doses. X-ray Photoelectron Spectroscopy (XPS) was applied to determine the surface compositions of the polymers to highlight the different chemical moieties generated during the γ-irradiation process and to monitor the potential presence of the ROS.

  12. Acceptability of minimally processed and irradiated pineapple and watermelon among Brazilian consumers

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Cecilia Geraldes; Aragon-Alegro, Lina Casale; Behrens, Jorge Herman; Oliveira Souza, Katia Leani [Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Av. Prof. Lineu Prestes, 580 B.14, 05508-900 Sao Paulo, SP (Brazil); Martins Vizeu, Dirceu; Hutzler, Beatriz Weltman [Embrarad Ltda. Av. Cruzada Bandeirante, 269, 06700-000 Cotia, SP (Brazil); Teresa Destro, Maria [Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Av. Prof. Lineu Prestes, 580 B.14, 05508-900 Sao Paulo, SP (Brazil); Landgraf, Mariza [Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of Sao Paulo, Av. Prof. Lineu Prestes, 580 B.14, 05508-900 Sao Paulo, SP (Brazil)], E-mail: landgraf@usp.br

    2008-06-15

    This study aimed at evaluating the acceptance of MP watermelon and pineapple exposed to 1.0 and 2.5 kGy compared to non-irradiated samples. No significant differences were observed in liking between irradiated and non-irradiated samples, and also between doses of 1.0 and 2.5 kGy. Significant differences in sourness (pineapple) or sweetness (watermelon) and between intention of purchase of irradiated and non-irradiated fruits were not observed as well. Results showed that MP watermelon and pineapple could be irradiated with doses up to 2.5 kGy without significant changes in acceptability.

  13. Acceptability of minimally processed and irradiated pineapple and watermelon among Brazilian consumers

    International Nuclear Information System (INIS)

    Martins, Cecilia Geraldes; Aragon-Alegro, Lina Casale; Behrens, Jorge Herman; Oliveira Souza, Katia Leani; Martins Vizeu, Dirceu; Hutzler, Beatriz Weltman; Teresa Destro, Maria; Landgraf, Mariza

    2008-01-01

    This study aimed at evaluating the acceptance of MP watermelon and pineapple exposed to 1.0 and 2.5 kGy compared to non-irradiated samples. No significant differences were observed in liking between irradiated and non-irradiated samples, and also between doses of 1.0 and 2.5 kGy. Significant differences in sourness (pineapple) or sweetness (watermelon) and between intention of purchase of irradiated and non-irradiated fruits were not observed as well. Results showed that MP watermelon and pineapple could be irradiated with doses up to 2.5 kGy without significant changes in acceptability

  14. Acceptability of minimally processed and irradiated pineapple and watermelon among Brazilian consumers

    Science.gov (United States)

    Martins, Cecília Geraldes; Aragon-Alegro, Lina Casale; Behrens, Jorge Herman; Oliveira Souza, Kátia Leani; Martins Vizeu, Dirceu; Hutzler, Beatriz Weltman; Teresa Destro, Maria; Landgraf, Mariza

    2008-06-01

    This study aimed at evaluating the acceptance of MP watermelon and pineapple exposed to 1.0 and 2.5 kGy compared to non-irradiated samples. No significant differences were observed in liking between irradiated and non-irradiated samples, and also between doses of 1.0 and 2.5 kGy. Significant differences in sourness (pineapple) or sweetness (watermelon) and between intention of purchase of irradiated and non-irradiated fruits were not observed as well. Results showed that MP watermelon and pineapple could be irradiated with doses up to 2.5 kGy without significant changes in acceptability.

  15. Design and building of a homemade sample changer for automation of the irradiation in neutron activation analysis technique; Diseno y construccion de un prototipo de intercambiador para la automatizacion de la tecnica de analisis por activacion neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Gago, Javier; Hernandez, Yuri; Baltuano, Oscar; Bedregal, Patricia [Direccion de Investigacion y Desarrollo, Instituto Peruano de Energia Nuclear, Lima (Peru); Lopez, Yon [Universidad Nacional de Ingenieria, Lima (Peru); Urquizo, Rafael [Universidad Tecnologica del Peru, Lima (Peru)

    2014-07-01

    Because the RP-10 research reactor operates during weekends, it was necessary to design and build a sample changer for irradiation as part of the automation process of neutron activation analysis technique. The device is formed by an aluminum turntable disk which can accommodate 19 polyethylene capsules, containing samples to be sent using the pneumatic transfer system from the laboratory to the irradiation position. The system is operate by a control switchboard to send and return capsules in a variable preset time and by two different ways, allowing the determination of short, medium and long lived radionuclides. Also another mechanism is designed called 'exchange valve' for changing travel paths (pipelines) allowing the irradiated samples to be stored for a longer time in the reactor hall. The system design has allowed complete automation of this technique, enabling the irradiation of samples without the presence of an analyst. The design, construction and operation of the device is described and presented in this article. (authors).

