WorldWideScience

Sample records for sccmec elements obtained

  1. Characterization of a new SCCmec element in Staphylococcus cohnii.

    Directory of Open Access Journals (Sweden)

    Zhiyong Zong

    Full Text Available BACKGROUND: Many SCCmec elements of coagulase-negative staphylococci (CoNS could not be typed using multiplex PCR. Such a 'non-typable' SCCmec was encountered in a Staphylococcus cohnii isolate. METHODOLOGY/PRINCIPAL FINDINGS: The SCCmec type of methicillin-resistant S. cohnii clinical isolate WC28 could not be assigned using multiplex PCR. Newly-designed primers were used to amplify ccrA and ccrB genes. The whole SCCmec was obtained by three overlapping long-range PCR, targeting regions from left-hand inverted repeat (IRL to ccrA/B, from ccrA/B to mecA and from mecA to orfX. The region abutting IRL was identified using inverse PCR with self-ligated enzyme-restricted WC28 fragments as the template. WC28 SCCmec had a class A mec gene complex (mecI-mecR1-mecA. The ccrA and ccrB genes were closest (89.7% identity to ccrA(SHP of Staphylococcus haemolyticus strain H9 and to ccrB3 (90% identity of Staphylococcus pseudintermedius strain KM241, respectively. Two new genes potentially encoding AAA-type ATPase were found in J1 region and a ψTn554 transposon was present in J2 region, while J3 region was the same as many SCCmec of Staphylococcus aureus. WC28 SCCmec abutted an incomplete SCC element with a novel allotype of ccrC, which was closest (82% identity to ccrC1 allele 9 in Staphylococcus saprophyticus strain ATCC 15305. Only two direct target repeat sequences, one close to the 3'-end of orfX and the other abutting the left end of WC28 SCCmec, could be detected. CONCLUSIONS/SIGNIFICANCE: A new 35-kb SCCmec was characterized in a S. cohnii isolate, carrying a class A mec gene complex, new variants of ccrA5 and ccrB3 and two novel genes in the J1 region. This element is flanked by 8-bp perfect inverted repeats and is similar to type III SCCmec in S. aureus and a SCCmec in S. pseudintermedius but with different J1 and J3 regions. WC28 SCCmec was arranged in tandem with an additional SCC element with ccrC, SCC(WC28, but the two elements might have

  2. Characterization of a new SCCmec element in Staphylococcus cohnii.

    Science.gov (United States)

    Zong, Zhiyong; Lü, Xiaoju

    2010-11-17

    Many SCCmec elements of coagulase-negative staphylococci (CoNS) could not be typed using multiplex PCR. Such a 'non-typable' SCCmec was encountered in a Staphylococcus cohnii isolate. The SCCmec type of methicillin-resistant S. cohnii clinical isolate WC28 could not be assigned using multiplex PCR. Newly-designed primers were used to amplify ccrA and ccrB genes. The whole SCCmec was obtained by three overlapping long-range PCR, targeting regions from left-hand inverted repeat (IRL) to ccrA/B, from ccrA/B to mecA and from mecA to orfX. The region abutting IRL was identified using inverse PCR with self-ligated enzyme-restricted WC28 fragments as the template. WC28 SCCmec had a class A mec gene complex (mecI-mecR1-mecA). The ccrA and ccrB genes were closest (89.7% identity) to ccrA(SHP) of Staphylococcus haemolyticus strain H9 and to ccrB3 (90% identity) of Staphylococcus pseudintermedius strain KM241, respectively. Two new genes potentially encoding AAA-type ATPase were found in J1 region and a ψTn554 transposon was present in J2 region, while J3 region was the same as many SCCmec of Staphylococcus aureus. WC28 SCCmec abutted an incomplete SCC element with a novel allotype of ccrC, which was closest (82% identity) to ccrC1 allele 9 in Staphylococcus saprophyticus strain ATCC 15305. Only two direct target repeat sequences, one close to the 3'-end of orfX and the other abutting the left end of WC28 SCCmec, could be detected. A new 35-kb SCCmec was characterized in a S. cohnii isolate, carrying a class A mec gene complex, new variants of ccrA5 and ccrB3 and two novel genes in the J1 region. This element is flanked by 8-bp perfect inverted repeats and is similar to type III SCCmec in S. aureus and a SCCmec in S. pseudintermedius but with different J1 and J3 regions. WC28 SCCmec was arranged in tandem with an additional SCC element with ccrC, SCC(WC28), but the two elements might have integrated independently rather than constituted a composite. This study adds new

  3. Characterisation of SCCmec elements in methicillin-resistant Staphylococcus aureus isolated from burn patients.

    Science.gov (United States)

    Namvar, Amirmorteza Ebrahimzadeh; Afshar, Mastaneh; Asghari, Babak; Rastegar Lari, Abdolaziz

    2014-06-01

    Staphylococcus aureus is an important pathogen, especially in burn units all around the world. Because of the emergence of the β-lactam antibiotic-resistant strains since 1961, concern about the prevalence of methicillin-resistant S. aureus (MRSA) has increased in these units. Resistance to methicillin is mediated by penicillin-binding proteins (PBPs) that have enough affinity for binding to the β-lactam ring, but another kind of protein (PBP2α), which is encoded by the mecA gene, has a lower affinity for binding to these antibiotics. The mecA gene is transferred by SCCmec (staphylococcal cassette chromosome mec) as a mobile genetic element, exclusively found in the Staphylococcus genus. Identification of the frequency of the mecA gene, different SCCmec types and also its incidence may have benefit in surveillance prevention and control of MRSA strains in burn units. In this study, 40 S. aureus isolates were collected from patients hospitalised in Motahari burn center of Tehran, during 2012-2013. Conventional microbiological methods were applied and the confirmed isolates were stored at -20°C for molecular polymerase chain reaction (PCR) tests. The antibiotic resistance pattern was performed by disc diffusion method and finally the different SCCmec types were determined by specific primers. During this research, 40 isolates of S. aureus were collected from burn patients, of which (37.5%) of the specimens belonged to female patients and 62.5% to male patients. The aetiology of the burn was classified as follows: open flame (35%), liquid (32.5%), chemical (5%) and other (27.5%). By a disc diffusion method, no resistance pattern was observed to vancomycin and fosfomycin. Based on a multiplex PCR assay, the five different SCCmec types were detected as: 47.5% type III, 25% type IV, 10% type V, 10% type II and 7.5% type I. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  4. Emergence of Sequence Type 779 Methicillin-Resistant Staphylococcus aureus Harboring a Novel Pseudo Staphylococcal Cassette Chromosome mec (SCCmec)-SCC-SCCCRISPR Composite Element in Irish Hospitals

    Science.gov (United States)

    Kinnevey, Peter M.; Shore, Anna C.; Brennan, Grainne I.; Sullivan, Derek J.; Ehricht, Ralf; Monecke, Stefan; Slickers, Peter

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has been a major cause of nosocomial infection in Irish hospitals for 4 decades, and replacement of predominant MRSA clones has occurred several times. An MRSA isolate recovered in 2006 as part of a larger study of sporadic MRSA exhibited a rare spa (t878) and multilocus sequence (ST779) type and was nontypeable by PCR- and DNA microarray-based staphylococcal cassette chromosome mec (SCCmec) element typing. Whole-genome sequencing revealed the presence of a novel 51-kb composite island (CI) element with three distinct domains, each flanked by direct repeat and inverted repeat sequences, including (i) a pseudo SCCmec element (16.3 kb) carrying mecA with a novel mec class region, a fusidic acid resistance gene (fusC), and two copper resistance genes (copB and copC) but lacking ccr genes; (ii) an SCC element (17.5 kb) carrying a novel ccrAB4 allele; and (iii) an SCC element (17.4 kb) carrying a novel ccrC allele and a clustered regularly interspaced short palindromic repeat (CRISPR) region. The novel CI was subsequently identified by PCR in an additional 13 t878/ST779 MRSA isolates, six from bloodstream infections, recovered between 2006 and 2011 in 11 hospitals. Analysis of open reading frames (ORFs) carried by the CI showed amino acid sequence similarity of 44 to 100% to ORFs from S. aureus and coagulase-negative staphylococci (CoNS). These findings provide further evidence of genetic transfer between S. aureus and CoNS and show how this contributes to the emergence of novel SCCmec elements and MRSA strains. Ongoing surveillance of this MRSA strain is warranted and will require updating of currently used SCCmec typing methods. PMID:23147725

  5. Emergence of sequence type 779 methicillin-resistant Staphylococcus aureus harboring a novel pseudo staphylococcal cassette chromosome mec (SCCmec)-SCC-SCCCRISPR composite element in Irish hospitals.

    LENUS (Irish Health Repository)

    Kinnevey, Peter M

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has been a major cause of nosocomial infection in Irish hospitals for 4 decades, and replacement of predominant MRSA clones has occurred several times. An MRSA isolate recovered in 2006 as part of a larger study of sporadic MRSA exhibited a rare spa (t878) and multilocus sequence (ST779) type and was nontypeable by PCR- and DNA microarray-based staphylococcal cassette chromosome mec (SCCmec) element typing. Whole-genome sequencing revealed the presence of a novel 51-kb composite island (CI) element with three distinct domains, each flanked by direct repeat and inverted repeat sequences, including (i) a pseudo SCCmec element (16.3 kb) carrying mecA with a novel mec class region, a fusidic acid resistance gene (fusC), and two copper resistance genes (copB and copC) but lacking ccr genes; (ii) an SCC element (17.5 kb) carrying a novel ccrAB4 allele; and (iii) an SCC element (17.4 kb) carrying a novel ccrC allele and a clustered regularly interspaced short palindromic repeat (CRISPR) region. The novel CI was subsequently identified by PCR in an additional 13 t878\\/ST779 MRSA isolates, six from bloodstream infections, recovered between 2006 and 2011 in 11 hospitals. Analysis of open reading frames (ORFs) carried by the CI showed amino acid sequence similarity of 44 to 100% to ORFs from S. aureus and coagulase-negative staphylococci (CoNS). These findings provide further evidence of genetic transfer between S. aureus and CoNS and show how this contributes to the emergence of novel SCCmec elements and MRSA strains. Ongoing surveillance of this MRSA strain is warranted and will require updating of currently used SCCmec typing methods.

  6. Staphylococcal SCCmec elements encode an active MCM-like helicase and thus may be replicative

    Energy Technology Data Exchange (ETDEWEB)

    Mir-Sanchis, Ignacio; Roman, Christina A.; Misiura, Agnieszka; Pigli, Ying Z.; Boyle-Vavra, Susan; Rice , Phoebe A. (UC)

    2016-08-29

    Methicillin-resistant Staphylococcus aureus (MRSA) is a public-health threat worldwide. Although the mobile genomic island responsible for this phenotype, staphylococcal cassette chromosome (SCC), has been thought to be nonreplicative, we predicted DNA-replication-related functions for some of the conserved proteins encoded by SCC. We show that one of these, Cch, is homologous to the self-loading initiator helicases of an unrelated family of genomic islands, that it is an active 3'-to-5' helicase and that the adjacent ORF encodes a single-stranded DNA–binding protein. Our 2.9-Å crystal structure of intact Cch shows that it forms a hexameric ring. Cch, like the archaeal and eukaryotic MCM-family replicative helicases, belongs to the pre–sensor II insert clade of AAA+ ATPases. Additionally, we found that SCC elements are part of a broader family of mobile elements, all of which encode a replication initiator upstream of their recombinases. Replication after excision would enhance the efficiency of horizontal gene transfer.

  7. Transcription and translation products of the cytolysin gene psm-mec on the mobile genetic element SCCmec regulate Staphylococcus aureus virulence.

    Directory of Open Access Journals (Sweden)

    Chikara Kaito

    Full Text Available The F region downstream of the mecI gene in the SCCmec element in hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA contains two bidirectionally overlapping open reading frames (ORFs, the fudoh ORF and the psm-mec ORF. The psm-mec ORF encodes a cytolysin, phenol-soluble modulin (PSM-mec. Transformation of the F region into the Newman strain, which is a methicillin-sensitive S. aureus (MSSA strain, or into the MW2 (USA400 and FRP3757 (USA300 strains, which are community-acquired MRSA (CA-MRSA strains that lack the F region, attenuated their virulence in a mouse systemic infection model. Introducing the F region to these strains suppressed colony-spreading activity and PSMα production, and promoted biofilm formation. By producing mutations into the psm-mec ORF, we revealed that (i both the transcription and translation products of the psm-mec ORF suppressed colony-spreading activity and promoted biofilm formation; and (ii the transcription product of the psm-mec ORF, but not its translation product, decreased PSMα production. These findings suggest that both the psm-mec transcript, acting as a regulatory RNA, and the PSM-mec protein encoded by the gene on the mobile genetic element SCCmec regulate the virulence of Staphylococcus aureus.

  8. SCCmec Type IX Element in Methicillin Resistant Staphylococcusaureusspa Type t337 (CC9) Isolated from Pigs and Pork in Thailand

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Cavaco, Lina M; Sirichote, Pantip

    2012-01-01

    blaZ, aac-aphD, vga(A), tetM, and a tet efflux marker, in all strains and additionally ermB and aadD, cat and fex(A) in the pork isolates. None of the isolates were found PVL-positive, but enterotoxins were identified in all isolates. To our knowledge, only a few descriptions of MRSA in livestock...... and food products in Thailand have been observed but this is the first observation of MRSA CC9 associated with SCCmec IX in pork. This study indicates a likely widespread distribution of MRSA in pig and pork in Thailand and further investigation on the prevalence and importance of livestock associated MRSA...

  9. A new multiplex PCR for easy screening of methicillin-resistant Staphylococcus aureus SCCmec types I-V

    DEFF Research Database (Denmark)

    Boye, Kit; Bartels, Mette Damkjær; Andersen, Ina S

    2007-01-01

    A multiplex PCR with four primer-pairs was designed to identify the five main known SCCmec types. A clear and easily discriminated band pattern was obtained for all five types. The SCCmec type was identified for 98% of 312 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA......). SCCmec type IV was by far the most common SCCmec type among both hospital- and community-acquired MRSA isolates in Denmark....

  10. SCCmec type IX element in Methicillin resistant Staphylococcus aureus spa-type t337 (CC9 isolated from pigs and pork in Thailand

    Directory of Open Access Journals (Sweden)

    Martin eVestergaard

    2012-03-01

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA have emerged among livestock in several countries. In this study, we describe the results of a screening performed in pigs and raw pork samples in Thailand. Ten pork samples and 15 nasal swabs from pigs were collected from two markets and one pig farm in the Samuth Songkhram province in Thailand. MRSA were isolated using selective isolation procedures and confirmed by mecA PCR. The MRSA were characterized by antimicrobial susceptibility testing, PFGE, spa typing, SCCmec typing, and MLST. Resistance and virulence markers were screened using a microarray. Five of the pork samples and six pig nasal swabs were positive for MRSA. All 11 isolates belonged to spa type t337 and CC9 but showed diversity in antimicrobial resistance patterns and PFGE profiles. All isolates harbored SCCmec IX and were resistant to seven out of 14 tested antimicrobials; additional resistances were found in the pork isolates. Microarray analysis identified blaZ, aac-aphD, vga(A, tetM, and a tet efflux marker, in all strains and additionally ermB and aadD, cat and fex(A in the pork isolates. None of the isolates were found PVL-positive, but enterotoxins were identified in all isolates. This is, to our knowledge, the first description of MRSA in livestock and food products in Thailand and also the first observation of MRSA CC9 associated with SCCmec IX. This study indicates a likely widespread distribution of MRSA in pig and pork in Thailand and further investigation on the prevalence and importance of livestock associated MRSA in Thailand is needed.

  11. SCCmecFinder, a Web-Based Tool for Typing of Staphylococcal Cassette Chromosome mec in Staphylococcus aureus Using Whole-Genome Sequence Data

    DEFF Research Database (Denmark)

    Kaya, Hülya; Hasman, Henrik; Larsen, Jesper

    2018-01-01

    Typing of methicillin-resistant Staphylococcus aureus (MRSA) is important in infection control and surveillance. The current nomenclature of MRSA includes the genetic background of the S. aureus strain determined by multilocus sequence typing (MLST) or equivalent methods like spa typing and typing...... of the genetic background and SCCmec, but so far, no bioinformatic tools for SCCmec typing have been available. Here, we report the development and evaluation of SCCmecFinder for characterization of the SCCmec element from S. aureus WGS data. SCCmecFinder is able to identify all SCCmec element types, designated...... a diverse collection of clinical isolates (n = 93) showed a high typeability level of 96.7%, which increased to 98.9% upon modification of the default settings. In conclusion, SCCmecFinder can be an alternative to more laborious SCCmec typing methods and is freely available at https...

  12. A new multiplex PCR for easy screening of methicillin-resistant Staphylococcus aureus SCCmec types I-V

    DEFF Research Database (Denmark)

    Boye, Kit; Bartels, Mette Damkjær; Andersen, Ina S

    2007-01-01

    A multiplex PCR with four primer-pairs was designed to identify the five main known SCCmec types. A clear and easily discriminated band pattern was obtained for all five types. The SCCmec type was identified for 98% of 312 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA...

  13. Distribution of SCCmec-associated phenol-soluble modulin in staphylococci.

    LENUS (Irish Health Repository)

    Monecke, Stefan

    2012-04-01

    The recently described phenol-soluble modulin PSM-mec was detected in Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus fleuretti, Staphylococcus hominis, Staphylococcus pseudintermedius, Staphylococcus saprophyticus, Staphylococcus simulans and Staphylococcus vitulinus from different hosts (humans, goats, dogs, cats, pigs, cattle and turkeys). It was identified in isolates harbouring SCCmec types II, IIA, IIB, IID, III, VIII and in some irregular or truncated elements.

  14. DNA microarray profiling of a diverse collection of nosocomial methicillin-resistant staphylococcus aureus isolates assigns the majority to the correct sequence type and staphylococcal cassette chromosome mec (SCCmec) type and results in the subsequent identification and characterization of novel SCCmec-SCCM1 composite islands.

    LENUS (Irish Health Repository)

    Shore, Anna C

    2012-10-01

    One hundred seventy-five isolates representative of methicillin-resistant Staphylococcus aureus (MRSA) clones that predominated in Irish hospitals between 1971 and 2004 and that previously underwent multilocus sequence typing (MLST) and staphylococcal cassette chromosome mec (SCCmec) typing were characterized by spa typing (175 isolates) and DNA microarray profiling (107 isolates). The isolates belonged to 26 sequence type (ST)-SCCmec types and subtypes and 35 spa types. The array assigned all isolates to the correct MLST clonal complex (CC), and 94% (100\\/107) were assigned an ST, with 98% (98\\/100) correlating with MLST. The array assigned all isolates to the correct SCCmec type, but subtyping of only some SCCmec elements was possible. Additional SCCmec\\/SCC genes or DNA sequence variation not detected by SCCmec typing was detected by array profiling, including the SCC-fusidic acid resistance determinant Q6GD50\\/fusC. Novel SCCmec\\/SCC composite islands (CIs) were detected among CC8 isolates and comprised SCCmec IIA-IIE, IVE, IVF, or IVg and a ccrAB4-SCC element with 99% DNA sequence identity to SCC(M1) from ST8\\/t024-MRSA, SCCmec VIII, and SCC-CI in Staphylococcus epidermidis. The array showed that the majority of isolates harbored one or more superantigen (94%; 100\\/107) and immune evasion cluster (91%; 97\\/107) genes. Apart from fusidic acid and trimethoprim resistance, the correlation between isolate antimicrobial resistance phenotype and the presence of specific resistance genes was ≥97%. Array profiling allowed high-throughput, accurate assignment of MRSA to CCs\\/STs and SCCmec types and provided further evidence of the diversity of SCCmec\\/SCC. In most cases, array profiling can accurately predict the resistance phenotype of an isolate.

  15. Associations between dru Types and SCCmec Cassettes

    DEFF Research Database (Denmark)

    Bartels, Mette D; Boye, Kit; Oliveira, Duarte C

    2013-01-01

    SCCmec types I to VI. The isolates represented a broad genetic background based on Staphylococcal protein A (spa) typing and multilocus sequence typing (MLST) and included 68 isolates (68 patients) from an outbreak with t024-ST8-IVa and 26 isolates from the same patient. Sequencing identified 53 dru......Molecular typing is an important tool in the investigation of methicillin resistant Staphylococcus aureus (MRSA) outbreaks and in following the evolution of MRSA. The staphylococcal cassette chromosome mec (SCCmec) contains a hypervariable region with a variable number of 40 bp repeats named direct...... repeat units (dru). The dru region has been suggested as a supplementary typing method for MRSA and an international nomenclature exists. The purpose of this study was to investigate the diversity and variability of the dru region in a diverse collection of MRSA. We studied 302 MRSA isolates harbouring...

  16. Predominant Dissemination of PVL-Negative CC89 MRSA with SCCmec Type II in Children with Impetigo in Japan

    Directory of Open Access Journals (Sweden)

    H. Kikuta

    2011-01-01

    Full Text Available Background. The ratio of CA-MRSA in children with impetigo has been increasing in Japan. Methods. Antimicrobial susceptibilities of 136 S. aureus isolates from children with impetigo were studied. Furthermore, molecular epidemiological analysis and virulence gene analysis were performed. Results. Of the 136 S. aureus isolates, 122 (89.7% were MSSA and 14 (10.3% were MRSA. Of the 14 MRSA strains, 11 belonged to CC89 (ST89, ST91, and ST2117 and carried diverse types of SCCmec: type II (IIb: 3 strains; unknown subtype: 4 strains, type IVa (2 strains, and unknown type (2 strains. The remaining three strains exhibited CC8 (ST-8-SCCmec type VIa, CC121 (ST121-SCCmec type V, and CC5 (ST5-nontypeable SCCmec element, respectively. None were lukS-PV-lukF-PV gene positive. Gentamicin- and clarithromycin-resistant strains were frequently found in both MRSA and MSSA. Conclusions. PVL-negative CC89-SCCmec type II strains are the most predominant strains among the CA-MRSA strains circulating in the community in Japan.

  17. CC8 MRSA strains harboring SCCmec type IVc are predominant in Colombian hospitals.

    Directory of Open Access Journals (Sweden)

    J Natalia Jiménez

    Full Text Available BACKGROUND: Recent reports highlight the incursion of community-associated MRSA within healthcare settings. However, knowledge of this phenomenon remains limited in Latin America. The aim of this study was to evaluate the molecular epidemiology of MRSA in three tertiary-care hospitals in Medellín, Colombia. METHODS: An observational cross-sectional study was conducted from 2008-2010. MRSA infections were classified as either community-associated (CA-MRSA or healthcare-associated (HA-MRSA, with HA-MRSA further classified as hospital-onset (HAHO-MRSA or community-onset (HACO-MRSA according to standard epidemiological definitions established by the U.S. Centers for Disease Control and Prevention (CDC. Genotypic analysis included SCCmec typing, spa typing, PFGE and MLST. RESULTS: Out of 538 total MRSA isolates, 68 (12.6% were defined as CA-MRSA, 243 (45.2% as HACO-MRSA and 227 (42.2% as HAHO-MRSA. The majority harbored SCCmec type IVc (306, 58.7%, followed by SCCmec type I (174, 33.4%. The prevalence of type IVc among CA-, HACO- and HAHO-MRSA isolates was 92.4%, 65.1% and 43.6%, respectively. From 2008 to 2010, the prevalence of type IVc-bearing strains increased significantly, from 50.0% to 68.2% (p = 0.004. Strains harboring SCCmec IVc were mainly associated with spa types t1610, t008 and t024 (MLST clonal complex 8, while PFGE confirmed that the t008 and t1610 strains were closely related to the USA300-0114 CA-MRSA clone. Notably, strains belonging to these three spa types exhibited high levels of tetracycline resistance (45.9%. CONCLUSION: CC8 MRSA strains harboring SCCmec type IVc are becoming predominant in Medellín hospitals, displacing previously reported CC5 HA-MRSA clones. Based on shared characteristics including SCCmec IVc, absence of the ACME element and tetracycline resistance, the USA300-related isolates in this study are most likely related to USA300-LV, the recently-described 'Latin American variant' of USA300.

  18. Disperse reinforced concrete used in obtaining prefabricated elements for roads

    Directory of Open Access Journals (Sweden)

    Bogdan MEZEI

    2014-07-01

    Full Text Available Concrete is the most used material in construction. By improving the performance of materials and of technologies, concretes with outstanding performances were also developed, in the past two decades. Concrete with dispersed reinforcement represents a new generation of reinforced concrete that combines a good behavior of concrete compressive strength with an increased tensile strength of steel fibers. Using this material, monolithic and prefabricated concrete elements with high mechanical strengths and high durability can be obtained. Technological processes for preparation of concrete with dispersed reinforcement are similar to the conventional methods and do not involve using additional equipment for dosing the dispersed reinforcement. The study aimed the development of road plates made with optimized disperse- reinforced concrete. The first tests were done on plates from the gutter roadway, having a classic reinforcement, using different percentages of fibre reinforcement in the concrete composition, leading to the development of a new optimized economical solution. The results prove the enhanced characteristics of the disperse-reinforced concrete versus conventional concrete, and hence of the developed concrete plates.

  19. A code for obtaining temperature distribution by finite element method

    International Nuclear Information System (INIS)

    Bloch, M.

    1984-01-01

    The ELEFIB Fortran language computer code using finite element method for calculating temperature distribution of linear and two dimensional problems, in permanent region or in the transient phase of heat transfer, is presented. The formulation of equations uses the Galerkin method. Some examples are shown and the results are compared with other papers. The comparative evaluation shows that the elaborated code gives good values. (M.C.K.) [pt

  20. Obtaining local reciprocal lattice vectors from finite-element analysis.

    Science.gov (United States)

    Sutter, John P; Connolley, Thomas; Hill, Tim P; Huang, Houcheng; Sharp, Doug W; Drakopoulos, Michael

    2008-11-01

    Finite-element analysis is frequently used by engineers at synchrotron beamlines to calculate the elastic deformation of a single crystal undergoing mechanical bending or thermal load. ANSYS Workbench software is widely used for such simulations. However, although ANSYS Workbench software provides useful information on the displacements, strains and stresses within the crystal, it does not yield the local reciprocal lattice vectors that would be required for X-ray diffraction calculations. To bridge this gap, a method based on the shape functions and interpolation procedures of the software itself has been developed. An application to the double-crystal bent Laue monochromator being designed for the I12 (JEEP) wiggler beamline at the Diamond Light Source is presented.

  1. Comparative Genotypes, Staphylococcal Cassette Chromosome mec (SCCmec) Genes and Antimicrobial Resistance amongst Staphylococcus epidermidis and Staphylococcus haemolyticus Isolates from Infections in Humans and Companion Animals.

    Science.gov (United States)

    McManus, Brenda A; Coleman, David C; Deasy, Emily C; Brennan, Gráinne I; O' Connell, Brian; Monecke, Stefan; Ehricht, Ralf; Leggett, Bernadette; Leonard, Nola; Shore, Anna C

    2015-01-01

    This study compares the characteristics of Staphylococcus epidermidis (SE) and Staphylococcus haemolyticus (SH) isolates from epidemiologically unrelated infections in humans (Hu) (28 SE-Hu; 8 SH-Hu) and companion animals (CpA) (12 SE-CpA; 13 SH-CpA). All isolates underwent antimicrobial susceptibility testing, multilocus sequence typing and DNA microarray profiling to detect antimicrobial resistance and SCCmec-associated genes. All methicillin-resistant (MR) isolates (33/40 SE, 20/21 SH) underwent dru and mecA allele typing. Isolates were predominantly assigned to sequence types (STs) within a single clonal complex (CC2, SE, 84.8%; CC1, SH, 95.2%). SCCmec IV predominated among MRSE with ST2-MRSE-IVc common to both Hu (40.9%) and CpA (54.5%). Identical mecA alleles and nontypeable dru types (dts) were identified in one ST2-MRSE-IVc Hu and CpA isolate, however, all mecA alleles and 2/4 dts detected among 18 ST2-MRSE-IVc isolates were closely related, sharing >96.5% DNA sequence homology. Although only one ST-SCCmec type combination (ST1 with a non-typeable [NT] SCCmec NT9 [class C mec and ccrB4]) was common to four MRSH-Hu and one MRSH-CpA, all MRSH isolates were closely related based on similar STs, SCCmec genes (V/VT or components thereof), mecA alleles and dts. Overall, 39.6% of MR isolates harbored NT SCCmec elements, and ACME was more common amongst MRSE and CpA isolates. Multidrug resistance (MDR) was detected among 96.7% of isolates but they differed in the prevalence of specific macrolide, aminoglycoside and trimethoprim resistance genes amongst SE and SH isolates. Ciprofloxacin, rifampicin, chloramphenicol [fexA, cat-pC221], tetracycline [tet(K)], aminoglycosides [aadD, aphA3] and fusidic acid [fusB] resistance was significantly more common amongst CpA isolates. SE and SH isolates causing infections in Hu and CpA hosts belong predominantly to STs within a single lineage, harboring similar but variable SCCmec genes, mecA alleles and dts. Host and

  2. Comparative Genotypes, Staphylococcal Cassette Chromosome mec (SCCmec Genes and Antimicrobial Resistance amongst Staphylococcus epidermidis and Staphylococcus haemolyticus Isolates from Infections in Humans and Companion Animals.

    Directory of Open Access Journals (Sweden)

    Brenda A McManus

    Full Text Available This study compares the characteristics of Staphylococcus epidermidis (SE and Staphylococcus haemolyticus (SH isolates from epidemiologically unrelated infections in humans (Hu (28 SE-Hu; 8 SH-Hu and companion animals (CpA (12 SE-CpA; 13 SH-CpA. All isolates underwent antimicrobial susceptibility testing, multilocus sequence typing and DNA microarray profiling to detect antimicrobial resistance and SCCmec-associated genes. All methicillin-resistant (MR isolates (33/40 SE, 20/21 SH underwent dru and mecA allele typing. Isolates were predominantly assigned to sequence types (STs within a single clonal complex (CC2, SE, 84.8%; CC1, SH, 95.2%. SCCmec IV predominated among MRSE with ST2-MRSE-IVc common to both Hu (40.9% and CpA (54.5%. Identical mecA alleles and nontypeable dru types (dts were identified in one ST2-MRSE-IVc Hu and CpA isolate, however, all mecA alleles and 2/4 dts detected among 18 ST2-MRSE-IVc isolates were closely related, sharing >96.5% DNA sequence homology. Although only one ST-SCCmec type combination (ST1 with a non-typeable [NT] SCCmec NT9 [class C mec and ccrB4] was common to four MRSH-Hu and one MRSH-CpA, all MRSH isolates were closely related based on similar STs, SCCmec genes (V/VT or components thereof, mecA alleles and dts. Overall, 39.6% of MR isolates harbored NT SCCmec elements, and ACME was more common amongst MRSE and CpA isolates. Multidrug resistance (MDR was detected among 96.7% of isolates but they differed in the prevalence of specific macrolide, aminoglycoside and trimethoprim resistance genes amongst SE and SH isolates. Ciprofloxacin, rifampicin, chloramphenicol [fexA, cat-pC221], tetracycline [tet(K], aminoglycosides [aadD, aphA3] and fusidic acid [fusB] resistance was significantly more common amongst CpA isolates. SE and SH isolates causing infections in Hu and CpA hosts belong predominantly to STs within a single lineage, harboring similar but variable SCCmec genes, mecA alleles and dts. Host and

  3. Quality and Trace Element Profile of Tunisian Olive Oils Obtained from Plants Irrigated with Treated Wastewater

    Directory of Open Access Journals (Sweden)

    Cinzia Benincasa

    2012-01-01

    Full Text Available In the present work the use of treated wastewater (TWW to irrigate olive plants was monitored. This type of water is characterized by high salinity and retains a substantial amount of trace elements, organic and metallic compounds that can be transferred into the soil and into the plants and fruits. In order to evaluate the impact of TWW on the overall quality of the oils, the time of contact of the olives with the soil has been taken into account. Multi-element data were obtained using ICP-MS. Nineteen elements (Li, B, Na, Mg, Al, K, Ca, Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Mo, Ba and La were submitted for statistical analysis. Using analysis of variance, linear discriminant analysis and principal component analysis it was possible to differentiate between oils produced from different batches of olives whose plants received different types of water. Also, the results showed that there was correlation between the elemental and mineral composition of the water used to irrigate the olive plots and the elemental and mineral composition of the oils.

  4. Obtaining Approximate Values of Exterior Orientation Elements of Multi-Intersection Images Using Particle Swarm Optimization

    Science.gov (United States)

    Li, X.; Li, S. W.

    2012-07-01

    In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO), is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm, two experiments are

  5. OBTAINING APPROXIMATE VALUES OF EXTERIOR ORIENTATION ELEMENTS OF MULTI-INTERSECTION IMAGES USING PARTICLE SWARM OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    X. Li

    2012-07-01

    Full Text Available In this paper, an efficient global optimization algorithm in the field of artificial intelligence, named Particle Swarm Optimization (PSO, is introduced into close range photogrammetric data processing. PSO can be applied to obtain the approximate values of exterior orientation elements under the condition that multi-intersection photography and a small portable plane control frame are used. PSO, put forward by an American social psychologist J. Kennedy and an electrical engineer R.C. Eberhart, is a stochastic global optimization method based on swarm intelligence, which was inspired by social behavior of bird flocking or fish schooling. The strategy of obtaining the approximate values of exterior orientation elements using PSO is as follows: in terms of image coordinate observed values and space coordinates of few control points, the equations of calculating the image coordinate residual errors can be given. The sum of absolute value of each image coordinate is minimized to be the objective function. The difference between image coordinate observed value and the image coordinate computed through collinear condition equation is defined as the image coordinate residual error. Firstly a gross area of exterior orientation elements is given, and then the adjustment of other parameters is made to get the particles fly in the gross area. After iterative computation for certain times, the satisfied approximate values of exterior orientation elements are obtained. By doing so, the procedures like positioning and measuring space control points in close range photogrammetry can be avoided. Obviously, this method can improve the surveying efficiency greatly and at the same time can decrease the surveying cost. And during such a process, only one small portable control frame with a couple of control points is employed, and there are no strict requirements for the space distribution of control points. In order to verify the effectiveness of this algorithm

  6. Novel types of staphylococcal cassette chromosome mec elements identified in clonal complex 398 methicillin-resistant Staphylococcus aureus strains.

    NARCIS (Netherlands)

    Li, S.; Skov, R.L.; Han, X.; Larsen, A.R.; Larsen, J.; Sorum, M.; Wulf, M.; Voss, A.; Hiramatsu, K.; Ito, T.

    2011-01-01

    The structures of staphylococcal cassette chromosome mec (SCCmec) elements carried by 31 clonal complex 398 (CC398) methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from the participants at a conference were analyzed. The SCCmecs were classified into novel types, namely, IX, X,

  7. Sequence Capture and Phylogenetic Utility of Genomic Ultraconserved Elements Obtained from Pinned Insect Specimens.

    Directory of Open Access Journals (Sweden)

    Bonnie B Blaimer

    Full Text Available Obtaining sequence data from historical museum specimens has been a growing research interest, invigorated by next-generation sequencing methods that allow inputs of highly degraded DNA. We applied a target enrichment and next-generation sequencing protocol to generate ultraconserved elements (UCEs from 51 large carpenter bee specimens (genus Xylocopa, representing 25 species with specimen ages ranging from 2-121 years. We measured the correlation between specimen age and DNA yield (pre- and post-library preparation DNA concentration and several UCE sequence capture statistics (raw read count, UCE reads on target, UCE mean contig length and UCE locus count with linear regression models. We performed piecewise regression to test for specific breakpoints in the relationship of specimen age and DNA yield and sequence capture variables. Additionally, we compared UCE data from newer and older specimens of the same species and reconstructed their phylogeny in order to confirm the validity of our data. We recovered 6-972 UCE loci from samples with pre-library DNA concentrations ranging from 0.06-9.8 ng/μL. All investigated DNA yield and sequence capture variables were significantly but only moderately negatively correlated with specimen age. Specimens of age 20 years or less had significantly higher pre- and post-library concentrations, UCE contig lengths, and locus counts compared to specimens older than 20 years. We found breakpoints in our data indicating a decrease of the initial detrimental effect of specimen age on pre- and post-library DNA concentration and UCE contig length starting around 21-39 years after preservation. Our phylogenetic results confirmed the integrity of our data, giving preliminary insights into relationships within Xylocopa. We consider the effect of additional factors not measured in this study on our age-related sequence capture results, such as DNA fragmentation and preservation method, and discuss the promise of the UCE

  8. Correlation analysis of trace elemental data obtained from blood sera of ovarian cancer patients using PIXE

    International Nuclear Information System (INIS)

    Naidu, B.G.; Sarita, P.; Naga Raju, G.J.

    2017-01-01

    Proton induced X-ray emission (PIXE) technique is used for analysis of trace elements present in the blood sera of ovarian cancer patients and healthy controls. This work is also intended to establish the role played by trace elements in carcinogenic process. It is observed that the concentrations of elements Ti, V, Cr, Mn, Fe, Ni, Rb and Sr are lower and the concentration of Cu is higher in the cancer patients when compared to controls. However, no change in concentration is found in the elements Co, Zn, As, Se and Br. Correlation analysis of the data using SPSS 16.0 has revealed a strong positive correlation between Ti-V, Ni-Co, Cu-Fe, As-Ti, Br-Ti, Br-V and Sr-Fe while strong negative correlations are observed for Cu-Ti, As-Cu and Br-Cu. Changes in trace elemental content are probably associated with ovarian carcinogenesis. (author)

  9. Study of Finite Element Number Influence over the Obtained Results in Finite Element Analyses of a Mechanical Structure

    Directory of Open Access Journals (Sweden)

    Ana-Maria Budai

    2013-05-01

    Full Text Available This paper present the results of a study that was made to establish the influence of finite element number used to determined the real load of a structure. Actually, the study represent a linear static analyze for a link gear control mechanism of a Kaplan turbine. The all analyze was made for the normal condition of functioning having like final scope to determine de life time duration of mentioned mechanism.

  10. Recovery of enriched Uranium (20% U-235) from wastes obtained in the preparation of fuel elements for argonaut type reactors

    International Nuclear Information System (INIS)

    Uriarte, A.; Ramos, L.; Estrada, J.; del Val, J. L.

    1962-01-01

    Results obtained with the two following installations for recovering enriched uranium (20% U-235) from wastes obtained in the preparation of fuel elements for Argonaut type reactors are presented. Ion exchange unit to recover uranium form mother liquors resulting from the precipitation ammonium diuranate (ADU) from UO 2 F 2 solutions. Uranium recovery unit from solid wastes from the process of manufacture of fuel elements, consisting of a) waste dissolution, and b) extraction with 10% (v/v) TBP. (Author) 9 refs

  11. Whole-genome comparison of meticillin-resistant Staphylococcus aureus CC22 SCCmecIV from people and their in-contact pets.

    Science.gov (United States)

    Loeffler, Anette; McCarthy, Alex; Lloyd, David H; Musilová, Eva; Pfeiffer, Dirk U; Lindsay, Jodi A

    2013-10-01

    Meticillin-resistant Staphylococcus aureus (MRSA) infections remain important medical and veterinary challenges. The MRSA isolated from dogs and cats typically belong to dominant hospital-associated clones, in the UK mostly EMRSA-15 (CC22 SCCmecIV), suggesting original human-to-animal transmission. Nevertheless, little is known about host-specific genetic variation within the same S. aureus lineage. To identify host-specific variation amongst MRSA CC22 SCCmecIV by comparing isolates from pets with those from in-contact humans using whole-genome microarray. Six pairs of MRSA CC22 SCCmecIV from human carriers (owners and veterinary staff) and their respective infected in-contact pets were compared using a 62-strain whole-genome S. aureus microarray (SAM-62). The presence of putative host-specific genes was subsequently determined in a larger number of human (n = 47) and pet isolates (n = 93) by PCR screening. Variation in mobile genetic elements (MGEs) occurred frequently and appeared largely independent of host and in-contact pair. A plasmid (SAP078A) encoding heavy-metal resistance genes (arsR, arsA, cadA, cadC, mco and copB) was found in three of six human and none of six animal isolates. However, only two of four resistance genes were associated with human hosts (P = 0.015 for arsA and cadA). The variation found amongst MGEs highlights that genetic adaptation in MRSA continues. However, host-specific MGEs were not detected, which supports the hypothesis that pets may not be natural hosts of MRSA CC22 and emphasizes that rigorous hygiene measures are critical to prevent contamination and infection of dogs and cats. The host specificity of individual heavy-metal resistance genes warrants further investigation into different selection pressures in humans and animals. © 2013 ESVD and ACVD.

  12. Tetracycline and trimethoprim/sulfamethoxazole at clinical laboratory: can they help to characterize Staphylococcus aureus carrying different SCCmec types?

    Science.gov (United States)

    Cavalcante, Fernanda Sampaio; Schuenck, Ricardo Pinto; Caboclo, Roberta Mello Ferreira; Ferreira, Dennis de Carvalho; Nouér, Simone Aranha; Santos, Kátia Regina Netto dos

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) can be difficult to detect at the clinical practice. We analyzed 140 MRSA isolates from inpatients to correlate the antimicrobial susceptibility with the SCCmec types. Type III (n = 63) isolates were more resistant to ciprofloxacin, clindamycin, cloramphenicol, erythromycin, gentamicin, and rifampin than type IV (n = 65) ones (p < 0.05). Moreover, type IV isolates were susceptible to tetracycline (100%) and trimethoprim/sulfamethoxazole (98%), while type III isolates presented resistance to them. In regions where these SCCmec types are prevalent, the detection of specific resistant phenotypes could help to predict them, mainly when there are no technical conditions to SCCmec typing.

  13. Yttrium separation of Xenotime waste in Pitinga (Brazil), in order to obtain rare earth elements

    International Nuclear Information System (INIS)

    Melo.

    1996-01-01

    The xenotime (YPO 4 and rare earth elements) found in the mine of Pitinga, Amazonas State, Brazil, has its origin in a primal depository ('eluvio' kind) of cassiterite, having considerable quantities of zirconite, ilmenite, topaz and niobates-tantalates. This xenotime has different characteristics in relation of the depositories that exist in other countries for presenting more concentration of rare earth heavy oxides. The mineralization of this cassiterite is problematic, because of the high level of radioactive elements. In the present work, we will process only the xenotime. The separation of rare earth elements is very difficult due to their great chemical similarity. For a more exactly determination, it is necessary to separate them at least of the macron constituents of the sample. As the Yttrium is considerate one of the rare earth elements, due to its chemical similarity, we can understand the difficulty of a chemical separation, mainly when this one is also a macro constituent of the sample, as in the case of xenotime. The process of separation will be based on the little difference that exists between the constants of complexation and the fluoride. (authors). 5 refs., 1 fig., 2 tabs

  14. Recovery of enriched Uranium (20% U-235) from wastes obtained in the preparation of fuel elements for argonaut type reactors

    Energy Technology Data Exchange (ETDEWEB)

    Uriarte, A; Ramos, L; Estrada, J; Val, J L. del

    1962-07-01

    Results obtained with the two following installations for recovering enriched uranium (20% U-235) from wastes obtained in the preparation of fuel elements for Argonaut type reactors are presented. Ion exchange unit to recover uranium form mother liquors resulting from the precipitation ammonium diuranate (ADU) from UO{sub 2}F{sub 2} solutions. Uranium recovery unit from solid wastes from the process of manufacture of fuel elements, consisting of a) waste dissolution, and b) extraction with 10% (v/v) TBP. (Author) 9 refs.

  15. Information on the evolution of severe LWR fuel element damage obtained in the CORA program

    International Nuclear Information System (INIS)

    Schanz, G.; Hagen, S.; Hofmann, P.; Sepold, L.; Schumacher, G.

    1992-01-01

    In the CORA program a series of out-of-pile experiments on LWR severe accidental situations is being performed, in which test bundles of LWR typical components and arrangements (PWR, BWR) are exposed to temperature transients up to about 2400deg C under flowing steam. The individual features of the facility, the test conduct, and the evaluation will be presented. In the frame of the international cooperation in severe fuel damage (SFD) programs the CORA tests are contributing confirmatory and complementary informations to the results from the limited number of in-pile tests. The identification of basic phenomena of the fuel element destruction, observed as a function of temperature, is supported by separate-effects test results. Most important mechanisms are the steam oxidation of the Zircaloy cladding, which determines the temperature escalation, the chemical interaction between UO 2 fuel and cladding, which dominates fuel liquefaction, relocation and resulting blockage formation, as well as chemical interactions with Inconel spacer grids and absorber units ((Ag, In, Cd) alloy or B 4 C), which are leading to extensive low-temperature melt formation around 1200deg C. Interrelations between those basic phenomena, resulting for example in cladding deformation ('flowering') and the dramatic hydrogen formation in response to the fast cooling of a hot bundle by cold water ('quenching') are determining the evolution paths of fuel element destruction, which are to be identified. (orig.)

  16. Evolutionary Origin of the Staphylococcal Cassette Chromosome mec (SCCmec)

    DEFF Research Database (Denmark)

    Rolo, Joana; Worning, Peder; Nielsen, Jesper Boye

    2017-01-01

    , many steps are still missing from this evolutionary history. In particular, it is not known how mecA was incorporated into the mobile element SCC prior to dissemination among Staphylococcus aureus and other pathogenic staphylococcal species. To gain insights into the possible contribution of several...

  17. The dissemination of ST80-SCCmec-IV community-associated methicillin resistant Staphylococcus aureus clone in Kuwait hospitals

    Directory of Open Access Journals (Sweden)

    Sarkhoo Eiman

    2010-11-01

    Full Text Available Abstract Background Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA is a global healthcare problem. The purpose of this study was to characterize CA-MRSA clones and their distribution in Kuwait hospitals. Methods In total, 135 CA-MRSA isolates, carrying the SCCmec IV or V genetic elements, isolated in eight hospitals were characterized using antibiogram, pulsed-field gel electrophoresis, multilocus sequence typing, and carriage of genes for Panton-Valentine Leukocidin (PVL, capsular polysaccharides types (cap 5 and 8, accessory genes regulators (agr, Staphylococcal enterotoxins (SE and toxic shock syndrome toxin 1 (tst. Results They were susceptible to vancomycin, teicoplanin and linezolid but resistant to kanamycin (62%, fusidic acid (42.2%, tetracycline (39.3%, erythromycin and clindamycin (21.5%, gentamicin (5.9%, streptomycin (6.7%, trimethoprim (5.9%, mupirocin (6.6% and cadmium acetate (82.2%. They consisted of 10 pulsotypes with the majority belonging to PFGE type I (51.1%, type II (22.2%, type IV (13.3% and type III (3.7%. They belonged to 10 sequence types (ST comprising ST80 (51.1%, ST30 (22.2%, ST5 (14.1%, ST1 (4.45, ST6 (3.7%, ST88 (1.5%, ST834 (1.5%, ST8 (0.7%, ST46 (0.7% and ST950 (0.7%. Genes for PVL, cap 8, cap 5 and agr III, agr I and agr II were detected in 61.5%, 77.3%, 20.7% and 62.2%, 17% and 8.1% of the isolates respectively. Nine (6.7% isolates contained tst while 103 isolates were positive for SE genes with sei (63.0%, seg (41.5% and sed (29.6% as the common SE genes. Conclusions ST80-SCCmecIV was the most common CA-MRSA clone in Kuwait hospitals presenting new challenges for infection control.

  18. An Unexpected Location of the Arginine Catabolic Mobile Element (ACME) in a USA300-Related MRSA Strain

    DEFF Research Database (Denmark)

    Damkjær Bartels, Mette; Hansen, Lars H.; Boye, Kit

    2011-01-01

    In methicillin resistant Staphylococcus aureus (MRSA), the arginine catabolic mobile element (ACME) was initially described in USA300 (t008-ST8) where it is located downstream of the staphylococcal cassette chromosome mec (SCCmec). A common health-care associated MRSA in Copenhagen, Denmark (t024......-ST8) is clonally related to USA300 and is frequently PCR positive for the ACME specific arcA-gene. This study is the first to describe an ACME element upstream of the SCCmec in MRSA. By traditional SCCmec typing schemes, the SCCmec of t024-ST8 strain M1 carries SCCmec IVa, but full sequencing...... of SCCmec, M1 had two new DR between the orfX gene and the J3 region of the SCCmec. The region between the orfX DR (DR1) and DR2 contained the ccrAB4 genes. An ACME II-like element was located between DR2 and DR3. The entire 26,468 bp sequence between DR1 and DR3 was highly similar to parts of the ACME...

  19. Influence of the crack propagation rate in the obtaining opening and closing stress intensity factor by finite element method

    OpenAIRE

    Luiz Carlos H. Ricardo; Carlos Alexandre J. Miranda

    2016-01-01

    Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth. Today structural and materials engineers develop structures and materials properties using this technique as criterion design. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading fr...

  20. Leaching of Major and Minor Elements during the Transport and Storage of Coal Ash Obtained in Power Plant

    Directory of Open Access Journals (Sweden)

    Rada Krgović

    2014-01-01

    Full Text Available In power plant, coal ash obtained by combustion is mixed with river water and transported to the dump. Sequential extraction was used in order to assess pollution caused by leaching of elements during ash transport through the pipeline and in the storage (cassettes. A total of 80 samples of filter ash as well as the ash from active (currently filled and passive (previously filled cassettes were studied. Samples were extracted with distilled water, ammonium acetate, ammonium oxalate/oxalic acid, acidic solution of hydrogen-peroxide, and a hydrochloric acid. Concentrations of the several elements (Al, As, Cd, Co, Cu, Cr, Fe, Ba, Ca, Mg, Ni, Pb, and Zn in all extracts were determined by inductively coupled plasma atomic emission spectrometry. Pattern recognition method was carried out in order to provide better understanding of the nature of distribution of elements according to their origins. Results indicate possible leaching of As, Ca, Cd, Cu, Zn, and Pb. Among these elements As, Cd, and Pb are toxicologically the most important but they were not present in the first two phases with the exception of As. The leaching could be destructive and cause negative effects on plants, water pollution, and damage to some life forms.

  1. Examination and Improvement of Accuracy of Three-Dimensional Elastic Crack Solutions Obtained Using Finite Element Alternating Method

    International Nuclear Information System (INIS)

    Park, Jai Hak; Nikishkov, G. P.

    2010-01-01

    An SGBEM (symmetric Galerkin boundary element method)-FEM alternating method has been proposed by Nikishkov, Park and Atluri. This method can be used to obtain mixed-mode stress intensity factors for planar and nonplanar three-dimensional cracks having an arbitrary shape. For field applications, however, it is necessary to verify the accuracy and consistency of this method. Therefore, in this study, we investigate the effects of several factors on the accuracy of the stress intensity factors obtained using the above mentioned alternating method. The obtained stress intensity factors are compared with the known values provided in handbooks, especially in the case of internal and external circumferential semi-elliptical surface cracks. The results show that the SGBEM-FEM alternating method yields accurate stress intensity factors for three-dimensional cracks, including internal and external circumferential surface cracks and that the method can be used as a robust crack analysis tool for solving field problems

  2. Influence of the crack propagation rate in the obtaining opening and closing stress intensity factor by finite element method

    Directory of Open Access Journals (Sweden)

    Luiz Carlos H. Ricardo

    2016-03-01

    Full Text Available Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth. Today structural and materials engineers develop structures and materials properties using this technique as criterion design. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Keyhole Specimen Test Load Histories by finite element analysis. The crack propagation simulation was based on release nodes at the minimum loads to minimize convergence problems. To understand the crack propagation processes under variable amplitude loading, retardation effects are discussed.

  3. Elemental concentration variations in Plio-Pleistocene sediments from ODP Site 1143 (southern South China Sea) obtained by XRF analyses

    Science.gov (United States)

    Tian, J.; Xie, X.; Jin, H.; Wang, P.; Jian, Z.

    2009-12-01

    Energy dispersive X-ray fluorescence (XRF) scanning technology provides the most accurate and most economic analytical methods for the determination of major and minor elements of the deep-sea sediment ranging from sodium (11) to uranium (92). Scanning on the smooth core surface by XRF Core scanner is reliable and non-destructive to the sediment, requiring little or no time to prepare the core. This method overcomes the drawback of the traditional analytical method by ICP-AES or ICP-MS which requires long time for sample preparation. Thus, it makes it viable to reconstruct long and high-resolution elemental time series from sediment cores. We have performed relatively elemental concentration analyses on the deep sea sediment cores from ODP site 1143 (southern SCS) down to 190.77 mcd (meters composite depth) by XRF core scanner. The depth resolution of the scanning is 1 cm, equivalent to a time resolution of ~250 years. The age model is based on tuning the benthic foraminiferal d18O at Site 1143 to obliquity and precession (Tian et al., 2002) which indicates that the 190.77 meters long sediment spans the past 5 Myr. We compared the records between 99.5 and 136.46 mcd with the elemental records from the same site obtained by Philips PW 2400 X-ray spectrometer (Wehausen et al., online publication). Comparison reveals, regardless of the absolute changes of the elements, that the elemental records (Si, Ti, Al, Fe, Mn, Ca, K, P, Ba, Rb, Sr) obtained by two methods are nearly the same. Results show that the relative concentration variations of the productivity related elements such as Ba and Ca display distinctive glacial-interglacial cycles for the past 5 Myr. These productivity cycles recorded show one-on-one relationship with the glacial-interglacial cycles of the global ice volume change recorded in the benthic foraminiferal d18O. The glacial-interglacial cycles in productivity and global ice volume changes are consistent with each other not only in amplitude but also

  4. 3D reconstruction of bony elements of the knee joint and finite element analysis of total knee prosthesis obtained from the reconstructed model.

    Science.gov (United States)

    Djoudi, Farid

    2013-01-01

    Two separate themes are presented in this paper. The first theme is to present a graphical modeling approach of human anatomical structures namely, the femur and the tibia. The second theme involves making a finite element analysis of stresses, displacements and deformations in prosthetic implants (the femoral implant and the polyethylene insert). The graphical modeling approach comes in two parts. The first is the segmentation of MRI scanned images, retrieved in DICOM format for edge detection. In the second part, 3D-CAD models are generated from the results of the segmentation stage. The finite element analysis is done by first extracting the prosthetic implants from the reconstructed 3D-CAD model, then do a finite element analysis of these implants under objectively determined conditions such as; forces, allowed displacements, the materials composing implant, and the coefficient of friction. The objective of this work is to implement an interface for exchanging data between 2D MRI images obtained from a medical diagnosis of a patient and the 3D-CAD model used in various applications, such as; the extraction of the implants, stress analysis at the knee joint and can serve as an aid to surgery, also predict the behavior of the prosthetic implants vis-a-vis the forces acting on the knee joints.

  5. Investigation of Vermiwash Obtained from California Red Worm Which Fed Cow Dung in terms of Trace and Nutrient Elements

    Directory of Open Access Journals (Sweden)

    Turan Yüksek

    2017-08-01

    Full Text Available One of the most important problems facing sustainable agriculture is the supply of quality fertilizers and the problems encountered in the application of fertilizers. In the last years, while trying to increase the amount of fertilizers obtained by natural methods, On the other hand it has been observed that studies for obtaining different types (solid natural, liquid natural, bio-natural etc. of fertilizer have continued increasing. The aim of this study is to determine time depend (30 days, 31-60 days changes of some nutrients and metals in vermiwash obtained from Eisenia fetida fed with fermented natural cow dung. For this purpose, Eisenia fetida were fed with fermented cow dung which obtained from cows grazing in natural habitat and obtained vermiwash were analyzed to determined some macro and micronutrient elements. As a result of the study, while the values of N, K, Ca, Mg, Na, Fe, Ni, Cu, Zn, Hg, Sb in vermiwash decreased at a statistically significant level depending on the time; Co, As, Ag, Cd, Pb, Al, Se, Mo, Li and Be were increased at statistically significant levels.