  16. Building lab-scale x-ray tube based irradiators

    International Nuclear Information System (INIS)

    Haff, Ron; Jackson, Eric; Gomez, Joseph; Light, Doug; Follett, Peter; Simmons, Greg; Higbee, Brad

    2016-01-01

    Here we report the use of x-ray tube based irradiators as alternatives to gamma sources for laboratory scale irradiation. Irradiators were designed with sample placement in closest possible proximity to the source, allowing high dose rates for small samples. Designs using 1000 W x-ray tubes in single tube, double tube, and four tube configurations are described, as well as various cabinet construction techniques. Relatively high dose rates were achieved for small samples, demonstrating feasibility for laboratory based irradiators for research purposes. Dose rates of 9.76, 5.45, and 1.7 Gy/min/tube were measured at the center of a 12.7 cm container of instant rice at 100 keV, 70 keV, and 40 keV, respectively. Dose uniformity varies dramatically as the distance from source to container. For 2.54 cm diameter sample containers containing adult Navel Orangeworm, dose rates of 50–60 Gy/min were measured in the four tube system. - Highlights: • X-ray is demonstrated as an alternative to gamma for lab-based irradiation. • Cabinets using one, two, and four 1000 W tubes are reported. • Dose rate of 9.8 Gy/min/tube at the center of a 12.7 cm container of instant rice. • Dose uniformity varies dramatically as the distance from source to container.

  17. Gas chromatographic/mass spectrometric and microbiological analyses on irradiated chicken

    Science.gov (United States)

    Parlato, A.; Calderaro, E.; Bartolotta, A.; D'Oca, M. C.; Giuffrida, S. A.; Brai, M.; Tranchina, L.; Agozzino, P.; Avellone, G.; Ferrugia, M.; Di Noto, A. M.; Caracappa, S.

    2007-08-01

    Ionizing radiation is widely used as treatment technique for food preservation. It involves among others reduction of microbial contamination, disinfestations, sprout inhibition and extension of shelf life of food. However, the commercialization of irradiated food requires the availability of reliable methods to identify irradiated foodstuffs. In this paper, we present results on the application to irradiated chicken of this method, based on the detection, in muscle and skin samples, of the peaks of ions 98 Da and 112 Da, in a ratio approximately 4:1, typical of radiation induced 2-dodecylcyclobutanones (2-DCB). Aim of the work was also to study the time stability of the measured parameters in samples irradiated at 3 and 5 kGy, and to verify the efficacy of the treatment from a microbiological point of view. Our results show that, one month after irradiation at 3 kGy, the method is suitable using the skin but not the muscle, while the measured parameters are detectable in both samples irradiated at 5 kGy. The microbial population was substantially reduced even at 3 kGy.

  18. Gas chromatographic/mass spectrometric and microbiological analyses on irradiated chicken

    Energy Technology Data Exchange (ETDEWEB)

    Parlato, A. [Dipartimento di Ingegneria Nucleare, Universita di Palermo, Viale delle Scienze, Edificio 6, 90100 Palermo (Italy); Calderaro, E. [Dipartimento di Ingegneria Nucleare, Universita di Palermo, Viale delle Scienze, Edificio 6, 90100 Palermo (Italy); Bartolotta, A. [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy)]. E-mail: antonio.bartolotta@unipa.it; D' Oca, M.C. [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Giuffrida, S.A. [Dipartimento Farmacochimico, Tossicologico e Biologico, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Brai, M. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90100 Palermo (Italy); Tranchina, L. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90100 Palermo (Italy); Agozzino, P. [Dipartimento di Chimica e Tecnologie Farmaceutiche, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Avellone, G. [Dipartimento di Chimica e Tecnologie Farmaceutiche, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Ferrugia, M. [Dipartimento di Chimica e Tecnologie Farmaceutiche, Universita di Palermo, via Archirafi 32, 90123 Palermo (Italy); Di Noto, A.M. [Istituto Zooprofilattico Sperimentale della Sicilia ' A.Mirri' , Palermo (Italy); Caracappa, S. [Istituto Zooprofilattico Sperimentale della Sicilia ' A.Mirri' , Palermo (Italy)

    2007-08-15

    Ionizing radiation is widely used as treatment technique for food preservation. It involves among others reduction of microbial contamination, disinfestations, sprout inhibition and extension of shelf life of food. However, the commercialization of irradiated food requires the availability of reliable methods to identify irradiated foodstuffs. In this paper, we present results on the application to irradiated chicken of this method, based on the detection, in muscle and skin samples, of the peaks of ions 98 Da and 112 Da, in a ratio approximately 4:1, typical of radiation induced 2-dodecylcyclobutanones (2-DCB). Aim of the work was also to study the time stability of the measured parameters in samples irradiated at 3 and 5 kGy, and to verify the efficacy of the treatment from a microbiological point of view. Our results show that, one month after irradiation at 3 kGy, the method is suitable using the skin but not the muscle, while the measured parameters are detectable in both samples irradiated at 5 kGy. The microbial population was substantially reduced even at 3 kGy.

  19. Gas chromatographic/mass spectrometric and microbiological analyses on irradiated chicken

    International Nuclear Information System (INIS)

    Parlato, A.; Calderaro, E.; Bartolotta, A.; D'Oca, M.C.; Giuffrida, S.A.; Brai, M.; Tranchina, L.; Agozzino, P.; Avellone, G.; Ferrugia, M.; Di Noto, A.M.; Caracappa, S.

    2007-01-01

    Ionizing radiation is widely used as treatment technique for food preservation. It involves among others reduction of microbial contamination, disinfestations, sprout inhibition and extension of shelf life of food. However, the commercialization of irradiated food requires the availability of reliable methods to identify irradiated foodstuffs. In this paper, we present results on the application to irradiated chicken of this method, based on the detection, in muscle and skin samples, of the peaks of ions 98 Da and 112 Da, in a ratio approximately 4:1, typical of radiation induced 2-dodecylcyclobutanones (2-DCB). Aim of the work was also to study the time stability of the measured parameters in samples irradiated at 3 and 5 kGy, and to verify the efficacy of the treatment from a microbiological point of view. Our results show that, one month after irradiation at 3 kGy, the method is suitable using the skin but not the muscle, while the measured parameters are detectable in both samples irradiated at 5 kGy. The microbial population was substantially reduced even at 3 kGy

  20. Quality of jinchen orange juice treated with irradiation and pasteurization

    International Nuclear Information System (INIS)

    Qiao Yu; Cheng Wei; Wang Shaohua; Xiong Guangquan; Liao Li; Chen Xueling; Fan Gang; Pan Siyi

    2010-01-01

    Jinchen orange juice was treated by pasteurization and irradiation (1.4, 2.8 and 5.6 kGy) to study the effects of sterilization methods on quality of orange juice. The volatile compounds were analyzed by solid phase micro-extraction method combined with GC-MS. The juice color, pH and Vc content were determined, and sensory evaluation of the juice were evaluated. The results showed a total of 54, 47, 57, 55, 53 kinds of compounds were detected in fresh juice, pasteurized juice and 3 irradiated juices, respectively. The irradiated juices had bigger peak area of volatile compounds than pasteurized juice,and the biggest peak area was found in 2.8 kGy irradiation sample. β - myrcene, D - limonene and γ-terpinene, which were the characteristic aroma compounds in orange juice, were detected a higher level in irradiation sample than pasteurization. Vc content and aroma decreased after all treatments. The sample after 1.4 kGy treatment showed highest score in sensory evaluation. It was concluded that low dose irradiation could be used in sterilization processing of orange juice. (authors)

  1. Opto-structural characterization of gamma irradiated Bayfol polymer track detector

    Energy Technology Data Exchange (ETDEWEB)

    Tayel, A. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Zaki, M.F., E-mail: moha1016@yahoo.com [Experimental Nuclear Physics Department, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Abu Zaabal, Cairo (Egypt); El Basaty, A.B. [Physics Department, Faculty of Industrial Education, Helwan University, Cairo (Egypt); Hegazy, Tarek M. [Physics Department, College of Women for Arts, Science and Education, Ain Shams University, Cairo (Egypt)

    2013-11-15

    Bayfol CR 1-4 is one of polymeric solid state nuclear track detector which has numerous applications due to its outstanding optical, mechanical, thermal and electrical properties. In the present study, Bayfol polymer is irradiated with different doses of gamma rays ranging from 0 to 1000 KGy. The effects of gamma irradiations on the optical, structural and chemical properties of Bayfol were studied using Ultraviolet and visible (UV/Vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The UV–Vis spectra of irradiated samples show that the absorption edge is shifted towards longer wavelength comparing to pristine sample spectrum. This behavior indicates that there is a decrease in the band gap after irradiation. The maximum decrease in the band gap is about 0.8 eV. The XRD patterns of amorphous halo of pristine and irradiated samples show a fluctuation of integrated intensity of amorphous halo. This indicates a change in the structure due to gamma irradiation. In order to understand that structure change mechanism, we used the FTIR spectroscopy.