  6. Molecular Characterization of Methicillin-Resistant Staphylococcus aureus from Outpatients in Northern Japan: Increasing Tendency of ST5/ST764 MRSA-IIa with Arginine Catabolic Mobile Element.

    Science.gov (United States)

    Aung, Meiji Soe; Kawaguchiya, Mitsuyo; Urushibara, Noriko; Sumi, Ayako; Ito, Masahiko; Kudo, Kenji; Morimoto, Shigeo; Hosoya, Shino; Kobayashi, Nobumichi

    2017-07-01

    Arginine catabolic mobile element (ACME) is a genomic island of staphylococcus and is considered to confer enhanced ability to survive and growth on host bacterial cells. ACME has been typically identified in Panton-Valentine Leukocidin (PVL)-positive ST8 methicillin-resistant Staphylococcus aureus (MRSA) with SCCmec type IVa (USA300 clone), and it is also found in other lineages at low frequency. Prevalence and molecular characteristics of PVL + and/or ACME + MRSA were investigated for 624 clinical isolates collected from outpatients in northern Japan from 2013 to 2014. Both PVL genes and ACME type I were detected in nine isolates (1.4%), which were ST8-MRSA-SCCmec IVa/spa type t008/agr-I; whereas solely PVL genes were positive in two isolates, ST30-MRSA-SCCmec IV and ST59-MRSA-SCCmec V. ACME type II' (previously referred to as ACME ΔII) was detected in 36 isolates (5.8%) with SCCmec II and V (32 and 4 isolates, respectively), exhibiting an increased rate within SCCmec II-MRSA (7.1%) compared with our previous studies (0.86-4.5%, 2008-2011). ACME II'-positive MRSA strains were classified into ST5-SCCmec IIa/V or ST764-SCCmec IIa belonging to five different spa types, with t002 being dominant. They harbored mostly enterotoxin gene clusters (seg-sei-sem-sen-seo-seu) and some more enterotoxin genes (seb1, seb2, sec3, sel, sep), showing resistance to more antimicrobials than ST8-MRSA-SCCmec IVa. ACME-SCCmec composite island (CI) of the 36 ACME II'-positive MRSA was classified into five types (ii)-(vi), among which type (ii) (orfX-ΨSCC ΔJ1 SCCmec I -ACME II'-SCCmec II) was dominant and subdivided into the A3 variant and the less common A2 variant. CI types (v) and (vi) were considered novel genetic organizations having speG (acetyltransferase genes for polyamines) in inserted SCC4610/SCC266-like genetic elements. The present study revealed increased prevalence and genetic diversity of the ST5/ST764-MRSA-SCCmec II with ACME II' in northern Japan.

  7. Accurate nonlinear modeling for flexible manipulators using mixed finite element formulation in order to obtain maximum allowable load

    International Nuclear Information System (INIS)

    Esfandiar, Habib; KoraYem, Moharam Habibnejad

    2015-01-01

    In this study, the researchers try to examine nonlinear dynamic analysis and determine Dynamic load carrying capacity (DLCC) in flexible manipulators. Manipulator modeling is based on Timoshenko beam theory (TBT) considering the effects of shear and rotational inertia. To get rid of the risk of shear locking, a new procedure is presented based on mixed finite element formulation. In the method proposed, shear deformation is free from the risk of shear locking and independent of the number of integration points along the element axis. Dynamic modeling of manipulators will be done by taking into account small and large deformation models and using extended Hamilton method. System motion equations are obtained by using nonlinear relationship between displacements-strain and 2nd PiolaKirchoff stress tensor. In addition, a comprehensive formulation will be developed to calculate DLCC of the flexible manipulators during the path determined considering the constraints end effector accuracy, maximum torque in motors and maximum stress in manipulators. Simulation studies are conducted to evaluate the efficiency of the method proposed taking two-link flexible and fixed base manipulators for linear and circular paths into consideration. Experimental results are also provided to validate the theoretical model. The findings represent the efficiency and appropriate performance of the method proposed.

  8. Accurate nonlinear modeling for flexible manipulators using mixed finite element formulation in order to obtain maximum allowable load

    Energy Technology Data Exchange (ETDEWEB)

    Esfandiar, Habib; KoraYem, Moharam Habibnejad [Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2015-09-15

    In this study, the researchers try to examine nonlinear dynamic analysis and determine Dynamic load carrying capacity (DLCC) in flexible manipulators. Manipulator modeling is based on Timoshenko beam theory (TBT) considering the effects of shear and rotational inertia. To get rid of the risk of shear locking, a new procedure is presented based on mixed finite element formulation. In the method proposed, shear deformation is free from the risk of shear locking and independent of the number of integration points along the element axis. Dynamic modeling of manipulators will be done by taking into account small and large deformation models and using extended Hamilton method. System motion equations are obtained by using nonlinear relationship between displacements-strain and 2nd PiolaKirchoff stress tensor. In addition, a comprehensive formulation will be developed to calculate DLCC of the flexible manipulators during the path determined considering the constraints end effector accuracy, maximum torque in motors and maximum stress in manipulators. Simulation studies are conducted to evaluate the efficiency of the method proposed taking two-link flexible and fixed base manipulators for linear and circular paths into consideration. Experimental results are also provided to validate the theoretical model. The findings represent the efficiency and appropriate performance of the method proposed.

  9. An Improved MLVF Method and Its Comparison with Traditional MLVF, spa Typing, MLST/SCCmec and PFGE for the Typing of Methicillin-Resistant Staphylococcus aureus

    Science.gov (United States)

    Du, Xue-Fei; Xiao, Meng; Liang, Hong-Yan; Sun, Zhe; Jiang, Yue-Hong; Chen, Guo-Yu; Meng, Xiao-Yu; Zou, Gui-Ling; Zhang, Li; Liu, Ya-Li; Zhang, Hui; Sun, Hong-Li; Jiang, Xiao-Feng; Xu, Ying-Chun

    2014-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become an important nosocomial pathogen, causing considerable morbidity and mortality. During the last 20 years, a variety of genotyping methods have been introduced for screening the prevalence of MRSA. In this study, we developed and evaluated an improved approach capillary gel electrophoresis based multilocus variable-number tandem-repeat fingerprinting (CGE/MLVF) for rapid MRSA typing. A total of 42 well-characterized strains and 116 non-repetitive clinical MRSA isolates collected from six hospitals in northeast China between 2009 and 2010 were tested. The results obtained by CGE/MLVF against clinical isolates were compared with traditional MLVF, spa typing, Multilocus sequence typing/staphylococcal cassette chromosome mec (MLST/SCCmec) and pulse field gel electrophoresis (PFGE). The discriminatory power estimated by Simpson’s index of diversity was 0.855 (28 types), 0.855 (28 patterns), 0.623 (11 types), 0.517 (8 types) and 0.854 (28 patterns) for CGE/MLVF, traditional MLVF, spa typing, MLST/SCCmec and PFGE, respectively. All methods tested showed a satisfied concordance in clonal complex level calculated by adjusted Rand’s coefficient. CGE/MLVF showed better reproducibility and accuracy than traditional MLVF and PFGE methods. In addition, the CGE/MLVF has potential to produce portable results. In conclusion, CGE/MLVF is a rapid and easy to use MRSA typing method with lower cost, good reproducibility and high discriminatory power for monitoring the outbreak and clonal spread of MRSA isolates. PMID:24406728

  10. Methicillin-resistant Staphylococcus aureus isolates with SCCmec type V and spa types t437 or t1081 associated to discordant susceptibility results between oxacillin and cefoxitin, Central Taiwan.

    Science.gov (United States)

    Ho, Cheng-Mao; Lin, Chien-Yu; Ho, Mao-Wang; Lin, Hsiao-Chuan; Chen, Chao-Jung; Lin, Lee-Chung; Lu, Jang-Jih

    2016-12-01

    Staphylococcus aureus isolates with discordant susceptibility results between oxacillin and cefoxitin obtained using automated microbiology systems are infrequently observed. From April 2013 to December 2014, 1956 methicillin-resistant S. aureus (MRSA) and 1761 methicillin-susceptible S. aureus isolates were obtained from different patients. Forty isolates (1.1% and 2% in case of S. aureus and MRSA, respectively) with discordant susceptibility results (oxacillin susceptible and cefoxitin resistant) and carrying mecA gene were obtained. Except 2 SCCmec type IV isolates, 38 MRSA isolates were all SCCmec type V (V T or non-V T ), which were further divided into V T (n=22) and non-V T (n=16). The most common spa type in V T and non-V T isolates were t437 (n=19) and t1081 (n=13), respectively. Only 55% of patients received effective antimicrobial agents; 2 mortalities were not attributable to MRSA infection. Using standard agar dilution, 17 MRSA isolates (0.46% and 0.87% in case of S. aureus and MRSA, respectively) had oxacillin MIC in the susceptible ranges (oxacillin-susceptible MRSA [OS-MRSA]); all carried SCCmec type V (V T , n=8; non-V T , n=9). The most common spa-MLST types of OS-MRSA in V T and non-V T were t437-ST59 (n=4) and t1081-ST45 (n=7), respectively. Concomitant testing by both cefoxitin- and oxacillin-based methods is a practical strategy for OS-MRSA detection in the clinical laboratories. Continuous monitoring of OS-MRSA isolates is necessary to elucidate their impact in clinical infectious diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Genetic diversity of methicillin resistant Staphylococcus aureus strains isolated from burn patients in Iran: ST239-SCCmec III/t037 emerges as the major clone.

    Science.gov (United States)

    Goudarzi, Mehdi; Bahramian, Mahnaz; Satarzadeh Tabrizi, Mahboobeh; Udo, Edet E; Figueiredo, Agnes Marie Sá; Fazeli, Maryam; Goudarzi, Hossein

    2017-04-01

    Methicillin-resistant Staphylococcus aureus (MRSA) as a major cause of infection in health care, hospital and community settings is a global health concern. The purpose of this study was to determine the antibiotic susceptibility pattern and distribution of circulating molecular types of MRSA in a burn hospital in Tehran, the capital of Iran. During a 10-month study period, 106 Staphylococcus aureus isolates were assessed. Isolates were subjected to susceptibility testing using the disk diffusion method and Polymerase Chain Reaction (PCR) for detection of mecA, fem and nuc genes. The presence of PVL and tst encoding genes were determined by PCR method. All the MRSA isolates were genotyped by multilocus sequence typing (MLST), spa typing, SCCmec typing and agr typing. The presence of mecA gene was confirmed in all the Staphylococcus aureus isolates. Antimicrobial susceptibility testing revealed a high resistance rate (90.6%) to ampicillin, tetracycline, and erythromycin. The rates of resistance to remaining antibiotics tested varied between 18.9% and 84.9%. The high- level of resistance to mupirocin was confirmed in 19.8% of MRSA strains isolated from burn patients. Multi-drug resistance was observed in 90.6% of isolates. Sixteen of the 106 MRSA isolates (15.1%) harbored PVL-encoding genes. The majority of our MRSA strains carried SCCmec III (71.7%). ST239-SCCmec III/t037 (34%) was the most common genotype followed by ST239-SCCmec III/t030 (24.5%), ST15-SCCmec IV/t084 (15.1%), ST22-SCCmec IV/t790 (13.2%), and ST239-SCCmec III/t631 (13.2%). Mupirocin resistant MRSA isolates belonged to ST15-SCCmec IV/t084 (40%), ST22-SCCmec IV/t790 (23.3%), ST239-SCCmec III/t631 (20%), and ST239-SCCmec III/t030 (16.7%) clones. The results showed that genetically diverse strains of MRSA are circulating in our burn hospitals with relatively high prevalence of ST239-SCCmec III/t037 clone. The findings support the need for regular surveillance of MRSA to determine the distribution of

  12. Methicillin-resistant Staphylococcus aureus carrying SCCmec type II was more frequent than the Brazilian endemic clone as a cause of nosocomial bacteremia.

    Science.gov (United States)

    Caiaffa-Filho, Helio Hehl; Trindade, Priscila A; Gabriela da Cunha, Paula; Alencar, Cecilia Salete; Prado, Gladys V B; Rossi, Flavia; Levin, Anna S

    2013-08-01

    Fifty consecutive MRSA blood isolates were evaluated: 30(60%) carried SCCmec type II (single PFGE clone; sequence type 5 or ST105); 12 (26%), IV; 5 (10%), III; 3 (6%), I. Brazilian endemic clone, carrying SCCmec type III, has been the main nosocomial clone in Brazil; however, this study showed that a clone carrying type II predominated. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Molecular Characterization of Methicillin Resistant Staphylococcus aureus Strains Isolated from Intensive Care Units in Iran: ST22-SCCmec IV/t790 Emerges as the Major Clone.

    Science.gov (United States)

    Goudarzi, Mehdi; Goudarzi, Hossein; Sá Figueiredo, Agnes Marie; Udo, Edet E; Fazeli, Maryam; Asadzadeh, Mohammad; Seyedjavadi, Sima Sadat

    2016-01-01

    The emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different patient populations is a major public health concern. This study determined the prevalence and distribution of circulating molecular types of MRSA in hospitalized patients in ICU of hospitals in Tehran. A total of 70 MRSA isolates were collected from patients in eight hospitals. Antimicrobial resistance patterns were determined using the disk diffusion method. The presence of toxin encoding genes and the vancomycin resistance gene were determined by PCR. The MRSA isolates were further analyzed using multi-locus sequence, spa, SCCmec, and agr typing. The MRSA prevalence was 93.3%. Antimicrobial susceptibility testing revealed a high resistance rate (97.1%) to ampicillin and penicillin. The rate of resistance to the majority of antibiotics tested was 30% to 71.4%. Two isolates belonging to the ST22-SCCmec IV/t790 clone (MIC ≥ 8 μg/ml) had intermediate resistance to vancomycin. The majority of MRSA isolates (24.3%) were associated with the ST22-SCCmec IV/t790 clone; the other MRSA clones were ST859-SCCmec IV/t969 (18.6%), ST239-SCCmec III/t037 (17.1%), and ST291-SCCmec IV/t030 (8.6%). The circulating MRSA strains in Iranian hospitals were genetically diverse with a relatively high prevalence of the ST22-SCCmec IV/t790 clone. These findings support the need for future surveillance studies on MRSA to better elucidate the distribution of existing MRSA clones and detect emergence of new MRSA clones.

  14. SCCmecFinder, a Web-Based Tool for Typing of Staphylococcal Cassette Chromosome mec in Staphylococcus aureus Using Whole-Genome Sequence Data.

    Science.gov (United States)

    Kaya, Hülya; Hasman, Henrik; Larsen, Jesper; Stegger, Marc; Johannesen, Thor Bech; Allesøe, Rosa Lundbye; Lemvigh, Camilla Koldbæk; Aarestrup, Frank Møller; Lund, Ole; Larsen, Anders Rhod

    2018-01-01

    Typing of methicillin-resistant Staphylococcus aureus (MRSA) is important in infection control and surveillance. The current nomenclature of MRSA includes the genetic background of the S. aureus strain determined by multilocus sequence typing (MLST) or equivalent methods like spa typing and typing of the mobile genetic element staphylococcal cassette chromosome mec (SCC mec ), which carries the mecA or mecC gene. Whereas MLST and spa typing are relatively simple, typing of SCC mec is less trivial because of its heterogeneity. Whole-genome sequencing (WGS) provides the essential data for typing of the genetic background and SCC mec , but so far, no bioinformatic tools for SCC mec typing have been available. Here, we report the development and evaluation of SCC mec Finder for characterization of the SCC mec element from S. aureus WGS data. SCC mec Finder is able to identify all SCC mec element types, designated I to XIII, with subtyping of SCC mec types IV (2B) and V (5C2). SCC mec elements are characterized by two different gene prediction approaches to achieve correct annotation, a Basic Local Alignment Search Tool (BLAST)-based approach and a k -mer-based approach. Evaluation of SCC mec Finder by using a diverse collection of clinical isolates ( n = 93) showed a high typeability level of 96.7%, which increased to 98.9% upon modification of the default settings. In conclusion, SCC mec Finder can be an alternative to more laborious SCC mec typing methods and is freely available at https://cge.cbs.dtu.dk/services/SCCmecFinder. IMPORTANCE SCC mec in MRSA is acknowledged to be of importance not only because it contains the mecA or mecC gene but also for staphylococcal adaptation to different environments, e.g., in hospitals, the community, and livestock. Typing of SCC mec by PCR techniques has, because of its heterogeneity, been challenging, and whole-genome sequencing has only partially solved this since no good bioinformatic tools have been available. In this

  15. Isolation and Characterization of Mobile Genetic Elements from Microbial Assemblages Obtained from the Field Research Center Site

    Energy Technology Data Exchange (ETDEWEB)

    Patricia Sobecky; Cassie Hodges; Kerri Lafferty; Mike Humphreys; Melanie Raimondo; Kristin Tuttle; Tamar Barkay

    2004-03-17

    Considerable knowledge has been gained from the intensive study of a relatively limited group of bacterial plasmids. Recent efforts have begun to focus on the characterization of, at the molecular level, plasmid populations and associated mobile genetic elements (e.g., transposons, integrons) occurring in a wider range of aquatic and terrestrial habitats. Surprisingly, however, little information is available regarding the incidence and distribution of mobile genetic elements extant in contaminated subsurface environments. Such studies will provide greater knowledge on the ecology of plasmids and their contributions to the genetic plasticity (and adaptation) of naturally occurring subsurface microbial communities. We requested soil cores from the DOE NABIR Field Research Center (FRC) located on the Oak Ridge Reservation. The cores, received in February 2003, were sampled from four areas on the Oak Ridge Site: Area 1, Area 2, Area 3 (representing contaminated subsurface locales) and the background reference sites. The average core length (24 in) was subdivided into three profiles and soil pH and moisture content were determined. Uranium concentration was also determined in bulk samples. Replicate aliquots were fixed for total cell counts and for bacterial isolation. Four different isolation media were used to culture aerobic and facultative microbes from these four study areas. Colony forming units ranged from a minimum of 100 per gram soil to a maximum of 10,000 irrespective of media composition used. The vast majority of cultured subsurface isolates were gram-positive isolates and plasmid characterization was conducted per methods routinely used in the Sobecky laboratory. The percentage of plasmid incidence ranged from 10% to 60% of all isolates tested. This frequency appears to be somewhat higher than the incidence of plasmids we have observed in other habitats and we are increasing the number of isolates screened to confirm this observation. We are also

  16. Analysis of X-ray Spectra of High-Z Elements obtained on Nike with high spectral and spatial resolution

    Science.gov (United States)

    Aglitskiy, Yefim; Weaver, J. L.; Karasik, M.; Serlin, V.; Obenschain, S. P.; Ralchenko, Yu.

    2014-10-01

    The spectra of multi-charged ions of Hf, Ta, W, Pt, Au and Bi have been studied on Nike krypton-fluoride laser facility with the help of two kinds of X-ray spectrometers. First, survey instrument covering a spectral range from 0.5 to 19.5 angstroms which allows simultaneous observation of both M- and N- spectra of above mentioned elements with high spectral resolution. Second, an imaging spectrometer with interchangeable spherically bent Quartz crystals that added higher efficiency, higher spectral resolution and high spatial resolution to the qualities of the former one. Multiple spectral lines with X-ray energies as high as 4 keV that belong to the isoelectronic sequences of Fe, Co, Ni, Cu and Zn were identified with the help of NOMAD package developed by Dr. Yu. Ralchenko and colleagues. In our continuous effort to support DOE-NNSA's inertial fusion program, this campaign covered a wide range of plasma conditions that result in production of relatively energetic X-rays. Work supported by the US DOE/NNSA.

  17. Development of a QGIS Plugin to Obtain Parameters and Elements of Plantation Trees and Vineyards with Aerial Photographs

    Directory of Open Access Journals (Sweden)

    Lia Duarte

    2018-03-01

    Full Text Available Unmanned Aerial Vehicle (UAV imagery allows for a new way of obtaining geographic information. In this work, a Geographical Information System (GIS open source application was developed in QGIS software that estimates several parameters and metrics on tree crown through image analysis techniques (image segmentation and image classification and fractal analysis. The metrics that have been estimated were: area, perimeter, number of trees, distance between trees, and a missing tree check. This methodology was tested on three different plantations: olive, eucalyptus, and vineyard. The application developed is free, open source and takes advantage of QGIS integration with external software. Several tools available from Orfeo Toolbox and Geographic Resources Analysis Support System (GRASS GIS were employed to generate a classified raster image which allows calculating the metrics referred before. The application was developed in the Python 2.7 language. Also, some functions, modules, and classes from the QGIS Application Programming Interface (API and PyQt4 API were used. This new plugin is a valuable tool, which allowed for automatizing several parameters and metrics on tree crown using GIS analysis tools, while considering data acquired by UAV.

  18. Recombinations in staphylococcal cassette chromosome mec elements compromise the molecular detection of methicillin resistance in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Grant A Hill-Cawthorne

    Full Text Available Clinical laboratories are increasingly using molecular tests for methicillin-resistant Staphylococcus aureus (MRSA screening. However, primers have to be targeted to a variable chromosomal region, the staphylococcal cassette chromosome mec (SCCmec. We initially screened 726 MRSA isolates from a single UK hospital trust by recombinase polymerase amplification (RPA, a novel, isothermal alternative to PCR. Undetected isolates were further characterised using multilocus sequence, spa typing and whole genome sequencing. 96% of our tested phenotypically MRSA isolates contained one of the six orfX-SCCmec junctions our RPA test and commercially available molecular tests target. However 30 isolates could not be detected. Sequencing of 24 of these isolates demonstrated recombinations within the SCCmec element with novel insertions that interfered with the RPA, preventing identification as MRSA. This result suggests that clinical laboratories cannot rely solely upon molecular assays to reliably detect all methicillin-resistance. The presence of significant recombinations in the SCCmec element, where the majority of assays target their primers, suggests that there will continue to be isolates that escape identification. We caution that dependence on amplification-based molecular assays will continue to result in failure to diagnose a small proportion (∼4% of MRSA isolates, unless the true level of SCCmec natural diversity is determined by whole genome sequencing of a large collection of MRSA isolates.

  19. Recombinations in staphylococcal cassette chromosome mec elements compromise the molecular detection of methicillin resistance in Staphylococcus aureus

    KAUST Repository

    Hill-Cawthorne, Grant A.

    2014-06-27

    Clinical laboratories are increasingly using molecular tests for methicillin-resistant Staphylococcus aureus (MRSA) screening. However, primers have to be targeted to a variable chromosomal region, the staphylococcal cassette chromosome mec (SCCmec). We initially screened 726 MRSA isolates from a single UK hospital trust by recombinase polymerase amplification (RPA), a novel, isothermal alternative to PCR. Undetected isolates were further characterised using multilocus sequence, spa typing and whole genome sequencing. 96% of our tested phenotypically MRSA isolates contained one of the six orfX-SCCmec junctions our RPA test and commercially available molecular tests target. However 30 isolates could not be detected. Sequencing of 24 of these isolates demonstrated recombinations within the SCCmec element with novel insertions that interfered with the RPA, preventing identification as MRSA. This result suggests that clinical laboratories cannot rely solely upon molecular assays to reliably detect all methicillin-resistance. The presence of significant recombinations in the SCCmec element, where the majority of assays target their primers, suggests that there will continue to be isolates that escape identification. We caution that dependence on amplification-based molecular assays will continue to result in failure to diagnose a small proportion (?4%) of MRSA isolates, unless the true level of SCCmec natural diversity is determined by whole genome sequencing of a large collection of MRSA isolates. © 2014 Hill-Cawthorne et al.

  20. Recombinations in staphylococcal cassette chromosome mec elements compromise the molecular detection of methicillin resistance in Staphylococcus aureus

    KAUST Repository

    Hill-Cawthorne, Grant A.; Hudson, Lyndsey O.; Abd El Ghany, Moataz; Piepenburg, Olaf; Nair, Mridul; Dodgson, Andrew; Forrest, Matthew S.; Clark, Taane G.; Pain, Arnab

    2014-01-01

    Clinical laboratories are increasingly using molecular tests for methicillin-resistant Staphylococcus aureus (MRSA) screening. However, primers have to be targeted to a variable chromosomal region, the staphylococcal cassette chromosome mec (SCCmec). We initially screened 726 MRSA isolates from a single UK hospital trust by recombinase polymerase amplification (RPA), a novel, isothermal alternative to PCR. Undetected isolates were further characterised using multilocus sequence, spa typing and whole genome sequencing. 96% of our tested phenotypically MRSA isolates contained one of the six orfX-SCCmec junctions our RPA test and commercially available molecular tests target. However 30 isolates could not be detected. Sequencing of 24 of these isolates demonstrated recombinations within the SCCmec element with novel insertions that interfered with the RPA, preventing identification as MRSA. This result suggests that clinical laboratories cannot rely solely upon molecular assays to reliably detect all methicillin-resistance. The presence of significant recombinations in the SCCmec element, where the majority of assays target their primers, suggests that there will continue to be isolates that escape identification. We caution that dependence on amplification-based molecular assays will continue to result in failure to diagnose a small proportion (?4%) of MRSA isolates, unless the true level of SCCmec natural diversity is determined by whole genome sequencing of a large collection of MRSA isolates. © 2014 Hill-Cawthorne et al.

  1. High frequency of multidrug-resistant Staphylococcus aureus with SCCmec type III and Spa types t037 and t631 isolated from burn patients in southwest of Iran.

    Science.gov (United States)

    Parhizgari, Najmeh; Khoramrooz, Seyed Sajjad; Malek Hosseini, Seyed Ali Asghar; Marashifard, Masoud; Yazdanpanah, Mahboobeh; Emaneini, Mohammad; Gharibpour, Farzaneh; Mirzaii, Mehdi; Darban-Sarokhalil, Davood; Moein, Masoud; Naraki, Mahmood

    2016-03-01

    Methicilin resistance Staphylococcus aureus (MRSA) infections are the major challenges in hospitals, especially in the burn units. The use of molecular typing methods is essential for tracking the spread of S. aureus infection and epidemiological investigations. The aim of this study was to find the profile of the spa types and also the prevalence of each SCCmec type of S. aureus strains in a central burn hospital in southwest of Iran. A total of 81 non-duplicate S. aureus were isolated from burn patients between April 2011 and February 2012. The susceptibility of the isolates against 13 different antibiotics was tested by disk agar diffusion (DAD) method. MRSA strains were identified by amplification of mecA gene. Multiplex-polymerase chain reaction (PCR) technique was used to determine the SCCmec types of MRSA strains and all the S. aureus isolates were typed by spa typing method. Detection of mecA gene showed that 70 (86.4%) of the isolates were MRSA. The highest rate of resistance was observed for penicillin (97.5%) and erythromycin (77.8%). None of the isolates were resistant to vancomycin. Sixty-seven of the 70 MRSA isolates harbored only SCCmec type III and three untypeable isolates. Five different spa types were detected. The most common spa types were t037 (42.5%) and t631 (34.5%) and were only found in MRSA isolates. Only SCCmec type III was found in burn patients which emphasizes the HA-MRSA origin of these strains. Only five different spa types identified in this study are in accordance with one SCCmec type which indicates that a limited number of bacterial colons are circulated in the burn unit in this hospital. © 2015 APMIS. Published by John Wiley & Sons Ltd.

  2. Methodology to obtain exchange properties of the calcite surface-Application to major and trace elements: Ca(II), HCO3-, and Zn(II)

    International Nuclear Information System (INIS)

    Tertre, E.; Beaucaire, C.; Juery, A.; Ly, J.; Tertre, E.; Beaucaire, C.; Juery, A.; Ly, J.

    2010-01-01

    Sorption of inorganic elements onto carbonate minerals has been intensively described in the literature by two reaction steps: (1) a first one rapid and completed within a few hours and (2) a second one slower, eventually irreversible, and occurring at a constant rate. The first step is often attributed to an ion-exchange process, but its reversibility is rarely investigated. Consequently, discrimination of the global sorption phenomenon into two different mechanisms is not always justified. In this study, we investigated, by batch experiments, both sorption and desorption of Ca(II), HCO 3 - , and Zn(II), radiolabeled with isotopes 45 Ca(II), H 14 CO 3 - , and 65 Zn(II), respectively, onto synthetic pure calcite. Solutions were pre-equilibrated with atmospheric p(CO 2 ) and saturated with respect to calcite. Therefore, our purpose was to: (1) obtain experimental distribution coefficients of major elements (Ca(II) and HCO 3 - ) and a trace element (Zn(II)) onto calcite from sorption and desorption experiments, (2) test the validity of a first-occurring ion-exchange process generally noted in the literature, by calculating distribution coefficients for the 'sole' exchange process, and (3) quantify the amounts of Ca(II), HCO 3 - , and Zn(II) sorbed on the calcite surface by the sole 'exchange process' and compare them with surface crystallochemical data. Ca(II) or HCO 3 - sorption experimental data suggest that a significant fraction of these two elements was sorbed irreversibly onto or in the calcite. By using a method based on isotopic ratios, the Ca(II) or HCO 3 - concentrations, which are reversibly adsorbed on the calcite, have been quantified. These concentrations are respectively estimated at 4. 0 ± 2. 0 * 10 -4 and 7. 0 ± 1. 5 * 10 -4 mol/kg. The obtained Ca(II) surface concentration value is one order of magnitude lower than the one obtained from isotopic measurement by former authors [Geochim. Cosmochim. Acta 55 (1991) 1549; Geochim. Cosmochim. Acta 51

  3. Characterization of a Novel Arginine Catabolic Mobile Element (ACME) and Staphylococcal Chromosomal Cassette mec Composite Island with Significant Homology to Staphylococcus epidermidis ACME type II in Methicillin-Resistant Staphylococcus aureus Genotype ST22-MRSA-IV.

    LENUS (Irish Health Repository)

    Shore, Anna C

    2011-02-22

    The arginine catabolic mobile element (ACME) is prevalent among ST8-MRSA-IVa (USA300) isolates and evidence suggests that ACME enhances the ability of ST8-MRSA-IVa to grow and survive on its host. ACME has been identified in a small number of isolates belonging to other MRSA clones but is widespread among coagulase-negative staphylococci (CoNS). This study reports the first description of ACME in two distinct strains of the pandemic ST22-MRSA-IV clone. A total of 238 MRSA isolates recovered in Ireland between 1971 and 2008 were investigated for ACME using a DNA microarray. Twenty-three isolates (9.7%) were ACME-positive, all were either MRSA genotype ST8-MRSA-IVa (7\\/23, 30%) or ST22-MRSA-IV (16\\/23, 70%). Whole-genome sequencing and comprehensive molecular characterization revealed the presence of a novel 46-kb ACME and SCCmec composite island (ACME\\/SCCmec-CI) in ST22-MRSA-IVh isolates (n = 15). This ACME\\/SCCmec-CI consists of a 12-kb DNA region previously identified in ACME type II in S. epidermidis ATCC 12228, a truncated copy of the J1 region of SCCmec I and a complete SCCmec IVh element. The composite island has a novel genetic organization with ACME located within orfX and SCCmec located downstream of ACME. One pvl-positive ST22-MRSA-IVa isolate carried ACME located downstream of SCCmec IVa as previously described in ST8-MRSA-IVa. These results suggest that ACME has been acquired by ST22-MRSA-IV on two independent occasions. At least one of these instances may have involved horizontal transfer and recombination events between MRSA and CoNS. The presence of ACME may enhance dissemination of ST22-MRSA-IV, an already successful MRSA clone.

  4. Role of integrons, plasmids and SXT elements in multidrug resistance of Vibrio cholerae and Providencia vermicola obtained from a clinical isolate of diarrhea

    Directory of Open Access Journals (Sweden)

    Neha eRajpara

    2015-02-01

    Full Text Available The isolates of Vibrio cholerae and Providencia vermicola obtained from a diarrhoeal patient were investigated for genetic elements governing their drug resistance phenotypes. Out of fourteen antibiotics tested, V. cholerae Vc IDH02365 isolate showed resistance to nine antibiotics, while P. vermicola Pv NBA2365 was found to be resistant to all the antibiotics except polymyxin B. Though SXT integrase was depicted in both the bacteria, class 1 integron was found to be associated only with Pv NBA2365. Integrons in Pv NBA2365 conferred resistance to β-lactams, aminoglycosides and trimethoprim. Pv NBA2365 carried two transformable plasmids imparting distinct antibiotic resistance traits to their Escherichia coli transformants. In rabbit ileal loop assays, Pv NBA2365 did not show any fluid accumulation in contrast with Vc IDH02365 that showed high fluid accumulation. To the best of our knowledge, this is the first report of a highly drug resistant P.vermicola and additionally co-existence of multidrug resistant V. cholerae and P. vermicola. Both the microbes appeared to possess a wide array of mobile genetic elements for a large spectrum of antimicrobial agents, some of which are being used in the treatment of acute diarrhoea.

  5. Comparative Genotypes, Staphylococcal Cassette Chromosome mec (SCCmec) Genes and Antimicrobial Resistance amongst Staphylococcus epidermidis and Staphylococcus haemolyticus Isolates from Infections in Humans and Companion Animals

    OpenAIRE

    McManus, Brenda A.; Coleman, David C.; Deasy, Emily C.; Brennan, Gráinne I.; O’ Connell, Brian; Monecke, Stefan; Ehricht, Ralf; Leggett, Bernadette; Leonard, Nola; Shore, Anna C.

    2015-01-01

    This study compares the characteristics of Staphylococcus epidermidis (SE) and Staphylococcus haemolyticus (SH) isolates from epidemiologically unrelated infections in humans (Hu) (28 SE-Hu; 8 SH-Hu) and companion animals (CpA) (12 SE-CpA; 13 SH-CpA). All isolates underwent antimicrobial susceptibility testing, multilocus sequence typing and DNA microarray profiling to detect antimicrobial resistance and SCCmec-associated genes. All methicillin-resistant (MR) isolates (33/40 SE, 20/21 SH) und...

  6. Synthesis and evaluation of germanic organometallic compounds as precursors for chemical vapor deposition (CVD) and for obtaining nanoparticles of elemental germanium

    International Nuclear Information System (INIS)

    Ballestero Martinez, Ernesto

    2014-01-01

    The interest in the development of materials that have applications in areas such as electronics or biomarkers has affected the synthesis of new compounds based on germanium. This element has two states of common oxidation, +4 and +2, of them, the +2 oxidation state is the least studied and more reactive. Additionally, compounds of germanium (II) have similarities to carbenes in terms Lewis'acid base chemistry. The preparation of compounds of germanium (II) with ligands β-diketiminates has made possible the stabilization of new chemical functionalities and, simultaneously, it has provided interesting thermal properties to develop new methods of preparation of materials with novel properties. The preparation of amides germanium (II) L'Ge (NHPh) [1, L'= {HC (CMeN-2,4,6-Me 3 C 6 H 2 ) 2 } - ], L'Ge (4-NHPy) [2], L'Ge (2-NHPy) [3] and LGe(2-NHPy) [4, L = {HC (CMeN-2,6- i Pr 2 C 6 H 3 ) 2 ] - ] are presented, the chemical and structural composition was determined by using techniques such as nuclear magnetic resonance ( 1 H, 13 C), elemental analysis, melting point, infrared spectroscopy, X-ray diffraction of single crystal and thermogravimetric analysis (TGA). The TGA has demonstrated that 1-4 experience a thermal decomposition, therefore, these compounds could be considered as potential starting materials for the obtaining of germanium nitride (GeN x ). Certainly, the availability of coordinating nitrogen atoms in the chemical composition in 2-4 have been interesting given that it could act as ligands in reactions with transition metal complexes. Thus, relevant information to molecular level could be obtained for some reactions and interactions that have used similar link sites in surface chemistry, for example, the chemical functionalization of silicon and germanium substrate. Additionally, the synthesis and structural characterization of germanium chloride compound (II) L G eCl [5, L' = HC{(CMe) (N-2,6-Me 2 C 6 H 3 )} 2 - ] is reported

  7. The human clone ST22 SCCmec IV methicillin-resistant Staphylococcus aureus isolated from swine herds and wild primates in Nepal: is man the common source?

    Science.gov (United States)

    Roberts, Marilyn C; Joshi, Prabhu Raj; Greninger, Alexander L; Melendez, Daira; Paudel, Saroj; Acharya, Mahesh; Bimali, Nabin Kishor; Koju, Narayan P; No, David; Chalise, Mukesh; Kyes, Randall C

    2018-05-01

    Swine nasal samples [n = 282] were collected from 12 randomly selected farms around Kathmandu, Nepal, from healthy animals. In addition, wild monkey (Macaca mulatta) saliva samples [n = 59] were collected near temples areas in Kathmandu using a non-invasive sampling technique. All samples were processed for MRSA using standardized selective media and conventional biochemical tests. MRSA verification was done and isolates characterized by SCCmec, multilocus sequence typing, whole genome sequencing [WGS] and antibiotic susceptibilities. Six (2.1%) swine MRSA were isolated from five of the different swine herds tested, five were ST22 type IV and one ST88 type V. Four (6.8%) macaques MRSA were isolated, with three ST22 SCCmec type IV and one ST239 type III. WGS sequencing showed that the eight ciprofloxacin resistant ST22 isolates carried gyrA mutation [S84L]. Six isolates carried the erm(C) genes, five isolates carried aacC-aphD genes and four isolates carried blaZ genes. The swine linezolid resistant ST22 did not carry any known acquired linezolid resistance genes but had a mutation in ribosomal protein L22 [A29V] and an insertion in L4 [68KG69], both previously associated with linezolid resistance. Multiple virulence factors were also identified. This is the first time MRSA ST22 SCCmec IV has been isolated from livestock or primates.

  8. Cost-effectiveness and efficacy of spa, SCCmec, and PVL genotyping of methicillin-resistant Staphylococcus aureus as compared to pulsed-field gel Electrophoresis.

    Directory of Open Access Journals (Sweden)

    Vincent Li

    Full Text Available Pulsed-field gel electrophoresis (PFGE is a valuable molecular typing assay used for methicillin-resistant Staphylococcus aureus (MRSA surveillance and genotyping. However, there are several limitations associated with PFGE. In Alberta, Canada, the significant increase in the number of MRSA isolates submitted to the Provincial Laboratory for Public Health (ProvLab for PFGE typing led to the need for an alternative genotyping method. In this study, we describe the transition from PFGE to Staphylococcus protein A (spa, Staphylococcal cassette chromosome (SCCmec, and Panton-Valentine leukocidin (PVL typing. A total of 1915 clinical MRSA isolates collected from 2005 to 2009 were used to develop and validate an algorithm for assigning PFGE epidemic types using spa, SCCmec, and PVL typing and the resulting data was used to populate a new Alberta MRSA typing database. An additional 12620 clinical MRSA isolates collected from 2010 to 2012 as part of ongoing routine molecular testing at ProvLab were characterized using the new typing algorithm and the Alberta MRSA typing database. Switching to spa, SCCmec, and PVL from PFGE typing substantially reduced hands-on and turn-around times while maintaining historical PFGE epidemic type designations. This led to an approximate $77,000 reduction in costs from 2010 to 2012. PFGE typing is still required for a small subset of MRSA isolates that have spa types that are rare, novel, or associated with more than one PFGE epidemic type.

  9. Determination of staphylococcal exotoxins, SCCmec types, and genetic relatedness of Staphylococcus intermedius group isolates from veterinary staff, companion animals, and hospital environments in Korea

    Science.gov (United States)

    Youn, Jung-Ho; Ahn, Kuk Ju; Lim, Suk-Kyung

    2011-01-01

    The Staphylococcus (S.) intermedius group (SIG) has been a main research subject in recent years. S. pseudintermedius causes pyoderma and otitis in companion animals as well as foodborne diseases. To prevent SIG-associated infection and disease outbreaks, identification of both staphylococcal exotoxins and staphylococcal cassette chromosome mec (SCCmec) types among SIG isolates may be helpful. In this study, it was found that a single isolate (one out of 178 SIG isolates examined) harbored the canine enterotoxin SEC gene. However, the S. intermedius exfoliative toxin gene was found in 166 SIG isolates although the S. aureus-derived exfoliative toxin genes, such as eta, etb and etd, were not detected. SCCmec typing resulted in classifying one isolate as SCCmec type IV, 41 isolates as type V (including three S. intermedius isolates), and 10 isolates as non-classifiable. Genetic relatedness of all S. pseudintermedius isolates recovered from veterinary staff, companion animals, and hospital environments was determined by pulsed-field gel electrophoresis. Strains having the same band patterns were detected in S. pseudintermedius isolates collected at 13 and 18 months, suggesting possible colonization and/or expansion of a specific S. pseudintermedius strain in a veterinary hospital. PMID:21897094

  10. Methicillin-resistant Staphylococcus aureus in Rio de Janeiro hospitals: dissemination of the USA400/ST1 and USA800/ST5 SCCmec type IV and USA100/ST5 SCCmec type II lineages in a public institution and polyclonal presence in a private one.

    Science.gov (United States)

    Caboclo, Roberta Mello Ferreira; Cavalcante, Fernanda Sampaio; Iorio, Natalia Lopes Pontes; Schuenck, Ricardo Pinto; Olendzki, André Nogueira; Felix, Maria José; Chamon, Raiane Cardoso; dos Santos, Kátia Regina Netto

    2013-03-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections have changed since certain non-multiresistant MRSA lineages have emerged in hospitals. In this study, 99 MRSA isolates, 77 from a public and 22 from a private hospital, were characterized. Isolates were tested for antimicrobial susceptibility, whereas staphylococcal chromosomal cassette mec (SCCmec) typing and Panton-Valentine leukocidin genes were assessed by polymerase chain reaction. Pulsed-field gel electrophoresis and multilocus sequence typing analyses were carried out to determine the MRSA lineages. High rates of resistance were found to erythromycin (96%), ciprofloxacin (93%), and clindamycin (90%). The SCCmec types found were as follows: type II (14.2%), III (62.6%), and IV (23.2%). Approximately 85% of type III isolates was related to the Brazilian epidemic clone in both hospitals. For type IV isolates, 94.4% were related to both USA400/ sequence type (ST) 1 and USA800/ST5 lineages in the public hospital, whereas the USA400/ST1, USA800/ST5, USA1100/ST30, and EMRSA (Epidemic MRSA)-15/ST22 lineages were detected in the private hospital. Among the SCCmec II isolates, approximately 85% were related to the USA100/ST5 lineage. Three MRSA isolates were positive to Panton-Valentine leukocidin genes. The study showed that there was an emergence of USA400/ST1, USA800/ST5 SCCmec IV, and USA100/ST5 SCCmec II MRSA lineages in both hospitals. There was a dissemination of them in the public hospital and a polyclonal presence of the MRSA isolates in the private hospital. The spread of these lineages can be facilitated by the characteristics of the health institution. Copyright © 2013 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  11. Synthesis and evaluation of germanium organometallic compounds as precursors for chemical vapor deposition (CVD) and for obtaining nanoparticles of elemental germanium

    International Nuclear Information System (INIS)

    Ballestero Martinez, Ernesto

    2014-01-01

    The interest in the development of materials having applications such as electronics areas or biomarkers has affected the synthesis of new compounds based on germanium. This element has had two common oxidation states, +4 and +2, of them, +2 oxidation state has been the least studied and more reactive. Additionally, compounds of germanium (II) have had similarities with carbenes regarding the chemical acid-base Lewis. The preparation of compounds of germanium (II) with ligands β-decimations has enabled stabilization of new chemical functionalities and, simultaneously, provided interesting thermal properties to develop new preparation methodologies of materials with novel properties. The preparation of amides germanium(II) L'Ge(NHPh) [1, L' = {HC (CMeN-2,4,6-Me 3 C 6 H 2 ) 2 }], L'Ge(4-NHPy) [2] L'Ge(2-NHPy) [3] and LGe(2-NHPy) [4, L = {HC(CMeN-2,6- i Pr 2 C 6 H 3 ) 2 }]; the structural chemical composition were determined using techniques such as nuclear magnetic resonance ( 1 H, 13 C), other techniques are treated: elemental analysis, melting point, infrared spectroscopy, X-ray diffraction of single crystal and thermal gravimetric analysis (TGA). The TGA has showed that 4-1 have experimented a thermal decomposition; therefore, these compounds could be considered as potential starting materials for obtaining germanium nitride (GeN x ). Certainly, the availability of nitrogen coordinating atoms in the chemical composition in 2-4 have been interesting because it could act as ligands in reactions with transition metal complexes. That way, information could be obtained at the molecular level for some reactions and interactions that in surface chemistry have used similar link sites, for example, chemical functionalization of silicon and germanium substrates. The synthesis and structural characterization of germanium chloride compound(II) L''GeCl [5, L'' = HC{(CMe) (N-2,6-Me 2 C 6 H 3 )} 2 ], which could be used later for the

  12. Prevalence of coagulase-negative staphylococci and determination of antimicrobial resistance in accompany with types of SCCmec in isolated of nosocomial infections

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arabestani

    2016-03-01

    Full Text Available Background: Coagulase-negative staphylococci (CoNS were considered as contaminats previously, but, during the past decade considered as one of the most common photogenic bacteria in hospital. Resistance to beta-lactams especially methicillin in staphylococcus species is being worrying in hospitals. Rapid identification of mechanisms of resistance and confirmation of their resistance to methicillin is a basic principle for antibiotic treatment. The aim of this study was to determine antibiotic resistance, frequency of mecA gene, and determination of SCCmec types in CoNS isolates from teaching hospitals in Iran. Methods: The descriptive cross-sectional study was carried out one hundred clinical samples isolated from patients with an average age of 7-69 years at teaching hospitals in Hamadan City, Iran, from September 2014 to February 2015. After confirmation of isolates by microbiological standard biochemical tests, antimicrobial susceptibility testing was performed by disk agar diffusion (DAD method. After extraction of isolated genomicm, mecA gene was detected. Then, the types of SCCmec were performed by PCR. Results: In this study, 387 clinical samples were collected which among 100 CoNS isolated, Staphylococcus epidermidis was the most prevalent species with frequency 55 (55%, followed by S. haemolyticus 40(40% and S. saprophyticus 5(5%. The highest antibiotic susceptibility was to rifampin 96(96% and the lowest resistance was detected for trimethoprim/sulfamethoxazole (TMP/SMX 47(47%. None of the strains were resistant to vancomycin. Resistance to methicillin was detected in 50% of CoNS isolates. Typing of SCCmec was performed by The polymerase chain reaction (PCR. Frequency types of SCCmec was type III with frequency 13(13%, type V 11(11%, type II 6(6%, type IV 4 (4%, type I 3(3% respectively. Thirteen isolated was not typable in this study. Conclusion: The result of this study showed that a large percentage of coagulase

  13. Microscale soil structure development after glacial retreat - using machine-learning based segmentation of elemental distributions obtained by NanoSIMS

    Science.gov (United States)

    Schweizer, Steffen; Schlueter, Steffen; Hoeschen, Carmen; Koegel-Knabner, Ingrid; Mueller, Carsten W.

    2017-04-01

    Soil organic matter (SOM) is distributed on mineral surfaces depending on physicochemical soil properties that vary at the submicron scale. Nanoscale secondary ion mass spectrometry (NanoSIMS) can be used to visualize the spatial distribution of up to seven elements simultaneously at a lateral resolution of approximately 100 nm from which patterns of SOM coatings can be derived. Existing computational methods are mostly confined to visualization and lack spatial quantification measures of coverage and connectivity of organic matter coatings. This study proposes a methodology for the spatial analysis of SOM coatings based on supervised pixel classification and automatic image analysis of the 12C, 12C14N (indicative for SOM) and 16O (indicative for mineral surfaces) secondary ion distributions. The image segmentation of the secondary ion distributions into mineral particle surface and organic coating was done with a machine learning algorithm, which accounts for multiple features like size, color, intensity, edge and texture in all three ion distributions simultaneously. Our workflow allowed the spatial analysis of differences in the SOM coverage during soil development in the Damma glacier forefield (Switzerland) based on NanoSIMS measurements (n=121; containing ca. 4000 particles). The Damma chronosequence comprises several stages of soil development with increasing ice-free period (from ca. 15 to >700 years). To investigate mineral-associated SOM in the developing soil we obtained clay fractions (2.2 g cm3). We found increased coverage and a simultaneous development from patchy-distributed organic coatings to more connected coatings with increasing time after glacial retreat. The normalized N:C ratio (12C14N: (12C14N + 12C)) on the organic matter coatings was higher in the medium-aged soils than in the young and mature ones in both heavy and light mineral fraction. This reflects the sequential accumulation of proteinaceous SOM in the medium-aged soils and C

  14. Multiple-locus variable number of tandem repeats fingerprinting (MLVF) and virulence factor analysis of methicillin resistant Staphylococcus aureus SCCmec type III.

    Science.gov (United States)

    Emaneini, Mohammad; Jabalameli, Leila; Iman-Eini, Hossein; Aligholi, Marzieh; Ghasemi, Amir; Nakhjavani, Farrokh Akbari; Taherikalani, Morovat; Khoramian, Babak; Asadollahi, Parisa; Jabalameli, Fereshteh

    2011-01-01

    Methicillin resistant Staphylococcus aureus (MRSA), particularly strains with type III staphylococcal cassette chromosome mec (SCCmec), represent a serious human pathogen in Tehran, Iran. The disease-causing capability depends on their ability to produce a wide variety of virulent factors. The prevalence of exotoxin genes and multiple-locus variable number of tandem repeats fingerprinting (MLVF) profile among MRSA isolates, from patients in Tehran, was evaluated by PCR and Multiplex-PCR. The MLVF typing of 144 MRSA isolates with type III SCCmec produced 5 different MLVF types. Generally, 97.2% (140/144) of all the isolates were positive for at least one of the tested exotoxin genes. The most prevalent genes were hld, found in 87.5% (126/144) of the isolates followed by lukE-lukD and hla found in 72.9% (105/144) and 70.1% (101/144) of the isolates, respectively. The tst gene, belonging to MLVF types I, IV and V, was found among three of the isolates from blood and wound samples. The sea gene was detected in 58.3% (84/144) of the isolates and the sed and see genes were found in one isolate with MLVF type V. The coexistence of genes was observed in the 87.5% (126/144) of the isolates. The rate of coexistence of hld with lukE-lukD, hla with lukE-lukD and sea with lukE-lukD were 66.7% (96/144), 44.4% (64/144) and 44.4% (64/144), respectively. The present study demonstrated that MRSA strains with type III SCCmec show different MLVF patterns and exotoxin profiles.

  15. Molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from patients with bacteremia based on MLST, SCCmec, spa, and agr locus types analysis.

    Science.gov (United States)

    Goudarzi, Mehdi; Seyedjavadi, Sima Sadat; Nasiri, Mohammad Javad; Goudarzi, Hossein; Sajadi Nia, Raheleh; Dabiri, Hossein

    2017-03-01

    The widespread emergence of methicillin resistant Staphylococcus aureus, as a common cause of nosocomial infections, is becoming a serious concern in global public health. The objective of the present study was to investigate antimicrobial susceptibility pattern, frequency of virulence genes and molecular characteristics of methicillin-resistant Staphylococcus aureus strains isolated from patients with bacteremia. A total of 128 methicillin-resistant Staphylococcus aureus isolates were collected during February 2015 to January 2016. In vitro antimicrobial susceptibility of the isolates was assessed using the disk diffusion method. Conventional PCR was performed for the detection of adhesion (can, bbp, ebp, fnbB, fnbA, clfB, clfA) and toxin (etb, eta, pvl, tst) encoding genes, determining the agr type, SCCmec, MLST and spa typing of the isolates. All the methicillin-resistant Staphylococcus aureus isolates were found to be sensitive to linezolid, teicoplanin, and vancomycin. Resistance to the tested antibiotics varied from 97.7% for penicillin to 24.2% for mupirocin. The rate of multi drug resistance (MDR) in the present study was 97.7%. The most commonly detected toxin and adhesion genes were tst (58.6%), and clfB (100%), respectively. The majority of SCCmec III isolates were found in agr group I while SCCmec IV and II isolates were distributed among agr group III. Multilocus Sequence Typing (MLST) of the MRSA isolates showed five different sequence types: ST239 (43%), ST22 (39.8%), ST585 (10.9%), ST45 (3.9%) and ST240 (2.3%). All of the pvl positive strains belonged to ST22-SCCmec IV/t790 clone and were MDR. Among different 7 spa types, the most common were t790 (27.3%), t037 (21.9%), and t030 (14.1%). spa types t016, t924 and spa type t383 were reported for the first time from Asia and Iran, respectively. It was shown that spa types circulating in the studied hospitals varied which support the need to perform future surveillance studies in order to understand

  16. Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus ST30-SCCmecIVc-spat019-PVL positive in San Antonio de Areco, Argentina

    Directory of Open Access Journals (Sweden)

    Silvina Fernández

    2015-03-01

    Full Text Available Community-acquired methicillin-resistant Staphylococcus aureus is the first cause of skin and soft tissue infections, but can also produce severe diseases such as bacteremia, osteomyelitis and necrotizing pneumonia. Some S. aureus lineages have been described in cases of necrotizing pneumonia worldwide, usually in young, previously healthy patients. In this work, we describe a fatal case of necrotizing pneumonia due to community-acquired methicillin-resistant S. aureus clone ST30-SCCmecIVc-spat019-PVL positive in an immunocompetent adult patient.

  17. Community-acquired necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus ST30-SCCmecIVc-spat019-PVL positive in San Antonio de Areco, Argentina.

    Science.gov (United States)

    Fernandez, Silvina; Murzicato, Sofía; Sandoval, Orlando; Fernández-Canigia, Liliana; Mollerach, Marta

    2015-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus is the first cause of skin and soft tissue infections, but can also produce severe diseases such as bacteremia, osteomyelitis and necrotizing pneumonia. Some S. aureus lineages have been described in cases of necrotizing pneumonia worldwide, usually in young, previously healthy patients. In this work, we describe a fatal case of necrotizing pneumonia due to community-acquired methicillin-resistant S. aureus clone ST30-SCCmecIVc-spat019-PVL positive in an immunocompetent adult patient. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Complete Circular Genome Sequence of Successful ST8/SCCmecIV Community-Associated Methicillin-Resistant Staphylococcus aureus (OC8 in Russia: One-Megabase Genomic Inversion, IS256's Spread, and Evolution of Russia ST8-IV.

    Directory of Open Access Journals (Sweden)

    Tsai-Wen Wan

    Full Text Available ST8/SCCmecIV community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA has been a common threat, with large USA300 epidemics in the United States. The global geographical structure of ST8/SCCmecIV has not yet been fully elucidated. We herein determined the complete circular genome sequence of ST8/SCCmecIVc strain OC8 from Siberian Russia. We found that 36.0% of the genome was inverted relative to USA300. Two IS256, oppositely oriented, at IS256-enriched hot spots were implicated with the one-megabase genomic inversion (MbIN and vSaβ split. The behavior of IS256 was flexible: its insertion site (att sequences on the genome and junction sequences of extrachromosomal circular DNA were all divergent, albeit with fixed sizes. A similar multi-IS256 system was detected, even in prevalent ST239 healthcare-associated MRSA in Russia, suggesting IS256's strong transmission potential and advantage in evolution. Regarding epidemiology, all ST8/SCCmecIVc strains from European, Siberian, and Far Eastern Russia, examined had MbIN, and geographical expansion accompanied divergent spa types and resistance to fluoroquinolones, chloramphenicol, and often rifampicin. Russia ST8/SCCmecIVc has been associated with life-threatening infections such as pneumonia and sepsis in both community and hospital settings. Regarding virulence, the OC8 genome carried a series of toxin and immune evasion genes, a truncated giant surface protein gene, and IS256 insertion adjacent to a pan-regulatory gene. These results suggest that unique single ST8/spa1(t008/SCCmecIVc CA-MRSA (clade, Russia ST8-IVc emerged in Russia, and this was followed by large geographical expansion, with MbIN as an epidemiological marker, and fluoroquinolone resistance, multiple virulence factors, and possibly a multi-IS256 system as selective advantages.