  2. Analysis of the radiolytic products on high-dose irradiated food and packing materials

    International Nuclear Information System (INIS)

    Kim, Kyong Su; Shim, Sung Lye; Chung, In Sun

    2010-04-01

    The aims of this study were to prepare the government approval for the extension of food irradiation item to food or its products, to promote the industrial application of radiation technology, and to apply basic data in policy for introduction of irradiation. The change of hydrocarbons by irradiation was evaluated for the detection of irradiated meat. The results showed that hydrocarbons were detected in all of irradiated samples, but these hydrocarbons were not detected in non-irradiated samples. There were no difference between vacuum and N 2 - packaging. According to fatty acid compounds and degradation pathway of beef and pork, it could be deliberated that a great amount of produced hydrocarbons such as 8-heptadenene and 1,7-hexadecadien were able to be used as identification factor of irradiated meat. Effects of γ-irradiation on the volatile organic compounds in agricultural products were determined by analyzing changes of volatile composition. The composition of volatile organic compounds were little changed, but few specific compounds induced by γ-irradiation were identified. The variations of concentration in irradiated samples identified in this study could be due to the radiation sensitivity of compounds with the dose used. Effects of γ-irradiation on the volatile compounds in packaging materials were determined by analyzing changes of volatile composition. In polyethylene and polypropylene, 1,3-DBB was identified only in irradiated samples. Levels of 1,3-DBB increased with increasing irradiation doses. These results suggest may be useful in evaluation of γ-irradiation effects on food packaging materials

  3. Analysis of the radiolytic products on high-dose irradiated food and packing materials

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyong Su; Shim, Sung Lye; Chung, In Sun [Chosun University, Gwangju (Korea, Republic of)

    2010-04-15

    The aims of this study were to prepare the government approval for the extension of food irradiation item to food or its products, to promote the industrial application of radiation technology, and to apply basic data in policy for introduction of irradiation. The change of hydrocarbons by irradiation was evaluated for the detection of irradiated meat. The results showed that hydrocarbons were detected in all of irradiated samples, but these hydrocarbons were not detected in non-irradiated samples. There were no difference between vacuum and N{sub 2}- packaging. According to fatty acid compounds and degradation pathway of beef and pork, it could be deliberated that a great amount of produced hydrocarbons such as 8-heptadenene and 1,7-hexadecadien were able to be used as identification factor of irradiated meat. Effects of {gamma}-irradiation on the volatile organic compounds in agricultural products were determined by analyzing changes of volatile composition. The composition of volatile organic compounds were little changed, but few specific compounds induced by {gamma}-irradiation were identified. The variations of concentration in irradiated samples identified in this study could be due to the radiation sensitivity of compounds with the dose used. Effects of {gamma}-irradiation on the volatile compounds in packaging materials were determined by analyzing changes of volatile composition. In polyethylene and polypropylene, 1,3-DBB was identified only in irradiated samples. Levels of 1,3-DBB increased with increasing irradiation doses. These results suggest may be useful in evaluation of {gamma}-irradiation effects on food packaging materials

  4. Improvement of Microbiological and Sensory Quality of Fried Seasoning Anchovy Fish Snack by Gamma Irradiation

    International Nuclear Information System (INIS)

    Prakongsil, Panchalee; Neramitmansook, Naruemon; Phianphak, Wannipa; Kaewchoung, Pravait

    2009-07-01

    Full text: Microbiological and sensory qualities of gamma irradiated fried seasoning anchovy fish snack were evaluated. The samples were packed in polyethylene bags and stored under three different conditions. In Group I, the fish snacks were vacuum-packed and stored at room temperature. In Group II, the bags were sealed normally and stored at room temperature. Group-III samples were packed as in Group II but they were stored at 18 O C. Gamma irradiation was applied at the minimum absorbed dose of 2.0 kGy. Microbiological qualities were evaluated at 1, 2 and 3 months post irradiation. At three months, unirradiated samples from all three storage conditions were found with their total bacterial counts exceeding the limit for the quality standard of the Ministry of Industry (>10 3 cfu/g), while the total bacterial counts from irradiated samples were 1 log cycle fewer than those from unirradiated samples. The total yeast and mold counts produced by irradiated samples were within the limit throughout the three-month storage for all three conditions. E. coli, Salmonella spp., S. aureus and Clostridium spp. were not found under all storage conditions for both irradiated and unirradiated samples. No significant differences in the sensory quality were observed between irradiated and unirradiated samples for all three conditions. Although irradiated fried seasoning anchovy fish snack in a vacuum pack yielded better microbiological qualities than irradiated samples in a normal-sealed pack, samples in a normal-sealed pack stored at room temperature would be more appropriate for commercial production when production costs were considered

  5. Measurement of volatile evolution from polyurethane induced by accelerated ion beam irradiation

    International Nuclear Information System (INIS)

    Murphy, J.J.

    2003-01-01

    Irradiation of polymer samples using an accelerated beam of He 2+ ions passed through a 10μm thick window of havar foil has been performed. Such irradiation simulates the effects of large α radiation doses, on a vastly reduced time-scale. Analysis of volatiles evolved during irradiation is performed by a residual gas analyser (RGA), which is located close to the sample chamber. Presented in this paper are the results obtained during a radiation study on polyester/MDI based polyurethane materials. During high dose rate irradiation a number of high mass species were observed. A comparison between two similar polyurethanes formulated with slightly different polyesters indicated some differences. They were, however, too minor to link to specific degradation mechanisms. The dominant degradation products evident to the RGA at low dose rates were H 2 , CO and CO 2 . A series of polyurethane samples previously conditioned by γ irradiation at doses between 0 and 5MGy were irradiated in the ion beam. Identification of differences in trends in the rates of volatile evolution between these samples indicated the precise vacuum conditions at the time of irradiation had a major influence. There was also an indication that the surface of the sample had a small effect on rates of volatile evolution. Comparative plots of CO and CO 2 evolution for a series of 1MGy irradiations indicated variations in behaviour between samples with different γ doses. Evolution during the first 1MGy was inhibited for the unirradiated sample, the extent of inhibition diminished with increasing γ dose and was no longer evident in a sample with 1.5MGy γ dose. H 2 does not show an equivalent inhibition. Evidence for a low dose crosslinking reaction is put forward as a reason for the inhibition. Chemical reaction mechanisms are postulated and used to explain differences in the behaviour observed

  6. Dose mapping in category I irradiators

    International Nuclear Information System (INIS)

    Mondal, Sandip; Shinde, S.H.; Mhatre, S.G.V.

    2012-01-01

    Category I irradiators such as Gamma Chambers and Blood Irradiators are compact self shielded, dry source storage gamma irradiators offering irradiation volume of few hundred cubic centimeters. In the present work, dose distribution profiles along the central vertical plane of the irradiation volume of Gamma Chamber 900 and Blood Irradiator 2000 were measured using Fricke, FBX, and alanine dosimeters. Measured dose distribution profiles in Gamma Chamber 900 differed from the typical generic dose distribution pattern whereas that in Blood Irradiator 2000 was in agreement with the typical pattern. All reagents used were of analytical reagent grade and were used without further purification. Preparation and dose estimations of Fricke and FBX were carried out as recommended. Alanine pellets were directly placed in precleaned polystyrene container having dimensions 6.5 mm o.d., 32 mm height and 3 mm wall thickness. For these dosimeters, dose measurements were made using e-scan Bruker BioSpin alanine dedicated ESR spectrometer. Specially designed perspex jigs were used during irradiation in Gamma Chamber 900 and Blood Irradiator 2000. These jigs provided the reproducible geometry during irradiation, Absorbance measurements were made using a spectrophotometer calibrated as per the recommended procedure. In Gamma Chamber 900, there is a dose distribution variation of about 34% from top to the center, 18% from center to the bottom, and 15% from center to the periphery. Such a dose distribution profile is largely deviating from the typical profile wherein 15% variation is observed from center to the periphery on all sides. Further investigation showed that there was a nonalignment in the source and sample chamber. However, in Blood Irradiator 2000, there is a dose distribution variation of about 20% from top to the center, 15% from center to the bottom, and 12% from center to the periphery. This pattern is very much similar to the typical profile. Hence it is recommended

  7. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

  8. Coexistence of both gyroid chiralities in individual butterfly wing scales of Callophrys rubi.

    Science.gov (United States)

    Winter, Benjamin; Butz, Benjamin; Dieker, Christel; Schröder-Turk, Gerd E; Mecke, Klaus; Spiecker, Erdmann

    2015-10-20

    The wing scales of the Green Hairstreak butterfly Callophrys rubi consist of crystalline domains with sizes of a few micrometers, which exhibit a congenitally handed porous chitin microstructure identified as the chiral triply periodic single-gyroid structure. Here, the chirality and crystallographic texture of these domains are investigated by means of electron tomography. The tomograms unambiguously reveal the coexistence of the two enantiomeric forms of opposite handedness: the left- and right-handed gyroids. These two enantiomers appear with nonequal probabilities, implying that molecularly chiral constituents of the biological formation process presumably invoke a chiral symmetry break, resulting in a preferred enantiomeric form of the gyroid structure. Assuming validity of the formation model proposed by Ghiradella H (1989) J Morphol 202(1):69-88 and Saranathan V, et al. (2010) Proc Natl Acad Sci USA 107(26):11676-11681, where the two enantiomeric labyrinthine domains of the gyroid are connected to the extracellular and intra-SER spaces, our findings imply that the structural chirality of the single gyroid is, however, not caused by the molecular chirality of chitin. Furthermore, the wing scales are found to be highly textured, with a substantial fraction of domains exhibiting the directions of the gyroid crystal aligned parallel to the scale surface normal. Both findings are needed to completely understand the photonic purpose of the single gyroid in gyroid-forming butterflies. More importantly, they show the level of control that morphogenesis exerts over secondary features of biological nanostructures, such as chirality or crystallographic texture, providing inspiration for biomimetic replication strategies for synthetic self-assembly mechanisms.