  19. Complete Circular Genome Sequence of Successful ST8/SCCmecIV Community-Associated Methicillin-Resistant Staphylococcus aureus (OC8) in Russia: One-Megabase Genomic Inversion, IS256's Spread, and Evolution of Russia ST8-IV.

    Science.gov (United States)

    Wan, Tsai-Wen; Khokhlova, Olga E; Iwao, Yasuhisa; Higuchi, Wataru; Hung, Wei-Chun; Reva, Ivan V; Singur, Olga A; Gostev, Vladimir V; Sidorenko, Sergey V; Peryanova, Olga V; Salmina, Alla B; Reva, Galina V; Teng, Lee-Jene; Yamamoto, Tatsuo

    2016-01-01

    ST8/SCCmecIV community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been a common threat, with large USA300 epidemics in the United States. The global geographical structure of ST8/SCCmecIV has not yet been fully elucidated. We herein determined the complete circular genome sequence of ST8/SCCmecIVc strain OC8 from Siberian Russia. We found that 36.0% of the genome was inverted relative to USA300. Two IS256, oppositely oriented, at IS256-enriched hot spots were implicated with the one-megabase genomic inversion (MbIN) and vSaβ split. The behavior of IS256 was flexible: its insertion site (att) sequences on the genome and junction sequences of extrachromosomal circular DNA were all divergent, albeit with fixed sizes. A similar multi-IS256 system was detected, even in prevalent ST239 healthcare-associated MRSA in Russia, suggesting IS256's strong transmission potential and advantage in evolution. Regarding epidemiology, all ST8/SCCmecIVc strains from European, Siberian, and Far Eastern Russia, examined had MbIN, and geographical expansion accompanied divergent spa types and resistance to fluoroquinolones, chloramphenicol, and often rifampicin. Russia ST8/SCCmecIVc has been associated with life-threatening infections such as pneumonia and sepsis in both community and hospital settings. Regarding virulence, the OC8 genome carried a series of toxin and immune evasion genes, a truncated giant surface protein gene, and IS256 insertion adjacent to a pan-regulatory gene. These results suggest that unique single ST8/spa1(t008)/SCCmecIVc CA-MRSA (clade, Russia ST8-IVc) emerged in Russia, and this was followed by large geographical expansion, with MbIN as an epidemiological marker, and fluoroquinolone resistance, multiple virulence factors, and possibly a multi-IS256 system as selective advantages.

  20. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    International Nuclear Information System (INIS)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A.G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R.B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-01-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM 10 samples were collected in Megalopolis during the years 2009–11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11–33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m 3 ), biomass burning 19% (4.43 ± 0.27 μg/m 3 ), road dust 15% (3.63 ± 0.37 μg/m 3 ), power plant emissions 13% (3.01 ± 0.44 μg/m 3 ), traffic 12% (2.82 ± 0.37 μg/m 3 ), and sea spray 8% (1.99 ± 0.41 μg/m 3 ). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season

  1. Source apportionment by PMF on elemental concentrations obtained by PIXE analysis of PM10 samples collected at the vicinity of lignite power plants and mines in Megalopolis, Greece

    Science.gov (United States)

    Manousakas, M.; Diapouli, E.; Papaefthymiou, H.; Migliori, A.; Karydas, A. G.; Padilla-Alvarez, R.; Bogovac, M.; Kaiser, R. B.; Jaksic, M.; Bogdanovic-Radovic, I.; Eleftheriadis, K.

    2015-04-01

    Particulate matter (PM) is an important constituent of atmospheric pollution especially in areas under the influence of industrial emissions. Megalopolis is a small city of 10,000 inhabitants located in central Peloponnese in close proximity to three coal opencast mines and two lignite fired power plants. 50 PM10 samples were collected in Megalopolis during the years 2009-11 for elemental and multivariate analysis. For the elemental analysis PIXE was used as one of the most effective techniques in APM analytical characterization. Altogether, the concentrations of 22 elements (Z = 11-33), whereas Black Carbon was also determined for each sample using a reflectometer. Factorization software was used (EPA PMF 3.0) for source apportionment analysis. The analysis revealed that major emission sources were soil dust 33% (7.94 ± 0.27 μg/m3), biomass burning 19% (4.43 ± 0.27 μg/m3), road dust 15% (3.63 ± 0.37 μg/m3), power plant emissions 13% (3.01 ± 0.44 μg/m3), traffic 12% (2.82 ± 0.37 μg/m3), and sea spray 8% (1.99 ± 0.41 μg/m3). Wind trajectories have suggested that metals associated with emission from the power plants came mainly from west and were connected with the locations of the lignite mines located in this area. Soil resuspension, road dust and power plant emissions increased during the warm season of the year, while traffic/secondary, sea spray and biomass burning become dominant during the cold season.

  2. Certification of trace element contents (As, Cd, Co, Cu, Fe, Mn, Hg, Na, Pb and Zn) in a fly ash obtained from the combustion of pulverised coal

    International Nuclear Information System (INIS)

    Griepink, B.; Colinet, E.; Guzzi, G.; Haemers, L.; Muntau, H.

    1983-01-01

    The element contents of As, Cd, Co, Cu, Fe, Mn, Hg, Na, Pb and Zn of a fly ash from pulverised coal are certified. The procedures and their results for the homogenisation, the contamination and homogeneity checks and the analytical campaign are reported. The certified mass fractions and indicative values for Cr, Ni, Th, V and water soluble sulphate are given. The work was carried out within the framework of the activities of the Community Bureau of Reference (BCR) of the Commission of the European Communities. (orig.) [de

  3. Quasi-static method and finite element method for obtaining the modifications of the spontaneous emission rate and energy level shift near a plasmonic nanostructure.

    Science.gov (United States)

    Zhao, Yun-Jin; Tian, Meng; Wang, Xiao-Yun; Yang, Hong; Zhao, Heping; Huang, Yong-Gang

    2018-01-22

    We provide numerical demonstrations of the applicability and accuracy of the quasi-static method and the finite-element method in the investigation of the modifications of the spontaneous emission rate and the energy level shift of an emitter placed near a silver-air interface or a silver nano-sphere. The analytical results are presented as a reference. Our calculations show that the finite element method is an accurate and general method. For frequency away from the radiative mode, the quasi-static method can be applied more effectively for calculating the energy level shift than the spontaneous emission rate. But for frequency around, there is a blue shift for both and this shift increases with the increasing of emitter-silver distance. Applying the theory to the nanosphere dimmer, we see similar phenomenon and find extremely large modifications of the spontaneous emission rate and energy level shift. These findings are instructive in the fields of quantum light-matter interactions.

  4. Characterization of a novel arginine catabolic mobile element (ACME) and staphylococcal chromosomal cassette mec composite island with significant homology to Staphylococcus epidermidis ACME type II in methicillin-resistant Staphylococcus aureus genotype ST22-MRSA-IV.

    LENUS (Irish Health Repository)

    Shore, Anna C

    2011-05-01

    The arginine catabolic mobile element (ACME) is prevalent among methicillin-resistant Staphylococcus aureus (MRSA) isolates of sequence type 8 (ST8) and staphylococcal chromosomal cassette mec (SCCmec) type IVa (USA300) (ST8-MRSA-IVa isolates), and evidence suggests that ACME enhances the ability of ST8-MRSA-IVa to grow and survive on its host. ACME has been identified in a small number of isolates belonging to other MRSA clones but is widespread among coagulase-negative staphylococci (CoNS). This study reports the first description of ACME in two distinct strains of the pandemic ST22-MRSA-IV clone. A total of 238 MRSA isolates recovered in Ireland between 1971 and 2008 were investigated for ACME using a DNA microarray. Twenty-three isolates (9.7%) were ACME positive, and all were either MRSA genotype ST8-MRSA-IVa (7\\/23, 30%) or MRSA genotype ST22-MRSA-IV (16\\/23, 70%). Whole-genome sequencing and comprehensive molecular characterization revealed the presence of a novel 46-kb ACME and staphylococcal chromosomal cassette mec (SCCmec) composite island (ACME\\/SCCmec-CI) in ST22-MRSA-IVh isolates (n=15). This ACME\\/SCCmec-CI consists of a 12-kb DNA region previously identified in ACME type II in S. epidermidis ATCC 12228, a truncated copy of the J1 region of SCCmec type I, and a complete SCCmec type IVh element. The composite island has a novel genetic organization, with ACME located within orfX and SCCmec located downstream of ACME. One PVL locus-positive ST22-MRSA-IVa isolate carried ACME located downstream of SCCmec type IVa, as previously described in ST8-MRSA-IVa. These results suggest that ACME has been acquired by ST22-MRSA-IV on two independent occasions. At least one of these instances may have involved horizontal transfer and recombination events between MRSA and CoNS. The presence of ACME may enhance dissemination of ST22-MRSA-IV, an already successful MRSA clone.

  5. Elaboration of y-fanjasite catalysts containing radioactive elements such as uranyl ion in order to obtain aromatic solvents and heavy amines

    International Nuclear Information System (INIS)

    Nibou, D.

    1990-06-01

    The present work has shown the possibility of ammonia alkylation by n-octanol-l in gaseous phase, in presence of zeolitic catalysts. These catalysts are Y faujasitic types being used in waste water demineralization containing radioactive elements such as uranyl ion. This ion gives to the Y faujasite similar activity and selectivity as those of catalysts containing rare earths or transition metals. Toluene disproportionation has permitted to test beforehand catalysts destined to ammonia alkylation and to compare their mechanism. We have also proved the possibility to produce heavy amines such as tertiary amines which are used as uranium extractant agent. Some zeolites such as ZSM-5, beta, X, A, analcime, HS and Y faujasite type are prepared by hydrothermal synthesis method and characterized by some analysis techniques

  6. [Clinical usefulness of urine-formed elements' information obtained from bacteria detection by flow cytometry method that uses nucleic acid staining].

    Science.gov (United States)

    Nakagawa, Hiroko; Yuno, Tomoji; Itho, Kiichi

    2009-03-01

    Recently, specific detection method for Bacteria, by flow cytometry method using nucleic acid staining, was developed as a function of automated urine formed elements analyzer for routine urine testing. Here, we performed a basic study on this bacteria analysis method. In addition, we also have a comparison among urine sediment analysis, urine Gram staining and urine quantitative cultivation, the conventional methods performed up to now. As a result, the bacteria analysis with flow cytometry method that uses nucleic acid staining was excellent in reproducibility, and higher sensitivity compared with microscopic urinary sediment analysis. Based on the ROC curve analysis, which settled urine culture method as standard, cut-off level of 120/microL was defined and its sensitivity = 85.7%, specificity = 88.2%. In the analysis of scattergram, accompanied with urine culture method, among 90% of rod positive samples, 80% of dots were appeared in the area of 30 degrees from axis X. In addition, one case even indicated that analysis of bacteria by flow cytometry and scattergram of time series analysis might be helpful to trace the progress of causative bacteria therefore the information supposed to be clinically significant. Reporting bacteria information with nucleic acid staining flow cytometry method is expected to contribute to a rapid diagnostics and treatment of urinary tract infections. Besides, the contribution to screening examination of microbiology and clinical chemistry, will deliver a more efficient solution to urine analysis.

  7. Insight on the anisotropic nature of the D'' layer through the analysis of SKS-SKKS splitting obtained via 3D spectral element modeling

    Science.gov (United States)

    Tesoniero, A.; Leng, K.; Long, M. D.; Nissen-Meyer, T.

    2017-12-01

    Constraining the nature of the anisotropy in the core-mantle boundary region is a key factor for properly predicting the flow of the lowermost mantle. The lack of seismic waves sampling this region and their uneven azimuthal distribution hamper a correct representation of mantle dynamics. We present preliminary results for a series of SKS-SKKS splitting analysis based on numerical forward synthetic tests in a realistic 3-D Earth model using the software AXISEM3D, a newly developed efficient hybrid spectral element method solver for 3-D structures. The anisotropic property of the computational domain in the bottom 300km of the Earth's mantle is fully described with a fourth-order elastic tensor with 21 independent coefficients. We tested a single crystal mineralogy of postperovskite with different orientations that are consistent with realistic mantle flow models and accounted for a wide coverage of azimuthal seismic raypaths. We take advantage of the computational efficiency of the method to achieve resolutions for seismic periods as low as 8s. Our preliminary results, based on forward full waveform modeling, represent a step forward for validating hypotheses for the anisotropy in the D'' layer derived by direct splitting measurements and ray-theoretical mineral physics based modeling tests. Our study also highlights the capability of AXISEM3D to handle high degrees of model complexity in full anisotropy and its potentials for future endeavours.

  8. Excision of the Staphylococcal Cassette Chromosome mec (SCCmec) and its crucial role in the horizontal transfer of methicillin resistance in staphylococci.

    OpenAIRE

    Stojanov, M.

    2012-01-01

    Staphylococcus aureus est un pathogène humain majeur ayant développé des résistances contre la quasi totalité des antibiotiques disponibles, incluant la très importante famille des β- lactamines. La résistance à cette classe d'antibiotiques est conférée par la « Staphylococcal Cassette Chromosome mec » (SCCmec), qui est un élément génétique mobile capable de s'insérer dans le chromosome bactérien et capable d'être transféré horizontalement chez d'autres staphylocoques. Le mécanisme moléculair...

  9. Analytical quality assessment and interpretation of the trace element data obtained in the frame of the IAEA Co-ordinated Research Programme on the significance of hair mineral analysis as a means for assessing internal body burdens of environmental pollutants

    International Nuclear Information System (INIS)

    Goeij, J.J.M. de; Blaauw, M.; Zegers, C.

    1993-01-01

    At the request of the IAEA, the authors have performed an assessment of the analytical quality and the interpretation of the trace element data obtained within the framework of the IAEA Co-ordinated Research Programme (CRP) on The Significance of Hair Mineral Analysis as a Means of Assessing Internal Body Burdens of Environmental Pollutants. In this CRP research groups from various countries participated, using different analytical procedures, based on NAA, XRF and AAS. Data have been collected for Zn, CU, Pb, Cd, As, Hg, and Se in male human hair, liver, kidney, lung, brain, and bone. The samples analyzed originated from China, Hungary, Bulgaria, Japan, the former GDR, Sweden and Norway. The analytical quality of the data has been assessed on basis of the calculated limits of quantitation per trace element determined, per tissue analyzed and per participant, as well as from the trace element values found for reference materials and ''blind'' materials. The analytical quality of the data differs widely, from generally good to reasonable (Zn, Cu, and Se) to generally inadequate to strongly inadequate (Pb, Cd, As, and Hg). 15 refs, 29 tabs

  10. Antimicrobial susceptibility pattern and SCCmec types of methicillin-resistant coagulase-negative staphylococci from subclinical bovine mastitis in Hatay, Turkey

    Directory of Open Access Journals (Sweden)

    Aslantaş Özkan

    2014-12-01

    Full Text Available Eighty-nine isolates of coagulase-negative staphylococci (CoNS of eight species from subclinical bovine mastitis were screened for the phenotypic and genotypic methicilline-resistance. In addition, all methicillin-resistant (MR isolates indicating the mecA gene were examined by PCR for the antimicrobial susceptibility patterns, and staphylococcal cassette chromosome mec (SCCmec types were also determined by multiplex PCR. A total of 21 (23.6% CoNS isolates were found to be resistant to oxacillin in broth microdilution assay. All isolates phenotypically resistant to oxacillin did not have the mecA gene, which was only found in 14.6% (13 of the isolates. Most MR-CoNS isolates were highly resistant to erythromycin (92.3%, fusidic acid (84.6%, penicillin (76.9%, and rifampycin (61.5%, and susceptible to mupirocin (100%, tetracycline (100%, vancomycin (100%, clindamycin (92.3%, and sulfamethoxazole-trimethoprim (69.2%. In conclusion, a high rate of antimicrobial resistance among MR-CoNS isolated from food producing animals emphasises the need for periodic surveillance of their resistance.

  11. A Review of Staphylococcal Cassette Chromosome mec (SCCmec) Types in Coagulase-Negative Staphylococci (CoNS) Species.

    Science.gov (United States)

    Saber, Huda; Jasni, Azmiza Syawani; Jamaluddin, Tengku Zetty Maztura Tengku; Ibrahim, Rosni

    2017-10-01

    Coagulase-negative staphylococci (CoNS) are considered low pathogenic organisms. However, they are progressively causing more serious infections with time because they have adapted well to various antibiotics owing to their ability to form biofilms. Few studies have been conducted on CoNS in both, hospital and community-acquired settings, especially in Malaysia. Thus, it is important to study their species and gene distributions. A mobile genetic element, staphylococcal cassette chromosome mec (SCC mec ), plays an important role in staphylococci pathogenesis. Among CoNS, SCC mec has been studied less frequently than Staphylococcus aureus (coagulase-positive staphylococci). A recent study (8) conducted in Malaysia successfully detected SCC mec type I to VIII as well as several new combination patterns in CoNS species, particularly Staphylococcus epidermidis . However, data are still limited, and further research is warranted. This paper provides a review on SCC mec types among CoNS species.

  12. Complete Circular Genome Sequence of Successful ST8/SCCmecIV Community-Associated Methicillin-Resistant Staphylococcus aureus (OC8) in Russia: One-Megabase Genomic Inversion, IS256’s Spread, and Evolution of Russia ST8-IV

    Science.gov (United States)

    Wan, Tsai-Wen; Higuchi, Wataru; Hung, Wei-Chun; Reva, Ivan V.; Singur, Olga A.; Gostev, Vladimir V.; Sidorenko, Sergey V.; Peryanova, Olga V.; Salmina, Alla B.; Reva, Galina V.; Teng, Lee-Jene; Yamamoto, Tatsuo

    2016-01-01

    ST8/SCCmecIV community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been a common threat, with large USA300 epidemics in the United States. The global geographical structure of ST8/SCCmecIV has not yet been fully elucidated. We herein determined the complete circular genome sequence of ST8/SCCmecIVc strain OC8 from Siberian Russia. We found that 36.0% of the genome was inverted relative to USA300. Two IS256, oppositely oriented, at IS256-enriched hot spots were implicated with the one-megabase genomic inversion (MbIN) and vSaβ split. The behavior of IS256 was flexible: its insertion site (att) sequences on the genome and junction sequences of extrachromosomal circular DNA were all divergent, albeit with fixed sizes. A similar multi-IS256 system was detected, even in prevalent ST239 healthcare-associated MRSA in Russia, suggesting IS256’s strong transmission potential and advantage in evolution. Regarding epidemiology, all ST8/SCCmecIVc strains from European, Siberian, and Far Eastern Russia, examined had MbIN, and geographical expansion accompanied divergent spa types and resistance to fluoroquinolones, chloramphenicol, and often rifampicin. Russia ST8/SCCmecIVc has been associated with life-threatening infections such as pneumonia and sepsis in both community and hospital settings. Regarding virulence, the OC8 genome carried a series of toxin and immune evasion genes, a truncated giant surface protein gene, and IS256 insertion adjacent to a pan-regulatory gene. These results suggest that unique single ST8/spa1(t008)/SCCmecIVc CA-MRSA (clade, Russia ST8-IVc) emerged in Russia, and this was followed by large geographical expansion, with MbIN as an epidemiological marker, and fluoroquinolone resistance, multiple virulence factors, and possibly a multi-IS256 system as selective advantages. PMID:27741255

  13. Geochemical characteristics of black shales from the ore-bearing complex of strata of the Male Karpaty Mts. IV. Evaluation of data on the element contents obtained by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cambel, B. (Slovenska Akademia Vied, Bratislava (Czechoslovakia). Geologicky Ustav); Khun, M. (Komenskeho Univ., Bratislava (Czechoslovakia). Prirodovedecka Fakulta)

    1983-06-01

    The application is described of instrumental neutron activation analysis in determining the levels of the individual elements in rocks. Samples were irradiated in the WWR-S reactor at Rez near Prague, and evaluated by the Radiometric Department of the Central Laboratories of the Czechoslovak Uranium Industry. The results are described in detail of measuring the levels of W, Ta, Sc, Hf, Ga, Rb, Cs, U, Th, Au, Sb, As, Zn and Ag in Male Karpaty rocks. The levels of the elements in different samples and in different localities are tabulated. A comparison is made with the Keno Hill, Yukon (USA) area where the polymetallic mineralization is evolutionally analogous to that of the Male Karpaty region.

  14. Microscopical and elemental FESEM and Phenom ProX-SEM-EDS analysis of osteocyte- and blood vessel-like microstructures obtained from fossil vertebrates of the Eocene Messel Pit, Germany.

    Science.gov (United States)

    Cadena, Edwin

    2016-01-01

    The Eocene (∾48 Ma) Messel Pit in Germany is a UNESCO World Heritage Site because of its exceptionally preserved fossils, including vertebrates, invertebrates, and plants. Messel fossil vertebrates are typically characterized by their articulated state, and in some cases the skin, hair, feathers, scales and stomach contents are also preserved. Despite the exceptional macroscopic preservation of Messel fossil vertebrates, the microstructural aspect of these fossils has been poorly explored. In particular, soft tissue structures such as hair or feathers have not been chemically analyzed, nor have bone microstructures. I report here the preservation and recovery of osteocyte-like and blood vessel-like microstructures from the bone of Messel Pit specimens, including the turtles Allaeochelys crassesculpta and Neochelys franzeni, the crocodile Diplocynodon darwini, and the pangolin Eomanis krebsi. I used a Field Emission Scanning Electron Microscope (FESEM) and a Phenom ProX desktop scanning electron microscope (LOT-QuantumDesign) equipped with a thermionic CeB6 source and a high sensitivity multi-mode backscatter electron (BSE) for microscopical and elemental characterization of these bone microstructures. Osteocyte-like and blood vessel-like microstructures are constituted by a thin layer (∾50 nm thickness), external and internal mottled texture with slightly marked striations. Circular to linear marks are common on the external surface of the osteocyte-like microstructures and are interpreted as microbial troughs. Iron (Fe) is the most abundant element found in the osteocyte-like and blood vessel-like microstructures, but not in the bone matrix or collagen fibril-like microstructures. The occurrence of well-preserved soft-tissue elements (at least their physical form) establishes a promising background for future studies on preservation of biomolecules (proteins or DNA) in Messel Pit fossils.

  15. Microscopical and elemental FESEM and Phenom ProX-SEM-EDS analysis of osteocyte- and blood vessel-like microstructures obtained from fossil vertebrates of the Eocene Messel Pit, Germany

    Directory of Open Access Journals (Sweden)

    Edwin Cadena

    2016-01-01

    Full Text Available The Eocene (∾48 Ma Messel Pit in Germany is a UNESCO World Heritage Site because of its exceptionally preserved fossils, including vertebrates, invertebrates, and plants. Messel fossil vertebrates are typically characterized by their articulated state, and in some cases the skin, hair, feathers, scales and stomach contents are also preserved. Despite the exceptional macroscopic preservation of Messel fossil vertebrates, the microstructural aspect of these fossils has been poorly explored. In particular, soft tissue structures such as hair or feathers have not been chemically analyzed, nor have bone microstructures. I report here the preservation and recovery of osteocyte-like and blood vessel-like microstructures from the bone of Messel Pit specimens, including the turtles Allaeochelys crassesculpta and Neochelys franzeni, the crocodile Diplocynodon darwini, and the pangolin Eomanis krebsi. I used a Field Emission Scanning Electron Microscope (FESEM and a Phenom ProX desktop scanning electron microscope (LOT-QuantumDesign equipped with a thermionic CeB6 source and a high sensitivity multi-mode backscatter electron (BSE for microscopical and elemental characterization of these bone microstructures. Osteocyte-like and blood vessel-like microstructures are constituted by a thin layer (∾50 nm thickness, external and internal mottled texture with slightly marked striations. Circular to linear marks are common on the external surface of the osteocyte-like microstructures and are interpreted as microbial troughs. Iron (Fe is the most abundant element found in the osteocyte-like and blood vessel-like microstructures, but not in the bone matrix or collagen fibril-like microstructures. The occurrence of well-preserved soft-tissue elements (at least their physical form establishes a promising background for future studies on preservation of biomolecules (proteins or DNA in Messel Pit fossils.

  16. The effect of the addition of the elements Ni, Zn and Co in a composite AlTiO2 obtained by high-energy milling and sintering process

    International Nuclear Information System (INIS)

    Carvalho, C.O. de; Coelho, R.E.; Conrado, L.C.; Nascimento, C.S.; Teixeira, C.A.; Mendonca, E.S.

    2016-01-01

    The present work use aluminum scrap with addition of TiO 2 , Ni, Zn or Co to preparation and characterization of nanocomposites. The aluminum were cut and subjected to high energy milling for 2 hours at 1200rpm. The obtained powder was added to TiO 2 , Ni, Zn or Co in a nominal composition 97Al-2TiO 2 -1X (X = Ni, Zn or Co) (weight %) and again, the mixture was subjected to milling for 1 hour at 1000rpm. Grinding powders were hot pressed in the closed die and then removed; the compressed were sintered at 950°C in a tubular furnace N 2 passing atmosphere. The samples obtained were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD). The results of SEM images showed a very refined microstructure and an aluminum matrix without porosity. (author)

  17. Obtaining of inulin acetate

    OpenAIRE

    Khusenov, Arslonnazar; Rakhmanberdiev, Gappar; Rakhimov, Dilshod; Khalikov, Muzaffar

    2014-01-01

    In the article first obtained inulin ester inulin acetate, by etherification of inulin with acetic anhydride has been exposed. Obtained product has been studied using elementary analysis and IR spectroscopy.

  18. Technology for obtaining of solar elements based on heterostructure basis

    International Nuclear Information System (INIS)

    Camalova, A.Q.; Aliyeva, A.K.; Zeynalova, S.M.; Latifova, N.A.

    2013-01-01

    As it is known the level of energy sources usage reflects the level of development of civilization and was accepted by all as main factor. Currently, there are mainly oil, coal and natural gas are used as raw material in traditional energy, which leads to formation of environmental problems. They are not endless reserves of traditional energy sources and there is a danger of their extinction in the near future. For that reason, recently, the use of wind, solar, thermal waters and some other natural resources rapidly increased in many countries. The most important place among these natural resources belongs to solar energy. Thus, the amount of solar energy coming into the earth is much more than the amount of energy of oil, gas, coal and uranium reserves in the world taken together. At present the annual production of solar components exceeds 500 MW in the world. Photoelectric stations are silent and do not waste harmful products to the environment. The majority of modern solar cells are made on the basis of a single p-n junction

  19. Standard elements; Elements standards

    Energy Technology Data Exchange (ETDEWEB)

    Blanc, B [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Following his own experience the author recalls the various advantages, especially in the laboratory, of having pre-fabricated vacuum-line components at his disposal. (author) [French] A la suite de sa propre experience, l'auteur veut rappeler les divers avantages que presente, tout particulierement en laboratoire, le fait d'avoir a sa disposition des elements pre-fabriques de canalisations a vide. (auteur)

  20. Identification of a PVL-negative SCCmec-IVa sub-lineage of the methicillin-resistant Staphylococcus aureus CC80 lineage

    DEFF Research Database (Denmark)

    Edslev, Sofie Marie; Westh, Henrik Torkil; Andersen, Paal Skytt

    2018-01-01

    of the CC80 S. aureus lineage was conducted from whole-genome sequences of 217 isolates (23 MSSA and 194 MRSA) from 22 countries. All isolates were further genetically characterized in regard to resistance determinants and PVL carriage, and epidemiological data was obtained for selected isolates. RESULTS....... CONCLUSIONS: This study reports the emergence of a novel CC80 CA-MRSA sub-lineage, showing that the CC80 lineage is more diverse than previously assumed....

  1. Galvanic element. Galvanisches Element

    Energy Technology Data Exchange (ETDEWEB)

    Sprengel, D.; Haelbig, H.

    1980-01-03

    The invention concerns a gas-tight sealed accumulator with positive and negative electrode plates and an auxillary electrode electroconductively bound to the latter for suppressing oxygen pressure. The auxillary electrode is an intermediate film electrode. The film catalysing oxygen reduction is hydrophilic in character and the other film is hydrophobic. A double coated foil has proved to be advantageous, the hydrophilic film being formed from polymer-bound activated carbon and the hydrophrobic film from porous polytetrafluoroethylene. A metallic network of silver or nickel is rolled into the outer side of the activated carbon film. This auxillary electrode can be used to advantage in all galvanic elements. Even primary cells fall within the scope of application for auxillary electrodes because many of these contain a highly oxidized electrodic material which tends to give off oxygen.

  2. Superheavy elements

    CERN Document Server

    Hofmann, S

    1999-01-01

    The outstanding aim of experimental investigations of heavy nuclei is the exploration of spherical 'SuperHeavy Elements' (SHEs). On the basis of the nuclear shell model, the next double magic shell-closure beyond sup 2 sup 0 sup 8 Pb is predicted at proton numbers between Z=114 and 126 and at neutron number N=184. All experimental efforts aiming at identifying SHEs (Z>=114) were negative so far. A highly sensitive search experiment was performed in November-December 1995 at SHIP. The isotope sup 2 sup 9 sup 0 116 produced by 'radiative capture' was searched for in the course of a 33 days irradiation of a sup 2 sup 0 sup 8 Pb target with sup 8 sup 2 Se projectiles, however, only cross-section limits were measured. Positive results were obtained in experiments searching for elements from 110 to 112 using cold fusion and the 1n evaporation channel. The produced isotopes were unambiguously identified by means of alpha-alpha correlations. Not fission, but alpha emission is the dominant decay mode. The measurement ...

  3. Fuel element

    International Nuclear Information System (INIS)

    Hirose, Yasuo.

    1982-01-01

    Purpose: To increase the plenum space in a fuel element used for a liquid metal cooled reactor. Constitution: A fuel pellet is secured at one end with an end plug and at the other with a coil spring in a tubular container. A mechanism for fixing the coil spring composed of a tubular unit is mounted by friction with the inner surface of the tubular container. Accordingly, the recoiling force of the coil spring can be retained by fixing mechanism with a small volume, and since a large amount of plenum space can be obtained, the internal pressure rise in the cladding tube can be suppressed even if large quantities of fission products are discharged. (Kamimura, M.)

  4. Seagrass leaf element content

    NARCIS (Netherlands)

    Vonk, J.A.; Smulders, Fee O.H.; Christianen, Marjolijn J.A.; Govers, Laura L.

    2017-01-01

    Knowledge on the role of seagrass leaf elements and in particular micronutrients and their ranges is limited. We present a global database, consisting of 1126 unique leaf values for ten elements, obtained from literature and unpublished data, spanning 25 different seagrass species from 28 countries.

  5. Limitless Analytic Elements

    Science.gov (United States)

    Strack, O. D. L.

    2018-02-01

    We present equations for new limitless analytic line elements. These elements possess a virtually unlimited number of degrees of freedom. We apply these new limitless analytic elements to head-specified boundaries and to problems with inhomogeneities in hydraulic conductivity. Applications of these new analytic elements to practical problems involving head-specified boundaries require the solution of a very large number of equations. To make the new elements useful in practice, an efficient iterative scheme is required. We present an improved version of the scheme presented by Bandilla et al. (2007), based on the application of Cauchy integrals. The limitless analytic elements are useful when modeling strings of elements, rivers for example, where local conditions are difficult to model, e.g., when a well is close to a river. The solution of such problems is facilitated by increasing the order of the elements to obtain a good solution. This makes it unnecessary to resort to dividing the element in question into many smaller elements to obtain a satisfactory solution.

  6. Stability of superheavy elements around Z=120 probed by the study of their fission time obtained by the crystal blocking method; Stabilite d'elements superlourds au voisinage de Z=120 testee par l'etude de leurs temps de fission deduits par la methode du blocage cristallin

    Energy Technology Data Exchange (ETDEWEB)

    Laget, M

    2007-10-15

    While the existence of an island of stability beyond Z=110 is theoretically acquired, the location of this island ranges from Z=114 to Z=126 depending on models. In this work, the stability of super-heavy nuclei is probed through the study of their fission time. The chosen experimental method, the crystal blocking method, is sensitive to the presence of possible long time components in the fission time distribution which indicates a fission mechanism occurring after the formation of a compound nucleus. The blocking dips were therefore constituted for the various products of the reaction U{sup 238} + Ni (6.6 MeV/A) {yields} 120, the experimental set-up allowing us to clearly identify and select the reaction mechanisms. The comparison of the blocking dip constituted for quasi-elastic scattering events with the one obtained for the fission fragments of a Z=120, combined with the study of kinematical properties of these fission fragments, give evidences of the existence of very long fission times (> 10{sup -18} s) only compatible with a fusion-fission mechanism implying a non vanishing fission barrier height for Z=120. The second part outlines microscopic calculations of fission barrier heights, carried out in the framework of the finite temperature of the Hartree-Fock-Bogoliubov (HFB) theory. Because of the progressive vanishing of the pairing correlation with T, which happens differently at the ground state and at the top of the barrier, B{sub f} first grows until T {approx_equal} 0.8 MeV before dropping with T owing to shell-effects damping with temperature. (author)

  7. Molecular characteristics of clinical methicillin-resistant Staphylococcus pseudintermedius harboring arginine catabolic mobile element (ACME) from dogs and cats.

    Science.gov (United States)

    Yang, Ching; Wan, Min-Tao; Lauderdale, Tsai-Ling; Yeh, Kuang-Sheng; Chen, Charles; Hsiao, Yun-Hsia; Chou, Chin-Cheng

    2017-06-01

    This study aimed to investigate the presence of arginine catabolic mobile element (ACME) and its associated molecular characteristics in methicillin-resistant Staphylococcus pseudintermedius (MRSP). Among the 72 S. pseudintermedius recovered from various infection sites of dogs and cats, 52 (72.2%) were MRSP. ACME-arcA was detected commonly (69.2%) in these MRSP isolates, and was more frequently detected in those from the skin than from other body sites (P=0.047). There was a wide genetic diversity among the ACME-arcA-positive MRSP isolates, which comprised three SCCmec types (II-III, III and V) and 15 dru types with two predominant clusters (9a and 11a). Most MRSP isolates were multidrug-resistant. Since S. pseudintermedius could serve as a reservoir of ACME, further research on this putative virulence factor is recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Panton-Valentine Leukocidin, SCCmec p

    African Journals Online (AJOL)

    (DOAJ), African Journal Online, Bioline International, Open-J-Gate and Pharmacy Abstracts. INTRODUCTION ..... restaurant food samples in Malaysia were infected with S. .... resistant Staphylococcus aureus (MRSA) on retail meat in Iowa.

  9. Transplutonium elements

    Energy Technology Data Exchange (ETDEWEB)

    Sivaramakrishnan, C. K.; Jadhav, A. V.; Reghuraman, K.; Mathew, K. A.; Nair, P. S.; Ramaniah, M. V.

    1973-07-01

    Research progress is reported on studies of the transplutonium elements including recovery and purification of americium, preparation of /sup 238/Pu, extraction studies using diethylhexyl phosphate. (DHM)

  10. Toxic Elements

    DEFF Research Database (Denmark)

    Hajeb, Parvaneh; Shakibazadeh, Shahram; Sloth, Jens Jørgen

    2016-01-01

    Food is considered the main source of toxic element (arsenic, cadmium, lead, and mercury) exposure to humans, and they can cause major public health effects. In this chapter, we discuss the most important sources for toxic element in food and the foodstuffs which are significant contributors to h...

  11. Fuel element

    International Nuclear Information System (INIS)

    Armijo, J.S.

    1976-01-01

    A fuel element for nuclear reactors is proposed which has a higher corrosion resisting quality in reactor operations. The zirconium alloy coating around the fuel element (uranium or plutonium compound) has on its inside a protection layer of metal which is metallurgically bound to the substance of the coating. As materials are namned: Alluminium, copper, niobium, stainless steel, and iron. This protective metallic layer has another inner layer, also metallurgically bound to its surface, which consists usually of a zirconium alloy. (UWI) [de

  12. PELTIER ELEMENTS

    CERN Document Server

    Tani, Laurits

    2015-01-01

    To control Peltier elements, temperature controller was used. I used TEC-1091 that was manufactured my Meerstetter Engineering. To gain control with the temperature controller, software had to be intalled on a controlling PC. There were different modes to control the Peltier: Tempererature controller to control temperature, Static current/voltage to control voltage and current and LIVE ON/OFF to auto-tune the controller respectively to the system. Also, since near the collision pipe there is much radiation, radiation-proof Peltier elements have to be used. To gain the best results, I had to find the most efficient Peltier elements and try to get their cold side to -40 degrees Celsius.

  13. Devices for obtaining information about radiation sources

    International Nuclear Information System (INIS)

    Tosswill, C.H.

    1981-01-01

    The invention provides a sensitive, fast high-resolution device for obtaining information about the distribution of gamma and X-radiation sources and provides a radiation detector useful in such a device. It comprises a slit collimator with a multiplicity of slits each with slit-defining walls of material and thickness to absorb beam components impinging on them. The slits extend further in one direction than the other. The detector for separately detecting beam components passing through the slits also provides data output signals. It comprises a plurality of radiation transducing portions which are not photoconductor elements each at the end of a slit. A positioner operates to change the transverse position of the slits and radiation transducing portions relative to the source, wherein each radiation transducing element is positioned within its respective slit between the slit defining walls. Full details and preferred embodiments are given. (U.K.)

  14. Fuel element

    International Nuclear Information System (INIS)

    Kennedy, S.T.

    1982-01-01

    A nuclear reactor fuel element wherein a stack of nuclear fuel is prevented from displacement within its sheath by a retainer comprising a tube member which is radially expanded into frictional contact with the sheath by means of a captive ball within a tapered bore. (author)

  15. Transactinide elements

    International Nuclear Information System (INIS)

    Hemingway, J.D.

    1975-01-01

    The review is covered in sections, entitled: predicted nuclear properties - including closed shells, decay characteristics; predicted chemical properties - including electronic structure and calculated properties, X-radiation, extrapolated chemical properties, separation chemistry; methods of synthesis; the natural occurrence of superheavy elements. (U.K.)

  16. New elements

    International Nuclear Information System (INIS)

    Flerov, G.

    1976-01-01

    The history is briefly described of the investigation of superheavy elements at the Joint Institute for Nuclear Research at Dubna. The significance of the investigation is assessed from the point of view of the nuclear structure study and major problems encountered in experimental efforts are indicated. Current experimental methods aiming at the discovery or the production of superheavy nuclei with Z approximately 114 are listed. (I.W.)

  17. Superconductive ceramics obtained with sol gel method

    International Nuclear Information System (INIS)

    Arcangeli, A.; Mosci, A.; Nardi, A.; Vatteroni, R.; Zondini, C.

    1988-01-01

    Several sol gel routes have been considered, studied and developed to produce large quantities of granulates which can be processed to obtain ceramics having good superconducting characteristics. In the considered process a mixture of commercial nitrates is atomized, at room temperature, in a solution 1:1 of Primene JMT and Benzene and a pale blue gel of the starting elements is suddently formed. The granulates obtained are free flowing, very reactive and well suited for pressing. For their intrinsic characteristics they could be very good precursors for the production of large quantities of superconductive ceramics in different forms. The precipitated gel is dried, calcinated, pressed in the form of cylindrical pellets which are sintered up to 960 degrees C. No griding or different thermal treatments are needed. The sintered material has low electric resistence, shows a clear Meissner effect and has a transition temperature of between 91 and 95 K

  18. Acoustic barriers obtained from industrial wastes.

    Science.gov (United States)

    Garcia-Valles, M; Avila, G; Martinez, S; Terradas, R; Nogués, J M

    2008-07-01

    Acoustic pollution is an environmental problem that is becoming increasingly more important in our society. Likewise, the accumulation of generated waste and the need for waste management are also becoming more and more pressing. In this study we describe a new material--called PROUSO--obtained from industrial wastes. PROUSO has a variety of commercial and engineering, as well as building, applications. The main raw materials used for this environmentally friendly material come from slag from the aluminium recycling process, dust from the marble industry, foundry sands, and recycled expanded polystyrene from recycled packaging. Some natural materials, such as plastic clays, are also used. To obtain PROUSO we used a conventional ceramic process, forming new mineral phases and incorporating polluted elements into the structure. Its physical properties make PROUSO an excellent acoustic and thermal insulation material. It absorbs 95% of the sound in the frequency band of the 500 Hz. Its compressive strength makes it ideal for use in ceramic wall building.

  19. Radiographic element

    International Nuclear Information System (INIS)

    Abbott, T.I.; Jones, C.G.

    1984-01-01

    Radiographic elements are disclosed comprised of first and second silver halide emulsion layers separated by an interposed support capable of transmitting radiation to which the second image portion is responsive. At least the first imaging portion contains a silver halide emulsion in which thin tubular silver halide grains of intermediate aspect ratios (from 5:1 to 8:1) are present. Spectral sensitizing dye is adsorbed to the surface of the tubular grains. Increased photographic speeds can be realized at comparable levels of crossover. (author)

  20. Experimental results obtained at GANIL

    International Nuclear Information System (INIS)

    Borrel, V.

    1993-01-01

    A review of experimental results obtained at GANIL on the study of nuclear structure and nuclear reactions with secondary radioactive beams is presented. Mass measurements by means of the GANIL cyclotrons are described. The possibilities of GANIL/LISE3 for the production and separation of radioactive beams are illustrated through a large variety of experiments. (author). 19 refs., 8 figs

  1. Geopolymer obtained from coal ash

    International Nuclear Information System (INIS)

    Conte, V.; Bissari, E.S.; Uggioni, E.; Bernardin, A.M.

    2011-01-01

    Geopolymers are three-dimensional alumino silicates that can be rapidly formed at low temperature from naturally occurring aluminosilicates with a structure similar to zeolites. In this work coal ash (Tractebel Energy) was used as source of aluminosilicate according a full factorial design in eight formulations with three factors (hydroxide type and concentration and temperature) and two-levels. The ash was dried and hydroxide was added according type and concentration. The geopolymer was poured into cylindrical molds, cured (14 days) and subjected to compression test. The coal ash from power plants belongs to the Si-Al system and thus can easily form geopolymers. The compression tests showed that it is possible to obtain samples with strength comparable to conventional Portland cement. As a result, temperature and molarity are the main factors affecting the compressive strength of the obtained geopolymer. (author)

  2. Truncated States Obtained by Iteration

    International Nuclear Information System (INIS)

    Cardoso, W. B.; Almeida, N. G. de

    2008-01-01

    We introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST

  3. Obtaining zircaloy powder through hydriding

    International Nuclear Information System (INIS)

    Dupim, Ivaldete da Silva; Moreira, Joao M.L.

    2009-01-01

    Zirconium alloys are good options for the metal matrix in dispersion fuels for power reactors due to their low thermal neutron absorption cross-section, good corrosion resistance, good mechanical strength and high thermal conductivity. A necessary step for obtaining such fuels is producing Zr alloy powder for the metal matrix composite material. This article presents results from the Zircaloy-4 hydrogenation tests with the purpose to embrittle the alloy as a first step for comminuting. Several hydrogenation tests were performed and studied through thermogravimetric analysis. They included H 2 pressures of 25 and 50 kPa and temperatures ranging between from 20 to 670 deg C. X-ray diffraction analysis showed in the hydrogenated samples the predominant presence of ZrH 2 and some ZrO 2 . Some kinetics parameters for the Zircaloy-4 hydrogenation reaction were obtained: the time required to reach the equilibrium state at the dwell temperature was about 100 minutes; the hydrogenation rate during the heating process from 20 to 670 deg C was about 21 mg/h, and at constant temperature of 670 deg C, the hydride rate was about 1.15 mg/h. The hydrogenation rate is largest during the heating process and most of it occurs during this period. After hydrogenated, the samples could easily be comminuted indicating that this is a possible technology to obtain Zircaloy powder. The results show that only few minutes of hydrogenation are necessary to reach the hydride levels required for comminuting the Zircaloy. The final hydride stoichiometry was between 2.7 and 2.8 H for each Zr atom in the sample (author)

  4. Using small XML elements to support relevance

    NARCIS (Netherlands)

    G. Ramirez Camps (Georgina); T.H.W. Westerveld (Thijs); A.P. de Vries (Arjen)

    2006-01-01

    htmlabstractSmall XML elements are often estimated relevant by the retrieval model but they are not desirable retrieval units. This paper presents a generic model that exploits the information obtained from small elements. We identify relationships between small and relevant elements and use this

  5. Drugs obtained by biotechnology processing

    Directory of Open Access Journals (Sweden)

    Hugo Almeida

    2011-06-01

    Full Text Available In recent years, the number of drugs of biotechnological origin available for many different diseases has increased exponentially, including different types of cancer, diabetes mellitus, infectious diseases (e.g. AIDS Virus / HIV as well as cardiovascular, neurological, respiratory, and autoimmune diseases, among others. The pharmaceutical industry has used different technologies to obtain new and promising active ingredients, as exemplified by the fermentation technique, recombinant DNA technique and the hybridoma technique. The expiry of the patents of the first drugs of biotechnological origin and the consequent emergence of biosimilar products, have posed various questions to health authorities worldwide regarding the definition, framework, and requirements for authorization to market such products.Nos últimos anos, tem aumentado exponencialmente o número de fármacos de origem biotecnológica ao dispor das mais diversas patologias, entre elas destacam-se, os diferentes tipos de cancêr, as doenças infecciosas (ex. vírus AIDS/HIV, as doenças autoimunes, as doenças cardiovasculares, a Diabetes Mellitus, as doenças neurológicas, as doenças respiratórias, entre outras. A indústria farmacêutica tem recorrido a diferentes tecnologias para a obtenção de novos e promissores princípios ativos, como são exemplo a fermentação, a técnica de DNA Recombinante, a técnica de hidridoma, entre outras. A queda das patentes dos primeiros fármacos de origem biotecnológica e o consequente aparecimento dos produtos biossimilares têm colocado diferentes questões às autoridades de saúde mundiais, sobre a definição, enquadramento e exigências para a autorização de entrada no mercado deste tipo de produtos.

  6. The effect of the addition of the elements Ni, Zn and Co in a composite AlTiO{sub 2} obtained by high-energy milling and sintering process; Efeito da adicao dos elementos Ni, Zn ou Co no composito AlTiO{sub 2} obtido por moagem de alta energia e sinterizacao

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, C.O. de; Coelho, R.E.; Conrado, L.C.; Nascimento, C.S.; Teixeira, C.A.; Mendonca, E.S., E-mail: cristiane.olv.carvalho@hotmail.com [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), BA (Brazil)

    2016-07-01

    The present work use aluminum scrap with addition of TiO{sub 2}, Ni, Zn or Co to preparation and characterization of nanocomposites. The aluminum were cut and subjected to high energy milling for 2 hours at 1200rpm. The obtained powder was added to TiO{sub 2}, Ni, Zn or Co in a nominal composition 97Al-2TiO{sub 2}-1X (X = Ni, Zn or Co) (weight %) and again, the mixture was subjected to milling for 1 hour at 1000rpm. Grinding powders were hot pressed in the closed die and then removed; the compressed were sintered at 950°C in a tubular furnace N{sub 2} passing atmosphere. The samples obtained were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD). The results of SEM images showed a very refined microstructure and an aluminum matrix without porosity. (author)

  7. Chemistry of the heaviest elements

    International Nuclear Information System (INIS)

    Schaedel, M.

    1992-08-01

    The experimentally known chemical properties of elements 103,104, and 105, and the experimental techniques to obtain these properties on a one-atom- at-a-time base, are summarized. The chemical properties are compared with the lighter group 3,4 and 5 homologs and with the expected behaviour as obtained from theoretical calculations. In this transition region from the last actinide element to the beginning of the transactinide series one may expect to find evidence for increasingly strong relativistic effects altering the chemical behaviour. (orig.)

  8. Distribution of Staphylococcal cassette chromosome mec Types and correlation with comorbidity and infection type in patients with MRSA bacteremia.

    Directory of Open Access Journals (Sweden)

    Jiun-Ling Wang

    Full Text Available BACKGROUND: Molecular epidemiological definitions that are based on staphylococcal cassette chromosome mec (SCCmec typing and phylogenetic analysis of methicillin-resistant Staphylococcus aureus (MRSA isolates are considered a reliable way to distinguish between healthcare-associated MRSA (HA-MRSA and community-associated MRSA (CA-MRSA. However, there is little information regarding the clinical features and outcomes of bacteremia patients with MRSA carrying different SCCmec types. METHODS: From January 1 through December 31, 2006, we recorded the demographic data and outcomes of 159 consecutive adult MRSA bacteremia patients from whom isolates for SCCmec analysis were collected. All participants were patients at a tertiary care center in Taiwan. PRINCIPAL FINDINGS: The following SCCmec types were identified in MRSA isolates: 30 SCCmec II (18.9%, 87 SCCmec III (54.7%, 22 SCCmec IV (13.8%, and 20 SCCmec V (12.6%. The time from admission to the first MRSA-positive blood culture for patients infected with isolates with the SCCmec III element (mean/median, 50.7/26 days was significantly longer than for patients infected with isolates carrying SCCmec IV or V (mean/median, 6.7/3 days for SCCmec IV; 11.1/10.5 days for SCCmec V (P<0.05. In univariate analysis, community onset, soft tissue infection, and deep-seated infection were predictors for SCCmec IV/V. In multivariate analysis, length of stay before index culture, diabetes mellitus, and being bedridden were independent risk factors associated with SCCmec II/III. CONCLUSIONS: These findings are in agreement with previous studies of the genetic characteristics of CA-MRSA. MRSA bacteremia with SCCmec II/III isolates occurred more among patients with serious comorbidities and prolonged hospitalization. Community onset, skin and soft tissue infection, and deep-seated infection best predicted SCCmec IV/V MRSA bacteremia.

  9. Elemental balance in soy sauce

    International Nuclear Information System (INIS)

    Haruyama, Yoichi; Saito, Manabu; Yoshida, Koji.

    1996-01-01

    We have measured the elemental concentrations of soy sauce and its actual raw materials which are used in a certain soy sauce factory. In the present measurement, we measured de-fatted soybean, wheat and salt as raw materials and soy sauce and soy sauce waste as final products. Five kinds of elements, such as Mn, Fe, Cu, Zn and Br, were detected. We obtained elemental concentrations of them except for Mn in each materials. The measured elemental concentration in soy sauce agreed well each other with the calculated one within the experimental errors using the measured concentration in the raw materials and their weight in actual producing process. Contrary to our expectation, it was found that wheat contributes to soy sauce bromine concentration dominantly in the present case. (author)

  10. Chemistry of the heaviest elements

    International Nuclear Information System (INIS)

    Hoffman, D.C.

    1996-01-01

    Studies of the chemical properties of the elements at the uppermost end of the periodic table are discussed. Some historical perspective is given, but major emphasis is on recent studies. Isotopes of these elements are short-lived and, therefore, must be studied near the site of production. They must be produced with charged-particle beams at accelerators rather than via neutron capture. The use of radioactive heavy actinide targets is often required and the number of atoms produced is so small that any chemistry to be performed must be done on an ''atom-at-a-time'' basis. Furthermore, a knowledge of their nuclear properties is required in order to identify and detect them. To date, both gas and aqueous phase properties of elements as heavy as element 104 (rutherfordium) and element 105 (hahnium) have been investigated, even though their longest-lived known isotopes have half-lives of only 65 and 35 seconds, respectively. The experimental results show that their chemical properties cannot be simply extrapolated from the known properties of their lighter homologs in the periodic table, emphasizing the importance of obtaining additional experimental information for the heaviest elements to compare with predictions and help assess the influence of relativistic effects. The feasibility of the extension of chemical studies to still heavier elements is also discussed. (orig.)

  11. Process for obtaining oxygen doped zinc telluride monocrystals and scintillator crystals obtained by this process

    International Nuclear Information System (INIS)

    Schneider, Maurice; Moreau, Roland; D'Haenen, J.-P.; Merenda, Pierre.

    1976-01-01

    A process is described for obtaining oxygen doped zinc telluride monocrystals, for use as scintillator crystals for ionising radiation detectors. The following operations are carried out in succession: one or several zinc telluride crystals are introduced into a silica ampoule together with a ternary mixture of zinc tellurium and oxygen, as an oxide or hydroxide of these elements; the ampoule is pumped down to a high vacuum and sealed; the sealed ampoule containing the mixture and monocrystals is placed in a kiln and brought to a uniform temperature sufficient to make the mixture three-phased, depending on its composition; the zinc telluride crystalline compound remains solid; the ampoule is then tempered to bring it quickly back to ambient temperature [fr

  12. Discrete Element Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Morris, J; Johnson, S

    2007-12-03

    The Distinct Element Method (also frequently referred to as the Discrete Element Method) (DEM) is a Lagrangian numerical technique where the computational domain consists of discrete solid elements which interact via compliant contacts. This can be contrasted with Finite Element Methods where the computational domain is assumed to represent a continuum (although many modern implementations of the FEM can accommodate some Distinct Element capabilities). Often the terms Discrete Element Method and Distinct Element Method are used interchangeably in the literature, although Cundall and Hart (1992) suggested that Discrete Element Methods should be a more inclusive term covering Distinct Element Methods, Displacement Discontinuity Analysis and Modal Methods. In this work, DEM specifically refers to the Distinct Element Method, where the discrete elements interact via compliant contacts, in contrast with Displacement Discontinuity Analysis where the contacts are rigid and all compliance is taken up by the adjacent intact material.

  13. Probabilistic fracture finite elements

    Science.gov (United States)

    Liu, W. K.; Belytschko, T.; Lua, Y. J.

    1991-05-01

    The Probabilistic Fracture Mechanics (PFM) is a promising method for estimating the fatigue life and inspection cycles for mechanical and structural components. The Probability Finite Element Method (PFEM), which is based on second moment analysis, has proved to be a promising, practical approach to handle problems with uncertainties. As the PFEM provides a powerful computational tool to determine first and second moment of random parameters, the second moment reliability method can be easily combined with PFEM to obtain measures of the reliability of the structural system. The method is also being applied to fatigue crack growth. Uncertainties in the material properties of advanced materials such as polycrystalline alloys, ceramics, and composites are commonly observed from experimental tests. This is mainly attributed to intrinsic microcracks, which are randomly distributed as a result of the applied load and the residual stress.

  14. Chemistry of the transactinide elements

    International Nuclear Information System (INIS)

    Schaedel, M.

    1995-01-01

    The experimentally known chemical properties of the transactinide elements 104 and 105, and the experimental techniques used to study these properties on an atom-at-a-time base, are reviewed. The production of transactinides in heavy ion reactions and the specific aspects of chemical separations with single atoms is briefly discussed. The chemical properties of the first two transactinide elements are compared with the lighter element homologs in group 4 and 5 of the Periodic Table and with the expected behaviour obtained from most recent atomic and molecular calculations which take the increasingly strong relativistic effect into account. Elements 104 and 105 behave as transactinide elements and, in general, exhibit properties characteristic of their position in group 4 and 5 of the Periodic Table. However, surprising deviations of the chemical properties from expectations based on simple extrapolations have been observed. It is shown that the chemical properties of the heaviest elements cannot reliably be predicted by simple extrapolations. Prospects to extend our chemical knowledge at the top end of the Periodic Table are discussed. (orig.)

  15. Chemistry of the elements

    International Nuclear Information System (INIS)

    Greenwood, N.N.; Earnshaw, A.

    1984-01-01

    This textbook presents an account of the chemistry of the elements for both undergraduate and postgraduate students. It covers not only the 'inorganic' chemistry of the elements, but also analytical, theoretical, industrial, organometallic;, bio-inorganic and other areas of chemistry which apply. The following elements of special nuclear interest are included: Rb, Cs, Fr, Sr, Ba, Ra, Po, At, Rn, Sc, Y, Zr, Hf, V, Nb, Ta, Mo, Tc, Ru, the Lanthanide Elements, the Actinide Elements. (U.K.)