  9. The chiral structure of porous chitin within the wing-scales of Callophrys rubi.

    Science.gov (United States)

    Schröder-Turk, G E; Wickham, S; Averdunk, H; Brink, F; Fitz Gerald, J D; Poladian, L; Large, M C J; Hyde, S T

    2011-05-01

    The structure of the porous three-dimensional reticulated pattern in the wing scales of the butterfly Callophrys rubi (the Green Hairstreak) is explored in detail, via scanning and transmission electron microscopy. A full 3D tomographic reconstruction of a section of this material reveals that the predominantly chitin material is assembled in the wing scale to form a structure whose geometry bears a remarkable correspondence to the srs net, well-known in solid state chemistry and soft materials science. The porous solid is bounded to an excellent approximation by a parallel surface to the Gyroid, a three-periodic minimal surface with cubic crystallographic symmetry I4₁32, as foreshadowed by Stavenga and Michielson. The scale of the structure is commensurate with the wavelength of visible light, with an edge of the conventional cubic unit cell of the parallel-Gyroid of approximately 310 nm. The genesis of this structure is discussed, and we suggest it affords a remarkable example of templating of a chiral material via soft matter, analogous to the formation of mesoporous silica via surfactant assemblies in solution. In the butterfly, the templating is achieved by the lipid-protein membranes within the smooth endoplasmic reticulum (while it remains in the chrysalis), that likely form cubic membranes, folded according to the form of the Gyroid. The subsequent formation of the chiral hard chitin framework is suggested to be driven by the gradual polymerisation of the chitin precursors, whose inherent chiral assembly in solution (during growth) promotes the formation of a single enantiomer. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Effect of electron beam irradiation on quality of fresh chilled pork

    International Nuclear Information System (INIS)

    Shang Yibin; Gao Meixu; Li Shurong; Pei Ying; Wang Zhidong

    2013-01-01

    The effects of electron beam irradiation on nutrient quality, lipid oxidation and sensory quality of fresh chilled pork were investigated. Fresh chilled pork whose fat to muscle ratio was 1 : 6 was grounded and packaged, and then irradiated at doses of 0, 2.0, 3.8, 6.2, 8.3 and 10.5 kGy. The contents of fat andprotein, chromaticity, sensory characteristics, lipid oxidation index of TBARS value, POV, diene value of irradiated and unirradiated samples were measured. The results showed that there were no significant differences (5% level) in content of proteinand fat between irradiated and control samples, but irradiation could significantly increase TBARS value and POV. EB irradiation enhanced the increase of total diene value. The samples treated with 3.8 and 6.2 kGy showed good color during storage. There were no significant differences in sensory characteristics among different EB doses. It is concluded that 4-6 kGy EB irradiation, which is effective for decontamination, shows no significant effect on qualities of fresh chilled pork. (authors)

  11. Boron ion irradiation induced structural and surface modification of glassy carbon

    International Nuclear Information System (INIS)

    Kalijadis, Ana; Jovanović, Zoran; Cvijović-Alagić, Ivana; Laušević, Zoran

    2013-01-01

    The incorporation of boron into glassy carbon was achieved by irradiating two different types of targets: glassy carbon polymer precursor and carbonized glassy carbon. Targets were irradiated with a 45 keV B 3+ ion beam in the fluence range of 5 × 10 15 –5 × 10 16 ions cm −2 . For both types of targets, the implanted boron was located in a narrow region under the surface. Following irradiation, the polymer was carbonized under the same condition as the glassy carbon samples (at 1273 K) and examined by Raman spectroscopy, temperature programmed desorption, hardness and cyclic voltammetry measurements. Structural analysis showed that during the carbonization process of the irradiated polymers, boron is substitutionally incorporated into the glassy carbon structure, while for irradiated carbonized glassy carbon samples, boron irradiation caused an increase of the sp 3 carbon fraction, which is most pronounced for the highest fluence irradiation. Further analyses showed that different nature of boron incorporation, and thus changed structural parameters, are crucial for obtaining glassy carbon samples with modified mechanical, chemical and electrochemical properties over a wide range

  12. Crescimento inicial do cafeeiro Rubi em resposta a doses de nitrogênio, fósforo e potássio e a regimes hídricos Initial growth of Rubi coffee plant in response to nitrogen, phosphorus and potassium and water regimes

    Directory of Open Access Journals (Sweden)

    Rodrigo Barbosa Nazareno

    2003-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o crescimento da parte aérea do cafeeiro (Coffea arabica L. cultivar Rubi MG 1192 submetido a três doses de N, P e K e dois regimes hídricos durante o primeiro ano após o transplante, em 20 de novembro de 2000. O crescimento da planta foi avaliado aos 134, 196, 236, 284, 334 e 383 dias após o transplante (dat. Houve resposta ao N e ao K no crescimento em número de ramos plagiotrópicos por planta, ao passo que no número de nós com gemas por planta, observou-se resposta apenas ao nitrogênio. Não houve resposta ao N, P e K no aumento da massa seca da parte aérea e no índice de área foliar. Além de mostrar efeito significativo no crescimento do cafeeiro, a irrigação antecipou o rápido crescimento para julho (236 dat proporcionando plantas mais vigorosas. Nas plantas não-irrigadas, o rápido crescimento ocorreu em meados de outubro (334 dat. Entretanto, a irrigação não impediu a queda na taxa de crescimento durante o inverno. O desenvolvimento das gemas em frutos ou ramos secundários nas plantas não-irrigadas alterou a distribuição de matéria seca e reduziu o crescimento do caule, ramos e folhas.The objective of this work was to evaluate shoot growth of coffee trees (Coffea arabica L. cultivar Rubi MG 1192 under three N, P and K doses and two water regimes during the first year after transplanting, starting on the 20th November 2000. The growth was evaluated at 134, 196, 236, 284, 334 and 383 days after transplanting (DAT. Nitrogen and K affected the number of plagiotropic branches per plant. Nevertheless, only N affected the number of nodes with axillary buds. There was no growth response to N, P, and K in terms of the total shoot dry mass and leaf area index during the experimental period. Irrigated treatments presented the best plant growth results, provided more vigorous plants and anticipated the fast growth phase to July (236 DAT, but could not avoid growth rate decrease during

  13. Utilization of irradiation on food preservation

    International Nuclear Information System (INIS)

    Cho, Han Ok; Byun, Myung Woo; Kwon, Joong Ho; Kim, Suk Won; Yang, Jae Sung; Cha, Bo Sook; Park, Ki Bum

    1987-12-01

    The present project was intended to ascertain the efficacy of irradiation both in the decontamination and storeability of mixed condiments for convenience food and in the long-term preservation of a Kimchi. Based upon the preliminary studies, irradiated sample with doses at 1-3 kGy were evaluated during the storage for 30 days at 10 deg C from the points of view of microbiological (total aerobic bacteria, lactic acid bacteria, yeasts and molds, and coliforms), physicochemical (pH, total acidity, volatile acid, reducing sugar, ascorbic acid, and texture) and organoleptic qualities. Besides, the combined effect of irradiation with heating on the storeability was investigated for five species of the lactic acid bacteria associated with the Kimchi fermentation. Under the room temperature storage conditions, physicochemical qualities of the irradiated samples were evaluated by determining pH, rancidity (TBA number), proximate composition, amino nitrogen, amino acid, and color changes. In the overall evaluation of sensory quality for the irradiated Kimchi, the nonirradiated control group was inedible after 15 days of storage, whereas 2-3 kGy irradiation could prolong the storage-life of the Kimchi over 2 times compared with the nonirradiated control, showing the good sensory quality even after 30 days of storage. In comparative effects of irradiation and ethylene oxide both treatments affected more or less rancidity, color, and amino acid content, but less than 10 kGy irradiation was shown to be safer than ethylene oxide fumigation. Form the foregoing results, it can be concluded that if a selective method could be applied to the radiation sterilization of minor ingredients capable of mainly contaminating the mixed condiments, even lower doses of irradiation should be effective for the microbial control. (Author)

  14. Antioxidant activity of extract from gamma irradiated grape (Psidium guajava L.) seeds

    International Nuclear Information System (INIS)

    Abdeldaiem, M. H.; Ali, H.G.M.; Nasr, E.H.