  16. Diffractometric method for obtaining of x-ray diffraction patterns of transplutonium element compounds

    International Nuclear Information System (INIS)

    Dubasov, Yu.V.; Aleksandrov, B.M.; Baranov, Yu.I.; Golubev, V.A.; Nikolaev, V.B.

    1986-01-01

    Method allowing to carry out X-ray radiographic investigations of powders of high radioactive α-sources (transuranium and transplutonium compounds) by the diffractometric method have been developed. The method is tested for three americium compounds crystallizing in different syngonies - dioxide, formiate, oxalate. The substance quantity necessary for analysis is 0.5-1 mg. The investigations can be carried out with diffractometers of general purpose of DRON-UMI and DRON-20 types

  17. The influence of random element displacement on DOA estimates obtained with (Khatri-Rao-)root-MUSIC.

    Science.gov (United States)

    Inghelbrecht, Veronique; Verhaevert, Jo; van Hecke, Tanja; Rogier, Hendrik

    2014-11-11

    Although a wide range of direction of arrival (DOA) estimation algorithms has been described for a diverse range of array configurations, no specific stochastic analysis framework has been established to assess the probability density function of the error on DOA estimates due to random errors in the array geometry. Therefore, we propose a stochastic collocation method that relies on a generalized polynomial chaos expansion to connect the statistical distribution of random position errors to the resulting distribution of the DOA estimates. We apply this technique to the conventional root-MUSIC and the Khatri-Rao-root-MUSIC methods. According to Monte-Carlo simulations, this novel approach yields a speedup by a factor of more than 100 in terms of CPU-time for a one-dimensional case and by a factor of 56 for a two-dimensional case.

  18. MODERATOR ELEMENTS FOR UNIFORM POWER NUCLEAR REACTOR

    Science.gov (United States)

    Balent, R.

    1963-03-12

    This patent describes a method of obtaining a flatter flux and more uniform power generation across the core of a nuclear reactor. The method comprises using moderator elements having differing moderating strength. The elements have an increasing amount of the better moderating material as a function of radial and/or axial distance from the reactor core center. (AEC)

  19. On elastic structural elements for nuclear reactors

    International Nuclear Information System (INIS)

    Povolo, F.

    1978-03-01

    The in-pile stress-relaxation behaviour of materials usually employed for the elastic structural elements, in nuclear reactors, is critically reviewed and the results are compared with those obtained in commercial zirconium alloys irradiated under similar conditions. Finally, it is shown that, under certain conditions, some zirconium alloys may be used as an alternative material for these structural elements. (orig.) [de

  20. Structural elements for fast-neutron reactors

    International Nuclear Information System (INIS)

    Blin, J.C.; Sainfort, Gerard; Silvent, Alain; Silvestres, Georges.

    1974-01-01

    These elements are characterized in that they are obtained from a nickel-alloy and at least a material M, selected from the group comprising iron and silicon, in proportions, by weight, such that irradiation by fast neutrons leads to the generation of Ni 3 -M with no noticeable swelling of said elements. This can be applied to fuel assembly cladding [fr

  1. [Trace elements of bone tumors].

    Science.gov (United States)

    Kalashnikov, V M; Zaĭchik, V E; Bizer, V A

    1983-01-01

    Due to activation analysis involving the use of neutrons from a nuclear reactor, the concentrations of 11 trace elements: scandium, iron, cobalt, mercury, rubidium, selenium, silver, antimony, chrome, zinc and terbium in intact bone and skeletal tumors were measured. 76 specimens of bioptates and resected material of operations for bone tumors and 10 specimens of normal bone tissue obtained in autopsies of cases of sudden death were examined. The concentrations of trace elements and their dispersion patterns in tumor tissue were found to be significantly higher than those in normal bone tissue. Also, the concentrations of some trace elements in tumor differed significantly from those in normal tissue; moreover, they were found to depend on the type and histogenesis of the neoplasm.

  2. Marine oligotrophy and element biogeochemistry

    International Nuclear Information System (INIS)

    Jeffree, R.A.; Szymczak, R.

    1999-01-01

    A biogeochemical model has been developed that explains the inverse and non-linear relationship between Po-210 concentration in zooplankton and their biomass, under oligotrophic conditions in French Polynesia. This study identified other elements with comparable accumulatory behaviours to Po-210 in phytoplankton, seston and zooplankton, that are proposed to be critical to its enhanced environmental levels under oligotrophy. Field investigation in the Gulf of Papua showed that four of these a priori identified elements viz Cd, Co, Pb and Mn, as well as Cr and Ni, showed elevated water concentrations with reduced biological productivity, results that are consistent with those previously obtained for Po-210 and the proposed explanatory model. These findings point to the enhanced susceptibility of oligotrophic systems to contamination from particle-reactive elements. (author)

  3. A CAREM type fuel element dynamic analysis

    International Nuclear Information System (INIS)

    Magoia, J.E.

    1990-01-01

    A first analysis on the dynamic behaviour of a fuel element designed for the CAREM nuclear reactor (Central Argentina de Elementos Modulares) was performed. The model used to represent this dynamic behaviour was satisfactorily evaluated. Using primary estimations for some of its numerical parameters, a first approximation to its natural vibrational modes was obtained. Results obtained from fuel elements frequently used in nuclear power plants of the PWR (Pressurized Water Reactors) type, are compared with values resulting from similar analysis. (Author) [es

  4. Finite Element Based Design and Optimization for Piezoelectric Accelerometers

    DEFF Research Database (Denmark)

    Liu, Bin; Kriegbaum, B.; Yao, Q.

    1998-01-01

    A systematic Finite Element design and optimisation procedure is implemented for the development of piezoelectric accelerometers. Most of the specifications of accelerometers can be obtained using the Finite Element simulations. The deviations between the simulated and calibrated sensitivities...

  5. Finite element analysis of plastic recycling machine designed for ...

    African Journals Online (AJOL)

    ... design was evaluated using finite element analysis (FEA) tool in Solid Works Computer ... Also, a minimum factor of safety value of 5.3 was obtained for shredder shaft ... Machine; Design; Recycling; Sustainability; Finite Element; Simulation ...

  6. Obtaining shale oil suitable for lighting

    Energy Technology Data Exchange (ETDEWEB)

    Giraudel, M

    1851-11-12

    Treats with sulphuric acid and then with soda, obtaining 57 per cent of products suitable for lighting in place of the usual 35 to 40 per cent as obtained by present processes. The product has a less disagreeable odor.

  7. Data Element Registry Services

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data Element Registry Services (DERS) is a resource for information about value lists (aka code sets / pick lists), data dictionaries, data elements, and EPA data...

  8. Basic Finite Element Method

    International Nuclear Information System (INIS)

    Lee, Byeong Hae

    1992-02-01

    This book gives descriptions of basic finite element method, which includes basic finite element method and data, black box, writing of data, definition of VECTOR, definition of matrix, matrix and multiplication of matrix, addition of matrix, and unit matrix, conception of hardness matrix like spring power and displacement, governed equation of an elastic body, finite element method, Fortran method and programming such as composition of computer, order of programming and data card and Fortran card, finite element program and application of nonelastic problem.

  9. Radiolabelled cellular blood elements

    International Nuclear Information System (INIS)

    Sinzinger, H.

    1990-01-01

    This book reports on radiolabelled cellular blood elements, covering new advances made during the past several years, in particular the use of Tc-99 as a tracer for blood elements. Coverage extends to several radiolabelled monoclonal antibodies that are specific for blood components and may label blood elements in vivo

  10. Analysis of ADU structure obtained under different precipitation conditions

    International Nuclear Information System (INIS)

    Ramella, Jose L.; Esteban, Adolfo; Mendez De Leo, Lucia P.; Sassone, Ariel; Novara, Oscar E.; Boero, Norma L.; Leyva, Ana G.

    1999-01-01

    ADU is the nominal name for ammonium poly uranate. It is a very complex compound of polymeric structure, which may have, according to precipitation conditions, different chemical composition and crystallographic structure. ADU is used as uranium oxide precursor in the manufacture of fuel elements. In former papers it was proved that if ultrasound is applied during precipitation and digestion the characteristics of the final product (U 3 O 8 UO 2 ) improve. By studying ADU thermal decomposition obtained by ultrasonic application, it was intended to obtain its composition. Therefore, differential thermal gravimetric and differential thermal analyses were performed. Samples were taken from special points and analyzed by X-ray diffraction, infra-red spectroscopy and scanning. An experiment was also designed to identify the products released during heating. Results and conclusions obtained are presented in this work. (author)

  11. INTERACTIVE GLOBAL NETWORK FOR WEATHER DATA OBTAINING, EXCHANGE AND DISSEMINATION

    Directory of Open Access Journals (Sweden)

    Ю.А. Авер’янова

    2012-12-01

    Full Text Available  The possibility to enhance the weather information provision of relevant customers is considered. It is based on the use of the complex global system for weather information obtaining, exchange and dissemination. The structural diagram of the system is proposed. The structural diagram is completed with addition connections that allow to pay strong attention on the most dangerous meteorological phenomena at the critical moment of flight. The proposed approach gives possibility to aircraft crew to select and use specified operative information and increase the probability for proper decision taking. The aircraft are used as the dynamic elements for data obtaining and exchange in the frame of the global system for weather information obtaining, exchange and dissemination.

  12. On the reliability of finite element solutions

    International Nuclear Information System (INIS)

    Prasad, K.S.R.K.

    1975-01-01

    The extent of reliability of the finite element method for analysis of nuclear reactor structures, and that of reactor vessels in particular and the need for the engineer to guard against the pitfalls that may arise out of both physical and mathematical models have been high-lighted. A systematic way of checking the model to obtain reasonably accurate solutions is presented. Quite often sophisticated elements are suggested for specific design and stress concentration problems. The desirability or otherwise of these elements, their scope and utility vis-a-vis the use of large stack of conventional elements are discussed from the view point of stress analysts. The methods of obtaining a check on the reliability of the finite element solutions either through modelling changes or an extrapolation technique are discussed. (author)

  13. Automated rapid chemistry in heavy element research

    International Nuclear Information System (INIS)

    Schaedel, M.

    1994-01-01

    With the increasingly short half-lives of the heavy element isotopes in the transition region from the heaviest actinides to the transactinide elements the demand for automated rapid chemistry techniques is also increasing. Separation times of significantly less than one minute, high chemical yields, high repetition rates, and an adequate detection system are prerequisites for many successful experiments in this field. The development of techniques for separations in the gas phase and in the aqueous phase for applications of chemical or nuclear studies of the heaviest elements are briefly outlined. Typical examples of results obtained with automated techniques are presented for studies up to element 105, especially those obtained with the Automated Rapid Chemistry Apparatus, ARCA. The prospects to investigate the properties of even heavier elements with chemical techniques are discussed

  14. Rare (Earth Elements [score

    Directory of Open Access Journals (Sweden)

    Camilo Méndez

    2014-12-01

    Full Text Available Rare (Earth Elements is a cycle of works for solo piano. The cycle was inspired by James Dillon’s Book of Elements (Vol. I-V. The complete cycle will consist of 14 pieces; one for each selected rare (earth element. The chosen elements are Neodymium, Erbium, Tellurium, Hafnium, Tantalum, Technetium, Indium, Dysprosium, Lanthanium, Cerium, Europium, Terbium, Yttrium and Darmstadtium. These elements were selected due to their special atomic properties that in many cases make them extremely valuable for the development of new technologies, and also because of their scarcity. To date, only 4 works have been completed Yttrium, Technetium, Indium and Tellurium.

  15. Generalized finite elements

    International Nuclear Information System (INIS)

    Wachspress, E.

    2009-01-01

    Triangles and rectangles are the ubiquitous elements in finite element studies. Only these elements admit polynomial basis functions. Rational functions provide a basis for elements having any number of straight and curved sides. Numerical complexities initially associated with rational bases precluded extensive use. Recent analysis has reduced these difficulties and programs have been written to illustrate effectiveness. Although incorporation in major finite element software requires considerable effort, there are advantages in some applications which warrant implementation. An outline of the basic theory and of recent innovations is presented here. (authors)

  16. Thermoluminescence properties of zinc oxide obtained by solution combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R., E-mail: victor.orante@polimeros.uson.mx [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83190 Hermosillo, Sonora (Mexico)

    2014-08-15

    High-dose thermoluminescence dosimetry properties of novel zinc oxide obtained by solution combustion synthesis in a glycine-nitrate process, with a non-stoichiometric value of the elemental stoichiometric coefficient (Φ{sub c}) are presented in this work. Zn O powder samples obtained were annealed afterwards at 900 grades C during 2 h in air. Sintered particles of sizes between ∼ 0.5 and ∼ 2 μm were obtained, according to scanning electron microscopy results. X-ray diffraction indicates the presence of the hexagonal phase of Zn O for the powder samples obtained, before and after thermal annealing, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima; one located at ∼ 149 grades C and another at ∼ 308 grades C, being the latter the dosimetric component of the curve. Dosimetric characterization of non-stoichiometric zinc oxide provided experimental evidence like asymptotic behavior of the Tl signal fading for times greater than 16 h between irradiation and the corresponding Tl readout, as well as the linear behaviour of the dose response without saturation in the dose interval studied (from 12.5 up to 400 Gy). Such characteristics place Zn O phosphors obtained in this work as a promising material for high-dose radiation dosimetry applications (e.g., radiotherapy and food industry). (author)

  17. Thermoluminescence properties of zinc oxide obtained by solution combustion synthesis

    International Nuclear Information System (INIS)

    Orante B, V. R.; Escobar O, F. M.; Cruz V, C.; Bernal, R.

    2014-08-01

    High-dose thermoluminescence dosimetry properties of novel zinc oxide obtained by solution combustion synthesis in a glycine-nitrate process, with a non-stoichiometric value of the elemental stoichiometric coefficient (Φ c ) are presented in this work. Zn O powder samples obtained were annealed afterwards at 900 grades C during 2 h in air. Sintered particles of sizes between ∼ 0.5 and ∼ 2 μm were obtained, according to scanning electron microscopy results. X-ray diffraction indicates the presence of the hexagonal phase of Zn O for the powder samples obtained, before and after thermal annealing, without any remaining nitrate peaks observed. Thermoluminescence glow curves of Zn O obtained after being exposed to beta radiation consists of two maxima; one located at ∼ 149 grades C and another at ∼ 308 grades C, being the latter the dosimetric component of the curve. Dosimetric characterization of non-stoichiometric zinc oxide provided experimental evidence like asymptotic behavior of the Tl signal fading for times greater than 16 h between irradiation and the corresponding Tl readout, as well as the linear behaviour of the dose response without saturation in the dose interval studied (from 12.5 up to 400 Gy). Such characteristics place Zn O phosphors obtained in this work as a promising material for high-dose radiation dosimetry applications (e.g., radiotherapy and food industry). (author)

  18. Elements beyond uranium

    International Nuclear Information System (INIS)

    Seaborg, G.T.; Loveland, W.D.

    1990-01-01

    This book is the 12th volume in a series on transuranium elements. Varied techniques for production of these elements, the methods used in the identification, and the exquisitely refined microchemical techniques required to deal wth samples sometimes involving only a few atoms are described in detail. The chapter on synthesis of the new elements is liberally laced with reminiscences of the proud progenitors as well as the criteria for the discovery of a new chemical element. The authors lament that the superheavy elements (elements in the region of atomic number 114) still elude detection even though their creation should be possible, and some, at least, should survive long enough to be detected. One chapter in the book is devoted to practical applictions of uranium, and the transuranic elements

  19. A CW Gunn diode bistable switching element.

    Science.gov (United States)

    Hurtado, M.; Rosenbaum, F. J.

    1972-01-01

    Experiments with a current-controlled bistable switching element using a CW Gunn diode are reported. Switching rates of the order of 10 MHz have been obtained. Switching is initiated by current pulses of short duration (5-10 ns). Rise times of the order of several nanoseconds could be obtained.

  20. Obtaining of potassium dicyan-argentate

    International Nuclear Information System (INIS)

    Sattarova, M.A.; Solojenkin, P.M.

    1997-01-01

    This work is devoted to obtaining of potassium dicyan-argentate. By means of exchange reaction between silver nitrate and potassium cyanide the potassium dicyan-argentate was synthesized. The analysis of obtained samples was carried out by means of titration and potentiometry.

  1. Treating shale oil to obtain sulfonates

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, H

    1921-01-21

    The process shows as its principal characteristics: (1) treating the oil with chlorsulfonic acid at a temperature of about 100/sup 0/C; (2) the transformation of the sulfonic acid obtained into salts; (3) as new industrial products, the sulfonates obtained and their industrial application as disinfectants for hides and wood.

  2. Strategies for obtaining unpublished drug trial data

    DEFF Research Database (Denmark)

    Wolfe, Nicole; Gøtzsche, Peter C.; Bero, Lisa Anne

    2013-01-01

    Authors of systematic reviews have difficulty obtaining unpublished data for their reviews. This project aimed to provide an in-depth description of the experiences of authors in searching for and gaining access to unpublished data for their systematic reviews, and to give guidance on best...... practices for identifying, obtaining and using unpublished data....

  3. 38 CFR 21.5725 - Obtaining benefits.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Obtaining benefits. 21... benefits. (a) Actions required of the individual. In order to obtain benefits under the educational assistance and subsistence allowance program, an individual must— (1) File a claim for benefits with VA, and...

  4. The solar element

    DEFF Research Database (Denmark)

    Kragh, Helge

    2009-01-01

    of the nineteenth century. In the modest form of a yellow spectral line known as D3, 'helium' was sometimes supposed to exist in the Sun's atmosphere, an idea which is traditionally ascribed to J. Norman Lockyer. Did Lockyer discover helium as a solar element? How was the suggestion received by chemists, physicists...... and astronomers in the period until the spring of 1895, when William Ramsay serendipitously found the gas in uranium minerals? The hypothetical element helium was fairly well known, yet Ramsay's discovery owed little or nothing to Lockyer's solar element. Indeed, for a brief while it was thought that the two...... elements might be different. The complex story of how helium became established as both a solar and terrestrial element involves precise observations as well as airy speculations. It is a story that is unique among the discovery histories of the chemical elements....

  5. The synthetic elements

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, D.C.

    1990-05-01

    Prior to 1940, the heaviest element known was uranium, discovered in 1789. Since that time the elements 93 through 109 have been synthesized and identified and the elements 43, 61, 85, and 87 which were missing form the periodic tables of the 1930's have been discovered. The techniques and problems involved in these discoveries and the placement of the transuranium elements in the periodic table will be discussed. The production and positive identification of elements heavier than Md (Z=101), which have very short half-lives and can only be produced an atom-at-a-time, are very difficult and there have been controversies concerning their discovery. Some of the new methods which have been developed and used in these studies will be described. The prospects for production of still heavier elements will be considered.

  6. The synthetic elements

    International Nuclear Information System (INIS)

    Hoffman, D.C.

    1990-05-01

    Prior to 1940, the heaviest element known was uranium, discovered in 1789. Since that time the elements 93 through 109 have been synthesized and identified and the elements 43, 61, 85, and 87 which were missing form the periodic tables of the 1930's have been discovered. The techniques and problems involved in these discoveries and the placement of the transuranium elements in the periodic table will be discussed. The production and positive identification of elements heavier than Md (Z=101), which have very short half-lives and can only be produced an atom-at-a-time, are very difficult and there have been controversies concerning their discovery. Some of the new methods which have been developed and used in these studies will be described. The prospects for production of still heavier elements will be considered

  7. Fuel element loading system

    International Nuclear Information System (INIS)

    Arya, S.P; s.

    1978-01-01

    A nuclear fuel element loading system is described which conveys a plurality of fuel rods to longitudinal passages in fuel elements. Conveyor means successively position the fuel rods above the longitudinal passages in axial alignment therewith and adapter means guide the fuel rods from the conveyor means into the longitudinal passages. The fuel elements are vibrated to cause the fuel rods to fall into the longitudinal passages through the adapter means

  8. Elements in biological AMS

    International Nuclear Information System (INIS)

    Vogel, J.S.; McAninch, J.; Freeman, S.

    1996-08-01

    AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. 14 C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth's biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed

  9. Analogs for transuranic elements

    International Nuclear Information System (INIS)

    Weimer, W.C.; Laul, J.C.; Kutt, J.C.

    1981-01-01

    A combined theoretical and experimental approach is being used to estimate the long-term environmental and biogeochemical behaviors of selected transuranic elements. The objective of this research is to estimate the effect that long-term (hundreds of years) environmental weathering has on the behavior of the transuranic elements americium and curium. This is achieved by investigating the actual behavior of naturally occurring rare earth elements, especially neodymium, that serve as transuranic analogs. Determination of the analog element behavior provides data that can be used to estimate the ultimate availability to man of transuranic materials released into the environment

  10. Chemistry of superheavy elements

    International Nuclear Information System (INIS)

    Schaedel, M.

    2012-01-01

    The chemistry of superheavy elements - or transactinides from their position in the Periodic Table - is summarized. After giving an overview over historical developments, nuclear aspects about synthesis of neutron-rich isotopes of these elements, produced in hot-fusion reactions, and their nuclear decay properties are briefly mentioned. Specific requirements to cope with the one-atom-at-a-time situation in automated chemical separations and recent developments in aqueous-phase and gas-phase chemistry are presented. Exciting, current developments, first applications, and future prospects of chemical separations behind physical recoil separators ('pre-separator') are discussed in detail. The status of our current knowledge about the chemistry of rutherfordium (Rf, element 104), dubnium (Db, element 105), seaborgium (Sg, element 106), bohrium (Bh, element 107), hassium (Hs, element 108), copernicium (Cn, element 112), and element 114 is discussed from an experimental point of view. Recent results are emphasized and compared with empirical extrapolations and with fully-relativistic theoretical calculations, especially also under the aspect of the architecture of the Periodic Table. (orig.)

  11. Physicochemical characteristics of ozonated sunflower oils obtained by different procedures

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, M. F.; Sanchez, Y.; Gomez, M.; Hernandez, F.; Veloso, M. C.; Pereira, P. A.; Mangrich, A. S.; Andrade, J. B.

    2012-07-01

    Two ozonation procedures for sunflower oils at different applied ozone dosages were carried out. Ozone was obtained from medicinal oxygen and from air. Peroxide, acidity, and iodine indexes, along with density, viscosity and antimicrobial activity were determined. The fatty acid compositions of the samples were analyzed using GC. The content of oxygen was determined using an elemental analysis. Electronic Paramagnetic Resonance was used to measure the organic free radicals. The reactions were achieved up to peroxide index values of 658 and 675 mmolequiv kg1 using medicinal oxygen and air for 5 and 8 hours, respectively. The samples of ozonized sunflower oil did not present organic free radicals, which is a very important issue if these oils are to be used as drugs. The ozonation reaction is more rapid with medicinal oxygen (5 hours) than with air (8 hours). Ozonized sunflower oil with oxygen as an ozone source was obtained with high potential for antimicrobial activity. (Author) 34 refs.

  12. Obtaining the crystal potential by inversion from electron scattering intensities

    International Nuclear Information System (INIS)

    Allen, L.T.; Josefsson, T.W.; Leeb, H.

    1998-01-01

    A method to obtain the crystal potential from the intensities of the diffracted beams in high energy electron diffraction is proposed. It is based on a series of measurements for specific well determined orientations of the incident beam which determine the moduli of all elements of the scattering matrix. Using unitarity and the specific form of the scattering matrix (including symmetries) an overdetermined set of non-linear equations is obtained from these data. Solution of these equations yields the required phase information and allows the determination of a (projected) crystal potential by inversion which is unique up to an arbitrary shift of the origin. The reconstruction of potentials from intensities is illustrated for two realistic examples, a [111] systematic row case in ZnS and a [110] zone axis orientation in GaAs (both noncentrosymmetric crystals)

  13. Obtaining of polycrystalline silicon for semiconductor industry

    International Nuclear Information System (INIS)

    Mukashev, F.; Nauryzbaev, M.; Kolesnikov, B.; Ivanov, Y.

    1996-01-01

    The purpose of the project is to create pilot equipment and optimize the process of obtaining polycrystalline silicon on semi-industrial level. In the past several decades, the historical experience in the developing countries has shown that one of the most promising ways to improve the economy,of a country is to establish semiconductor industry. First of all, the results can help increase defense, national security and create industrial production. The silane method, which has been traditionally' used for obtaining technical and polycrystalline silicon, is to obtain and then to pyrolyzed mono-and poly silanes. Although the traditional methods of obtaining silicon hydrides have specific advantages, such as utilizing by-products, they also have clear shortcomings, i.e. either low output of the ultimate product ( through hydrolysis of Mg 2 Si) or high contents of by-products in it or high contents of dissolving vapors (through decomposing Mg 2 Si in non-water solutions)

  14. Production and characterization of pectinases obtained from ...

    African Journals Online (AJOL)

    Production and characterization of pectinases obtained from Aspergillus fumigatus in submerged fermentation system using pectin extracted from mango peels as carbon source. AL Ezugwu, SOO Eze, FC Chilaka, CU Anyanwu ...

  15. Treatment of biomass to obtain ethanol

    Science.gov (United States)

    Dunson, Jr., James B.; Elander, Richard T [Evergreen, CO; Tucker, III, Melvin P.; Hennessey, Susan Marie [Avondale, PA

    2011-08-16

    Ethanol was produced using biocatalysts that are able to ferment sugars derived from treated biomass. Sugars were obtained by pretreating biomass under conditions of high solids and low ammonia concentration, followed by saccharification.

  16. Silicon dioxide obtained by Polymeric Precursor Method

    International Nuclear Information System (INIS)

    Oliveira, C.T.; Granado, S.R.; Lopes, S.A.; Cavalheiro, A.A.

    2011-01-01

    The Polymeric Precursor Method is able for obtaining several oxide material types with high surface area even obtained in particle form. Several MO 2 oxide types such as titanium, silicon and zirconium ones can be obtained by this methodology. In this work, the synthesis of silicon oxide was monitored by thermal analysis, XRD and surface area analysis in order to demonstrate the influence of the several synthesis and calcining parameters. Surface area values as higher as 370m2/g and increasing in the micropore volume nm were obtained when the material was synthesized by using ethylene glycol as polymerizing agent. XRD analysis showed that the material is amorphous when calcinated at 600°C in despite of the time of calcining, but the material morphology is strongly influenced by the polymeric resin composition. Using Glycerol as polymerizing agent, the pore size increase and the surface area goes down with the increasing in decomposition time, when compared to ethylene glycol. (author)

  17. Process for obtaining cobalt and lanthanum nickelate

    International Nuclear Information System (INIS)

    Tapcov, V.; Samusi, N.; Gulea, A.; Horosun, I.; Stasiuc, V.; Petrenco, P.

    1999-01-01

    The invention relates to the process for obtaining polycrystalline ceramics of cobalt and lanthanum nickelate with the perovskite structure from coordinative hetero metallic compounds. The obtained products can be utilized in the industry in the capacity of catalysts. Summary of the invention consists in obtaining polycrystalline ceramics LaCoO 3 and LaNiO 3 with the perovskite structure by pyrolysis of the parent compounds, namely, the coordinative hetero metallic compounds of the lanthanum cobalt or lanthanum nickel. The pyrolysis of the parent compound runs during one hour at 800 C. The technical result of the invention consists in lowering the temperature of the parent compound pyrolysis containing the precise ratio of metals necessary for ceramics obtaining

  18. Elemental microanalysis of botanical specimens using the Melbourne Proton Microprobe

    International Nuclear Information System (INIS)

    Mazzolini, A.P.J.; Legge, G.J.F.

    1978-01-01

    A proton microprobe has been used to obtain the distribution of elements of various botanical specimens. This paper presents preliminary results obtained by the irradiation of certain organs of the wheat plant

  19. Berkeley new element program

    International Nuclear Information System (INIS)

    Ghiorso, A.

    1975-09-01

    The work done with element 106 is reviewed, and a new experiment which bears on the properties of the isotope of mass 260 with atomic number 104 is discussed. It is noted that in the case of element 106 a link is demonstrated to the granddaughter as well as the daughter

  20. Elemental Food for Thought

    Science.gov (United States)

    Cady, Susan

    2005-01-01

    One of the first tasks students learn in chemistry is to pronounce and spell the names of elements and learn their corresponding chemical symbols. Repetitive oral recitation is commonly used to learn this information, but games and puzzles can make this task creative, variable, and fun. Elemental Food for Thought is a puzzlelike activity that…

  1. Nuclear fuel element

    International Nuclear Information System (INIS)

    Mogard, J.H.

    1977-01-01

    A nuclear fuel element is disclosed for use in power producing nuclear reactors, comprising a plurality of axially aligned ceramic cylindrical fuel bodies of the sintered type, and a cladding tube of metal or metal alloys, wherein said cladding tube on its cylindrical inner surface is provided with a plurality of slightly protruding spacing elements distributed over said inner surface

  2. Proceedings of transuranium elements

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The identification of the first synthetic elements was established by chemical evidence. Conclusive proof of the synthesis of the first artificial element, technetium, was published in 1937 by Perrier and Segre. An essential aspect of their achievement was the prediction of the chemical properties of element 43, which had been missing from the periodic table and which was expected to have properties similar to those of manganese and rhenium. The discovery of other artificial elements, astatine and francium, was facilitated in 1939-1940 by the prediction of their chemical properties. A little more than 50 years ago, in the spring of 1940, Edwin McMillan and Philip Abelson synthesized element 93, neptunium, and confirmed its uniqueness by chemical means. On August 30, 1940, Glenn Seaborg, Arthur Wahl, and the late Joseph Kennedy began their neutron irradiations of uranium nitrate hexahydrate. A few months later they synthesized element 94, later named plutonium, by observing the alpha particles emitted from uranium oxide targets that had been bombarded with deuterons. Shortly thereafter they proved that is was the second transuranium element by establishing its unique oxidation-reduction behavior. The symposium honored the scientists and engineers whose vision and dedication led to the discovery of the transuranium elements and to the understanding of the influence of 5f electrons on their electronic structure and bonding. This volume represents a record of papers presented at the symposium

  3. Chinese dietary composition and element ingestion

    International Nuclear Information System (INIS)

    Zhu Hongda

    1990-01-01

    Based on the dietary composition and results of some nutrients obtained from the second Nationwide Nutrition Survey in 1982, as well as recently published element contents in various Chinese food, the resultant dietary intake of 19 kinds of elements and 17 radionuclides for Chinese public (mainly for male adults) were estimated. This estimation might be used as basis for development of Chinese Reference Man and estimation of the public background exposure

  4. Matrix Elements in Fermion Dynamical Symmetry Model

    Institute of Scientific and Technical Information of China (English)

    LIU Guang-Zhou; LIU Wei

    2002-01-01

    In a neutron-proton system, the matrix elements of the generators for SO(8) × SO(8) symmetry areconstructed explicitly, and with these matrix elements the low-lying excitation spectra obtained by diagonalization arepresented. The excitation spectra for SO(7) nuclei Pd and Ru isotopes and SO(6) r-soft rotational nuclei Xe, Ba, andCe isotopes are calculated, and comparison with the experimental results is carried out.

  5. Matrix Elements in Fermion Dynamical Symmetry Model

    Institute of Scientific and Technical Information of China (English)

    LIUGuang-Zhou; LIUWei

    2002-01-01

    In a neutron-proton system,the matrix elements of the generators for SO(8)×SO(8) symmetry are constructed exp;icitly,and with these matrix elements the low-lying excitation spsectra obtained by diagonalization are presented.The excitation spectra for SO(7) nuclei Pd and Ru isotopes and SO(6) r-soft rotational nuclei Xe,Ba,and Ce isotopes are calculated,and comparison with the experimental results is carried out.

  6. Chelate forms of biometalls. Theoretical aspects of obtaining and characteristics

    Directory of Open Access Journals (Sweden)

    A. Kapustyan

    2017-04-01

    Full Text Available The problem of microelements bioavailability is highlighted and the correct ways of its solution are substantiated as a result of generalization of theoretical aspects of obtaining of the biometals chelate forms. The characteristics of the main biogenic elements, their physiological significance, electrochemical properties are presented. The main examples of the participation of biometals in various biological processes are given. The properties and the structure peculiarities of biometals coordination complexes are considered in detail. It is shown that in obtaining of biometals chelate forms, there is the mutual selectivity and the affinity of biometals and ligands. The main factors of obtaining a hard metal complex are given. Potential bioligands for obtaining bioavailable forms of microelements are detailed. Among them there are amino acids, peptides, proteins, nucleic acids, carbohydrates. The possible character of complexation depending on the nature of the bioligand is indicated. Practical examples of preparation of biometals mixed ligand complexes are given. The expediency of using metabolic products and processing of lactic acid bacteria as promising components of mixed ligand chelate complexes is substantiated. These substances contain in their composition a mass of potential donor atoms that are capable to form covalent and coordination bonds with biomethalles, and also possess high biological and immunotropic activities. The use of this system in the biocoordination compounds of the "metals of life" can provide a synergistic effect of the components, significantly to expand the range of their physiological activity and to increase the degree of assimilation by the body.

  7. Obtaining of ceramics biphasic dense and porous

    International Nuclear Information System (INIS)

    Pallone, E.M.J.A.; Rigo, E.C.S.; Fraga, A.F.

    2010-01-01

    Among the bioceramic hydroxyapatite (HAP) and beta-tricalcium phosphate (beta-TCP) are materials commonly used in biomedical field. Their combined properties result in a material with absorbable and at the same time with bioactive surface. Called biphasic ceramics such materials respond more quickly when exposed to physiological environment. In this work, powders of HAP/beta-TCP were obtained by chemical precipitation. After obtaining the post-phase was added at a ratio of 0, 15% and 30w% aqueous solutions of corn starch in order to obtain porous bodies. After mixing the resulting solutions were dried, resigned in tablet form and sintered at 1300 deg C. The initial powder was characterized by X-ray diffraction with Rietveld refinement to quantify the phases present. Bodies-of-evidence has been characterized by calculating the bulk density, X-ray diffraction (XRD), scanning electron microscopy and diametral compression. (author)

  8. Organoclays obtaining starting up of clays sodium

    International Nuclear Information System (INIS)

    Silva, M.M. da; Mota, M.F.; Oliveira, G.C. de; Rodrigues, M.G.F.

    2012-01-01

    Clays have several applications in many areas of fields of technology, however, modification of these materials using organic compounds can be performed to obtain further hydrophobic materials, for applications in the adsorption of organic pollutants. This study aimed to analyze the effects of modifying two clays using sodium quaternary ammonium surfactants through ion exchange reaction process, in obtaining organoclays. The samples with sodium and organoclays were characterized by the techniques of X-ray diffraction (XRD), Infrared Spectroscopy in the region (IV), Gravimetric and Differential Thermal Analysis (DTA / TG) and organic adsorption tests. The results show that the process of obtaining organoclay is efficient, and materials have the potential for future applications in removing organic contaminants. (author)

  9. Obtain of uranium concentrates from fertil liquids

    International Nuclear Information System (INIS)

    Narvaez Castillo, W.A.

    1992-01-01

    This research tried to encounter the form to remove uranium from the rock in the best way, for that it was used different process like leaching, extraction, concentration and precipitation. To leach the mineral was chosen basic leaching, using a mixture of carbonate-sodium bicarbonate, this method is more adequated for the basic nature of the mineral. In extraction was used specific uranium ionic interchanges, so was chosen a tertiary amine like Alamina 336. The concentration phase is intimately binding with the extraction by ionic interchange, for the capability of resine's extraction to obtain concentrated liquids. When the liquids were obtained with high concentration of uranium in the same time were purified and then were precipitated, for that we employed a precipitant agent like: Sodium hydroxide, Amonium hydroxide, Magnesium hydroxide, Hydrogen peroxide and phosphates. With all concentrates we obtain the YELLOW CAKE

  10. Experiments for obtaining field influence mass particles.

    CERN Document Server

    Yahalomi, E

    2010-01-01

    Analyzing time dilation experiments the existence of a universal field interacting with moving mass particles is obtained. It is found that mass particle changes its properties depend on its velocity relative to this universal scalar field and not on its velocity relative to the laboratory. High energy proton momentum, energy and mass were calculated obtaining new results. Experiments in high energy accelerators are suggested as additional proofs for the existence of this universal field. This universal field may explain some results of other high energy experiments.

  11. Trace element content of precipitation in a remote area

    International Nuclear Information System (INIS)

    Merritt, W.F.

    1976-01-01

    Rain and snow, sampled over a period of 18 months at Chalk River Nuclear Laboratories, were analysed for 40 elements by thermal neutron activation analysis. Correlation analysis revealed that the elements detected could be divided into groups of similar behaviour. Storm tracks for the events sampled were obtained, but only generalizations as to the probable origin of the trace elements could be made. Deuterium content of the samples was not correlated with levels of trace elements. (author)

  12. A simple methodology for obtaining X-ray color images in scanning electron microscopy

    International Nuclear Information System (INIS)

    Veiga, M.M. da; Pietroluongo, L.R.V.

    1985-01-01

    A simple methodology for obtaining at least 3 elements X-ray images in only one photography is described. The fluorescent X-ray image is obtained from scanning electron microscopy with energy dispersion analysis system. The change of detector analytic channels, color cellophane foils and color films are used sequentially. (M.C.K.) [pt

  13. 42 CFR 420.304 - Procedures for obtaining access to books, documents, and records.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Procedures for obtaining access to books, documents... Books, Documents, and Records of Subcontractors § 420.304 Procedures for obtaining access to books... following elements: (1) Reasonable identification of the books, documents, and records to which access is...

  14. Obtaining the Andersen's chart, triangulation algorithm

    DEFF Research Database (Denmark)

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    Andersen’s chart (Andersen & Berre, 1999) is a graphical method of observing cyclic soil response. It allows observing soil response to various stress amplitudes that can lead to liquefaction, excess plastic deformation or stabilizing soil response. The process of obtaining the original chart has...

  15. Purification of alcohol obtained from molasses

    Energy Technology Data Exchange (ETDEWEB)

    Visnevskaya, G L; Egorov, A S; Sokol' skaya, E V

    1960-01-01

    A study of the composition of alcohol liquids on different plates of a fractionation column of indirect action during purification of alcohol obtained from normal and defective molasses, and from starch raw material, showed that there were two local strength minima in the lower part of the column and on the plates (adjacent and feed). Aldehydes behaved as a typical head impurity; a noticeable increase in their concentration occurred only on the highest plates in the fractionation column. In the zone of the column containing liquids of a strength of 86 to 94% alcohol by weight a sharply pronounced local maximum of ester accumulation were observed, provisionally designated as intermediate, whose presence is apparently one of the causes of the specific sharp taste of alcohol obtained from molasses. These esters hinder the obtaining of high-grade alcohols which are standard in respect to ester content and oxidizability test. Reduction with 0.05N KMnO/sub 4/ occurs most rapidly with alcohol liquids in the zone of ester accumulation; purification of alcohols obtained from grain and potato raw material resulted in no zones of ester accumulation in the column.

  16. Obtaining shale distillate free from sulphur

    Energy Technology Data Exchange (ETDEWEB)

    Heyl, G E

    1917-09-14

    A process whereby, from sulfur-containing shale, products free from sulfur may be obtained, consisting of mixing with the finely ground shale a portion of iron salts containing sufficient metal to unite with all the sulfur in the shale and form sulfide therewith, grinding the mixture to a fine state of subdivision and subsequently subjecting it to destructive distillation.

  17. Obtaining a minimal set of rewrite rules

    CSIR Research Space (South Africa)

    Davel, M

    2005-11-01

    Full Text Available In this paper the authors describe a new approach to rewrite rule extraction and analysis, using Minimal Representation Graphs. This approach provides a mechanism for obtaining the smallest possible rule set – within a context-dependent rewrite rule...

  18. Obtainment of tantalum oxide from national ores

    International Nuclear Information System (INIS)

    Pinatti, D.G.; Ribeiro, S.; Martins, A.H.

    1988-01-01

    The experimental results of tantalum oxides (Ta 2 O 5 ) obtainment from Brazilian ores of tantalite and columbite are described. This study is a part of the technologic and scientific research design of refractory metals (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W) and correlate ceramics. (C.G.C.) [pt

  19. Isolation and characterization of microcrystalline cellulose obtained ...

    African Journals Online (AJOL)

    In this study, microcrystalline cellulose, coded MCC-PNF, was obtained from palm nut (Elaeis guineensis) fibres. MCC-PNF was examined for its physicochemical and powder properties. The powder properties of MCC-PNF were compared to those of the best commercial microcrystalline cellulose grade, Avicel PH 101.

  20. 47 CFR 54.615 - Obtaining services.

    Science.gov (United States)

    2010-10-01

    ... provided under § 54.621, that the requester cannot obtain toll-free access to an Internet service provider... thing of value; (6) If the service or services are being purchased as part of an aggregated purchase... submitted and select the most cost-effective alternative. (b) Receiving supported rate. Except with regard...

  1. Development of the NAA Laboratory for an Accreditation Obtains

    International Nuclear Information System (INIS)

    Sri Wardani; Rina M, Th.; Sunarko, M.; Ratnawati, E.

    2004-01-01

    The evaluation of capability of the neutron activation analysis comparative method and laboratory equipment at P2TRR have been performed by analyzed a reference standard materials prepared by NIST, namely: SRM 1646a and SRM 1648 by a both of comparative and ko- NAA methods. From the analysis results used a comparative method shown that the method and laboratory equipment used at P2TRR obtained in a good precision, accuracy and high sensitivity. In this experiments a few elements could analyzed, namely: V, Ti, Mn, Cl, As, Sm, La, Na, Sc, Cr, Fe, Co, Se, Br, In, Sb, Ba, Cs, Ce, W, U, and Zn. The deviation values results compared with certificate values (NIST) obtained in a range 2 - 12.5% with confidence levels in range 68 - 98%. While, a reference standard material of SRM 1648 analyzed by k 0 -NAA method shown that the method need more research and study continued. From the qualitatively analysis results for short-lived nuclides category analysis by k 0 -NAA could identified a few elements, namely: V, Cu, Na, As and U with standard deviation values in range 1- 11% and limit detection values are 1.6 (U), 6.4 (Cu), 11.2 (V), 73.3 (As) and 199.9 (Na) μg/g for a SRM 1648. For analysis of CRM 8 the results obtained on standard deviation values in range 1 - 13 % and limit detection of 0.71 (Cu), 1.2 (As), 2.4 (V) and 375.9 (Na) μg/g. (author)

  2. Discovery of element 112

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, S. [GSI, Darmstadt (Germany)

    1996-12-31

    The new elements 110, 111, and 112 were synthesized and unambiguously identified in experiments at SHIP. Due to strong shell effects the dominant decay mode is not fission, but emission of alpha particles. Theoretical investigations predict that maximum shell effects should exist in nuclei near proton number 114 and neutron number 184. Measurements give hope that isotopes of element 114 close to the island of spherical Superheavy Elements could be produced by fusion reactions using {sup 118}Pb as target. systematic studies of the reaction cross-sections indicate that transfer of nucleons is the important process to initiate the fusion.

  3. Nuclear fuel element

    International Nuclear Information System (INIS)

    Grossman, L.N.; Levin, H.A.

    1975-01-01

    A nuclear fuel element has disposed therein an alloy having the essential components of nickel, titanium and zirconium, and the alloy reacts with water, water vapor and reactive gases at reactor ambient temperatures. The alloy is disposed in the plenum of the fuel element in the form of particles in a hollow gas permeable container having a multiplicity of openings of size smallr than the size of the particles. The container is preferably held in the spring in the plenum of the fuel element. (E.C.B.)

  4. Elemental diffusion in stars

    International Nuclear Information System (INIS)

    Michaud, Georges; Montmerle, Thierry

    1977-01-01

    This paper is dealing with the origin of the elements in the universe. The scheme of nucleosynthesis is kept to explain the stellar generation of helium, carbon, etc... from the initial hydrogen; but a nonlinear theory is then elaborated to account for the anomalous abundances which were observed. The chemical elements would diffuse throughout the outer layers of a star under the action of the opposite forces of gravitation and radiation. This theory, with completing the nucleosynthesis, would contribute to give a consistent scheme of the elemental origin and abundances [fr

  5. Overlapping Schwarz for Nonlinear Problems. An Element Agglomeration Nonlinear Additive Schwarz Preconditioned Newton Method for Unstructured Finite Element Problems

    Energy Technology Data Exchange (ETDEWEB)

    Cai, X C; Marcinkowski, L; Vassilevski, P S

    2005-02-10

    This paper extends previous results on nonlinear Schwarz preconditioning ([4]) to unstructured finite element elliptic problems exploiting now nonlocal (but small) subspaces. The non-local finite element subspaces are associated with subdomains obtained from a non-overlapping element partitioning of the original set of elements and are coarse outside the prescribed element subdomain. The coarsening is based on a modification of the agglomeration based AMGe method proposed in [8]. Then, the algebraic construction from [9] of the corresponding non-linear finite element subproblems is applied to generate the subspace based nonlinear preconditioner. The overall nonlinearly preconditioned problem is solved by an inexact Newton method. Numerical illustration is also provided.

  6. On the Necessity of Using Element No.155 in the Chemical Physical Calculations: Again on the Upper Limit in the Periodic Table of Elements

    Directory of Open Access Journals (Sweden)

    Khazan A.

    2010-10-01

    Full Text Available It is shown how the properties of different elements of the Periodic System of Elements can be obtained using the properties of the theoretically predicted heaviest element No.155 (it draws the upper principal limit of the Table, behind which stable elements cannot exist. It is suggested how the properties of element No.155 can be used in the synthesis of superheavy elements. An analysis of nuclear reactions is also produced on the same basis.

  7. Trace Elements in Cardiovascular Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Masironi, R. [Cardiovascular Diseases Unit, World Health Organization, Geneva (Switzerland)

    1970-07-01

    Cardiovascular diseases are the leading cause of death in industrialized countries. Their incidence increases, apparently, as a, function of technological progress so that in the future they may become a major public health problem in developing countries too. Early diagnosis and prevention are the tools best suited to curb such an alarming trend, but our knowledge of these topics is unsatisfactory, Valuable information would be obtained through a systematic investigation of trace elements in relation to cardiovascular function and to various types of cardiovascular diseases. Such studies would provide clues to the following questions: 1. Why does the incidence and type of cardiovascular disease differ from one country to another? May this be related to differences in tissue mineral concentrations among various population groups? 2. Which trace elements if any are beneficial to cardiovascular health, and which are harmful ones that may act as aetiological agents for some cardiovascular diseases? 3. Is it possible to utilize measurements of mineral element concentration for diagnostic purposes in cardiovascular disease? (author)

  8. Fast breeder fuel element development

    International Nuclear Information System (INIS)

    Marth, W.; Muehling, G.

    1983-08-01

    This report is a compilation of the papers which have been presented during a seminar ''Fast Breeder Fuel Element Development'' held on November 15/16, 1982 at KfK. The papers give a survey of the status, of the obtained results and of the necessary work, which still has to be done in the frame of various development programmes for fast breeder fuel elements. In detail the following items were covered by the presentations: - the requirements and boundary conditions for the design of fuel pins and elements both for the reference concept of the SNR 300 core and for the large, commercial breeder type of the future (presentation 1,2 and 6); - the fabrication, properties and characterization of various mixed oxide fuel types (presentations 3,4 and 5); - the operational fuel pin behaviour, limits of different design concepts and possible mechanism for fuel pin failures (presentations (7 and 8); - the situation of cladding- and wrapper materials development especially with respect to the high burn-up values of commercial reactors (presentations 9 and 10); - the results of the irradiation experiments performed under steady-state and non-stationary operational conditions and with failed fuel pins (presentations 11, 12, 13 and 14). (orig./RW) [de

  9. Elemental composition of cosmic ray

    International Nuclear Information System (INIS)

    Yanagida, Shohei

    1987-01-01

    The report first summarizes some data that have been obtained so far from observation of isotopes and elements in cosmic rays in the low energy region. Then, objectives of studies planned to be carried out with Astromag are outlined and the number of incident particles expected to be measured by baloon observation is estimated. Heavy elements with atomic numbers of greater than 30 are considered to be formed through neutron absorption reactions by the s- or r-process. Observations show that products of the r-process is abundant in cosmic ray sources. The escape length depends on energy. In relation to this, it has been reported that the ratios Ar-Fe and Ca-Fe increase above 200 GeV-n while such a tendency is not observed for K, Sc, Ti or V. Thus, no satisfactory models are available at present which can fully explain the changes in the escape length. The ratio 3 He- 4 He in the range of 5 - 10 GeV-n is inconsistent with the general theory that interprets the escape length of heavy elements. Some models, including the supermetallicity model and Wolf Rayet theory, have been proposed to explain unusual ratios of isotopes in cosmic rays, but more measurements are required to verify them. It is expected that Astromag can serve to make observations that can clarify these points. (Nogami, K.)

  10. Zinc resistance within swine associated methicillin resistant Staphylococcus aureus (MRSA) isolates in the USA is associated with MLST lineage

    Science.gov (United States)

    Zinc resistance in livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA) is mediated by the czrC gene co-located with the mecA gene, encoding methicillin resistance, on the type V SCCmec element. Since the czrC gene and the mecA gene are co-located on the SCCmec element, it has ...

  11. Transuranium element recovering method for spent nuclear fuel

    International Nuclear Information System (INIS)

    Todokoro, Akio; Kihara, Yoshiyuki; Okada, Hisashi

    1998-01-01

    Spent fuels are dissolved in nitric acid, the obtained dissolution liquid is oxidized by electrolysis, and nitric acid of transuranium elements are precipitated together with nitric acid of uranium elements from the dissolution solution and recovered. Namely, the transuranium elements are oxidized to an atomic value level at which nitric acid can be precipitated by an oxidizing catalyst, and cooled to precipitate nitric acid of transuranium elements together with nitric acid of transuranium elements, accordingly, it is not necessary to use a solvent which has been used so far upon recovering transuranium elements. Since no solvent waste is generated, a recovery method taking the circumstance into consideration can be provided. Further, nitric acid of uranium elements and nitric acid of transuranium elements precipitated and recovered together are dissolved in nitric acid again, cooled and only uranium elements are precipitated selectively, and recovered by filtration. The amount of wastes can be reduced to thereby enabling to mitigate control for processing. (N.H.)

  12. Bridge element deterioration rates.

    Science.gov (United States)

    2008-10-01

    This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

  13. 2. Transuranic elements

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Methods of sample collection, sample storage, sample procedures and radioanalytical procedures for transuranic elements in marine environment are reviewed and recommended. Alpha spectrometry and scintillation techniques are used for measurement of isotopic content. Separation processes for samples are described

  14. Heavy element research

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Heavy element research activities in metallurgy and ceramics during 1976 at Lawrence Berkeley Laboratory are reviewed. Topics include: microstructure, properties and alloy design; ceramic alloy program; high resolution and high voltage electron microscopy; and powder metallurgy

  15. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Hindle, E.D.

    1981-01-01

    An array of rods comprising zirconium alloy sheathed nuclear fuel pellets assembled to form a fuel element for a pressurised water reactor is claimed. The helium gas pressure within each rod differs substantially from that of its closest neighbours

  16. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Hindle, E.D.

    1984-01-01

    The fuel elements for a pressurised water reactor comprise arrays of rods of zirconium alloy sheathed nuclear fuel pellets. The helium gas pressure within each rod differs substantially from that of its closest neighbours

  17. Transposable elements in cancer.

    Science.gov (United States)

    Burns, Kathleen H

    2017-07-01

    Transposable elements give rise to interspersed repeats, sequences that comprise most of our genomes. These mobile DNAs have been historically underappreciated - both because they have been presumed to be unimportant, and because their high copy number and variability pose unique technical challenges. Neither impediment now seems steadfast. Interest in the human mobilome has never been greater, and methods enabling its study are maturing at a fast pace. This Review describes the activity of transposable elements in human cancers, particularly long interspersed element-1 (LINE-1). LINE-1 sequences are self-propagating, protein-coding retrotransposons, and their activity results in somatically acquired insertions in cancer genomes. Altered expression of transposable elements and animation of genomic LINE-1 sequences appear to be hallmarks of cancer, and can be responsible for driving mutations in tumorigenesis.

  18. Divergent picornavirus IRES elements

    DEFF Research Database (Denmark)

    Belsham, Graham

    2009-01-01

    Internal ribosome entry site (IRES) elements were first identified about 20 years ago within the 5' untranslated region of picornavirus RNAs. They direct a cap-independent mechanism of translation initiation on the viral RNA. Within the picornavirus family it is now known that there are four...... classes of IRES element which vary in size (450-270nt), they also have different, complex, secondary structures and distinct requirements for cellular proteins to allow them to function. This review describes the features of each class of picornavirus IRES element but focuses on the characteristics...... of the most recently described group, initially identified within the porcine teschovirus-1 RNA, which has strong similarities to the IRES elements from within the genomes of hepatitis C virus and the pestiviruses which are members of the flavivirus family. The selection of the initiation codon...

  19. Processing of hydroxyapatite obtained by combustion synthesis

    International Nuclear Information System (INIS)

    Canillas, M.; Rivero, R.; García-Carrodeguas, R.; Barba, F.; Rodríguez, M.A.

    2017-01-01

    One of the reasons of implants failure are the stress forces appearing in the material–tissue interface due to the differences between their mechanical properties. For this reason, similar mechanical properties to the surrounding tissue are desirable. The synthesis of hydroxyapatite by solution combustion method and its processing have been studied in order to obtain fully dense ceramic bodies with improved mechanical strength. Combustion synthesis provides nanostructured powders characterized by a high surface area to facilitate the following sintering. Moreover, synthesis was conducted in aqueous and oxidizing media. Oxidizing media improve homogenization and increase the energy released during combustion. It gives rise to particles whose morphology and size suggest lower surface energies compared with aqueous media. The obtained powders were sintered by using a controlled sintering rate schedule. Lower surfaces energies minimize the shrinkage during sintering and relative densities measurements and diametral compression test confirm improved densification and consequently mechanical properties. [es

  20. Process for obtaining luminescent glass layers

    International Nuclear Information System (INIS)

    Heindi, R.; Robert, A.

    1984-01-01

    Process for obtaining luminescent glass layers, application to the production of devices provided with said layers and to the construction of photoscintillators. The process comprises projecting onto a support, by cathodic sputtering, the material of at least one target, each target including silica and at least one chemical compound able to give luminescent centers, such as a cerium oxide, so as to form at least one luminescent glass layer of the said support. The layer or layers formed preferably undergo a heat treatment such as annealing in order to increase the luminous efficiency thereof. It is in this way possible to form a scintillating glass layer on the previously frosted entrance window of a photomultiplier in order to obtain an integrated photoscintillator

  1. Processing of hydroxyapatite obtained by combustion synthesis

    Directory of Open Access Journals (Sweden)

    M. Canillas

    2017-09-01

    Full Text Available One of the reasons of implants failure are the stress forces appearing in the material–tissue interface due to the differences between their mechanical properties. For this reason, similar mechanical properties to the surrounding tissue are desirable. The synthesis of hydroxyapatite by solution combustion method and its processing have been studied in order to obtain fully dense ceramic bodies with improved mechanical strength. Combustion synthesis provides nanostructured powders characterized by a high surface area to facilitate the following sintering. Moreover, synthesis was conducted in aqueous and oxidizing media. Oxidizing media improve homogenization and increase the energy released during combustion. It gives rise to particles whose morphology and size suggest lower surface energies compared with aqueous media. The obtained powders were sintered by using a controlled sintering rate schedule. Lower surfaces energies minimize the shrinkage during sintering and relative densities measurements and diametral compression test confirm improved densification and consequently mechanical properties.

  2. Novel porcine repetitive elements

    Directory of Open Access Journals (Sweden)

    Nonneman Dan J

    2006-12-01

    Full Text Available Abstract Background Repetitive elements comprise ~45% of mammalian genomes and are increasingly known to impact genomic function by contributing to the genomic architecture, by direct regulation of gene expression and by affecting genomic size, diversity and evolution. The ubiquity and increasingly understood importance of repetitive elements contribute to the need to identify and annotate them. We set out to identify previously uncharacterized repetitive DNA in the porcine genome. Once found, we characterized the prevalence of these repeats in other mammals. Results We discovered 27 repetitive elements in 220 BACs covering 1% of the porcine genome (Comparative Vertebrate Sequencing Initiative; CVSI. These repeats varied in length from 55 to 1059 nucleotides. To estimate copy numbers, we went to an independent source of data, the BAC-end sequences (Wellcome Trust Sanger Institute, covering approximately 15% of the porcine genome. Copy numbers in BAC-ends were less than one hundred for 6 repeat elements, between 100 and 1000 for 16 and between 1,000 and 10,000 for 5. Several of the repeat elements were found in the bovine genome and we have identified two with orthologous sites, indicating that these elements were present in their common ancestor. None of the repeat elements were found in primate, rodent or dog genomes. We were unable to identify any of the replication machinery common to active transposable elements in these newly identified repeats. Conclusion The presence of both orthologous and non-orthologous sites indicates that some sites existed prior to speciation and some were generated later. The identification of low to moderate copy number repetitive DNA that is specific to artiodactyls will be critical in the assembly of livestock genomes and studies of comparative genomics.

  3. Fuel element store

    International Nuclear Information System (INIS)

    Wieser, R.

    1987-01-01

    The spherical fuel elements are stored dry in cans. The cans themselves are stacked in parallel storage shafts, which are combined into a rectangular storage space. The storage space is made earthquake-proof by surrounding it with concrete. It consists of a ceiling assembled from several steel parts, which is connected to the floor by support elements. A cooling air ventilation station supplies the individual storage shaft and therefore the cans with cooling air via incoming and outgoing pipes. (DG) [de

  4. Intrusion detection system elements

    International Nuclear Information System (INIS)

    Eaton, M.J.; Mangan, D.L.

    1980-09-01

    This report highlights elements required for an intrusion detection system and discusses problems which can be encountered in attempting to make the elements effective. Topics discussed include: sensors, both for exterior detection and interior detection; alarm assessment systems, with the discussion focused on video assessment; and alarm reporting systems, including alarm communication systems and dislay/console considerations. Guidance on careful planning and design of a new or to-be-improved system is presented

  5. Structural elements design manual

    CERN Document Server

    Draycott, Trevor

    2012-01-01

    Gives clear explanations of the logical design sequence for structural elements. The Structural Engineer says: `The book explains, in simple terms, and with many examples, Code of Practice methods for sizing structural sections in timber, concrete,masonry and steel. It is the combination into one book of section sizing methods in each of these materials that makes this text so useful....Students will find this an essential support text to the Codes of Practice in their study of element sizing'.

  6. Atoms, molecules & elements

    CERN Document Server

    Graybill, George

    2007-01-01

    Young scientists will be thrilled to explore the invisible world of atoms, molecules and elements. Our resource provides ready-to-use information and activities for remedial students using simplified language and vocabulary. Students will label each part of the atom, learn what compounds are, and explore the patterns in the periodic table of elements to find calcium (Ca), chlorine (Cl), and helium (He) through hands-on activities.

  7. Macro-Elements and Trace Elements in Cereal Grains Cultivated in Latvia

    Directory of Open Access Journals (Sweden)

    Jākobsone Ida

    2015-09-01

    Full Text Available Cereal-based foods have great importance in the compensation of micro- and trace element deficiency, because 50% of the foods produced worldwide are made up of cereal grains. The aim of the research was to determine the concentration of macro-elements and trace elements in different cereals cultivated in Latvia. Various cereals were used in the research: rye (n = 45, barley (n = 54, spring wheat (n = 27, winter wheat (n = 53, triticale (n = 45 and oats (n = 42. Thirteen macro- and trace elements (Cd, Pb, Ni, Cr, Al, Cu, K, Na, Mn, Fe, Zn, Mg, Ca were determined in cereal grain samples (n = 266. Macro-elements and trace elements varied significantly (p < 0.01 or p < 0.001. The highest concentrations of macro- and trace elements were found in oats and the lowest in rye. The obtained data will expand the opportunity for food and nutrition scientists to evaluate content of the examined elements in grain products, and dietary consumption (bioavailability of the examined macro-elements and trace elements.

  8. Process for obtaining ammonium uranyl tri carbonate

    International Nuclear Information System (INIS)

    Santos, L.R. dos; Riella, H.G.

    1992-01-01

    The procedure adopted for obtaining Ammonium Uranyl Carbonate (AUC) from uranium hexafluoride (U F 6 ) in a aqueous solutions of ammonium hydrogen carbonate is described in this work. The precipitation is made in temperature and pH controlled. This process consists of three steps: evaporation of U F 6 , AUC precipitation and filtration of the AUC slurry. An attempt is made of correlate the parameters involved in the precipitation process of AUC with its and U O 2 characteristics. (author)

  9. Superconducting materials fabrication process and materials obtained

    International Nuclear Information System (INIS)

    Lafon, M.O.; Magnier, C.

    1989-01-01

    The preparation process of a fine powder of YBaCuO type superconductors of easy sintering comprises: mixing in presence of alcohol an aqueous solution of rare earth nitrate or acetate, alkaline earth nitrate or acetate and copper nitrate or acetate and an oxalic acid solution, the pH value of the mixture is comprised between 2 and 4, the obtained precipitate is separated, dried, calcined and eventually crushed [fr

  10. PULP OBTAINING METHOD FOR PACKAGE PRODUCTION

    Directory of Open Access Journals (Sweden)

    V. V. Kuzmich

    2015-01-01

    Full Text Available The paper presents a new method for obtaining pulp which is used for production of cardboard, paper and package while using carbon dioxide and hydrazine hydrate and neutral-sulfite  shive cooking. Output increase of  the desired product can be explained by reduction in destruction of plant raw material carbohydrates during its cooking process. Quality improvement of the desired product (improvement in bleaching and output is attributed to the fact that usage of carbon dioxide and hydrazine contributes to provision of polysaccharide chain resistance to destruction due to the presence of  end links having structure of metasaccharinic and aldonic acids.The author has developed a new method for pulp obtaining on the basis of the executed investigations  and literature data.  СО2 and hydrazine hydrate have been used for obtaining pulp. Method invention concerns pulp obtaining and it can be used for paper and cardboard package manufacturing in pulp and paper industry.The method is to be carried in the following way: pulp-containing plant raw material is loaded into an autoclave and then aqua solution of sodium monosulfite containing hydrazine hydrate that constitutes 4–5 % of absolute dry pulp-containing raw material mass with liquid module 1:6–1:8 is supplied into the autoclave. The autoclave is closed for operation under pressure and the solution is carbonated under pressure which constitutes 5–8 % of absolute dry plant raw material (shover. Temperature is subsequently raised up to 180 °С in the space of 2 hours and cooking is carried out in the course of 4 hours. Usage of  the proposed method for shover cooking makes it possible to reduce monosulfite cooking process and improve qualitative characteristics and output of the desired product.  In addition to above mentioned fact there is a possibility to improve bleaching and final product output. 

  11. Lifetime obtained by ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Chakaroun, M. [XLIM-MINACOM-UMR 6172, Faculte des Sciences et Techniques, 123 av. Albert Thomas, 87060 Limoges cedex (France); Antony, R. [XLIM-MINACOM-UMR 6172, Faculte des Sciences et Techniques, 123 av. Albert Thomas, 87060 Limoges cedex (France)], E-mail: remi.antony@unilim.fr; Taillepierre, P.; Moliton, A. [XLIM-MINACOM-UMR 6172, Faculte des Sciences et Techniques, 123 av. Albert Thomas, 87060 Limoges cedex (France)

    2007-09-15

    We have fabricated green organic light-emitting diodes based on tris-(8-hydroxyquinoline)aluminium (Alq3) thin films. In order to favor the charge carriers transport from the anode, we have deposited a N,N'-diphenyl-N,N'-bis (3-methylphenyl)-1,1'-diphenyl-4,4'-diamine (TPD) layer (hole transport layer) on a ITO anode. Cathode is obtained with a calcium layer covered with a silver layer. This silver layer is used to protect the other layers against oxygen during the OLED use. All the depositions are performed under vacuum and the devices are not exposed to air during their realisation. In order to improve the silver layer characteristics, we have realized this layer with the ion beam assisted deposition process. The aim of this process is to densify the layer and then reduce the permeation of H{sub 2}O and O{sub 2}. We have used argon ions to assist the silver deposition. All the OLEDs optoelectronic characterizations (I = f(V), L = f(V)) are performed in the ambient air. We compare the results obtained with the assisted layer with those obtained with a classical cathode realized by thermal unassisted evaporation. We have realized lifetime measurements in the ambient air and we discuss about the assisted layer influence on the OLEDs performances.

  12. Nuclear fuel element

    International Nuclear Information System (INIS)

    Penrose, R.T.; Thompson, J.R.

    1976-01-01

    A method of protecting the cladding of a nuclear fuel element from internal attack and a nuclear fuel element for use in the core of a nuclear reactor are disclosed. The nuclear fuel element has disposed therein an additive of a barium-containing material and the barium-containing material collects reactive gases through chemical reaction or adsorption at temperatures ranging from room temperature up to fuel element plenum temperatures. The additive is located in the plenum of the fuel element and preferably in the form of particles in a hollow container having a multiplicity of gas permeable openings in one portion of the container with the openings being of a size smaller than the size of the particles. The openings permit gases and liquids entering the plenum to contact the particles. The additive is comprised of elemental barium or a barium alloy containing one or more metals in addition to barium such as aluminum, zirconium, nickel, titanium and combinations thereof. 6 claims, 3 drawing figures

  13. OBTAINING AND PROPERTIES OF AgInS2 FILMS

    Directory of Open Access Journals (Sweden)

    M. A. Abdullaev

    2016-01-01

    Full Text Available Aim. The aim is to obtain AgInS2 films and study their electrical and optical properties.Methods. The samples of thin AgInS2 films for measurement were obtained by the method of magnetron sputtering with direct current. The structure, phase and elemental composition were studied using DRON-2 X-ray diffractometer (СuKа - radiation and the microscope LEO-1450 with EDS attachment for X-ray microanalysis. The optical transmittance and absorption were examined using MDR-2 monochromator in the wavelength range of 400-800 nm with the Keitley electrometer and FD-10G; we applied the spectral resolution of ± 1 meV. The electrical conductivity, Hall effect was measured by the four-point probe method with indium ohmic contacts. Measurements were carried out in the temperature range of 77-400 K.Findings. We obtained indium disulfide and silver films with the thickness of up to 1 μm on quartz substrates by magnetron sputtering. It is shown that increasing the substrate temperature to about 450 0С allows to obtain single phase film with a chalcopyrite structure with a band gap of 1.88 eV and high absorption coefficient (>104см-1.Conclusions. The possibility of obtaining films in a wide range of the electrical resistance and variation of the electrical parameters at constant stoichiometry is of interest for efficient technologies of phototransduction.

  14. Division algebras with integral elements

    International Nuclear Information System (INIS)

    Koca, M.; Ozdes, N.

    1988-06-01

    Pairing two elements of a given division algebra furnished with a multiplication rule leads to an algebra of higher dimension restricted by 8. This fact is used to obtain the roots of SO(4) and SP(2) from the roots ±1 of SU(2) and the weights ±1/2 of its spinor representation. The root lattice of SO(8) described by 24 integral quaternions are obtained by pairing two sets of roots of SP(2). The root system of F 4 is constructed in terms of 24 integral and 24 ''half-integral'' quaternions. The root lattice of E 8 expressed as 240 integral octonions are obtained by pairing two sets of roots of F 4 . 24 integral quaternions of SO(8) forming a discrete subgroup of SU(2) is shown to be the automorphism group of the root lattices of SO(8), F 4 and E 8 . The roots of maximal subgroups SO(16), E 7 XSU(2), E 6 XSU(3), SU(9) and SU(5)XSU(5) of E 8 are identified with a simple method. Subsets of the discrete subgroup of SU(2) leaving maximal subgroups of E 8 are obtained. Constructions of E 8 root lattice with integral octonions in 7 distinct ways are made. Magic square of integral lattices of Goddard, Nahm, Olive, Ruegg and Schwimmer are derived. Possible physical applications are suggested. (author). 16 refs, 6 figs, 5 tabs

  15. Characterization of Wastewaters obtained from Hatay Tanneries

    Directory of Open Access Journals (Sweden)

    Şana Sungur

    2017-06-01

    Full Text Available The leather tanning industry is one of the most significant pollutants in terms of both conventional and toxic parameters. On the other hand, leather industry has an important economic role both in Turkey and in the World. In this study, wastewater samples were taken from 15 different tanneries in the Hatay Region. Wastewaters obtained from liming process and chromium tanning process was analyzed. Sulfide, chromium (III, chromium (VI, oil and grease, total suspended solids (TSS, organic matters, biochemical oxygen demand (BOD, chemical oxygen demand (COD, pH and alkalinity were determined according to Turkish Standard Methods. The determined averages values belong to wastewaters obtained from liming process were as following: pH 11.71; COD 16821 mg L-1; BOD 4357 mg L-1; TSS 39023 mg L-1; oil and grease 364 mg L-1; S-2 concentration 802 mg L-1; alkalinity 2115 mg L-1. The determined averages values belong to wastewaters obtained from chromium tanning process were also as following: pH 4.23; COD 6740 mg L-1; BOD 377 mg L-1; Cr+3 concentrations 372 mg L-1; Cr+6 concentrations 127 mg L-1; TSS 14553 mg L-1; oil and grease 343 mg L-1. The results of all analyzes were higher than wastewater discharge standards. As a result, it’s necessary to use more effective treatments in order to reduce the negative impacts of leather tanning industry that affect environment, natural water resources and at last human health and welfare.

  16. Propensity for obtaining alcohol through shoulder tapping.

    Science.gov (United States)

    Toomey, Traci L; Fabian, Lindsey E A; Erickson, Darin J; Lenk, Kathleen M

    2007-07-01

    Underage youth often obtain alcohol from adults who illegally provide the alcohol. One method for obtaining alcohol from adults is shoulder tapping, where youth approach an adult outside an alcohol establishment and ask the adult to purchase alcohol for them. The goal of this study was to assess what percentage of the general and youth-targeted adult population approached outside of a convenience/liquor store will agree to purchase and then provide alcohol to individuals who appear under age 21. We conducted 2 waves of pseudo-underage shoulder tap request attempts, using requesters who were age 21 or older but appeared 18 to 20 years old. In both waves, requests were conducted at randomly selected liquor and convenience stores, requesters explained that the reason they were asking the adult was because they did not have their identification with them, and requesters asked the adults to purchase a 6-pack of beer. During wave 1, we conducted 102 attempts, with the requester approaching the first adult entering the store alone. During wave 2, we conducted 102 attempts where the requester approached the first casually dressed male entering the store alone who appeared to be 21 to 30 years old. During wave 1, 8% of the general sample of approached adults provided alcohol to the pseudo-underage requesters. The odds of adults providing alcohol in urban areas were 9.4 times greater than in suburban areas. During wave 2, 19% of the approached young men provided alcohol to the requesters. No requester, request attempt, establishment, or community characteristics were associated with request attempt outcomes during wave 2. A small percentage of the general population of adults will agree to provide alcohol to underage youth when approached outside an alcohol establishment. The likelihood of underage youth obtaining alcohol through shoulder tapping increases substantially if the youth approach young men.

  17. A general scheme for obtaining graviton spectrums

    International Nuclear Information System (INIS)

    GarcIa-Cuadrado, G

    2006-01-01

    The aim of this contribution is to present a general scheme for obtaining graviton spectra from modified gravity theories, based on a theory developed by Grishchuk in the mid 1970s. We try to be pedagogical, putting in order some basic ideas in a compact procedure and also giving a review of the current trends in this arena. With the aim to fill a gap for the interface between quantum field theorists and observational cosmologist in this matter, we highlight two interesting applications to cosmology: clues as to the nature of dark energy; and the possibility of reconstruction of the scalar potential in scalar-tensor gravity theories

  18. Obtaining high purity silica from rice hulls

    Directory of Open Access Journals (Sweden)

    José da Silva Júnior

    2010-01-01

    Full Text Available Many routes for extracting silica from rice hulls are based on direct calcining. These methods, though, often produce silica contaminated with inorganic impurities. This work presents the study of a strategy for obtaining silica from rice hulls with a purity level adequate for applications in electronics. The technique is based on two leaching steps, using respectively aqua regia and Piranha solutions, which extract the organic matrix and inorganic impurities. The material was characterized by Fourier-transform infrared spectroscopy (FTIR, powder x-ray diffraction (XRD, x-ray fluorescence (XRF, scanning electron microscopy (SEM, particle size analysis by laser diffraction (LPSA and thermal analysis.

  19. Diaphragms obtained by radiochemical grafting in PTFE

    International Nuclear Information System (INIS)

    Nenner, T.; Fahrasmane, A.

    1984-01-01

    Diaphragms for alkaline water electrolysis are prepared by radiochemical grafting of PTFE fabric with styrene, which is later on sulfonated, or with acrylic acid. The diaphragms obtained are mechanically resistant to potash at temperatures up to 200 0 C, but show some degrafting, which limits the lifetime. The sulfonated styrene group has been found to be more stable in electrolysis than the acrylic acid. In both cases, the incorporation of a cross-linking agent like divinyl benzene improves the lifetime of the diaphragms. Electrolysis during 500 hours at 120 0 C and 10 kAm 2 could be performed. (author)

  20. Reliability of "Google" for obtaining medical information

    Directory of Open Access Journals (Sweden)

    Mihir Kothari

    2015-01-01

    Full Text Available Internet is used by many patients to obtain relevant medical information. We assessed the impact of "Google" search on the knowledge of the parents whose ward suffered from squint. In 21 consecutive patients, the "Google" search improved the mean score of the correct answers from 47% to 62%. We found that "Google" search was useful and reliable source of information for the patients with regards to the disease etiopathogenesis and the problems caused by the disease. The internet-based information, however, was incomplete and not reliable with regards to the disease treatment.

  1. Burnup measurements of leader fuel elements

    International Nuclear Information System (INIS)

    Henriquez, C; Navarro, G; Pereda, C

    2000-01-01

    Some time ago the CCHEN authorities decided to produce a set of 50 low enrichment fuel elements. These elements were produced in the PEC (Fuel Elements Plant), located at CCHEN offices in Lo Aguirre. These new fuel elements have basically the same geometrical characteristics of previous ones, which were British and made with raw material from the U.S. The principal differences between our fuel elements and the British ones is the density of fissile material, U-235, which was increased to compensate the reduction in enrichment. Last year, the Fuel Elements Plant (PEC) delivered the shipment's first four (4) fuel elements, called leaders, to the RECH1. A test element was delivered too, and the complete set was introduced into the reactor's nucleus, following the normal routine, but performing a special follow-up on their behavior inside the nucleus. This experimental element has only one outside fuel plate, and the remaining (15) structural plates are aluminum. In order to study the burnup, the test element was taken out of the nucleus, in mid- November 1999, and left to decay until June 2000, when it was moved to the laboratory (High Activity Cell), to start the burnup measurements, with a gamma spectroscopy system. This work aims to show the results of these measurements and in addition to meet the following objectives: (a) Visual test of the plate's general condition; (b) Sipping test of fission products; (c) Study of burn-up distribution in the plate; (d) Check and improve the calculus algorithm; (e) Comparison of the results obtained from the spectroscopy with the ones from neutron calculus

  2. Carbon nanofibers obtained from electrospinning process

    Science.gov (United States)

    Bovi de Oliveira, Juliana; Müller Guerrini, Lília; Sizuka Oishi, Silvia; Rogerio de Oliveira Hein, Luis; dos Santos Conejo, Luíza; Cerqueira Rezende, Mirabel; Cocchieri Botelho, Edson

    2018-02-01

    In recent years, reinforcements consisting of carbon nanostructures, such as carbon nanotubes, fullerenes, graphenes, and carbon nanofibers have received significant attention due mainly to their chemical inertness and good mechanical, electrical and thermal properties. Since carbon nanofibers comprise a continuous reinforcing with high specific surface area, associated with the fact that they can be obtained at a low cost and in a large amount, they have shown to be advantageous compared to traditional carbon nanotubes. The main objective of this work is the processing of carbon nanofibers, using polyacrylonitrile (PAN) as a precursor, obtained by the electrospinning process via polymer solution, with subsequent use for airspace applications as reinforcement in polymer composites. In this work, firstly PAN nanofibers were produced by electrospinning with diameters in the range of (375 ± 85) nm, using a dimethylformamide solution. Using a furnace, the PAN nanofiber was converted into carbon nanofiber. Morphologies and structures of PAN and carbon nanofibers were investigated by scanning electron microscopy, Raman Spectroscopy, thermogravimetric analyses and differential scanning calorimeter. The resulting residual weight after carbonization was approximately 38% in weight, with a diameters reduction of 50%, and the same showed a carbon yield of 25%. From the analysis of the crystalline structure of the carbonized material, it was found that the material presented a disordered structure.

  3. Experimental methodology for obtaining sound absorption coefficients

    Directory of Open Access Journals (Sweden)

    Carlos A. Macía M

    2011-07-01

    Full Text Available Objective: the authors propose a new methodology for estimating sound absorption coefficients using genetic algorithms. Methodology: sound waves are generated and conducted along a rectangular silencer. The waves are then attenuated by the absorbing material covering the silencer’s walls. The attenuated sound pressure level is used in a genetic algorithm-based search to find the parameters of the proposed attenuation expressions that include geometric factors, the wavelength and the absorption coefficient. Results: a variety of adjusted mathematical models were found that make it possible to estimate the absorption coefficients based on the characteristics of a rectangular silencer used for measuring the attenuation of the noise that passes through it. Conclusions: this methodology makes it possible to obtain the absorption coefficients of new materials in a cheap and simple manner. Although these coefficients might be slightly different from those obtained through other methodologies, they provide solutions within the engineering accuracy ranges that are used for designing noise control systems.

  4. Alcoholic Beverages Obtained from Black Mulberry

    Directory of Open Access Journals (Sweden)

    Jacinto Darias-Martín

    2003-01-01

    Full Text Available Black mulberry (Morus nigra is a fruit not known only for its nutritional qualities and its flavour, but also for its traditional use in natural medicine as it has a high content of active therapeutic compounds. However, this fruit is not widely produced in Spain but some trees are still found growing in the Canary Islands, particularly on the edges of the ravine. The inhabitants of these islands (Tenerife, La Gomera, La Palma, El Hierro and Lanzarote collect the fruit and prepare homemade beverages for medicinal purposes. Numerous authors have reported that type II diabetes mellitus can be controlled by taking a mixture containing black mulberry and water. Apart from that, this fruit has been used for the treatment of mouth, tongue and throat inflammations. In this study we present some characteristics of black mulberry juice (TSS, pH, titratable acidity, citric acid, lactic acid, polyphenols, anthocyanins, the potassium etc. and alcoholic beverages (alcoholic grade, pH, total acidity, volatile acidity, tannins, phenols etc. obtained from black mulberry. Moreover, we have studied the quality of liquors obtained from black mulberry in Canary Islands.

  5. Cotton nanofibers obtained by different acid conditions

    International Nuclear Information System (INIS)

    Teixeira, Eliangela de M.; Oliveira, Caue Ribeiro de; Mattoso, Luiz H.C.; Correa, Ana Carolina; Palladin, Priscila

    2009-01-01

    The thermal stability of cellulose nanofibers is related to their application and especially to polymer processing which temperatures of processing are around 200 deg C. In this work, nanofibers of commercial cotton were obtained by acid hydrolysis employing different acids: sulfuric, hydrochloric and a mixture (2:1; sulfuric acid: hydrochloric acid).The morphology of the nanofibers were characterized by transmission microscopy (TEM), crystallinity by x-ray diffraction (XRD) and thermal stability in air atmosphere by thermogravimetric analysis (TGA). The results indicated a very similar morphology and crystallinity among them. The main differences were relative to aggregation state e and thermal stability. The aggregation state of the suspensions decreases in the order HCl 2 SO 4 :HCl 2 SO 4- . The hydrolysis with a mix of HCl and H 2 SO 4 resulted in cellulose nanofibers with higher thermal stability than those hydrolyzed with H 2 SO 4 . The hydrolysis employed with a mixture of sulphuric and hydrochloric acids also showed a better dispersion than those suspensions of nanofibers obtained by hydrolysis with only HCl. (author)

  6. Strong beam production for some elements

    International Nuclear Information System (INIS)

    Camplan, J.; Chaumont, J.; Meunier, R.

    1974-01-01

    Three electromagnetic isotope separators are installed in Rene Bernas Laboratory, one being especially adapted to ion implantation. The three apparatus use the same type of ion source and system of beam extraction. The special ion source is distinguishable from the others only by its smaller dimensions. These sources allow strong currents to be obtained for almost every element. The source and its extraction system are briefly described, examples of beams obtained are given [fr

  7. A computer program for structural analysis of fuel elements

    International Nuclear Information System (INIS)

    Hayashi, I.M.V.; Perrotta, J.A.

    1988-01-01

    It's presented the code ELCOM for the matrix analysis of tubular structures coupled by rigid spacers, typical of PWR's fuel elements. The code ELCOM makes a static structural analysis, where the displacements and internal forces are obtained for each structure at the joints with the spacers, and also, the natural frequencies and vibrational modes of an equivalent integrated structure are obtained. The ELCOM result is compared to a PWR fuel element structural analysis obtained in published paper. (author) [pt

  8. A K/Ka band radiating element for Tx/Rx phased array

    KAUST Repository

    Sandhu, Ali Imran; Arnieri, E.; Amendola, G.; Boccia, L.; Meniconi, E.; Ziegler, V.

    2017-01-01

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  9. A K/Ka band radiating element for Tx/Rx phased array

    KAUST Repository

    Sandhu, Ali Imran

    2017-01-20

    The paper presents a K/Ka band radiating element for TX/RX phased arrays. Dual band operations is obtained using a single radiating surface: a novel radiator is adopted and placed in a configuration in which dual band and single band elements are interleaved. The array elements are optimized to scan the beam in excess of 50° in both bands. A subarray with 49 Rx elements and 105 Tx elements was built and measured confirming the results obtained in simulations.

  10. Data sheets on selected toxic elements

    International Nuclear Information System (INIS)

    Jaworski, J.F.

    1982-01-01

    The chemical elements considered in this volume have been identified as toxic to animal and vegetable life forms; however, these elements have not been studied as intensely as lead, mercury, cadmium, etc. Since, in most cases, existing data are insufficient to permit discussion and comparisons of relative quality, it was decided to present what quantitative data there are in as concise a manner as possible. The resulting data sheets present what is considered to be the best available information on the environmental levels, emissions and toxicology of these elements and some of their compounds. Reference is made to the article or review in which the datum appears and which may contain any discussion of the datum and the methods whereby it was obtained. Elements considered in this volume are antimony, barium, beryllium, bismuth, boron, cesium, gallium, germanium, indium, molybdenum, silver, tellurium, thallium, tin, uranium and zirconium

  11. Elemental analysis with external-beam PIXE

    Science.gov (United States)

    Lin, E. K.; Wang, C. W.; Teng, P. K.; Huang, Y. M.; Chen, C. Y.

    1992-05-01

    A beamline system and experimental setup has been established for elemental analysis using PIXE with an external beam. Experiments for the study of the elemental composition of ancient Chinese potsherds (the Min and Ching ages) were performed. Continuum X-ray spectra from the samples bombarded by 3 MeV protons have been measured with a Si(Li) detector. From the analysis of PIXE data, the concentration of the main elements (Al, Si, K, and Ca) and of more than ten trace elements in the matrices and glazed surfaces were determined. Results for two different potsherds are presented, and those obtained from the glaze colorants are compared with the results of measurements on a Ching blue-and-white porcelain vase.

  12. Multi Elemental Study Using Prompt Gamma Technique

    International Nuclear Information System (INIS)

    Normanshah Dahing; Muhamad Samudi Yasir; Normanshah Dahing; Hanafi Ithnin; Mohd Fitri Abdul Rahman; Hearie Hassan

    2016-01-01

    In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10x10x10 cm 3 and 15x15x15 cm 3 were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with computer simulation, NAA and XRF as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed. (author)

  13. Fuel element transport container

    International Nuclear Information System (INIS)

    Benna, P.; Neuenfeldt, W.

    1979-01-01

    The reprocessing system includes a large number of waterfilled ponds next to each other for the intermediate storage of fuel elements from LWR's. The fuel element transport device is allocated to a middle pond. The individual ponds are separated from each other by walls, and are only accessible from the middle pond via narrow passages. The transport device includes a telescopic running rail for a trolley with a grab device for the fuel element. The running rail is supported in turn by a second trolley, which can be moved by wheels on rails. Part of the drive of the first trolley is arranged on the second one. Using this transport device, adjacent ponds can be served through the passage openings. (DG) [de

  14. Nuclear fuel element

    International Nuclear Information System (INIS)

    Hirayama, Satoshi; Kawada, Toshiyuki; Matsuzaki, Masayoshi.

    1980-01-01

    Purpose: To provide a fuel element for reducing the mechanical interactions between a fuel-cladding tube and the fuel element and for alleviating the limits of the operating conditions of a reactor. Constitution: A fuel element having mainly uranium dioxide consists of a cylindrical outer pellet and cylindrical inner pellet inserted into the outer pellet. The outer pellet contains two or more additives selected from aluminium oxide, beryllium oxide, magnesium oxide, silicon oxide, sodium oxide, phosphorus oxide, calcium oxide and iron oxide, and the inner pellet contains nuclear fuel substance solely or one additive selected from calcium oxide, silicon oxide, aluminium oxide, magnesium oxide, zirconium oxide and iron oxide. The outer pellet of the fuel thus constituted is reduced in mechanical strength and also in the mechanical interactions with the cladding tube, and the plastic fluidity of the entire pellet is prevented by the inner pellet increased in the mechanical strength. (Kamimura, M.)

  15. Creativity Management Key Elements

    Directory of Open Access Journals (Sweden)

    Rosa María Fuchs Ángeles

    2015-09-01

    Full Text Available Organizations are constantly looking towards innovation. In order to reach it they must foment creativity. This paper analyzes a series of elements considered in the organizational creativity management and proposes a model with the indispensable factors that organizations should consider to reach it. These elements are: culture and organizational environment, strategy, structure, communication, relation with customers, human resources (recruiting, training, job design, compensation, promotion, and performance evaluation, long term orientation and the organizational life cycle. Having the analysis of those elements as a basis, the indispensable pillars on management creativity are identified. The proposed model is based on 5 pillars: the alignment between strategic, culture and organizational structure, called by the authors 'Holy Trinity'; intern publicity; customer’s voice; recognition and a look towards future. Finally, the case of an innovative Peruvian enterprise is presented from the model’s perspective and the study conclusions.

  16. Fuel Element Technical Manual

    Energy Technology Data Exchange (ETDEWEB)

    Burley, H.H. [ed.

    1956-08-01

    It is the purpose of the Fuel Element Technical Manual to Provide a single document describing the fabrication processes used in the manufacture of the fuel element as well as the technical bases for these processes. The manual will be instrumental in the indoctrination of personnel new to the field and will provide a single data reference for all personnel involved in the design or manufacture of the fuel element. The material contained in this manual was assembled by members of the Engineering Department and the Manufacturing Department at the Hanford Atomic Products Operation between the dates October, 1955 and June, 1956. Arrangement of the manual. The manual is divided into six parts: Part I--introduction; Part II--technical bases; Part III--process; Part IV--plant and equipment; Part V--process control and improvement; and VI--safety.

  17. Ab initio work function of elemental metals

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Rosengaard, N. M.

    1992-01-01

    We have used a recently developed self-consistent Green’s-function technique based on tight-binding linear-muffin-tin-orbital theory to calculate the work function for the close-packed surfaces of 37 elemental metals. The results agree with the limited experimental data obtained from single cryst...

  18. Polypropylene obtained through zeolite supported catalysts

    International Nuclear Information System (INIS)

    Bastos, Queli C.; Marques, Maria de Fatima V.

    2004-01-01

    Propylene polymerizations were carried out with φ 2 C(Flu)(Cp)ZrCl 2 and SiMe 2 (Ind)2ZrCl 2 catalysts supported on silica, zeolite sodic mordenite (NaM) and acid mordenite (HM). The polymerizations were performed at different temperatures and varying aluminium/zirconium molar ratios ([Al]/[Zr]). The effect of these reaction parameters on the catalyst activity was investigated using a proposed statistical experimental planning. In the case of f 2 C(Flu)(Cp)ZrCl 2 , SiO 2 and NaM were used as support and the catalyst performance evaluated using toluene and pentane as polymerization solvent. The molecular weight, molecular weight distribution, melting point and crystallinity of the polymers were examined. The results indicate very high activities for the syndiospecific heterogeneous system. Also, the polymers obtained had superior Mw and stereo regularity. (author)

  19. Polypropylene obtained through zeolite supported catalysts

    Directory of Open Access Journals (Sweden)

    Queli C. Bastos

    2004-01-01

    Full Text Available Propylene polymerizations were carried out with f2C(Flu(CpZrCl2 and SiMe2(Ind2ZrCl2 catalysts supported on silica, zeolite sodic mordenite (NaM and acid mordenite (HM. The polymerizations were performed at different temperatures and varying aluminium/zirconium molar ratios ([Al]/[Zr]. The effect of these reaction parameters on the catalyst activity was investigated using a proposed statistical experimental planning. In the case of f2C(Flu(CpZrCl2, SiO2 and NaM were used as support and the catalyst performance evaluated using toluene and pentane as polymerization solvent. The molecular weight, molecular weight distribution, melting point and crystallinity of the polymers were examined. The results indicate very high activities for the syndiospecific heterogeneous system. Also, the polymers obtained had superior Mw and stereoregularity.

  20. Process to Obtain Quick Counts from PREP

    Directory of Open Access Journals (Sweden)

    Martínez–Cruz M.Á.

    2011-10-01

    Full Text Available Considering the Preliminary Electoral Results Program (PERP as a database of the federal elections for president of the Mexican Republic, a methodology was developed in order to find representative samples of ballot boxes installed in the election’s day (quick count in different hours, due to its characteristics of gathering of information, the PREP in the first hours forms a non-representative sample of data. In a particular way, in the election of July 2, 2006, after 3 hours of opening the PREP, it was observed that the accuracy of the process of the quick counts was better than the one obtained by the IFE. Among other things, this allows to lower the cost, to increase the confidentiality of the ballot boxes used in the sampling and to distinguish in a precise moment the winning candidate long before PREP finishes.

  1. The method of obtaining of decorative varnish

    International Nuclear Information System (INIS)

    Salidzhanova, N.S.; Tashbekova, D.M.

    1997-01-01

    The method of obtaining of decorative varnish allowing to remove inhibition action of air oxygen and to improve the varnish hardness is described. It is includes the impregnation of texture paper with mixture of PE-284 type polyether lacquer on the basis of unsaturated oligoethylenglycolfumarath resin and cation type salt, putting it on wooden or asbestos cement slabs and further hardening by pulsed beams of accelerated electrons on moving belt. The radiation dose for one pulse is 1,10 -2 - 9,10 -3 MGy, the number of pulses is 180 - 250, the duration of pulses is 2.3 ms, their frequency is 50 KHz. Chloride, bromide, benzylbromide or iodide of N, N-dialkylaminoethyl (benzil) (met)acrylate are used as cation type salt. (author)

  2. Devices for obtaining information about radiation sources

    International Nuclear Information System (INIS)

    Tosswill, C.H.

    1981-01-01

    The invention provides a sensitive, fast, high-resolution device for obtaining information about the distribution of gamma and X-radiation sources and provides a radiation detector useful in such a device. It comprises a slit collimator with a multiplicity of slits each with slit-defining walls of material and thickness to absorb beam components impinging on them. The slits extend further in one transverse direction than the other. The detector for separately detecting beam components passing through the slits also provides data output signals. It comprises a plurality of radiation transducing portions, each at the end of a slit. A positioner changes the transverse position of the slits and radiation transducer (a photoconductor) relative to the source. Applications are in nuclear medicine and industry. Full details and preferred embodiments are given. (U.K.)

  3. Obtaining the electrostatic screening from first principles

    International Nuclear Information System (INIS)

    Shaviv, N.J.; Shaviv, G.

    2003-01-01

    We derive the electrostatic screening effect from first principles and show the basic properties of the screening process. We in particular show that under the conditions prevailing in the Sun the number of particles in the Debye sphere is of the order of unity. Consequently; fluctuations play a dominant role in the screening process. The fluctuations lead to an effective time dependent potential. Particles with low kinetic energy lose on the average energy to the plasma and vice versa with high energy particles. We derive general conditions on the screening energy and show under what conditions the Salpeter approximation is obtained. The connection between the screening and relaxation processes in the plasma is exposed

  4. ORIENTATION OF ENTERPRISES TOWARD OBTAINING COMPETITIVE

    Directory of Open Access Journals (Sweden)

    PAUL BOGDAN ZAMFIR

    2015-10-01

    Full Text Available In this paper I proposed to emphasize the importance of obtaining competitive advantage by companies on EU internal market. The huge EU market, offers for participating companies the possibility to achieve significant economies of scale and numerous niches (segments market, which can be covered with large quantities of goods, the condition is that niches to be discovered in time, and the firms to be able to adapt promptly at their needs. Thus, the most important positive effect derives from the fact that companies have at their disposal a vast market consisting approximately 500 million consumers, free of customs duties and other restrictions inhindering the movement of goods. On this background, the companies can achieve high series production and thereby can reduce their cost of production and increase their competitiveness. In this context, the companies must meet the standards of the European Union, if they really want to gain competitive advantage on EU market.

  5. Elements of social security

    DEFF Research Database (Denmark)

    Hansen, Hans

    Elements of Social Security is a comparative study of important elements of the social security systems in Denmark (DK), Sweden (S), Finland (FIN), Austria (A), Germany (D), the Netherlands (NL), Great Britain (GB) and Canada (CAN). It should be emphasized that Germany is the former West Germany...... (Alte Länder). This is the 9th and last edition of the publication,covering income levels and rules for social security and personal taxation for 1999. Basis for the projections to 1999 income levels is the 1998 data (in some cases 1999 data)for OECD's Taxing Wages as reported by national experts....

  6. Elements of linear space

    CERN Document Server

    Amir-Moez, A R; Sneddon, I N

    1962-01-01

    Elements of Linear Space is a detailed treatment of the elements of linear spaces, including real spaces with no more than three dimensions and complex n-dimensional spaces. The geometry of conic sections and quadric surfaces is considered, along with algebraic structures, especially vector spaces and transformations. Problems drawn from various branches of geometry are given.Comprised of 12 chapters, this volume begins with an introduction to real Euclidean space, followed by a discussion on linear transformations and matrices. The addition and multiplication of transformations and matrices a

  7. Bibliography on transuranium elements

    International Nuclear Information System (INIS)

    Sood, D.D.

    1991-01-01

    A selective bibliography of prominent publications on transuranium elements is compiled. Heading papers, symposia proceedings and the textbooks are included in the bibliography. The bibliography is arranged under the headings: (1)Books, Symposia Proceedings, Reviews etc., (2)Discovery, (3)Weighable Isolation, (4)Metal Preparation, (5)Nuclear Properties, (6)Plutonium as Reactor Fuel, (7)Fuel Reprocessing, (8)Solid State Chemistry, Thermochemistry and Spectroscopy, (9)Radiation Safety, (10)Applications, and (11)Some Typical Indian Papers. Total number of references cited are 298. The bibliography, though selective, will serve as a starting point for comprehensive literature search on transuranium elements. (author)

  8. Finite elements and approximation

    CERN Document Server

    Zienkiewicz, O C

    2006-01-01

    A powerful tool for the approximate solution of differential equations, the finite element is extensively used in industry and research. This book offers students of engineering and physics a comprehensive view of the principles involved, with numerous illustrative examples and exercises.Starting with continuum boundary value problems and the need for numerical discretization, the text examines finite difference methods, weighted residual methods in the context of continuous trial functions, and piecewise defined trial functions and the finite element method. Additional topics include higher o

  9. Boiling points of the superheavy elements 117 and 118

    International Nuclear Information System (INIS)

    Takahashi, N.

    2001-01-01

    It has been shown that the relativistic effect on the electrons reveal in the heavy element region. What kind of changes will appear in the heavy elements because of the relativistic effects? Can we observe the changes? We observed that the boiling points of astatine and radon are lower than that extrapolated values from lighter elements in the same groups. Systematic behavior of the elements on the boiling point was examined and a new method for the estimation of the boiling points of the superheavy elements in the halogen and rare gases has been found. The estimated values of the elements 117 and 118 are 618 and 247 K, respectively which are considerably lower than those obtained until now. If these values are correct the production of the superheavy elements with heavy ions reaction may be affected. Further, the chemical properties may be fairly different from the lighter elements. (author)

  10. Determination of refractory trace elements in Chinese meteorites by RNAA

    International Nuclear Information System (INIS)

    Kraehenbuehl, U.; Burger, M.

    1989-01-01

    Some refractory trace elements are important target elements for spallation reactions in meteorites. These elements also serve to characterize the investigated meteorites. The elements Ti, Y, Zr, Hf, W and Ta were measured after radiochemical separation in chondrites from China. After acid digestion of the irradiated samples, the group separations were obtained by precipitation reactions. The necessary radiochemical purification of the pure β emitter Y was realized on a Lewatite OC 1026 column. For all the other elements discrete gamma radiation was measured. (orig.)

  11. Multi-element determination of soil solution by INAA

    International Nuclear Information System (INIS)

    Qian Qinfang; Wu Shuiqing; Tian Jibing

    1992-01-01

    One of the factors influencing crop growth is the effective elemental contents, especially trace elements, under the circumstances of the same concentrations of N, P and K in soil. In order to obtain the data of effective elemental contents in soil, a novel method was introduced. In this method, soil solution was extracted by a squeezer. The concentrations of elements in soil solution were determined by INAA. Study on the compositions and the contents of elements in soil solution will provide information on making a suitable soil environment for plant growth and on rational and economical manuring

  12. Biodegradable Polyelectrolyte Obtained by Radiation Polymerization

    International Nuclear Information System (INIS)

    Craciun, G.; Martin, D.; Manaila, E.; Nemtanu, M.; Brasoveanu, M.; Ighigeanu, D.

    2009-01-01

    Poly electrolytes are water-soluble polymers carrying ionic charge along the polymer chain. Depending upon the charge, these polymers are anionic or cationic. The inherent solid - liquid separating efficiency makes these poly electrolytes a unique class of polymers which find extensive application in potable water, industrial raw and process water, municipal sewage treatment, mineral processing and metallurgy, oil drilling and recovery, etc. Also, due to their ability to produce advanced induced coagulation, a considerable amount of bacteria and viruses are precipitated together with the suspended solids. Especially the acrylamide polymers are very efficacious for water treatment but acrylamide is a toxic monomer and therefore their use are governed by international standards that provide the residual acrylamide monomer content (RAMC) in them be less than 0.05%. Under these circumstances our attention was focused on the following research steps that are presented in this paper: 1) Preparation of a special class of poly electrolytes, named Pn, with very low RAMC values, based on electron beam (EB), microwave (MW) and EB + MW induced co-polymerization of aqueous solutions containing appropriate mixtures of acrylamide (AMD) and acrylic acid (AA) monomers (AMD - AA co-polymers). The Pn were obtained by radiation technology with very small RAMC (under 0.01%) as well as in a wide range of molecular weights and charge densities. Very low AMD monomer content of Pn is due to the major advantages of radiation induced polymerization in aqueous solution containing monomers. Due to water presence in the EB irradiated system, irradiated water radicals facilitate the polymerization process and increase rate and level of monomers conversion in co-polymers. Also, once again, by the presence of water, which absorbs MW energy very strongly, the MW polymerization reaction rate is much enhanced resulting in a reaction time about 50-100 times lowers than by conventional heating. Also

  13. Elements of Social Security

    DEFF Research Database (Denmark)

    Hansen, Hans

    Elements of Social Security contains an overview of important benefit schemes in Denmark, Sweden, Finland, Austria, Germany, the Netherlands, Great Britain and Canada. The schemes are categorized according to common sets of criteria and compared. Stylized cases illustrate the impact on disposable...

  14. Elements of Social Security

    DEFF Research Database (Denmark)

    Hansen, Hans

    Elements of Social Security contains an overview of important benefit schemes in Denmark, Sweden, Finland, Germany, the Netherlands, Great Britain and Canada. The schemes are categorized according to common sets of criteria and compared. Stylized cases illustrate the impact on disposable income...

  15. Elements of Social Security

    DEFF Research Database (Denmark)

    Hansen, Hans

    Elements of Social Security contains an overview of important benefit schemes in Denmark, Sweden, Finland, Germany, Great Britain, the Netherlands and Canada. The schemes are categorized according to common sets of criteria and compared. Stylized cases illustrate the impact on disposable income...

  16. Water, the intangible element

    NARCIS (Netherlands)

    Schotting, R.J.

    2009-01-01

    Water is the key to life. No living creature can survive without water. Too much water or polluted water are serious threats to mankind. Managing this intangible element is complex, not only in wet deltaic regions but also in the (semi-)arid regions of the world. Combined efforts of the

  17. Movies and Literary Elements.

    Science.gov (United States)

    Keller, Rodney D.

    1987-01-01

    Recommends using movie clips to stimulate students' interest in reading a novel as well as to teach elements of fiction such as plot, character, setting, symbol, irony, and theme. Describes each clip and provides study questions. Includes a listing of movies made from books. (NH)

  18. Elements of Architecture

    DEFF Research Database (Denmark)

    Elements of Architecture explores new ways of engaging architecture in archaeology. It conceives of architecture both as the physical evidence of past societies and as existing beyond the physical environment, considering how people in the past have not just dwelled in buildings but have existed...

  19. Inside finite elements

    CERN Document Server

    Weiser, Martin

    2016-01-01

    All relevant implementation aspects of finite element methods are discussed in this book. The focus is on algorithms and data structures as well as on their concrete implementation. Theory is covered as far as it gives insight into the construction of algorithms. Throughout the exercises a complete FE-solver for scalar 2D problems will be implemented in Matlab/Octave.

  20. Plants' essential chemical elements

    Science.gov (United States)

    Kevin T. Smith

    2007-01-01

    Every garden center and hardware store sells fertilizer guaranteed to "feed" plants. In a strict sense, we can't feed plants. Food contains an energy source. Green plants capture solar energy and make their own food through photosynthesis! Photosynthesis and other metabolic processes require chemical elements in appropriate doses for plants to survive...

  1. Elements of relativity theory

    International Nuclear Information System (INIS)

    Lawden, D.F.

    1985-01-01

    The book on elements of relativity theory is intended for final year school students or as an early university course in mathematical physics. Special principle of relativity, lorentz transformation, velocity transformations, relativistic mechanics, and general theory of relativity, are all discussed. (U.K.)

  2. Photovoltaic radiation detector element

    International Nuclear Information System (INIS)

    Agouridis, D.C.

    1980-01-01

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein in the edge of which closely approaches but is spaced from the current collector strips

  3. HOW TO OBTAIN BOOKS FOR YOUR GROUP

    CERN Multimedia

    Head Librarian

    2000-01-01

    The wide variety of scientific and technical activity engaged in by people working at CERN means that the Library cannot always provide a deep on-site coverage in areas which are outside the core subjects of particle physics and accelerators. As many of you have already experienced, one way of solving this is to borrow books from other libraries. Our Inter-Library Loan (ILL) service currently obtains about 1000 books on loan per year for readers at CERN. However, there may be books which groups need on a more permanent basis, in which case a loan from either our own collection or via ILL is not the appropriate solution. Instead, groups might prefer to purchase such books from their own budgets. To facilitate this, the CERN Library has set up a procedure with the SPL Division, by which you can submit your purchase request to us and be charged via a TID when you receive the book. In addition, via our database interface WebLib, we can provide you with a private virtual catalogue of your group's collection, which...

  4. Evaluation of biodiesel obtained from cottonseed oil

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Umer [Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad-38040 (Pakistan); Department of Industrial Chemistry, Government College University, Faisalabad-38000 (Pakistan); Anwar, Farooq [Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad-38040 (Pakistan); Knothe, Gerhard [United States Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, IL 61604 (United States)

    2009-09-15

    Esters from vegetable oils have attracted a great deal of interest as substitutes for petrodiesel to reduce dependence on imported petroleum and provide a fuel with more benign environmental properties. In this work biodiesel was prepared from cottonseed oil by transesterification with methanol, using sodium hydroxide, potassium hydroxide, sodium methoxide and potassium methoxide as catalysts. A series of experiments were conducted in order to evaluate the effects of reaction variables such as methanol/oil molar ratio (3:1-15:1), catalyst concentration (0.25-1.50%), temperature (25-65 C), and stirring intensity (180-600 rpm) to achieve the maximum yield and quality. The optimized variables of 6:1 methanol/oil molar ratio (mol/mol), 0.75% sodium methoxide concentration (wt.%), 65 C reaction temperature, 600 rpm agitation speed and 90 min reaction time offered the maximum methyl ester yield (96.9%). The obtained fatty acid methyl esters (FAME) were analyzed by gas chromatography (GC) and {sup 1}H NMR spectroscopy. The fuel properties of cottonseed oil methyl esters (COME), cetane number, kinematic viscosity, oxidative stability, lubricity, cloud point, pour point, cold filter plugging point, flash point, ash content, sulfur content, acid value, copper strip corrosion value, density, higher heating value, methanol content, free and bound glycerol were determined and are discussed in the light of biodiesel standards such as ASTM D6751 and EN 14214. (author)

  5. Electrolytic Hydrogen obtaining by a photovoltaic source

    International Nuclear Information System (INIS)

    Pasculete, E.; Condrea, F.; Stanoiu, L.

    2005-01-01

    At present, the developed countries allocate large funds for the financing of some global programs for fundamental and applicative research for development of hydrogen non-conventional production technologies. One of these technologies is the photo-assisted electrolysis. This technology is adopted in the research, which results are presented in this paper. The experimental model includes as basic equipment 100 W photovoltaic source, electrolysis battery press filter type, control unit of the electric energy discharged, accumulator, hydrogen storage unit. Five types of material have been tested for the electrolysis cell diaphragm: asbestos; Netrom- unwoven material from fibers of polypropylene; ion changing composite membrane - polysulfone support with an active layer of sulfonated poly-sulfone (PSS/PSJ) and poly-sulfone support with an active layer of sulfonated poly-eter cetone (SPEEK/PSf); ion-exchange membrane made from sulfonated poly-eter cetone (SPEEK). The graphics and results from the test system are presented. The analysis of the experimental results lead to the establishment of the optimal configuration of battery and of the operational conditions of the assembly. The experimental results give the opportunity to obtain electrolytic hydrogen with a photovoltaic source, in an efficient system, and promote the Romanian research at a level of a demonstrative installation

  6. WAYS OF OBTAINING FINANCING BY TOUR OPERATORS

    Directory of Open Access Journals (Sweden)

    CARLAN ADRIANA

    2015-12-01

    Full Text Available domanin.Romania is a country with highly touristic potential that is not exploited to maximum. In order to reach a high quality level of tourism permanent development and modernization are needed and also the establishment of new businesses That conducts other activities other than those which takes place in our country. Ways of getting funds are multiple, depending on individual needs.To develop tourism activities it is necessary to require some funding that can come from various sources: auto-financing, loans from various banks or from third parties and grants offered by the European Union. There are many programs designed to support the development of tourism, such as ROP that allows people to access grants in order to implement projects for the establishment and the development of the activity in the touristic field. The purpose of this article is to highlight funding opportunities for the tourism operators and to assist them in choosing the appropriate form of financing of the current activity or the activity they want to implement in the future and description of how to obtain the necessary funds from various sources.

  7. Shielding design to obtain compact marine reactor

    International Nuclear Information System (INIS)

    Yamaji, Akio; Sako, Kiyoshi

    1994-01-01

    The marine reactors equipped in previously constructed nuclear ships are in need of the secondary shield which is installed outside the containment vessel. Most of the weight and volume of the reactor plants are occupied by this secondary shield. An advanced marine reactor called MRX (Marine Reactor X) has been designed to obtain a more compact and lightweight marine reactor with enhanced safety. The MRX is a new type of marine reactor which is an integral PWR (The steam generator is installed in the pressure vessel.) with adopting a water-filled containment vessel and a new shielding design method of no installation of the secondary shield. As a result, MRX is considerably lighter in weight and more compact in size as compared with the reactors equipped in previously constructed nuclear ships. For instance, the plant weight and volume of the containment vessel of MRX are about 50% and 70% of those of the Nuclear Ship MUTSU, in spite of the power of MRX is 2.8 times as large as the MUTSU's reactor. The shielding design calculation was made using the ANISN, DOT3.5, QAD-CGGP2 and ORIGEN codes. The computational accuracy was confirmed by experimental analyses. (author)

  8. Obtaining cementitious material from municipal solid waste

    Directory of Open Access Journals (Sweden)

    Macías, A.

    2007-06-01

    Full Text Available The primary purpose of the present study was to determine the viability of using incinerator ash and slag from municipal solid waste as a secondary source of cementitious materials. The combustion products used were taken from two types of Spanish MSW incinerators, one located at Valdemingómez, in Madrid, and the other in Melilla, with different incineration systems: one with fluidised bed combustion and other with mass burn waterwall. The effect of temperature (from 800 to 1,200 ºC on washed and unwashed incinerator residue was studied, in particular with regard to phase formation in washed products with a high NaCl and KCl content. The solid phases obtained were characterized by X-ray diffraction and BET-N2 specific surface procedures.El principal objetivo del trabajo ha sido determinar la viabilidad del uso de las cenizas y escorias procedentes de la incineración de residuos sólidos urbanos, como materia prima secundaria para la obtención de fases cementantes. Para ello se han empleado los residuos generados en dos tipos de incineradoras españolas de residuos sólidos urbanos: la incineradora de Valdemingómez y la incineradora de Melilla. Se ha estudiado la transformación de los residuos, sin tratamiento previo, en función de la temperatura de calentamiento (desde 800 ºC hasta 1.200 ºC, así como la influencia del lavado de los residuos con alto contenido en NaCl y KCl en la formación de fases obtenidas a las diferentes temperaturas de calcinación. Las fases obtenidas fueron caracterizadas por difracción de rayos X y área superficial por el método BET-N2.

  9. Reduced sensitivity RDX obtained from bachmann RDX

    Energy Technology Data Exchange (ETDEWEB)

    Spyckerelle, Christian; Eck, Genevieve [EURENCO France, Sorgues Plant 1928 route d' Avignon, BP 311, 84706 Sorgues Cedex (France); Sjoeberg, Per; Amneus, Anna-Maria [EURENCO Sweden, SE-69186 Karlskoga (Sweden)

    2008-02-15

    In recent years much interest has been generated in a quality of reduced sensitivity RDX (RS-RDX), like I-RDX {sup registered} which, when incorporated in cast cure and even pressable plastic bonded explosives (PBX compositions), can confer reduced shock sensitivity as measured through gap test. At crystal level, lot of work has been done to try to determine which property or properties may explain the behaviour of the corresponding cast PBX composition. But up to now, and despite an international inter-laboratory comparison (Round Robin) of seven lots of RDX from five different manufacturers conducted from 2003 to 2005, even if some techniques lead to interesting results, there is no dedicated specification to apply to RS-RDX. This quality (I-RDX {sup registered}) has proved to retain its low sensitivity even after ageing, which does not seem to be the case for standard RDX produced by the Bachmann process (when re-crystallized under I-RDX conditions in order to obtain RS-RDX). It has been shown that the higher sensitivity of RDX produced by the Bachmann process, or the evolution of sensitivity after ageing of RS-RDX produced from Bachmann RDX may be linked to the presence of octogen (HMX) during the crystallization process. In order to check such hypothesis, low HMX content RDX produced by the Bachmann process has been prepared and evaluated in cast PBX composition (PBX N 109). Results of the characterization of such quality of RDX and its evaluation in cast PBX composition as well as ageing behaviour are presented and discussed; there are indications that removal of HMX from Bachmann RDX may lead to RS-RDX, which retains its RS character even after ageing. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  10. Photodisintegration of the heavy elements

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, R W; Collie, C H

    1950-08-01

    The photothresholds for the emission of neutrons by the following elements have been determined; the threshold in MeV is given in the brackets following the symbol: Pt(6.1 +- 0.1), Au(8.1 +- 0.1), Hg(6.6 +- 0.2), Tl(7.3 +- 0.25), Pb(6.9 +- 0.1), Bi(7.2 +- 0.1), Th(6.9 +- 0.15), U(5.8 +- 0.15). The neutrons were detected by the Szilard-Chalmers method of chemical concentration and the ..gamma.. rays were obtained from a small betatron. Rough values of the total cross sections can be estimated from the results.

  11. Tin dioxide nanostructured thin films obtained through polymeric precursor method

    Directory of Open Access Journals (Sweden)

    Marcelo Antônio Dal Santos

    2012-11-01

    Full Text Available Tin dioxide (SnO2 nanostructured thin films with low proportion of defects and low roughness were produced through the systematic control of temperature and viscosity of the precursor solutions used for thin films deposition. These solutions were obtained through the citrate method and the films were deposited through the ‘dip-coating’ technique on glass substrate and after thermal treatment at 470ºC/4h, they were characterized both structurally and morphologically through the X-ray diffractometry, optic microscopy, scanning electronic microscopy, atomic force microscopy, X-ray fluorescence, UV-Vis absorption spectroscopy and X-ray excited photoelectrons spectroscopy. The film thickness was obtained through scanning electronic microscopy of the films cross-section and correlated to the proportion of Sn and Si obtained through X-ray fluorescence. X-ray diffractometry of the films revealed the presence of peaks corresponding to the SnO2 crystalline phase, overlapping a wide peak between 20 and 30º (2?, characteristic of the glass substrate. Optic microscopy, Scanning electronic microscopy and atomic force microscopy revealed homogeneous films, with low roughness, suitable to several applications such as sensors and transparent electrodes. It could be observed through the UV-Vis absorption analysis that the films presented high optical transparency and ‘band gap’ energy 4.36 eV. The X-ray excited photoelectron spectroscopy confirmed the presence of SnO2, as well as traces of the elements present in the glass substrate and residual carbon from the thermal treatment of the films.

  12. Element-topology-independent preconditioners for parallel finite element computations

    Science.gov (United States)

    Park, K. C.; Alexander, Scott

    1992-01-01

    A family of preconditioners for the solution of finite element equations are presented, which are element-topology independent and thus can be applicable to element order-free parallel computations. A key feature of the present preconditioners is the repeated use of element connectivity matrices and their left and right inverses. The properties and performance of the present preconditioners are demonstrated via beam and two-dimensional finite element matrices for implicit time integration computations.

  13. Component Repair Times Obtained from MSPI Data

    International Nuclear Information System (INIS)

    Eide, Steven A.; Cadwallader, Lee

    2015-01-01

    Information concerning times to repair or restore equipment to service given a failure is valuable to probabilistic risk assessments (PRAs). Examples of such uses in modern PRAs include estimation of the probability of failing to restore a failed component within a specified time period (typically tied to recovering a mitigating system before core damage occurs at nuclear power plants) and the determination of mission times for support system initiating event (SSIE) fault tree models. Information on equipment repair or restoration times applicable to PRA modeling is limited and dated for U.S. commercial nuclear power plants. However, the Mitigating Systems Performance Index (MSPI) program covering all U.S. commercial nuclear power plants provides up-to-date information on restoration times for a limited set of component types. This paper describes the MSPI program data available and analyzes the data to obtain median and mean component restoration times as well as non-restoration cumulative probability curves. The MSPI program provides guidance for monitoring both planned and unplanned outages of trains of selected mitigating systems deemed important to safety. For systems included within the MSPI program, plants monitor both train UA and component unreliability (UR) against baseline values. If the combined system UA and UR increases sufficiently above established baseline results (converted to an estimated change in core damage frequency or CDF), a ''white'' (or worse) indicator is generated for that system. That in turn results in increased oversight by the US Nuclear Regulatory Commission (NRC) and can impact a plant's insurance rating. Therefore, there is pressure to return MSPI program components to service as soon as possible after a failure occurs. Three sets of unplanned outages might be used to determine the component repair durations desired in this article: all unplanned outages for the train type that includes the component of

  14. Component Repair Times Obtained from MSPI Data

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Steven A. [Curtiss-Wright/Scietech, Ketchum, ID (United States); Cadwallader, Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    Information concerning times to repair or restore equipment to service given a failure is valuable to probabilistic risk assessments (PRAs). Examples of such uses in modern PRAs include estimation of the probability of failing to restore a failed component within a specified time period (typically tied to recovering a mitigating system before core damage occurs at nuclear power plants) and the determination of mission times for support system initiating event (SSIE) fault tree models. Information on equipment repair or restoration times applicable to PRA modeling is limited and dated for U.S. commercial nuclear power plants. However, the Mitigating Systems Performance Index (MSPI) program covering all U.S. commercial nuclear power plants provides up-to-date information on restoration times for a limited set of component types. This paper describes the MSPI program data available and analyzes the data to obtain median and mean component restoration times as well as non-restoration cumulative probability curves. The MSPI program provides guidance for monitoring both planned and unplanned outages of trains of selected mitigating systems deemed important to safety. For systems included within the MSPI program, plants monitor both train UA and component unreliability (UR) against baseline values. If the combined system UA and UR increases sufficiently above established baseline results (converted to an estimated change in core damage frequency or CDF), a “white” (or worse) indicator is generated for that system. That in turn results in increased oversight by the US Nuclear Regulatory Commission (NRC) and can impact a plant’s insurance rating. Therefore, there is pressure to return MSPI program components to service as soon as possible after a failure occurs. Three sets of unplanned outages might be used to determine the component repair durations desired in this article: all unplanned outages for the train type that includes the component of interest, only

  15. Overview of galactic results obtained by MAGIC

    Energy Technology Data Exchange (ETDEWEB)

    Zanin, Roberta

    2013-06-15

    MAGIC is a system of two atmospheric Cherenkov telescopes which explores the very-high-energy sky, from some tens of GeV up to tens of TeV. Located in the Canary island of La Palma, MAGIC has the lowest energy threshold among the instruments of its kind, well suited to study the still poorly explored energy band below 100 GeV. Although the space-borne gamma-ray telescope Fermi/LAT is sensitive up to 300 GeV, gamma-ray rates drop fast with increasing energy, so γ-ray collection areas larger than 10{sup 4}m{sup 2}, as those provided by grounds-based instruments, are crucial above a few GeV. The combination of MAGIC and Fermi/LAT observations have provided the first astrophysical spectra sampled in the inverse Compton peak region, resulting in a complete coverage from MeV up to TeV energies, as well as the discovery of a pulsed emission in the very-high-energy band. This paper focuses on the latest results on Galactic sources obtained by MAGIC which are highlighted by the detection of the pulsed gamma-ray emission from the Crab pulsar up to 400 GeV. In addition, we will present the morphological study on the W51 complex which allowed to pinpoint the location of the majority of the emission around the interaction point between the supernova remnant W51C and the star forming region W51B, but also to find a possible contribution from the associated pulsar wind nebula. Other important scientific achievements involve the Crab Nebula with an unprecedented spectrum covering three decades in energy starting from 50 GeV and a morphological study of the unidentified source HESS J1857+026 which supports the pulsar wind nebula scenario. Finally we will report on the searches of very-high-energy signals from gamma-ray binaries, mainly LS I 303+ and HESS J0632+057.

  16. Mean Orbital Elements for Geosynchronous Orbit - II - Orbital inclination, longitude of ascending node, mean longitude

    Directory of Open Access Journals (Sweden)

    Kyu-Hong Choi

    1990-06-01

    Full Text Available The osculating orbital elements include the mean, secular, long period, and short period terms. The iterative algorithm used for conversion of osculating orbital elements to mean orbital elements is described. The mean orbital elements of Wc, Ws, and L are obtained.

  17. Transuranium elements in organic chemical forms

    International Nuclear Information System (INIS)

    Sakanoue, Masanobu; Yamamoto, Masayoshi

    1987-01-01

    It is very important to achive an understanding what role organic matter plays in the behavior of transuranium elements in the environment. This paper reports the studies on characteristics of fallout Pu and Am in soil closely related to soil organic matter, and interaction of humic acid and Am (III) in aqueous solution. From the results obtained, it was suggested that the humic acids had strong interaction with transuranium elements, but such soluble complexes were removed soon from the solution by coagulation and sorption on soil. (author)

  18. Saha's ionization equation for high Z elements

    International Nuclear Information System (INIS)

    Godwal, B.K.; Sikka, S.K.

    1977-01-01

    Saha's ionization equation has been solved for high Z elements with the aim of providing input for opacity calculations. Results are presented for two elements, tungsten and uranium. The ionization potentials have been evaluated using the simple Bhor's formula with suitable effective charges for ions. The reliability of the free electron density, ion concentrations, etc., obtained from the Saha's equation solutions has been checked by comparing the P and E computed from them with those given by the Thomas-Fermi-Dirac equation of state. The agreement between the two is good from temperatures above 0.2 keV. (author)

  19. Crack Propagation by Finite Element Method

    Directory of Open Access Journals (Sweden)

    Luiz Carlos H. Ricardo

    2018-01-01

    Full Text Available Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth. Today structural and materials engineers develop structures and materials properties using this technique. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FDandE SAE Keyhole Specimen Test Load Histories by finite element analysis. To understand the crack propagation processes under variable amplitude loading, retardation effects are observed

  20. Archaeal extrachromosomal genetic elements

    DEFF Research Database (Denmark)

    Wang, Haina; Peng, Nan; Shah, Shiraz Ali

    2015-01-01

    SUMMARY: Research on archaeal extrachromosomal genetic elements (ECEs) has progressed rapidly in the past decade. To date, over 60 archaeal viruses and 60 plasmids have been isolated. These archaeal viruses exhibit an exceptional diversity in morphology, with a wide array of shapes, such as spind......SUMMARY: Research on archaeal extrachromosomal genetic elements (ECEs) has progressed rapidly in the past decade. To date, over 60 archaeal viruses and 60 plasmids have been isolated. These archaeal viruses exhibit an exceptional diversity in morphology, with a wide array of shapes...... on archaeal ECEs has just started to unravel the molecular biology of these genetic entities and their interactions with archaeal hosts, it is expected to accelerate in the next decade....

  1. Nuclear fuel element

    Energy Technology Data Exchange (ETDEWEB)

    Armijo, J S; Coffing, L F

    1979-04-05

    The fuel element with circular cross-section for BWR and PWR consists of a core surrounded by a compound jacket container where there is a gap between the core and jacket during operation in the reactor. The core consists of U, Pu, Th compounds and mixtures of these. The compound jacket consists of zircaloy 2 or 4. In order to for example prevent the corrosion of the compound jacket, its inner surface has a metal barrier with smaller neutron absorbers than the jacket material in the form of a zirconium sponge. The zirconium of this metal barrier has impurities of various elements in the order of magnitude of 1000 to 5000 ppm. The oxygen content is in the range of 200 to 1200 ppm and the thickness of the metal barrier is 1-30% of the thickness of the jacket.

  2. Nuclear reactor fuel element

    International Nuclear Information System (INIS)

    D'Eye, R.W.M.; Shennan, J.V.; Ford, L.H.

    1977-01-01

    Fuel element with particles from ceramic fissionable material (e.g. uranium carbide), each one being coated with pyrolitically deposited carbon and all of them being connected at their points of contact by means of an individual crossbar. The crossbar consists of silicon carbide produced by reaction of silicon metal powder with the carbon under the influence of heat. Previously the silicon metal powder together with the particles was kneaded in a solvent and a binder (e.g. epoxy resin in methyl ethyl ketone plus setting agent) to from a pulp. The reaction temperature lies at 1750 0 C. The reaction itself may take place in a nitrogen atmosphere. There will be produced a fuel element with a high overall thermal conductivity. (DG) [de

  3. Nuclear fuel element

    International Nuclear Information System (INIS)

    1974-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed. A heat conducting fission product retaining metal liner of a refractory metal is incorporated in the fuel element between the cladding and the nuclear fuel to inhibit mechanical interaction between the nuclear fuel and the cladding, to isolate fission products and nuclear fuel impurities from contacting the cladding, and to improve the axial thermal peaking gradient along the length of the fuel rod. The metal liner can be in the form of a tube or hollow cylindrical column, a foil of single or multiple layers in the shape of a hollow cylindrical column, or a coating on the internal surface of the cladding. Preferred refractory metal materials are molybdenum, tungsten, rhenium, niobium and alloys of the foregoing metals

  4. Nuclear fuel element

    International Nuclear Information System (INIS)

    Thompson, J.R.; Rowland, T.C.

    1976-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed. A heat conducting, fission product retaining metal liner of a refractory metal is incorporated in the fuel element between the cladding and the nuclear fuel to inhibit mechanical interaction between the nuclear fuel and the cladding, to isolate fission products and nuclear fuel impurities from contacting the cladding and to improve the axial thermal peaking gradient along the length of the fuel rod. The metal liner can be in the form of a tube or hollow cylindrical column, a foil of single or multiple layers in the shape of a hollow cylindrical column, or a coating on the internal surface of the cladding. Preferred refractory metal materials are molybdenum, tungsten, rhenium, niobium and alloys of the foregoing metals

  5. Elements of quantum optics

    CERN Document Server

    Meystre, Pierre

    2007-01-01

    Elements of Quantum Optics gives a self-contained and broad coverage of the basic elements necessary to understand and carry out research in laser physics and quantum optics, including a review of basic quantum mechanics and pedagogical introductions to system-reservoir interactions and to second quantization. The text reveals the close connection between many seemingly unrelated topics, such as probe absorption, four-wave mixing, optical instabilities, resonance fluorescence and squeezing. It also comprises discussions of cavity quantum electrodynamics and atom optics. The 4th edition includes a new chapter on quantum entanglement and quantum information, as well as added discussions of the quantum beam splitter, electromagnetically induced transparency, slow light, and the input-output formalism needed to understand many problems in quantum optics. It also provides an expanded treatment of the minimum-coupling Hamiltonian and a simple derivation of the Gross-Pitaevskii equation, an important gateway to rese...

  6. Periodic table of elements

    International Nuclear Information System (INIS)

    Fluck, E.; Heumann, K.G.

    1985-01-01

    Following a recommendation by the International Union for Pure and Applied Chemistry (IUPAC), the groups of the periodic table shall be numbered from 1 to 18, instead of I to VIII as before. The recommendations has been approved of by the Committee on Nomenclature of the American Chemical Society. The new system abandons the distinction between main groups (a) and auxiliary groups (b), which in the past frequently has been the reason for misunderstandings between European and American chemists, due to different handling. The publishing house VCH Verlagsgesellschaft recently produced a new periodic table that shows the old and the new numbering system together at a glance, so that chemists will have time to get familiar with the new system. In addition the new periodic table represents an extensive data compilation arranged by elements. The front page lists the chemical properties of elements, the back page their physical properties. (orig./EF) [de

  7. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Kawada, Toshiyuki; Hirayama, Satoshi; Yoneya, Katsutoshi.

    1980-01-01

    Purpose: To enable load-depending operation as well as moderation for the restriction of operation conditions in the present nuclear reactors, by specifying the essential ingredients and the total weight of the additives to UO 2 fuel substances. Constitution: Two or more additives selected from Al 2 O 3 , B 2 O, CaO, MgO, SiO 2 , Na 2 O and P 2 O 5 are added by the total weight of 2 - 5% to fuel substances consisting of UO 2 or a mixture of UO 2 and PuO 2 . When the mixture is sintered, the strength of the fuel elements is decreased and the fuel-cladding interactions due to the difference in the heat expansion coefficients between the ceramic fuel elements and the metal claddings are decreased to a substantially harmless degree. (Horiuchi, T.)

  8. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Nakai, Keiichi

    1983-01-01

    Purpose: To decrease the tensile stresses resulted in a fuel can as well as prevent decladding of fuel pellets into the bore holes by decreasing the inner pressure within the nuclear fuel element. Constitution: A fuel can is filled with hollow fuel pellets, inserted with a spring for retaining the hollow fuel pellets with an appropriate force and, thereafter, closely sealed at the both ends with end plugs. A cylindrical body is disposed into the bore holes of the hollow fuel pellets. Since initial sealing gases and/or gaseous nuclear fission products can thus be excluded from the bore holes where the temperature is at the highest level, the inner pressure of the nuclear fuel element can be reduced to decrease the tensile strength resulted to the fuel can. Furthermore, decladding of fuel pellets into the bore holes can be prevented. (Moriyama, K.)

  9. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Ainsworth, K.F.

    1979-01-01

    A nuclear fuel element is described having a cluster of nuclear fuel pins supported in parallel, spaced apart relationship by transverse cellular braces within coaxial, inner and outer sleeves, the inner sleeve being in at least two separate axial lengths, each of the transverse braces having a peripheral portion which is clamped peripherally between the ends of the axial lengths of the inner sleeve. (author)

  10. Sensor for ionizable elements

    International Nuclear Information System (INIS)

    Berkey, E.; Reed, W.A. III; Hickam, W.M.

    1977-01-01

    Sensor to detect thermally ionizable elements or molucules in air, water vapour or oxygen or to be used as alkali leak detector in vacuum systems, e.g. in the pipe system of a liquid-metal cooled FBR. The sensor consists of an filament made of thorium-containing iridium as cathode with a temperature upto 1000 0 C and an anode sheet of molybdenum, nickel or stainless steal. (ORU) [de

  11. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Butterfield, C.E.; Waite, E.

    1982-01-01

    A nuclear reactor fuel element comprising a column of vibration compacted fuel which is retained in consolidated condition by a thimble shaped plug. The plug is wedged into gripping engagement with the wall of the sheath by a wedge. The wedge material has a lower coefficient of expansion than the sheath material so that at reactor operating temperature the retainer can relax sufficient to accommodate thermal expansion of the column of fuel. (author)

  12. OXIDATION OF TRANSURANIC ELEMENTS

    Science.gov (United States)

    Moore, R.L.

    1959-02-17

    A method is reported for oxidizing neptunium or plutonium in the presence of cerous values without also oxidizing the cerous values. The method consists in treating an aqueous 1N nitric acid solution, containing such cerous values together with the trivalent transuranic elements, with a quantity of hydrogen peroxide stoichiometrically sufficient to oxidize the transuranic values to the hexavalent state, and digesting the solution at room temperature.

  13. Transportation of radioactive elements

    International Nuclear Information System (INIS)

    Thubert, Francis; Rentien, Guy; Jacquet, Michel

    1981-01-01

    The production and marketing of artificial radioactive elements engaged in by the 'Office des Rayonnements Ionisants' requires the use of specially designed packagings and assorted means of transport. The authors begin by describing the different kinds of products involved and the forms of packagings needed, and go on to discuss the various means of transport used, underlining the fact that, in terms of number and gravity, the incidents that have occurred to date have indeed been few and far between [fr

  14. Vented nuclear fuel element

    International Nuclear Information System (INIS)

    Oguma, M.; Hirose, Y.

    1976-01-01

    A description is given of a vented nuclear fuel element having a plenum for accumulation of fission product gases and plug means for delaying the release of the fission product gases from the plenum, the plug means comprising a first porous body wettable with a liquid metal and a second porous body non-wettable with the liquid metal, the first porous body being impregnated with the liquid metal and in contact with the liquid metal

  15. Helium the disappearing element

    CERN Document Server

    Sears, Wheeler M

    2015-01-01

    The subject of the book is helium, the element, and its use in myriad applications including MRI machines, particle accelerators, space telescopes, and of course balloons and blimps. It was at the birth of our Universe, or the Big Bang, where the majority of cosmic helium was created; and stellar helium production continues. Although helium is the second most abundant element in the Universe, it is actually quite rare here on Earth and only exists because of radioactive elements deep within the Earth. This book includes a detailed history of the discovery of helium, of the commercial industry built around it, how the helium we actually encounter is produced within the Earth, and the state of the helium industry today. The gas that most people associate with birthday party balloons is running out. “Who cares?” you might ask. Well, without helium, MRI machines could not function, rockets could not go into space, particle accelerators such as those used by CERN could not operate, fiber optic cables would not...

  16. Elements of quantum information

    International Nuclear Information System (INIS)

    Schleich, W.P.

    2007-01-01

    Elements of Quantum Information introduces the reader to the fascinating field of quantum information processing, which lives on the interface between computer science, physics, mathematics, and engineering. This interdisciplinary branch of science thrives on the use of quantum mechanics as a resource for high potential modern applications. With its wide coverage of experiments, applications, and specialized topics - all written by renowned experts - Elements of Quantum Information provides and indispensable, up-to-date account of the state of the art of this rapidly advancing field and takes the reader straight up to the frontiers of current research. The articles have first appeared as a special issue of the journal 'Fortschritte der Physik / Progress of Physics'. Since then, they have been carefully updated. The book will be an inspiring source of information and insight for anyone researching and specializing in experiments and theory of quantum information. Topics addressed in Elements of Quantum Information include - Cavity Quantum Electrodynamics - Segmented Paul Traps - Cold Atoms and Bose-Einstein Condensates in Microtraps, Optical Lattices, and on Atom Chips - Rydberg Gases - Factorization of Numbers with Physical Systems - Entanglement of Continuous Variables - NMR and Solid State Quantum Computation - Quantum Algorithms and Quantum Machines - Complexity Theory - Quantum Crytography. (orig.)

  17. Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    M.H.R. Ghoreishy

    2008-02-01

    Full Text Available This research work is devoted to the footprint analysis of a steel-belted radial tyre (185/65R14 under vertical static load using finite element method. Two models have been developed in which in the first model the tread patterns were replaced by simple ribs while the second model was consisted of details of the tread blocks. Linear elastic and hyper elastic (Arruda-Boyce material models were selected to describe the mechanical behavior of the reinforcing and rubbery parts, respectively. The above two finite element models of the tyre were analyzed under inflation pressure and vertical static loads. The second model (with detailed tread patterns was analyzed with and without friction effect between tread and contact surfaces. In every stage of the analysis, the results were compared with the experimental data to confirm the accuracy and applicability of the model. Results showed that neglecting the tread pattern design not only reduces the computational cost and effort but also the differences between computed deformations do not show significant changes. However, more complicated variables such as shape and area of the footprint zone and contact pressure are affected considerably by the finite element model selected for the tread blocks. In addition, inclusion of friction even in static state changes these variables significantly.

  18. Study of Superheavy Elements

    International Nuclear Information System (INIS)

    Hofmann, Sigurd

    2007-01-01

    The nuclear shell model predicts that the next doubly magic shell-closure beyond 208 Pb is at a proton number Z = 114, 120, or 126 and at a neutron number N = 172 or 184. The outstanding aim of experimental investigations is the exploration of this region of spherical 'SuperHeavy Elements' (SHEs). Experimental methods are described, which allowed for the identification of elements produced on a cross-section level of about 1 pb. The decay data reveal that for the heaviest elements, the dominant decay mode is alpha emission, not fission. Decay properties as well as reaction cross-sections are compared with results of theoretical investigations. Finally, plans are presented for the further development of the experimental set-up and the application of new techniques, as for instance the precise mass measurement of the produced nuclei using ion traps. At increased sensitivity, the detailed exploration of the region of spherical SHEs will start, after first steps on the island were made in recent years. (Author)

  19. Probabilistic finite elements

    Science.gov (United States)

    Belytschko, Ted; Wing, Kam Liu

    1987-01-01

    In the Probabilistic Finite Element Method (PFEM), finite element methods have been efficiently combined with second-order perturbation techniques to provide an effective method for informing the designer of the range of response which is likely in a given problem. The designer must provide as input the statistical character of the input variables, such as yield strength, load magnitude, and Young's modulus, by specifying their mean values and their variances. The output then consists of the mean response and the variance in the response. Thus the designer is given a much broader picture of the predicted performance than with simply a single response curve. These methods are applicable to a wide class of problems, provided that the scale of randomness is not too large and the probabilistic density functions possess decaying tails. By incorporating the computational techniques we have developed in the past 3 years for efficiency, the probabilistic finite element methods are capable of handling large systems with many sources of uncertainties. Sample results for an elastic-plastic ten-bar structure and an elastic-plastic plane continuum with a circular hole subject to cyclic loadings with the yield stress on the random field are given.

  20. Multi-elemental characterization of Cuban natural zeolites

    International Nuclear Information System (INIS)

    Rizo, O.D.; Peraza, E.F.H.

    1997-01-01

    Concentration of 38 elements in samples from four important Cuban zeolite beds have been obtained by Instrumental Neutron Activation (INAA) and X-ray Fluorescence analyses (XRFA). In comparison with other analytical techniques good agreement was reached. The concentration values of minor element Ba, Sr, Zn and Mn and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses. (author)

  1. Numerical and spectral investigations of novel infinite elements

    International Nuclear Information System (INIS)

    Barai, P.; Harari, I.; Barbonet, P.E.

    1998-01-01

    Exterior problems of time-harmonic acoustics are addressed by a novel infinite element formulation, defined on a bounded computational domain. For two-dimensional configurations with circular interfaces, the infinite element results match Quell both analytical values and those obtained from. other methods like DtN. Along 1uith the numerical performance of this formulation, of considerable interest are its complex-valued eigenvalues. Hence, a spectral analysis of the present scheme is also performed here, using various infinite elements

  2. Toxic and trace elements in foodstuffs in Japan

    International Nuclear Information System (INIS)

    Muramatsu, Y.; Sumiya, M.; Ohmomo, Y.

    1988-01-01

    From the viewpoint of environmental safety assessment it is important to have information on the levels of toxic and trace elements in foodstuffs. It is also essential to develop suitable analytical methods for these elements in order to obtain accurate analytical data. In this paper, two analytical methods were used, inductively-coupled plasma atomic emission spectrometry (ICP-AES) and neutron activation analysis (NAA), for analysing toxic and trace elements in several food samples. 3 tabs

  3. Multi-elemental characterization of Cuban natural zeolites

    International Nuclear Information System (INIS)

    Diaz Rizo, O.; Herrera Peraza, E.F.

    1996-01-01

    Concentrations of 38 elements in samples from four important Cuban zeolite bed have beam obtained by Instrumental Neutron Activation (INAA) and X-Ray Fluorescence Analysis (XRFA). In comparison with other analytical techniques good agreement was achieved. The concentration values of minor element Ba, Sr, Zn, and Mn, and 25 trace element (including 9 REE) are at the first time reported in Cuban zeolite. It is important for the zeolite evaluation in different industrial uses

  4. New functionalities in abundant element oxides: ubiquitous element strategy

    International Nuclear Information System (INIS)

    Hosono, Hideo; Hayashi, Katsuro; Kamiya, Toshio; Atou, Toshiyuki; Susaki, Tomofumi

    2011-01-01

    While most ceramics are composed of ubiquitous elements (the ten most abundant elements within the Earth's crust), many advanced materials are based on rare elements. A 'rare-element crisis' is approaching owing to the imbalance between the limited supply of rare elements and the increasing demand. Therefore, we propose a 'ubiquitous element strategy' for materials research, which aims to apply abundant elements in a variety of innovative applications. Creation of innovative oxide materials and devices based on conventional ceramics is one specific challenge. This review describes the concept of ubiquitous element strategy and gives some highlights of our recent research on the synthesis of electronic, thermionic and structural materials using ubiquitous elements. (topical review)

  5. The transuranium elements: From neptunium and plutonium to element 112

    International Nuclear Information System (INIS)

    Hoffman, D.C.

    1996-01-01

    Beginning in the 1930's, both chemists and physicists became interested in synthesizing new artificial elements. The first transuranium element, Np, was synthesized in 1940. Over the past six decades, 20 transuranium elements have been produced. A review of the synthesis is given. The procedure of naming the heavy elements is also discussed. It appears feasible to produce elements 113 and 114. With the Berkeley Gas-filled Separator, it should be possible to reach the superheavy elements in the region of the spherical Z=114 shell, but with fewer neutrons than the N=184 spherical shell. 57 refs, 6 figs

  6. Two New Quadrilateral Elements Based on Strain States

    Directory of Open Access Journals (Sweden)

    Mohammad Rezaiee-Pajand

    2015-06-01

    Full Text Available In this paper, two new quadrilateral elements are formulated to solve plane problems. Low sensitivity to geometric distortion, no parasitic shear error, rotational invariance, and satisfying the Felippa pure bending test are characteristics of these suggested elements. One proposed element is formulated by establishing equilibrium equations for the second-order strain field. The other suggested element is obtained by establishing equilibrium equations only for the linear part of the strain field. The number of the strain states decreases when the conditions among strain states are satisfied. Several numerical tests are used to demonstrate the performance of the proposed elements. Famous elements, which were suggested by other researchers, are used as a means of comparison. It is shown that these novel elements pass the strong patch tests, even for extremely poor meshes, and one of them has an excellent accuracy and fast convergence in other complicated problems.

  7. A Finite Element Model for convection-dominatel transport problems

    International Nuclear Information System (INIS)

    Carmo, E.G.D. do; Galeao, A.C.N.R.

    1987-08-01

    A new Protev-Galerkin Finite Element Model which automatically incorporates the search for the appropriate upwind direction is presented. It is also shown that modifying the Petrov-Galerkin weightin functions associated with elements adjascent to downwing boudaries effectively eliminates numerical oscillations normally obtained near boundary layers. (Author) [pt

  8. A finite element thermohydrodynamic analyis of profile bore bearing

    International Nuclear Information System (INIS)

    Shah Nor bin Basri

    1994-01-01

    A finite element-based method is presented for analysing the thermohydrodynamic (THD) behaviour of profile bore bearing. A variational statement for the governing equation is derived and used to formulate a non-linear quadrilateral finite element of serendipity family. The predicted behaviour is compared with experimental evidence where possible and favorable correlation is obtained

  9. PROBABILISTIC ESTIMATION OF VIBRATION INFLUENCE ON SENSITIVE SYSTEM ELEMENTS

    Directory of Open Access Journals (Sweden)

    A. A. Lobaty

    2009-01-01

    Full Text Available The paper considers a problem pertaining to an estimation of vibration influence on sensitive system elements. Dependences of intensity and probability of a process exit characterizing a condition of a system element for the preset range that allow to estimate serviceability and no-failure operation of the system have been obtained analytically in the paper

  10. Modelling Convergence of Finite Element Analysis of Cantilever Beam

    African Journals Online (AJOL)

    Convergence studies are carried out by investigating the convergence of numerical results as the number of elements is increased. If convergence is not obtained, the engineer using the finite element method has absolutely no indication whether the results are indicative of a meaningful approximation to the correct solution ...

  11. Rare earth elements materials production from apatite ores

    International Nuclear Information System (INIS)

    Anufrieva, A V; Buynovskiy, A S; Makaseev, Y N; Mazov, I N; Nefedov, R A; Sachkov, V I; Valkov, A V; Andrienko, O S; Stepanova, O B

    2016-01-01

    The paper deals with the study of processing apatite ores with nitric acid and extraction of the rare earth elements. The rare earth elements can be successfully separated and recovered by extraction from the nitrate- phosphate solution, being an tributyl phosphate as extraction agent. The developed scheme of the processing apatite concentrate provides obtaining rare earth concentrates with high qualitative characteristics. (paper)

  12. Platinum-group elements

    Science.gov (United States)

    Zientek, Michael L.; Loferski, Patricia J.; Parks, Heather L.; Schulte, Ruth F.; Seal, Robert R.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    The platinum-group elements (PGEs)—platinum, palladium, rhodium, ruthenium, iridium, and osmium—are metals that have similar physical and chemical properties and tend to occur together in nature. PGEs are indispensable to many industrial applications but are mined in only a few places. The availability and accessibility of PGEs could be disrupted by economic, environmental, political, and social events. The United States net import reliance as a percentage of apparent consumption is about 90 percent.PGEs have many industrial applications. They are used in catalytic converters to reduce carbon monoxide, hydrocarbon, and nitrous oxide emissions in automobile exhaust. The chemical industry requires platinum or platinum-rhodium alloys to manufacture nitric oxide, which is the raw material used to manufacture explosives, fertilizers, and nitric acid. In the petrochemical industry, platinum-supported catalysts are needed to refine crude oil and to produce aromatic compounds and high-octane gasoline. Alloys of PGEs are exceptionally hard and durable, making them the best known coating for industrial crucibles used in the manufacture of chemicals and synthetic materials. PGEs are used by the glass manufacturing industry in the production of fiberglass and flat-panel and liquid crystal displays. In the electronics industry, PGEs are used in computer hard disks, hybridized integrated circuits, and multilayer ceramic capacitors.Aside from their industrial applications, PGEs are used in such other fields as health, consumer goods, and finance. Platinum, for example, is used in medical implants, such as pacemakers, and PGEs are used in cancer-fighting drugs. Platinum alloys are an ideal choice for jewelry because of their white color, strength, and resistance to tarnish. Platinum, palladium, and rhodium in the form of coins and bars are also used as investment commodities, and various financial instruments based on the value of these PGEs are traded on major exchanges

  13. Statistical evaluation of the data obtained from the K East Basin Sandfilter Backwash Pit samples

    International Nuclear Information System (INIS)

    Welsh, T.L.

    1994-01-01

    Samples were obtained from different locations from the K Each Sandfilter Backwash Pit to characterize the sludge material. These samples were analyzed chemically for elements, radionuclides, and residual compounds. The analytical results were statistically analyzed to determine the mean analyte content and the associated variability for each mean value

  14. Inadvertent presence of genetically modified elements in maize food ...

    African Journals Online (AJOL)

    owner

    2013-07-31

    Jul 31, 2013 ... The maize imported into Kenya contained Bt genetic elements. Nevertheless, the .... obtained from various open air markets and retail shops located in ... Magic, Bokomo and Temmy) was not successful. Assessment of cry1Ab ...

  15. Finite element model to study calcium distribution in oocytes ...

    African Journals Online (AJOL)

    Parvaiz Ahmad Naik

    2015-03-20

    Mar 20, 2015 ... Department of Mathematics, Maulana Azad National Institute of Technology, Bhopal 462051 ... finite element method has been employed to obtain the solution. ..... Nelson MT, Cheng H, Rubart M. Relaxation of arterial smooth.

  16. Simple electrolytic cell for production of elemental fluorine

    International Nuclear Information System (INIS)

    Dides F, M.; Padilla S, U.

    1990-01-01

    It was constructed and tested a simple electrolytic cell for the production of elemental fluorine. The fluorine production is essential in the obtainment of uranium hexafluoride, a compound for the nuclear fuel cycle. (A.C.A.S.)

  17. Recovery of trans-plutonium elements; Recuperation des elements transplutoniens

    Energy Technology Data Exchange (ETDEWEB)

    Espie, J Y; Poncet, B; Simon, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1970-07-01

    The object of this work is to study the recovery of americium and curium from the fission-product solution obtained from the processing of irradiated fuel elements made of natural metallic uranium alloyed with aluminium, iron and silicon; these elements have been subjected to an average irradiation of 4000 MW days/ton in a gas-graphite type reactor having a thermal power of 3.7 MW/ton of uranium. The process used consists of 3 extraction cycles and one americium-curium separation: - 1) extraction cycle in 40 per cent TBP: extraction of actinides and lanthanides; elimination of fission products; - 2) extraction cycle in 8 per cent D2EHPA: decontamination from the fission products, decontamination of actinides from lanthanides; - 3) extraction cycle in 40 per cent TBP: separation of the complexing agent and concentration of the actinides; - 4) americium-curium separation by precipitation. (authors) [French] Cette etude a pour objet, la recuperation de l'americium et du curium de la solution de produits de fission provenant du traitement de combustibles irradies a base d'uranium naturel metallique allie a l'aluminium, le fer, et le silicium, et ayant subi une irradiation moyenne de 4000 MWj/t dans une pile du type graphite-gaz, dont la puissance thermique est de 3.7 MW/t d'uranium. Le procede utilise comprend 3 cycles d'extraction et une separation americium-curium: - 1. cycle d'extraction dans le TBP a 40 pour cent: extraction des actinides et des lanthanides, elimination des produits de fission; - 2. cycle d'extraction dans le D2EHPA a 8 pour cent: decontamination en produits de fission, decontamination des actinides en lanthanides; - 3. cycle d'extraction dans le TBP a 40 pour cent: separation du complexant et concentration des actinides; - 4. separation americium-curium par precipitation. (auteurs)

  18. Boundary element method for modelling creep behaviour

    International Nuclear Information System (INIS)

    Zarina Masood; Shah Nor Basri; Abdel Majid Hamouda; Prithvi Raj Arora

    2002-01-01

    A two dimensional initial strain direct boundary element method is proposed to numerically model the creep behaviour. The boundary of the body is discretized into quadratic element and the domain into quadratic quadrilaterals. The variables are also assumed to have a quadratic variation over the elements. The boundary integral equation is solved for each boundary node and assembled into a matrix. This matrix is solved by Gauss elimination with partial pivoting to obtain the variables on the boundary and in the interior. Due to the time-dependent nature of creep, the solution has to be derived over increments of time. Automatic time incrementation technique and backward Euler method for updating the variables are implemented to assure stability and accuracy of results. A flowchart of the solution strategy is also presented. (Author)

  19. Chemical element abundance in K giant atmospheres

    International Nuclear Information System (INIS)

    Komarov, N.S.; Shcherbak, A.N.

    1980-01-01

    With the help of modified method of differential curves of growth studied are physical parameters of atmospheres of giant stars of KO111 spectral class of the NGC 752, M25 and UMa cluster. Observations have been made on reflector of Crimea astrophysical observatory of Academy of Sciences of the USSR in the period from February to May, 1978. Spectograms are obtained for the wave length range from 5000-5500 A. It is shown that the change of chemical content in the wide range in heavy element composition does not influence the star atmosphere structUre. It follows from the results of the investigation that the abundance of chemical elements in stars of various scattered clusters, is the same in the range of errors of measurements and is similar to the abundance of chemical elements in the Sun atmosphere

  20. Fractional Order Element Based Impedance Matching

    KAUST Repository

    Radwan, Ahmed Gomaa

    2014-06-24

    Disclosed are various embodiments of methods and systems related to fractional order element based impedance matching. In one embodiment, a method includes aligning a traditional Smith chart (|.alpha.|=1) with a fractional order Smith chart (|.alpha.|.noteq.1). A load impedance is located on the traditional Smith chart and projected onto the fractional order Smith chart. A fractional order matching element is determined by transitioning along a matching circle of the fractional order Smith chart based at least in part upon characteristic line impedance. In another embodiment, a system includes a fractional order impedance matching application executed in a computing device. The fractional order impedance matching application includes logic that obtains a first set of Smith chart coordinates at a first order, determines a second set of Smith chart coordinates at a second order, and determines a fractional order matching element from the second set of Smith chart coordinates.

  1. ZONE: a finite element mesh generator

    International Nuclear Information System (INIS)

    Burger, M.J.

    1976-05-01

    The ZONE computer program is a finite-element mesh generator which produces the nodes and element description of any two-dimensional geometry. The geometry is subdivided into a mesh of quadrilateral and triangular zones arranged sequentially in an ordered march through the geometry. The order of march can be chosen so that the minimum bandwidth is obtained. The node points are defined in terms of the x and y coordinates in a global rectangular coordinate system. The zones generated are quadrilaterals or triangles defined by four node points in a counterclockwise sequence. Node points defining the outside boundary are generated to describe pressure boundary conditions. The mesh that is generated can be used as input to any two-dimensional as well as any axisymmetrical structure program. The output from ZONE is essentially the input file to NAOS, HONDO, and other axisymmetric finite element programs. 14 figures

  2. Dynamic characterization of the CAREM fuel element prototype

    International Nuclear Information System (INIS)

    Ghiselli, Alberto M.; Fiori, Jose M.; Ibanez, Luis A.

    2004-01-01

    As a previous step to make a complete test plan to evaluate the hydrodynamic behavior of the present configuration of the CAREM type fuel element, a dynamic characterization analysis is required, without the dynamic response induced by the flowing fluid. This paper presents the tests made, the methods and instrumentation used, and the results obtained in order to obtain a complete dynamic characterization of the CAREM type fuel element. (author)

  3. Elements of social action

    Directory of Open Access Journals (Sweden)

    Marjanović Miloš

    2011-01-01

    Full Text Available Because of the significant analytical advantages, the author prefers social action as initial sociological concept in the relation to social phenomenon. Its basic elements are: actors, subjects and tools, needs and interests, values and norms, positions and roles. Actors set in motion and unify the rest of elements, guide to the magic triangle of sociology (movement, change, order, reaffirm actor paradigm to systemic paradigm. Subjects and tools materialize an action and its overestimate results in technological determinism or (by means of property as institutional appropriation of nature in the (unclassed historical type of society. Needs and interests are the basis of person's motivation and starting point for depth analysis of sociability. The expansion of legitimate interests circle develops techniques of normative regulation. Values and norms guide to institutional-organizational, positions to vertical and roles to horizontal structure. Values give the meaning to the action as well as to human existence, they are orientations of motivate system of personality but also basic aspect of society. As abstractions, values are latent background of norms and they tell to us what to do, and norms how to do something. Norms are specified instructions for suitable behavior Without normative order, not to be possible the satisfying of needs and the conciliation of interests. Riches, power and prestige are components of social position, and legal status is the determination of rights and obligations of the position. Roles are normative expectation of behavior. Toward kinds of sanctions roles are classified. Roles but also other elements of social action are starting point for sociological analysis of legal norms and institutes. On the other side, the observation of legal component of social actions enriches, strengths and precises sociological analysis of them.

  4. Analytical elements of mechanics

    CERN Document Server

    Kane, Thomas R

    2013-01-01

    Analytical Elements of Mechanics, Volume 1, is the first of two volumes intended for use in courses in classical mechanics. The books aim to provide students and teachers with a text consistent in content and format with the author's ideas regarding the subject matter and teaching of mechanics, and to disseminate these ideas. The book opens with a detailed exposition of vector algebra, and no prior knowledge of this subject is required. This is followed by a chapter on the topic of mass centers, which is presented as a logical extension of concepts introduced in connection with centroids. A

  5. Improved nuclear fuel element

    International Nuclear Information System (INIS)

    Klepfer, H.H.

    1974-01-01

    A nuclear fuel element is described which comprises: 1) an elongated clad container, 2) a layer of high lubricity material being disposed in and adjacent to the clad container, 3) a low neutron capture cross section metal liner being disposed in the clad container and adjacent to the layer, 4) a central core of a body of nuclear fuel material disposed in and partially filling the container and forming an internal cavity in the container, 5) an enclosure integrally secured and sealed at each end of the container, and a nuclear fuel material retaining means positioned in the cavity. (author)

  6. Elements of real analysis

    CERN Document Server

    Sprecher, David A

    2010-01-01

    This classic text in introductory analysis delineates and explores the intermediate steps between the basics of calculus and the ultimate stage of mathematics: abstraction and generalization.Since many abstractions and generalizations originate with the real line, the author has made it the unifying theme of the text, constructing the real number system from the point of view of a Cauchy sequence (a step which Dr. Sprecher feels is essential to learn what the real number system is).The material covered in Elements of Real Analysis should be accessible to those who have completed a course in

  7. Nuclear reactor fuel elements

    International Nuclear Information System (INIS)

    Hindle, E. D.

    1984-01-01

    An array of rods is assembled to form a fuel element for a pressurized water reactor, the rods comprising zirconium alloy sheathed nuclear fuel pellets and containing helium. The helium gas pressure is selected for each rod so that it differs substantially from the helium gas pressure in its closest neighbors. In a preferred arrangement the rods are arranged in a square lattice and the helium gas pressure alternates between a relatively high value and a relatively low value so that each rod has as its closest neighbors up to four rods containing helium gas at the other pressure value

  8. Nuclear reactor fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, E. D.

    1984-10-16

    An array of rods is assembled to form a fuel element for a pressurized water reactor, the rods comprising zirconium alloy sheathed nuclear fuel pellets and containing helium. The helium gas pressure is selected for each rod so that it differs substantially from the helium gas pressure in its closest neighbors. In a preferred arrangement the rods are arranged in a square lattice and the helium gas pressure alternates between a relatively high value and a relatively low value so that each rod has as its closest neighbors up to four rods containing helium gas at the other pressure value.

  9. Osteoporosis and trace elements

    DEFF Research Database (Denmark)

    Aaseth, J.; Boivin, G.; Andersen, Ole

    2012-01-01

    More than 200 million people are affected by osteoporosis worldwide, as estimated by 2 million annual hip fractures and other debilitating bone fractures (vertebrae compression and Colles' fractures). Osteoporosis is a multi-factorial disease with potential contributions from genetic, endocrine...... in new bone and results in a net gain in bone mass, but may be associated with a tissue of poor quality. Aluminum induces impairment of bone formation. Gallium and cadmium suppresses bone turnover. However, exact involvements of the trace elements in osteoporosis have not yet been fully clarified...

  10. [Healthcare marketing elements].

    Science.gov (United States)

    Ameri, Cinzia; Fiorini, Fulvio

    2014-01-01

    Marketing puts its foundation on a few key concepts: need-demand, product-service, satisfaction, exchange, market, or business structure manufacturing / supply. The combination of these elements allows you to build an effective marketing strategy. Crucial in this respect is to remember the Porter matrix, which shows that for a correct analysis of the relevant market is necessary to refer to the "five forces at play", ie: customers, competitors, new entrants and substitutes threat. Another key lever for proper marketing oriented approach is the continuous and constant monitoring of the application, anticipating their dissatisfactions.

  11. Technical Elements (CCT1)

    DEFF Research Database (Denmark)

    Thomsen, Kirsten Engelund; Wittchen, Kim Bjarne

    2017-01-01

    Many of the aspects dealt with in the CA EPBD are closely interlinked with each other and may refer to both new and existing buildings, as well as to inspection and certification. This is also true for technical aspects, such as the calculation methodologies, and how to include technical systems......’ efficiency or how to integrate renewable energy within them. The central team for Technical Elements deals with issues of a technical nature, which are common to new and existing buildings, and/or with minimum demands, certification and inspection. This report focuses on the implementation of Articles 3, 4...

  12. Optical Finite Element Processor

    Science.gov (United States)

    Casasent, David; Taylor, Bradley K.

    1986-01-01

    A new high-accuracy optical linear algebra processor (OLAP) with many advantageous features is described. It achieves floating point accuracy, handles bipolar data by sign-magnitude representation, performs LU decomposition using only one channel, easily partitions and considers data flow. A new application (finite element (FE) structural analysis) for OLAPs is introduced and the results of a case study presented. Error sources in encoded OLAPs are addressed for the first time. Their modeling and simulation are discussed and quantitative data are presented. Dominant error sources and the effects of composite error sources are analyzed.

  13. Elements of energy conversion

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Elements of Energy Conversion brings together scattered information on the subject of energy conversion and presents it in terms of the fundamental thermodynamics that apply to energy conversion by any process. Emphasis is given to the development of the theory of heat engines because these are and will remain most important power sources. Descriptive material is then presented to provide elementary information on all important energy conversion devices. The book contains 10 chapters and opens with a discussion of forms of energy, energy sources and storage, and energy conversion. This is foll

  14. Nuclear fuel element

    International Nuclear Information System (INIS)

    Iwano, Yoshihiko.

    1993-01-01

    Microfine cracks having a depth of less than 10% of a pipe thickness are disposed radially from a central axis each at an interval of less than 100 micron over the entire inner circumferential surface of a zirconium alloy fuel cladding tube. For manufacturing such a nuclear fuel element, the inside of the cladding tube is at first filled with an electrolyte solution of potassium chloride. Then, electrolysis is conducted using the cladding tube as an anode and the electrolyte solution as a cathode, and the inner surface of the cladding tube with a zirconium dioxide layer having a predetermined thickness. Subsequently, the cladding tube is laid on a smooth steel plate and lightly compressed by other smooth steel plate to form microfine cracks in the zirconium dioxide layer on the inner surface of the cladding tube. Such a compressing operation is continuously applied to the cladding tube while rotating the cladding tube. This can inhibit progress of cracks on the inner surface of the cladding tube, thereby enabling to prevent failure of the cladding tube even if a pellet/cladding tube mechanical interaction is applied. Accordingly, reliability of the nuclear fuel elements is improved. (I.N.)

  15. Heavy-element nucleosynthesis

    International Nuclear Information System (INIS)

    Mathews, G.J.

    1990-01-01

    New measurements and theoretical studies of nuclear properties, together with new astronomical data on the growth of heavy-element abundances during the early history of the Galaxy, now provide a clearer picture of where in nature the elements heavier than iron are produced by rapid (r-process) and show (s-process) neutron capture reactions. The nuclear data suggest that the r-process involves a high-neutron-density beta-flow equilibrium environment and that the s-process may have occurred at a temperature and neutron density consistent with a 13 C(α,n) 16 0 neutron source. The astronomical data, when compared with simple galactic chemical evolution modes, suggests that the r-process is associated with type II supernovae and that the neutron source must be manufactured by the star. Low-mass type II supernovae are proposed as the most important contributors to the r-process. A 13 C neutron source in intermediate-mass stars is proposed for the s-process. 64 refs., 7 figs

  16. Improved nuclear fuel element

    International Nuclear Information System (INIS)

    1980-01-01

    The invention is of a nuclear fuel element which comprises a central core of a body of nuclear fuel material selected from the group consisting of compounds of uranium, plutonium, thorium and mixtures thereof, and an elongated composite cladding container comprising a zirconium alloy tube containing constituents other than zirconium in an amount greater than about 5000 parts per million by weight and an undeformed metal barrier of moderate purity zirconium bonded to the inside surface of the alloy tube. The container encloses the core so as to leave a gap between the container and the core during use in a nuclear reactor. The metal barrier is of moderate purity zirconium with an impurity level on a weight basis of at least 1000ppm and less than 5000ppm. Impurity levels of specific elements are given. Variations of the invention are also specified. The composite cladding reduces chemical interaction, minimizes localized stress and strain corrosion and reduces the likelihood of a splitting failure in the zirconium alloy tube. Other benefits are claimed. (U.K.)

  17. Stress and Deformation Analysis in Base Isolation Elements Using the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Claudiu Iavornic

    2011-01-01

    Full Text Available In Modern tools as Finite Element Method can be used to study the behavior of elastomeric isolation systems. The simulation results obtained in this way provide a large series of data about the behavior of elastomeric isolation bearings under different types of loads and help in taking right decisions regarding geometrical optimizations needed for improve such kind of devices.

  18. Diversity of staphylococcal cassette chromosome mec structures in coagulase-negative staphylococci and relationship to drug resistance.

    Science.gov (United States)

    Garza-González, Elvira; López, Daniel; Pezina, Cesar; Muruet, Walter; Bocanegra-García, Virgilio; Muñoz, Ivan; Ramírez, Camilo; Llaca-Díaz, Jorge M

    2010-03-01

    The objective of this study was to determine the distribution of staphylococcal cassette chromosome mec (SCCmec) elements in meticillin-resistant coagulase-negative staphylococci (MR-CoNS) isolated from a tertiary-care hospital in Mexico and to examine the relationship to drug resistance. Fifty selected MR-CoNS isolates collected from catheters (n=15), blood (n=15), bone (n=9), bronchial lavage (n=2) and urine (n=2) and one isolate each from an abscess, cerebrospinal fluid, eye, pleural effusion, synovial fluid, tracheal aspirate and wound secretion were examined. Susceptibility testing was performed by the broth microdilution method. SCCmec types were determined by multiplex PCR and PFGE was carried out as described previously for Staphylococcus aureus. Among the MR-CoNS strains studied, the most frequently isolated species were Staphylococcus epidermidis (n=26) and Staphylococcus haemolyticus (n=13). Staphylococcus cohnii (n=5), Staphylococcus hominis (n=3), Staphylococcus sciuri (n=1), Staphylococcus pasteuri (n=1) and the recently described species Staphylococcus pettenkoferi (n=1) were also identified. The most frequent MR-CoNS genotype identified was SCCmec type IVa in S. epidermidis isolates, which also showed a high diversity in their PFGE patterns. A clone was found that amplified both SCCmec III and V elements in five isolates examined. The single MR S. pettenkoferi isolate harboured SCCmec type IVd and the single MR S. pasteuri isolate harboured SCCmec type I. The carriage of SCCmec type III was associated with resistance or intermediate resistance to meropenem (P <0.05). These results confirm the high prevalence of S. epidermidis SCCmec IVa and the high genetic diversity among MR-CoNS strains. As far as is known, this is the first report describing the newly identified S. pettenkoferi possessing SCCmec IVd and S. pasteuri harbouring SCCmec type I. MR-CoNS harbouring SCCmec type III were found to be more resistant to meropenem.

  19. NIH Common Data Elements Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — The NIH Common Data Elements (CDE) Repository has been designed to provide access to structured human and machine-readable definitions of data elements that have...

  20. Neutron-activation analysis of trace elements in thyroids

    International Nuclear Information System (INIS)

    Boulyga, S.F.; Petri, H.; Kanash, N.V.; Malenchenko, A.F.

    1999-01-01

    Neutron activation analysis was used for routine measurement of trace elements in thyroids of inhabitants of Belarus as well as in thyroids of people operated for thyroid cancer. The method chosen allowed the analysis of 28 elements, among them essential and toxic ones, with a good accuracy. The results obtained showed significant differences in the elemental composition of thyroid from the different regions. The changes of elemental composition of thyroids of inhabitants of the Gomel region, where goiter is endemic, seem to be identical to those in the tumor tissue. (author)

  1. Crack Propagation by Finite Element Method

    OpenAIRE

    H. Ricardo, Luiz Carlos

    2017-01-01

    Crack propagation simulation began with the development of the finite element method; the analyses were conducted to obtain a basic understanding of the crack growth. Today structural and materials engineers develop structures and materials properties using this technique. The aim of this paper is to verify the effect of different crack propagation rates in determination of crack opening and closing stress of an ASTM specimen under a standard suspension spectrum loading from FD&E SAE Keyh...

  2. Photoelectric elements of the eclipsing binary XY Ceti

    International Nuclear Information System (INIS)

    Srivastava, R.K.; Padalia, T.D.

    1975-01-01

    The absolute elements of the system XY Ceti have been obtained on the basis of the spectroscopic elements given by Popper (1971) and the photoelectric elements derived previously. The colours of the components have been obtained. Both components are found to lie fairly on the Main Sequence. The primary component of the system, however, is slightly more evolved as it shows a tendency to drift away from the Main Sequence. The spectral classes now assigned are A5V (primary) and A7V (secondary). The values of Roche constants indicate that the system is a detached one. (Auth.)

  3. Joining elements of silicon carbide

    International Nuclear Information System (INIS)

    Olson, B.A.

    1979-01-01

    A method of joining together at least two silicon carbide elements (e.g.in forming a heat exchanger) is described, comprising subjecting to sufficiently non-oxidizing atmosphere and sufficiently high temperature, material placed in space between the elements. The material consists of silicon carbide particles, carbon and/or a precursor of carbon, and silicon, such that it forms a joint joining together at least two silicon carbide elements. At least one of the elements may contain silicon. (author)

  4. Intermediate coupling collision strengths from LS coupled R-matrix elements

    International Nuclear Information System (INIS)

    Clark, R.E.H.

    1978-01-01

    Fine structure collision strength for transitions between two groups of states in intermediate coupling and with inclusion of configuration mixing are obtained from LS coupled reactance matrix elements (R-matrix elements) and a set of mixing coefficients. The LS coupled R-matrix elements are transformed to pair coupling using Wigner 6-j coefficients. From these pair coupled R-matrix elements together with a set of mixing coefficients, R-matrix elements are obtained which include the intermediate coupling and configuration mixing effects. Finally, from the latter R-matrix elements, collision strengths for fine structure transitions are computed (with inclusion of both intermediate coupling and configuration mixing). (Auth.)

  5. Detection of staphylococcal cassette chromosome mec type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes in human clinical isolates of clonal complex 130 methicillin-resistant Staphylococcus aureus.

    LENUS (Irish Health Repository)

    Shore, Anna C

    2011-08-01

    Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec (SCCmec) elements. In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. The isolates were identified as methicillin-susceptible S. aureus using the GeneXpert real-time PCR assay. Whole-genome sequencing of one isolate (M10\\/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ-mecA-mecR1-mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). The SCCmec element was almost identical to that of SCCmec type XI (SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The open reading frames (ORFs) identified within SCCmec XI of M10\\/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. A third DR was identified ca. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. aureus strains were predominantly from bovine sources. The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon.

  6. Trace element emissions from coal

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-09-15

    Trace elements are emitted during coal combustion. The quantity, in general, depends on the physical and chemical properties of the element itself, the concentration of the element in the coal, the combustion conditions and the type of particulate control device used, and its collection efficiency as a function of particle size. Some trace elements become concentrated in certain particle streams following combustion such as bottom ash, fly ash, and flue gas particulate matter, while others do not. Various classification schemes have been developed to describe this partitioning behaviour. These classification schemes generally distinguish between: Class 1: elements that are approximately equally concentrated in the fly ash and bottom ash, or show little or no fine particle enrichment, examples include Mn, Be, Co and Cr; Class 2: elements that are enriched in the fly ash relative to bottom ash, or show increasing enrichment with decreasing particle size, examples include As, Cd, Pb and Sb; Class 3: elements which are emitted in the gas phase (primarily Hg (not discussed in this review), and in some cases, Se). Control of class 1 trace elements is directly related to control of total particulate matter emissions, while control of the class 2 elements depends on collection of fine particulates. Due to the variability in particulate control device efficiencies, emission rates of these elements can vary substantially. The volatility of class 3 elements means that particulate controls have only a limited impact on the emissions of these elements.

  7. REACTOR FUEL ELEMENTS TESTING CONTAINER

    Science.gov (United States)

    Whitham, G.K.; Smith, R.R.

    1963-01-15

    This patent shows a method for detecting leaks in jacketed fuel elements. The element is placed in a sealed tank within a nuclear reactor, and, while the reactor operates, the element is sparged with gas. The gas is then led outside the reactor and monitored for radioactive Xe or Kr. (AEC)

  8. Vibration Analysis of Circular Arch Element Using Curvature

    Directory of Open Access Journals (Sweden)

    H. Saffari

    2008-01-01

    Full Text Available In this paper, a finite element technique was used to determine the natural frequencies, and the mode shapes of a circular arch element was based on the curvature, which can fully represent the bending energy and by the equilibrium equations, the shear and axial strain energy were incorporated into the formulation. The treatment of general boundary conditions dose need a consideration when the element is incorporated by the curvature-based formula. This can be obtained by the introduction of a transformation matrix between nodal curvatures and nodal displacements. The equation of the motion for the element was obtained by the Lagrangian equation. Four examples are presented in order to verify the element formulation and its analytical capability.

  9. Accelerator vacuum system elements

    International Nuclear Information System (INIS)

    Sivokon', V.V.; Kobets, A.F.; Shvetsov, V.A.; Sivokon', L.V.

    1980-01-01

    Some elements of vacuum systems are investigated. Considerable attention has been given to the investigation into peculiarities in pumping out of a ionoguide for transportation of an accelerated charged particles beam the spread of which often attains a considerable length. The number of pumps over the ionoguide length is experimentally determined. It is shown that as a result of ionoguide warm-up the pumping out time is considerably reduced maximum permissible pressure is decreased by two orders and lesser rate of pump pumping out is required. The investigations have shown that when operating the ionoguide there is no necessity in setting up seals between the ionoguide and magnetodischarged pump. The causes of the phenomenon in which the pressure near the pump is greater than in the end of the ionoguide, are impurities carried in by the pump into the ionoguide volume and the pumping out capacity of the pressure converter

  10. Ucla, escuela elemental

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1962-03-01

    Full Text Available La Escuela Elemental de Preparación de la Universidad de California, en Los Angeles, está dedicada a la educación e investigación y preparación del profesorado de la infancia. Se ha construido en un paraje maravilloso, de frondosa vegetación, frente a un terreno bastante quebrado, circunstancia que presta mayor encanto al conjunto, construido con gran pericia y adaptación al paisaje a base de una dominante horizontalidad, con materiales sencillos (ladrillos, hierro y madera y gran comunicación con la naturaleza mediante grandes cristaleras correderas que ensanchan las clases y las suplementan hacia el jardín de acuerdo con las nuevas normas y prácticas docentes.

  11. Improved nuclear fuel element

    International Nuclear Information System (INIS)

    1974-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed and has a metal liner disposed between the cladding and the nuclear fuel material and a high lubricity material in the form of a coating disposed between the liner and the cladding. The liner preferably has a thickness greater than the longest fission product recoil distance and is composed of a low neutron capture cross-section material. The liner is preferably composed of zirconium, an alloy of zirconium, niobium or an alloy of niobium. The liner serves as a preferential reaction site for volatile impurities and fission products and protects the cladding from contact and reaction with such impurities and fission products. The high lubricity material acts as an interface between the liner and the cladding and reduces localized stresses on the cladding due to fuel expansion and cracking of the fuel

  12. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Obara, Hiroshi.

    1981-01-01

    Purpose: To suppress iodine release thereby prevent stress corrosion cracks in fuel cans by dispersing ferrous oxide at the outer periphery of sintered uranium dioxide pellets filled and sealed within zirconium alloy fuel cans of fuel elements. Constitution: Sintered uranium dioxide pellets to be filled and sealed within a zirconium alloy fuel can are prepared either by mixing ferric oxide powder in uranium dioxide powder, sintering and then reducing at low temperature or by mixing iron powder in uranium dioxide powder, sintering and then oxidizing at low temperature. In this way, ferrous oxide is dispersed on the outer periphery of the sintered uranium dioxide pellets to convert corrosive fission products iodine into iron iodide, whereby the iodine release is suppressed and the stress corrosion cracks can be prevented in the fuel can. (Moriyama, K.)

  13. Nuclear fuel element

    International Nuclear Information System (INIS)

    Hirama, H.

    1978-01-01

    A nuclear fuel element comprises an elongated tube having upper and lower end plugs fixed to both ends thereof and nuclear fuel pellets contained within the tube. The fuel pellets are held against the lower end plug by a spring which is supported by a setting structure. The setting structure is maintained at a proper position at the middle of the tube by a wedge effect caused by spring force exerted by the spring against a set of balls coacting with a tapered member of the setting structure thereby wedging the balls against the inner wall of the tube, and the setting structure is moved free by pushing with a push bar against the spring force so as to release the wedge effect

  14. Finite element modelling

    International Nuclear Information System (INIS)

    Tonks, M.R.; Williamson, R.; Masson, R.

    2015-01-01

    The Finite Element Method (FEM) is a numerical technique for finding approximate solutions to boundary value problems. While FEM is commonly used to solve solid mechanics equations, it can be applied to a large range of BVPs from many different fields. FEM has been used for reactor fuels modelling for many years. It is most often used for fuel performance modelling at the pellet and pin scale, however, it has also been used to investigate properties of the fuel material, such as thermal conductivity and fission gas release. Recently, the United Stated Department Nuclear Energy Advanced Modelling and Simulation Program has begun using FEM as the basis of the MOOSE-BISON-MARMOT Project that is developing a multi-dimensional, multi-physics fuel performance capability that is massively parallel and will use multi-scale material models to provide a truly predictive modelling capability. (authors)

  15. Heavy-element research

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    The status is reported of studies on the solid-state chemistry of the actinides and lanthanides, spectroscopy of actinide compounds, and dynamic chemical description of actinide elements in solution. Phase studies were done on Rb 2 UO 4 , K 2 UO 4 , Li 2 UO 4 , and Es 2 U 2 O 7 . The lithium neptunate (VI) system was investigated and the existence of Li 2 NpO 4 was established. In oxidation-reduction studies it was shown that Am(III) can be electrolytically oxidized to Am(IV) in strong H 3 PO 4 , but Cf(III) and Pr(III) do not oxidize. The low-temperature absorption spectrum of thin films of NpBr 3 was investigated. (U.S.)

  16. ELEMENTAL FORMS OF HOSPITALITY

    Directory of Open Access Journals (Sweden)

    Maximiliano Emanuel Korstanje

    2010-11-01

    Full Text Available Modern studies emphasized on the needs of researching the hospitality as relevant aspects of tourism and hospitality fields. Anyway, these approaches are inextricably intertwined to the industry of tourism and do not take seriously the anthropological and sociological roots of hospitality. In fact, the hotel seems to be a partial sphere of hospitality at all. Under this context, the present paper explores the issue of hospitality enrooted in the political and economic indo-European principle of free-transit which is associated to a much broader origin.  Starting from the premise etymologically hostel and hospital share similar origins, we follow the contributions of J Derrida to determine the elements that formed the hospitality up to date.

  17. Photo-switching element

    Energy Technology Data Exchange (ETDEWEB)

    Masaki, Yuichi

    1987-10-31

    Photo-input MOS transistor (Photo-switching element) cannot give enough ON/OFF ratio but requires an auxiliary condenser for a certain type of application. In addition, PN junction of amorphous silicon is not practical because it gives high leak current resulting in low electromotive force. In this invention, a solar cell was constructed with a lower electrode consisting of a transparent electro-conducting film, a photosensitive part consisting of an amorphous Si layer of p-i-n layer construction, and an upper metal electrode consisting of Cr or Nichrome, and a thin film transistor was placed on the solar cell, and further the upper metal electrode was co-used as a gate electrode of the thin film transistor; this set-up of this invention enabled to attain an efficient photo-electric conversion of the incident light, high electromotive force of the solar cell, and the transistor with high ON/OFF ratio. (3 figs)

  18. Managing structural design through integrated models and obtaining increased safety and economy

    International Nuclear Information System (INIS)

    Diaz, B.E.; Thomaz, E.C.S.

    1987-01-01

    The use of large finite element (FE) models for the design of reinforced concrete elements in nuclear power plants will be treated. For this technique a set of computer programs is necessary, since the amount of data is very large. With this design method a series of advantages is obtained such as: reduction of reinforcing steel expenditure, increase of safety through a better representation of the structures, an adequate control of the calculation due to the transparent method of design, reduction of design time due to the automatic computation and so on. (author)

  19. A comparison of specific effective energies values obtained for some radioactive element using 3 different decay data banks

    International Nuclear Information System (INIS)

    Nascimento, J.E.C.; Bertelli Neto, L.

    1990-01-01

    The Specific Effective Energies (SEE) are the dose equivalents received by each of the body organs (targets organs) per nuclear transformation of a radionuclide deposited in an organ or tissue (source organ) after an intake of this isotope. The SEE values were calculated on basis of the dosimetric concepts of Publication 30 of the International Comission on Radiological Protection (ICRP). The results were evaluated using two of the three most known decay data banks. This study shows considerables discrepancies in the evaluation of the SEE values for some radionuclides. In theses cases it is recommended the use of the most complete and detailed decay data bank to perform the SEE calculations. (author) [pt

  20. Review of the experimental results on impurity centers in elemental semiconductors obtained by μSR and other techniques

    International Nuclear Information System (INIS)

    Estle, T.L.

    1980-01-01

    Selected electron paramagnetic resonance studies of defect centers in group IV semiconductors are reviewed. Features of this research which are useful in analyzing the nature of normal and anomalous muonium (Mu and Mu*) in these crystals are pointed out, and a moderately specific model of Mu and Mu* is presented and compared to studies of hydrogen in silicon and germanium

  1. Pre-irradiation testing of experimental fuel elements

    International Nuclear Information System (INIS)

    Basova, B.G.; Davydov, E.F.; Dvoretskij, V.G.; Ivanov, V.B.; Syuzev, V.N.; Timofeev, G.A.; Tsykanov, V.A.

    1979-01-01

    The problems of testing of experimental fuel elements of nuclear reactors on the basis of complex accountancy of the factors defining operating capacity of the fuel elements are considered. The classification of the parameters under control and the methods of initial technological testing, including testing of the fuel product, cladding and fished fuel element, is given. The requirements to the apparatus used for complex testing are formulated. One of the possible variants of representation of the information obtained in the form of the input certificate of a single fuel element under study is proposed. The processing flowsheet of the gathered information using the computer is given. The approach under consideration is a methodological basis of investigation of fuel element operating life at the testing stage of the experimental fuel elements

  2. Evaluation of trace element status of food articles

    International Nuclear Information System (INIS)

    Qureshi, I.H.; Ahmad, S.; Zaidi, S.J.; Mannan, A.; Waheed, S.; Fatima, I.; Arif, M.; Rahman, A.

    1996-01-01

    Food is the main source of major, minor and micro nutrients required for human beings. Food articles, due to environmental pollution may also contain some toxic elements which would adversely affect their health. In order to assess the adequacy and safety of human diet main food items were analyzed for the measurement of essential and toxic trace elements employing neutron activation analysis and atomic absorption spectrometry. The data so obtained will serve as baseline values and will be helpful to monitor the changes in the trace element contents of these items in future. The dietary intake of essential and toxic trace elements through these items was estimated and compared with the recommended values. This study indicates that the intake of essential elements except for co is fairly adequate and that of toxic elements in well well within the permissible limits. (author)

  3. Stress-compatible embedded cohesive crack in CST element

    DEFF Research Database (Denmark)

    Olesen, John Forbes; Poulsen, Peter Noe

    2010-01-01

    A simple element with an embedded strong discontinuity for modeling cohesive cracking of concrete is presented. The element differs from previous elements of the embedded type, in that a consistent stress field is obtained by direct enforcement of stress continuity across the crack....... The displacement discontinuity is modeled in an XFEM fashion; however, the discontinuous displacement field is special, allowing for the direct enforcement of stress continuity. This in turn allows for elimination of extra degrees of freedom necessary for describing the crack deformations, thus the element has...... the same number of freedoms as its continuous basis: CST. The good performance of the element is demonstrated by its ability to simulate threepoint bending of a notched concrete beam. The advantage of the element is its simplicity and the straightforward implementation of it. Handling situations...

  4. The Chemistry of Superheavy Elements

    CERN Document Server

    Schädel, M

    2003-01-01

    The chemistry of transactinide or superheavy elements has reached element 108. Preparations are under way to leap to element 112 and beyond. The current status of this atom-at-a-time chemical research and its future perspectives are reviewed from an experimental point of view together with some of the interesting results from n -rich nuclides near and at the N=162 neutron shell. Experimental techniques and important results enlightening typical chemical properties of elements 104 through 108 are presented in an exemplary way. From the results of these experiments it is justified to place these elements in the Periodic Table of the Elements in to groups 4 through 8, respectively. However, mainly due to the influence of relativistic effects, it is no longer possible to deduce detailed chemical properties of these superheavy elements simply from this position.

  5. Transplutonium elements - a literature survey

    International Nuclear Information System (INIS)

    Sivaramakrishnan, C.K.; Jadhav, A.V.

    1974-01-01

    The report surveys reported work on the discovery of transplutonium elements and their production through various methods like bombardment of heavy elements with charged ions, successive neutron captures on heavy elements in reactors and multiple neutron captures by heavy elements during nuclear explosions. Estimated yields of transplutonium elements in special targets irradiated in reactors, and also as byproducts from spent power reactor fuels are quoted. Various chemical procedures adopted for recovery of these elements from irradiated target and also from power reactor fuel reprocessing streams are described. A brief survey of shielded facilities available at various centres for transplutonium programmes is also included. Major uses of some of these heavy elements are described. (author)

  6. Dissipation element analysis of turbulent scalar fields

    International Nuclear Information System (INIS)

    Wang Lipo; Peters, Norbert

    2008-01-01

    Dissipation element analysis is a new approach for studying turbulent scalar fields. Gradient trajectories starting from each material point in a scalar field Φ'(x-vector,t) in ascending directions will inevitably reach a maximal and a minimal point. The ensemble of material points sharing the same pair ending points is named a dissipation element. Dissipation elements can be parameterized by the length scale l and the scalar difference Δφ ', which are defined as the straight line connecting the two extremal points and the scalar difference at these points, respectively. The decomposition of a turbulent field into dissipation elements is space-filling. This allows us to reconstruct certain statistical quantities of fine scale turbulence which cannot be obtained otherwise. The marginal probability density function (PDF) of the length scale distribution based on a Poisson random cutting-reconnection process shows satisfactory agreement with the direct numerical simulation (DNS) results. In order to obtain the further information that is needed for the modeling of scalar mixing in turbulence, such as the marginal PDF of the length of elements and all conditional moments as well as their scaling exponents, there is a need to model the joint PDF of l and Δφ ' as well. A compensation-defect model is put forward in this work to show the dependence of Δφ ' on l. The agreement between the model prediction and DNS results is satisfactory, which may provide another explanation of the Kolmogorov scaling and help to improve turbulent mixing models. Furthermore, intermittency and cliff structure can also be related to and explained from the joint PDF.

  7. Characterization of the liquid products obtained in tyre pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Laresgoiti, M.F.; Caballero, B.M.; De Marco, I.; Torres, A.; Cabrero, M.A.; Chomon, M.J. [Escuela Superior de Ingenieros de Bilbao, Alda. Urquijo s/n, Bilbao 48013 (Spain)

    2004-06-01

    Cross-section samples (2-3cm wide), representative of a whole car tyre, have been pyrolysed under nitrogen in a 3.5dm{sup 3} autoclave at 300, 400, 500, 600 and 700C. Over 500C there is no effect of temperature on gases and liquids yields ({approx}17 and 38%, respectively). Tyre pyrolysis liquids have been characterized, including elemental analysis, gross calorific value (GCV), gas chromatography/mass spectroscopy (GC/MS) and distillation. Tyre derived liquids are a complex mixture of C{sub 6}-C{sub 24} organic compounds, with a lot of aromatics (53.4-74.8%), some nitrogenated (2.47-3.5%) and some oxygenated compounds (2.29-4.85%). They have GCV (42MJkg{sup -1}) even higher than those specified for commercial heating oils, but sulphur contents (1-1.4%) near or slightly over the law limit value. Significant quantities of valuable light hydrocarbons such as benzene, toluene, xylene, limonene, etc. were obtained. The concentration of these compounds increase with temperature up to 500C and then decrease. There are an important proportion of polycyclic aromatics such as naphthalenes, phenanthrenes, fluorenes, diphenlys, etc.; their concentration as well as that of total aromatics increases significantly with temperature. Distillation data of the 500C oils showed that {approx}20% have the boiling range of light naphtha (<160C), {approx}10% of heavy naphtha (160-204C) and {approx}35% of middle distillate (204-350C). As far as distillation data are concerned, the tyre oil fractions with the same boiling range as commercial automotive diesel oils and heating diesel oils fulfil the present specifications of such commercial products.

  8. Finite element coiled cochlea model

    Science.gov (United States)

    Isailovic, Velibor; Nikolic, Milica; Milosevic, Zarko; Saveljic, Igor; Nikolic, Dalibor; Radovic, Milos; Filipović, Nenad

    2015-12-01

    Cochlea is important part of the hearing system, and thanks to special structure converts external sound waves into neural impulses which go to the brain. Shape of the cochlea is like snail, so geometry of the cochlea model is complex. The simplified cochlea coiled model was developed using finite element method inside SIFEM FP7 project. Software application is created on the way that user can prescribe set of the parameters for spiral cochlea, as well as material properties and boundary conditions to the model. Several mathematical models were tested. The acoustic wave equation for describing fluid in the cochlea chambers - scala vestibuli and scala timpani, and Newtonian dynamics for describing vibrations of the basilar membrane are used. The mechanical behavior of the coiled cochlea was analyzed and the third chamber, scala media, was not modeled because it does not have a significant impact on the mechanical vibrations of the basilar membrane. The obtained results are in good agreement with experimental measurements. Future work is needed for more realistic geometry model. Coiled model of the cochlea was created and results are compared with initial simplified coiled model of the cochlea.

  9. Characteristic analysis on moderating material for obtaining epithermal neutron beam

    International Nuclear Information System (INIS)

    Jiang Xinbiao; Chen Da; Zhang Ying

    2000-01-01

    The one dimension discrete coordinates transport code ANISN was used to calculate three-group constants of 11 elements which could be used to consist moderating epithermal neutron material of beam. Moderating character of simple substances, compounds and mixtures consisted of the optimized elements analyzed three kinds of moderating materials were optimized for epithermal neutron beam

  10. Radioactive elements found in plants contaminated by radioactive rain

    Energy Technology Data Exchange (ETDEWEB)

    Tanidazawa, M; Ishihara, T

    1954-01-01

    Ashes obtained from contaminated trifolium repens, astragalus sinicus, and rumex japonicus were studied. The precipitate obtained by treating the acidic solution of the ash with H/sub 2/S followed by Fe/sup + +/ in the presence of NH/sub 3/ and NH/sub 4/Cl contained Y, Sr, and the rare earth elements.

  11. EAF optimal managing elements

    Science.gov (United States)

    Ioana, A.; Constantin, N.; Dragna, E. C.

    2017-01-01

    Electric Arc Furnaces (EAF) is an important and complex aggregate. We present elements of EAF operating efficiency. The reliability of the EAF is mainly determined by electric circuit reliability and especially of the transformator of the furnace. This due to the fact that, in an electric steel plant, the objective „24 tapping/day” involves. Due to the complexity of the process, the EAF operation needs a computer usage and, in his componence, it must have two independent calculation units (UC1) and (UC2). Based on these two input sets (Σi1) and ((Σi2), the calculation unit (UC1) builds the general operation procedure based on mathematical methods. For that purpose, there are used the results of the 5 mathematical methods: the mathematical model to write-off the function objective (M.F.O.); the mathematical model of calculating the charge (M.C.C.); the mathematical model of conducting the effective melt (M.C.M.); the mathematical model of reheating the charge (M.R.C.); the mathematical model of blasting the reactive dusts (M.B.R.D.).

  12. Nuclear fuel element

    International Nuclear Information System (INIS)

    Armijo, J.S.

    1977-01-01

    A nuclear fuel element for use in the core of a nuclear reactor is disclosed which has a composite cladding having a substrate, a metal barrier metallurgically bonded to the inside surface of the substrate and an inner layer metallurgically bonded to the inside surface of the metal barrier. In this composite cladding, the inner layer and the metal barrier shield the substrate from any impurities or fission products from the nuclear fuel material held within the composite cladding. The metal barrier forms about 1 to about 4 percent of the thickness of the cladding and is comprised of a metal selected from the group consisting of niobium, aluminum, copper, nickel, stainless steel, and iron. The inner layer and then the metal barrier serve as reaction sites for volatile impurities and fission products and protect the substrate from contact and reaction with such impurities and fission products. The substrate and the inner layer of the composite cladding are selected from conventional cladding materials and preferably are a zirconium alloy. Also in a preferred embodiment the substrate and the inner layer are comprised of the same material, preferably a zirconium alloy. 19 claims, 2 figures

  13. Neutron absorbing element

    International Nuclear Information System (INIS)

    Kasai, Shigeo.

    1991-01-01

    The present invention concerns a neutron absorbing element of a neutron shielding member used for an LMFBR type reactor. The inside of a fuel can sealed at both of the upper and the lower ends thereof with plugs is partitioned into an upper and a lower chambers by an intermediate plug. A discharging hole is disposed at the upper end plug, which is in communication with the outside. A communication tube is disposed at the intermediate end plug and it is in communication with the lower chamber containing B 4 C pellets. A cylindrical support member having three porous plugs connected in series is disposed at the lower surface of the discharging hole provided at the upper end plug. Further, the end of the discharging hole is sealed with high temperature solder and He atmosphere is present at the inside of the fuel can. With such a constitution, the supporting differential pressure of the porous plugs can be made greater while discharging He gases generated from B 4 C to the outside. Further, the porous plugs can be surely wetted by coolants. Accordingly, it is possible to increase life time and shorten the size. (I.N.)

  14. Chemistry of transuranium elements

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The half-wave amalgamation potential of No (element 102) was determined. Studies on the preparation and properties of Cf are reported; previously reported results on Es were confirmed. The heat of solution of Bk was measured. Spectroscopic and x-ray diffraction studies of Es-253 bromides are reported. Salicylate complexes with Sm(III), Am(III), Th(IV), and U(IV)O 2 were prepared; crystal data are given. Results of studies on the effect of secondary bonds on the strength of O double bond Np double bond O bonds are reported. The M series x rays of Np were measured. Anomalous spin--orbit splitting of the 4f level in the actinide series is reported. Progress is reported in studies on the Cf oxide system for oxygen pressures up to 760 mm and temperatures between 25 and 1000 0 C, as well as structural parameters of transplutonium oxysulfates and oxysulfides and actinide and lanthanide hydroxides. The electron paramagnetic resonance spectrum of 253 Es 2+ was observed in the cubic monocrystal hosts BaF 2 and SrCl 2

  15. Chemistry of the superheavy elements.

    Science.gov (United States)

    Schädel, Matthias

    2015-03-13

    The quest for superheavy elements (SHEs) is driven by the desire to find and explore one of the extreme limits of existence of matter. These elements exist solely due to their nuclear shell stabilization. All 15 presently 'known' SHEs (11 are officially 'discovered' and named) up to element 118 are short-lived and are man-made atom-at-a-time in heavy ion induced nuclear reactions. They are identical to the transactinide elements located in the seventh period of the periodic table beginning with rutherfordium (element 104), dubnium (element 105) and seaborgium (element 106) in groups 4, 5 and 6, respectively. Their chemical properties are often surprising and unexpected from simple extrapolations. After hassium (element 108), chemistry has now reached copernicium (element 112) and flerovium (element 114). For the later ones, the focus is on questions of their metallic or possibly noble gas-like character originating from interplay of most pronounced relativistic effects and electron-shell effects. SHEs provide unique opportunities to get insights into the influence of strong relativistic effects on the atomic electrons and to probe 'relativistically' influenced chemical properties and the architecture of the periodic table at its farthest reach. In addition, they establish a test bench to challenge the validity and predictive power of modern fully relativistic quantum chemical models. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  16. Empirical Coulomb matrix elements and the mass of 22Al

    International Nuclear Information System (INIS)

    Whitehead, R.R.; Watt, A.; Kelvin, D.; Rutherford, H.J.

    1976-01-01

    An attempt has been made to obtain a set of Coulomb matrix elements which fit the known Coulomb energy shifts in the nuclei of mass 18 to 22. The interaction obtained fits the data well with only a few exceptions, one of these being the Coulomb shift of the notorious third 0 + state in 18 Ne. These Coulomb matrix elements are used together with the Chung-Wildenthal interaction to obtain a new prediction for the mass excess of 22 Al. The results indicate that 22 Al should be bound against proton emission. (Auth.)

  17. Experimental Study of Elements Promoting Mixing in Fuel Elements

    International Nuclear Information System (INIS)

    Silin, Nicolas; Juanico, Luis; Delmastro, Dario

    2003-01-01

    In the present work a thermal tracing technique is used to measure the increase of the mixing between subchannels in the presence of different mixing elements.As representative elements a spacer, a spacer with mixing vanes and turbulence promoter buttons were considered.The performance of these elements was evaluated by studying the behavior of a thermal trace in each case.Also the pressure drop for each case is presented.The results present a qualitative and quantitative guide for the application of each one of these appendages in future nuclear elements

  18. Elements of Dynamic Programming,

    Science.gov (United States)

    1981-02-02

    step/pitch lies in the fact that us ia .o eacerprise P, cf means x". to enter.rise P2 - means xan sc L Jsing widely used teraiAo.j, :onrrol U, it is... acca ~acj ,,L ra sauticn of protlem. Is qenertity intuitively it ii cliax thi-t with at. increat-e in the number aoc = 80151502 FAG E of stips/pitches...Ad.aua inccme W*.. 5S on the ,raph/curve Fig. 9.10 bitn ;.A Leut Z, = 0.75.x2 + 0.3 (Z, - xl); it is obtained value w. 4 . .o.& acca ayq.n they are

  19. A suitable low-order, eight-node tetrahedral finite element for solids

    Energy Technology Data Exchange (ETDEWEB)

    Key, S.W.; Heinstein, M.S.; Stone, C.M.; Mello, F.J.; Blanford, M.L.; Budge, K.G.

    1998-03-01

    To use the all-tetrahedral mesh generation existing today, the authors have explored the creation of a computationally efficient eight-node tetrahedral finite element (a four-node tetrahedral finite element enriched with four mid-face nodal points). The derivation of the element`s gradient operator, studies in obtaining a suitable mass lumping, and the element`s performance in applications are presented. In particular they examine the eight-node tetrahedral finite element`s behavior in longitudinal plane wave propagation, in transverse cylindrical wave propagation, and in simulating Taylor bar impacts. The element samples only constant strain states and, therefore, has 12 hour-glass modes. In this regard it bears similarities to the eight-node, mean-quadrature hexahedral finite element. Comparisons with the results obtained from the mean-quadrature eight-node hexahedral finite element and the four-node tetrahedral finite element are included. Given automatic all-tetrahedral meshing, the eight-node, constant-strain tetrahedral finite element is a suitable replacement for the eight-node hexahedral finite element in those cases where mesh generation requires an inordinate amount of user intervention and direction to obtain acceptable mesh properties.

  20. Banknote authentication using chaotic elements technology

    Science.gov (United States)

    Ambadiyil, Sajan; P. S., Krishnendu; Mahadevan Pillai, V. P.; Prabhu, Radhakrishna

    2017-10-01

    The counterfeit banknote is a growing threat to the society since the advancements in the field of computers, scanners and photocopiers, as they have made the duplication process for banknote much simpler. The fake note detection systems developed so far have many drawbacks such as high cost, poor accuracy, unavailability, lack of user-friendliness and lower effectiveness. One possible solution to this problem could be the use of a system uniquely linked to the banknote itself. In this paper, we present a unique identification and authentication process for the banknote using chaotic elements embedded in it. A chaotic element means that the physical elements are formed from a random process independent from human intervention. The chaotic elements used in this paper are the random distribution patterns of such security fibres set into the paper pulp. A unique ID is generated from the fibre pattern obtained from UV image of the note, which can be verified by any person who receives the banknote to decide whether the banknote is authentic or not. Performance analysis of the system is also studied in this paper.

  1. Synthesis and properties of superheavy elements

    CERN Document Server

    Hofmann, S

    2003-01-01

    The nuclear shell model predicts that the next doubly magic shell-closure beyond sup 2 sup 0 sup 8 Pb is at a proton number Z = 114, 120, or 126 and at a neutron number N = 172 or 184. The outstanding of experimental investigations is the exploration of this region of spherical 'SuperHeavy Elements' (SHEs). Experimental methods are described which allowed for the identification of elements 107 to 112 in studies of cold fusion reactions based on lead and bismuth targets. Also presented are data which were obtained on the synthesis of elements 112, 114, and 116 in investigation of hot fusion reactions using actinide targets. The decay data reveal that for the heaviest elements, the dominant decay mode is alpha emission, not fission. Decay properties as well as reaction cross- sections are compared with the results of theoretical studies. Finally, plans are presented for the further development of the experimental set-up and the application of new techniques. At a higher sensitivity, the exploration of the regio...

  2. Development and evaluation of separation elements

    International Nuclear Information System (INIS)

    Guimaraes, R.R.R.; Rocha, Z.

    1990-01-01

    For industrial testing of the uranium enrichment technology by the jet nozzle process, it is being erected in Resende the 'First Cascade' (FC) and it was built the Separation Element Plant (FES). For the development, optimization and quality control of the separation elements produced by FES, it was set up in CDTN a laboratorial infrastructure. As part of it, it was designed, built and assembled the Separation Slit Testing Equipment (ITRS), with several components developed and constructed in CDTN. The tests are being carried out in ITRS with the objective of adjusting the machine tools of FES used in the line production of the separation elements. From the satisfactory results obtained with these tests, FES will start the production of separation tubes to be installed in FC. The objective of this paper is to describe the operation and evaluation tests in ITRS, as well as to present their contribution to the development and quality control of the separation elements produced in FES. (author) [pt

  3. Variational approach to probabilistic finite elements

    Science.gov (United States)

    Belytschko, T.; Liu, W. K.; Mani, A.; Besterfield, G.

    1991-08-01

    Probabilistic finite element methods (PFEM), synthesizing the power of finite element methods with second-moment techniques, are formulated for various classes of problems in structural and solid mechanics. Time-invariant random materials, geometric properties and loads are incorporated in terms of their fundamental statistics viz. second-moments. Analogous to the discretization of the displacement field in finite element methods, the random fields are also discretized. Preserving the conceptual simplicity, the response moments are calculated with minimal computations. By incorporating certain computational techniques, these methods are shown to be capable of handling large systems with many sources of uncertainties. By construction, these methods are applicable when the scale of randomness is not very large and when the probabilistic density functions have decaying tails. The accuracy and efficiency of these methods, along with their limitations, are demonstrated by various applications. Results obtained are compared with those of Monte Carlo simulation and it is shown that good accuracy can be obtained for both linear and nonlinear problems. The methods are amenable to implementation in deterministic FEM based computer codes.

  4. Monitoring of trace element air pollution

    International Nuclear Information System (INIS)

    Freitas, M.C.; Gouveia, M.A.; Prudencio, M.I.; Ferreira, P.; Morgado, I.; Amaro, A.; Fernandes, T.; Dionisio, I.; Reis, M.A.; Alves, L.C.

    1994-01-01

    With this project, a biomonitoring survey will be carried out with epiphytic lichens. The lichens Parmelia sulcata (or caperata) will be collected from olive trees about 1-2 m above the ground, using a 10x10 km grid or 50x50 km gird. In total, about 300 sampling sites will be set up. Within one sampling site, variations in elemental concentrations of lichen material taken from several trees of the same species will be analyzed to obtained the local variation for each element (made in 10% of the grid). In addition some typical soil samples will be collected so that the contribution of soil suspended in air particulate matter can be recognized. The samples will be analyzed for ∼50 elements by NAA and PIXE. The expected results will be integrated data sets, which will be used in the next step for application of a statistical procedure to identify particular pollution sources. The project also consists of exposure experiments with lichen transplant samples at several sampling sites, which are representative for the regions under study. In addition at each sampling site air particular matter and total deposition will be collected monthly, during 1 year. The aim is to establish a quantitative relationship between results obtained with the lichen transplant samples and with air particulate matter and total deposition. (author). 12 refs, 2 figs, 2 tabs

  5. Analog elements for transuranic chemistries

    International Nuclear Information System (INIS)

    Weimer, W.C.

    1982-01-01

    The analytical technique for measuring trace concentrations of the analog rare earth elements has been refined for optimal detection. The technique has been used to determine the rare earth concentrations in a series of geological and biological materials, including samples harvested from controlled lysimeter investigations. These studies have demonstrated that any of the trivalent rare earth elements may be used as analog elements for the trivalent transuranics, americium and curium

  6. Photoshop Elements 10 For Dummies

    CERN Document Server

    Obermeier, Barbara

    2011-01-01

    Perfect your photos and images with this "focused" guide to the latest version of Photoshop Elements For most of us, the professional-level Photoshop is overkill for our needs. Amateur photographers and photo enthusiasts turn to Photoshop Elements for a powerful but simpler way to edit and retouch their snapshots. Photoshop Elements 10 For Dummies, fully updated and revised for the latest release of this software product, helps you navigate Elements to create, edit, fix, share, and organize the high-quality images you desire. Full color pages bring the techniques to life and make taking great

  7. Elemental transfer from Chinese soil via diet to whole human body

    International Nuclear Information System (INIS)

    Zhu Hongda; Fan Tiqiang; Wu Quan; Liu Qingfen; Zhang Wei

    2007-01-01

    Objective: To calculate elemental transfer coefficients from soil via diet to whole human body and DFs of alkaline earth and alkaline metal elements in these transfers. Methods: Based on the results in this research series, including updated values of elemental dietary intakes and whole body burdens for Chinese adult man as well quoted national elemental background values in Chinese soil, their transfer coefficients and DFs of alkaline earth and alkaline metal elements in these transfers were calculated by using UNSCEAR model and Observed Ratio Method. Results: Both the transfer coefficients of 50 elements and the DF values of alkaline earth elements with Pb and alkaline metal elements in these transfers have been obtained. Conclusion: The obtained P 23 or P 234 were all much less than P 34 for these elements. For the observed elements, the highest P 23 , P 34 and P 234 were for Hg, Ca and Se respectively, while the lowest for Ce, In and Y. The P 23 and P 234 of rare earth elements were all less than those of alkaline metal or alkaline earth elements. All of these DFs for alkaline earth elements were all smaller than 1, with increasing or decreasing atomic order, the DF values of alkaline earth elements for these transfers were successfully decreasing. The DFs of Pb seem to be between Sr and Ba. For alkaline metal element, DF of Rb or Cs from soil to diet was smaller than 1, but that from diet to whole human body more than 1. (authors)

  8. Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby

    Science.gov (United States)

    Devaney, Walter E.

    1987-08-04

    Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.

  9. Improvement of Low-Frequency Sound Field Obtained by an Optimized Boundary

    Institute of Scientific and Technical Information of China (English)

    JING Lu; ZHU Xiao-tian

    2006-01-01

    An approach based on the finite element analysis was introduced to improve low-frequency sound field. The optimized scatters on the wall redistribute the modes of the room and provide effective diffusion of sound field. The frequency response, eigenfrequency, spatial distribution and transient response were calculated. Experimental data were obtained through a 1:5 scaled set up. The results show that the optimized treatment has a positive effect on sound field and the improvement is obvious.

  10. Boson mapping of the shell model algebra obtained from a seniority-dictated similarity transformation

    International Nuclear Information System (INIS)

    Geyer, H.B.

    1986-01-01

    The qualitative ideas put forward by Geyer and Lee are given quantitative content by constructing a similarity transformation which reexpresses the Dyson boson images of the single-j shell fermion operators in terms of seniority bosons. It is shown that the results of Otsuka, Arima, and Iachello, or generalizations thereof which include g bosons or even bosons with J>4, can be obtained in an economic and transparent way without resorting to any comparison of matrix elements

  11. Elements on reactor control

    International Nuclear Information System (INIS)

    Bruna, G.B.

    1998-01-01

    In order to achieve the two-fold goal of maximizing the energy obtained from reactor fuel and ensuring the large flexibility of plant operation in respect to safety regulations and keeping the reactor integrity the control of PWRs is generally based on real time monitoring and analysing of independent neutronic parameters: thermal power release, axial power distribution in the core and temperatures of the primary loop. Two control chains more or less coupled according to the control chosen mode are in charge of the control of these parameters. With the brief history of control in French power reactors the advanced X control mode adopted by Framatome for N4 plants is described in detail. A summary of N4 reactor control and protection system is included

  12. Synchrotron diffraction studies of TiC/FeTi cermets obtained by SHS

    International Nuclear Information System (INIS)

    Contreras, L.; Turrillas, X.; Mas-Guindal, M.J.; Vaughan, G.B.M.; Kvick, A.; Rodriguez, M.A.

    2005-01-01

    TiC/FeTi composites have been obtained in situ by Self-propagating High-temperature Synthesis (SHS) of an intimate mixture of compacted powders of elemental carbon, titanium and iron. The reaction has been followed in real time by X-ray diffraction at the ESRF. The mechanism of the reaction is discussed in terms of the formation of a liquid phase corresponding to the eutectic of the Fe/Ti system prior to the TiC synthesis. Temperatures of reaction have been estimated by correlating thermal expansion coefficients with diffraction peaks shifts. The microstructures obtained by this method, suitable for cutting tools and wear resistant applications, are presented

  13. 32 CFR Appendix B to Part 275 - Obtaining Customer Authorization

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Obtaining Customer Authorization B Appendix B to... OF 1978 Pt. 275, App. B Appendix B to Part 275—Obtaining Customer Authorization A. A DoD law... feasible, obtain the customer's consent. B. Any authorization obtained under paragraph A. of this appendix...

  14. Concentrations of radioactive elements in lunar materials

    Science.gov (United States)

    Korotev, Randy L.

    1998-01-01

    As an aid to interpreting data obtained remotely on the distribution of radioactive elements on the lunar surface, average concentrations of K, U, and Th as well as Al, Fe, and Ti in different types of lunar rocks and soils are tabulated. The U/Th ratio in representative samples of lunar rocks and regolith is constant at 0.27; K/Th ratios are more variable because K and Th are carried by different mineral phases. In nonmare regoliths at the Apollo sites, the main carriers of radioactive elements are mafic (i.e., 6-8 percent Fe) impact-melt breccias created at the time of basin formation and products derived therefrom.

  15. Trace element distribution in geological crystals

    Energy Technology Data Exchange (ETDEWEB)

    Den Besten, J L; Jamieson, D N; Weiser, P S [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1997-12-31

    Channelling is a useful microprobe technique for determining the structure of crystals, but until now has not been performed on geological crystals. The composition has been investigated rather than the structure, which can further explain the origin of the crystal and provide useful information on the substitutionality of trace elements. This may then lead to applications of extraction of valuable metals and semiconductor electronics. Natural crystals of pyrite, FeS{sub 2}, which contains a substantial concentration of gold were channeled and examined to identify the channel axis orientation. Rutherford Backscattering (RBS) and Particle Induced X-Ray Emission (PIXE) spectra using MeV ions were obtained in the experiment to provide a comparison of lattice and non-lattice trace elements. 3 figs.

  16. Trace element distribution in geological crystals

    Energy Technology Data Exchange (ETDEWEB)

    Den Besten, J.L.; Jamieson, D.N.; Weiser, P.S. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Channelling is a useful microprobe technique for determining the structure of crystals, but until now has not been performed on geological crystals. The composition has been investigated rather than the structure, which can further explain the origin of the crystal and provide useful information on the substitutionality of trace elements. This may then lead to applications of extraction of valuable metals and semiconductor electronics. Natural crystals of pyrite, FeS{sub 2}, which contains a substantial concentration of gold were channeled and examined to identify the channel axis orientation. Rutherford Backscattering (RBS) and Particle Induced X-Ray Emission (PIXE) spectra using MeV ions were obtained in the experiment to provide a comparison of lattice and non-lattice trace elements. 3 figs.

  17. Superconductivity from magnetic elements under high pressure

    International Nuclear Information System (INIS)

    Shimizu, Katsuya; Amaya, Kiichi; Suzuki, Naoshi; Onuki, Yoshichika

    2006-01-01

    Can we expect the appearance of superconductivity from magnetic elements? In general, superconductivity occurs in nonmagnetic metal at low temperature and magnetic impurities destroy superconductivity; magnetism and superconductivity are as incompatible as oil and water. Here, we present our experimental example of superconducting elements, iron and oxygen. They are magnetic at ambient pressure, however, they become nonmagnetic under high pressure, then superconductor at low temperature. What is the driving force of the superconductivity? Our understanding in the early stages was a simple scenario that the superconductive state was obtained as a consequence of an emergence of the nonmagnetic states. In both cases, we may consider another scenario for the appearance of superconductivity; the magnetic fluctuation mechanism in the same way as unconventional superconductors

  18. Finite element computation of plasma equilibria

    International Nuclear Information System (INIS)

    Rivier, M.

    1977-01-01

    The applicability of the finite element method is investigated for the numerical solution of the nonlinear Grad-Shafranov equation with free boundary for the flux function of a plasma at equilibrium. This method is based on the case of variational principles and finite dimensional subspaces whose elements are piecewise polynomial functions obtained by a Lagrange type interpolation procedure over a triangulation of the domain. Two cases of plasma pressure (exponential and quadratic including a vacuum region) were examined. In both cases the nonuniqueness of the solutions was shown in exhibiting a deeper solution in the case of exponential pressure function, and a non-constant solution for a quadratic pressure function. In order to get this ''other'' solution, two linearization methods were tested with two different constraints. Different cross sections are investigated

  19. Origin and distribution of the elements

    International Nuclear Information System (INIS)

    Pagel, B.E.J.

    1987-01-01

    In the solar neighborhood they have mass fractions of about 70% hydrogen, 28% helium and 1 or 2% heavier elements, mostly O, C, Ne, N, Mg, Si, Fe. Most of the helium comes from nucleosynthesis in the Big Bang, which also produced traces of D, 3 He and 7 Li, while the remainder can largely be accounted for by synthesis in stars and subsequent ejection into the interstellar medium in the form of supernova ejecta, planetary nebulae and stellar winds. Information about these processes can be obtained on the one hand by theoretical computations and observations of stars in advanced stages of evolution and on the other by studying the distribution of detectable elements in different parts of different galaxies and in different stellar populations. Some observational results bearing on the extrapolation of observed abundances back to the Big Bang, and on the evolution of galaxies, are described

  20. A sensor element for direct radiation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Bajons, P.; Wernhart, U.; Zeiler, H. [University of Vienna (Austria). Institut of Material Physics

    1998-08-01

    A combination of a photodiode with a nonimaging light concentrator is developed to perform measurements of the direct solar radiation component. A prototype composed of low price elements is taken as a starting point to discuss the problems which must be faced when calibrating such sensors. By this the influence of the angle of incidence and spectral distribution (caused by different air mass or varying degree of clearness) of the incident radiation on the behavior of the system is studied. The readings are compared to the calculated (global minus diffuse) readings obtained from two standard star pyranometers. Finally the possibilities for increasing the accuracy of the sensor element and for applying the device are discussed. (author)

  1. Representation of the Coulomb Matrix Elements by Means of Appell Hypergeometric Function F 2

    Science.gov (United States)

    Bentalha, Zine el abidine

    2018-06-01

    Exact analytical representation for the Coulomb matrix elements by means of Appell's double series F 2 is derived. The finite sum obtained for the Appell function F 2 allows us to evaluate explicitly the matrix elements of the two-body Coulomb interaction in the lowest Landau level. An application requiring the matrix elements of Coulomb potential in quantum Hall effect regime is presented.

  2. Rare-earth elements

    Science.gov (United States)

    Van Gosen, Bradley S.; Verplanck, Philip L.; Seal, Robert R.; Long, Keith R.; Gambogi, Joseph; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    The rare-earth elements (REEs) are 15 elements that range in atomic number from 57 (lanthanum) to 71 (lutetium); they are commonly referred to as the “lanthanides.” Yttrium (atomic number 39) is also commonly regarded as an REE because it shares chemical and physical similarities and has affinities with the lanthanides. Although REEs are not rare in terms of average crustal abundance, the concentrated deposits of REEs are limited in number.Because of their unusual physical and chemical properties, the REEs have diverse defense, energy, industrial, and military technology applications. The glass industry is the leading consumer of REE raw materials, which are used for glass polishing and as additives that provide color and special optical properties to the glass. Lanthanum-based catalysts are used in petroleum refining, and cerium-based catalysts are used in automotive catalytic converters. The use of REEs in magnets is a rapidly increasing application. Neodymium-iron-boron magnets, which are the strongest known type of magnets, are used when space and weight are restrictions. Nickel-metal hydride batteries use anodes made of a lanthanum-based alloys.China, which has led the world production of REEs for decades, accounted for more than 90 percent of global production and supply, on average, during the past decade. Citing a need to retain its limited REE resources to meet domestic requirements as well as concerns about the environmental effects of mining, China began placing restrictions on the supply of REEs in 2010 through the imposition of quotas, licenses, and taxes. As a result, the global rare-earth industry has increased its stockpiling of REEs; explored for deposits outside of China; and promoted new efforts to conserve, recycle, and substitute for REEs. New mine production began at Mount Weld in Western Australia, and numerous other exploration and development projects noted in this chapter are ongoing throughout the world.The REE-bearing minerals are

  3. Linear finite element method for one-dimensional diffusion problems

    Energy Technology Data Exchange (ETDEWEB)

    Brandao, Michele A.; Dominguez, Dany S.; Iglesias, Susana M., E-mail: micheleabrandao@gmail.com, E-mail: dany@labbi.uesc.br, E-mail: smiglesias@uesc.br [Universidade Estadual de Santa Cruz (LCC/DCET/UESC), Ilheus, BA (Brazil). Departamento de Ciencias Exatas e Tecnologicas. Laboratorio de Computacao Cientifica

    2011-07-01

    We describe in this paper the fundamentals of Linear Finite Element Method (LFEM) applied to one-speed diffusion problems in slab geometry. We present the mathematical formulation to solve eigenvalue and fixed source problems. First, we discretized a calculus domain using a finite set of elements. At this point, we obtain the spatial balance equations for zero order and first order spatial moments inside each element. Then, we introduce the linear auxiliary equations to approximate neutron flux and current inside the element and architect a numerical scheme to obtain the solution. We offer numerical results for fixed source typical model problems to illustrate the method's accuracy for coarse-mesh calculations in homogeneous and heterogeneous domains. Also, we compare the accuracy and computational performance of LFEM formulation with conventional Finite Difference Method (FDM). (author)

  4. Trace Elements in Apple Fruits of Several Regions in the Republic of Macedonia

    International Nuclear Information System (INIS)

    Boev, Blazho; Lepitkova, Sonja; Paneva-Zajkova, Vesna; Georgiev, Lazar

    2006-01-01

    Determination of macro elements and trace elements in apple fruits was carried out by ICP-AES method. Apples were picked up fresh in December 2005. Seven different types of apples from different parts of the country were selected. Apples were sliced into large pieces, dried, and after grinding were dissolved in nitric acid (HNO 3 ) and hydroperoxide (H 2 O 2 ). After digestion, multi-element analysis was carried out. Data obtained were compared to published values for trace elements in apples in other regions of the world. Data obtained indicated that the concentration of trace elements in apples were within the values and data in other regions of the world. (Author)

  5. Rack for nuclear fuel elements

    International Nuclear Information System (INIS)

    Rubinstein, H.J.; Gordon, C.B.; Robison, A.; Clark, P.M.

    1977-01-01

    Disclosed is a rack for storing spent nuclear fuel elements in which a plurality of aligned rows of upright enclosures of generally square cross-sectional areas contain vertically disposed spent fuel elements. Each fuel element is supported at the lower end thereof by a respective support that rests on the floor of the spent fuel pool for a nuclear power plant. An open rack frame is employed as an upright support for the enclosures containing the spent fuel elements. Legs at the lower corners of the frame rest on the floor of the pool to support the frame. In one exemplary embodiment, the support for the fuel element is in the form of a base on which a fuel element rests and the base is supported by legs. In another exemplary embodiment, each fuel element is supported on the pool floor by a self-adjusting support in the form of a base on which a fuel element rests and the base rests on a ball or swivel joint for self-alignment. The lower four corners of the frame are supported by legs adjustable in height for leveling the frame. Each adjustable frame leg is in the form of a base resting on the pool floor and the base supports a threaded post. The threaded post adjustably engages a threaded column on which rests the lower end of the frame. 16 claims, 14 figures

  6. Thermal insulation of fuel elements

    International Nuclear Information System (INIS)

    Dubrovcak, P.; Pec, V.; Pitonak, J.

    1978-01-01

    The claim of the invention concerns thermal insulation of fuel elements heated for measurement of uranium fuel physical properties. For this, layers of aluminium film and of glass fibre are wound onto the inner tube of the element cladding. The space between the inner and the outer tubes is evacuated and the tubes are spaced using spacer wires. (M.S.)

  7. On symmetric pyramidal finite elements

    Czech Academy of Sciences Publication Activity Database

    Liu, L.; Davies, K. B.; Yuan, K.; Křížek, Michal

    2004-01-01

    Roč. 11, 1-2 (2004), s. 213-227 ISSN 1492-8760 R&D Projects: GA AV ČR IAA1019201 Institutional research plan: CEZ:AV0Z1019905 Keywords : mesh generation * finite element method * composite elements Subject RIV: BA - General Mathematics Impact factor: 0.108, year: 2004

  8. Fluid element in SAP IV

    International Nuclear Information System (INIS)

    Yilmaz, C.; Akkas, N.

    1979-01-01

    In previous studies a fluid element is incorporated in the widely used general purpose finite element program SAPIV. This type of problem is of interest in the design of nuclear components involving geometric complexities and nonlinearities. The elasticity matrix of a general-purpose finite element program is modified in such a way that it becomes possible to idealize fluid as a structural finite element with zero shear modulus and a given bulk modules. Using the modified version of SAPIV, several solid-fluid interactions problems are solved. The numerical solutions are compared with the available analytical solutions. They are shown to be in reasonable aggrement. It is also shown that by solving an exterior-fluid interaction problem, the pressure wave propagation in the acoustic medium can be solved with the same approach. In this study, two of the problem not studied in the previous work will be presented. These problems are namely the effects of the link elements used at solid-fluid interfaces and of the concentrated loads on the response of the fluid medium. Truss elements are used as the link elements. After these investigations, it is decided that general purpose finite element programs with slight modifications can be used in the safety analysis of nuclear reactor plants. By this procedure it is possible to handle two-dimensional plane strain and tridimensional axisymmetric problems of this type. (orig.)

  9. Chemical experiments with superheavy elements.

    Science.gov (United States)

    Türler, Andreas

    2010-01-01

    Unnoticed by many chemists, the Periodic Table of the Elements has been extended significantly in the last couple of years and the 7th period has very recently been completed with eka-Rn (element 118) currently being the heaviest element whose synthesis has been reported. These 'superheavy' elements (also called transactinides with atomic number > or = 104 (Rf)) have been artificially synthesized in fusion reactions at accelerators in minute quantities of a few single atoms. In addition, all isotopes of the transactinide elements are radioactive and decay with rather short half-lives. Nevertheless, it has been possible in some cases to investigate experimentally chemical properties of transactinide elements and even synthesize simple compounds. The experimental investigation of superheavy elements is especially intriguing, since theoretical calculations predict significant deviations from periodic trends due to the influence of strong relativistic effects. In this contribution first experiments with hassium (Hs, atomic number 108), copernicium (Cn, atomic number 112) and element 114 (eka-Pb) are reviewed.

  10. Repetitive elements in parasitic protozoa

    Directory of Open Access Journals (Sweden)

    Clayton Christine

    2010-05-01

    Full Text Available Abstract A recent paper published in BMC Genomics suggests that retrotransposition may be active in the human gut parasite Entamoeba histolytica. This adds to our knowledge of the various types of repetitive elements in parasitic protists and the potential influence of such elements on pathogenicity. See research article http://www.biomedcentral.com/1471-2164/11/321

  11. Finite element analysis of an inflatable torus considering air mass structural element

    Science.gov (United States)

    Gajbhiye, S. C.; Upadhyay, S. H.; Harsha, S. P.

    2014-01-01

    Inflatable structures, also known as gossamer structures, are at high boom in the current space technology due to their low mass and compact size comparing to the traditional spacecraft designing. Internal pressure becomes the major source of strength and rigidity, essentially stiffen the structure. However, inflatable space based membrane structure are at high risk to the vibration disturbance due to their low structural stiffness and material damping. Hence, the vibration modes of the structure should be known to a high degree of accuracy in order to provide better control authority. In the past, most of the studies conducted on the vibration analysis of gossamer structures used inaccurate or approximate theories in modeling the internal pressure. The toroidal shaped structure is one of the important key element in space application, helps to support the reflector in space application. This paper discusses the finite-element analysis of an inflated torus. The eigen-frequencies are obtained via three-dimensional small-strain elasticity theory, based on extremum energy principle. The two finite-element model (model-1 and model-2) have cases have been generated using a commercial finite-element package. The structure model-1 with shell element and model-2 with the combination of the mass of enclosed fluid (air) added to the shell elements have been taken for the study. The model-1 is computed with present analytical approach to understand the convergence rate and the accuracy. The convergence study is made available for the symmetric modes and anti-symmetric modes about the centroidal-axis plane, meeting the eigen-frequencies of an inflatable torus with the circular cross section. The structural model-2 is introduced with air mass element and analyzed its eigen-frequency with different aspect ratio and mode shape response using in-plane and out-plane loading condition are studied.

  12. A new strain based brick element for plate bending

    Directory of Open Access Journals (Sweden)

    L. Belounar

    2014-03-01

    Full Text Available This paper presents the development of a new three-dimensional brick finite element by the use of the strain based approach for the linear analysis of plate bending. The developed element has the three essential external degrees of freedom (U, V and W at each of the eight corner nodes as well as at the centroidal node. The displacement field of the developed element is based on assumed functions for the various strains satisfying the compatibility equations and the static condensation technique is used for the internal node. The performance of this element is evaluated on several problems related to thick and thin plate bending in linear analysis. The obtained results show the good performances and accuracy of the present element.

  13. Free elements resonator: design and simulation, application to NMR imaging

    International Nuclear Information System (INIS)

    Fakri-Bouchet, L.; Lapray, Ch.; Briquet, A.

    1999-01-01

    The free elements resonator, has a bird cage structure. It is made with purely inductively coupled circuits which are individually pre-tuned. The resonance frequency is adjusted by a simultaneous rotation of elements that preserves the coil symmetry. The radiofrequency functioning can be analysis by the usual set of coupled differential equations leading to the resonant modes. In the work presented here the formal analysis is completed by a simulation based on software (Pspice). The characteristics of each element (resistance, self-inductance, capacitance) are Firstly measured, as well as the mutual inductance between each couple of elements. Then the resonant modes and the corresponding current and voltage distribution are obtained to evaluate the radiofrequency field. Using this approach, a free elements bird-cage for efficient operation at 2 Tesla is designed. (authors)

  14. Comparison of 3-D finite elements for incompressible fluid flow

    International Nuclear Information System (INIS)

    Robichaud, M.; Tanguy, P.A.

    1985-01-01

    In recent years, the finite element method applied to the solution of incompressible fluid flow has been in constant evolution. In the present state-of-the-art, 2-D problems are solved routinely and reliable results are obtained at a reasonable cost. In 3-D the finite element method is still undergoing active research and many methods have been proposed to solve the Navier-Stokes equations at 'low cost'. These methods have in common the choice of the element which has a trilinear velocity and a discontinuous constant pressure (Q1-PO). The prohibitive cost of 3-D finite element method in fluid flow is the reason for this choice: the Q1-PO is the simplest and the cheapest 3-D element. However, as mentioned in (5) and (6), it generates 'spurious' pressure modes phenomenon called checkerboarding. On regular mesh these spurious modes can be filtered but on distorted mesh the pressure solution is meaningless. (author)

  15. Predicting the properties of the 113 to 120 transactinide elements

    International Nuclear Information System (INIS)

    Bonchev, D.; Kamenska, V.

    1981-01-01

    The information indices, recently introduced for the description of the electronic structure of atoms, are used as a more convenient basis than atomic number (or period number) for correlations with the properties of the chemical elements within the main groups of the periodic table. When the derived equations are extrapolated, the expected values for a number of properties or characteristics of the 113 to 120 transactinide elements are obtained: entropies in the gas and solid state, heats of melting and sublimation, melting and boiling points, first and second ionization potentials, atomic volumes, densities, covalent radii, and orbital exponents. Some corrections to the predictions were made by proceeding from the similarity in the trend of the expected values for elements 113 to 120 and the known data on elements 81 to 88. Some properties of elements 85 to 88, missing from the literature, were also calculated

  16. VIRTUAL EXPERIMENTAL ANALYSIS ON CLEANING ELEMENT OF SUGARCANE HARVESTER

    Institute of Scientific and Technical Information of China (English)

    Ma Fanglan; Li Shangping; He Yulin; Meng Yanmei; Chen Weixu

    2005-01-01

    The laws of influence of different factors have been analyzed in order to enhance the working efficiency and fatigue life of the cleaning element in brush shape of the sugarcane harvester.Based on the principle of orthogonal experiment design, the virtual-orthogonal-experimental analysis for the cleaning element is carried out on the finite element analysis (FEA) software-ANSYS after analyzing the nonlinear structural behavior in the working procedure. The results are analyzed with the overall balancing method, and then the optimal combination is got, which is made up of different levels of different factors. Also the optimal combination of design parameters of the cleaning element received from the virtual experimental analysis is conducted an experiment to confirm that the virtual analysis model and results are right, and the effect of factors on the function of the cleaning element is obtained by more analysis and further optimizing.

  17. Evaluation of physical-protection elements for interior applications

    International Nuclear Information System (INIS)

    Scott, S.H.

    1983-01-01

    Considerable emphasis has been given in recent years to the threat of sabotage by an insider at nuclear facilities. This threat is inherently different from the outsider threat of theft or sabotage because of the insiders' unique knowledge and access to vital material and equipment. Thus, special safeguards elements are needed in order to counter the insider threat. In addition, insider physical protection system elements must be compatible with the operations, safety, and maintenance programs at the facility. To help identify elements which meet these needs, field evaluations were performed on an interior access control system, piping sensors, interior video motion detectors, and valve monitoring devices. These elements were tested in a realistic operating environment and both technical and operational evaluation data were obtained. Safeguards element descriptions and the results of the operational tests and evaluations are outlined

  18. Trace elements in human milk

    Energy Technology Data Exchange (ETDEWEB)

    Parr, R M [International Atomic Energy Agency, Vienna (Austria). Div. of Life Sciences

    1983-06-01

    Trace elements are those elements having a concentration lower than 10 ppm in body fluids or tissues. A total of 24 elements, both trace and minor elements, present in human milk have been analysed in this study, employing neutron activation analysis and absorption spectroscopy. The analyses have been carried out collaboratively by several different laboratories and the Agency which has also served as a coordinating centre. Although the evaluation of the results, altogether 8500 separate values, is still in progress, enough evidence is already available, however, to show some very interesting differences between different study areas and, in some cases, between different socio-economic groups within a single country. The main value of these data will probably be to throw new light on the nutritional requirements of young babies for trace elements.

  19. Massively Parallel Finite Element Programming

    KAUST Repository

    Heister, Timo

    2010-01-01

    Today\\'s large finite element simulations require parallel algorithms to scale on clusters with thousands or tens of thousands of processor cores. We present data structures and algorithms to take advantage of the power of high performance computers in generic finite element codes. Existing generic finite element libraries often restrict the parallelization to parallel linear algebra routines. This is a limiting factor when solving on more than a few hundreds of cores. We describe routines for distributed storage of all major components coupled with efficient, scalable algorithms. We give an overview of our effort to enable the modern and generic finite element library deal.II to take advantage of the power of large clusters. In particular, we describe the construction of a distributed mesh and develop algorithms to fully parallelize the finite element calculation. Numerical results demonstrate good scalability. © 2010 Springer-Verlag.

  20. Massively Parallel Finite Element Programming

    KAUST Repository

    Heister, Timo; Kronbichler, Martin; Bangerth, Wolfgang

    2010-01-01

    Today's large finite element simulations require parallel algorithms to scale on clusters with thousands or tens of thousands of processor cores. We present data structures and algorithms to take advantage of the power of high performance computers in generic finite element codes. Existing generic finite element libraries often restrict the parallelization to parallel linear algebra routines. This is a limiting factor when solving on more than a few hundreds of cores. We describe routines for distributed storage of all major components coupled with efficient, scalable algorithms. We give an overview of our effort to enable the modern and generic finite element library deal.II to take advantage of the power of large clusters. In particular, we describe the construction of a distributed mesh and develop algorithms to fully parallelize the finite element calculation. Numerical results demonstrate good scalability. © 2010 Springer-Verlag.

  1. Trace element impurity determination in aspirin tablets by INAA

    International Nuclear Information System (INIS)

    Miyoshi, E.K.; Saiki, M.

    2009-01-01

    Instrumental neutron activation analysis (INAA) was applied to assess trace element concentrations in six samples of aspirin tablets acquired in Sao Paulo city, Brazil. Concentrations of the elements Br, Ca, Co, Cr, Fe, K, La, Na, Sc and Zn were determined. Comparisons were made between the results obtained with published data for aspirins from foreign countries. Certified reference materials, INCT-MPH-2 Mixed Polish Herbs were analyzed for quality control of the analytical results. (author)

  2. Determination of plutoniumn and transplutonium elements in the environment

    International Nuclear Information System (INIS)

    Willemot, J.M.; Verry, M.; Jeanmaire, L.

    1988-01-01

    Environmental samples made of many different stable elements and natural emitting radionuclides must undergo chemical analysis allowing to prepare quality sources. Plutonium and americium sources with a good resolution can be obtained from environmental samples by successive operations of co-precipitation ion-exchange separation and solvent extraction. Spectral analysis is then simple and consequently plutonium and transplutonium elements are determined easily in such samples. 15 refs [fr

  3. Method for fuel element leak detection in pressurized water reactors

    International Nuclear Information System (INIS)

    Kunze, U.

    1983-01-01

    The method is aimed at detecting fuel element leaks during reactor operation. It is based on neutron flux measurements at many points in the core, using at least two detectors at a time. The detectors must be arranged in the direction of the coolant flow. Values obtained from periodic measurements are compared with threshold values. The location of fuel element leaks is determined from those values exceeding the threshold of individual detectors

  4. On peculiarities of distribution of some elements in vegetation samples

    International Nuclear Information System (INIS)

    Bakiev, S.A.; Rakhmanov, J.; Khakimov, Z.M.; Turayev, S.

    2005-01-01

    This work is devoted to the neutron-activation analysis of medicines of vegetation origin and some herbs, vegetables, fruits and cereals, which are used in oriental medicine, in order to reveal peculiarities of distribution of studied elements in them and possible relations between this distribution and parameters of oriental medicine. The sampling involving 85 species and their preparation for analysis, as well as complex of necessary methodological studies were performed and the method of sample analysis for 14 macro- and microelements (Na, Al, Cl, K, Sc, Mn, Fe, Co, Cu, Zn, Br, J, La, Au) was developed. The studies carried out have enabled one to obtain data on concentrations of these elements and to reveal peculiarities of their distribution in the samples under interest. It was revealed herbs, fruits and cereals with pronounced higher concentrations (with respect to the mean values) of one or another element, which are perhaps concentrators of those elements, as well as samples with lower concentrations of elements (see table). It is indicative that in all herbs only enhanced concentrations of elements are observed, but in fruits and cereals-only lowered concentrations of elements. These results can be of interest for geochemical ecology, dietology, therapy, as well as for activities on correction of elemental content of ecosystems, including soils, and alive organisms It is suggested to continue studies with extension of range of object types and analysed elements. Mathematical analysis of the obtained results was performed with comparison of concentrations of a number of elements in the different objects with classifying parameters ('cold-hot' and 'dry-wet') of these objects according to oriental medicine. In the current stage of studies no relation between these parameters and concentrations has been found. It does not mean that there are not such relations at all, they may be revealed with extension and development of our' studies.

  5. An Explicit Consistent Geometric Stiffness Matrix for the DKT Element

    Directory of Open Access Journals (Sweden)

    Eliseu Lucena Neto

    Full Text Available Abstract A large number of references dealing with the geometric stiffness matrix of the DKT finite element exist in the literature, where nearly all of them adopt an inconsistent form. While such a matrix may be part of the element to treat nonlinear problems in general, it is of crucial importance for linearized buckling analysis. The present work seems to be the first to obtain an explicit expression for this matrix in a consistent way. Numerical results on linear buckling of plates assess the element performance either with the proposed explicit consistent matrix, or with the most commonly used inconsistent matrix.

  6. LOAD BEARING CAPACITY OF THE GLASS RAILING ELEMENT

    Directory of Open Access Journals (Sweden)

    Elizabeta Šamec

    2016-02-01

    Full Text Available In this paper some basic physical and mechanical properties of glass as structural material are presented. This research is about specifically manufactured glass railing element that will be a part of a pedestrian bridge construction in Zagreb, Croatia. Load bearing capacity test of the glass railing element is conducted within the Faculty of Civil Engineering in Zagreb and obtained experimental results are discussed and compared to the ones provided by the numerical model. Taking into account the behaviour of laminated glass and results of experimental and numerical testing, glass railing element can be regarded as safe.

  7. Selectable six-element multicoil array for entire spine imaging

    International Nuclear Information System (INIS)

    Byrne, J.W.; Bluma-Walter, J.; Prorok, R.J.

    1990-01-01

    This article introduces a new multicoil array that can provide entire spine imaging in two acquisitions with no need to manually reposition either the coil or the patient. A selectable contoured multicoil array with six elements was used to obtain coverage of the entire spine. The first four elements were used for imaging the upper spine region (cervical/thoracic) during the first acquisition, and the last four elements were used for imaging the lower spine region (thoracic/lumbar) during the second acquisition. The overall coil length was approximately 75 cm

  8. Review of Tomographic Imaging using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Mohd Fua’ad RAHMAT

    2011-12-01

    Full Text Available Many types of techniques for process tomography were proposed and developed during the past 20 years. This paper review the techniques and the current state of knowledge and experience on the subject, aimed at highlighting the problems associated with the non finite element methods, such as the ill posed, ill conditioned which relates to the accuracy and sensitivity of measurements. In this paper, considerations for choice of sensors and its applications were outlined and descriptions of non finite element tomography systems were presented. The finite element method tomography system as obtained from recent works, suitable for process control and measurement were also presented.

  9. Test on large-scale seismic isolation elements, 2

    International Nuclear Information System (INIS)

    Mazda, T.; Moteki, M.; Ishida, K.; Shiojiri, H.; Fujita, T.

    1991-01-01

    Seismic isolation test program of Central Research Inst. of Electric Power Industry (CRIEPI) to apply seismic isolation to Fast Breeder Reactor (FBR) plant was started in 1987. In this test program, demonstration test of seismic isolation elements was considered as one of the most important research items. Facilities for testing seismic isolation elements were built in Abiko Research Laboratory of CRIEPI. Various tests of large-scale seismic isolation elements were conducted up to this day. Many important test data to develop design technical guidelines was obtained. (author)

  10. Advanced solid elements for sheet metal forming simulation

    Science.gov (United States)

    Mataix, Vicente; Rossi, Riccardo; Oñate, Eugenio; Flores, Fernando G.

    2016-08-01

    The solid-shells are an attractive kind of element for the simulation of forming processes, due to the fact that any kind of generic 3D constitutive law can be employed without any additional hypothesis. The present work consists in the improvement of a triangular prism solid-shell originally developed by Flores[2, 3]. The solid-shell can be used in the analysis of thin/thick shell, undergoing large deformations. The element is formulated in total Lagrangian formulation, and employs the neighbour (adjacent) elements to perform a local patch to enrich the displacement field. In the original formulation a modified right Cauchy-Green deformation tensor (C) is obtained; in the present work a modified deformation gradient (F) is obtained, which allows to generalise the methodology and allows to employ the Pull-Back and Push-Forwards operations. The element is based in three modifications: (a) a classical assumed strain approach for transverse shear strains (b) an assumed strain approach for the in-plane components using information from neighbour elements and (c) an averaging of the volumetric strain over the element. The objective is to use this type of elements for the simulation of shells avoiding transverse shear locking, improving the membrane behaviour of the in-plane triangle and to handle quasi-incompressible materials or materials with isochoric plastic flow.

  11. Simulation Analysis of Tilted Polyhedron-Shaped Thermoelectric Elements

    Science.gov (United States)

    Meng, Xiangning; Suzuki, Ryosuke O.

    2015-06-01

    The generation of thermoelectricity is considered a promising approach to harness the waste heat generated in industries, automobiles, gas fields, and other man-made processes. The waste heat can be converted to electricity via a thermoelectric (TE) generator. In this light, the generator performance depends on the geometric configuration of its constituent elements as well as their material properties. Our previous work reported TE behaviors for modules consisting of parallelogram-shaped elements, because elements with tilted laminate structures provide increased mechanical stability and efficient heat-transferring ability from the hot surface to the cold surface. Here, we study TE elements in the shape of a polyhedron that is obtained by mechanically truncating the edges of a parallelogram element in order to further enhance the generator performance and reduce TE material usage. The TE performance of the modules consisting of these polyhedron elements is numerically simulated by using the finite-volume method. The output power, voltage, and current of the polyhedral TE module are greater than those of the parallelogram-element module. The polyhedron shape positively affects heat transfer and the flow of electric charges in the light of increasing the efficiency of conversion from heat to electricity. By varying the shape of the truncated portions, we determine the optimal shape that enables homogeneous heat flux distribution and slow diffusion of thermal energy to obtain the better efficiency of conversion of heat into electricity. We believe that the findings of our study can significantly contribute to the design policy in TE generation.

  12. Automatic inspection for remotely manufactured fuel elements

    International Nuclear Information System (INIS)

    Reifman, J.; Vitela, J.E.; Gibbs, K.S.; Benedict, R.W.

    1995-01-01

    Two classification techniques, standard control charts and artificial neural networks, are studied as a means for automating the visual inspection of the welding of end plugs onto the top of remotely manufactured reprocessed nuclear fuel element jackets. Classificatory data are obtained through measurements performed on pre- and post-weld images captured with a remote camera and processed by an off-the-shelf vision system. The two classification methods are applied in the classification of 167 dummy stainless steel (HT9) fuel jackets yielding comparable results

  13. Interdependence of different symmetry energy elements

    Science.gov (United States)

    Mondal, C.; Agrawal, B. K.; De, J. N.; Samaddar, S. K.; Centelles, M.; Viñas, X.

    2017-08-01

    Relations between the nuclear symmetry energy coefficient and its density derivatives are derived. The relations hold for a class of interactions with quadratic momentum dependence and a power-law density dependence. The structural connection between the different symmetry energy elements as obtained seems to be followed by almost all reasonable nuclear energy density functionals, both relativistic and nonrelativistic, suggesting a universality in the correlation structure. This, coupled with known values of some well-accepted constants related to nuclear matter, helps in constraining values of different density derivatives of the nuclear symmetry energy, shedding light on the isovector part of the nuclear interaction.

  14. Element depth profiles of porous silicon

    International Nuclear Information System (INIS)

    Kobzev, A.P.; Nikonov, O.A.; Kulik, M.; Zuk, J.; Krzyzanowska, H.; Ochalski, T.J.

    1997-01-01

    Element depth profiles of porous silicon were measured on the Van-de-Graaff accelerator in the energy range of 4 He + ions from 2 to 3.2 MeV. Application of complementary RBS, ERD and 16 O(α,α) 16 O nuclear reaction methods permits us to obtain: 1) the exact silicon, oxygen and hydrogen distribution in the samples, 2) the distribution of partial pore concentrations. The oxygen concentration in porous silicon reaches 30%, which allows one to assume the presence of silicon oxide in the pores and to explain the spectrum shift of luminescence into the blue area

  15. SEM and elemental analysis of composite resins

    International Nuclear Information System (INIS)

    Hosoda, H.; Yamada, T.; Inokoshi, S.

    1990-01-01

    Twenty-four chemically cured, 21 light-cured anterior, three light-cured anterior/posterior, and 18 light-cured posterior composite resins were examined using scanning electron microscopy, and the elemental composition of their filler particles was analyzed with an energy dispersive electron probe microanalyzer. According to the results obtained, the composite resins were divided into five groups (traditional, microfilled type, submicrofilled type, hybrid type, and semihybrid), with two additional hypothetical categories (microfilled and hybrid). Characteristics of each type were described with clinical indications for selective guidance of respective composite resins for clinical use

  16. 48 CFR 1815.403 - Obtaining cost or pricing data.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Obtaining cost or pricing... ADMINISTRATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing 1815.403 Obtaining cost or pricing data. ...

  17. Hydrogen in CANDU fuel elements

    International Nuclear Information System (INIS)

    Sejnoha, R.; Manzer, A.M.; Surette, B.A.

    1995-01-01

    Unirradiated and irradiated CANDU fuel cladding was tested to compare the role of stress-corrosion cracking and of hydrogen in the development of fuel defects. The results of the tests are compared with information on fuel performance in-reactor. The role of hydriding (deuteriding) from the coolant and from the fuel element inside is discussed, and the control of 'hydrogen gas' content in the element is confirmed as essential for defect-free fuel performance. Finally, implications for fuel element design are discussed. (author)

  18. Origin of the chemical elements

    Energy Technology Data Exchange (ETDEWEB)

    Tayler, R J

    1984-05-01

    The subject is discussed in relation to the composition of initially created matter and changes which have occurred during the life history of the universe, with particular reference to our galaxy and nearby galaxies. Headings are: observations of element abundances (stars, gas clouds in our own and nearby galaxies, hot gas in galaxy clusters, the solar system); the originally created matter (Big Bang theory and early nuclear reactions); processes changing observed composition (galactic evolution; nuclear fusion reactions in stellar interiors; chemical composition of a highly evolved massive star); supernovae (production of heavy elements); chemical evolution of the galaxy; production of very heavy elements (s process, r process).

  19. Increased burnup of fuel elements

    International Nuclear Information System (INIS)

    Ahlf, J.

    1983-01-01

    The specialists' group for fuel elements of the Kerntechnische Gesellschaft e.V. held a meeting on ''Increased Burnup of Fuel Elements'' on 9th and 10th of November 1982 at the GKSS Research Center Geesthacht. Most papers dealt with the problems of burnup increase of fuel elements for light water reactors with respect to fuel manufacturing, power plant operation and reprocessing. Review papers were given on the burnup limits for high temperature gas cooled reactors and sodium fast breeder reactors. The meeting ended with a presentation of the technical equipment of the hot laboratory of the GKSS and the programs which are in progress there. (orig.) [de

  20. Infrared Fourier spectres of pectin obtained from pumpkin

    International Nuclear Information System (INIS)

    Usmanova, S.R.; Dzhonmurodov, A.S.; Nazirova, Kh.I.; Mukhidinov, Z.K.

    2015-01-01

    Present article is devoted to infrared Fourier spectres of pectin obtained from pumpkin. The analysis of pectin obtained from pumpkin was conducted by means of infrared spectrophotometer with Fourier transformation. The infrared spectroscopic study of pectin polysaccharide fraction of pectin matter, as well as pectin helium and micro helium obtained by means of fast extraction was conducted.

  1. 32 CFR 806b.8 - Obtaining law enforcement records.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Obtaining law enforcement records. 806b.8 Section 806b.8 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE ADMINISTRATION PRIVACY ACT PROGRAM Obtaining Law Enforcement Records and Confidentiality Promises § 806b.8 Obtaining law enforcement records. The Commander, Air...

  2. 15 CFR 748.2 - Obtaining forms; mailing addresses.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Obtaining forms; mailing addresses... APPLICATIONS (CLASSIFICATION, ADVISORY, AND LICENSE) AND DOCUMENTATION § 748.2 Obtaining forms; mailing addresses. (a) You may obtain the forms required by the EAR from any U.S. Department of Commerce District...

  3. ELECTROCHEMICAL TECHNOLOGIES FOR OBTAINING MOULDS FOR SOLES OF SHOES

    Directory of Open Access Journals (Sweden)

    Cornelia LUCA

    2013-05-01

    Full Text Available The paper presents contributions in the designing of some electrochemical technologiesfor the manufacturing of the moulds used in the footwear soles obtaining. There are presented a fewmethods for the moulds obtaining, using electro-deposit processes. There are presented thetechnological phases of the obtaining process of the electrolytes and electrodes preparing and thetechnological stages of the moulds manufacturing.

  4. Prioritising Project Scope Definition Elements in Public Building Projects

    Directory of Open Access Journals (Sweden)

    Mohammed K Fageha

    2014-09-01

    Full Text Available A complete definition of the scope of a project upfront during early stages ensures smooth and successful implementation during the project execution. This research identifies and prioritises project scope definition elements for public buildings in Saudi Arabia. Elements that could significantly contribute to complete project scope definition package at pre-project planning stage are identified and their interrelationship determined and prioritised. Using the Project Definition Rating Index (PDRI as a basis, the study uses analytical network process (ANP technique based on data obtained from project managers who have been involved in public sector projects in Saudi Arabia. Data collection and analysis was conducted in three steps. The first step involved identification of scope definition elements while the second involved an investigation into interrelationships among the elements. In the third step, ANP was used to determine the weight of the elements’ importance in terms of contribution to project scope definition completeness. Finally, Pareto analysis was used to prioritise and assess the distribution pattern of the elements. The outcome from this research is the prioritisation of project scope definition elements for public building projects in Saudi Arabia. The prioritised list developed indicates the importance of project scope definition elements. It should help project management teams identify elements to consider when evaluating project scope definition for completeness at the pre-project planning stage. Keywords: Project scope definition, pre-project planning, prioritising, public building projects, Saudi Arabia, Analytical Network Process (ANP

  5. Improved combination of photosensitivity elements for use in radiography

    International Nuclear Information System (INIS)

    Doorselaer, M.K.

    1975-01-01

    It is stated that manufacturers of photosensitive elements incorporating silver halide emulsions for use in radiography are often faced with performance requirements that place conflicting demands on the composition of the photosensitive elements. Amongst such performance requirements are a minimum photographic speed, a short processing time, and a minimum standard of image density and resolution. With a view to achieving some degree of reconciliation between maximum optical image density requirements and economy in processing time, and in particular fixing time, it is advantageous to have the total silver halide content distributed in emulsion layers on opposite sides of the emulsion layer support. Such 'double sided' elements are usually exposed between two intensifying screens, that may be separate elements of integral parts of a single element that also incorporates the silver halide emulsion layers. During exposure of these 'double sided' elements light from one intensifying screen irradiates the adjacent emulsion layer and also that on the opposite side of the support; this is referred to as 'cross over'. Due to refraction and other light deflection processes within the photosensitive element this, however, impairs image definition. In commercial systems a relatively high concentration of siver halide is usually employed in order to obtain good contrast and maximum image density, but this adversely affects processing time. Instead of such high silver halide concentrations emulsions of small silver halide grain size may be used, but this lowers the photographic speed. Elements having properties that mitigate these difficulties are described, and examples of their application are given. (U.K.)

  6. Multi-element analyses of earthworms for radioecology and ecotoxicology

    International Nuclear Information System (INIS)

    Yoshida, S.; Peijnenburg, W.; Muramatsu, Y.

    2004-01-01

    Increasing concern about environmental radiation protection has raised awareness that more information is required on the transfer and accumulation of radionuclides in the biological compartments of ecosystems. ICRP (International Commission on Radiological Protection) selected earthworm as one of the reference organisms in their radiation protection recommendations. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. In addition, a change of the elemental composition itself might be a possible indicator of the effect on the earthworm and/or ecosystem. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for more than 30 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors of the elements were determined both for laboratory and natural conditions. The controlling factors on the transfer parameters such as the bioavailability of the elements in the soils will also be discussed. (author)

  7. Lasers with intra-cavity phase elements

    Science.gov (United States)

    Gulses, A. Alkan; Kurtz, Russell; Islas, Gabriel; Anisimov, Igor

    2018-02-01

    Conventional laser resonators yield multimodal output, especially at high powers and short cavity lengths. Since highorder modes exhibit large divergence, it is desirable to suppress them to improve laser quality. Traditionally, such modal discriminations can be achieved by simple apertures that provide absorptive loss for large diameter modes, while allowing the lower orders, such as the fundamental Gaussian, to pass through. However, modal discrimination may not be sufficient for short-cavity lasers, resulting in multimodal operation as well as power loss and overheating in the absorptive part of the aperture. In research to improve laser mode control with minimal energy loss, systematic experiments have been executed using phase-only elements. These were composed of an intra-cavity step function and a diffractive out-coupler made of a computer-generated hologram. The platform was a 15-cm long solid-state laser that employs a neodymium-doped yttrium orthovanadate crystal rod, producing 1064 nm multimodal laser output. The intra-cavity phase elements (PEs) were shown to be highly effective in obtaining beams with reduced M-squared values and increased output powers, yielding improved values of radiance. The utilization of more sophisticated diffractive elements is promising for more difficult laser systems.

  8. Laser assisted decontamination of nuclear fuel elements

    International Nuclear Information System (INIS)

    Padma Nilaya, J.; Biswas, Dhruba J.; Kumar, Aniruddha

    2010-04-01

    Laser assisted removal of loosely bound fuel particulates from the clad surface following the process of pellet loading has decided advantages over conventional methods. It is a dry and noncontact process that generates very little secondary waste and can occur inside a glove box without any manual interference minimizing the possibility of exposure to personnel. The rapid rise of the substrate/ particulate temperature owing to the absorption of energy from the incident laser pulse results in a variety of processes that may lead to the expulsion of the particulates. As a precursor to the cleaning of the fuel elements, initial experiments were carried out on contamination simulated on commonly used clad surfaces to gain a first hand experience on the various laser parameters for which as efficient cleaning can be obtained without altering the properties of the clad surface. The cleaning of a dummy fuel element was subsequently achieved in the laboratory by integrating the laser with a work station that imparted simultaneous rotational and linear motion to the fuel element. (author)

  9. The Role of Trace Elements in Tinnitus.

    Science.gov (United States)

    Yaşar, Mehmet; Şahin, Mehmet İlhan; Karakükçü, Çiğdem; Güneri, Erhan; Doğan, Murat; Sağıt, Mustafa

    2017-03-01

    In this study, we aimed to investigate the role of three trace elements, namely, zinc, copper, and lead, in tinnitus by analyzing the serum level of copper and lead and both the serum and tissue level of zinc. Eighty patients, who applied to outpatient otolaryngology clinic with the complaints of having tinnitus, and 28 healthy volunteers were included. High-frequency audiometry was performed, and participants who had hearing loss according to the pure tone average were excluded; tinnitus frequency and loudness were determined and tinnitus reaction questionnaire scores were obtained from the patients. Of all the participants, serum zinc, copper, and lead values were measured; moreover, zinc levels were examined in hair samples. The levels of trace elements were compared between tinnitus and control groups. The level of copper was found to be significantly lower in the tinnitus group (p = 0.02), but there was no significant difference between the groups in terms of the levels of zinc, neither in serum nor in hair, and lead in serum (p > 0.05). The lack of trace elements, especially that of "zinc," have been doubted for the etiopathogenesis of tinnitus in the literature; however, we only found copper levels to be low in patients having tinnitus.

  10. The effect of uncertainty of reactor parameters obtained using k0-NAA on result of analysis

    International Nuclear Information System (INIS)

    Sasajima, Fumio

    2006-01-01

    Neutron Activation Analysis using the k 0 method is a useful method allowing convenient and accurate simultaneous analysis of plural elements, eliminating the need for the use of comparative reference samples. As already well known, it is essential for the correct result of an analysis to obtain the α-factor and f-factor for a neutron spectrum in an irradiation field accurately when an attempt is made to use the k 0 method. For this reason, based on data obtained from the experiment conducted in the JRR-3 PN-3 system, how uncertainty of the measured values for α-factor and f-factor affects the result of an analysis was evaluated. The process of evaluation involved intentionally varying the values for reactor parameters followed by making an analysis of environmental reference samples (NIST SRM-1632c) using the k 0 method to examine the effect of these factors on the concentrations of 19 elements. The result of the evaluation revealed that the degree of the effect of uncertainty on the concentrations of 19 elements was at best approx. 1% under the condition of this experiment assuming that the factor α, a reactor parameter, had uncertainty of approx. 200%. (author)

  11. Plasma Methods of Obtainment of Multifunctional Composite Materials, Dispersion-Hardened by Nanoparticles

    Science.gov (United States)

    Sizonenko, O. N.; Grigoryev, E. G.; Pristash, N. S.; Zaichenko, A. D.; Torpakov, A. S.; Lypian, Ye. V.; Tregub, V. A.; Zholnin, A. G.; Yudin, A. V.; Kovalenko, A. A.

    2017-09-01

    High voltage electric discharge (HVED) in disperse system "hydrocarbon liquid - powder" due to impact of plasma discharge channel, electromagnetic fields, shock waves mechanical impact, hydro flows and volume microcavitation leads to synthesis of nanocarbon, metal powders dispersion and synthesis of micro- (from 10-6 to 10-7 m) and nanosized (from 10-7 to 10-9 m) composite powders of hardening phases. Spark plasma sintering (SPS) of powder mixtures allows targeted control of grain growth rate and thus allows obtainment of multifunctional composite materials dispersion hardened by nanoparticles. Processes of HVED synthesis of micro- and nanosized powders of new compositions from elemental metal powders and their mixtures with the subsequent application of high-speed SPS of obtained powders create conditions for increase of strength (by 10-20 %), hardness and wear-resistance (by 30-60 %) of obtained materials.

  12. A new approach to obtaining the roots of the dispersion equation for slab geometry multiplying media

    International Nuclear Information System (INIS)

    Silva, Davi J.M.; Barros, Ricardo C.; Alves Filho, Hermes

    2013-01-01

    In this work we describe an alternative approach for obtaining the roots of the dispersion equation. For the mathematical model, we used the slab-geometry neutron transport equation in the discrete ordinates (S N ), formulation, considering isotropic scattering and monoenergetic model. The basic idea is to find a basis for the kernel of the S N differential operator, whose elements are exponential eigenfunctions corresponding to distinct eigenvalues which are the roots of the dispersion equation. That strategy yields a gain in programming computational codes, including the strategy used to obtain the purely imaginary eigenvalues and their associated complex eigenfunctions, that appear in the spectral analysis of the S N equations in multiplying media. These eigenvalues and corresponding eigenfunctions are used to obtain the parameters of the auxiliary equations of the spectral nodal methods, e.g., the spectral diamond (SD) auxiliary equation. (author)

  13. Elements of Tiny Plasma Spectrometers

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to advance major elements of a miniaturized plasma spectrometer for flight on future missions. This type of instrument has been developed and successfully...

  14. Finite element computational fluid mechanics

    International Nuclear Information System (INIS)

    Baker, A.J.

    1983-01-01

    This book analyzes finite element theory as applied to computational fluid mechanics. It includes a chapter on using the heat conduction equation to expose the essence of finite element theory, including higher-order accuracy and convergence in a common knowledge framework. Another chapter generalizes the algorithm to extend application to the nonlinearity of the Navier-Stokes equations. Other chapters are concerned with the analysis of a specific fluids mechanics problem class, including theory and applications. Some of the topics covered include finite element theory for linear mechanics; potential flow; weighted residuals/galerkin finite element theory; inviscid and convection dominated flows; boundary layers; parabolic three-dimensional flows; and viscous and rotational flows

  15. Nuclear reactor fuel element assemblies

    International Nuclear Information System (INIS)

    Krawiec, D.M.; Bevilacqua, F.

    1974-01-01

    The fuel elements of each fuel element group are separated from each other by means of a multitude of thin, intersecting plates in the from of grid strips. Flow deflectors near the surface of the fuel elements are used in order to make the coolant flow more turbulent. They are designed as vanes and arranged at a distance on the grid strips. Each deflector vane has two arms stretching in opposite directions, each one into a neighbouring channel. In outward direction, the deflector vanes are converging. The strips with the vanes can be put on the supporting grid of the fuel elements. The vane structure can be reinforced by providing distortions in the strip material near the vanes. (DG) [de

  16. Elemental ABAREX -- a user's manual

    International Nuclear Information System (INIS)

    Smith, A.B.

    1999-01-01

    ELEMENTAL ABAREX is an extended version of the spherical optical-statistical model code ABAREX, designed for the interpretation of neutron interactions with elemental targets consisting of up to ten isotopes. The contributions from each of the isotopes of the element are explicitly dealt with, and combined for comparison with the elemental observables. Calculations and statistical fitting of experimental data are considered. The code is written in FORTRAN-77 and arranged for use on the IBM-compatible personal computer (PC), but it should operate effectively on a number of other systems, particularly VAX/VMS and IBM work stations. Effort is taken to make the code user friendly. With this document a reasonably skilled individual should become fluent with the use of the code in a brief period of time

  17. The evolution of the elements

    International Nuclear Information System (INIS)

    Williams, P.M.

    1978-01-01

    It is believed that only the lightest elements, hydrogen and helium, were created during the 'Big Bang' origin of the Universe and that all heavier elements were synthesized by nuclear reactions in stars, the interstellar medium and possibly in 'little bangs' in the nuclei of galaxies. The composition of the interstellar medium has evolved through enrichment by processed material shed by evolving stars and the composition of the Solar System reflects that of the interstellar medium at the time of its formation. Differentiation processes during the evolution of the Solar System and individual planets account for the different compositions of the Sun and the planets. The measurement of the abundance distribution of the elements has become a very powerful tool in the elucidation of the evolution of the Solar System, stars and the Galaxy. This review attempts to trace the formation of the elements in stars and their subsequent evolution. (author)

  18. Environmental research on actinide elements

    International Nuclear Information System (INIS)

    Pinder, J.E. III; Alberts, J.J.; McLeod, K.W.; Schreckhise, R.G.

    1987-08-01

    The papers synthesize the results of research sponsored by DOE's Office of Health and Environmental Research on the behavior of transuranic and actinide elements in the environment. Separate abstracts have been prepared for the 21 individual papers

  19. Electromagnetic matrix elements in baryons

    International Nuclear Information System (INIS)

    Lipkin, H.J.; Moinester, M.A.

    1992-01-01

    Some simple symmetry relations between matrix elements of electromagnetic operators are investigated. The implications are discussed for experiments to study hyperon radiative transitions and polarizabilities and form factors. (orig.)

  20. Programming the finite element method

    CERN Document Server

    Smith, I M; Margetts, L

    2013-01-01

    Many students, engineers, scientists and researchers have benefited from the practical, programming-oriented style of the previous editions of Programming the Finite Element Method, learning how to develop computer programs to solve specific engineering problems using the finite element method. This new fifth edition offers timely revisions that include programs and subroutine libraries fully updated to Fortran 2003, which are freely available online, and provides updated material on advances in parallel computing, thermal stress analysis, plasticity return algorithms, convection boundary c

  1. Pipeline robots with elastic elements

    Directory of Open Access Journals (Sweden)

    A. Matuliauskas

    2002-10-01

    Full Text Available In the article constructions of the pipeline robots with elastic elements are reviewed and the scheme of new original construction is presented. The mathematical models of a robot with one-dimensional vibration exciter with two degrees of freedom were developed and the equations of movement were formed and written. The mathematical model of the pipeline robot with circular elements is formed and its motion equations are presented.

  2. ELEMENTS OF SAFETY IN PARAGLIDING

    OpenAIRE

    Janez Mekinc; Katarina Mušič

    2016-01-01

    Paragliding is an opportunity for tourism development, depending on what position the sport has place in the local community, the restrictions for paragliders and the safety components of the region. The paper explores the phenomenon of paragliding and safety elements in the Upper Soča region, one of ten best paragliding sites in the world (Placestoseeinyourlifetime, 2015). The purpose of the research is to analyse the safety elements, the development and the risk of paragliding.The goals of ...

  3. Fuel element box inspection device

    International Nuclear Information System (INIS)

    Ortmayer, R.M.; Pick, W.

    1985-01-01

    The invention concerns a device for inspecting the outer geometry of a long fuel element box by measuring the surface contours over its longitudinal crossection and along its length by sensors. These are kept in a sledge which can be moved along the fuel element guide in a slot guide. The measurement signals reach an evaluation device outside the longitudinal box. (orig./HP) [de

  4. Nuclear fuel elements and assemblies

    International Nuclear Information System (INIS)

    Saito, Shozo; Maki, Hideo.

    1982-01-01

    Purpose: To facilitate the attainment of the uranium enrichment or gadolinia enrichment of a pellet filled in a fuel element. Constitution: The axial length of a pellet filled in a fuel element is set to predetermined sizes according to the uranium enrichment factor, gadolinia enrichment or their combination. Thus, the uranium enrichment factor or gadolinia enrichment can be identified by attaining the axial length of the pellet by using such a pellt. (Kamimura, M.)

  5. Nuclear reactor fuel element splitter

    International Nuclear Information System (INIS)

    Yeo, D.

    1976-01-01

    A method and apparatus are disclosed for removing nuclear fuel from a clad fuel element. The fuel element is power driven past laser beams which simultaneously cut the cladding lengthwise into at least two longitudinal pieces. The axially cut lengths of cladding are then separated, causing the nuclear fuel contained therein to drop into a receptacle for later disposition. The cut lengths of cladding comprise nuclear waste which is disposed of in a suitable manner. 6 claims, 10 drawing figures

  6. Phase diagrams of the elements

    International Nuclear Information System (INIS)

    Young, D.A.

    1975-01-01

    A summary of the pressure-temperature phase diagrams of the elements is presented, with graphs of the experimentally determined solid-solid phase boundaries and melting curves. Comments, including theoretical discussion, are provided for each diagram. The crystal structure of each solid phase is identified and discussed. This work is aimed at encouraging further experimental and theoretical research on phase transitions in the elements

  7. Nuclear chemistry of transactinide elements

    Energy Technology Data Exchange (ETDEWEB)

    Nagame, Yuichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    The current status on the nuclear chemistry studies of transactinide elements is reviewed. The production of transactinides in heavy ion reactions is briefly discussed, and nuclear properties on the stability of transactinides are presented. Chemical properties of the trans-actinide elements 104, 105 and 106, and a typical experimental technique used to study these properties on an atom-at-a-time base are introduced. (author)

  8. New formulation of the discrete element method

    Science.gov (United States)

    Rojek, Jerzy; Zubelewicz, Aleksander; Madan, Nikhil; Nosewicz, Szymon

    2018-01-01

    A new original formulation of the discrete element method based on the soft contact approach is presented in this work. The standard DEM has heen enhanced by the introduction of the additional (global) deformation mode caused by the stresses in the particles induced by the contact forces. Uniform stresses and strains are assumed for each particle. The stresses are calculated from the contact forces. The strains are obtained using an inverse constitutive relationship. The strains allow us to obtain deformed particle shapes. The deformed shapes (ellipses) are taken into account in contact detection and evaluation of the contact forces. A simple example of a uniaxial compression of a rectangular specimen, discreti.zed with equal sized particles is simulated to verify the DDEM algorithm. The numerical example shows that a particle deformation changes the particle interaction and the distribution of forces in the discrete element assembly. A quantitative study of micro-macro elastic properties proves the enhanced capabilities of the DDEM as compared to standard DEM.

  9. Glass ceramic obtained by tailings and tin mine waste reprocessing from Llallagua, Bolivia

    Science.gov (United States)

    Arancibia, Jony Roger Hans; Villarino, Cecilia; Alfonso, Pura; Garcia-Valles, Maite; Martinez, Salvador; Parcerisa, David

    2014-05-01

    In Bolivia Sn mining activity produces large tailings of SiO2-rich residues. These tailings contain potentially toxic elements that can be removed into the surface water and produce a high environmental pollution. This study determines the thermal behaviour and the viability of the manufacture of glass-ceramics from glass. The glass has been obtained from raw materials representative of the Sn mining activities from Llallagua (Bolivia). Temperatures of maximum nucleation rate (Tn) and crystallization (Tcr) were calculated from the differential thermal analyses. The final mineral phases were determined by X-ray diffraction and textures were observed by scanning electron microscopy. Crystalline phases are nefeline occurring with wollastonite or plagioclase. Tn for nepheline is between 680 ºC and 700 ºC, for wollastonite, 730 ºC and for plagioclase, 740 ºC. Tcr for nefeline is between 837 and 965 ºC; for wollastonite, 807 ºC and for plagioclase, 977 ºC. In order to establish the mechanical characteristics and efficiency of the vitrification process in the fixation of potentially toxic elements the resistance to leaching and micro-hardness were determined. The obtained contents of the elements leached from the glass ceramic are well below the limits established by the European legislation. So, these analyses confirm that potentially toxic elements remain fixed in the structure of mineral phases formed in the glass-ceramic process. Regarding the values of micro-hardness results show that they are above those of a commercial glass. The manufacture of glass-ceramics from mining waste reduces the volume of tailings produced for the mining industry and, in turn enhances the waste, transforming it into a product with industrial application. Acknowledgements: This work was partly financed by the project AECID: A3/042750/11, and the SGR 2009SGR-00444.

  10. New elements - approaching Z=114

    International Nuclear Information System (INIS)

    Hofmann, S.

    1998-03-01

    The search for new elements is part of the broader field of investigations of nuclei at the limits of stability. In two series of experiments at SHIP, six new elements (Z=107-112) were synthesized via fusion reactions using 1n-deexcitation channels and lead or bismuth targets. The isotopes were unambiguously identified by means of α-α correlations. Not fission, but alpha decay is the dominant decay mode. The collected decay data establish a means of comparison with theoretical data. This aids in the selection of appropriate models that describe the properties of known nuclei. Predictions based on these models are useful in the preparation of the next generation of experiments. Cross-sections decrease by two orders of magnitude from bohrium (Z=107) to element 112, for which a cross-section of 1 pb was measured. The development of intense beam currents and sensitive detection methods is essential for the production and identification of still heavier elements and new isotopes of already known elements, as well as the measurement of small α-, β- and fission-branching ratios. An equally sensitive set-up is needed for the measurement of excitation functions at low cross-sections. Based on our results, it is likely that the production of isotopes of element 114 close to the island of spherical super heavy elements (SHE) could be achieved by fusion reactions using 208 Pb targets. Systematic studies of the reaction cross-sections indicate that the transfer of nucleons is an important process for the initiation of fusion. The data allow for the fixing of a narrow energy window for the production of SHE using 1n-emission channels. (orig.)

  11. Finite element modeling of piezoelectric elements with complex electrode configuration

    International Nuclear Information System (INIS)

    Paradies, R; Schläpfer, B

    2009-01-01

    It is well known that the material properties of piezoelectric materials strongly depend on the state of polarization of the individual element. While an unpolarized material exhibits mechanically isotropic material properties in the absence of global piezoelectric capabilities, the piezoelectric material properties become transversally isotropic with respect to the polarization direction after polarization. Therefore, for evaluating piezoelectric elements the material properties, including the coupling between the mechanical and the electromechanical behavior, should be addressed correctly. This is of special importance for the micromechanical description of piezoelectric elements with interdigitated electrodes (IDEs). The best known representatives of this group are active fiber composites (AFCs), macro fiber composites (MFCs) and the radial field diaphragm (RFD), respectively. While the material properties are available for a piezoelectric wafer with a homogeneous polarization perpendicular to its plane as postulated in the so-called uniform field model (UFM), the same information is missing for piezoelectric elements with more complex electrode configurations like the above-mentioned ones with IDEs. This is due to the inhomogeneous field distribution which does not automatically allow for the correct assignment of the material, i.e. orientation and property. A variation of the material orientation as well as the material properties can be accomplished by including the polarization process of the piezoelectric transducer in the finite element (FE) simulation prior to the actual load case to be investigated. A corresponding procedure is presented which automatically assigns the piezoelectric material properties, e.g. elasticity matrix, permittivity, and charge vector, for finite element models (FEMs) describing piezoelectric transducers according to the electric field distribution (field orientation and strength) in the structure. A corresponding code has been

  12. A suitable low-order, eight-node tetrahedral finite element for solids

    International Nuclear Information System (INIS)

    Key, S.W.; Heinstein, M.S.; Stone, C.M.; Mello, F.J.; Blanford, M.L.; Budge, K.G.

    1998-03-01

    To use the all-tetrahedral mesh generation existing today, the authors have explored the creation of a computationally efficient eight-node tetrahedral finite element (a four-node tetrahedral finite element enriched with four mid-face nodal points). The derivation of the element's gradient operator, studies in obtaining a suitable mass lumping, and the element's performance in applications are presented. In particular they examine the eight-node tetrahedral finite element's behavior in longitudinal plane wave propagation, in transverse cylindrical wave propagation, and in simulating Taylor bar impacts. The element samples only constant strain states and, therefore, has 12 hour-glass modes. In this regard it bears similarities to the eight-node, mean-quadrature hexahedral finite element. Comparisons with the results obtained from the mean-quadrature eight-node hexahedral finite element and the four-node tetrahedral finite element are included. Given automatic all-tetrahedral meshing, the eight-node, constant-strain tetrahedral finite element is a suitable replacement for the eight-node hexahedral finite element in those cases where mesh generation requires an inordinate amount of user intervention and direction to obtain acceptable mesh properties

  13. Studies on tender wheatgrass: estimation of elemental content, bioaccessibility of essential elements and antioxidant activity

    International Nuclear Information System (INIS)

    Reddy, A.V.R.; Acharya, R.; Nair, A.G.C.; Kulkarni, S.D.; Rajurkar, N.S.

    2008-08-01

    Tender wheatgrass is being consumed by human beings in juice form or as it is due to its antioxidant potential and medicinal value. Systematic studies were carried out to (i) estimate elemental profiles as a function of growth period and conditions, bioaccessibility of different elements and the antioxidant potential of the tender wheatgrass, (ii) determine the optimum growth period for obtaining maximum benefit and (iii) examine the possible correlation between antioxidant potential and mineral content. Wheatgrass was grown in four different conditions namely (i) tap water, (ii) tap water with nutrients, (iii) soil and tap water and (iv) soil with nutrient solution. The studies were carried out on the wheatgrass of 5-20 days old. For comparison with laboratory grown wheatgrass, a set of commercially available wheatgrass tablets and wheat seeds were also studied. Instrumental neutron activation analysis (INAA) was used for concentration determination of elements in the wheatgrass, wheat seeds and wheatgrass tablets. A total of 15 elements like Na, K, Ca, Mg, Mn, Br, Fe and Zn were determined in the samples of shoots and roots of tender wheatgrass. A comparison with the recommended dietary allowance (RDA) of different essential elements with that in tender wheatgrass revealed that wheatgrass is a good source of minerals for health benefits rather than a food supplement. Bioaccessible fractions of various elements were estimated by a chemical NAA method by subjecting the samples to in vitro gastric and gastro-intestinal digestion followed by NAA. The bioaccessibility concentrations by both the measurements were in the range of 9-60%. It was found that bioaccessibility of the elements studied was the highest from fresh wheatgrass and the lowest from wheat seeds. Accuracy of the NAA method was evaluated by analyzing two biological reference materials, SRM 1573a (Tomato leaves) from NIST, USA and ICHTJ CTA-vtl-2 (Tobacco leaves) from INCT, Poland. The antioxidant

  14. Brain trace elements and aging

    International Nuclear Information System (INIS)

    Hebbrecht, Geert; Maenhaut, Willy; Reuck, Jacques de

    1999-01-01

    Degenerative mechanisms involved in the aging process of the brain are to a certain extent counteracted by repair mechanisms. In both degenerative and recovery processes, trace elements are involved. The present study focused on the role of two minor (i.e., K and Ca) and six trace elements (i.e., Mn, Fe, Cu, Zn, Se and Rb) in the aging process. The elements were determined by PIXE in cerebral cortex and white matter, basal ganglia, brainstem and cerebellar cortex of 18 postmortem human brains, from persons without a history of neurologic or psychiatric disease who deceased between the age of 7 and 79. This age range allowed us to study the relationship between elemental concentrations and age. The most prominent findings were a concentration decrease for K and Rb and a concentration increase for the elements Ca, Fe, Zn and Se. The study supports recent findings that Ca and Fe are involved in brain degenerative processes initiated by oxygen free radicals, whereas Zn and Se are involved in immunological reactions counteracting the aging process

  15. Correction for interelement effect in X-Ray fluorescence analysis of trace elements in geological materials

    International Nuclear Information System (INIS)

    El-Behay, A.Z.; Attawiya, M.Y.; Khattab, F.M.

    1984-01-01

    In a trial to obtain accurate results from X-ray fluorescence technique for the analysis of trace elements in geological materials, two corrections were used for the obtained data, namely, correction for the observed x-ray intensities for absorption and/or enhancement effects due to the presence of other elements in the system and correction for spectral deconvolution to account for the overlapping lines. Significant improvement in the precision and accuracy was obtained and evaluated

  16. Validation of High Displacement Piezoelectric Actuator Finite Element Models

    Science.gov (United States)

    Taleghani, B. K.

    2000-01-01

    The paper presents the results obtained by using NASTRAN(Registered Trademark) and ANSYS(Regitered Trademark) finite element codes to predict doming of the THUNDER piezoelectric actuators during the manufacturing process and subsequent straining due to an applied input voltage. To effectively use such devices in engineering applications, modeling and characterization are essential. Length, width, dome height, and thickness are important parameters for users of such devices. Therefore, finite element models were used to assess the effects of these parameters. NASTRAN(Registered Trademark) and ANSYS(Registered Trademark) used different methods for modeling piezoelectric effects. In NASTRAN(Registered Trademark), a thermal analogy was used to represent voltage at nodes as equivalent temperatures, while ANSYS(Registered Trademark) processed the voltage directly using piezoelectric finite elements. The results of finite element models were validated by using the experimental results.

  17. Multivariant analyses of trace element patterns for environmental tracking

    International Nuclear Information System (INIS)

    Jervis, R.E.; Ko, M.M.C.; Junliang Tian; Puling Liu

    1993-01-01

    Nuclear-based analytical techniques: INAA, PIXE and photon activation permit simultaneous multielemental determination of concentrations in environmental materials, which data are often found sufficiently precise and free of uncontrolled, random errors among the various elements such that the data sets can yield valuable information on elemental communality through multi-variant statistical 'factor' analysis. Characteristic factor patterns obtained in this way can provide clues to the likely sources in the environment of various components. Recent studies in three different environmental situations: solid waste incinerators , Chinese soils, and iron and steel industry, involving measurements of 30-35 elements, have yielded distinct elemental patterns or, environmental signatures, with factor loading coefficients ranging mostly in the ranges: 0.7-0.96. (author) 10 refs.; 2 figs.; 9 tabs

  18. Evaluation of Concrete Cylinder Tests Using Finite Elements

    DEFF Research Database (Denmark)

    Saabye Ottosen, Niels

    1984-01-01

    Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete is emplo......Nonlinear axisymmetric finite element analyses are performed on the uniaxial compressive test of concrete cylinders. The models include thick steel loading plates, and cylinders with height‐to‐diameter ratios (h/d) ranging from 1‐3 are treated. A simple constitutive model of the concrete...... uniaxial strength the use of geometrically matched loading plates seems to be advantageous. Finally, it is observed that for variations of the element size within limits otherwise required to obtain a realistic analysis, the results are insensitive to the element size....

  19. Application of finite element numerical technique to nuclear reactor geometries

    Energy Technology Data Exchange (ETDEWEB)

    Rouai, N M [Nuclear engineering department faculty of engineering Al-fateh universty, Tripoli (Libyan Arab Jamahiriya)

    1995-10-01

    Determination of the temperature distribution in nuclear elements is of utmost importance to ensure that the temperature stays within safe limits during reactor operation. This paper discusses the use of Finite element numerical technique (FE) for the solution of the two dimensional heat conduction equation in geometries related to nuclear reactor cores. The FE solution stats with variational calculus which considers transforming the heat conduction equation into an integral equation I(O) and seeks a function that minimizes this integral and hence gives the solution to the heat conduction equation. In this paper FE theory as applied to heat conduction is briefly outlined and a 2-D program is used to apply the theory to simple shapes and to two gas cooled reactor fuel elements. Good results are obtained for both cases with reasonable number of elements. 7 figs.

  20. Application of finite element numerical technique to nuclear reactor geometries

    International Nuclear Information System (INIS)

    Rouai, N. M.

    1995-01-01

    Determination of the temperature distribution in nuclear elements is of utmost importance to ensure that the temperature stays within safe limits during reactor operation. This paper discusses the use of Finite element numerical technique (FE) for the solution of the two dimensional heat conduction equation in geometries related to nuclear reactor cores. The FE solution stats with variational calculus which considers transforming the heat conduction equation into an integral equation I(O) and seeks a function that minimizes this integral and hence gives the solution to the heat conduction equation. In this paper FE theory as applied to heat conduction is briefly outlined and a 2-D program is used to apply the theory to simple shapes and to two gas cooled reactor fuel elements. Good results are obtained for both cases with reasonable number of elements. 7 figs