    2012-01-01

    The objective this study was to study the antioxidant activity efficiency of extracts from irradiated defatted guava (Psidium guajava L.) seeds at dose levels of 0, 2, 4 and 6 kGy. The non-irradiated and irradiated defatted guava seeds samples were extracted with acetone: water: acetic acid (90:9.5:0.5). Immediately after irradiation, the antioxidant activity was studied. Gas chromatographic-Mass spectrum was applied to identify and quantify the constituents (%) of extracts and the amino acids composition was determined in all samples under investigation of defatted guava seeds powder. The measurements of the antioxidant activity, using a γ-carotene-linoleate model system and radical scavenging capacity effect on 2, 2-diphenyl-1- picrylhydrazyl (DPPH) radical, was determined in the extracts of non-irradiated and irradiated defatted guava seeds powder. Meanwhile, noodles (homemade strips macaroni) were prepared from blends of 72% wheat flour containing 0, 2.5, 5 and 7.5% levels of non-irradiated defatted guava seeds powder. The results showed that samples of extracts from non-irradiated and irradiated defatted guava seeds had contained a considerable total polyphenolic compounds and marked scavenging activity on DPHH radical. On the other hand , the gas chromatography (GC) and mass spectroscopy (MS) separation technique led to identification of 26 components the of extract non-irradiated and irradiated samples. Also, the data revealed that guava seeds powder samples under investigation passes the most important essential amino acids and for human health such as trace elements iron, zinc and manganese. Noodles prepared from 2.5% level of guava seeds powder-wheat flour blend had high acceptable quality. Thus, guava seeds, a waste from guava industry can be utilized improved nutritional properties of noodles or used its extracts as natural antioxidant in food industry field

  15. Analysis of volatile organic compounds of ‘Fuji’ apples following electron beam irradiation and storage

    International Nuclear Information System (INIS)

    Song, Hyun-Pa; Shim, Sung-Lye; Lee, Sun-Im; Kim, Dong-Ho; Kwon, Joong-Ho; Kim, Kyong-Su

    2012-01-01

    The volatile organic compounds of non-irradiated and electron-beam irradiated ‘Fuji’ apples (Malus domestica Borkh.) at 0, 0.5, and 1 kGy were isolated through simultaneous distillation extractions and analyzed using gas chromatograph–mass spectrometry. A total of 53 volatile organic compounds were characterized in 0 and 1 kGy irradiated samples, whereas two more compounds related to ketone and terpenoid group were identified in 0.5 kGy irradiated samples. The contents of volatile compounds were 24.33, 36.49, and 35.28 mg/kg in 0, 0.5, and 1 kGy irradiated samples, respectively. The major compounds identified were butanol, hexanal, [E]-2-hexenal, and hexanol in all samples. The relative content of alcohol increased after 30 days of storage in all samples, whereas that of aldehyde decreased. Although the contents of some volatile compounds were changed by electron-beam irradiation, the total yield and major flavor compounds of irradiated ‘Fuji’ apples were similar to, or even greater than, those of the control. Therefore, the application of e-beam irradiation if required for microbial decontamination of ‘Fuji’ apples is an acceptable method as it does not bring about any major quantitative changes of volatile organic compounds. - Highlights: ► We analyzed the volatile organic compounds of electron beam irradiated Fuji apples. ► The major compounds of samples were butanol, hexanal, [E]-2-hexenal, and hexanol. ► The contents of major flavor compounds of non-irradiated and irradiated samples were similar.

  16. Identification of gamma-irradiated fruit juices by EPR spectroscopy

    Science.gov (United States)

    Aleksieva, K. I.; Dimov, K. G.; Yordanov, N. D.

    2014-10-01

    The results of electron paramagnetic resonance (EPR) study on commercially available juices from various fruits and different fruit contents: 25%, 40%, 50%, and 100%, homemade juices, nectars and concentrated fruit syrups, before and after gamma-irradiation are reported. In order to remove water from non- and irradiated samples all juices and nectars were filtered; the solid residue was washed with alcohol and dried at room temperature. Only concentrated fruit syrups were dried for 60 min at 40 °C in a standard laboratory oven. All samples under study show a singlet EPR line with g=2.0025 before irradiation with exception of concentrated fruit syrups, which are EPR silent. Irradiation of juice samples gives rise to complex EPR spectra which gradually transferred to "cellulose-like" EPR spectrum from 25% to 100% fruit content. Concentrated fruit syrups show typical "sugar-like" spectra due to added saccharides. All EPR spectra are characteristic and can prove radiation treatment. The fading kinetics of radiation-induced EPR signals were studied for a period of 60 days after irradiation.

  17. Gamma irradiation influence on physical properties of milk proteins

    International Nuclear Information System (INIS)

    Ciesla, K.; Salmieri, S.; Lacroix, M.; Le Tien, C.

    2004-01-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling

  18. Gamma irradiation influence on physical properties of milk proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ciesla, K. E-mail: kciesla@orange.ichtj.waw.pl; Salmieri, S.; Lacroix, M.; Le Tien, C

    2004-10-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and {beta}-sheets, in particular from increase of {beta}-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  19. Thermoluminescence method for detection of irradiated food

    International Nuclear Information System (INIS)

    Pinnioja, S.

    1998-01-01

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL

  20. Thermoluminescence method for detection of irradiated food

    Energy Technology Data Exchange (ETDEWEB)

    Pinnioja, S

    1998-12-31

    A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL