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Sample records for networks mo sha

  1. O P Sha

    Indian Academy of Sciences (India)

    Home; Journals; Sadhana. O P Sha. Articles written in Sadhana. Volume 31 Issue 5 October 2006 pp 645-659. An investigation into design of fair surfaces over irregular domains using data-dependent triangulation · R Sharma O P Sha · More Details Abstract Fulltext PDF. Design of fair surfaces over irregular domains is a ...

  2. Dicty_cDB: SHA444 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available library) SHA444 (Link to dictyBase) - - - Contig-U11259-1 SHA444P (Link to Original site) SHA444F 155 SHA444Z...SHA444Z 795 SHA444P 930 - - Show SHA444 Library SH (Link to library) Clone ID SHA444 (Link to dictyBase)...tsukuba.ac.jp/CSM/SH/SHA4-B/SHA444Q.Seq.d/ Representative seq. ID SHA444P (Link to Original site) Representative...Representative DNA sequence >SHA444 (SHA444Q) /CSM/SH/SHA4-B/SHA444Q.Seq.d/ ATTGTATTATTATTTTTTTAATTTTAT...significant alignments: (bits) Value SHA444 (SHA444Q) /CSM/SH/SHA4-B/SHA444Q.Seq.d/ 1423 0.0 AHL862 (AHL862Q)

  3. Preimages for Step-Reduced SHA-2

    DEFF Research Database (Denmark)

    Aoki, Kazumaro; Guo, Jian; Matusiewicz, Krystian

    2009-01-01

    In this paper, we present preimage attacks on up to 43-step SHA-256 (around 67% of the total 64 steps) and 46-step SHA-512 (around 57.5% of the total 80 steps), which significantly increases the number of attacked steps compared to the best previously published preimage attack working for 24 steps....... The time complexities are 2^251.9, 2^509 for finding pseudo-preimages and 2^254.9, 2^511.5 compression function operations for full preimages. The memory requirements are modest, around 2^6 words for 43-step SHA-256 and 46-step SHA-512. The pseudo-preimage attack also applies to 43-step SHA-224 and SHA-384....... Our attack is a meet-in-the-middle attack that uses a range of novel techniques to split the function into two independent parts that can be computed separately and then matched in a birthday-style phase....

  4. Freestart collision for full SHA-1

    NARCIS (Netherlands)

    M.M.J. Stevens (Marc); P. Karpman (Pierre); T. Peyrin (Thomas)

    2015-01-01

    htmlabstractWe present in this article a freestart collision example for SHA-1, i.e., a collision for its internal compression function. This is the first practical break of the full SHA-1, reaching all 80 out of 80 steps, while only 10 days of computation on a 64 GPU cluster were necessary to

  5. Dicty_cDB: SHA353 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SH (Link to library) SHA353 (Link to dictyBase) - - - Contig-U15708-1 SHA353P (Link to Original site) SHA353F...(Link to library) Clone ID SHA353 (Link to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig...Contig-U15708-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/SH/SHA3-C/SHA353Q.Seq.d/ Representative...Representative seq. ID SHA353P (Link to Original site) Representative DNA sequence >SHA353 (SHA353Q) /CSM/SH/SHA3-C/SHA353Q...Seq.d/ CAATATAATCCATTAATATTAAATTAATTTCATTTTATTGCATGTAATATAATAATAAAT AAAATAAAATAAAATAAAATAAAATAAAATAAAAA

  6. Dicty_cDB: SHA307 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SH (Link to library) SHA307 (Link to dictyBase) - - - Contig-U16439-1 SHA307P (Link to Original site) SHA307F...(Link to library) Clone ID SHA307 (Link to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig...Contig-U16439-1 Original site URL http://dictycdb.biol.tsukuba.ac.jp/CSM/SH/SHA3-A/SHA307Q.Seq.d/ Representative...Representative seq. ID SHA307P (Link to Original site) Representative DNA sequence >SHA307 (SHA307Q) /CSM/SH/SHA3-A/SHA307Q...TGTTTATAATTACAAATAACTATTTTTATATTTTTATATTTATTATTTTTTTTAATATAT TTTTTTATTTTCATTTTTTTGTATAAACTTACATAAAAA

  7. Open Source Seismic Hazard Analysis Software Framework (OpenSHA)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — OpenSHA is an effort to develop object-oriented, web- & GUI-enabled, open-source, and freely available code for conducting Seismic Hazard Analyses (SHA). Our...

  8. Dicty_cDB: SHA665 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SH (Link to library) SHA665 (Link to dictyBase) - - - Contig-U15540-1 - (Link to Or...iginal site) - - SHA665Z 676 - - - - Show SHA665 Library SH (Link to library) Clone ID SHA665 (Link to dicty...Base) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U15540-1 Original site URL http://dictycdb.b...TQIDDKTGIFDSQRFLAFNNPQAMSKYESYRIYIHPSLGY SGNAKRFKQQPDVNEKALILDGNVYDGHLNPIYNCKICTE...ACWNLLEPMHR NYYQPIQFKLPSFPDTSLPITQIDDKTGIFDSQRFLAFNNPQAMSKYESYRIYIHPSLGY SGNAKRFKQQPDVNEKALILDGNVYDGHLNPIYNCKICT

  9. Dicty_cDB: SHA393 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SH (Link to library) SHA393 (Link to dictyBase) - - - Contig-U11503-1 SHA393E (Link... Clone ID SHA393 (Link to dictyBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U11503-1 Original site URL http://dict...lated Amino Acid sequence ekqfsl*iy*YMIRKSNNFSILFAIFLKIVFVVSAPLCPNSTILLNYNILTVYNSSEGCG FNNXPICTSLKDAVXRAFLLI...yhcysyfg Translated Amino Acid sequence (All Frames) Frame A: ekqfsl*iy*YMIRKSNNFSILFAIFLKIVFVVSAPLCPNSTILLNYNILTVYNSSEGCG FNNXPICT...Homology vs Protein Score E Sequences producing significant alignments: (bits) Value AF020283_1( AF020283 |pid:none) Dict

  10. Visual setup of logical models of signaling and regulatory networks with ProMoT

    Directory of Open Access Journals (Sweden)

    Gilles Ernst

    2006-11-01

    Full Text Available Abstract Background The analysis of biochemical networks using a logical (Boolean description is an important approach in Systems Biology. Recently, new methods have been proposed to analyze large signaling and regulatory networks using this formalism. Even though there is a large number of tools to set up models describing biological networks using a biochemical (kinetic formalism, however, they do not support logical models. Results Herein we present a flexible framework for setting up large logical models in a visual manner with the software tool ProMoT. An easily extendible library, ProMoT's inherent modularity and object-oriented concept as well as adaptive visualization techniques provide a versatile environment. Both the graphical and the textual description of the logical model can be exported to different formats. Conclusion New features of ProMoT facilitate an efficient set-up of large Boolean models of biochemical interaction networks. The modeling environment is flexible; it can easily be adapted to specific requirements, and new extensions can be introduced. ProMoT is freely available from http://www.mpi-magdeburg.mpg.de/projects/promot/.

  11. Visual setup of logical models of signaling and regulatory networks with ProMoT.

    Science.gov (United States)

    Saez-Rodriguez, Julio; Mirschel, Sebastian; Hemenway, Rebecca; Klamt, Steffen; Gilles, Ernst Dieter; Ginkel, Martin

    2006-11-17

    The analysis of biochemical networks using a logical (Boolean) description is an important approach in Systems Biology. Recently, new methods have been proposed to analyze large signaling and regulatory networks using this formalism. Even though there is a large number of tools to set up models describing biological networks using a biochemical (kinetic) formalism, however, they do not support logical models. Herein we present a flexible framework for setting up large logical models in a visual manner with the software tool ProMoT. An easily extendible library, ProMoT's inherent modularity and object-oriented concept as well as adaptive visualization techniques provide a versatile environment. Both the graphical and the textual description of the logical model can be exported to different formats. New features of ProMoT facilitate an efficient set-up of large Boolean models of biochemical interaction networks. The modeling environment is flexible; it can easily be adapted to specific requirements, and new extensions can be introduced. ProMoT is freely available from http://www.mpi-magdeburg.mpg.de/projects/promot/.

  12. 76 FR 11433 - Federal Transition To Secure Hash Algorithm (SHA)-256

    Science.gov (United States)

    2011-03-02

    ... Hash Algorithm (SHA)-256 AGENCY: Department of Defense (DoD), General Services Administration (GSA... agencies about ways for the acquisition community to transition to Secure Hash Algorithm SHA-256. SHA-256... Hash Algorithm SHA-256'' in all correspondence related to this public meeting. FOR FURTHER INFORMATION...

  13. Improving SHA-1 counter-cryptanalysis using unavoidable conditions

    OpenAIRE

    Shumow, D.; Stevens, Marc

    2015-01-01

    textabstractThe concept of counter-cryptanalysis and a collision detection algorithm that detects whether a given single message was constructed using a cryptanalytic collision attack on MD5 or SHA-1 was presented by Stevens at CRYPTO 2013. It was shown that collision detection is not only possible but also practical and a reference implementation was released. However, there is a significant cost: to detect collision attacks against SHA-1 (respectively MD5) costs the equivalent of hashing th...

  14. D.SYM.4 SHA-3 Design and Cryptanalysis Report

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Thomsen, Søren Steffen

    2011-01-01

    The competition to select a new secure hash function standard SHA-3 was initiated in response to surprising progress in the cryptanalysis of existing hash function constructions that started in 2004. In this report we survey design and cryptanalytic results of those 14 candidates that remain......, this seems to suggest that a lot of cryptanalysis remains to be done to allow for comparisons, and also to get the level of assurance that will be expected from a future SHA-3....

  15. Hierarchical MoS2-coated three-dimensional graphene network for enhanced supercapacitor performances

    Science.gov (United States)

    Zhou, Rui; Han, Cheng-jie; Wang, Xiao-min

    2017-06-01

    Layered molybdenum disulfide (MoS2) owns graphene-like two-dimensional structure, and when used as the electrode material for energy storage devices, the intercalation of electrolyte ions is permitted. Herein, a simple dipping and drying method is employed to stack few-layered MoS2 nanosheets on a three-dimensional graphene network (3DGN). The structure measurement results indicate that the assembled hierarchical MoS2 nanosheets own expanded interlayer spacing (∼0.75 nm) and are stacked on the surface of 3DGN uncontinuously. The composite can achieve 110.57% capacitance retention after 4000 cycles of galvanostatic charge/discharge tests and 76.73% capacitance retention with increasing the current density from 1 A g-1 to 100 A g-1. Moreover, the asymmetric coin cell supercapacitor using MoS2@3DGN and active carbon as electrode materials is assembled. This device could achieve a working voltage window of 1.6 V along with the power and energy densities of 400.0-8001.6 W kg-1 and 36.43-1.12 Wh kg-1 respectively. The enhanced electrochemical performance can be attributed to: (1) the expanded interlayer spacing of hierarchical MoS2 nanosheets which can facilitate the fast intercalation/deintercalation of electrolyte cations, (2) the uncontinuous deposition of hierarchical MoS2 nanosheets which facilitates more contact between electrolyte and the section of MoS2 nanosheets to provide more gates for the intercalation/deintercalation.

  16. Realtime Automation Networks in moVing industrial Environments

    Directory of Open Access Journals (Sweden)

    Rafael Leidinger

    2012-04-01

    Full Text Available The radio-based wireless data communication has made the realization of new technical solutions possible in many fields of the automation technology (AT. For about ten years, a constant disproportionate growth of wireless technologies can be observed in the automation technology. However, it shows that especially for the AT, conven-tional technologies of office automation are unsuitable and/or not manageable. The employment of mobile ser-vices in the industrial automation technology has the potential of significant cost and time savings. This leads to an increased productivity in various fields of the AT, for example in the factory and process automation or in production logistics. In this paper technologies and solu-tions for an automation-suited supply of mobile wireless services will be introduced under the criteria of real time suitability, IT-security and service orientation. Emphasis will be put on the investigation and develop-ment of wireless convergence layers for different radio technologies, on the central provision of support services for an easy-to-use, central, backup enabled management of combined wired / wireless networks and on the study on integrability in a Profinet real-time Ethernet network [1].

  17. Design and implementation of the broadband network access system over MoCA

    Science.gov (United States)

    Huang, Jing; Liu, Deming; Wu, Guangsheng

    2009-08-01

    In order to provide a high speed scheme for the access of the "last 100 meters", a composite access scheme of EPON and MoCA is proposed in this paper. At the terminal node of FTTX in EPON system, MoCA technique is used to implement broadband data access by distributing network entering household through Coax. A terminal equipment is designed in this scheme, which can receive the optical signal from the OLT of EPON and transform it into RF signal. The end users will receive the RF signal either from the coaxial cable or a RF antenna. This scheme is particularly applicable for FTTB application.There are many advantages in this system, it can provide a reliable room to room, peer to peer full mesh connectivity of digital content among MoCA devices using existing in-home coaxial cables. Plug and play at the majority of serviceable coax outlets in homes with no need to access or change splitters, or run new cables. What's more, it has higher bandwidth and better management. Two group of tests for the EPON+MoCA system were carried out, one for the coaxial cable and one for wireless. The experimental results showed that the average throughput of the system could reach to approximate 100 Mbps which approach to the theoretical throughput of MoCA 1.0 standard. And the transmission throughput had no remarkable change when the RF antenna replaced the coaxial cable.

  18. A Network Model and Computational Approach for the Mo-99 Supply Chain for Nuclear Medicine

    Science.gov (United States)

    Nagurney, Ladimer; Nagurney, Anna

    2011-11-01

    Technetium-99m, produced from the decay of Molybdenum-99, is the most commonly used radioisotope for medical imaging, specifically in cardiac and cancer diagnostics. The MO-99 is produced in a small number of reactors and is processed and distributed worldwide. We have developed a tractable network model and computational approach for the design and redesign of the MO-99 supply chains. This topic is of special relevance to medical physics given the product's widespread use and the aging of the nuclear reactors where it is produced. This generalized network model, for which we derived formulae for the arc and path multipliers that capture the underlying physics of radioisotope decay, includes total operational cost minimization, and the minimization of cost associated with nuclear waste disposal, coupled with capacity investment (or disinvestment) costs. Its solution yields the optimal link capacities as well as the optimal MO-99 flows so that demand at the medical facilities is satisfied. We illustrate the framework with a Western Hemisphere case study. The framework provides the foundation for further empirical research and the basis for the modeling and analysis of supply chain networks for other very time-sensitive medical products.

  19. LDPC and SHA based iris recognition for image authentication

    Directory of Open Access Journals (Sweden)

    K. Seetharaman

    2012-11-01

    Full Text Available We introduce a novel way to authenticate an image using Low Density Parity Check (LDPC and Secure Hash Algorithm (SHA based iris recognition method with reversible watermarking scheme, which is based on Integer Wavelet Transform (IWT and threshold embedding technique. The parity checks and parity matrix of LDPC encoding and cancellable biometrics i.e., hash string of unique iris code from SHA-512 are embedded into an image for authentication purpose using reversible watermarking scheme based on IWT and threshold embedding technique. Simply by reversing the embedding process, the original image, parity checks, parity matrix and SHA-512 hash are extracted back from watermarked-image. For authentication, the new hash string produced by employing SHA-512 on error corrected iris code from live person is compared with hash string extracted from watermarked-image. The LDPC code reduces the hamming distance for genuine comparisons by a larger amount than for the impostor comparisons. This results in better separation between genuine and impostor users which improves the authentication performance. Security of this scheme is very high due to the security complexity of SHA-512, which is 2256 under birthday attack. Experimental results show that this approach can assure more accurate authentication with a low false rejection or false acceptance rate and outperforms the prior arts in terms of PSNR.

  20. Improving SHA-1 counter-cryptanalysis using unavoidable conditions

    NARCIS (Netherlands)

    D. Shumow; M.M.J. Stevens (Marc)

    2015-01-01

    textabstractThe concept of counter-cryptanalysis and a collision detection algorithm that detects whether a given single message was constructed using a cryptanalytic collision attack on MD5 or SHA-1 was presented by Stevens at CRYPTO 2013. It was shown that collision detection is not only possible

  1. Instruction sequence expressions for the secure hash algorithm SHA-256

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2013-01-01

    The secure hash function SHA-256 is a function on bit strings. This means that its restriction to the bit strings of any given length can be computed by a finite instruction sequence that contains only instructions to set and get the content of Boolean registers, forward jump instructions, and a

  2. Second-Preimage Analysis of Reduced SHA-1

    DEFF Research Database (Denmark)

    Rechberger, Christian

    2010-01-01

    Many applications using cryptographic hash functions do not require collision resistance, but some kind of preimage resistance. That's also the reason why the widely used SHA-1 continues to be recommended in all applications except digital signatures after 2010. Recent work on preimage and second...

  3. On security arguments of the second round SHA-3 candidates

    DEFF Research Database (Denmark)

    Andreeva, Elena; Bogdanov, Andrey; Mennink, Bart

    2012-01-01

    In 2007, the US National Institute for Standards and Technology (NIST) announced a call for the design of a new cryptographic hash algorithm in response to vulnerabilities like differential attacks identified in existing hash functions, such as MD5 and SHA-1. NIST received many submissions, 51...... of which got accepted to the first round. 14 candidates were left in the second round, out of which five candidates have been recently chosen for the final round. An important criterion in the selection process is the SHA-3 hash function security. We identify two important classes of security arguments...... for the new designs: (1) the possible reductions of the hash function security to the security of its underlying building blocks and (2) arguments against differential attack on building blocks. In this paper, we compare the state of the art provable security reductions for the second round candidates...

  4. Prediction of U-Mo dispersion nuclear fuels with Al-Si alloy using artificial neural network

    Energy Technology Data Exchange (ETDEWEB)

    Susmikanti, Mike, E-mail: mike@batan.go.id [Center for Development of Nuclear Informatics, National Nuclear Energy Agency, PUSPIPTEK, Tangerang (Indonesia); Sulistyo, Jos, E-mail: soj@batan.go.id [Center for Nuclear Facilities Engineering, National Nuclear Energy Agency, PUSPIPTEK, Tangerang (Indonesia)

    2014-09-30

    Dispersion nuclear fuels, consisting of U-Mo particles dispersed in an Al-Si matrix, are being developed as fuel for research reactors. The equilibrium relationship for a mixture component can be expressed in the phase diagram. It is important to analyze whether a mixture component is in equilibrium phase or another phase. The purpose of this research it is needed to built the model of the phase diagram, so the mixture component is in the stable or melting condition. Artificial neural network (ANN) is a modeling tool for processes involving multivariable non-linear relationships. The objective of the present work is to develop code based on artificial neural network models of system equilibrium relationship of U-Mo in Al-Si matrix. This model can be used for prediction of type of resulting mixture, and whether the point is on the equilibrium phase or in another phase region. The equilibrium model data for prediction and modeling generated from experimentally data. The artificial neural network with resilient backpropagation method was chosen to predict the dispersion of nuclear fuels U-Mo in Al-Si matrix. This developed code was built with some function in MATLAB. For simulations using ANN, the Levenberg-Marquardt method was also used for optimization. The artificial neural network is able to predict the equilibrium phase or in the phase region. The develop code based on artificial neural network models was built, for analyze equilibrium relationship of U-Mo in Al-Si matrix.

  5. Prediction of U-Mo dispersion nuclear fuels with Al-Si alloy using artificial neural network

    Science.gov (United States)

    Susmikanti, Mike; Sulistyo, Jos

    2014-09-01

    Dispersion nuclear fuels, consisting of U-Mo particles dispersed in an Al-Si matrix, are being developed as fuel for research reactors. The equilibrium relationship for a mixture component can be expressed in the phase diagram. It is important to analyze whether a mixture component is in equilibrium phase or another phase. The purpose of this research it is needed to built the model of the phase diagram, so the mixture component is in the stable or melting condition. Artificial neural network (ANN) is a modeling tool for processes involving multivariable non-linear relationships. The objective of the present work is to develop code based on artificial neural network models of system equilibrium relationship of U-Mo in Al-Si matrix. This model can be used for prediction of type of resulting mixture, and whether the point is on the equilibrium phase or in another phase region. The equilibrium model data for prediction and modeling generated from experimentally data. The artificial neural network with resilient backpropagation method was chosen to predict the dispersion of nuclear fuels U-Mo in Al-Si matrix. This developed code was built with some function in MATLAB. For simulations using ANN, the Levenberg-Marquardt method was also used for optimization. The artificial neural network is able to predict the equilibrium phase or in the phase region. The develop code based on artificial neural network models was built, for analyze equilibrium relationship of U-Mo in Al-Si matrix.

  6. Addendum: Safety Standards for Gua sha (press-stroking) and Ba guan (cupping).

    Science.gov (United States)

    Nielsen, Arya; Kligler, Ben; Koll, Brian S

    2014-06-01

    Our previous article Safety Standards for Gua sha (press-stroking) and Baguan (cupping) discussed the risk of transfer of blood-borne pathogens with Gua sha and Ba guan, identified Gua sha and Ba guan 'instrument criticality' as semi-critical and offered recommendations for safe practice based on hospital disinfection standards. Based on the article's feedback, we feel the need to clarify that Gua sha and Ba guan instruments, if intended for reuse, must undergo high level disinfection (HLD) or, in the case of 'wet-cupping', sterilization. We update our recommendations to be amenable to both private practice and education settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Data harmonization and federated analysis of population-based studies: the BioSHaRE project.

    Science.gov (United States)

    Doiron, Dany; Burton, Paul; Marcon, Yannick; Gaye, Amadou; Wolffenbuttel, Bruce H R; Perola, Markus; Stolk, Ronald P; Foco, Luisa; Minelli, Cosetta; Waldenberger, Melanie; Holle, Rolf; Kvaløy, Kirsti; Hillege, Hans L; Tassé, Anne-Marie; Ferretti, Vincent; Fortier, Isabel

    2013-11-21

    Individual-level data pooling of large population-based studies across research centres in international research projects faces many hurdles. The BioSHaRE (Biobank Standardisation and Harmonisation for Research Excellence in the European Union) project aims to address these issues by building a collaborative group of investigators and developing tools for data harmonization, database integration and federated data analyses. Eight population-based studies in six European countries were recruited to participate in the BioSHaRE project. Through workshops, teleconferences and electronic communications, participating investigators identified a set of 96 variables targeted for harmonization to answer research questions of interest. Using each study's questionnaires, standard operating procedures, and data dictionaries, harmonization potential was assessed. Whenever harmonization was deemed possible, processing algorithms were developed and implemented in an open-source software infrastructure to transform study-specific data into the target (i.e. harmonized) format. Harmonized datasets located on server in each research centres across Europe were interconnected through a federated database system to perform statistical analysis. Retrospective harmonization led to the generation of common format variables for 73% of matches considered (96 targeted variables across 8 studies). Authenticated investigators can now perform complex statistical analyses of harmonized datasets stored on distributed servers without actually sharing individual-level data using the DataSHIELD method. New Internet-based networking technologies and database management systems are providing the means to support collaborative, multi-center research in an efficient and secure manner. The results from this pilot project show that, given a strong collaborative relationship between participating studies, it is possible to seamlessly co-analyse internationally harmonized research databases while allowing

  8. Mapping PetaSHA Applications to TeraGrid Architectures

    Science.gov (United States)

    Cui, Y.; Moore, R.; Olsen, K.; Zhu, J.; Dalguer, L. A.; Day, S.; Cruz-Atienza, V.; Maechling, P.; Jordan, T.

    2007-12-01

    The Southern California Earthquake Center (SCEC) has a science program in developing an integrated cyberfacility - PetaSHA - for executing physics-based seismic hazard analysis (SHA) computations. The NSF has awarded PetaSHA 15 million allocation service units this year on the fastest supercomputers available within the NSF TeraGrid. However, one size does not fit all, a range of systems are needed to support this effort at different stages of the simulations. Enabling PetaSHA simulations on those TeraGrid architectures to solve both dynamic rupture and seismic wave propagation have been a challenge from both hardware and software levels. This is an adaptation procedure to meet specific requirements of each architecture. It is important to determine how fundamental system attributes affect application performance. We present an adaptive approach in our PetaSHA application that enables the simultaneous optimization of both computation and communication at run-time using flexible settings. These techniques optimize initialization, source/media partition and MPI-IO output in different ways to achieve optimal performance on the target machines. The resulting code is a factor of four faster than the orignial version. New MPI-I/O capabilities have been added for the accurate Staggered-Grid Split-Node (SGSN) method for dynamic rupture propagation in the velocity-stress staggered-grid finite difference scheme (Dalguer and Day, JGR, 2007), We use execution workflow across TeraGrid sites for managing the resulting data volumes. Our lessons learned indicate that minimizing time to solution is most critical, in particular when scheduling large scale simulations across supercomputer sites. The TeraShake platform has been ported to multiple architectures including TACC Dell lonestar and Abe, Cray XT3 Bigben and Blue Gene/L. Parallel efficiency of 96% with the PetaSHA application Olsen-AWM has been demonstrated on 40,960 Blue Gene/L processors at IBM TJ Watson Center. Notable

  9. Development of multilayer perceptron networks for isothermal time temperature transformation prediction of U-Mo-X alloys

    Science.gov (United States)

    Johns, Jesse M.; Burkes, Douglas

    2017-07-01

    In this work, a multilayered perceptron (MLP) network is used to develop predictive isothermal time-temperature-transformation (TTT) models covering a range of U-Mo binary and ternary alloys. The selected ternary alloys for model development are U-Mo-Ru, U-Mo-Nb, U-Mo-Zr, U-Mo-Cr, and U-Mo-Re. These model's ability to predict 'novel' U-Mo alloys is shown quite well despite the discrepancies between literature sources for similar alloys which likely arise from different thermal-mechanical processing conditions. These models are developed with the primary purpose of informing experimental decisions. Additional experimental insight is necessary in order to reduce the number of experiments required to isolate ideal alloys. These models allow test planners to evaluate areas of experimental interest; once initial tests are conducted, the model can be updated and further improve follow-on testing decisions. The model also improves analysis capabilities by reducing the number of data points necessary from any particular test. For example, if one or two isotherms are measured during a test, the model can construct the rest of the TTT curve over a wide range of temperature and time. This modeling capability reduces the cost of experiments while also improving the value of the results from the tests. The reduced costs could result in improved material characterization and therefore improved fundamental understanding of TTT dynamics. As additional understanding of phenomena driving TTTs is acquired, this type of MLP model can be used to populate unknowns (such as material impurity and other thermal mechanical properties) from past literature sources.

  10. Development of multilayer perceptron networks for isothermal time temperature transformation prediction of U-Mo-X alloys

    Energy Technology Data Exchange (ETDEWEB)

    Johns, Jesse M.; Burkes, Douglas

    2017-07-01

    In this work, a multilayered perceptron (MLP) network is used to develop predictive isothermal time-temperature-transformation (TTT) models covering a range of U-Mo binary and ternary alloys. The selected ternary alloys for model development are U-Mo-Ru, U-Mo-Nb, U-Mo-Zr, U-Mo-Cr, and U-Mo-Re. These model’s ability to predict 'novel' U-Mo alloys is shown quite well despite the discrepancies between literature sources for similar alloys which likely arise from different thermal-mechanical processing conditions. These models are developed with the primary purpose of informing experimental decisions. Additional experimental insight is necessary in order to reduce the number of experiments required to isolate ideal alloys. These models allow test planners to evaluate areas of experimental interest; once initial tests are conducted, the model can be updated and further improve follow-on testing decisions. The model also improves analysis capabilities by reducing the number of data points necessary from any particular test. For example, if one or two isotherms are measured during a test, the model can construct the rest of the TTT curve over a wide range of temperature and time. This modeling capability reduces the cost of experiments while also improving the value of the results from the tests. The reduced costs could result in improved material characterization and therefore improved fundamental understanding of TTT dynamics. As additional understanding of phenomena driving TTTs is acquired, this type of MLP model can be used to populate unknowns (such as material impurity and other thermal mechanical properties) from past literature sources.

  11. New collision attacks on SHA-1 based on optimal joint local-collision analysis

    NARCIS (Netherlands)

    M.M.J. Stevens (Marc); T. Johansson; P.Q. Nguyen

    2013-01-01

    textabstractThe main contributions of this paper are two-fold. Firstly, we present a novel direction in the cryptanalysis of the cryptographic hash function {\\SHA}. Our work builds on previous cryptanalytic efforts on {\\SHA} based on combinations of local collisions. Due to dependencies,

  12. Magnetic anisotropy of [Mo(CN)7]4- anions and fragments of cyano-bridged magnetic networks.

    Science.gov (United States)

    Chibotaru, Liviu F; Hendrickx, Marc F A; Clima, Sergiu; Larionova, Joulia; Ceulemans, Arnout

    2005-08-18

    Quantum chemistry calculations of CASSCF/CASPT2 level together with ligand field analysis are used for the investigation of magnetic anisotropy of [Mo(CN)7]4- complexes. We have considered three types of heptacyano environments: two ideal geometries, a pentagonal bipyramid and a capped trigonal prism, and the heptacyanomolybdate fragment of the cyano-bridged magnetic network K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O. At all geometries the first excited Kramers doublet is found remarkably close to the ground one due to a small orbital energy gap in the ligand field spectrum, which ranges between a maximal value in the capped trigonal prism (800 cm(-1)) and zero in the pentagonal bipyramid. The small value of this gap explains (i) the axial form of the g tensor and (ii) the strong magnetic anisotropy even in strongly distorted complexes. Comparison with available experimental data for the g tensor of the mononuclear precursors reveals good agreement with the present calculations for the capped trigonal prismatic complex and a significant discrepancy for the pentagonal bipyramidal one. The calculations for the heptacyanomolybdate fragment of K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O give g(perpendicular)/g(parallel) approximately 0.5 and the orientation of the local anisotropy axis close to the symmetry axis of an idealized pentagonal bipyramid. These findings are expected to be important for the understanding of the magnetism of anisotropic Mo(III)-Mn(II) cyano-bridged networks based on the [Mo(CN)7]4- building block.

  13. Bi2 MoO6 Nanostrip Networks for Enhanced Visible-Light Photocatalytic Reduction of CO2 to CH4.

    Science.gov (United States)

    Zhang, Yuan; Li, Liang; Han, Qiutong; Tang, Lanqin; Chen, Xingyu; Hu, Jianqiang; Li, Zhaosheng; Zhou, Yong; Liu, Junming; Zou, Zhigang

    2017-08-29

    A three-dimensional Bi2 MoO6 nanostrip architecture was synthesized by the hydrothermal method using sodium oleate as a surfactant. The generated Bi2 MoO6 nanostrips intercross with each other to form a unique network structure with a band gap of 2.92 eV, corresponding to visible-light wavelength. Time-evolution experiments reveal the formation mechanism of the Bi2 MoO6 network. The photocatalytic reduction of CO2 to CH4 catalyzed by the Bi2 MoO6 architecture was evaluated and compared with the process catalyzed by a Bi2 MoO6 nanoplate analogue synthesized in the absence of sodium oleate as well as with the solid-state reaction. The Bi2 MoO6 nanostrips exhibit the best photocatalytic activity, which can be attributed to their high specific surface area, high light-absorption intensity, suitable thickness for fast charge-carrier migration, and the presence of pores for reactant transport. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Is rigorous retrospective harmonization possible? Application of the DataSHaPER approach across 53 large studies

    NARCIS (Netherlands)

    Fortier, Isabel; Doiron, Dany; Little, Julian; Ferretti, Vincent; L'Heureux, Francois; Stolk, Ronald P.; Knoppers, Bartha M.; Hudson, Thomas J.; Burton, Paul R.

    2011-01-01

    Methods This article examines the value of using the DataSHaPER for retrospective harmonization of established studies. Using the DataSHaPER approach, the potential to generate 148 harmonized variables from the questionnaires and physical measures collected in 53 large population-based studies (6.9

  15. A 3D Active Learning Application for NeMO-Net, the NASA Neural Multi-Modal Observation and Training Network for Global Coral Reef Assessment

    Science.gov (United States)

    van den Bergh, Jarrett; Schutz, Joey; Li, Alan; Chirayath, Ved

    2017-01-01

    NeMO-Net, the NASA neural multi-modal observation and training network for global coral reef assessment, is an open-source deep convolutional neural network and interactive active learning training software aiming to accurately assess the present and past dynamics of coral reef ecosystems through determination of percent living cover and morphology as well as mapping of spatial distribution. We present an interactive video game prototype for tablet and mobile devices where users interactively label morphology classifications over mm-scale 3D coral reef imagery captured using fluid lensing to create a dataset that will be used to train NeMO-Nets convolutional neural network. The application currently allows for users to classify preselected regions of coral in the Pacific and will be expanded to include additional regions captured using our NASA FluidCam instrument, presently the highest-resolution remote sensing benthic imaging technology capable of removing ocean wave distortion, as well as lower-resolution airborne remote sensing data from the ongoing NASA CORAL campaign. Active learning applications present a novel methodology for efficiently training large-scale Neural Networks wherein variances in identification can be rapidly mitigated against control data. NeMO-Net periodically checks users input against pre-classified coral imagery to gauge their accuracy and utilize in-game mechanics to provide classification training. Users actively communicate with a server and are requested to classify areas of coral for which other users had conflicting classifications and contribute their input to a larger database for ranking. In partnering with Mission Blue and IUCN, NeMO-Net leverages an international consortium of subject matter experts to classify areas of confusion identified by NeMO-Net and generate additional labels crucial for identifying decision boundary locations in coral reef assessment.

  16. Quality, quantity and harmony : the DataSHaPER approach to integrating data across bioclinical studies

    NARCIS (Netherlands)

    Fortier, Isabel; Burton, Paul R.; Robson, Paula J.; Ferretti, Vincent; Little, Julian; L'Heureux, Francois; Deschenes, Mylene; Knoppers, Bartha M.; Doiron, Dany; Keers, Joost C.; Linksted, Pamela; Harris, Jennifer R.; Lachance, Genevieve; Boileau, Catherine; Pedersen, Nancy L.; Hamilton, Carol M.; Hveem, Kristian; Borugian, Marilyn J.; Gallagher, Richard P.; McLaughlin, John; Parker, Louise; Potter, John D.; Gallacher, John; Kaaks, Rudolf; Liu, Bette; Sprosen, Tim; Vilain, Anne; Atkinson, Susan A.; Rengifo, Andrea; Morton, Robin; Metspalu, Andres; Wichmann, H. Erich; Tremblay, Mark; Chisholm, Rex L.; Garcia-Montero, Andres; Hillege, Hans; Litton, Jan-Eric; Palmer, Lyle J.; Perola, Markus; Wolffenbuttel, Bruce H. R.; Peltonen, Leena; Hudson, Thomas J.

    2010-01-01

    Methods This conceptual article describes the origins, purpose and scientific foundations of the DataSHaPER (DataSchema and Harmonization Platform for Epidemiological Research; http://www.datashaper.org), which has been created by a multidisciplinary consortium of experts that was pulled together

  17. Side channel analysis of some hash based MACs: A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Okeya, Katsuyuki

    2008-01-01

    The forthcoming NIST's Advanced Hash Standard (AHS) competition to select SHA-3 hash function requires that each candidate hash function submission must have at least one construction to support FIPS 198 HMAC application. As part of its evaluation, NIST is aiming to select either a candidate hash...

  18. NeMO-Net: The Neural Multi-Modal Observation and Training Network for Global Coral Reef Assessment

    Science.gov (United States)

    Chirayath, Ved

    2017-01-01

    In the past decade, coral reefs worldwide have experienced unprecedented stresses due to climate change, ocean acidification, and anthropomorphic pressures, instigating massive bleaching and die-off of these fragile and diverse ecosystems. Furthermore, remote sensing of these shallow marine habitats is hindered by ocean wave distortion, refraction and optical attenuation, leading invariably to data products that are often of low resolution and signal-to-noise (SNR) ratio. However, recent advances in UAV and Fluid Lensing technology have allowed us to capture multispectral 3D imagery of these systems at sub-cm scales from above the water surface, giving us an unprecedented view of their growth and decay. Exploiting the fine-scaled features of these datasets, machine learning methods such as MAP, PCA, and SVM can not only accurately classify the living cover and morphology of these reef systems (below 8 percent error), but are also able to map the spectral space between airborne and satellite imagery, augmenting and improving the classification accuracy of previously low-resolution datasets. We are currently implementing NeMO-Net, the first open-source deep convolutional neural network (CNN) and interactive active learning and training software to accurately assess the present and past dynamics of coral reef ecosystems through determination of percent living cover and morphology. NeMO-Net will be built upon the QGIS platform to ingest UAV, airborne and satellite datasets from various sources and sensor capabilities, and through data-fusion determine the coral reef ecosystem makeup globally at unprecedented spatial and temporal scales. To achieve this, we will exploit virtual data augmentation, the use of semi-supervised learning, and active learning through a tablet platform allowing for users to manually train uncertain or difficult to classify datasets. The project will make use of Pythons extensive libraries for machine learning, as well as extending integration

  19. Insight into the mechanism of action of temporin-SHa, a new broad-spectrum antiparasitic and antibacterial agent

    National Research Council Canada - National Science Library

    Zahid Raja; Sonia André; Feten Abbassi; Vincent Humblot; Olivier Lequin; Tahar Bouceba; Isabelle Correia; Sandra Casale; Thierry Foulon; Denis Sereno; Bruno Oury; Ali Ladram

    2017-01-01

    ...), a small broad-spectrum AMP previously shown to be active against Leishmania infantum. To improve activity, we designed analogs of SHa and compared the antibacterial and antiparasitic mechanisms. [K3...

  20. Insight into the mechanism of action of temporin-SHa, a new broad-spectrum antiparasitic and antibacterial agent.

    Directory of Open Access Journals (Sweden)

    Zahid Raja

    Full Text Available Antimicrobial peptides (AMPs are promising drugs to kill resistant pathogens. In contrast to bacteria, protozoan parasites, such as Leishmania, were little studied. Therefore, the antiparasitic mechanism of AMPs is still unclear. In this study, we sought to get further insight into this mechanism by focusing our attention on temporin-SHa (SHa, a small broad-spectrum AMP previously shown to be active against Leishmania infantum. To improve activity, we designed analogs of SHa and compared the antibacterial and antiparasitic mechanisms. [K3]SHa emerged as a highly potent compound active against a wide range of bacteria, yeasts/fungi, and trypanosomatids (Leishmania and Trypanosoma, with leishmanicidal intramacrophagic activity and efficiency toward antibiotic-resistant strains of S. aureus and antimony-resistant L. infantum. Multipassage resistance selection demonstrated that temporins-SH, particularly [K3]SHa, are not prone to induce resistance in Escherichia coli. Analysis of the mode of action revealed that bacterial and parasite killing occur through a similar membranolytic mechanism involving rapid membrane permeabilization and depolarization. This was confirmed by high-resolution imaging (atomic force microscopy and field emission gun-scanning electron microscopy. Multiple combined techniques (nuclear magnetic resonance, surface plasmon resonance, differential scanning calorimetry allowed us to detail peptide-membrane interactions. [K3]SHa was shown to interact selectively with anionic model membranes with a 4-fold higher affinity (KD = 3 x 10-8 M than SHa. The amphipathic α-helical peptide inserts in-plane in the hydrophobic lipid bilayer and disrupts the acyl chain packing via a detergent-like effect. Interestingly, cellular events, such as mitochondrial membrane depolarization or DNA fragmentation, were observed in L. infantum promastigotes after exposure to SHa and [K3]SHa at concentrations above IC50. Our results indicate that these

  1. Reliable Collection of Real-Time Patient Physiologic Data from less Reliable Networks: a "Monitor of Monitors" System (MoMs).

    Science.gov (United States)

    Hu, Peter F; Yang, Shiming; Li, Hsiao-Chi; Stansbury, Lynn G; Yang, Fan; Hagegeorge, George; Miller, Catriona; Rock, Peter; Stein, Deborah M; Mackenzie, Colin F

    2017-01-01

    Research and practice based on automated electronic patient monitoring and data collection systems is significantly limited by system down time. We asked whether a triple-redundant Monitor of Monitors System (MoMs) to collect and summarize key information from system-wide data sources could achieve high fault tolerance, early diagnosis of system failure, and improve data collection rates. In our Level I trauma center, patient vital signs(VS) monitors were networked to collect real time patient physiologic data streams from 94 bed units in our various resuscitation, operating, and critical care units. To minimize the impact of server collection failure, three BedMaster® VS servers were used in parallel to collect data from all bed units. To locate and diagnose system failures, we summarized critical information from high throughput datastreams in real-time in a dashboard viewer and compared the before and post MoMs phases to evaluate data collection performance as availability time, active collection rates, and gap duration, occurrence, and categories. Single-server collection rates in the 3-month period before MoMs deployment ranged from 27.8 % to 40.5 % with combined 79.1 % collection rate. Reasons for gaps included collection server failure, software instability, individual bed setting inconsistency, and monitor servicing. In the 6-month post MoMs deployment period, average collection rates were 99.9 %. A triple redundant patient data collection system with real-time diagnostic information summarization and representation improved the reliability of massive clinical data collection to nearly 100 % in a Level I trauma center. Such data collection framework may also increase the automation level of hospital-wise information aggregation for optimal allocation of health care resources.

  2. Bicliques for Preimages: Attacks on Skein-512 and the SHA-2 Family

    DEFF Research Database (Denmark)

    Khovratovich, Dmitry; Rechberger, Christian; Savelieva, Alexandra

    2012-01-01

    We present a new concept of biclique as a tool for preimage attacks, which employs many powerful techniques from differential cryptanalysis of block ciphers and hash functions. The new tool has proved to be widely applicable by inspiring many authors to publish new results of the full versions...... of AES, KASUMI, IDEA, and Square. In this paper, we show how our concept leads to the first cryptanalysis of the round-reduced Skein hash function, and describe an attack on the SHA-2 hash function with more rounds than before....

  3. BH-ShaDe: A Software Tool That Assists Architecture Students in the III-Structured Task of Housing Design

    Science.gov (United States)

    Millan, Eva; Belmonte, Maria-Victoria; Ruiz-Montiel, Manuela; Gavilanes, Juan; Perez-de-la-Cruz, Jose-Luis

    2016-01-01

    In this paper, we present BH-ShaDe, a new software tool to assist architecture students learning the ill-structured domain/task of housing design. The software tool provides students with automatic or interactively generated floor plan schemas for basic houses. The students can then use the generated schemas as initial seeds to develop complete…

  4. MO-DE-BRA-04: The CREATE Medical Physics Research Training Network: Training of New Generation Innovators

    Energy Technology Data Exchange (ETDEWEB)

    Seuntjens, J; Collins, L; Devic, S; El Naqa, I; Nadeau, J; Reader, A [McGill University, Montreal, QC (Canada); Beaulieu, L; Despres, P [Centre Hospitalier Univ de Quebec, Quebec, QC (Canada); Pike, B [University of Calgary, Calgary, Alberta (Canada)

    2015-06-15

    Purpose: Over the past century, physicists have played a major role in transforming scientific discovery into everyday clinical applications. However, with the increasingly stringent requirements to regulate medical physics as a health profession, the role of physicists as scientists and innovators has become at serious risk of erosion. These challenges trigger the need for a new, revolutionized training program at the graduate level that respects scientific rigor, attention for medical physics-relevant developments in basic sciences, innovation and entrepreneurship. Methods: A grant proposal was funded by the Collaborative REsearch and Training Experience program (CREATE) of the Natural Sciences and Engineering Research Council (NSERC) of Canada. This enabled the creation of the Medical Physics Research Training Network (MPRTN) around two CAMPEP-accredited medical physics programs. Members of the network consist of medical device companies, government (research and regulatory) and academia. The MPRTN/CREATE program proposes a curriculum with three main themes: (1) radiation physics, (2) imaging & image processing and (3) radiation response, outcomes and modeling. Results: The MPRTN was created mid 2013 (mprtn.com) and features (1) four new basic Ph.D. courses; (2) industry participation in research projects; (3) formal job-readiness training with involvement of guest faculty from academia, government and industry. MPRTN activities since 2013 include 22 conferences; 7 workshops and 4 exchange travels. Three patents were filed or issued, nine awards/best papers were won. Fifteen journal publications were accepted/published, 102 conference abstracts. There are now 13 industry partners. Conclusion: A medical physics research training network has been set up with the goal to harness graduate student’s job-readiness for industry, government and academia in addition to the conventional clinical role. Two years after inception, significant successes have been booked

  5. A Pilot study of the Sharing Risk Information Tool (ShaRIT) for Families with Hereditary Breast and Ovarian Cancer Syndrome

    Science.gov (United States)

    2012-01-01

    Background Individuals who carry deleterious BRCA mutations face significantly elevated risks of breast, ovarian, and other cancers. These individuals are also responsible for informing relatives of their increased risk for carrying the family BRCA mutation. Few interventions have been developed to facilitate this family communication process. Methods We developed the Sharing Risk Information Tool (ShaRIT), a personalized educational intervention, to support BRCA carriers as they discuss BRCA positive results and their implications with relatives. We conducted a pilot study of 19 BRCA carriers identified through the University of California San Francisco Cancer Risk Program. Our study had two aims: 1) to assess the feasibility and acceptability of ShaRIT, and 2) describe characteristics associated with increased family communication and BRCA testing. Participants in our study were divided into two groups: those who had not received ShaRIT as part of their genetic counseling protocol (control group, n = 10) and those who received ShaRIT (n = 9). Results All 9 women who received ShaRIT reported that it was a useful resource. Characteristics associated with increased sharing and testing included: female gender, degree of relationship, and frequency of communication. Increased pedigree knowledge showed a trend toward higher rates of sharing. Conclusions Both participants and genetic counselors considered ShaRIT a well-received, comprehensive tool for disseminating individual risk information and clinical care guidelines to Hereditary Breast and Ovarian Cancer Syndrome families. Because of this, ShaRIT has been incorporated as standard of care at our institution. In the future we hope to evaluate the effects of ShaRIT on family communication and family testing in larger populations of BRCA positive families. PMID:22494806

  6. Nitrate framework directive and cross compliance: two case studies from the MO.NA.CO. monitoring network

    Directory of Open Access Journals (Sweden)

    Marisanna Speroni

    2016-03-01

    Full Text Available The Act A4 refers to Articles 4 and 5 of Directive 91/676 / EEC concerning the protection of waters against pollution caused by nitrates from agricultural sources. The A4 Act applies to farms that have land within a Nitrate Vulnerable Zone (NVZ; it also applies to farms, with or without herds, that participate in measure 214 of the Rural Development Plans. The monitoring was performed in two experimental farms belonging to CREA-FLC. Both monitoring sites are located in  vulnerable areas designated by the Lombardy Region. In the monitoring period MO.NA.CO., the regional standard of reference were the Decrees of the Regional Government DGR5868 / 2007 and DGR2208 / 2011. The average cost attributable to administrative requirements was about € 600 / year / company and was mainly due to a professional agronomist who prepared the Agronomic Utilization Plan (PUA, assisted the farm in preparing its communication, provided advice and informed farm managers on regulatory updates. An informal, not systematic survey made possible to detect that the cost to fulfil the obligations of communication can be very variable depending on the farm’s characteristics (size, production, size of the herd and the type of consultant assisting the breeder (freelancer, association, cooperative. For example, in some cases the cost is based on the area of the farm, in others on the number of animals in the herd; and in other situations, the associations and freelance agronomist apply a flat rate for the compilation of the PUAs which is unaffected by farm characteristics and ranging from a minimum of € 100 / year / company practiced by some farmers’ association to a maximum of € 800 / year / company required by some freelance agronomist. At Baroncina farm the storage capacity of the slurry, during the monitoring period, was not compliant with the law because the volumes produced could not be stocked for 120 days as required by the standard. New storage facilities

  7. A Novel Digital Background Calibration Technique for 16 bit SHA-less Multibit Pipelined ADC

    Directory of Open Access Journals (Sweden)

    Swina Narula

    2016-01-01

    Full Text Available In this paper, a high resolution of 16 bit and high speed of 125MS/s, multibit Pipelined ADC with digital background calibration is presented. In order to achieve low power, SHA-less front end is used with multibit stages. The first and second stages are used here as a 3.5 bit and the stages from third to seventh are of 2.5 bit and last stage is of 3-bit flash ADC. After bit alignment and truncation of total 19 bits, 16 bits are used as final digital output. To precise the remove linear gain error of the residue amplifier and capacitor mismatching error, a digital background calibration technique is used, which is a combination of signal dependent dithering (SDD and butterfly shuffler. To improve settling time of residue amplifier, a special circuit of voltage separation is used. With the proposed digital background calibration technique, the spurious-free dynamic range (SFDR has been improved to 97.74 dB @30 MHz and 88.9 dB @150 MHz, and the signal-to-noise and distortion ratio (SNDR has been improved to 79.77 dB @ 30 MHz, and 73.5 dB @ 150 MHz. The implementation of the Pipelined ADC has been completed with technology parameters of 0.18μm CMOS process with 1.8 V supply. Total power consumption is 300 mW by the proposed ADC.

  8. SHA.DIF.14k: a new archaeomagnetic model for the Holocene period

    Science.gov (United States)

    Pavon-Carrasco, F. Javier; Osete, M. Luisa; Miquel Torta, J.; De Santis, Angelo

    2014-05-01

    A new global model of the Earth's magnetic field based on archaeomagnetic and lava flow data covering the Holocene period, from 12000BC to 1900AD, is presented. This model, called SHA.DIF.14k, was developed in space using the spherical harmonic analysis and in time using the penalized cubic b-splines. According to the model predictions, the dipolar moment of the Earth's magnetic field shows a minimum during the Neolithic (between 5500BC to 3000BC), then a maximum around 500 BC, followed by the well-known decreasing trend of the last two millennia. The north magnetic dip pole is characterized by a mean rate of motion of 5.1 km/yr for the last 14ka (6.3 km/yr for the last 8ka) and it can be averaged as axial dipolar in about 2000 yr within an error of 5º, the classical error of palaeomagnetic studies, although the rigorous geocentric axial dipole (GAD) hypothesis is reached when it is averaged over more than 10000 yr.

  9. Fault2SHA- A European Working group to link faults and Probabilistic Seismic Hazard Assessment communities in Europe

    Science.gov (United States)

    Scotti, Oona; Peruzza, Laura

    2016-04-01

    The key questions we ask are: What is the best strategy to fill in the gap in knowledge and know-how in Europe when considering faults in seismic hazard assessments? Are field geologists providing the relevant information for seismic hazard assessment? Are seismic hazard analysts interpreting field data appropriately? Is the full range of uncertainties associated with the characterization of faults correctly understood and propagated in the computations? How can fault-modellers contribute to a better representation of the long-term behaviour of fault-networks in seismic hazard studies? Providing answers to these questions is fundamental, in order to reduce the consequences of future earthquakes and improve the reliability of seismic hazard assessments. An informal working group was thus created at a meeting in Paris in November 2014, partly financed by the Institute of Radioprotection and Nuclear Safety, with the aim to motivate exchanges between field geologists, fault modellers and seismic hazard practitioners. A variety of approaches were presented at the meeting and a clear gap emerged between some field geologists, that are not necessarily familiar with probabilistic seismic hazard assessment methods and needs and practitioners that do not necessarily propagate the "full" uncertainty associated with the characterization of faults. The group thus decided to meet again a year later in Chieti (Italy), to share concepts and ideas through a specific exercise on a test case study. Some solutions emerged but many problems of seismic source characterizations with people working in the field as well as with people tackling models of interacting faults remained. Now, in Wien, we want to open the group and launch a call for the European community at large to contribute to the discussion. The 2016 EGU session Fault2SHA is motivated by such an urgency to increase the number of round tables on this topic and debate on the peculiarities of using faults in seismic hazard

  10. Effect of Mo microstructure on the critical volume fraction for conduction in Mo-alumina cermets

    Energy Technology Data Exchange (ETDEWEB)

    Kelso, J.F.; Higgins, R.R.; Krivda, F.J. [Alcoa Technical Center, Alcoa Center, Pennsylvania 15069 (United States)

    1997-03-01

    The microstructure of Mo in an alumina/frit matrix was found to be dependent on the initial partial sizes of the alumina and Mo powders, the glass content in the matrix ceramic, and the amount of moisture in the firing atmosphere. The Mo microstructure had a significant influence on the critical volume fraction for conductivity in these cermets. Coarser alumina powder, finer Mo powder, and higher glass content promoted coalescence of Mo into conductive networks at lower metal contents. Drier firing atmospheres produced a more coarsened Mo microstructure with a slight decrease in the amount of network contiguity, causing an increase in the amount required for electrical percolation. {copyright} {ital 1997 Materials Research Society.}

  11. Nature's polyoxometalate chemistry: X-ray structure of the Mo storage protein loaded with discrete polynuclear Mo-O clusters.

    Science.gov (United States)

    Kowalewski, Björn; Poppe, Juliane; Demmer, Ulrike; Warkentin, Eberhard; Dierks, Thomas; Ermler, Ulrich; Schneider, Klaus

    2012-06-13

    Some N(2)-fixing bacteria prolong the functionality of nitrogenase in molybdenum starvation by a special Mo storage protein (MoSto) that can store more than 100 Mo atoms. The presented 1.6 Å X-ray structure of MoSto from Azotobacter vinelandii reveals various discrete polyoxomolybdate clusters, three covalently and three noncovalently bound Mo(8), three Mo(5-7), and one Mo(3) clusters, and several low occupied, so far undefinable clusters, which are embedded in specific pockets inside a locked cage-shaped (αβ)(3) protein complex. The structurally identical Mo(8) clusters (three layers of two, four, and two MoO(n) octahedra) are distinguishable from the [Mo(8)O(26)](4-) cluster formed in acidic solutions by two displaced MoO(n) octahedra implicating three kinetically labile terminal ligands. Stabilization in the covalent Mo(8) cluster is achieved by Mo bonding to Hisα156-N(ε2) and Gluα129-O(ε1). The absence of covalent protein interactions in the noncovalent Mo(8) cluster is compensated by a more extended hydrogen-bond network involving three pronounced histidines. One displaced MoO(n) octahedron might serve as nucleation site for an inhomogeneous Mo(5-7) cluster largely surrounded by bulk solvent. In the Mo(3) cluster located on the 3-fold axis, the three accurately positioned His140-N(ε2) atoms of the α subunits coordinate to the Mo atoms. The formed polyoxomolybdate clusters of MoSto, not detectable in bulk solvent, are the result of an interplay between self- and protein-driven assembly processes that unite inorganic supramolecular and protein chemistry in a host-guest system. Template, nucleation/protection, and catalyst functions of the polypeptide as well as perspectives for designing new clusters are discussed.

  12. RANCANG BANGUN APLIKASI ANTIVIRUS KOMPUTER DENGAN MENGGUNAKAN METODE SECURE HASH ALGORITHM 1 (SHA1 DAN HEURISTIC STRING

    Directory of Open Access Journals (Sweden)

    I Gusti Made Panji Indrawinatha

    2016-12-01

    Full Text Available Virus komputer merupakan perangkat lunak berbahaya yang dapat merusak data dan menggandakan diri pada sistem komputer. Untuk mendeteksi dan membersihkan virus dari sistem komputer, maka dibuatlah aplikasi antivirus. Dalam mendeteksi berbagai jenis virus sebuah aplikasi antivirus biasanya menggunakan beberapa metode. Pada penelitian ini akan membahas perancangan sebuah aplikasi antivirus menggunakan metode Secure Hash Algorithm 1 (SHA1 dan heuristic string sebagai metode pendeteksian virus. Dari pengujian yang dilakukan diperoleh hasil dimana saat tidak menggunakan heuristic, antivirus hanya mendeteksi 12 file dari 34 file sample virus atau memiliki tingkat akurasi pendeteksian sebesar 35%. sedangkan saat menggunakan heuristic, antivirus berhasil mendeteksi 31 file dari 34 file sample virus atau memiliki tingkat akurasi pendeteksian sebesar 91%.

  13. Properties of Superconducting Mo, Mo2n and Trilayer Mo2n-Mo-Mo2n Thin Films

    Science.gov (United States)

    Barrentine, E. M.; Stevenson, T. R.; Brown, A. D.; Lowitz, A. E.; Noroozian, O.; U-Yen, K.; Eshan, N.; Hsieh, W. T.; Moseley, S. H.; Wollack, E. J.

    2014-01-01

    We present measurements of the properties of thin film superconducting Mo, Mo2N and Mo2N/Mo/Mo2N trilayers of interest for microwave kinetic inductance detector (MKID) applications. Using microwave resonator devices, we investigate the transition temperature, energy gaps, kinetic inductance, and internal quality factors of these materials. We present an Usadel-based interpretation of the trilayer transition temperature as a function of trilayer thicknesses, and a 2-gap interpretation to understand the change in kinetic inductance and internal resonance quality factor (Q) as a function of temperature.

  14. Application of the ReNuMa model in the Sha He river watershed: tools for watershed environmental management.

    Science.gov (United States)

    Sha, Jian; Liu, Min; Wang, Dong; Swaney, Dennis P; Wang, Yuqiu

    2013-07-30

    Models and related analytical methods are critical tools for use in modern watershed management. A modeling approach for quantifying the source apportionment of dissolved nitrogen (DN) and associated tools for examining the sensitivity and uncertainty of the model estimates were assessed for the Sha He River (SHR) watershed in China. The Regional Nutrient Management model (ReNuMa) was used to infer the primary sources of DN in the SHR watershed. This model is based on the Generalized Watershed Loading Functions (GWLF) and the Net Anthropogenic Nutrient Input (NANI) framework, modified to improve the characterization of subsurface hydrology and septic system loads. Hydrochemical processes of the SHR watershed, including streamflow, DN load fluxes, and corresponding DN concentration responses, were simulated following calibrations against observations of streamflow and DN fluxes. Uncertainty analyses were conducted with a Monte Carlo analysis to vary model parameters for assessing the associated variations in model outputs. The model performed accurately at the watershed scale and provided estimates of monthly streamflows and nutrient loads as well as DN source apportionments. The simulations identified the dominant contribution of agricultural land use and significant monthly variations. These results provide valuable support for science-based watershed management decisions and indicate the utility of ReNuMa for such applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. An herbal medicine, Go-sha-jinki-gan (GJG, increases muscle weight in severe muscle dystrophy model mice

    Directory of Open Access Journals (Sweden)

    Yusei Takemoto

    2017-12-01

    Full Text Available Go-sha-jinki-gan (GJG, a traditional Japanese herbal medicine has a clinical implication to alleviate age-related symptoms, especially in some motor disorders. However, the scientific evidence is limited, and there is a possibility to expand the medical application range of GJG. Using senescence-accelerated mice, our group showed that GJG exerted an effect to prevent sarcopenia, the aged-related loss of skeletal muscle. Because muscular dystrophy is characterized by a progressive loss of skeletal muscle, we examined the effects of GJG on a mouse model of muscular dystrophy. Using a newly established mouse model for Duchenne muscular dystrophy (DMD, DBA/2-mdx, we showed that GJG significantly increased the body and skeletal muscle weights in comparison to the control DBA/2-mdx mice, regardless of gender. The increased skeletal muscle mass resulted from an increment in the myofiber size, but not from the myofiber number. Both the skeletal muscle regenerative ability and the accumulation of fibrosis (the dystrophic pathology in GJG-fed DBA/2-mdx mice were comparable to those in control DBA/2-mdx mice, suggesting that the cellular target of GJG is myofibers, with no contribution from the muscle satellite cells neither in an direct nor in an indirect manner. Taken together, GJG increased the skeletal muscle mass in a mouse model of muscular dystrophy, in addition to our previously tested sarcopenia mouse model.

  16. Bruising caused by traditional Chinese massage therapy (ba sha) complicating the assessment of a case of fatal child abuse.

    Science.gov (United States)

    Li, Zhen; Huan, Zhang; Byard, Roger W

    2015-11-01

    Precise evaluation of bruises and patterned skin lesions in infants and children is an essential requirement in cases of potential abuse. Such injuries may be markers of more significant internal injuries and/or may be supportive of an assault rather than an accident. On occasion, however, unusual patterned skin lesions may be identified that have been inflicted as part of traditional therapeutic techniques. A five-year-old boy from a rural Chinese community is reported who died from ligature strangulation. In addition to bruises from abusive trauma he had a series of unusual patterned, often-paired, bruises over the anterior and posterior aspects of both shoulders, unrelated to the ligature mark. Upon further police inquiries it transpired that his grandmother and mother had been using traditional Chinese therapeutic massage or "ba sha" to treat an episode of vomiting. The term means "to pull out fever" and involves firm pinching of the skin between the thumb and index finger, often on the neck, chest or back. An awareness of the potential manifestations of traditional therapies is important in contemporary forensic practice so that injuries caused by these treatments are not confused with non-therapeutic inflicted injury. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  17. High performance Mo adsorbent PZC

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-10-01

    We have developed Mo adsorbents for natural Mo(n, {gamma}){sup 99}Mo-{sup 99m}Tc generator. Among them, we called the highest performance adsorbent PZC that could adsorb about 250 mg-Mo/g. In this report, we will show the structure, adsorption mechanism of Mo, and the other useful properties of PZC when you carry out the examination of Mo adsorption and elution of {sup 99m}Tc. (author)

  18. Prediction of Continuous Cooling Diagrams for the Precision Forged Tempering Steel 50CrMo4 by Means of Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Florian Nürnberger

    2009-01-01

    Full Text Available Quenching and tempering of precision forged components using their forging heat leads to reduced process energy and shortens the usual process chains. To design such a process, neither the isothermal transformation diagrams (TTT nor the continuous cooling transformation (CCT diagrams from literature can be used to predict microstructural transformations during quenching since the latter diagrams are significantly influenced by previous deformations and process-related high austenitising temperatures. For this reason, deformation CCT diagrams for several tempering steels from previous works have been investigated taking into consideration the process conditions of precision forging. Within the scope of the present work, these diagrams are used as input data for predicting microstructural transformations by means of artificial neural networks. Several artificial neural network structures have been examined using the commercial software MATLAB. Predictors have been established with satisfactory capabilities for predicting CCT diagrams for different degrees of deformation within the analyzed range of data.

  19. Changes in urinary Cu, Zn, and Se levels in cancer patients after treatment with Sha Shen Mai Men Dong Tang

    Directory of Open Access Journals (Sweden)

    Tung-Yuan Lai

    2016-04-01

    Full Text Available Sha Shen Mai Men Dong Tang (SMD-2; 沙參麥冬湯 shā shēn mài dōng tāng is a Chinese medicinal herb (CMH; 中草藥 zhōng cǎo yào used to treat symptoms associated with cancer therapy. The objective of this study was to assess the effect of SMD-2 on the levels of urinary copper (Cu, zinc (Zn, and selenium (Se in lung cancer patients and head and neck cancer patients receiving chemoradiotherapy. Forty-two head and neck cancer patients and 10 lung cancer patients participated in our clinical trial. Each patient received chemoradiotherapy for 4 weeks. In addition, each patient was treated with SMD-2 for 8 weeks, including 2 weeks prior to and after the chemoradiotherapy treatment. Comparison of urinary Cu, Zn, and Se levels and the ratios of Zn to Cu and Se to Cu at three time points in the two types of cancer were assessed using the generalized estimating equations (GEEs. After the patients received chemoradiotherapy for 4 weeks, SMD-2 treatment was found to be associated with a significant decrease in urinary Cu levels, whereas urinary Zn and Se levels increased significantly. In addition, the ratios of Zn to Cu and Se to Cu in the urine samples of these patients also increased significantly. Both the urinary Zn levels and the ratio of Zn to Cu in head and neck cancer patients were significantly higher than in lung cancer patients. Urinary Zn and Se levels and the ratios of Zn to Cu and Se to Cu, but not urinary Cu levels, increased significantly during and after treatment when assessed using the GEE model. The SMD-2 treatments significantly increased Zn and Se levels in the urine of head and neck cancer patients. Increased Zn and Se levels in urine strengthened immune system.

  20. MoEDAL expands

    CERN Multimedia

    Anaïs Schaeffer

    2011-01-01

    The MoEDAL collaboration deployed a test array of 18 plastic Nuclear Track Etch Detector (NTD) stacks – covering an area of 1 m2 – in the MoEDAL/VELO cavern at Point 8 of the LHC ring in November 2009. This small array was supplemented by a further 110 stacks this past January. The MoEDAL test array, which now covers an area of 8 m2, will reveal its secrets early in 2013. The full MoEDAL detector will be installed in the next long shutdown of the LHC in 2013.   View of the MoEDAL detectors installed at Point 8 of the LHC ring in January 2011. MoEDAL (Monopole and Exotics Detector At the LHC), the seventh LHC experiment, was approved by the CERN Research Board at the end of 2009. Its goal is to search for very specific exotics such as highly ionising massive stable (or pseudo-stable) particles with conventional electrical charge and magnetic monopoles. “The main LHC experiments are designed to detect conventionally charged particles, with conventional ionisation patte...

  1. Hydrodesulfurization of dibenzothiophene catalyzed by sulfided CoO-MoO/sub 3/. gamma. -Al/sub 2/O/sub 3/: the reaction network. [Dibenzothiophene

    Energy Technology Data Exchange (ETDEWEB)

    Houalla, M.; Nag, N.K.; Sapre, A.V.; Broderick, D.H.; Gates, B.C.

    1978-11-01

    Kinetic experiments in a high-pressure microreactor and a batch autoclave reactor elucidated the reaction network in the hydrodesulfurization of dibenzothiophene (a relatively unreactive compound in petroleum and coal-derived liquids), catalyzed by sulfided cobalt oxide/molybdenum trioxide/..gamma..-alumina at 573/sup 0/K and 102 atm. The predominant reaction was a direct sulfur extrusion, giving biphenyl and hydrogen sulfide; the biphenyl was subsequently hydrogenated slowly to give cyclohexylbenzene and then bicyclohexyl. Dibenzothiophene also underwent a primary hydrogenation reaction preceding sulfur removal, but it was about 1000 times slower than the sulfur extrusion reaction. The results showed that when methyl groups are present in the four and six positions of dibenzothiophene, the primary hydrogenation reaction is approximately as fast as the primary hydrodesulfurization reaction. Nickel and molybdenum or nickel and tungsten used instead of cobalt and molybdenum in the catalyst, or hydrogen sulfide in the reactant mixture, also favor hydrogenation relative to hydrodesulfurization.

  2. Advanced meet-in-the-middle preimage attacks: First results on full tiger, and improved results on MD4 and SHA-2

    DEFF Research Database (Denmark)

    Guo, Jian; Ling, San; Wang, Huaxiong

    2010-01-01

    We revisit narrow-pipe designs that are in practical use, and their security against preimage attacks. Our results are the best known preimage attacks on Tiger, MD4, and reduced SHA-2, with the result on Tiger being the first cryptanalytic shortcut attack on the full hash function. Our attacks runs...... in time 2188.8 for finding preimages, and 2188.2 for second-preimages. Both have memory requirement of order 28, which is much less than in any other recent preimage attacks on reduced Tiger. Using pre-computation techniques, the time complexity for finding a new preimage or second-preimage for MD4 can...

  3. MoDOT pavement preservation research program volume IV, pavement evaluation tools-data collection methods.

    Science.gov (United States)

    2015-10-01

    The overarching goal of the MoDOT Pavement Preservation Research Program, Task 3: Pavement Evaluation Tools Data : Collection Methods was to identify and evaluate methods to rapidly obtain network-level and project-level information relevant to :...

  4. Effect of molecular intercalation on the local structure of superconducting Nax(NH3)yMoSe2 system

    Science.gov (United States)

    Simonelli, L.; Paris, E.; Wakita, T.; Marini, C.; Terashima, K.; Miao, X.; Olszewski, W.; Ramanan, N.; Heinis, D.; Kubozono, Y.; Yokoya, T.; Saini, N. L.

    2017-12-01

    We have studied the local structure of layered Nax(NH3)yMoSe2 system by Mo K-edge extended X-ray absorption fine structure (EXAFS) measurements performed as a function of temperature. We find that molecular intercalation in MoSe2 largely affects the Mo-Se network while Mo-Mo seems to sustain small changes. The Einstein temperature (ΘE) of Mo-Mo distance hardly changes (∼264 K) indicating that bond strength of this distance remains unaffected by intercalation. On the other hand, Mo-Se distance suffers a softening, revealed by the decrease of ΘE from ∼364 K to ∼350 K. The results indicate that Na+ ion transported by NH3 molecules may enter between the two MoSe-layers resulting reduced Se-Se coupling. Therefore, increased hybridization between Se 4p and Mo 4d orbitals due to inter-layer disorder is the likely reason of metallicity in intercalated MoSe2 and superconductivity at low temperature.

  5. Preparation of MoB and MoB-MoSi{sub 2} composites by combustion synthesis in SHS mode

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, C.L. [Department of Mechanical and Automation Engineering, Da-Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Changhua 51505, Taiwan (China)]. E-mail: clyeh@mail.dyu.edu.tw; Hsu, W.S. [Department of Mechanical and Automation Engineering, Da-Yeh University, 112 Shan-Jiau Road, Da-Tsuen, Changhua 51505, Taiwan (China)

    2007-08-16

    Combustion synthesis in the mode of self-propagating high-temperature synthesis (SHS) was carried out in the Mo-B and Mo-B-Si systems for the preparation of molybdenum boride MoB and the composite of MoB-MoSi{sub 2} from elemental powder compacts. Under a preheating temperature above 150 deg. C , the reaction of Mo with boron in the sample compact of Mo:B = 1:1 is characterized by a planar combustion front propagating in a self-sustaining and steady manner. As the preheating temperature or sample compaction density increased, combustion temperature was found to increase and the propagation rate of the combustion front was correspondingly enhanced. Moreover, the XRD analysis provides evidence of yielding nearly single-phase {alpha}-MoB from the Mo-B sample at equiatomic stoichiometry. In the synthesis of MoB-MoSi{sub 2} composites, the starting stoichiometry of the Mo-B-Si powder compact was varied so as to produce the final composites containing 20-80 mol% MoB. It was also found the increase of flame-front velocity and combustion temperature with increasing MoB content formed in the composite. The composition analysis by XRD shows excellent conversion from the Mo-B-Si powder compact to the MoB-MoSi{sub 2} composite through the SHS reaction; that is, in addition to a small amount of Mo{sub 5}Si{sub 3}, the as-synthesized composite is composed entirely of MoB and MoSi{sub 2}.

  6. The evaluation of marine traffic noise and its effect on the Chinese White Dolphins in Sha Chau and Lung Kwu Chau Marine Park, Hong Kong

    Science.gov (United States)

    Chan, T.

    2016-12-01

    The Hong Kong International Airport (HKIA) handles a large amount of air traffic, at 68.5 million passengers per year (approx. 40.1 million flights per year). Given that flight demand is forecast to reach 97 million passengers per year (approx 60.2 million flights per year) by 2030, the HKIA must optimise runway capacity in order to meet growing demand. Hence, the Airport Authority Hong Kong (AAHK) has put forward a proposal to expand the airport into a three-runway system by building a third runway. However, this presents many environmental constraints. These include major impacts on marine ecology; especially the Chinese White Dolphins (Sousa chinensis) that live around the Sha Chau and Lung Kwu Chau Marine Park north to the airport. Due to that the third runway will reclaim approximately 650 hectares of the se so re-routing of speed boats and ferries has been planned. This includes one route that passes through the marine nursery inside the park. This indirectly causes noise pollution that will affect marine life. Since dolphins rely on echolocation (often discerned by a "click" sound) to communicate and navigate, increasing marine traffic (re-routing) causes obscuring noises and acoustic communication interfering with echolocation, as well as collisions which lead to physical injuries. Underwater construction works involving techniques such as percussive piling may interfere with the dolphins' echolocation capability. The data has been collected using a hydrophone by observing the noise frequency changes within the marine park. The noises come from a number of sources, including fishing boats, and speed boats, krill and around 20 estuarine fish species. The evaluation of four years (2013-2016) has shown that noise pollution is increasing (as indicated by the increase of frequencies around 100 125 kHz) and that it has caused disruption in regular dolphin movement (irregular clicking sequence) .

  7. ATP and MO25? Regulate the Conformational State of the STRAD? Pseudokinase and Activation of the LKB1 Tumour Suppressor

    OpenAIRE

    Zeqiraj, Elton; Filippi, Beatrice Maria; Goldie, Simon; Navratilova, Iva; Boudeau, J?r?me; Deak, Maria; Alessi, Dario R.; van Aalten, Daan M. F.

    2009-01-01

    Pseudokinases lack essential residues for kinase activity, yet are emerging as important regulators of signal transduction networks. The pseudokinase STRAD activates the LKB1 tumour suppressor by forming a heterotrimeric complex with LKB1 and the scaffolding protein MO25. Here, we describe the structure of STRADalpha in complex with MO25alpha. The structure reveals an intricate web of interactions between STRADalpha and MO25alpha involving the alphaC-helix of STRADalpha, reminiscent of the me...

  8. Mo-Si alloy development

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.T.; Heatherly, L.; Wright, J.L. [Oak Ridge National Lab., TN (United States)

    1996-06-01

    The objective of this task is to develop new-generation corrosion-resistant Mo-Si intermetallic alloys as hot components in advanced fossil energy conversion and combustion systems. The initial effort is devoted to Mo{sub 5}-Si{sub 3}-base (MSB) alloys containing boron additions. Three MSB alloys based on Mo-10.5Si-1.1B (wt %), weighing 1500 g were prepared by hot pressing of elemental and alloy powders at temperatures to 1600{degrees}C in vacuum. Microporosities and glassy-phase (probably silicate phases) formations are identified as the major concerns for preparation of MSB alloys by powder metallurgy. Suggestions are made to alleviate the problems of material processing.

  9. Dipole strength distribution below the giant dipole resonance in {sup 92}Mo, {sup 98}Mo and {sup 100}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Rusev, G.Y.

    2006-07-01

    Investigations of the dipole-strength distributions in {sup 92}Mo, {sup 98}Mo and {sup 100}Mo were carried out by means of the method of nuclear resonance fluorescence. The low-lying excitations in the nuclides {sup 92}Mo, {sup 98}Mo and {sup 100}Mo have been studied in photon-scattering experiments at an electron energy of 6 MeV at the ELBE accelerator and at electron energies from 3.2 to 3.8 MeV at the Dynamitron accelerator. Five levels were observed in {sup 92}Mo. Five levels in {sup 98}Mo and 14 in {sup 100}Mo were identified for the first time in the energy range from 2 to 4 MeV. Dipole-strength distributions up to the neutron-separation energies in the nuclides {sup 92}Mo, {sup 98}Mo and {sup 100}Mo have been investigated at the ELBE accelerator. Because of the possible observation of transitions in the neighboring nuclei produced via ({gamma},n) reaction, additional measurements at electron energies of 8.4 and 7.8 MeV, below the neutron-separation energy, were performed on {sup 98}Mo and {sup 100}Mo, respectively. The number of transitions assigned to {sup 92}Mo, {sup 98}Mo and {sup 100}Mo is 340, 485 and 499, respectively, the main part of them being dipole transitions. Statistical properties of the observed transitions are obtained. The continuum contains the ground-state transitions as well as the branching transitions to the low-lying levels and the subsequent deexcitations of these levels. (orig.)

  10. Prevalence of major depressive disorder and minor depressive disorder in an elderly Korean population: results from the Korean Longitudinal Study on Health and Aging (KLoSHA).

    Science.gov (United States)

    Park, Joon Hyuk; Lee, Jung Jae; Lee, Seok Bum; Huh, Yoonseok; Choi, Eun Ae; Youn, Jong Choul; Jhoo, Jin Hyeong; Kim, Jin Sun; Woo, Jong Inn; Kim, Ki Woong

    2010-09-01

    We investigated the prevalence, risk factors and impact of major depressive disorder (MDD) and minor depressive disorder (MnDD) in a randomly selected community-dwelling Korean elderly population. This study was conducted as a part of the Korean Longitudinal Study on Health and Aging (KLoSHA). A study population of 1118 Korean elders was randomly sampled from residents of Seongnam, Korea aged 65 years or older. Standardized face-to-face interviews and neurological and physical examinations were conducted on 714 respondents using the Korean version of Mini International Neuropsychiatric Interview. MDD was diagnosed according to the DSM-IV criteria, and MnDD according to research criteria proposed in Appendix B of the DSM-IV criteria. Age-, gender- and education-standardized prevalence rates in Korean elders aged 65 years or older were estimated as 5.37% (95% CI=3.72-7.03) for MDD, 5.52% (95% CI=3.84-7.19) for MnDD, and 10.89% (95% CI=8.60-13.17) for overall late-life depression (LLD). A prior MDD episode (OR=3.07, 95% CI=1.38-6.82 in MDD, OR=3.44, 95% CI=1.49-7.94 in MnDD), female gender (OR=3.55, 95% CI=1.53-8.24 in MDD, OR=2.68, 95% CI=1.19-6.04 in MnDD) and history of stroke or TIA (OR=3.45, 95% CI=1.62-7.35 in MDD, OR=2.95, 95% CI=1.34-6.52 in MnDD) were associated with the risks of both MDD and MnDD. Lack of formal education (OR=2.75, 95% CI=1.30-5.85) and low income (OR=2.83, 95% CI=1.02-7.88) were associated with the risk of MDD only. Quality of life (QOL) of the MDD and MnDD patients was worse than that of non-depressed elders (Pelders and impacted QOL as MDD did. MnDD patients may increase in the future with accelerated population aging and westernization of lifestyle in Korea. 2010 Elsevier B.V. All rights reserved.

  11. Measurement of target and double-spin asymmetries for the e<mo>→>p<mo>→mo><mo>→mo>eπ<mo>+mo><mo>(n)> reaction in the nucleon resonance region at low Q2

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, X.; Adhikari, K. P.; Bosted, P.; Deur, A.; Drozdov, V.; El Fassi, L.; Kang, Hyekoo; Kovacs, K.; Kuhn, S.; Long, E.; Phillips, S. K.; Ripani, M.; Slifer, K.; Smith, L. C.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Asryan, G.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chen, J. -P.; Chetry, T.; Choi, Seonho; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Crede, V.; D' Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Djalali, C.; Dodge, G. E.; Dupre, R.; Egiyan, H.; El Alaoui, A.; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Fersch, R.; Filippi, A.; Fleming, J. A.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Golovach, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Guo, L.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Kubarovsky, V.; Lanza, L.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Pisano, S.; Pogorelko, O.; Price, J. W.; Puckett, A. J. R.; Raue, B. A.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zonta, I.

    2016-10-01

    We report measurements of target- and double-spin asymmetries for the exclusive channel e<mo>→>p<mo>→mo><mo>→mo>eπ<mo>+mo><mo>(n)> in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries were extracted from data obtained using a longitudinally polarized NH3 target and a longitudinally polarized electron beam with energies 1.1, 1.3, 2.0, 2.3, and 3.0 GeV. The new results are consistent with previous CLAS publications but are extended to a low Q2 range from 0.0065 to 0.35 (GeV/c)2. The Q2 access was made possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low as 6 degrees. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis prediction from SAID, and the dynamic model DMT. In many kinematic regions our results, in particular results on the target asymmetry, help to constrain the polarization-dependent components of these models.

  12. Optimization of the Processing of Mo Disks

    Energy Technology Data Exchange (ETDEWEB)

    Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States); Stepinski, Dominique [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, Vakhtang [Argonne National Lab. (ANL), Argonne, IL (United States); Harvey, James [NorthStar Medical Technologies, LLC, Madison, WI (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    The objective of this work is to decrease the processing time for irradiated disks of enriched Mo for the production of 99Mo. Results are given for the dissolution of nonirradiated Mo disks, optimization of the process for large-scale dissolution of sintered disks, optimization of the removal of the main side products (Zr and Nb) from dissolved targets, and dissolution of irradiated Mo disks.

  13. Measurement and Estimation of the 99Mo Production Yield by 100Mo(n,2n)99Mo

    Science.gov (United States)

    Minato, Futoshi; Tsukada, Kazuaki; Sato, Nozomi; Watanabe, Satoshi; Saeki, Hideya; Kawabata, Masako; Hashimoto, Shintaro; Nagai, Yasuki

    2017-11-01

    We, for the first time, measured the yield of 99Mo, the mother nuclide of 99mTc used in nuclear medicine diagnostic procedures, produced by the 100Mo(n,2n)99Mo reaction with accelerator neutrons. The neutrons with a continuous energy spectrum from the thermal energy up to about 40 MeV were provided by the C(d,n) reaction with 40 MeV deuteron beams. It was proved that the 99Mo yield agrees with that estimated by using the latest data on neutrons from the C(d,n) reaction and the evaluated cross section of the 100Mo(n,2n)99Mo reaction given in the Japanese Evaluated Nuclear Data Library. On the basis of the agreement, a systematic calculation was carried out to search for an optimum condition that enables us to produce as much 99Mo as possible with a good 99Mo/100Mo value from an economical point of view. The calculated 99Mo yield from a 150 g 100MoO3 sample indicated that about 30% of the demand for 99Mo in Japan can be met with a single accelerator capable of 40 MeV, 2 mA deuteron beams. Here, by referring to an existing 18F-fluorodeoxyglucose (FDG) distribution system we assumed that 99mTc radiopharmaceuticals formed after separating 99mTc from 99Mo can be delivered to hospitals from a radiopharmaceutical company within 6 h. The elution of 99mTc from 99Mo twice a day would meet about 50% of the demand for 99Mo.

  14. Hierarchical Ni-Mo-S nanosheets on carbon fiber cloth: A flexible electrode for efficient hydrogen generation in neutral electrolyte.

    Science.gov (United States)

    Miao, Jianwei; Xiao, Fang-Xing; Yang, Hong Bin; Khoo, Si Yun; Chen, Jiazang; Fan, Zhanxi; Hsu, Ying-Ya; Chen, Hao Ming; Zhang, Hua; Liu, Bin

    2015-08-01

    A unique functional electrode made of hierarchal Ni-Mo-S nanosheets with abundant exposed edges anchored on conductive and flexible carbon fiber cloth, referred to as Ni-Mo-S/C, has been developed through a facile biomolecule-assisted hydrothermal method. The incorporation of Ni atoms in Mo-S plays a crucial role in tuning its intrinsic catalytic property by creating substantial defect sites as well as modifying the morphology of Ni-Mo-S network at atomic scale, resulting in an impressive enhancement in the catalytic activity. The Ni-Mo-S/C electrode exhibits a large cathodic current and a low onset potential for hydrogen evolution reaction in neutral electrolyte (pH ~7), for example, current density of 10 mA/cm(2) at a very small overpotential of 200 mV. Furthermore, the Ni-Mo-S/C electrode has excellent electrocatalytic stability over an extended period, much better than those of MoS2/C and Pt plate electrodes. Scanning and transmission electron microscopy, Raman spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and x-ray absorption spectroscopy were used to understand the formation process and electrocatalytic properties of Ni-Mo-S/C. The intuitive comparison test was designed to reveal the superior gas-evolving profile of Ni-Mo-S/C over that of MoS2/C, and a laboratory-scale hydrogen generator was further assembled to demonstrate its potential application in practical appliances.

  15. Phase II evaluation of waste concrete road materials for use in oyster aquaculture - field test, [research summary].

    Science.gov (United States)

    2015-02-01

    The Maryland State Highway Administration (SHA) has a commitment to : maintaining at least 84 percent of the SHA pavement network in acceptable : overall condition. The SHA also intends to increase the use of recycled : materials and to use products ...

  16. Evaluation of waste concrete road materials for use in oyster aquaculture : [research summary].

    Science.gov (United States)

    2013-02-01

    The Maryland State Highway Administration (SHA) has a commitment to : maintaining at least 84 percent of the SHA pavement network in : acceptable overall condition. The SHA also intends to increase the use of : recycled materials and to use products ...

  17. Measurement of the Single Top Quark Production Cross Section and <mo stretchy='false'>|mo>Vtb<mo stretchy='false'>|mo> in Events with One Charged Lepton, Large Missing Transverse Energy, and Jets at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, T.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Auerbach, B.; Aurisano, A.; Azfar, F.; Badgett, W.; Bae, T.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauce, M.; Bedeschi, F.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Bland, K. R.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brigliadori, L.; Bromberg, C.; Brucken, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Bussey, P.; Butti, P.; Buzatu, A.; Calamba, A.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cerri, A.; Cerrito, L.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Chokheli, D.; Clark, A.; Clarke, C.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; d’Ascenzo, N.; Datta, M.; de Barbaro, P.; Demortier, L.; Deninno, M.; D’Errico, M.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Dittmann, J. R.; Donati, S.; D’Onofrio, M.; Dorigo, M.; Driutti, A.; Ebina, K.; Edgar, R.; Elagin, A.; Erbacher, R.; Errede, S.; Esham, B.; Farrington, S.; Fernández Ramos, J. P.; Field, R.; Flanagan, G.; Forrest, R.; Franklin, M.; Freeman, J. C.; Frisch, H.; Funakoshi, Y.; Galloni, C.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Giokaris, N.; Giromini, P.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grosso-Pilcher, C.; Group, R. C.; Guimaraes da Costa, J.; Hahn, S. R.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, M.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hays, C.; Heinrich, J.; Herndon, M.; Hirschbuehl, D.; Hocker, A.; Hong, Z.; Hopkins, W.; Hou, S.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Kasmi, A.; Kato, Y.; Ketchum, W.; Keung, J.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. H.; Kim, S. B.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Knoepfel, K.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kurata, M.; Laasanen, A. T.; Lammel, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lee, H. S.; Lee, J. S.; Leo, S.; Leone, S.; Lewis, J. D.; Limosani, A.; Lipeles, E.; Lister, A.; Liu, H.; Liu, Q.; Liu, T.; Lockwitz, S.; Loginov, A.; Lucchesi, D.; Lucà, A.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lys, J.; Lysak, R.; Madrak, R.; Maestro, P.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Marchese, L.; Margaroli, F.; Marino, P.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Mesropian, C.; Miao, T.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakano, I.; Napier, A.; Nett, J.; Neu, C.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Ortolan, L.; Pagliarone, C.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parker, W.; Pauletta, G.; Paulini, M.; Paus, C.; Phillips, T. J.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pondrom, L.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ristori, L.; Robson, A.; Rodriguez, T.; Rolli, S.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sakumoto, W. K.; Sakurai, Y.; Santi, L.; Sato, K.; Saveliev, V.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, E. E.; Schwarz, T.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Semenov, A.; Sforza, F.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simonenko, A.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Song, H.; Sorin, V.; St. Denis, R.; Stancari, M.; Stentz, D.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Ukegawa, F.; Uozumi, S.; Vázquez, F.; Velev, G.; Vellidis, C.; Vernieri, C.; Vidal, M.; Vilar, R.; Vizán, J.; Vogel, M.; Volpi, G.; Wagner, P.; Wallny, R.; Wang, S. M.; Waters, D.; Wester, W. C.; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, H.; Wright, T.; Wu, X.; Wu, Z.; Yamamoto, K.; Yamato, D.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W. -M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Zanetti, A. M.; Zeng, Y.; Zhou, C.; Zucchelli, S.

    2014-12-31

    We report a measurement of single top quark production in proton-antiproton collisions at a center-of-mass energy of smo>=>1.96 TeV using a data set corresponding to 7.5 fbmo>->1 of integrated luminosity collected by the Collider Detector at Fermilab. We select events consistent with the single top quark decay process tmo stretchy="false">→mo>Wbmo stretchy="false">→mo>mo>ℓmo>νb by requiring the presence of an electron or muon, a large imbalance of transverse momentum indicating the presence of a neutrino, and two or three jets including at least one originating from a bottom quark. An artificial neural network is used to discriminate the signal from backgrounds. We measure a single top quark production cross section of 3.04mo>->0.53mo>+>0.57 pb and set a lower limit on the magnitude of the coupling between the top quark and bottom quark mo stretchy="false">|mo>

  18. MoS2/MoOx-Nanostructure-Decorated Activated Carbon Cloth for Enhanced Supercapacitor Performance.

    Science.gov (United States)

    Sari, Fitri Nur Indah; Ting, Jyh-Ming

    2018-01-04

    MoS 2 /MoO x nanostructures were grown on activated carbon cloth through a facile one-step microwave-assisted hydrothermal method. The growth of MoS 2 /MoO x on activated carbon cloth creates a unique structure that favors ion intercalation. The conductive activated carbon cloth, MoO 3-x , and monoclinic MoO 2 provide fast electron transport, whereas the MoS 2 nanosheets/MoO 3-x nanoparticles structure improves the capacitance. As a result, MoS 2 /MoO x -nanostructure-decorated activated carbon cloth shows a high specific capacitance of 230 F g -1 at a scan rate of 5 mV s -1 with a low contact resistance of approximately 1.91 Ω. Moreover, the activated carbon cloth acts as a template for the growth of a perpendicular MoS 2 layer, which gives an excellent utilization rate of the active MoS 2 /MoO x material. We also demonstrate that the MoS 2 /MoO x /activated carbon cloth nanocomposite shows excellent electrochemical stability with retention up to 128 % after 1500 cycles. Finally, we show the use of a microwave-assisted hydrothermal method for the synthesis of the MoS 2 /MoO x /activated carbon cloth nanocomposite as an alternative and clean route to improve the kinetics of the intercalation redox reaction. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Measurement of excitation functions for the {sup nat}Mo(d,x){sup 99}Mo and {sup nat}Mo(p,x){sup 99}Mo reactions

    Energy Technology Data Exchange (ETDEWEB)

    Chodash, P., E-mail: chodash2@berkeley.edu [University of California, Berkeley, Department of Nuclear Engineering, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720 (United States); Angell, C.T. [University of California, Berkeley, Department of Nuclear Engineering, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720 (United States); Benitez, J. [University of California, Berkeley, Department of Nuclear Engineering, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720 (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division (United States); Norman, E.B. [University of California, Berkeley, Department of Nuclear Engineering, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720 (United States); Lawrence Berkeley National Laboratory, Nuclear Science Division (United States); Lawrence Livermore National Laboratory (United States); Pedretti, M. [Lawrence Livermore National Laboratory (United States); Shugart, H. [Department of Physics, University of California, Berkeley (United States); Swanberg, E.; Yee, R. [University of California, Berkeley, Department of Nuclear Engineering, 4155 Etcheverry Hall, MC 1730, Berkeley, CA 94720 (United States); Lawrence Livermore National Laboratory (United States)

    2011-10-15

    The excitation functions for proton and deuteron induced reactions on natural molybdenum for the production of {sup 99}Mo were measured. The proton induced reaction was measured in the energy range of 11.3-49.6 MeV, and the deuteron induced reaction was measured in the energy range of 9.7-58.5 MeV. Both beams were generated by the 88'' cyclotron located at Lawrence Berkeley National Laboratory. The results are compared to previously published data. Thick target yields were obtained by direct measurement, in addition to being determined by integration of the measured cross sections. - Highlights: > Cross sections were measured using the stacked foil technique. > Cross sections were measured for the {sup nat}Mo(d,x){sup 99}Mo and {sup nat}Mo(p,x){sup 99}Mo reactions. > Thick target yields were determined for the {sup nat}Mo(d,x){sup 99}Mo reactions up to 59 MeV. > Thick target yields were determined for the {sup nat}Mo(p,x){sup 99}Mo reactions up to 50 MeV.

  20. Mo99 Production Plant Layout

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-25

    The NorthStar Medical Technologies 99Mo production facility configuration is envisioned to be 8 accelerator pairs irradiating 7 100Mo targets (one spare accelerator pair undergoing maintenance while the other 7 pairs are irradiating targets). The required shielding in every direction for the accelerators is initially estimated to be 10 feet of concrete. With the accelerator pairs on one (ground) level and spaced with the required shielding between adjacent pairs, the only practical path for target insertion and removal while minimizing floor space is vertical. The current scheme then requires a target vertical lift of nominally 10 feet through a shield stack. It is envisioned that the lift will be directly into a hot cell where an activated target can be removed from its holder and a new target attached and lowered. The hot cell is on a rail system so that a single hot cell can service all active target locations, as well as deliver the ready targets to the separations lab. On this rail system, coupled to the hot cell, will be a helium recovery and clean-up system. All helium coolant equipment is located on the upper level near to the target removal point.

  1. Edge termination of MoS2 and CoMoS catalyst particles

    DEFF Research Database (Denmark)

    Byskov, Line Sjolte; Nørskov, Jens Kehlet; Clausen, B. S.

    2000-01-01

    The edge termination of MoS2 and CoMoS catalyst particles is studied by density functional calculations. We show that for structures without vacancies Mo-terminated edges have the lowest edge energies. Creation of vacancies, which are believed to be active sites in these catalyst systems, leads...

  2. Spin freezing in the geometrically frustrated pyrochlore antiferromagnet Tb2Mo2O7

    DEFF Research Database (Denmark)

    Gaulin, B.D.; Reimers, J.N.; Mason, T.E.

    1992-01-01

    The magnetic metal ions in the cubic pyrochlore Tb2Mo2O7 form an infinite three-dimensional network of corner-sharing tetrahedra with a very high potential for frustration in the presence of antiferromagnetism. We have performed neutron scattering measurements which show short-range spatial corre...

  3. Mo(ve)ment-methodology

    DEFF Research Database (Denmark)

    Mørck, Line Lerche; Christian Celosse-Andersen, Martin

    2017-01-01

    of major identity formation and gang exit processes, done together with a former biker gang member, Martin, becoming a research apprentice and more academically reflective, while moving beyond gang involvement. The paper empirically exemplifies the mo(ve)ment methodology presenting and analyzing one...... experienced moment called “Sp(l)itting on the street”. It is a moment which captures multiple and double feelings of conflictual concerns, frustrations, anger, a new feeling of insecurity of masculinity, as well as the feeling of engagement and deep meaningfulness, when becoming a more reflective academic....... These various conflictual feelings, also includes a sense of being split into conflicting identities. The paper analyzes how such conflictual feelings also can be productive, and produce movements and change in identity formation through our social practice research analysis and joint venture. The analyzed...

  4. Characteristics of MoSe{sub 2} formation during rapid thermal processing of Mo-coated glass

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soobin; Koo, Jaseok; Kim, Sammi [School of Chemical Engineering, Yeungnam University, Gyeonsan, Gyeongbuk 712-749 (Korea, Republic of); Kim, Soo-Hyun [School of Materials Science and Engineering, Yeungnam University, Gyeonsan, Gyeongbuk 712-749 (Korea, Republic of); Cheon, Taehoon [Daegu Gyeongbuk Institute of Science and Technology, Daegu 711-873 (Korea, Republic of); Oh, Jong Seok; Kim, Suk Jin [AVACO Co., Ltd., Daegu 704-833 (Korea, Republic of); Kim, Woo Kyoung, E-mail: wkim@ynu.ac.kr [School of Chemical Engineering, Yeungnam University, Gyeonsan, Gyeongbuk 712-749 (Korea, Republic of)

    2013-05-01

    Multi-layered Mo, prepared using an in-line sputtering system, was selenized by reaction with Se vapor and thermal annealing of bilayer Mo/Se samples. In situ high-temperature X-ray diffraction analysis indicated that the phase evolution of the glass/Mo/Se sample during heat treatment was similar to that of the selenization of glass/Mo with Se vapor, except for crystallization of Se in the glass/Mo/Se sample. However, the MoSe{sub 2} layer formed from the selenization of the Mo layer by Se vapor preferentially grew perpendicularly to the Mo surface, whereas MoSe{sub 2} formed from the reaction of Mo with Se liquid showed random orientation. The detailed reaction pathways of the double-layer random-MoSe{sub 2}/vertical-MoSe{sub 2} formation from the Mo/Se bilayer sample were suggested on the basis of the several characterization results including X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy and selected-area electron diffraction patterns. - Highlights: ► The selenization of glass/Mo and glass/Mo/Se samples was investigated. ► The reaction of the Mo layer with Se vapor produced vertically oriented MoSe{sub 2}. ► Randomly oriented MoSe{sub 2} layer was formed from the reaction of Mo with liquid Se.

  5. AMORE Mo-99 Spike Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Youker, Amanda J. [Argonne National Lab. (ANL), Argonne, IL (United States); Krebs, John F. [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, Kevin J. [Argonne National Lab. (ANL), Argonne, IL (United States); Byrnes, James P. [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, David A [Argonne National Lab. (ANL), Argonne, IL (United States); Brossard, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States); Wesolowski, Kenneth [Argonne National Lab. (ANL), Argonne, IL (United States); Alford, Kurt [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-09-27

    With funding from the National Nuclear Security Administrations Material Management and Minimization Office, Argonne National Laboratory (Argonne) is providing technical assistance to help accelerate the U.S. production of Mo-99 using a non-highly enriched uranium (non-HEU) source. A potential Mo-99 production pathway is by accelerator-initiated fissioning in a subcritical uranyl sulfate solution containing low enriched uranium (LEU). As part of the Argonne development effort, we are undertaking the AMORE (Argonne Molybdenum Research Experiment) project, which is essentially a pilot facility for all phases of Mo-99 production, recovery, and purification. Production of Mo-99 and other fission products in the subcritical target solution is initiated by putting an electron beam on a depleted uranium (DU) target; the fast neutrons produced in the DU target are thermalized and lead to fissioning of U-235. At the end of irradiation, Mo is recovered from the target solution and separated from uranium and most of the fission products by using a titania column. The Mo is stripped from the column with an alkaline solution. After acidification of the Mo product solution from the recovery column, the Mo is concentrated (and further purified) in a second titania column. The strip solution from the concentration column is then purified with the LEU Modified Cintichem process. A full description of the process can be found elsewhere [1–3]. The initial commissioning steps for the AMORE project include performing a Mo-99 spike test with pH 1 sulfuric acid in the target vessel without a beam on the target to demonstrate the initial Mo separation-and-recovery process, followed by the concentration column process. All glovebox operations were tested with cold solutions prior to performing the Mo-99 spike tests. Two Mo-99 spike tests with pH 1 sulfuric acid have been performed to date. Figure 1 shows the flow diagram for the remotely operated Mo-recovery system for the AMORE project

  6. Impact of Reduced Graphene Oxide on MoS2 Grown by Sulfurization of Sputtered MoO3 and Mo Precursor Films (Postprint)

    Science.gov (United States)

    2016-05-26

    precursor films . In addition, they have studied the effects that reduced graphene oxide (rGO) has on MoS2 structure. Reports show that rGO increases MoS2...MoO3 and Mo precursor films . In addition, they have studied the effects that reduced graphene oxide (rGO) has on MoS2 structure. Reports show that rGO...rate of 75 sccm. TABLE I. List of thickness used for Mo and MoO3 precursor films . r indi - cated rGO was used during experiments. Sample (r-rGO) Precursor

  7. The excitation functions of (100)Mo(p,x)(99)Mo and (100)Mo(p,2n)(99m)Tc.

    Science.gov (United States)

    Manenti, Simone; Holzwarth, Uwe; Loriggiola, Massimo; Gini, Luigi; Esposito, Juan; Groppi, Flavia; Simonelli, Federica

    2014-12-01

    Proton-induced nuclear reactions for generation of (99)Mo and (99m)Tc radionuclides were investigated using the stacked-foil activation technique on 99.05% enriched (100)Mo targets at energies up to Ep=21MeV. Excitation functions of the reactions (100)Mo(p,x)(99)Mo and (100)Mo(p,2n)(99m)Tc have been measured. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Development of fission Mo-99 production technology

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Ho; Choung, W. M.; Lee, K. I. and others

    2001-05-01

    This R and D project is planed to supply domestic demands of Mo-99 through fission route, and consequently this project will be expected to rise up utilization of HANARO and KAERI's capability for marketing extension into domestic and oversea radiopharmaceutical market. HEU and LEU target types are decided and designed for fission Mo-99 production in domestic. Experimental study of target fabrication technology was performed and developed processing equipments. And conceptual design of target loading/unloading in/from HANARO device are performed. Tracer test of Mo-99 separation and purification process was performed, test results reach to Mo-99 recovery yield above 80% and decontamination factor above 1600. Combined Mo-99 separation and purification process was decided for hot test scheduled from next year, and performance test was performed. Conceptual design for modification of existing hot cell for fission Mo-99 production facility was performed and will be used for detail design. Assumption for the comparison of LEU and HEU target in fission Mo-99 production process were suggested and compared of merits and demerits in view of fabrication technology and economy feasibility.

  9. Activating and tuning basal planes of MoO₂, MoS₂, and MoSe₂ for hydrogen evolution reaction.

    Science.gov (United States)

    Lin, Shi-Hsin; Kuo, Jer-Lai

    2015-11-21

    We investigated the defected two-dimensional materials MoX2 (X = O, S, Se) for hydrogen evolution reaction by first principles calculations. While the basal plane is inert for pristine MoX2, we found that the defected MoX2 can adsorb hydrogen atoms at defect sites, with appropriate adsorption energies for hydrogen evolution. By analyzing density of states and charge density, we showed that a dangling bond state slightly below the Fermi energy emerges when a defect is created. We proposed that this state is responsible for hybridizing with the hydrogen atom 1s state and hence the adsorption. Knowing the mechanism, we further considered tuning the reaction using adatoms (several first-row transition metals, B, C, N, O). We found that C and O adatoms can make defected MoX2 ideal for hydrogen evolution at higher defect levels (H coverage).

  10. Nd2[MoC2] and RE2[WC2], RE=Ce, Pr, Nd: New carbometalates with Pr2[MoC2] structure type

    Directory of Open Access Journals (Sweden)

    Enkhtsetseg Dashjav, Yurii Prots, Guido Kreiner, Walter Schnelle, Frank R. Wagner and Rüdiger Kniep

    2007-01-01

    Full Text Available Four new ternary rare-earth-metal carbometalates, Nd2[MoC2] and RE2[WC2] with RE=Ce, Pr, Nd, have been synthesized by argon arc melting and subsequent heat treatment at 1170 K for 30 days. They crystallize with the Pr2[MoC2] structure type with isolated C4− species and are typical carbometalates with (i low metal-to-carbon ratio, (ii tetrahedral coordination of the transition metals (T by carbon, and (iii a polyanionic network ∞2[(TC26-]. According to resistivity measurements the compounds are bad metals. Volume chemistry and magnetic susceptibility measurements indicate Pr3+, Nd3+, and Ce4+ species, respectively. In the latter case, the additional electron is not transferred to the polyanionic network, instead it mainly populates the Ce partial structure.

  11. Encryption for confidentiality of the network and influence of this to the quality of streaming video through network

    Science.gov (United States)

    Sevcik, L.; Uhrin, D.; Frnda, J.; Voznak, M.; Toral-Cruz, Homer; Mikulec, M.; Jakovlev, Sergej

    2015-05-01

    Nowadays, the interest in real-time services, like audio and video, is growing. These services are mostly transmitted over packet networks, which are based on IP protocol. It leads to analyses of these services and their behavior in such networks which are becoming more frequent. Video has become the significant part of all data traffic sent via IP networks. In general, a video service is one-way service (except e.g. video calls) and network delay is not such an important factor as in a voice service. Dominant network factors that influence the final video quality are especially packet loss, delay variation and the capacity of the transmission links. Analysis of video quality concentrates on the resistance of video codecs to packet loss in the network, which causes artefacts in the video. IPsec provides confidentiality in terms of safety, integrity and non-repudiation (using HMAC-SHA1 and 3DES encryption for confidentiality and AES in CBC mode) with an authentication header and ESP (Encapsulating Security Payload). The paper brings a detailed view of the performance of video streaming over an IP-based network. We compared quality of video with packet loss and encryption as well. The measured results demonstrated the relation between the video codec type and bitrate to the final video quality.

  12. Explorations of new phases in the Ga(III)/In(III)-Mo(VI)-Se(IV)/Te(IV)-O systems.

    Science.gov (United States)

    Kong, Fang; Hu, Chun-Li; Hu, Ting; Zhou, Yong; Mao, Jiang-Gao

    2009-07-07

    Systematic explorations of new phases in the Ga(III)/In(III)-Mo(VI)-Se(IV)/Te(IV)-O systems by hydrothermal syntheses or solid-state reactions at high-temperature led to four new quaternary compounds, namely, Ga(2)MoQ(2)O(10) (Q = Se, Te), In(2)Mo(2)Se(2)O(13)(H(2)O) and In(2)MoTe(2)O(10). Ga(2)MoQ(2)O(10) (Q = Se, Te) are isostructural and their structures feature a 3D network of gallium selenite/tellurite with 12-member ring tunnels along b-axis, the distorted MoO(6) octahedra are attached on the wall of the above tunnels. The structure of In(2)Mo(2)Se(2)O(13)(H(2)O) features a new pillared-layered architecture composed of 2D indium(III) selenite layers that are interconnected by Mo(2)O(10) dimers, forming 8-membered ring tunnels along the b-axis. The structure of In(2)MoTe(2)O(10) features a 2D indium oxide layer formed by corner- and edge-sharing InO(6) and InO(7) polyhedra with MoO(4) tetrahedra and TeO(n) (n = 4, 5) polyhedra hanging on both sides of the layer, there are weak interlayer Te-O bonds of 2.512 A. Results of optical diffuse reflectance spectrum measurements indicate that all four compounds are insulators, which are in agreement with results of band structure calculations based on DFT methods.

  13. Phase transformations in Mo-doped FINEMETs

    Energy Technology Data Exchange (ETDEWEB)

    Silveyra, Josefina M., E-mail: jsilveyra@fi.uba.a [Lab. de Solidos Amorfos, INTECIN, FIUBA-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina); Illekova, Emilia; Svec, Peter; Janickovic, Dusan [Institute of Physics SAS, Dubravska cesta 9, 845 11 Bratislava (Slovakia); Rosales-Rivera, Andres [Laboratorio de Magnetismo y Materiales Avanzados, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Colombia, Manizales (Colombia); Cremaschi, Victoria J. [Lab. de Solidos Amorfos, INTECIN, FIUBA-CONICET, Paseo Colon 850, (C1063ACV) Buenos Aires (Argentina)

    2010-06-15

    In this paper, the phase transformations occurring during the crystallization process of FINEMETs in which Nb has been gradually replaced by Mo have been studied by a variety of techniques including DSC, DTA, TGA, XRD and TEM. The thermal stability of the alloy was deteriorated as a consequence of Mo's smaller atomic size. The gradual replacement of Nb by Mo reduced the onset temperature of Fe-Si and of the borides. The Curie temperature of the amorphous phase slightly decreased from 594 K for x=0 to 587 K for x=3. The borides compounds Fe{sub 2}B and Fe{sub 23}B{sub 6} as well as the (Nb,Mo){sub 5}Si{sub 3} phase were found to precipitate in the second and third crystallization.

  14. Floodplain Mapping Submission for Oregon County, MO

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping study deliverables depict and quantify the flood risks for Oregon County, MO. The City of Thayer and the Missouri State Emergency Management...

  15. PRoMoTo 2013 proceedings

    OpenAIRE

    Bishop, Judith; Tillmann, Nikolai; Puder, Arno; Naik, Vinayak

    2013-01-01

    Programming for Mobile and Touch (PRoMoTo'13) was held at the 2013 ACM SIGPLAN conference on Systems, Programming, Languages and Applications (SPLASH 2013), October 2013 in Indianapolis, USA. Submissions for this event were invited in the general area of mobile and touch-oriented programming languages and programming environments, and teaching of programming for mobile devices. These are proceedings of the PRoMoTo'13.

  16. A Bayesian network model for predicting aquatic toxicity mode of action using two dimensional theoretical molecular descriptors

    Science.gov (United States)

    The mode of toxic action (MoA) has been recognized as a key determinant of chemical toxicity, but development of predictive MoA classification models in aquatic toxicology has been limited. We developed a Bayesian network model to classify aquatic toxicity MoA using a recently pu...

  17. Un caballero español en Isfahán. La embajada de Don García de Silva y Figueroa al sha Abbás el Grande (1614-1624

    Directory of Open Access Journals (Sweden)

    Córdoba, Joaquín Mª

    2005-04-01

    Full Text Available Uno de los libros más interesantes de los escritos por viajeros europeos a Oriente se debe a un español, Don García de Silva y Figueroa, embajador de Felipe III ante el sha Abbás el Grande de Irán, Pero como la muerte le sobrevino en su viaje de vuelta a España, impidiéndole publicar sus notas y recuerdos, lo cierto es que hasta comienzos del siglo XX no sería publicado su manuscrito completo en nuestro país. Desde entonces sin embargo, el valor de su figura y su obra no han hecho sino crecer. Además de la descripción apasionante que Don García hizo de los paisajes y pueblos por los que anduvo, su libro también supone la primera identificación cierta de Persépolis, y la primera propuesta de los signos cuneiformes como escritura de los antiguos.…

  18. Attapulgite-CeO2/MoS2 ternary nanocomposite for photocatalytic oxidative desulfurization

    Science.gov (United States)

    Li, Xiazhang; Zhang, Zuosong; Yao, Chao; Lu, Xiaowang; Zhao, Xiaobing; Ni, Chaoying

    2016-02-01

    Novel attapulgite(ATP)-CeO2/MoS2 ternary nanocomposites were synthesized by microwave assisted assembly method. The structures of the nanocomposites were characterized by XRD, FT-IR, UV-vis, XPS and in situ TEM. The photocatalytic activities of ATP-CeO2/MoS2 composites were investigated by degradating dibenzothiophene (DBT) in gasoline under visible light irradiation. The effect of the mass ratio of CeO2 to MoS2 on photocatalytic activity was investigated. The results indicate that the three-dimensional network structure is firmly constructed by ATP skeleton, CeO2 particles and MoS2 nanosheet which effectively increase the surface area of the composites and promote the separation of electrons and holes by resulting electronic transmission channels of multi-channel in space. The degradation rate of DBT can reach 95% under 3 h irradiation when the mass ratio of CeO2/MoS2 is 4/10. A plausible mechanism for the photocatalytic oxidative desulfurization of this nanocomposite is put forward.

  19. A column material and a method for adsorbing Mo-99 in a 99Mo/99m Tc generator

    NARCIS (Netherlands)

    Bode, P.; Denkova, A.G.; Steinebach, O.M.; Terpstra, B.E.; Wolterbeek, H.T.

    2013-01-01

    A column material and a method for adsorbing Mo-99 in a 99Mo/ 99m Tc generator Abstract The invention relates to a column material for adsorbing Mo-99 in a 99 Mo/ 99m Tc generator, said column material (4) comprising a mesoporous MSU- X Al2O3 and/or TUD1-Al material. Preferably, a pore size of the

  20. Impact of reduced graphene oxide on MoS{sub 2} grown by sulfurization of sputtered MoO{sub 3} and Mo precursor films

    Energy Technology Data Exchange (ETDEWEB)

    Pacley, Shanee, E-mail: shanee.pacley@us.af.mil; Brausch, Jacob; Beck-Millerton, Emory [U.S. Air Force Research Laboratory (AFRL)/Wright Patterson Air Force Base, Wright Patterson, Ohio 45433-7707 (United States); Hu, Jianjun; Jespersen, Michael [University of Dayton Research Institute, 300 College Park, Dayton, Ohio 45469 (United States); Hilton, Al [Wyle Laboratories, 4200 Colonel Glenn Hwy, Beavercreek, Ohio 45431 (United States); Waite, Adam [University Technology Corporation, 1270 N Fairfield Rd., Beavercreek, Ohio 45432 (United States); Voevodin, Andrey A. [Department of Materials Science and Engineering, University of North Texas, 1155 Union Circle, Denton, Texas 76203 (United States)

    2016-07-15

    Monolayer molybdenum disulfide (MoS{sub 2}), a two dimensional semiconducting dichalcogenide material with a bandgap of 1.8–1.9 eV, has demonstrated promise for future use in field effect transistors and optoelectronics. Various approaches have been used for MoS{sub 2} processing, the most common being chemical vapor deposition. During chemical vapor deposition, precursors such as Mo, MoO{sub 3}, and MoCl{sub 5} have been used to form a vapor reaction with sulfur, resulting in thin films of MoS{sub 2}. Currently, MoO{sub 3} ribbons and powder, and MoCl{sub 5} powder have been used. However, the use of ribbons and powder makes it difficult to grow large area-continuous films. Sputtering of Mo is an approach that has demonstrated continuous MoS{sub 2} film growth. In this paper, the authors compare the structural properties of MoS{sub 2} grown by sulfurization of pulse vapor deposited MoO{sub 3} and Mo precursor films. In addition, they have studied the effects that reduced graphene oxide (rGO) has on MoS{sub 2} structure. Reports show that rGO increases MoS{sub 2} grain growth during powder vaporization. Herein, the authors report a grain size increase for MoS{sub 2} when rGO was used during sulfurization of both sputtered Mo and MoO{sub 3} precursors. In addition, our transmission electron microscopy results show a more uniform and continuous film growth for the MoS{sub 2} films produced from Mo when compared to the films produced from MoO{sub 3}. Atomic force microscopy images further confirm this uniform and continuous film growth when Mo precursor was used. Finally, x-ray photoelectron spectroscopy results show that the MoS{sub 2} films produced using both precursors were stoichiometric and had about 7–8 layers in thickness, and that there was a slight improvement in stoichiometry when rGO was used.

  1. Mechanical properties of injection molded Fe-6% Ni-0.4% C steels with varying Mo contents of 0.5 to 2%

    Science.gov (United States)

    Matsuda, Mitsuhiro; Miura, Hideshi

    2003-12-01

    In our previous studies, sintered and heat-treated alloy steels (Fe-6Ni-0.5Mo-0.4C (mass%)) produced by a MIM process showed excellent mechanical properties of 2000 MPa tensile strength and 5% elongation. This was attributed to the solid solution strengthening and the mezzo-heterogenous microstruture, which consisted of martensite or retained austenite (Ni and Mo rich phases) surrounded by a network of tempered martensite. This study has been performed to clarify the effect of Mo on the mezzo-heterogeneous microstructure and the mechanical properties of MIM processed and sintered alloy steels (Fe-6Ni-0.4C) with varying Mo content (0.5-2 mass%). The tensile properties of the heat-treated steels with added 2 mass% Mo were lower than those of the steels with added 0.5 mass% Mo. The reduction in the tensile properties, particularly the appearance of large pores formed at the original location of Mo power through the transient liquid phase formation and the low hardness of the matrix, was due to the low sintered density. By using mechanically milled fine Ni and Mo powders, the heat-treated steel (Fe-6Ni-2Mo-0.4C) showed excellent properties, including tensile strength of 1800 MPa and ductility of 2.2% elongation.

  2. Attapulgite-CeO{sub 2}/MoS{sub 2} ternary nanocomposite for photocatalytic oxidative desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiazhang, E-mail: lixiazhang509@163.com [Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164 (China); Jiangsu Key Laboratory for Environment Functional Materials, Suzhou University of Science and Technology, Suzhou 215009 (China); W.M.Keck Center for Advanced Microscopy and Microanalysis, University of Delaware, Newark, DE 19716 (United States); Zhang, Zuosong [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Yao, Chao [Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164 (China); Lu, Xiaowang [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Zhao, Xiaobing [School of Materials Science and Engineering, Changzhou University, Changzhou 213164 (China); Jiangsu Key Laboratory for Environment Functional Materials, Suzhou University of Science and Technology, Suzhou 215009 (China); Ni, Chaoying [W.M.Keck Center for Advanced Microscopy and Microanalysis, University of Delaware, Newark, DE 19716 (United States)

    2016-02-28

    Graphical abstract: - Highlights: • Novel attapulgite(ATP)-CeO{sub 2}/MoS{sub 2} ternary nanocomposites were fabricated. • ATP possessed outstanding adsorption property and enhanced the stability of the network structure. • CeO{sub 2}/MoS{sub 2} couples facilitated the separation of photo-induced electrons and holes. • Mass ratio of CeO{sub 2}/MoS{sub 2} influenced the photocatalytic oxidation desulfurization. - Abstract: Novel attapulgite(ATP)-CeO{sub 2}/MoS{sub 2} ternary nanocomposites were synthesized by microwave assisted assembly method. The structures of the nanocomposites were characterized by XRD, FT-IR, UV–vis, XPS and in situ TEM. The photocatalytic activities of ATP-CeO{sub 2}/MoS{sub 2} composites were investigated by degradating dibenzothiophene (DBT) in gasoline under visible light irradiation. The effect of the mass ratio of CeO{sub 2} to MoS{sub 2} on photocatalytic activity was investigated. The results indicate that the three-dimensional network structure is firmly constructed by ATP skeleton, CeO{sub 2} particles and MoS{sub 2} nanosheet which effectively increase the surface area of the composites and promote the separation of electrons and holes by resulting electronic transmission channels of multi-channel in space. The degradation rate of DBT can reach 95% under 3 h irradiation when the mass ratio of CeO{sub 2}/MoS{sub 2} is 4/10. A plausible mechanism for the photocatalytic oxidative desulfurization of this nanocomposite is put forward.

  3. DFT study of the reactions of Mo and Mo with CO 2 in gas phase

    Indian Academy of Sciences (India)

    Density functional theory (DFT) calculations have been performed to explore the potential energy surfaces of C-O bond activation in CO2 molecule by gas-phase Mo+ cation and Mo atom, in order to better understanding the mechanism of second-row metal reacting with CO2. The minimum energy reaction path is found to ...

  4. Study of tribological behavior of Cu?MoS2 and Ag?MoS2 nanocomposite lubricants

    OpenAIRE

    An, V.; Anisimov, E.; Druzyanova, V.; Burtsev, N.; Shulepov, I.; Khaskelberg, M.

    2016-01-01

    Tribological behavior of Cu?MoS2 and Ag?MoS2 nanocomposite lubricant was studied. Cu nanoparticles produced by electrical explosion of copper wires and Ag nanoparticles prepared by electrospark erosion were employed as metal cladding modifiers of MoS2 nanolamellar particles. The tribological tests showed Cu?MoS2 and Ag?MoS2 nanocomposite lubricants changed the friction coefficient of the initial grease and essentially improved its wear resistance.

  5. Determination of crystallization as a function of Mo layer thickness in Mo/Si multilayers

    DEFF Research Database (Denmark)

    Abdali, Salim; Gerward, Leif; Yakshin, A.E.

    2002-01-01

    information on the crystalline phases, average size and crystallite formation. Comparison of these parameters for the samples examined provided novel results, especially regarding the in-plane and in-depth average sizes of the crystallites. The most important result is that crystallization takes place already......Mo/Si multilayer samples with different Mo layer thickness were deposited by electron beam evaporation, while Kr+ ions (300 eV) were used for polishing the Si layers. Crystallization as a function of the Mo layer thickness deposited was investigated by grazing incidence X-ray diffraction, giving...... when a 1 nm thick Mo layer has been deposited. Moreover, the average in-plane size of the crystallites was found to be independent of the layer thickness, while the average in-depth size corresponded to the thickness of the Mo layer. Depositions consist of polished Si layers were found to give a larger...

  6. Recent results from MoNA-LISA

    Science.gov (United States)

    Spyrou, Artemisia

    2012-03-01

    Studies of the nuclear properties of nuclei close and even beyond the limits of stability have revealed exotic modes of decay and new structural characteristics. The MoNA-LISA array is used at the National Superconducting Cyclotron Laboratory at Michigan State University to study nuclei along the neutron dripline. In a typical experiment, a radioactive beam is employed to produce the neutron-unbound state of interest. This state/resonance immediately decay into a neutron, which is detected by MoNA-LISA and a remaining charged nucleus detected by the sweeper magnet detector suite. In this talk, new exciting findings from recent MoNA-LISA experiments will be presented. These include the first observation of a dineutron decay from ^16Be, the exploration of the ``south shore'' of the Island of Inversion and the first evidence of the decay of the troubling nucleus ^26O.

  7. Vedinių su priesaga *-mo- raida

    Directory of Open Access Journals (Sweden)

    Saulius Ambrazas

    2011-12-01

    Full Text Available DEVELOPMENT OF DERIVATIVES WITH THE SUFFIX *-mo-SummaryAdjectives with the suffix *-mo- have been formed from substantives (cf. Lith. tólimas / tólymas and Latv. dial. tuôl’eims ‘distant’; Pruss. *auktimas ‘high’; Skr. agrimá- ‘the first, who is at the head’ and verbs (cf. Lith. dial. ãpsukmas ‘sewn round’, pliùkšmas ‘deflated, limp’; OLith. laimas ‘happy’ and Pruss. etnīstislaims (gnadenreich III 631; Lith. liñksmas and Latv. lìksms ‘merry, gay, joyfull’, Gmc. *werma- ‘warm’, Skr. bhīmá- ‘terrible, frightfull’, Toch. A, B cämpamo- ‘well-to-do, rich’, Hitt. kišamma- ‘combed’ from the Late Proto-Indo-European. The gratest part of them became participles in the Baltic, Slavic and Albanian languages.On the other hand, the use of derivatives with the suffix *-mo- in the position of abstract nouns is also very old, cf. semanticaly concretized and derivationaly indissoluble abstract noun, in herited from Proto-Indo-European, Lith. dmas (dmai, Latv. dũmi, Pruss. dumis (rauch E 39, Slav. *dymъ, Latv. fūmus, Skr. dhūmó- ‘smoke’ and Gk. θῡ‑μός with abstract meaning ‘soal, vitality, passion,    need’ : dhe-/dh-/dhū- ‘blow; breathe; choke; smoke; rush; disperse; whirl, move, stir’.In the East Baltic languages abstract nouns with the derived suffixes, based on *-mo-, became productive, cf. nomina actionis with *-i-mo- in Lithuanian (cf. gyvẽnimas ‘life’ and corresponding derivatives with *-u-mo- in Latvian (cf. ìeradums ‘custom, habit’.

  8. mo encontrar patentes, setiembre 2010

    OpenAIRE

    Bonich, Mònica; Cervera-Farré, Albert; Santos-Hermosa, Gema

    2010-01-01

    Com es poden trobar les patents: què són les patents?, què es pot patentar?, qui assigna les patents? i com es poden trobar patents? Cómo encontrar patentes: ¿qué son las patentes?, ¿qué se puede patentar?, ¿quién asigna las patentes? y ¿cómo se pueden encontrar patentes? How to find patents: what are patents?, what can be patented?, who awards the patents? and how can patents be found?

  9. Spektroskopie a spektroelektrochemie MoS2

    OpenAIRE

    Jurková, Kateřina

    2014-01-01

    This work deals with studies MoS2 layers prepared by mechanical exfoliation was detected by optical microscopy and the number of layers was determined from AFM measurement. The layers were characterized by Raman spectroscopy in various wavelengths. A spectroelectrochemical cell for the sandwich sample consisting of a MoS2 layer and two layers of graphene with various isotope composition and Raman spectra measurements were performed at voltages from 0.0 V to 0.9 V. A larger shift of the G band...

  10. Elevated Temperature Tensile Tests on DU–10Mo Rolled Foils

    Energy Technology Data Exchange (ETDEWEB)

    Schulthess, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Tensile mechanical properties for uranium-10 wt.% molybdenum (U–10Mo) foils are required to support modeling and qualification of new monolithic fuel plate designs. It is expected that depleted uranium-10 wt% Mo (DU–10Mo) mechanical behavior is representative of the low enriched U–10Mo to be used in the actual fuel plates, therefore DU-10Mo was studied to simplify material processing, handling, and testing requirements. In this report, tensile testing of DU-10Mo fuel foils prepared using four different thermomechanical processing treatments were conducted to assess the impact of foil fabrication history on resultant tensile properties.

  11. Defect Healing and Charge Transfer-Mediated Valley Polarization in MoS2/MoSe2/MoS2Trilayer van der Waals Heterostructures.

    Science.gov (United States)

    Surrente, Alessandro; Dumcenco, Dumitru; Yang, Zhuo; Kuc, Agnieszka; Jing, Yu; Heine, Thomas; Kung, Yen-Cheng; Maude, Duncan K; Kis, Andras; Plochocka, Paulina

    2017-07-12

    Monolayer transition metal dichalcogenides (TMDCs) grown by chemical vapor deposition (CVD) are plagued by a significantly lower optical quality compared to exfoliated TMDCs. In this work, we show that the optical quality of CVD-grown MoSe 2 is completely recovered if the material is sandwiched in MoS 2 /MoSe 2 /MoS 2 trilayer van der Waals heterostructures. We show by means of density functional theory that this remarkable and unexpected result is due to defect healing: S atoms of the more reactive MoS 2 layers are donated to heal Se vacancy defects in the middle MoSe 2 layer. In addition, the trilayer structure exhibits a considerable charge-transfer mediated valley polarization of MoSe 2 without the need for resonant excitation. Our fabrication approach, relying solely on simple flake transfer technique, paves the way for the scalable production of large-area TMDC materials with excellent optical quality.

  12. Isothermal and Two-Temperature Zone Selenization of Mo Layers

    Directory of Open Access Journals (Sweden)

    L. Kaupmees

    2012-01-01

    Full Text Available Glass/Mo, Mo foil, glass/Mo/In, and glass/Mo/Cu stacked layers were selenized in closed vacuum tubes by isothermal and/or two-temperature zone annealing in Se vapors. The selenization process was studied dependent on Se vapor pressure, temperature and time. Samples were selenized from 375 to 580°C for 30 and 60 minutes. The applied Se pressure was varied between 130 and 4.4⋅103 Pa. The increase of MoSe2 film thickness was found to depend on the origin of Mo. MoSe2 thickness dL on Mo-foil was much higher than on sputtered Mo layers, and it depended linearly on time and as a power function dL~PSe1/2 on Se vapor pressure. The residual oxygen content in the formed MoSe2 layers was much lower in the two-zone selenization process. If Mo was covered with Cu or In before selenization, these were found to diffuse into formed MoSe2 layer. All the MoSe2 layers showed p-type conductivity.

  13. MoS2 PARTICLES MODIFIED WITH POLYSTYRENE FOR PRODUCING Ni–PS/MoS2 COATINGS

    OpenAIRE

    ZHONGJIA HUANG; DANGSHENG XIONG

    2008-01-01

    The MoS2 particles were coated with polystyrene and can be written as PS/MoS2 hereinafter. Ni–PS/MoS2 coatings and Ni–MoS2 coatings were produced by PC electrodeposition technique. The surface morphology of Ni–PS/MoS2 coating was examined and compared with those of Ni–MoS2 coating. The effect of particle concentrations on the volume percent of particles incorporated in the coatings was investigated. And the microhardness of coatings was also investigated. Results show that the surface morphol...

  14. Blistering behavior in Mo/Si multilayers

    NARCIS (Netherlands)

    Kuznetsov, Alexey; Gleeson, Michael; van de Kruijs, Robbert Wilhelmus Elisabeth; Bijkerk, Frederik; Kuznetsov, A.S.

    2011-01-01

    This paper is concerned with mapping the characteristics of blistering induced on Mo/Si multilayers as a result of irradiation by hydrogen species generated in a thermal capillary cracker. The nature and extent of the damage observed is dependent on exposure conditions such as the sample

  15. Teens join the MoEDAL collaboration

    CERN Multimedia

    Stephanie Hills

    2013-01-01

    The principal investigator for any institute joining an experimental collaboration is generally a self-assured researcher with evident leadership skills and an in-depth knowledge of their subject gained over many years. Katherine Evans fits the brief in every respect, except that she is 17 years old and her research institute is the Langton Star Centre, based at the Simon Langton Grammar School for Boys. The school has just joined the MoEDAL experiment.   Teacher Becky Parker (left) with two students from the Simon Langton Grammar School for Boys in the MoEDAL experimental area. MoEDAL, the latest LHC experiment has detectors located close to the interaction point of the LHCb experiment. This new experiment is designed to search for the highly ionizing avatars of new physics at the LHC, specifically the magnetic monopole or dyon and other highly ionizing stable massive particles from a number of beyond-the-Standard-Model scenarios. MoEDAL was approved in 2010 and is due to start taking data i...

  16. MoEDAL AND MAGNETIC MONOPOLES

    CERN Multimedia

    Paola Catapano

    2016-01-01

    The LHC MoEDAL experiment publishes its first paper on its search for magnetic monopoles Geneva XXXX. In a paper published by the journal JHEP today, the MoEDAL experiment at CERN narrows the window of where to search for a hypothetical particle, the magnetic monopole. Over the last decades, experiments have been trying to find evidence for magnetic monopoles at accelerators, including at CERN’s Large Hadron Collider. Such particles were first predicted by physicist Paul Dirac in the 1930s but have never been observed so far. “Today MoEDAL celebrates the release of its first physics result and joins the other LHC experiments at the discovery frontier," says Spokesperson of the MoEDAL experiment, James Pinfold. Just as electricity comes with two charges, positive and negative, so magnetism comes with two poles, North and South. The difference is that while it’s easy to isolate a positive or negative electric charge, nobody has ever seen a solitary magnetic charge, or monopole. If you

  17. Measurement of the direct CP -violating parameter ACP in the decay D<mo>+ stretchy='false'>→mo>K<mo>-mo>π<mo>+mo>π+>

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Borysova, M.; Brandt, A.; Brandt, O.; Brock, R.; Bross, A.; Brown, D.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M. -C.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, V. N.; Fauré, A.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Gogota, O.; Golovanov, G.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J. -F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jeong, M. S.; Jesik, R.; Jiang, P.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kajfasz, E.; Karmanov, D.; Katsanos, I.; Kaur, M.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Lammers, S.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nguyen, H. T.; Nunnemann, T.; Orduna, J.; Osman, N.; Osta, J.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M. -A.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Ratoff, P. N.; Razumov, I.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santos, A. S.; Savage, G.; Savitskyi, M.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Simak, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stoyanova, D. A.; Strauss, M.; Suter, L.; Svoisky, P.; Titov, M.; Tokmenin, V. V.; Tsai, Y. -T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verkheev, A. Y.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Williams, M. R. J.; Wilson, G. W.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yang, S.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yin, H.; Yip, K.; Youn, S. W.; Yu, J. M.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.

    2014-12-01

    We measure the direct CP-violating parameter ACP for the decay of the charged charm meson, Dmo>+ stretchy="false">→mo>Kmo>-mo>πmo>+mo>πmo>+> (and charge conjugate), using the full 10.4 fbmo>->1 sample of ppmo accent="true" stretchy="false">¯mo> collisions at smo>=>1.96 TeV collected by the D0 detector at the Fermilab Tevatron collider. We extract the raw reconstructed charge asymmetry by fitting the invariant mass distributions for the sum and difference of charge-specific samples. This quantity is then corrected for detector-related asymmetries using data-driven methods and for possible physics asymmetries (from Bmo stretchy="false">→mo

  18. One-step synthesis of NiTe2 nanorods coated with few-layers MoS2 for enhancing photocatalytic activity.

    Science.gov (United States)

    Lei, Yu-Xi; Zhou, Jian-Ping; Ul Hassan, Qadeer; Wang, Jing-Zhou

    2017-12-08

    A facile one-step hydrothermal process was developed for fabrication of three-dimensional hierarchical NiTe2@MoS2 heterostructures. A few layers of MoS2 uniformly grew on the NiTe2 nanorods, possessing a higher surface area. The strategy was extended to CoTe2@MoS2 heterostructures with a few layers of MoS2. The photocatalytic activities of the heterostructures were evaluated by the photodegradation of methylene blue. The composites show strong adsorption ability and much better photocatalytic efficiency in comparison with pure MoS2 microflowers and NiTe2 nanorods. Especially, the NiTe2@MoS2 heterostructure with 40 wt% of MoS2 presents the highest performance in photocatalytic degradation of dye molecules, which is attributed to the formation of hierarchical network between NiTe2 nanorods and MoS2 nanosheets. And the possible mechanism of the enhanced photocatalytic activities was discussed.

  19. One-step synthesis of NiTe2 nanorods coated with few-layers MoS2 for enhancing photocatalytic activity

    Science.gov (United States)

    Lei, Yu-Xi; Zhou, Jian-Ping; Hassan, Qadeer Ul; Wang, Jing-Zhou

    2017-12-01

    A facile one-step hydrothermal process was developed for fabrication of three-dimensional hierarchical NiTe2@MoS2 heterostructures. A few layers of MoS2 uniformly grew on the NiTe2 nanorods, possessing a higher surface area. The strategy was extended to CoTe2@MoS2 heterostructures with a few layers of MoS2. The photocatalytic activities of the heterostructures were evaluated by the photodegradation of methylene blue. The composites show strong adsorption ability and much better photocatalytic efficiency in comparison with pure MoS2 microflowers and NiTe2 nanorods. Especially, the NiTe2@MoS2 heterostructure with 40 wt% of MoS2 presents the highest performance in photocatalytic degradation of dye molecules, which is attributed to the formation of hierarchical network between NiTe2 nanorods and MoS2 nanosheets. And the possible mechanism of the enhanced photocatalytic activities was discussed.

  20. Analysis of MoDOT communication and outreach effectiveness

    Science.gov (United States)

    2008-07-01

    Personal interviews were held with MoDOT personnel to assess MoDOTs current communication practices and existing customer segmentation practices. Focus groups were then held to help gauge the effectiveness of existing communication practices and t...

  1. Structure, morphology and corrosion resistance of Ni–Mo+PTh ...

    Indian Academy of Sciences (India)

    PTh, (2) Mo+4.9%PTh and (3) Ni−21.7%Mo. potential Ni–Mo coatings containing comparable content of. Mo is equal −0.780 V (figure 3). Increase of polythiophene contents in coatings, causes decrease of corrosion current. (table 1). Result of this change of corrosion current is increase of polarization resistance from 18.8 to ...

  2. Vertical MoSe2-MoOxp-n heterojunction and its application in optoelectronics.

    Science.gov (United States)

    Chen, Xiaoshuang; Liu, Guangbo; Hu, Yunxia; Cao, Wenwu; Hu, PingAn; Hu, Wenping

    2018-01-26

    The hybrid n-type 2D transition-metal dichalcogenide (TMD)/p-type oxide van der Waals (vdW) heterojunction nanosheets consist of 2D layered MoSe 2 (the n-type 2D material) and MoO x (the p-type oxide) which are grown on SiO 2 /Si substrates for the first time via chemical vapor deposition technique, displaying the regular hexagon structures with the average length dimension of sides of ∼8 μm. Vertical MoSe 2 -MoO x p-n heterojunctions demonstrate obviously current-rectifying characteristic, and it can be tuned via gate voltage. What is more, the photodetector based on vertical MoSe 2 -MoO x heterojunctions displays optimal photoresponse behavior, generating the responsivity, detectivity, and external quantum efficiency to 3.4 A W -1 , 0.85 × 10 8 Jones, and 1665.6%, respectively, at V ds  = 5 V with the light wavelength of 254 nm under 0.29 mW cm -2 . These results furnish a building block on investigating the flexible and transparent properties of vdW and further optimizing the structure of the devices for better optoelectronic and electronic performance.

  3. Graphene Versus MoS2: a Short Review

    OpenAIRE

    Jiang, Jin-Wu

    2014-01-01

    Graphene and MoS2 are two well-known quasi two-dimensional materials. This review is a comparative survey of the complementary lattice dynamical and mechanical properties of graphene and MoS2. This comparison facilitates the study of graphene/MoS2 heterostructures, which is expected to mitigate the negative properties of each individual constituent.

  4. Electron microscopy studies on MoS2 nanocrystals

    DEFF Research Database (Denmark)

    Hansen, Lars Pilsgaard

    Industrial-style MoS2-based hydrotreating catalysts are studied using electron microscopy. The MoS2 nanostructures are imaged with single-atom sensitivity to reveal the catalytically important edge structures. Furthermore, the in-situ formation of MoS2 crystals is imaged for the first time....

  5. Auger Spectroscopy Analysis of Spalled LEU-10Mo Foils

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, Samantha Kay [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Schulze, Roland K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-03

    Presentation includes slides on Surface Science used to probe LEU-10Mo Spall; Auger highlights graphitic-like inclusions and Mo-deficient oxide on base metal; Higher C concentration detected within spall area Images Courtesy; Depth profiling reveals thick oxide; Mo concentration nears nominal only at depths ~400 nm; and lastly Key Findings.

  6. 76 FR 31822 - Amendment of Class E Airspace; Mosby, MO

    Science.gov (United States)

    2011-06-02

    ... Federal Aviation Administration 14 CFR Part 71 Amendment of Class E Airspace; Mosby, MO AGENCY: Federal... Mosby, MO. Decommissioning of the Mosby non-directional beacon (NDB) at Midwest National Air Center Airport, Mosby, MO, has made this action necessary to enhance the safety and management of Instrument...

  7. 76 FR 43576 - Amendment of Class E Airspace; Hannibal, MO

    Science.gov (United States)

    2011-07-21

    ... Federal Aviation Administration 14 CFR Part 71 Amendment of Class E Airspace; Hannibal, MO AGENCY: Federal... Hannibal, MO. Decommissioning of the Hannibal non-directional beacon (NDB) at Hannibal Regional Airport, Hannibal, MO, has made this action necessary to enhance the safety and management of Instrument Flight Rule...

  8. Network analysis identifies ELF3 as a QTL for the shade avoidance response in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    José M Jiménez-Gómez

    2010-09-01

    Full Text Available Quantitative Trait Loci (QTL analyses in immortal populations are a powerful method for exploring the genetic mechanisms that control interactions of organisms with their environment. However, QTL analyses frequently do not culminate in the identification of a causal gene due to the large chromosomal regions often underlying QTLs. A reasonable approach to inform the process of causal gene identification is to incorporate additional genome-wide information, which is becoming increasingly accessible. In this work, we perform QTL analysis of the shade avoidance response in the Bayreuth-0 (Bay-0, CS954 x Shahdara (Sha, CS929 recombinant inbred line population of Arabidopsis. We take advantage of the complex pleiotropic nature of this trait to perform network analysis using co-expression, eQTL and functional classification from publicly available datasets to help us find good candidate genes for our strongest QTL, SAR2. This novel network analysis detected EARLY FLOWERING 3 (ELF3; AT2G25930 as the most likely candidate gene affecting the shade avoidance response in our population. Further genetic and transgenic experiments confirmed ELF3 as the causative gene for SAR2. The Bay-0 and Sha alleles of ELF3 differentially regulate developmental time and circadian clock period length in Arabidopsis, and the extent of this regulation is dependent on the light environment. This is the first time that ELF3 has been implicated in the shade avoidance response and that different natural alleles of this gene are shown to have phenotypic effects. In summary, we show that development of networks to inform candidate gene identification for QTLs is a promising technique that can significantly accelerate the process of QTL cloning.

  9. A systematic first principle method to study magnetic properties of FeMo, CoMo and NiMo

    CERN Document Server

    Bhattacharjee, A K; Halder, A; Mookerjee, A; Touheed, M

    2003-01-01

    We use the first principle TB-LMTO (Tight-Binding Linear Muffin Tin Orbital) method combined with the ASM (Augmented Space Method) to take care of disorder beyond the mean field (CPA - Cohetent Potential Approximation) approximation. We analyze binary alloys between magnetic transition metals Fe, Co, Ni and non-magnetic Mo to find out the effect of disorder on electronic structure and consequently magnetic properties of the alloys.

  10. High pressure effect on MoS2 and MoSe2 single crystals grown by ...

    Indian Academy of Sciences (India)

    Unknown

    tetrahedral anvil apparatus up to 5 GPa. In this paper we report room temperature resistance mea- surements as a function of pressure on MoS2 and MoSe2 single crystals. In each case the resistance decreases un- der pressure due to an increase in the carrier concentration. 2. Experimental. Single crystals of MoS2 and ...

  11. Electromagnetic structure of {sup 98}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Zielinska, M. E-mail: magda@slcj.uw.edu.pl; Czosnyka, T.; Choinski, J.; Iwanicki, J.; Napiorkowski, P.; Srebrny, J.; Toh, Y.; Oshima, M.; Osa, A.; Utsuno, Y.; Hatsukawa, Y.; Katakura, J.; Koizumi, M.; Matsuda, M.; Shizuma, T.; Sugawara, M.; Morikawa, T.; Kusakari, H.; Efimov, A.D.; Mikhajlov, V.M

    2002-12-16

    The nucleus {sup 98}Mo was multiply Coulomb excited using {sup 20}Ne, {sup 84}Kr and {sup 136}Xe beams. Eighteen E2 and M1 reduced matrix elements connecting 7 low-lying levels have been determined using the least-squares code GOSIA. The results are compared with the predictions of an extended version of the IBM1 model. The quadrupole sum rules approach was used to determine the shape parameters in two 0{sup +} (ground and first excited) states. The rotational invariants and obtained show the shape coexistence in {sup 98}Mo nucleus: the triaxial ground state and the prolate first excited state.

  12. Moïse égyptien

    OpenAIRE

    Le Rider, Jacques

    2011-01-01

    En affirmant que Moïse était un Égyptien, Freud coupe à la racine les tentations de rechute dans les représentations « biologiques », « héréditaires » et « ethniques » de l’identité juive. Celle-ci devient une affaire de mémoire familiale, d’identification, de décision personnelle, de méthode scientifique et d’éthique. L’homme Moïse et la religion monothéiste est un exemple de l’assimilation de certains intellectuels allemands et viennois, non à la culture chrétienne, mais à la modernité scie...

  13. Level studies of 93Mo via 93Nb(p, nγ93Mo reaction and density of discrete levels in 93Mo

    Directory of Open Access Journals (Sweden)

    Razavi Rohallah

    2011-01-01

    Full Text Available The excited states of 93Mo have been investigated via the 93Nb(P,nγ93Mo reaction with proton beam energies of 2.5-4.3 MeV. The parameters of the nuclear level density formula were determined from the extensive and complete level scheme of 93Mo. The Bethe formula for the back-shifted Fermi gas model and the constant temperature model are compared with experimental level densities.

  14. Structures and magnetic properties of double perovskites A sub 2 LnMO sub 6 and 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 (A=Sr, Ba; Ln=Y, lanthanides; M=Nb, Ta, Ru)

    CERN Document Server

    Hinatsu, Y

    2003-01-01

    This account describes the synthesis, crystal structures and magnetic properties of double perovskites A sub 2 LnMO sub 6 and 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 (A=Sr, Ba; Ln=Y, lanthanides; M=Nb, Ta, Ru). The double perovskites A sub 2 LnMO sub 6 have two kinds of cations, Ln and M, in the B site of the perovskite ABO sub 3. These cations adopt the alternative ordered arrangement. Measurements of the magnetic susceptibility, specific heat, and powder neutron diffraction showed that all of the A sub 2 LnRuO sub 6 compounds exhibited an antiferromagnetic transition at low temperatures and a complex temperature dependence of the magnetic susceptibility below their transition temperatures. In these compounds, the magnetic interaction between the Ln (4f electrons) and Ru (4d electrons) ions via the Ln-O-Ru pathway contributes greatly to their magnetic cooperative phenomena. The structural and magnetic studies for the 6H-perovskites Ba sub 3 LnRu sub 2 O sub 9 show that the Ln cations occupy the corner-sha...

  15. Improvement of low temperature oxidation resistance in MoSi{sub 2}-oxides composites; Sankabutsu no fukugoka ni yoru MoSi{sub 2} zairyo no teion sanka tokusei no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, W.; Uchiyama, T. [Riken Corp., Saitama (Japan)

    1999-11-15

    MoSi{sub 2}-oxides composites using fine aluminosilicate powder (< 0.2{mu}m) have demonstrated excellent low temperature oxidation resistance and thermal shock resistance. These properties strongly depend on microstructural morphology and are obtained in composites that network-structures of both phases of MoSi{sub 2} and oxides are developed, i.e., in composites with oxides of 20 {approx} 40 vol. %. When one phase is independently dispersed in the other phase, on the other hand, problems of low temperature oxidation and thermal shock occur. The low temperature oxidation problem occurs in the composites with oxides less than 15 vol. % and the thermal shock problem occurs in the composites with oxides more than 50 vol. %. These results will contribute to material design approaches for high temperature structural applications of MoSi{sub 2}. (author)

  16. Multi-functional integration of pore P25@C@MoS{sub 2} core-double shell nanostructures as robust ternary anodes with enhanced lithium storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Biao [School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350 (China); Zhao, Naiqin [School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350 (China); Collaborative Innovation Centre of Chemical Science and Engineering, Tianjin 300072 (China); Wei, Chaopeng; Zhou, Jingwen; He, Fang; Shi, Chunsheng; He, Chunnian [School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350 (China); Liu, Enzuo, E-mail: ezliu@tju.edu.cn [School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300350 (China); Collaborative Innovation Centre of Chemical Science and Engineering, Tianjin 300072 (China)

    2017-04-15

    Highlights: • P25@carbon supported MoS{sub 2} composite was prepared by a one-step process. • The distribution and interaction of C, MoS{sub 2} and TiO{sub 2} are systematically examined. • The enjoyable features of the three components are complementarily integrated. • The smart ternary electrode exhibits excellent cycling stability and rate capability. - Abstract: Ternary anodes have attracted more and more attention due to the characteristic advantages resulting from the effect integration of three different materials on the lithium storage mechanism with functional interfaces interaction. However, clarifying the distribution and interaction of carbon, MoS{sub 2} and TiO{sub 2} in the MoS{sub 2}/C/TiO{sub 2} composite, which is helpful for the understanding of the formation and lithium storage mechanism of the ternary anodes, is a well-known challenge. Herein, a novel pore core-double shell nanostructure of P25@carbon network supported few-layer MoS{sub 2} nanosheet (P25@C@FL-MoS{sub 2}) is successfully synthesized by a one-pot hydrothermal approach. The distribution and interaction of the carbon, MoS{sub 2} and TiO{sub 2} in the obtained P25@C@FL-MoS{sub 2} hybrid are systematically characterized by transmission electron microscopy, Raman spectra and X-ray photoelectron spectroscopy analysis et al. It is found that the carbon serves as binder, which supports few-layer MoS{sub 2} shell and coats the P25 core via Ti−O−C bonds at the same time. Such multi-functional integration with smart structure and strong interfacial contact generates favorable structure stability and interfacial pseudocapacity-like storage mechanism. As a consequence, superior cycling and rate capacity of the muti-functional integration ternary P25@C@FL-MoS{sub 2} anode are achieved.

  17. Learning Networks, Networked Learning

    NARCIS (Netherlands)

    Sloep, Peter; Berlanga, Adriana

    2010-01-01

    Sloep, P. B., & Berlanga, A. J. (2011). Learning Networks, Networked Learning [Redes de Aprendizaje, Aprendizaje en Red]. Comunicar, XIX(37), 55-63. Retrieved from http://dx.doi.org/10.3916/C37-2011-02-05

  18. Synthesis of Fine Mo2C Powder from Prereduced Mo in Undiluted CH4 Flow

    Science.gov (United States)

    Cetinkaya, S.; Eroglu, S.

    2017-10-01

    The carburization behavior of prereduced Mo was investigated in undiluted CH4 flow at 900-1000 K. Prior to the experiments, equilibrium thermodynamic analysis was carried out in the Mo-C-H system. The products were characterized by mass measurement, x-ray diffraction and scanning electron microscopy techniques. A single Mo2C phase was obtained within 45 min, 5 min, and 2.5 min at 900 K, 950 K, and 1000 K, respectively, at CH4 contents higher than the predicted ones. The reasons for this behavior were discussed in terms of CH4 stability, open tube flow, and self-created atmosphere in the powder bed. The fractional conversion-time curves indicated that the carburization kinetics followed a linear rate law. The Mo2C crystallite size (26-37 nm) and platelet thickness (50-100 nm) were found to be smaller than those of the parent Mo phase. These findings were attributable to the defects formed as a result of stresses associated with the reduction and the carburization.

  19. A density-functional study of the structures, binding energies and magnetic moments of the clusters Mo{sub N} (N = 2-13), Mo{sub 12}Fe, Mo{sub 12}Co and Mo{sub 12}Ni

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera-Granja, F [Instituto de Fisica, Universidad Autonoma de San Luis PotosI, SLP 78000 (Mexico); Vega, A [Departamento de Fisica Teorica, Atomica, y Optica, Universidad de Valladolid, E-47011 Valladolid (Spain); Gallego, L J [Departamento de Fisica de la Materia Condensada, Facultad de Fisica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela (Spain)

    2008-04-09

    We report the results of density-functional calculations of the structures, binding energies and magnetic moments of the clusters Mo{sub N} (N = 2-13), Mo{sub 12}Fe, Mo{sub 12}Co and Mo{sub 12}Ni that were performed using the SIESTA method within the generalized gradient approximation for exchange and correlation. For pure Mo{sub N} clusters, we obtain collinear magnetic structures in all cases, even when the self-consistent calculations were started from non-collinear inputs. Our results for these clusters show that both linear, planar and three-dimensional clusters have a strong tendency to form dimers. In general, even-numbered clusters are more stable than their neighbouring odd-numbered clusters because they can accommodate an integer number of tightly bound dimers. As a consequence, the binding energies of pure Mo{sub N} clusters, in their lowest-energy states, exhibit an odd-even effect in all dimensionalities. Odd-even effects are less noticeable in the magnetic moments than in the binding energies. When comparing our results for pure Mo clusters with those obtained recently by other authors, we observe similarities in some cases, but striking differences in others. In particular, the odd-even effect in three-dimensional Mo clusters was not observed before, and our results for some clusters (e.g. for planar Mo{sub 3} and Mo{sub 7} and for three-dimensional Mo{sub 7} and Mo{sub 13}) differ from those reported by other authors. For Mo{sub 12}Fe and Mo{sub 12}Ni, we obtain that the icosahedral configuration with the impurity atom at the cluster surface is more stable than the configuration with the impurity at the central site, while the opposite occurs in the case of Mo{sub 12}Co. In Mo{sub 12}Co and Mo{sub 12}Ni, the impurities exhibit a weak magnetic moment parallely coupled to the total magnetic moment of the Mo atoms, whereas in Mo{sub 12}Fe the impurity shows a high moment with antiparallel coupling.

  20. Scheelite-type sodium neodymium(III ortho-oxidomolybdate(VI, NaNd[MoO4]2

    Directory of Open Access Journals (Sweden)

    Thomas Schleid

    2011-12-01

    Full Text Available Scheelite-type NaNd[MoO4]2 contains one crystallographic position (site symmetry overline4 for the large cations, which is mixed-occupied by Na+ and Nd3+ cations in a 1:1 molar ratio. Thus, both are surrounded by eight O atoms in the shape of a trigonal dodecahedron. Furthermore, the structure consists of crystallographically unique [MoO4]2− units (site symmetry overline4 surrounded by eight sodium and neodymium cations, which are all vertex-attached. The polyhedra around the Na+/Nd3+ cations are connected to four others via common edges, building up a three-dimensional network in whose tetrahedral voids of O atoms the Mo6+ cations reside.

  1. Thinking in networks: artistic–architectural responses to ubiquitous information

    Directory of Open Access Journals (Sweden)

    Yvonne Spielmann

    2011-12-01

    Full Text Available The article discusses creative practices that in aesthetical-technical ways intervene into the computer networked communication systems.I am interested in artist practices that use networks in different ways to make us aware about the possibilities to rethink media-cultural environments. I use the example of the Japanese art-architectural group Double Negative Architecture to give an example of creatively thinking in networks.Yvonne Spielmann (Ph.D., Dr. habil. is presently Research Professor and Chair of New Media at The University of the West of Scotland. Her work focuses on inter-relationships between media and culture, technology, art, science and communication, and in particular on Western/European and non-Western/South-East Asian interaction. Milestones of publish research output are four authored monographs and about 90 single authored articles. Her book, “Video, the Reflexive Medium” (published by MIT Press 2008, Japanese edition by Sangen-sha Press 2011 was rewarded the 2009 Lewis Mumford Award for Outstanding Scholarship in the Ecology of Technics. Her most recent book “Hybrid Cultures” was published in German by Suhrkamp Press in 2010, English edition from MIT Press in 2012. Spielmann's work has been published in German and English and has been translated into French, Polish, Croatian, Swedish, Japanese, and Korean. She holds the 2011 Swedish Prize for Swedish–German scientific co-operation.

  2. SHA-1, SAT-solving, and CNF

    CSIR Research Space (South Africa)

    Motara, YM

    2017-09-01

    Full Text Available . The per-round output in this stage is denoted by the symbol a, and it is therefore the last five 32-bit words, comprising the final 160 bits generated by the compression function, which will have particular values for a given 16-word input. The output may..., and this means that SAT-solvers are worse than brute force solutions as far as the preimage problem is concerned. This result is not surprising. However, the vastly different behaviours of the different SAT-solvers when faced with different encodings...

  3. PODAAC-J1SHA-NETGC

    Data.gov (United States)

    National Aeronautics and Space Administration — These Sea Surface Height Anomalies (SSHA) are derived from the Jason-1 Geophysical Data Record (GDR) Geodetic Mission. Jason-1 is an altimetric mission whose...

  4. Two new hybrid molybdenum arsenate derivative constructed from [As2Mo6O26]6- building: Synthesis, structural characterization and photocatalysis property

    Science.gov (United States)

    Zhang, Xiao; Luo, Xuan; Duan, Yuanling; Huang, Yanping; Zhang, Nanxi; Zhao, Liyan; Wu, Jie

    2017-08-01

    Two new inorganic-organic hybrid materials [Cu(enMe)2]2{(As2Mo6O26) [Cu(enMe)2]}·4H2O (1) and [As2Mo6(OH)2O24][Cu(H2O)2(phen)]2 (2) (enMe = 1,2'-propanediamine, phen = 1,10'-phenanthroline) based on [As2Mo6O26]6- building blocks, denoted as [As2Mo6], have been obtained by hydrothermal methods. 1 shows a 1-D straight chain structure constructed form [As2Mo6] building blocks and [Cu(enMe)2] complexes, and then extended to 3-D supramolecular network by lattice water via hydrogen bonds interactions. 2 exhibits a new 1-D covalent ribbon with large rectangular grids formed from [As2Mo6] building blocks connected by [Cu(H2O)2(phen)] complexes, then extended into 3-D supramolecular network via hydrogen bonds and π···π interactions. In additional, the photocatalytic activity for methylene blue degradation under visible-light irradiation of 2 was investigated.

  5. Ni–Mo and Co–Mo alloy nanoparticles for catalytic chemical vapor deposition synthesis of carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Lobiak, E.V., E-mail: lobiakev@niic.sbras.ru [Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090 Novosibirsk (Russian Federation); Shlyakhova, E.V.; Bulusheva, L.G.; Plyusnin, P.E.; Shubin, Yu.V.; Okotrub, A.V. [Nikolaev Institute of Inorganic Chemistry, SB RAS, 3 Acad. Lavrentiev Ave., 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2 Pirogova Str., Novosibirsk 630090 (Russian Federation)

    2015-02-05

    Highlights: • Thermal decomposition of the ε-Keggin-type polyoxomolybdate clusters Mo{sub 12}O{sub 28}(μ{sub 2}-OH){sub 12}{Ni(H_2O)_3}{sub 4} and Mo{sub 12}O{sub 28}(μ{sub 2}-OH){sub 12}{Co(H_2O)_3}{sub 4} produces NiMoO{sub 4} and CoMoO{sub 4} phases. • The NiMoO{sub 4} and CoMoO{sub 4} phases are converted in alloys with a metal ratio of 1:1. • The Ni–Mo and Co–Mo alloy nanoparticles catalyze a CCVD growth of carbon nanotubes. - Abstract: Here, we show for the first time a catalytic chemical vapor deposition (CCVD) synthesis of carbon nanotubes (CNTs) using polyoxomolybdate clusters Mo{sub 12}O{sub 28}(μ{sub 2}-OH){sub 12}{Ni(H_2O)_3}{sub 4} and Mo{sub 12}O{sub 28}(μ{sub 2}-OH){sub 12}{Co(H_2O)_3}{sub 4} as a source of catalyst nanoparticles. X-ray diffraction analyses indicated that the products of thermal decomposition of the clusters contain NiMoO{sub 4} and CoMoO{sub 4} phases, which are converted into Ni–Mo and Co–Mo alloys at 900 °C in hydrogen environment. High-resolution transmission electron microscopy in combination with energy-dispersive X-ray spectroscopy confirmed the CNT growth from bimetallic nanoparticles. Synergism between two metals in an alloy resulted in large-scale production of non-bundled few-walled CNTs with narrow diameter distribution and high quality.

  6. A network of networks.

    Science.gov (United States)

    Iedema, Rick; Verma, Raj; Wutzke, Sonia; Lyons, Nigel; McCaughan, Brian

    2017-04-10

    Purpose To further our insight into the role of networks in health system reform, the purpose of this paper is to investigate how one agency, the NSW Agency for Clinical Innovation (ACI), and the multiple networks and enabling resources that it encompasses, govern, manage and extend the potential of networks for healthcare practice improvement. Design/methodology/approach This is a case study investigation which took place over ten months through the first author's participation in network activities and discussions with the agency's staff about their main objectives, challenges and achievements, and with selected services around the state of New South Wales to understand the agency's implementation and large system transformation activities. Findings The paper demonstrates that ACI accommodates multiple networks whose oversight structures, self-organisation and systems change approaches combined in dynamic ways, effectively yield a diversity of network governances. Further, ACI bears out a paradox of "centralised decentralisation", co-locating agents of innovation with networks of implementation and evaluation expertise. This arrangement strengthens and legitimates the role of the strategic hybrid - the healthcare professional in pursuit of change and improvement, and enhances their influence and impact on the wider system. Research limitations/implications While focussing the case study on one agency only, this study is unique as it highlights inter-network connections. Contributing to the literature on network governance, this paper identifies ACI as a "network of networks" through which resources, expectations and stakeholder dynamics are dynamically and flexibly mediated and enhanced. Practical implications The co-location of and dynamic interaction among clinical networks may create synergies among networks, nurture "strategic hybrids", and enhance the impact of network activities on health system reform. Social implications Network governance requires more

  7. Phase equilibria of the Mo-Al-Ho ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yitai; Chen, Xiaoxian; Liu, Hao [Guangxi Univ., Nanning (China). College of Materials Science and Engineering; Guangxi Univ., Nanning (China). Guangxi Key Laboratory of Processing for Non-ferrous Metal and Featured Materials; Zhan, Yongzhong [Guangxi Univ., Nanning (China). College of Materials Science and Engineering; Guangxi Univ., Nanning (China). Guangxi Key Laboratory of Processing for Non-ferrous Metal and Featured Materials; Guangxi Univ., Nanning (China). Center of Ecological Collaborative Innovation for Aluminum Industry

    2017-08-15

    Investigation into the reactions and phase equilibria of transition metal elements (i.e. Mo, Zr, Cr, V and Ti), Al and rare earths is academically and industrially important for the development of both refractory alloys and lightweight high-temperature materials. In this work, the equilibria of the Mo-Al-Ho ternary system at 773 K have been determined by using X-ray powder diffraction and scanning electron microscopy equipped with energy dispersive X-ray analysis. A new ternary phase Al{sub 4}Mo{sub 2}Ho has been found and the other ternary phase Al{sub 43}Mo{sub 4}Ho{sub 6} is observed. Ten binary phases in the Al-Mo and Al-Ho systems, including Al{sub 17}Mo{sub 4} rather than Al{sub 4}Mo, have been determined to exist at 773 K. The homogeneity ranges of AlMo{sub 3} and Al{sub 8}Mo{sub 3} phase are 7.5 at.% and 1 at.%, respectively. According to the phase-disappearing method, the maximum solubility of Al in Mo is about 16 at.%.

  8. Electron dynamics in MoS2-graphite heterostructures.

    Science.gov (United States)

    Zhang, Xinwu; He, Dawei; Yi, Lixin; Zhao, Siqi; He, Jiaqi; Wang, Yongsheng; Zhao, Hui

    2017-10-05

    The electron dynamics in heterostructures formed by multilayer graphite and monolayer or bulk MoS2 were studied by femtosecond transient absorption measurements. Samples of monolayer MoS2-multilayer graphite and bulk MoS2-multilayer graphite were fabricated by exfoliation and dry transfer techniques. Ultrafast laser pulses were used to inject electron-hole pairs into monolayer or bulk MoS2. The transfer of these photocarriers to the adjacent multilayer graphite was time resolved by measuring the differential reflection of a probe pulse. We found that photocarriers injected into monolayer MoS2 transfer to graphite on an ultrafast time scale shorter than 400 fs. Such an efficient charge transfer is key to the development of high performance optoelectronic devices with MoS2 as the light absorbing layer and graphite as electrodes. The absorption coefficient of monolayer MoS2 can be controlled by the carriers in graphite. This process can be used for interlayer coupling and control. In a bulk MoS2-graphite heterostructure, the photocarrier transfer time is about 220 ps, due to the inefficient interlayer charge transport in bulk MoS2. These results provide useful information for developing optoelectronic devices based on MoS2-graphite heterostructures.

  9. Nanostructured Mo-based electrode materials for electrochemical energy storage.

    Science.gov (United States)

    Hu, Xianluo; Zhang, Wei; Liu, Xiaoxiao; Mei, Yueni; Huang, Yunhui

    2015-04-21

    The development of advanced energy storage devices is at the forefront of research geared towards a sustainable future. Nanostructured materials are advantageous in offering huge surface to volume ratios, favorable transport features, and attractive physicochemical properties. They have been extensively explored in various fields of energy storage and conversion. This review is focused largely on the recent progress in nanostructured Mo-based electrode materials including molybdenum oxides (MoO(x), 2 ≤ x ≤ 3), dichalconides (MoX2, X = S, Se), and oxysalts for rechargeable lithium/sodium-ion batteries, Mg batteries, and supercapacitors. Mo-based compounds including MoO2, MoO3, MoO(3-y) (0 energy storage systems because of their unique physicochemical properties, such as conductivity, mechanical and thermal stability, and cyclability. In this review, we aim to provide a systematic summary of the synthesis, modification, and electrochemical performance of nanostructured Mo-based compounds, as well as their energy storage applications in lithium/sodium-ion batteries, Mg batteries, and pseudocapacitors. The relationship between nanoarchitectures and electrochemical performances as well as the related charge-storage mechanism is discussed. Moreover, remarks on the challenges and perspectives of Mo-containing compounds for further development in electrochemical energy storage applications are proposed. This review sheds light on the sustainable development of advanced rechargeable batteries and supercapacitors with nanostructured Mo-based electrode materials.

  10. Sulfur bonding in MoS2 and Co-Mo-S structures

    DEFF Research Database (Denmark)

    Byskov, Line Sjolte; Hammer, Bjørk; Nørskov, Jens Kehlet

    1997-01-01

    The structure and bonding in small MoS2 structures with and without Co is studied theoretically using self-consistent density functional theory with a non-local exchange-correlation energy. The structures model the catalysts used extensively in hydrotreating. We study in detail the structure...... and binding energies as a function of the amount of sulfur. The calculations show that extensive reconstructions occur at the two types of MoS2 edges where the sulfur dimerizes and occupies non-lattice positions. These structures are shown to be in good agreement with available experimental data. We also...

  11. Photoinduced charge transfer involving a MoMo quadruply bonded complex to a perylene diimide.

    Science.gov (United States)

    Alberding, Brian G; Brown-Xu, Samantha E; Chisholm, Malcolm H; Epstein, Arthur J; Gustafson, Terry L; Lewis, Sharlene A; Min, Yong

    2013-04-21

    Evidence, based on femtosecond transient absorption and time resolved infrared spectroscopy, is presented for photoinduced charge transfer from the Mo2δ orbital of the quadruply bonded molecule trans-Mo2(T(i)PB)2(BTh)2, where T(i)PB = 2,4,6-triisopropyl benzoate and BTh = 2,2'-bithienylcarboxylate, to di-n-octyl perylene diimide and di-n-hexylheptyl perylene diimide in thin films and solutions of the mixtures. The films show a long-lived charge separated state while slow back electron transfer, τBET ~ 500 ps, occurs in solution.

  12. Radiochemical purity of Mo and Tc solution obtained after irradiation and dissolution of Mo-100-enriched and ultra-high-purity natural Mo disks

    Energy Technology Data Exchange (ETDEWEB)

    Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, Sergey D. [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-09-01

    Four irradiations of ultra-high-purity natural Mo targets and one irradiation using 97.4% Mo-100-enriched material were performed. The purpose of these irradiations was to determine whether the presence of Sn stabilizer in the H2O2 used for the dissolution of sintered Mo disks can affect the radiochemical purity of the final K2MoO4 in 5M KOH solution. Results from radiochemical purity tests performed using thin-layer paper chromatography show that even 2– 3× excess of Sn-stabilized H2O2 typically used for dissolution of sintered Mo disks did not affect the radiochemical purity of the final product.

  13. Quality of 99mTcO4- from 99Mo Produced by 100Mo(n,2n)99Mo

    Science.gov (United States)

    Nagai, Yasuki; Nakahara, Yuto; Kawabata, Masako; Hatsukawa, Yuichi; Hashimoto, Kazuyuki; Saeki, Hideya; Motoishi, Shoji; Ohta, Akio; Shiina, Takayuki; Kawauchi, Yukimasa

    2017-05-01

    The pharmaceutical quality of 99mTc pertechnetate solution obtained from 99Mo, the 100Mo(n,2n) reaction product, was investigated for the first time with an emphasis on the nonradioactive Mo content and endotoxin concentration. They were less than the tolerance dose given in international guidelines and the established upper limit in an international pharmacopoeia, respectively. Four other quality control tests commonly used for a commercially available 99mTc pertechnetate solution also demonstrated to meet the United States Pharmacopeia requirements. The results strongly support that the thermochromatographic separation method used to separate 99mTc from 99Mo can be a promising substitute for the fission product 99Mo.

  14. Direct Reactions with MoNA-LISA

    Science.gov (United States)

    Kuchera, Anthony

    2016-03-01

    Nuclear reactions can be used to probe the structure of nuclei. Direct reactions, which take place on short time scales, are well-suited for experiments with beams of short-lived nuclei. One such reaction is nucleon knockout where a proton or neutron is removed from the incoming beam from the interaction with a target. Single nucleon knockout reactions have been used to study the single-particle nature of nuclear wave functions. A recent experiment at the National Superconducting Cyclotron Laboratory was performed to measure cross sections from single nucleon knockout reactions for several p-shell nuclei. Detection of the residual nucleus in coincidence with any gamma rays emitted from the target allowed cross sections to ground and excited states to be measured. Together with input from reaction theory, ab initio structure theories can be tested. Simultaneously the accuracy of knockout reaction models can be validated by detecting the knocked out neutron with the Modular Neutron Array and Large multi-Institutional Scintillator Array (MoNA-LISA). Preliminary results from this experiment will be shown. Knockout reactions can also be used to populate nuclei which are neutron unbound, thus emit neutrons nearly instantaneously. The structure of these nuclei, therefore, cannot be probed with gamma ray spectroscopy. However, with large neutron detectors like MoNA-LISA the properties of these short-lived nuclei are able to be measured. Recent results using MoNA-LISA to study the structure of neutron-rich nuclei will be presented. The author would like to acknowledge support from the NNSA and NSF.

  15. Facile synthesis of stable structured MoS{sub 2}-Mo-CNFs heteroarchitecture with enhanced hydrogen evolution

    Energy Technology Data Exchange (ETDEWEB)

    Mo, Qionghua [Research Institute for New Materials Technology, Chongqing University of Arts and Sciences, Chongqing 402160 (China); Faculty of Material and Energy, South West University, Chongqing 400700 (China); Yao, Yucen [Research Institute for New Materials Technology, Chongqing University of Arts and Sciences, Chongqing 402160 (China); Liu, Bitao, E-mail: liubitao007@163.com [Research Institute for New Materials Technology, Chongqing University of Arts and Sciences, Chongqing 402160 (China); Peng, Lingling; Yan, Hengqing; Hou, Zhupei; Wang, Jun [Research Institute for New Materials Technology, Chongqing University of Arts and Sciences, Chongqing 402160 (China); Lin, Yue, E-mail: linyue@ustc.edu.cn [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Anhui 230026 (China)

    2017-06-01

    3D structured MoS{sub 2} are grown in-situ on Mo particles embedded carbon nanofibers (CNFs) via a hydrothermal method. Due to this special structure, the bonding and effective electron delivery between CNFs and MoS{sub 2} are both enhanced, and which will exhibits a better hydrogen evolution activity. The onset potential of this MoS{sub 2}-Mo-CNFs catalyst will decreased to 60 mV compared to the 90 mV for the MoS{sub 2}-CNFs. And its current density nearly no change with 5000 cycles which is better than the 32.3% decrease of MoS{sub 2}-CNFs at η = 300 mV (V vs RHE). - Highlights: • Newly structured MoS{sub 2}-Mo-CNFs with effectively connection between MoS{sub 2} and CNFs successfully synthesized. • This structure can enhance the charge transfer and significantly increase electrocatalytic efficiency. • Nearly no HER activity loss after 5000 CV cycles.

  16. Effect of Mo concentration on shape and size of monolayer MoS2 crystals by chemical vapor deposition

    Science.gov (United States)

    Wang, Wenzhao; Zeng, Xiangbin; Wu, Shaoxiong; Zeng, Yang; Hu, Yishuo; Ding, Jia; Xu, Sue

    2017-10-01

    Monolayer molybdenum disulfide (MoS2), a new two-dimensional direct-bandgap semiconductor, has attracted research interests into applications in atomically thin electronics and optoelectronics. Growing monolayer MoS2 film by chemical vapor deposition is the most commonly used approach. Little is known, however, about the cause of the shape and size evolution. Here, we explore how the precursor’s concentration affects the MoS2 crystals’ shape and size. When S concentration is stable, the shape of the MoS2 domain evolves from triangle to hexagon and then truncated triangle, finally back to a triangle as the concentration of Mo elevates. Regulating the concentration of Mo leads to the controllable growth of MoS2 crystal. By controlling the concentration of Mo, we eventually synthesized over 100 µm monolayer MoS2 crystals. Our results are a significant step forward in realizing the ultimate promise of large atomic MoS2 monolayer crystals for flexible, electronic, optoelectronic devices.

  17. ¿Cómo hacerse arquitecto?

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1961-03-01

    Full Text Available He conocido muchos profesores maravillosos esparcidos por las Escuelas de Arquitectura de todo el mundo, y que constituyen magníficos ejemplos de seres humanos totalmente entregados a la enseñanza, en continua lucha con los alumnos, dotados de una constancia y tenacidad compleja. Junto con sus alumnos, ellos saben, aunque ellos no pueden, que deben trabajar, principalmente, sobre el objeto real de estudio: el cliente de carne y hueso. Más tarde, en la vida profesional, se encontrará con él y apreciará cómo siente su confianza o, por el contrario, duda de sus criterios.

  18. MoRM and Future Memories

    DEFF Research Database (Denmark)

    Rehder, Mads Middelboe; Ostrowski, Kasper

    for the experimental workshop we lunged into a process of devising both an interactive exhibition and an installation which explored the ‘big data’ citizens regularly produce in their everyday lives and how this data might be archived, packaged, and recycled - or even forgotten, primarily within social media. We...... wanted to explore what our daily routines connected to social media and sorting our data meant for the way we shape our memories, and therefore the traces of future memories. In this chapter we follow the trajectory of the exhibition entitled ‘MoRM’ (Museum of Random Memories)....

  19. Na2MoO2As2O7

    Directory of Open Access Journals (Sweden)

    Raja Jouini

    2012-12-01

    Full Text Available Disodium molybdenum dioxide diarsenate, Na2MoO2As2O7, has been synthesized by a solid-state reaction. The structure is built up from MoAs2O12 linear units sharing corners to form a three-dimensional framework containing tunnels running along the a-axis direction in which the Na+ cations are located. In this framework, the AsV atoms are tetrahedrally coordinated and form an As2O7 group. The MoVI atom is displaced from the center of an octahedron of O atoms. Two Na+ cations are disordered about inversion centres. Structural relationships between different compounds: A2MoO2As2O7 (A = K, Rb, AMOP2O7 (A = Na, K, Rb; M = Mo, Nb and MoP2O7 are discussed.

  20. The synthesis of hierarchical nanostructured MoS{sub 2}/Graphene composites with enhanced visible-light photo-degradation property

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yongjie, E-mail: zhaoyjpeace@gmail.com [Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081 (China); Zhang, Xiaowei; Wang, Chengzhi [Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081 (China); Zhao, Yuzhen; Zhou, Heping [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084 (China); Li, Jingbo; Jin, HaiBo [Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing, 100081 (China)

    2017-08-01

    Graphical abstract: Introducing graphene layer into MoS{sub 2} could construct the steady hierarchical structure which could efficiently separate the photo-induced electrons so as to enhance the photo- degradation behavior. - Highlights: • The MoS{sub 2} and MoS{sub 2}/Graphene nanocomposite have been synthesized via a solvothermal process. • The scrolled nanosheets of MoS{sub 2} combining with interconnected graphene network promoted the formation of steady hierarchical architecture. • Comparing with MoS{sub 2}, the hierarchical MoS{sub 2}/Graphene nanocomposite achieved relatively higher degradation rate. • The synergistic effect mechanism for excellent photo-degradation activity was proposed. - Abstract: Novel two-dimensional materials with a layered structure are of special interest for a variety of promising applications. Herein, MoS{sub 2} and MoS{sub 2}/Graphene nanocomposite with hierarchical nanostructure were successfully synthesized employing a one-step hydrothermal method. Photo-degradation of methylene blue (MB) and rhodamine (RHB) were adopted to assess the photo-degradation ability of the products. Comparing with bare MoS{sub 2}, the hierarchical MoS{sub 2}/Graphene nanocomposite achieved relatively higher degradation rate of 99% in 28 min for MB as well in 50 min for RHB. These results verified that this proposed hierarchical nanocomposite is a good photo-degradation semiconductor. The excellent performance was mainly ascribed to the synergistic effect of MoS{sub 2} and graphene layers. The MoS{sub 2} possessing a band gap of 1.9 eV would provide abundant electron-hole pairs. The graphene layers with excellent electro-conductivity could realize the quick transport of electrons via its extended π-conjugation structure, consequently benefiting the separation of photo-generated carriers. These findings indicate that the graphene layer is a promising candidate as a co-catalyst for MoS{sub 2} photo-catalyst, and also provide useful information

  1. IEA Mobility Model (MoMo) and its use in the ETP 2008

    Energy Technology Data Exchange (ETDEWEB)

    Fulton, Lew; Cazzola, Pierpaolo; Cuenot, Francois [International Energy Agency, Energy Technology Policy Division, 9, Rue de la Federation, Paris 75015 (France)

    2009-10-15

    The IEA published 'Energy Technology Perspectives' (ETP) in June 2008. That document reports on IEA scenarios for baseline and low-CO{sub 2} alternative scenarios to 2050, across the energy economy. The study included creating scenarios for transport, using the IEA Mobility Model (MoMo). This paper reports on the transport-related ETP scenarios and describes the model used in the analysis. According to the ETP Baseline scenario, world transport energy use and CO{sub 2} emissions will more than double by 2050. In the most challenging scenario, called 'BLUE', transport emissions are reduced by 70% in 2050 compared to their baseline level in that year (and about 25% below their 2005 levels). There are several versions of the BLUE scenario, but all involve: a 50% or greater improvement in LDV efficiency, 30-50% improvement in efficiency of other modes (e.g. trucks, ships and aircraft), 25% substitution of liquid fossil fuels by biofuels, and considerable penetration of electric and/or fuel-cell vehicles. In the second half of this paper, an overview of the MoMo model is provided. Details on the complete analysis are contained in the ETP 2008 document, available at www.iea.org. Details of the LDV fuel economy analysis are contained in a separate paper in this collection. (author)

  2. Intermediate report of MoReMo. Modelling resilience for maintenance and outage

    Energy Technology Data Exchange (ETDEWEB)

    Oedewald, P.; Macchi, L. (VTT Technical Research Centre of Finland (Finland)); Axelsson, C. (Ringhals AB, Vattenfall AB (Sweden)); Eitrheim, M.H.R. (Institute for Energy Technology (Norway))

    2012-02-15

    Resilience Engineering (RE) is a new approach to safety that helps organisations and individuals adapt to unforeseen events and long-term changes. Such an approach is needed by nuclear power plants (NPPs) as they face demanding modification projects, high staff turnover and increased pressures to maintain and improve safety. The goal of the Modelling Resilience for Maintenance and Outage (MoReMO) project is to develop and test models and methods to identify and analyse resilience in safety-critical activities in natural everyday settings. In 2011, we have applied four approaches in different case studies: Organisational Core Task modelling (OCT), Functional Resonance Analysis Method (FRAM), Efficiency Thoroughness Trade-Off (ETTO) analysis, and Work Practice and Culture Characterisation. The project has collected data through observations, interviews and document reviews at two NPPs. Together, the four approaches have provided valuable insights for understanding the rationale behind work practices, their effects on safety, and the support of flexibility and adaptability. In 2012, the MoReMO project will complete the data collection and integrate results on how resilience can be operationalized in practical safety management tools for the companies. (Author)

  3. Synthesis and reactivity of dimolybdathiaborane cluster [(Cp Mo) 2 B ...

    Indian Academy of Sciences (India)

    Chemistry and reactivity of dimolybdathiaborane, [(Cp∗Mo)2B4SH6], 1, obtained from the reaction of 2-mercaptobenzothiazole, [Cp∗MoCl4] and [LiBH4.thf], has been explored with dinuclear metal carbonyl [Fe2(CO)9]. As a result, reaction of 1 with [Fe2(CO)9] yielded heterometallathiaborane, [(Cp∗Mo)2B4H6SFe(CO)3], ...

  4. Folded MoS2 layers with reduced interlayer coupling

    OpenAIRE

    Castellanos-Gomez, Andres; van der Zant, Herre S. J.; Steele, Gary A.

    2013-01-01

    We study molybdenum disulfide (MoS2) structures generated by folding single- and bilayer MoS2 flakes. We find that this modified layer stacking leads to a decrease in the interlayer coupling and an enhancement of the photoluminescence emission yield. We additionally find that folded single-layer MoS2 structures show a contribution to photoluminescence spectra of both neutral and charged excitons, which is a characteristic feature of single-layer MoS2 that has not been observed in multilayer M...

  5. Synthesis of nanometre-thick MoO3 sheets

    Science.gov (United States)

    Kalantar-Zadeh, Kourosh; Tang, Jianshi; Wang, Minsheng; Wang, Kang L.; Shailos, Alexandros; Galatsis, Kosmas; Kojima, Robert; Strong, Veronica; Lech, Andrew; Wlodarski, Wojtek; Kaner, Richard B.

    2010-03-01

    The formation of MoO3 sheets of nanoscale thickness is described. They are made from several fundamental sheets of orthorhombic α-MoO3, which can be processed in large quantities via a low cost synthesis route that combines thermal evaporation and mechanical exfoliation. These fundamental sheets consist of double-layers of linked distorted MoO6 octahedra. Atomic force microscopy (AFM) measurements show that the minimum resolvable thickness of these sheets is 1.4 nm which is equivalent to the thickness of two double-layers within one unit cell of the α-MoO3 crystal.

  6. Infrared light gated MoS₂ field effect transistor.

    Science.gov (United States)

    Fang, Huajing; Lin, Ziyuan; Wang, Xinsheng; Tang, Chun-Yin; Chen, Yan; Zhang, Fan; Chai, Yang; Li, Qiang; Yan, Qingfeng; Chan, H L W; Dai, Ji-Yan

    2015-12-14

    Molybdenum disulfide (MoS₂) as a promising 2D material has attracted extensive attentions due to its unique physical, optical and electrical properties. In this work, we demonstrate an infrared (IR) light gated MoS₂ transistor through a device composed of MoS₂ monolayer and a ferroelectric single crystal Pb(Mg(1/3)Nb(2/3))O₃-PbTiO₃ (PMN-PT). With a monolayer MoS₂ onto the top surface of (111) PMN-PT crystal, the drain current of MoS₂ channel can be modulated with infrared illumination and this modulation process is reversible. Thus, the transistor can work as a new kind of IR photodetector with a high IR responsivity of 114%/Wcm⁻². The IR response of MoS₂ transistor is attributed to the polarization change of PMN-PT single crystal induced by the pyroelectric effect which results in a field effect. Our result promises the application of MoS₂ 2D material in infrared optoelectronic devices. Combining with the intrinsic photocurrent feature of MoS₂ in the visible range, the MoS₂ on ferroelectric single crystal may be sensitive to a broadband wavelength of light.

  7. Dynamic coercivity of Mo-doped FINEMETs

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Srimoy; Mandal, Kalyan; Sakar, Debashis [S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098 (India); Cremaschi, Victoria J. [Lab. de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires-CONICET, Paseo Colon 850, C1063ACV Buenos Aires (Argentina); Member of CONICET (Argentina); Silveyra, Josefina M., E-mail: jsilveyra@fi.uba.a [Lab. de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires-CONICET, Paseo Colon 850, C1063ACV Buenos Aires (Argentina)

    2011-05-01

    The structure and the dc magnetic behavior of FINEMET-type alloys doped with molybdenum have been recently reported. Most commercial applications of these materials are, however, not at dc but at high magnetizing frequencies. Therefore, we report a study of the frequency dependence of coercivity, H{sub c}(f), in amorphous and nanocrystalline ribbons of composition Fe{sub 73.5}Si{sub 13.5}Nb{sub 3-x}Mo{sub x}B{sub 9}Cu{sub 1} (x=0, 1.5 and 3) in the frequency range from 0.5 to 1.3 kHz. The nature of H{sub c}(f) measurements revealed the influence of eddy currents in the magnetization of samples. The frequency dependence of coercivity did not vary with the molybdenum content in the amorphous samples. All the alloys exhibited a systematic improvement in the coercivity after nanocrystallization and it was found that this improvement was better as more Nb was replaced by Mo.

  8. A Bayesian network model for predicting aquatic toxicity mode ...

    Science.gov (United States)

    The mode of toxic action (MoA) has been recognized as a key determinant of chemical toxicity but MoA classification in aquatic toxicology has been limited. We developed a Bayesian network model to classify aquatic toxicity mode of action using a recently published dataset containing over one thousand chemicals with MoA assignments for aquatic animal toxicity. Two dimensional theoretical chemical descriptors were generated for each chemical using the Toxicity Estimation Software Tool. The model was developed through augmented Markov blanket discovery from the data set with the MoA broad classifications as a target node. From cross validation, the overall precision for the model was 80.2% with a R2 of 0.959. The best precision was for the AChEI MoA (93.5%) where 257 chemicals out of 275 were correctly classified. Model precision was poorest for the reactivity MoA (48.5%) where 48 out of 99 reactive chemicals were correctly classified. Narcosis represented the largest class within the MoA dataset and had a precision and reliability of 80.0%, reflecting the global precision across all of the MoAs. False negatives for narcosis most often fell into electron transport inhibition, neurotoxicity or reactivity MoAs. False negatives for all other MoAs were most often narcosis. A probabilistic sensitivity analysis was undertaken for each MoA to examine the sensitivity to individual and multiple descriptor findings. The results show that the Markov blanket of a structurally

  9. Corrosion behavior of magnetron sputter-deposited (Mo/0.6/Ru/0.4/)82B18 and Mo82B18 amorphous metal films

    Science.gov (United States)

    Williams, R. M.; Thakoor, A. P.; Khanna, S. K.; Johnson, W. L.

    1984-01-01

    Amorphous metallic films of Mo49Ru33B18 and Mo82B18 have been prepared by magnetron sputtering, and their corrosion behavior was investigated and compared with amorphous liquid-quenched Mo49Ru33B18 and crystalline Mo i acidic and basic solutions. Sputtered Mo49Ru33B18 showed lower corrosion rates compared with liquid-quenched Mo49Ru33B18, owing to the superior surface smoothness and uniformity of the former. Amorphous Mo82B18 showed low corrosion rates in both acidic and basic aqueous solutions. Comparison of the corrosion properties of Mo49Ru33B18 with Mo82B18 and Mo demonstrates the roles of the alloys' constituents. Ru significantly extends the passive region to high-anodic potentials, but, at less-anodic potentials, Mo82B18 has the lowest corrosion rate.

  10. Page 1 306 R Viswanathan 10,000 o CrMoV, MG (ductile) e CrMoV ...

    Indian Academy of Sciences (India)

    the International Organization for Standardization's [ISO's] Larson–Miller data) is used as the reference condition for calculating the tr. In reality, as the component softens, the applicable Larson–Miller curve is continuously changing in such a way. O CrMoV, heat MG (ductile). © CrMoV, heat FW (brittle). C 2-1/4 Cr-1Mo, heat ...

  11. Social networking in nursing education: integrative literature review

    OpenAIRE

    Luciana Emi Kakushi; Yolanda Dora Martinez Évora

    2016-01-01

    Abstract Objective: to identify the use of social networking in nursing education. Method: integrative literature review in the databases: LILACS, IBECS, Cochrane, BDENF, SciELO, CINAHL, Scopus, PubMed, CAPES Periodicals Portal and Web of Science, using the descriptors: social networking and nursing education and the keywords: social networking sites and nursing education, carried out in April 2015. Results: of the 489 articles found, only 14 met the inclusion and exclusion criteria. Mo...

  12. Intercalation of Si between MoS2 layers

    NARCIS (Netherlands)

    van Bremen, Rik; Yao, Qirong; Banerjee, Soumya; Cakir, Deniz; Oncel, Nuri; Zandvliet, Harold J.W.

    2017-01-01

    We report a combined experimental and theoretical study of the growth of sub-monolayer amounts of silicon (Si) on molybdenum disulfide (MoS2). At room temperature and low deposition rates we have found compelling evidence that the deposited Si atoms intercalate between the MoS2 layers. Our evidence

  13. MoS2 Surface Structure Tailoring via Carbonaceous Promoter

    Science.gov (United States)

    Shi, Yumeng; Li, Henan; Wong, Jen It; Zhang, Xiaoting; Wang, Ye; Song, Huaihe; Yang, Hui Ying

    2015-01-01

    Atomically thin semiconducting transition-metal dichalcogenides have been attracting lots of attentions, particularly, molybdenum disulfide (MoS2) monolayers show promising applications in field effect transistors, optoelectronics and valleytronics. However, the controlled synthesis of highly crystalline MoS2 remain a challenge especially the systematic approach to manipulate its structure and morphology. Herein, we report a method for controlled synthesis of highly crystalline MoS2 by using chemical vapor deposition method with carbonaceous materials as growth promoter. A uniform and highly crystalline MoS2 monolayer with the grain size close to 40 μm was achieved. Furthermore, we extend the method to the manipulation of MoS2 morphology, flower-shape vertical grown MoS2 layers were obtained on growth promoting substrates. This simple approach allows an easy access of highly crystalline MoS2 layers with morphology tuned in a controllable manner. Moreover, the flower-shape MoS2 grown on graphene oxide film used as an anode material for lithium-ion batteries showed excellent electrochemical performance. PMID:25994238

  14. Structure, morphology and corrosion resistance of Ni–Mo+PTh ...

    Indian Academy of Sciences (India)

    Ni–Mo+PTh composite coatings were prepared from nickel–molybdenum galvanic bath with the addition of thiophene (Th) and HClO4 as result of two processes: induced Ni–Mo alloy deposition and PTh polymerization. A scanning electron microscope was used for surface morphology characterization of the coatings.

  15. Phosphorus in Sintered Steels: Interaction of Phosphorus with Mo

    Science.gov (United States)

    Danninger, H.; Üregen, B.

    2016-10-01

    Phosphorus as an alloy element is quite common in powder metallurgy, the contents industrially used being markedly higher than those present in wrought steels. However, embrittlement effects are reported also for sintered steels, in part depending on the alloy elements present. In this study, the influence of phosphorus addition on the mechanical properties of PM steels alloyed with Mo, as the most common VI group element in sintered steels, was investigated. PM steels of the type Fe-x%Mo-0.7%Cy% P were manufactured with varying contents of Mo and P, respectively. It showed that P activates sintering also in these materials and enhances Mo homogenization, but there is in fact a risk of embrittlement in these steels that however strongly depends on the combination of Mo and P in the materials: If a critical level is exceeded, embrittlement is observed. At low Mo contents, higher P concentrations are acceptable and vice versa, but e.g. in a material Fe-1.5%Mo-0.7%C-0.45%P, pronounced intergranular embrittlement occurs, further enhanced by sinter hardening effects. This undesirable phenomenon is more pronounced at higher sintering temperatures and in case of faster heating/cooling; it was observed both in materials prepared from mixed and prealloyed powders, respectively. This typical intergranular failure observed with embrittled specimens, in particular after impact testing, indicates the precipitation of brittle phases at the grain boundaries, apparently when exceeding the solubility product between Mo and P.

  16. Chemical sensitivity of Mo gate Mos capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Lombardi, R.M.; Aragon, R. [Laboratorio de Peliculas delgadas, Facultad de Ingenieria, Paseo Colon 850, 1063, Buenos Aires (Argentina)

    2006-07-01

    Mo gate Mos capacitors exhibit a negative shift of their C-V characteristic by up to 240 mV, at 125 C, in response to 1000 ppm hydrogen, in controlled nitrogen atmospheres. The experimental methods for obtaining capacitance and conductance, as a function of polarisation voltage, as well as the relevant equivalent circuits are reviewed. The single-state interface state density, at the semiconductor-dielectric interface, decreases from 2.66 x 10{sup 11} cm{sup -2} e-v{sup -1}, in pure nitrogen, to 2.5 x 10{sup 11} cm{sup -2} e-v{sup -1} in 1000 ppm hydrogen in nitrogen mixtures, at this temperature. (Author)

  17. ¿Cómo salir del liberalismo?

    Directory of Open Access Journals (Sweden)

    Lenin Flórez

    2001-01-01

    Full Text Available Alain Touraine ¿Cómo salir del Liberalismo? Piadós, Bacelona, 1999, 123 páginas. El libro parece circunscribirse al actual contexto político de Francia, que el autor considera como una coyuntura de salida del liberalismo. Su tema central gira alrededor de entender la democracia en este periodo y un proyecto político de más largo alcance. Sin embargo, sabemos que tiene serias investigaciones sobre la realidad latinoamericana, lo que nos indica que su temática rebasa el mundo europeo. Sin duda, el texto que reseñamos tiene un carácter crítico y sus planteamientos suscitan la controversia teórica.

  18. Structural studies of the molybdenum site in the MoFe protein and it FeMo cofactor by EXAFS

    Energy Technology Data Exchange (ETDEWEB)

    Conradson, S.D.; Burgess, B.K.; Newton, W.E.; Mortenson, L.E.; Hodgson, K.O.

    1987-11-25

    Nitrogenase is a complex bacterial enzyme system that is responsible for the conversion of atmospheric N/sub 2/ to ammonia. The structure and function of molybdenum in the MoFe protein of this system has been the subject of a number of investigations, including the use of X-ray absorption spectroscopy. This paper reports the results of the authors recent studies on several states of the MoFe protein and its FeMo cofactor (which is extruded by treatment with N-methylformamide). Mo K-edge (XANES) and extended fine structure (EXAFS) spectra have been recorded to high energies above the absorption edge with excellent signal-to-nose on the semireduced form of the MoFe protein from both Clostridium pasteurianum and Azotobacter vinelandii and on the as isolated FeMo-co and FeMo-co treated with benzenethiol and with benzeneselenol. In all of the states studied, EXAFS results reveal that the Mo is in an environment that contains two or three oxygen (or nitrogen) atoms at 2.10-2.12 A, three to five S atoms at 2.37 A, and three to four Fe atoms at 2.68-2.70 A. The numbers of these ligands change upon removal of the cofactor from the protein as discussed in the paper. For FeMo-co, comparisons also show that thil/selenol is not binding directly to the Mo site. The results of these EXAFS (and their XANES published earlier) definitely show the presence of several low-Z ligands and are not compatible with a tetrahedral arrangement of only nearest S neighbors at the Mo site.

  19. Physical Activity of German Children and Adolescents 2003–2012: The MoMo-Study

    Science.gov (United States)

    Henn, Annette; Albrecht, Claudia; Woll, Alexander

    2017-01-01

    Organized and unorganized physical activity (PA) hold an important role in the daily life of children and adolescents. Regular representative tracking of PA in different settings is important to evaluate social trends and implemented interventions. In this paper, representative PA data of German children and adolescents from the MoMo Baseline-Study (2004, n = 4528) are compared to those of Wave 1 (2010, n = 3994). Participants aged 4–17 were drawn out of 167 sample points in Germany and the data was weighted to ensure representativeness. PA was measured via questionnaire and was differentiated between organized (sports clubs and schools) and unorganized (unorganized sports and playing outside). Organized PA in extracurricular activities and sports clubs increased by eight percent, while unorganized PA decreased by seven percent. In addition to sports clubs, schools became a more prevalent setting for participation in physical activity in Germany. PMID:29137127

  20. Physical Activity of German Children and Adolescents 2003-2012: The MoMo-Study.

    Science.gov (United States)

    Schmidt, Steffen C E; Henn, Annette; Albrecht, Claudia; Woll, Alexander

    2017-11-11

    Organized and unorganized physical activity (PA) hold an important role in the daily life of children and adolescents. Regular representative tracking of PA in different settings is important to evaluate social trends and implemented interventions. In this paper, representative PA data of German children and adolescents from the MoMo Baseline-Study (2004, n = 4528) are compared to those of Wave 1 (2010, n = 3994). Participants aged 4-17 were drawn out of 167 sample points in Germany and the data was weighted to ensure representativeness. PA was measured via questionnaire and was differentiated between organized (sports clubs and schools) and unorganized (unorganized sports and playing outside). Organized PA in extracurricular activities and sports clubs increased by eight percent, while unorganized PA decreased by seven percent. In addition to sports clubs, schools became a more prevalent setting for participation in physical activity in Germany.

  1. Physical Activity of German Children and Adolescents 2003–2012: The MoMo-Study

    Directory of Open Access Journals (Sweden)

    Steffen C. E. Schmidt

    2017-11-01

    Full Text Available Organized and unorganized physical activity (PA hold an important role in the daily life of children and adolescents. Regular representative tracking of PA in different settings is important to evaluate social trends and implemented interventions. In this paper, representative PA data of German children and adolescents from the MoMo Baseline-Study (2004, n = 4528 are compared to those of Wave 1 (2010, n = 3994. Participants aged 4–17 were drawn out of 167 sample points in Germany and the data was weighted to ensure representativeness. PA was measured via questionnaire and was differentiated between organized (sports clubs and schools and unorganized (unorganized sports and playing outside. Organized PA in extracurricular activities and sports clubs increased by eight percent, while unorganized PA decreased by seven percent. In addition to sports clubs, schools became a more prevalent setting for participation in physical activity in Germany.

  2. Rocking disc electro-deposition of copper films on Mo/MoSe{sub 2} substrates

    Energy Technology Data Exchange (ETDEWEB)

    Cummings, Charles Y.; Frith, Paul E. [Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); Zoppi, Guillaume; Forbes, Ian [Northumbria Photovoltaics Applications Centre, Northumbria University, NE1 8ST (United Kingdom); Rogers, Keith D. [Cranfield Health, Cranfield University, Shrivenham Campus, Swindon, SN6 8LA (United Kingdom); Lane, David W. [Department of Applied Science, Security and Resilience, Cranfield University, Shrivenham, Swindon, SN6 8LA (United Kingdom); Marken, Frank, E-mail: F.Marken@bath.ac.uk [Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)

    2011-08-31

    A novel electro-deposition method based on a rocking disc system with {pi}/3 amplitude and variable frequency is introduced. Uniform copper films were deposited from a 0.1 M CuSO{sub 4}/3.0 M NaOH/0.2 M sorbitol bath directly onto 12.1 cm{sup 2} Mo/MoSe{sub 2} substrates with X-ray diffraction showing a thickness variation of {+-}5% over this area. Investigation of the mass transport conditions suggests (i) uniform diffusion over the sample, (ii) a rate of mass transport proportional to the square root of the rocking rate, and (iii) turbulent conditions, which are able to dislodge gas bubbles during electro-deposition.

  3. Fission-Produced99Mo Without a Nuclear Reactor.

    Science.gov (United States)

    Youker, Amanda J; Chemerisov, Sergey D; Tkac, Peter; Kalensky, Michael; Heltemes, Thad A; Rotsch, David A; Vandegrift, George F; Krebs, John F; Makarashvili, Vakho; Stepinski, Dominique C

    2017-03-01

    99 Mo, the parent of the widely used medical isotope 99m Tc, is currently produced by irradiation of enriched uranium in nuclear reactors. The supply of this isotope is encumbered by the aging of these reactors and concerns about international transportation and nuclear proliferation. Methods: We report results for the production of 99 Mo from the accelerator-driven subcritical fission of an aqueous solution containing low enriched uranium. The predominately fast neutrons generated by impinging high-energy electrons onto a tantalum convertor are moderated to thermal energies to increase fission processes. The separation, recovery, and purification of 99 Mo were demonstrated using a recycled uranyl sulfate solution. Conclusion: The 99 Mo yield and purity were found to be unaffected by reuse of the previously irradiated and processed uranyl sulfate solution. Results from a 51.8-GBq 99 Mo production run are presented. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

  4. Rhenium-doped MoS2 films

    Science.gov (United States)

    Hallam, Toby; Monaghan, Scott; Gity, Farzan; Ansari, Lida; Schmidt, Michael; Downing, Clive; Cullen, Conor P.; Nicolosi, Valeria; Hurley, Paul K.; Duesberg, Georg S.

    2017-11-01

    Tailoring the electrical properties of transition metal dichalcogenides by doping is one of the biggest challenges for the application of 2D materials in future electronic devices. Here, we report on a straightforward approach to the n-type doping of molybdenum disulfide (MoS2) films with rhenium (Re). High-Resolution Scanning Transmission Electron Microscopy and Energy-Dispersive X-ray spectroscopy are used to identify Re in interstitial and lattice sites of the MoS2 structure. Hall-effect measurements confirm the electron donating influence of Re in MoS2, while the nominally undoped films exhibit a net p-type doping. Density functional theory (DFT) modelling indicates that Re on Mo sites is the origin of the n-type doping, whereas S-vacancies have a p-type nature, providing an explanation for the p-type behaviour of nominally undoped MoS2 films.

  5. Development and design for Mo-production facility in JMTR

    Energy Technology Data Exchange (ETDEWEB)

    Iimura, Koichi; Hosokawa, Jinsaku; Izumo, Hironobu; Hori, Naohiko; Nakagawa, Tetsuya; Kanno, Masaru; Kawamura, Hiroshi [Japan Atomic Energy Agency (JAEA) Ibaraki, (Japan)

    2008-11-15

    At Oarai Research and Development Center, Japan Atomic Energy Agency (JAEA) being advanced is the plan of refurbishing Japan materials Testing Reactor (JMTR) to start the operation in FY2011. As one of effective use of the JMTR, JAEA has a plan to produce {sup 99}Mo, a parent nuclide of {sup 99m}Tc. {sup 99m}Tc is most commonly used as a radiopharmaceutical in the field of nuclear medicine. Currently, the supplying of {sup 99}Mo depends only on imports from foreign countries, therefore JAEA is aiming at domestic production of a part of {sup 99}Mo in cooperation with industrial users. As JAEA's activities, mentioned are the process, the selection and fabric of the irradiation facilities for {sup 99}Mo production, the technical study of commercializing equipment after irradiation, and the cost evaluation for {sup 99}Mo.

  6. Development and design for Mo production facility in JMTR

    Energy Technology Data Exchange (ETDEWEB)

    Iimura, Koichi; Hosokawa, Jinsaku; Izumo, Hironobu; Hori, Naohiko; Nakagawa, Tetsuya; Kanno, Masaru; Kawamura, Hiroshi [Japan Atomic Energy Agency, Ibaraki Ken (Japan)

    2008-11-15

    At Oarai Research and Development Center, Japan Atomic Energy Agency (JAEA) being advanced is the plan of refurbishing Japan Materials Testing Reactor (JMTR) to start the operation in FY 2011. As one of effective use of the JMTR, JAEA has a plan to product {sup 99}Mo, a parent nuclide of {sup 99m}Tc. {sup 99m}Tc is most commonly used as a radiopharmaceutical in the field of nuclear medicine. Currently the supplying of {sup 99}Mo depends only on imports from foreign countries, therefore JAEA is aiming at domestic production of a part of {sup 99}Mo in cooperation with industrial users. As JAEA's activities, mentioned are the process, the selection and fabric of the irradiation facilities for {sup 99}Mo production, the technical study of commercializing equipment after irradiation, and the cost evaluation for {sup 99}Mo production.

  7. MoS2-supported gold nanoparticle for CO hydrogenation

    Science.gov (United States)

    Rawal, Takat B.; Le, Duy; Rahman, Talat S.

    2017-10-01

    Employing dispersion-corrected density functional theory, we examine the geometry, electronic structure, and reactivity of 13-atom Au nanoparticle supported on defect-laden single-layer MoS2. The planar structure of Au13 favored in isolated phase, transforms into the three-dimensional structure when supported on MoS2. We find that charge is transferred from MoS2 to Au13, and that the electron density is also distributed away from the Au13/MoS2 interfacial region—making Au sites away from the interface catalytically active. Owing to effect of the support, the Au d states become narrower, and the frontier states appear close to the Fermi level. Consequently, in contrast to the reactivity of Au13/TiO2 toward methanol decomposition, Au13/MoS2 offers excellent activity toward methanol synthesis, as demonstrated here, via CO hydrogenation.

  8. Effect of Ni on the characteristics and hydrogenation activity of sulfide Mo/{gamma}-Al{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Schachtl, E.; Wuttke, E.; Gutierrez, O.Y.; Lercher, J.A. [Technische Univ. Muenchen, Garching (Germany). Dept. of Chemistry and Catalysis Research Center

    2012-07-01

    The hydrogenation of phenanthrene was explored on sulfide Mo/{gamma}-Al{sub 2}O{sub 3} catalysts promoted with increasing concentrations of Ni. The characterization of the materials was done by N{sub 2}-physisorption, X-ray diffraction, transmission electron microscopy, temperature programmed sulfidation and NO adsorption experiments. Increasing loading of Ni improves the dispersion of MoS{sub 2} species; however, at Ni/(Mo+Ni) molar ratio higher than 0.5, segregation of Ni-sulfides is observed. The presence of Ni also facilitates the sulfidation of oxidic catalyst precursors by lowering the reduction temperature of Mo species. In the sulfide catalysts, Ni changes the structure of MoS{sub 2} leading to shorter slabs with higher stacking degree than on Mo/{gamma}-Al{sub 2}O{sub 3}, and increases the concentration of coordinatively unsaturated sites. The kinetic results (increased hydrogenation rate and changed reaction network in the presence of Ni) suggest that a highly active kind of active site is created by Ni promotion. (orig.)

  9. Final report of MoReMO 2011-2012. Modelling resilience for maintenance and outage

    Energy Technology Data Exchange (ETDEWEB)

    Gotcheva, N.; Macchi, L.; Oedewald, P. [Technical Research Centre of Finland (VTT), Espoo (Finland); Eitrheim, M.H.R. [Institute for Energy Technology (IFE) (Norway); Axelsson, C.; Reiman, T.; Pietikaeinen, E. [Ringhals AB (NPP), Vattenfall AB (Sweden)

    2013-04-15

    The project Modelling Resilience for Maintenance and Outage (MoReMO) represents a two-year joint effort by VTT Technical Research Centre of Finland, Institute for Energy Technology (IFE, Norway) and Vattenfall (Sweden) to develop and test new approaches for safety management. The overall goal of the project was to present concepts on how resilience can be operationalized and built in a safety critical and socio-technical context. Furthermore, the project also aimed at providing guidance for other organizations that strive to develop and improve their safety performance in a business driven industry. We have applied four approaches in different case studies: Organisational Core Task modelling (OCT), Functional Resonance Analysis Method (FRAM), Efficiency Thoroughness Trade-Off (ETTO) analysis, and Work Practice and Culture Characterisation. During 2011 and 2012 the MoReMO project team has collected data through field observations, interviews, workshops, and document analysis on the work practices and adjustments in maintenance and outage in Nordic NPPs. The project consisted of two sub-studies, one focused on identifying and assessing adjustments and supporting resilient work practices in maintenance activities, while the other focused on handling performance trade-offs in maintenance and outage, as follows: A. Adjustments in maintenance work in Nordic nuclear power plants (VTT and Vattenfall). B. Handling performance trade-offs - the support of adaptive capacities (IFE and Vattenfall). The historical perspective of maintenance and outage management (Chapter 1.1) was provided by Vattenfall. Together, the two sub-studies have provided valuable insights for understanding the rationale behind work practices and adjustments, their effects on resilience, promoting flexibility and balancing between flexibility and reliability. (Author)

  10. Intercalation of Si between MoS2 layers.

    Science.gov (United States)

    van Bremen, Rik; Yao, Qirong; Banerjee, Soumya; Cakir, Deniz; Oncel, Nuri; Zandvliet, Harold J W

    2017-01-01

    We report a combined experimental and theoretical study of the growth of sub-monolayer amounts of silicon (Si) on molybdenum disulfide (MoS2). At room temperature and low deposition rates we have found compelling evidence that the deposited Si atoms intercalate between the MoS2 layers. Our evidence relies on several experimental observations: (1) Upon the deposition of Si on pristine MoS2 the morphology of the surface transforms from a smooth surface to a hill-and-valley surface. The lattice constant of the hill-and-valley structure amounts to 3.16 Å, which is exactly the lattice constant of pristine MoS2. (2) The transitions from hills to valleys are not abrupt, as one would expect for epitaxial islands growing on-top of a substrate, but very gradual. (3) I(V) scanning tunneling spectroscopy spectra recorded at the hills and valleys reveal no noteworthy differences. (4) Spatial maps of dI/dz reveal that the surface exhibits a uniform work function and a lattice constant of 3.16 Å. (5) X-ray photo-electron spectroscopy measurements reveal that sputtering of the MoS2/Si substrate does not lead to a decrease, but an increase of the relative Si signal. Based on these experimental observations we have to conclude that deposited Si atoms do not reside on the MoS2 surface, but rather intercalate between the MoS2 layers. Our conclusion that Si intercalates upon the deposition on MoS2 is at variance with the interpretation by Chiappe et al. (Adv. Mater.2014, 26, 2096-2101) that silicon forms a highly strained epitaxial layer on MoS2. Finally, density functional theory calculations indicate that silicene clusters encapsulated by MoS2 are stable.

  11. Environmentally Resistant Mo-Si-B-Based Coatings

    Science.gov (United States)

    Perepezko, J. H.; Sossaman, T. A.; Taylor, M.

    2017-06-01

    High-temperature applications have demonstrated aluminide-coated nickel-base superalloys to be remarkably effective, but are reaching their service limit. Alternate materials such as refractory (e.g., W, Mo) silicide alloys and SiC composites are being considered to extend high temperature capability, but the silica surfaces on these materials require coatings for enhanced environmental resistance. This can be accomplished with a Mo-Si-B-based coating that is deposited by a spray deposition of Mo followed by a chemical vapor deposition of Si and B by pack cementation to develop an aluminoborosilica surface. Oxidation of the as-deposited (Si + B)-pack coatings proceeds with partial consumption of the initial MoSi2 forming amorphous silica. This Si depletion leads to formation of a B-saturated Mo5Si3 (T1) phase. Reactions between the Mo and the B rich phases develop an underlying Mo5SiB2 (T2) layer. The T1 phase saturated with B has robust oxidation resistance, and the Si depletion is prevented by the underlying diffusion barrier (T2). Further, due to the natural phase transformation characteristics of the Mo-Si-B system, cracks or scratches to the outer silica and T1 layers can be repaired from the Si and B reservoirs of T2 + MoB layer to yield a self-healing characteristic. Mo-Si-B-based coatings demonstrate robust performance up to at least 1700 °C not only to the rigors of elevated temperature oxidation, but also to CMAS attack, hot corrosion attack, water vapor and thermal cycling.

  12. Declarative Networking

    CERN Document Server

    Loo, Boon Thau

    2012-01-01

    Declarative Networking is a programming methodology that enables developers to concisely specify network protocols and services, which are directly compiled to a dataflow framework that executes the specifications. Declarative networking proposes the use of a declarative query language for specifying and implementing network protocols, and employs a dataflow framework at runtime for communication and maintenance of network state. The primary goal of declarative networking is to greatly simplify the process of specifying, implementing, deploying and evolving a network design. In addition, decla

  13. ¿Cómo potenciar el uso de las redes sociales como estrategia de marketing en empresas del sector hostelero? El re-descubrimiento de “Pinterest” (How to promote the use of social networks as a marketing strategy in companies in the hospitality industry

    Directory of Open Access Journals (Sweden)

    Claudia Vanesa Grandi Bustillos

    2014-12-01

    nidades que ofrecen. El objetivo del presente trabajo es analizar el empleo de las redes sociales como parte de la estrategia de marketing a tra- vés de una revisión del estado de la cuestión. Las conclusiones indican que la red social Pinterest encaja perfectamente en el sector hostelero y se recomienda su uso en aquellas empresas que deseen la exposición y publicidad de la marca, y que posean gran calidad de contenido visual.   Abstract  The traditional service marketing actions have undergone a revolution with the introduction of new technologies and especially with the widespread use of social networks. Users are influenced by the opinions that are presented on these networks when purchasing services online. The hospitality industry has also been influenced by social networks, but many hospitality companies have not detected the opportunities yet. The purpose of this paper is to analyze the use of social media as a component of the firms´ marketing strategy through a review of the state of the art. Results show that the social network Pinterest fits perfectly in the hospitality industry and its use is recommended for companies who want exposure and brand advertising with high quality visual content

  14. A Bayesian network model for predicting aquatic toxicity mode of action using two dimensional theoretical molecular descriptors

    Energy Technology Data Exchange (ETDEWEB)

    Carriger, John F. [U.S. Environmental Protection Agency, Office of Research and Development, Gulf Ecology Division, Gulf Breeze, FL, 32561 (United States); Martin, Todd M. [U.S. Environmental Protection Agency, Office of Research and Development, Sustainable Technology Division, Cincinnati, OH, 45220 (United States); Barron, Mace G., E-mail: barron.mace@epa.gov [U.S. Environmental Protection Agency, Office of Research and Development, Gulf Ecology Division, Gulf Breeze, FL, 32561 (United States)

    2016-11-15

    Highlights: • A Bayesian network was developed to classify chemical mode of action (MoA). • The network was based on the aquatic toxicity MoA for over 1000 chemicals. • A Markov blanket algorithm selected a subset of theoretical molecular descriptors. • Sensitivity analyses found influential descriptors for classifying the MoAs. • Overall precision of the Bayesian MoA classification model was 80%. - Abstract: The mode of toxic action (MoA) has been recognized as a key determinant of chemical toxicity, but development of predictive MoA classification models in aquatic toxicology has been limited. We developed a Bayesian network model to classify aquatic toxicity MoA using a recently published dataset containing over one thousand chemicals with MoA assignments for aquatic animal toxicity. Two dimensional theoretical chemical descriptors were generated for each chemical using the Toxicity Estimation Software Tool. The model was developed through augmented Markov blanket discovery from the dataset of 1098 chemicals with the MoA broad classifications as a target node. From cross validation, the overall precision for the model was 80.2%. The best precision was for the AChEI MoA (93.5%) where 257 chemicals out of 275 were correctly classified. Model precision was poorest for the reactivity MoA (48.5%) where 48 out of 99 reactive chemicals were correctly classified. Narcosis represented the largest class within the MoA dataset and had a precision and reliability of 80.0%, reflecting the global precision across all of the MoAs. False negatives for narcosis most often fell into electron transport inhibition, neurotoxicity or reactivity MoAs. False negatives for all other MoAs were most often narcosis. A probabilistic sensitivity analysis was undertaken for each MoA to examine the sensitivity to individual and multiple descriptor findings. The results show that the Markov blanket of a structurally complex dataset can simplify analysis and interpretation by

  15. Theoretical prediction of high electron mobility in multilayer MoS2 heterostructured with MoSe2.

    Science.gov (United States)

    Ji, Liping; Shi, Juan; Zhang, Z Y; Wang, Jun; Zhang, Jiachi; Tao, Chunlan; Cao, Haining

    2018-01-07

    Two-dimensional (2D) MoS2 has been considered to be one of the most promising semiconducting materials with the potential to be used in novel nanoelectronic devices. High carrier mobility in the semiconductor is necessary to guarantee a low power dissipation and a high switch speed of the corresponding electronic device. Strain engineering in 2D materials acts as an important approach to tailor and design their electronic and carrier transport properties. In this work, strain is introduced to MoS2 through perpendicularly building van der Waals heterostructures MoSe2-MoS2. Our first-principles calculations demonstrate that acoustic-phonon-limited electron mobility can be significantly enhanced in the heterostructures compared with that in pure multilayer MoS2. It is found that the effective electron mass and the deformation potential constant are relatively smaller in the heterostructures, which is responsible for the enhancement in the electron mobility. Overall, the electron mobility in the heterostructures is about 1.5 times or more of that in pure multilayer MoS2 with the same number of layers for the studied structures. These results indicate that MoSe2 is an excellent material to be heterostructured with multilayer MoS2 to improve the charge transport property.

  16. First-Principles Study of Mo Segregation in MoNi(111): Effects of Chemisorbed Atomic Oxygen.

    Science.gov (United States)

    Yu, Yanlin; Xiao, Wei; Wang, Jianwei; Wang, Ligen

    2015-12-26

    Segregation at metal alloy surfaces is an important issue because many electrochemical and catalytic properties are directly correlated to the surface composition. We have performed density functional theory calculations for Mo segregation in MoNi(111) in the presence of chemisorbed atomic oxygen. In particular, the coverage dependence and possible adsorption-induced segregation phenomena are addressed by investigating segregation energies of the Mo atom in MoNi(111). The theoretical calculated results show that the Mo atom prefers to be embedded in the bulk for the clean MoNi(111), while it segregates to the top-most layer when the oxygen coverage is thicker than 1/9 monolayer (ML). Furthermore, we analyze the densities of states for the clean and oxygen-chemisorbed MoNi(111), and see a strong covalent bonding between Mo d-band states and O p-states. The present study provides valuable insight for exploring practical applications of Ni-based alloys as hydrogen evolution electrodes.

  17. Quantum Coherence Facilitates Efficient Charge Separation at a MoS2/MoSe2 van der Waals Junction.

    Science.gov (United States)

    Long, Run; Prezhdo, Oleg V

    2016-03-09

    Two-dimensional transition metal dichalcogenides (MX2, M = Mo, W; X = S, Se) hold great potential in optoelectronics and photovoltaics. To achieve efficient light-to-electricity conversion, electron-hole pairs must dissociate into free charges. Coulomb interaction in MX2 often exceeds the charge transfer driving force, leading one to expect inefficient charge separation at a MX2 heterojunction. Experiments defy the expectation. Using time-domain density functional theory and nonadiabatic (NA) molecular dynamics, we show that quantum coherence and donor-acceptor delocalization facilitate rapid charge transfer at a MoS2/MoSe2 interface. The delocalization is larger for electron than hole, resulting in longer coherence and faster transfer. Stronger NA coupling and higher acceptor state density accelerate electron transfer further. Both electron and hole transfers are subpicosecond, which is in agreement with experiments. The transfers are promoted primarily by the out-of-plane Mo-X modes of the acceptors. Lighter S atoms, compared to Se, create larger NA coupling for electrons than holes. The relatively slow relaxation of the "hot" hole suggests long-distance bandlike transport, observed in organic photovoltaics. The electron-hole recombination is notably longer across the MoS2/MoSe2 interface than in isolated MoS2 and MoSe2, favoring long-lived charge separation. The atomistic, time-domain studies provide valuable insights into excitation dynamics in two-dimensional transition metal dichalcogenides.

  18. Sheet-like of Mo V-Sm III assembly containing [Mo V (CN) 8] 3-and ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 121; Issue 4. Sheet-like of MoV-SmIII assembly containing [MoV(CN)8]3- and Sm3+ ions as building blocks. Shu-Lin Ma Shi Ren Yue Ma Dai-Zheng Liao. Volume 121 Issue 4 July 2009 pp 421-427 ...

  19. Solvent free depolymerization of Kraft lignin to alkyl-phenolics using supported NiMo and CoMo catalysts

    NARCIS (Netherlands)

    Kumar, Chowdari Ramesh; Anand, Narani; Kloekhorst, Arjan; Cannilla, Catia; Bonura, Giuseppe; Frusteri, Francesco; Barta, Katalin; Heeres, Hero Jan

    2015-01-01

    The catalytic hydrotreatment of Kraft lignin using sulfided NiMo and CoMo catalysts on different acidic and basic supports (Al2O3, ZSM-5, activated carbon (AC) and MgO-La2O3) was studied in the absence of a solvent. Experiments were carried out in a batch set-up at a reaction temperature of 350

  20. First-Principles Study of Mo Segregation in MoNi(111: Effects of Chemisorbed Atomic Oxygen

    Directory of Open Access Journals (Sweden)

    Yanlin Yu

    2015-12-01

    Full Text Available Segregation at metal alloy surfaces is an important issue because many electrochemical and catalytic properties are directly correlated to the surface composition. We have performed density functional theory calculations for Mo segregation in MoNi(111 in the presence of chemisorbed atomic oxygen. In particular, the coverage dependence and possible adsorption-induced segregation phenomena are addressed by investigating segregation energies of the Mo atom in MoNi(111. The theoretical calculated results show that the Mo atom prefers to be embedded in the bulk for the clean MoNi(111, while it segregates to the top-most layer when the oxygen coverage is thicker than 1/9 monolayer (ML. Furthermore, we analyze the densities of states for the clean and oxygen-chemisorbed MoNi(111, and see a strong covalent bonding between Mo d-band states and O p-states. The present study provides valuable insight for exploring practical applications of Ni-based alloys as hydrogen evolution electrodes.

  1. A Bayesian network model for predicting aquatic toxicity mode of action using two dimensional theoretical molecular descriptors-abstract

    Science.gov (United States)

    The mode of toxic action (MoA) has been recognized as a key determinant of chemical toxicity but MoA classification in aquatic toxicology has been limited. We developed a Bayesian network model to classify aquatic toxicity mode of action using a recently published dataset contain...

  2. Mo-O bond doping and related-defect assisted enhancement of photoluminescence in monolayer MoS2

    Directory of Open Access Journals (Sweden)

    Xiaoxu Wei

    2014-12-01

    Full Text Available In this work, we report a strong photoluminescence (PL enhancement of monolayer MoS2 under different treatments. We find that by simple ambient annealing treatment in the range of 200 °C to 400 °C, the PL emission can be greatly enhanced by a factor up to two orders of magnitude. This enhancement can be attributed to two factors: first, the formation of Mo-O bonds during ambient exposure introduces an effective p-doping in the MoS2 layer; second, localized electrons formed around Mo-O bonds related defective sites where the electrons can be effectively localized with higher binding energy resulting in efficient radiative excitons recombination. Time resolved PL decay measurement showed that longer lifetime of the treated sample consistent with the higher quantum efficiency in PL. These results give more insights to understand the luminescence properties of the MoS2.

  3. ATP and MO25α Regulate the Conformational State of the STRADα Pseudokinase and Activation of the LKB1 Tumour Suppressor

    Science.gov (United States)

    Zeqiraj, Elton; Filippi, Beatrice Maria; Goldie, Simon; Navratilova, Iva; Boudeau, Jérôme; Deak, Maria; Alessi, Dario R.; van Aalten, Daan M. F.

    2009-01-01

    Pseudokinases lack essential residues for kinase activity, yet are emerging as important regulators of signal transduction networks. The pseudokinase STRAD activates the LKB1 tumour suppressor by forming a heterotrimeric complex with LKB1 and the scaffolding protein MO25. Here, we describe the structure of STRADα in complex with MO25α. The structure reveals an intricate web of interactions between STRADα and MO25α involving the αC-helix of STRADα, reminiscent of the mechanism by which CDK2 interacts with cyclin A. Surprisingly, STRADα binds ATP and displays a closed conformation and an ordered activation loop, typical of active protein kinases. Inactivity is accounted for by nonconservative substitution of almost all essential catalytic residues. We demonstrate that binding of ATP enhances the affinity of STRADα for MO25α, and conversely, binding of MO25α promotes interaction of STRADα with ATP. Mutagenesis studies reveal that association of STRADα with either ATP or MO25α is essential for LKB1 activation. We conclude that ATP and MO25α cooperate to maintain STRADα in an “active” closed conformation required for LKB1 activation. It has recently been demonstrated that a mutation in human STRADα that truncates a C-terminal region of the pseudokinase domain leads to the polyhydramnios, megalencephaly, symptomatic epilepsy (PMSE) syndrome. We demonstrate this mutation destabilizes STRADα and prevents association with LKB1. In summary, our findings describe one of the first structures of a genuinely inactive pseudokinase. The ability of STRADα to activate LKB1 is dependent on a closed “active” conformation, aided by ATP and MO25α binding. Thus, the function of STRADα is mediated through an active kinase conformation rather than kinase activity. It is possible that other pseudokinases exert their function through nucleotide binding and active conformations. PMID:19513107

  4. ATP and MO25alpha regulate the conformational state of the STRADalpha pseudokinase and activation of the LKB1 tumour suppressor.

    Science.gov (United States)

    Zeqiraj, Elton; Filippi, Beatrice Maria; Goldie, Simon; Navratilova, Iva; Boudeau, Jérôme; Deak, Maria; Alessi, Dario R; van Aalten, Daan M F

    2009-06-09

    Pseudokinases lack essential residues for kinase activity, yet are emerging as important regulators of signal transduction networks. The pseudokinase STRAD activates the LKB1 tumour suppressor by forming a heterotrimeric complex with LKB1 and the scaffolding protein MO25. Here, we describe the structure of STRADalpha in complex with MO25alpha. The structure reveals an intricate web of interactions between STRADalpha and MO25alpha involving the alphaC-helix of STRADalpha, reminiscent of the mechanism by which CDK2 interacts with cyclin A. Surprisingly, STRADalpha binds ATP and displays a closed conformation and an ordered activation loop, typical of active protein kinases. Inactivity is accounted for by nonconservative substitution of almost all essential catalytic residues. We demonstrate that binding of ATP enhances the affinity of STRADalpha for MO25alpha, and conversely, binding of MO25alpha promotes interaction of STRADalpha with ATP. Mutagenesis studies reveal that association of STRADalpha with either ATP or MO25alpha is essential for LKB1 activation. We conclude that ATP and MO25alpha cooperate to maintain STRADalpha in an "active" closed conformation required for LKB1 activation. It has recently been demonstrated that a mutation in human STRADalpha that truncates a C-terminal region of the pseudokinase domain leads to the polyhydramnios, megalencephaly, symptomatic epilepsy (PMSE) syndrome. We demonstrate this mutation destabilizes STRADalpha and prevents association with LKB1. In summary, our findings describe one of the first structures of a genuinely inactive pseudokinase. The ability of STRADalpha to activate LKB1 is dependent on a closed "active" conformation, aided by ATP and MO25alpha binding. Thus, the function of STRADalpha is mediated through an active kinase conformation rather than kinase activity. It is possible that other pseudokinases exert their function through nucleotide binding and active conformations.

  5. ATP and MO25alpha regulate the conformational state of the STRADalpha pseudokinase and activation of the LKB1 tumour suppressor.

    Directory of Open Access Journals (Sweden)

    Elton Zeqiraj

    2009-06-01

    Full Text Available Pseudokinases lack essential residues for kinase activity, yet are emerging as important regulators of signal transduction networks. The pseudokinase STRAD activates the LKB1 tumour suppressor by forming a heterotrimeric complex with LKB1 and the scaffolding protein MO25. Here, we describe the structure of STRADalpha in complex with MO25alpha. The structure reveals an intricate web of interactions between STRADalpha and MO25alpha involving the alphaC-helix of STRADalpha, reminiscent of the mechanism by which CDK2 interacts with cyclin A. Surprisingly, STRADalpha binds ATP and displays a closed conformation and an ordered activation loop, typical of active protein kinases. Inactivity is accounted for by nonconservative substitution of almost all essential catalytic residues. We demonstrate that binding of ATP enhances the affinity of STRADalpha for MO25alpha, and conversely, binding of MO25alpha promotes interaction of STRADalpha with ATP. Mutagenesis studies reveal that association of STRADalpha with either ATP or MO25alpha is essential for LKB1 activation. We conclude that ATP and MO25alpha cooperate to maintain STRADalpha in an "active" closed conformation required for LKB1 activation. It has recently been demonstrated that a mutation in human STRADalpha that truncates a C-terminal region of the pseudokinase domain leads to the polyhydramnios, megalencephaly, symptomatic epilepsy (PMSE syndrome. We demonstrate this mutation destabilizes STRADalpha and prevents association with LKB1. In summary, our findings describe one of the first structures of a genuinely inactive pseudokinase. The ability of STRADalpha to activate LKB1 is dependent on a closed "active" conformation, aided by ATP and MO25alpha binding. Thus, the function of STRADalpha is mediated through an active kinase conformation rather than kinase activity. It is possible that other pseudokinases exert their function through nucleotide binding and active conformations.

  6. 2D Space-Confined Synthesis of Few-Layer MoS2 Anchored on Carbon Nanosheet for Lithium-Ion Battery Anode.

    Science.gov (United States)

    Zhou, Jingwen; Qin, Jian; Zhang, Xiang; Shi, Chunsheng; Liu, Enzuo; Li, Jiajun; Zhao, Naiqin; He, Chunnian

    2015-04-28

    A facile and scalable 2D spatial confinement strategy is developed for in situ synthesizing highly crystalline MoS2 nanosheets with few layers (≤5 layers) anchored on 3D porous carbon nanosheet networks (3D FL-MoS2@PCNNs) as lithium-ion battery anode. During the synthesis, 3D self-assembly of cubic NaCl particles is adopted to not only serve as a template to direct the growth of 3D porous carbon nanosheet networks, but also create a 2D-confined space to achieve the construction of few-layer MoS2 nanosheets robustly lain on the surface of carbon nanosheet walls. In the resulting 3D architecture, the intimate contact between the surfaces of MoS2 and carbon nanosheets can effectively avoid the aggregation and restacking of MoS2 as well as remarkably enhance the structural integrity of the electrode, while the conductive matrix of 3D porous carbon nanosheet networks can ensure fast transport of both electrons and ions in the whole electrode. As a result, this unique 3D architecture manifests an outstanding long-life cycling capability at high rates, namely, a specific capacity as large as 709 mAh g(-1) is delivered at 2 A g(-1) and maintains ∼95.2% even after 520 deep charge/discharge cycles. Apart from promising lithium-ion battery anode, this 3D FL-MoS2@PCNN composite also has immense potential for applications in other areas such as supercapacitor, catalysis, and sensors.

  7. 100Mo-enriched Li2MoO4 scintillating bolometers for 0ν2β decay search: From LUMINEU to CUPID-0/Mo projects

    Science.gov (United States)

    Poda, D. V.

    2017-10-01

    A scintillating bolometer technology based on 100Mo-enriched lithium molybdate (Li2100MoO4) crystals has been developed by LUMINEU to search for neutrinoless double-beta (0ν2β) decay of 100Mo. The results of several low temperature tests at underground environments have proved the reproducibility of high detector performance and crystal radiopurity: in particular ˜5-6 keV FWHM energy resolution and at least 9σ rejection of α's in the vicinity of the 0ν2β decay of 100Mo (3034 keV) and below 10 µBq/kg bulk activity of 228Th and 226Ra. A modest acquired exposure (0.1 kg×yr) is a limiting factor of the LUMINEU experiment sensitivity to the 0ν2β decay half-life of 100Mo (T1/2 ≥ 0.7×1023 yr at 90% C.L.), however the two-neutrino 2β decay has been measured with the best up to-date accuracy, T1/2 = [6.92 ± 0.06(stat.) ± 0.36(syst.)l × 1018 yr. The applicability of the LUMINEU technology for a tonne-scale 0ν2β decay bolometric project CUPID is going to be demonstrated by the CUPID-0/Mo experiment with ˜5 kg of 100Mo embedded in forty 0.2 kg Li2100MoO4 scintillating bolometers. A first phase of the experiment with twenty Li2100MoO4 detectors is in preparation at the Modane underground laboratory (France) to start by the end of 2017. The original version of this article, supplied to AIP Publishing, contained an omission of two footnotes. In addition, the article was missing the following collaborations from the author listing: LUMINEU, EDELWEISS, and CUPID-0/Mo Collaborations. An updated version of this article was corrected and re-published on 25 October 2017.

  8. Hydrogen on hybrid MoS{sub 2}/graphene nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Maniadaki, Aristea E.; Kopidakis, Georgios [Department of Materials Science and Technology, University of Crete, Heraklion (Greece)

    2016-06-15

    Transition metal dichalcogenides are rising candidates for the replacement of Pt catalysts in water splitting. In this theoretical study we focus on the hydrogen evolution reaction part of this process and on how hydrogen (H) interacts with MoS{sub 2} nanostructures, free-standing or positioned on a graphene substrate. Density functional theory calculations confirm the stability of such nanostructures and our results for H on several configurations, from 2D infinite monolayers to quasi-1D MoS{sub 2} ribbons and quasi-0D MoS{sub 2} flakes, are presented. We calculate the adsorption energy of H atoms on various sites of the MoS{sub 2} nanostructures, notably at Mo and S active edges. Comparing free-standing and MoS{sub 2}/graphene hybrid systems we find that the effect of the support on the adsorption of H on MoS{sub 2} nanostructures is quite significant when the substrate induces strain. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Synthesis of a Mo/Nb mixed carbide

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira da Silva, V.L. [NUCAT/PEQ/COPPE/Universidade Federal do Rio de Janeiro, Caixa Postal 68502, Rio de Janeiro, RJ-21945-970 (Brazil)]|[Environmental Catalysis and Materials Laboratory, Department of Chemical Engineering, Virginia Polytechnic Institute State University, Blacksburg, Virginia 24061 (United States); Schmal, M. [NUCAT/PEQ/COPPE/Universidade Federal do Rio de Janeiro, Caixa Postal 68502, Rio de Janeiro, RJ-21945-970 (Brazil); Schwartz, V.; Oyama, S.T. [Environmental Catalysis and Materials Laboratory, Department of Chemical Engineering, Virginia Polytechnic Institute State University, Blacksburg, Virginia 24061 (United States)

    1998-07-01

    Molybdenum and niobium carbides ({beta}{endash}Mo{sub 2}C, NbC), as well as mixed carbides of molybdenum and niobium, were synthesized by the temperature-programmed carburization method (TPC) using a 20 vol.thinsp{percent} CH{sub 4}/H{sub 2} gas mixture. The starting materials were MoO{sub 3}, B-Nb{sub 2}O{sub 5}, and physical mixtures of B-Nb{sub 2}O{sub 5}/MoO{sub 3} with Nb/(Nb+Mo) atomic ratios varying from 0.2 to 0.8, respectively. Results from catalytic and temperature-programmed oxidation (TPO) measurements indicate that during the carburization of the Nb{sub 2}O{sub 5}/MoO{sub 3} physical mixture with Nb/(Nb+Mo)=0.8 there is, besides {beta}{endash}Mo{sub 2}C and NbC formation, the appearance of a carbidic phase not detectable by x-ray diffraction (XRD). This phase appears to be highly active and selective for the dibenzothiophene hydrodesulfurization (HDS) reaction. {copyright} {ital 1998 Materials Research Society.}

  10. Development of production of {sup 99}Mo from LEU target

    Energy Technology Data Exchange (ETDEWEB)

    Adang, H.G.; Mutalib, A.; Lubis, H. [Radioisotope Production Centre, National Atomic Energy Agency, Kawasan Puspiptek, Serpong (Indonesia)] [and others

    1998-10-01

    {sup 99}TC, the most popular radioisotope in nuclear medicine, is daughter of {sup 99}Mo. {sup 99}Mo is produced in research reactor by irradiating of high enriched uranium (HEU). However, in recent year, strict regulation that has been implemented by USA DOE and NPT has led to the difficulty in getting HEU. Therefore, BATAN has tried to develop the production of {sup 99}Mo by using low enriched uranium (LEU). The research involves the use of LEU in the production of {sup 99}Mo. This research was started in 1994 by joint-research between BATAN and Argonne National Laboratory USA. This program is divided into three research groups. The first group emphasizes its research on fabrication of LEU foil that is going to be irradiated. The second group studies the irradiation`s aspects and physical characteristic of irradiated LEU foils. The third group studies the radiochemical separation process of fission product {sup 99}Mo from solution of irradiated LEU foils. There are five steps that are carried out in studying of radiochemical separation of {sup 99}Mo from irradiated LEU. First is designing a dissolver that is going to be used in dissolving of LEU foil and testing its reliability. Second is dissolving LEU in the new design dissolver. Third is evaluation the modified of Cintichem`s radiochemical separation process of {sup 99}Mo from LEU. Forth is modifying the Cintichem`s radiochemical separation process of {sup 99}Mo from the solution of irradiated LEU. And fifth is using the modified of Cintichem`s radiochemical separation process for separation {sup 99}Mo from solution of irradiated LEU. The first through the forth steps of experiments were already carried out and will be reported in this workshop, whereas the fifth step of experiment is going to be conducted in February 1998. (author)

  11. Stress reduction of Mo/Si multilayer structures

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, S.S.; Salashchenko, N.N. E-mail: salashch@ipn.sci-nnov.ru; Suslov, L.A.; Yablonsky, A.N.; Zuev, S.Y

    2001-09-01

    Due to the stringent surface figure requirements for the multilayer-coated optics in an extreme ultraviolet (EUV) projection lithography system make it desirable to minimize deformation due to the multilayer structure stress. However, the stress must be reduced or compensated without reducing the EUV reflectivity, since the reflectivity has a strong impact on the throughput of the EUV lithography tool. In this work, we evaluate techniques for stress reduction and compensation as applied to multilayer Mo/Si structures. The experimental research of multilayer Mo/Si-structures by the methods of X-ray reflectometry and electron microscopy has shown that reflectivity of Mo/Si-structures largely depends on the parameter {gamma}=d{sub Mo}/d and in the spectral region of 13-13.7 nm reaches the maximum value at {gamma}{approx}0.42-0.44. The measured film stress for Mo/Si films with EUV reflectances near 66-69% at 13.3 nm is approximately -250 MPa (compressive). Variation of the Mo-to-Si ratio can be used to reduce the stress to near-zero levels but at a large loss in EUV reflectance ({approx}54-57%). Technologically it is easiest to use for a buffer layer a multilayer structure made of the same materials (Mo and Si) as the top, reflecting, structure, but with a different parameter {gamma}{approx}0.8. The stress in the structures containing antistress buffer sublayers was {sigma}=-6 MPa. The reflectivity values for these structures are quite close, and still the reflection coefficient of the Mo/Si structure deposited on a substrate with an antistress Mo/Si buffer coating was smaller by 0.5-0.7% in absolute values smaller.

  12. Comparing English and Mo/Deg Nominal Group Qualifiers

    Directory of Open Access Journals (Sweden)

    Anto Sylvester Kwabena

    2014-03-01

    Full Text Available The task of this study is primarily to investigate the differences between English and Mo/Deg nominal group (NG qualifiers to identify any similarities within the NG qualification structures of these languages. In otherwise, the study finds answers to the questions:  “What are the qualifying elements within the Mo/Deg and English NGs?” and “What are the differences and similarities between the Mo/Deg NG qualification and that of English?” Using homogeneous sampling, the study purposefully sampled thirty (30 educated Mos/Dega (speakers of the Mo/Deg language. Short simple English sentences containing NG qualifiers designed by the researcher were given to them to translate into Mo/Deg. This was to see how the qualifiers are used in the language. Also, some of these sentences were given to some members of the staff of the Mo/Deg project of GILLBT to translate into Mo/Deg for further correct use of the qualifiers in the Mo/Deg language. The translated versions were then collected as data and analysed based on the Systemic Grammar principles of the NG structure. The results showed that the adjectival groups (AdjG, the clause, the numerals, and the determiners (pre-central, central, and post-central occur at the qualifier position in Mo/Deg, whereas in English, it is the prepositional groups (PG, the adjectival groups (AdjG (under some conditions, and the clause, which occupy the qualifier slot. However, it was also found out that the common linguistic units which occur in both languages as qualifiers are the adjectival groups and the clause.

  13. Syntactic Survey of Determiners in Mo/Deg Language

    Directory of Open Access Journals (Sweden)

    Anto Sylvester Kwabena

    2014-08-01

    Full Text Available This study is descriptive, and it is set out to primarily investigate the use and order of determiners in the Mo/Deg language. The study finds answers to the questions, “What determiner types are there in the Mo/Deg language, and in what order do they collocate with the head of the noun phrase?” Using purposive sampling, the study gathered data from forty (40 literate native speakers of the Mo/Deg language who were also very proficient in English. Short simple English sentences containing noun phrases with pre-determiners of all kind, central determiners of all types, and post-determiners of all kind were designed and given to the respondents to rewrite in Mo/Deg. This was to observe the order of determiners in the language. Also, some of these sentences were given to some staff of the Mo/Deg project of the Ghana Institute of Linguistics, Literacy and Bible Translation (GILLBT to translate into Mo/Deg since they are deemed to have deeper knowledge of the language. This was to ensure further correctness of the use and order of determiners in the language. The translations comprised the data which was analysed using the Systemic Grammar principles of the NG structure. The results showed that the Mo/Deg language has pre-determiner items and that these pre-determiners are not followed by any other words like adjectives. It further showed that it is permissible for some members of the same pre-determiner class to co-occur. The study further found out that the Mo/Deg language has three types of post-head determiners: the post-head post-determiners, the post-head central determiners, and the post-head pre-determiners. It therefore concluded that the Mo/Deg language has a very complex determiner structure.

  14. Production optimization of {sup 99}Mo/{sup 99m}Tc zirconium molybate gel generators at semi-automatic device: DISIGEG

    Energy Technology Data Exchange (ETDEWEB)

    Monroy-Guzman, F., E-mail: fabiola.monroy@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, 52750, Estado de Mexico (Mexico); Rivero Gutierrez, T., E-mail: tonatiuh.rivero@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, 52750, Estado de Mexico (Mexico); Lopez Malpica, I.Z.; Hernandez Cortes, S.; Rojas Nava, P.; Vazquez Maldonado, J.C. [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca S/N, La Marquesa, Ocoyoacac, 52750, Estado de Mexico (Mexico); Vazquez, A. [Instituto Mexicano del Petroleo, Eje Central Norte Lazaro Cardenas 152, Col. San Bartolo Atepehuacan, 07730, Mexico D.F. (Mexico)

    2012-01-15

    DISIGEG is a synthesis installation of zirconium {sup 99}Mo-molybdate gels for {sup 99}Mo/{sup 99m}Tc generator production, which has been designed, built and installed at the ININ. The device consists of a synthesis reactor and five systems controlled via keyboard: (1) raw material access, (2) chemical air stirring, (3) gel dried by air and infrared heating, (4) moisture removal and (5) gel extraction. DISIGEG operation is described and dried condition effects of zirconium {sup 99}Mo- molybdate gels on {sup 99}Mo/{sup 99m}Tc generator performance were evaluated as well as some physical-chemical properties of these gels. The results reveal that temperature, time and air flow applied during the drying process directly affects zirconium {sup 99}Mo-molybdate gel generator performance. All gels prepared have a similar chemical structure probably constituted by three-dimensional network, based on zirconium pentagonal bipyramids and molybdenum octahedral. Basic structural variations cause a change in gel porosity and permeability, favouring or inhibiting {sup 99m}TcO{sub 4}{sup -} diffusion into the matrix. The {sup 99m}TcO{sub 4}{sup -} eluates produced by {sup 99}Mo/{sup 99m}Tc zirconium {sup 99}Mo-molybdate gel generators prepared in DISIGEG, air dried at 80 Degree-Sign C for 5 h and using an air flow of 90 mm, satisfied all the Pharmacopoeias regulations: {sup 99m}Tc yield between 70-75%, {sup 99}Mo breakthrough less than 3 Multiplication-Sign 10{sup -3}%, radiochemical purities about 97% sterile and pyrogen-free eluates with a pH of 6. - Highlights: Black-Right-Pointing-Pointer {sup 99}Mo/{sup 99m}Tc generators based on {sup 99}Mo-molybdate gels were synthesized at a semi-automatic device. Black-Right-Pointing-Pointer Generator performances depend on synthesis conditions of the zirconium {sup 99}Mo-molybdate gel. Black-Right-Pointing-Pointer {sup 99m}TcO{sub 4}{sup -} diffusion and yield into generator depends on gel porosity and permeability. Black

  15. Detecting the Extent of Eutectoid Transformation in U-10Mo

    Energy Technology Data Exchange (ETDEWEB)

    Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jana, Saumyadeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McInnis, Colleen A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lombardo, Nicholas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sweet, Lucas E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Manandhar, Sandeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-08-31

    During eutectoid transformation of U-10Mo alloy, uniform metastable γ UMo phase is expected to transform to a mixture of α-U and γ’-U2Mo phase. The presence of transformation products in final U-10Mo fuel, especially the α phase is considered detrimental for fuel irradiation performance, so it is critical to accurately evaluate the extent of transformation in the final U-10Mo alloy. This phase transformation can cause a volume change that induces a density change in final alloy. To understand this density and volume change, we developed a theoretical model to calculate the volume expansion and resultant density change of U-10Mo alloy as a function of the extent of eutectoid transformation. Based on the theoretically calculated density change for 0 to 100% transformation, we conclude that an experimental density measurement system will be challenging to employ to reliably detect and quantify the extent of transformation. Subsequently, to assess the ability of various methods to detect the transformation in U-10Mo, we annealed U-10Mo alloy samples at 500°C for various times to achieve in low, medium, and high extent of transformation. After the heat treatment at 500°C, the samples were metallographically polished and subjected to optical microscopy and x-ray diffraction (XRD) methods. Based on our assessment, optical microscopy and image processing can be used to determine the transformed area fraction, which can then be correlated with the α phase volume fraction measured by XRD analysis. XRD analysis of U-10Mo aged at 500°C detected only α phase and no γ’ was detected. To further validate the XRD results, atom probe tomography (APT) was used to understand the composition of transformed regions in U-10Mo alloys aged at 500°C for 10 hours. Based on the APT results, the lamellar transformation product was found to comprise α phase with close to 0 at% Mo and γ phase with 28–32 at% Mo, and the Mo concentration was highest at the

  16. Processing and charge state engineering of MoOx

    Directory of Open Access Journals (Sweden)

    Aitana Tarazaga Martín-Luengo

    2017-01-01

    Full Text Available The effects of wet chemical processing employed in device fabrication standards are studied on molybdenum oxide (MoOx ultra-thin films. We have combined x-ray photoelectron spectroscopy (XPS, angle resolved XPS and x-ray reflectivity to gain insight into the changes in composition, structure and electronic states upon treatment of films with different initial stoichiometry prepared by reactive sputtering. Our results show significant reduction effects associated with the development of gap states in MoOx, as well as changes in the composition and structure of the films, systematically correlated with the initial oxidation state of Mo.

  17. Technical Design Report of the MoEDAL Experiment

    CERN Document Server

    Pinfold, James; Yao, Y; Cecchini, S; Giacomelli, G; Giorgini, M; Patrizii, L; Sirri, G; Lacarrère, D H; Kinoshita, K; Jakubek, J; Platkevic, M; Pospísil, S; Vykydal, Z; Hott, T; Houdayer, A; Leroy, Claude; Swain, J; Felea, D; Hasegan, D; Pavalas, G E; Popa, V; CERN. Geneva. The LHC experiments Committee; LHCC

    2009-01-01

    The principal aim of the MoEDAL (Monopole and Exotics Detector at the LHC) project is to directly search for the Magnetic Monopole and other highly ionizing Stable (or pseudo-stable) Massive Particles (SMPs) at the LHC. The MoEDAL detector is comprised of an array of plastic Nuclear Track Detectors deployed in the LHCb-VELO cavern at point 8, on the LHC ring. This Technical Design Report details the motivation and physics reach of the experiment, the design of the MoEDAL detector and the operating parameters of the experiment.

  18. The network researchers' network

    DEFF Research Database (Denmark)

    Henneberg, Stephan C.; Jiang, Zhizhong; Naudé, Peter

    2009-01-01

    The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987). In thi......The Industrial Marketing and Purchasing (IMP) Group is a network of academic researchers working in the area of business-to-business marketing. The group meets every year to discuss and exchange ideas, with a conference having been held every year since 1984 (there was no meeting in 1987......). In this paper, based upon the papers presented at the 22 conferences held to date, we undertake a Social Network Analysis in order to examine the degree of co-publishing that has taken place between this group of researchers. We identify the different components in this database, and examine the large main...

  19. Mo-C Multilayered CVD Coatings

    Directory of Open Access Journals (Sweden)

    A. Sagalovych

    2013-12-01

    Full Text Available Production processes of multi-layered Mo-C coatings by the method of chemical vapor deposition (CVD with the use of organometallic compounds were developed. Coatings are applied on technical purpose steel DIN 1.2379 (H12F1 and DIN 1.7709 (25H2MF (ÉI10 heat-treated ball with the high class of surface roughness (> 10. The average deposition rate was 50 μm / h. The optimal conditions of deposition coatings for different technological schemas were defined. Metallographic investigations of the obtained coatings were carried out. Tribological studies of the friction and wear characteristics of sliding friction in conditions of boundary lubrication of Ï-S multilayered CVD coatings shows, that coatings have low friction coefficients (0075-0095 at loads up to 2.0 kN, showed high resistance to wear and are effective in increasing the stability of the pair for precision friction pairs of hydraulical units.

  20. Magnetotransport properties of MoP2

    Science.gov (United States)

    Wang, Aifeng; Graf, D.; Stein, Aaron; Liu, Yu; Yin, Weiguo; Petrovic, C.

    2017-11-01

    We report magnetotransport and de Haas-van Alphen (dHvA) effect studies on MoP2 single crystals, predicted to be a type-II Weyl semimetal with four pairs of robust Weyl points located below the Fermi level and long Fermi arcs. The temperature dependence of resistivity shows a peak before saturation, which does not move with magnetic field. Large nonsaturating magnetoresistance (MR) was observed, and the field dependence of MR exhibits a crossover from semiclassical weak-field B2 dependence to the high-field linear-field dependence, indicating the presence of Dirac linear energy dispersion. In addition, a systematic violation of Kohler's rule was observed, consistent with multiband electronic transport. Strong spin-orbit coupling splitting has an effect on dHvA measurements whereas the angular-dependent dHvA orbit frequencies agree well with the calculated Fermi surface. The cyclotron effective mass ˜1.6 me indicates the bands might be trivial, possibly since the Weyl points are located below the Fermi level.

  1. Three-Dimensional Heterostructures of MoS 2 Nanosheets on Conducting MoO 2 as an Efficient Electrocatalyst To Enhance Hydrogen Evolution Reaction

    KAUST Repository

    Nikam, Revannath Dnyandeo

    2015-10-05

    Molybdenum disulfide (MoS) is a promising catalyst for hydrogen evolution reaction (HER) because of its unique nature to supply active sites in the reaction. However, the low density of active sites and their poor electrical conductivity have limited the performance of MoS in HER. In this work, we synthesized MoS nanosheets on three-dimensional (3D) conductive MoO via a two-step chemical vapor deposition (CVD) reaction. The 3D MoO structure can create structural disorders in MoS nanosheets (referred to as 3D MoS/MoO), which are responsible for providing the superior HER activity by exposing tremendous active sites of terminal disulfur of S2 (in MoS) as well as the backbone conductive oxide layer (of MoO) to facilitate an interfacial charge transport for the proton reduction. In addition, the MoS nanosheets could protect the inner MoO core from the acidic electrolyte in the HER. The high activity of the as-synthesized 3D MoS/MoO hybrid material in HER is attributed to the small onset overpotential of 142 mV, a largest cathodic current density of 85 mA cm, a low Tafel slope of 35.6 mV dec, and robust electrochemical durability.

  2. Study of the dynamics of the MoO2-Mo2C system for catalytic partial oxidation reactions

    Science.gov (United States)

    Cuba Torres, Christian Martin

    On a global scale, the energy demand is largely supplied by the combustion of non-renewable fossil fuels. However, their rapid depletion coupled with environmental and sustainability concerns are the main drivers to seek for alternative energetic strategies. To this end, the sustainable generation of hydrogen from renewable resources such as biodiesel would represent an attractive alternative solution to fossil fuels. Furthermore, hydrogen's lower environmental impact and greater independence from foreign control make it a strong contender for solving this global problem. Among a wide variety of methods for hydrogen production, the catalytic partial oxidation offers numerous advantages for compact and mobile fuel processing systems. For this reaction, the present work explores the versatility of the Mo--O--C catalytic system under different synthesis methods and reforming conditions using methyl oleate as a surrogate biodiesel. MoO2 exhibits good catalytic activity and exhibits high coke-resistance even under reforming conditions where long-chain oxygenated compounds are prone to form coke. Moreover, the lattice oxygen present in MoO2 promotes the Mars-Van Krevelen mechanism. Also, it is introduced a novel beta-Mo2C synthesis by the in-situ formation method that does not utilize external H2 inputs. Herein, the MoO 2/Mo2C system maintains high catalytic activity for partial oxidation while the lattice oxygen serves as a carbon buffer for preventing coke formation. This unique feature allows for longer operation reforming times despite slightly lower catalytic activity compared to the catalysts prepared by the traditional temperature-programmed reaction method. Moreover, it is demonstrated by a pulse reaction technique that during the phase transformation of MoO2 to beta-Mo2C, the formation of Mo metal as an intermediate is not responsible for the sintering of the material wrongly assumed by the temperature-programmed method.

  3. Ternary CoS2/MoS2/RGO electrocatalyst with CoMoS phase for efficient hydrogen evolution

    Science.gov (United States)

    Liu, Yan-Ru; Shang, Xiao; Gao, Wen-Kun; Dong, Bin; Chi, Jing-Qi; Li, Xiao; Yan, Kai-Li; Chai, Yong-Ming; Liu, Yun-Qi; Liu, Chen-Guang

    2017-08-01

    CoMoS phase with metallic character plays crucial role on enhancing the activity of MoS2 electrocatalysts for hydrogen evolution reaction (HER). However, only Co atoms located in the edges of MoS2 can create CoMoS phase, so it is a challenge to obtain CoMoS phase with homogeneous distribution limited by the layered MoS2 and doping method of Co. Herein, we reported a simple one-pot hydrothermal method to prepare novel ternary CoS2/MoS2/RGO with CoMoS phase for HER using reduced graphene oxide (RGO) as support. XPS proves the formation of CoMoS phase, implying the enhanced activity for HER. RGO support ensures the well distribution of CoMoS phase and enhances the conductivity of CoS2/MoS2/RGO. Compared to CoS2/RGO, MoS2/RGO and CoS2/MoS2, the obtained CoS2/MoS2/RGO shows superior activity for HER with an onset overpotential of -80 mV (vs. RHE), small Tafel slope of 56 mV dec-1, high exchange current density of 11.4 μA cm-2 and rigid electrochemical durability. The enhanced performances for HER may be ascribed to the formation of CoMoS phase with high activity and the existence of RGO support with good electrical conductivitys in ternary CoS2/MoS2/RGO. Therefore, the introduction of CoMoS phase and RGO into MoS2 could effectively enhance electrocatalytic properties for HER.

  4. Network cosmology.

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology.

  5. Network Cosmology

    Science.gov (United States)

    Krioukov, Dmitri; Kitsak, Maksim; Sinkovits, Robert S.; Rideout, David; Meyer, David; Boguñá, Marián

    2012-01-01

    Prediction and control of the dynamics of complex networks is a central problem in network science. Structural and dynamical similarities of different real networks suggest that some universal laws might accurately describe the dynamics of these networks, albeit the nature and common origin of such laws remain elusive. Here we show that the causal network representing the large-scale structure of spacetime in our accelerating universe is a power-law graph with strong clustering, similar to many complex networks such as the Internet, social, or biological networks. We prove that this structural similarity is a consequence of the asymptotic equivalence between the large-scale growth dynamics of complex networks and causal networks. This equivalence suggests that unexpectedly similar laws govern the dynamics of complex networks and spacetime in the universe, with implications to network science and cosmology. PMID:23162688

  6. Ferromagnetism in freestanding MoS2 nanosheets

    Science.gov (United States)

    2013-01-01

    Freestanding MoS2 nanosheets with different sizes were prepared through a simple exfoliated method by tuning the ultrasonic time in the organic solvent. Magnetic measurement results reveal the clear room-temperature ferromagnetism for all the MoS2 nanosheets, in contrast to the pristine MoS2 in its bulk form which shows diamagnetism only. Furthermore, results indicate that the saturation magnetizations of the nanosheets increase as the size decreases. Combining the X-ray photoelectron spectroscopy, transmission electron microscopy, and electron spin resonance results, it is suggested that the observed magnetization is related to the presence of edge spins on the edges of the nanosheets. These MoS2 nanosheets may find applications in nanodevices and spintronics by controlling the edge structures. PMID:23496904

  7. Effect of Silicon in U-10Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Kautz, Elizabeth J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Devaraj, Arun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kovarik, Libor [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lavender, Curt A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Joshi, Vineet V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-08-31

    This document details a method for evaluating the effect of silicon impurity content on U-10Mo alloys. Silicon concentration in U-10Mo alloys has been shown to impact the following: volume fraction of precipitate phases, effective density of the final alloy, and 235-U enrichment in the gamma-UMo matrix. This report presents a model for calculating these quantities as a function of Silicon concentration, which along with fuel foil characterization data, will serve as a reference for quality control of the U-10Mo final alloy Si content. Additionally, detailed characterization using scanning electron microscope imaging, transmission electron microscope diffraction, and atom probe tomography showed that Silicon impurities present in U-10Mo alloys form a Si-rich precipitate phase.

  8. 9 Cr-- 1 Mo steel material for high temperature application

    Science.gov (United States)

    Jablonski, Paul D; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

    2012-11-27

    One or more embodiments relates to a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The 9 Cr-1 Mo steel has a tempered martensite microstructure and is comprised of both large (0.5-3 .mu.m) primary titanium carbides and small (5-50 nm) secondary titanium carbides in a ratio of. from about 1:1.5 to about 1.5:1. The 9 Cr-1 Mo steel may be fabricated using exemplary austenizing, rapid cooling, and tempering steps without subsequent hot working requirements. The 9 Cr-1 Mo steel exhibits improvements in total mass gain, yield strength, and time-to-rupture over ASTM P91 and ASTM P92 at the temperature and time conditions examined.

  9. Monolayer MoS2 heterojunction solar cells

    KAUST Repository

    Tsai, Menglin

    2014-08-26

    We realized photovoltaic operation in large-scale MoS2 monolayers by the formation of a type-II heterojunction with p-Si. The MoS 2 monolayer introduces a built-in electric field near the interface between MoS2 and p-Si to help photogenerated carrier separation. Such a heterojunction photovoltaic device achieves a power conversion efficiency of 5.23%, which is the highest efficiency among all monolayer transition-metal dichalcogenide-based solar cells. The demonstrated results of monolayer MoS 2/Si-based solar cells hold the promise for integration of 2D materials with commercially available Si-based electronics in highly efficient devices. © 2014 American Chemical Society.

  10. Pressure confinement effect in MoS2 monolayers

    Science.gov (United States)

    Li, Fangfei; Yan, Yalan; Han, Bo; Li, Liang; Huang, Xiaoli; Yao, Mingguang; Gong, Yuanbo; Jin, Xilian; Liu, Baoli; Zhu, Chuanrui; Zhou, Qiang; Cui, Tian

    2015-05-01

    With ever increasing interest in layered materials, molybdenum disulfide has been widely investigated due to its unique optoelectronic properties. Pressure is an effective technique to tune the lattice and electronic structure of materials such that high pressure studies can disclose new structural and optical phenomena. In this study, taking MoS2 as an example, we investigate the pressure confinement effect on monolayer MoS2 by in situ high pressure Raman and photoluminescence (PL) measurements. Our results reveal a structural deformation of monolayer MoS2 starting from 0.84 GPa, which is evidenced by the splitting of E12g and A1g modes. A further compression leads to a transition from the 1H-MoS2 phase to a novel structure evidenced by the appearance of two new peaks located at 200 and 240 cm-1. This is a distinct feature of monolayer MoS2 compared with bulk MoS2. The new structure is supposed to have a distorted unit with the S atoms slided within a single layer like that of metastable 1T'-MoS2. However, unlike the non-photoluminescent 1T'-MoS2 structure, our monolayer shows a remarkable PL peak and a pressure-induced blue shift up to 13.1 GPa. This pressure-dependent behavior might enable the development of novel devices with multiple phenomena involving the strong coupling of the mechanical, electrical and optical properties of layered nanomaterials.With ever increasing interest in layered materials, molybdenum disulfide has been widely investigated due to its unique optoelectronic properties. Pressure is an effective technique to tune the lattice and electronic structure of materials such that high pressure studies can disclose new structural and optical phenomena. In this study, taking MoS2 as an example, we investigate the pressure confinement effect on monolayer MoS2 by in situ high pressure Raman and photoluminescence (PL) measurements. Our results reveal a structural deformation of monolayer MoS2 starting from 0.84 GPa, which is evidenced by the

  11. Effect of Mo Dispersion Size and Water Vapor on Oxidation of Two-Phase Directionally Solidified NiAl-9Mo In-Situ Composites

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Michael P [ORNL; Bei, Hongbin [ORNL; Meisner, Roberta Ann [ORNL; Lance, Michael J [ORNL; Tortorelli, Peter F [ORNL

    2014-01-01

    Oxidation of two-phase NiAl-9Mo eutectics with 3 different growth rates/2nd phase Mo dispersion sizes were investigated at 900 C in air and air with 10% water vapor. Good oxidation resistance via alumina formation was observed in dry air, with Mo volatilization loss minimized by fine submicron Mo dispersions. However, extensive Mo volatilization and in-place internal oxidation of prior Mo phase regions was observed in wet air oxidation. Ramifications of this phenomenon for the development of multi-phase high-temperature alloys are discussed

  12. Ternary CoS{sub 2}/MoS{sub 2}/RGO electrocatalyst with CoMoS phase for efficient hydrogen evolution

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yan-Ru; Shang, Xiao [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Gao, Wen-Kun [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580 (China); Dong, Bin, E-mail: dongbin@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); College of Science, China University of Petroleum (East China), Qingdao 266580 (China); Chi, Jing-Qi; Li, Xiao; Yan, Kai-Li; Chai, Yong-Ming [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Yun-Qi, E-mail: liuyq@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China); Liu, Chen-Guang [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580 (China)

    2017-08-01

    Highlights: • Ternary CoS{sub 2}/MoS{sub 2}/RGO with CoMoS phase as electrocatalyst for HER was prepared. • CoMoS phase have the metallic nature and highly intrinsic activity for HER. • RGO support ensures good distribution of CoMoS phase and enhances the conductivity. • The introduction of CoMoS and RGO may be a novel strategy for efficient HER of MoS{sub 2}. - Abstract: CoMoS phase with metallic character plays crucial role on enhancing the activity of MoS{sub 2} electrocatalysts for hydrogen evolution reaction (HER). However, only Co atoms located in the edges of MoS{sub 2} can create CoMoS phase, so it is a challenge to obtain CoMoS phase with homogeneous distribution limited by the layered MoS{sub 2} and doping method of Co. Herein, we reported a simple one-pot hydrothermal method to prepare novel ternary CoS{sub 2}/MoS{sub 2}/RGO with CoMoS phase for HER using reduced graphene oxide (RGO) as support. XPS proves the formation of CoMoS phase, implying the enhanced activity for HER. RGO support ensures the well distribution of CoMoS phase and enhances the conductivity of CoS{sub 2}/MoS{sub 2}/RGO. Compared to CoS{sub 2}/RGO, MoS{sub 2}/RGO and CoS{sub 2}/MoS{sub 2}, the obtained CoS{sub 2}/MoS{sub 2}/RGO shows superior activity for HER with an onset overpotential of −80 mV (vs. RHE), small Tafel slope of 56 mV dec{sup −1}, high exchange current density of 11.4 μA cm{sup −2} and rigid electrochemical durability. The enhanced performances for HER may be ascribed to the formation of CoMoS phase with high activity and the existence of RGO support with good electrical conductivitys in ternary CoS{sub 2}/MoS{sub 2}/RGO. Therefore, the introduction of CoMoS phase and RGO into MoS{sub 2} could effectively enhance electrocatalytic properties for HER.

  13. Toroidal deuteron accelerator for Mo-98 neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Wagner L., E-mail: wagner.leite@ifnmg.edu.br, E-mail: tprcampos@pq.cnpq.br [Instituto Federal do Norte de Minas Gerais (IFN-MG), Montes Claros, MG (Brazil); Campos, Tarcisio P.R. Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    The radionuclide Tc-{sup 99m} is the most useful radioisotope in nuclear medicine. It can be produced by the Mo-99 beta minus decay. Mo-99 has often been produced in a high- flux nuclear reactor through radioactive neutron capture reactions on Mo-98. The present paper provides a preliminary design of a toroidal transmutation system (TTS) based on a toroidal compact deuteron accelerator, which can provide the Mo-98 transmutation into Mo-99. This system is essentially composed of a multi-aperture plasma electrode and a target, submitted to 180 kV, where a positive deuteron beam is accelerated toward a titanium-target loaded with deuterium in which nuclear d-d fusion reactions are induced. The Particle Studio package of the Computer Simulation Technology (CST) software was applied to design, simulate and optimize the deuteron beam on the target. MCNP code provided to neutronic analysis. Based on electromagnetic and neutronic simulations, the neutron yield and reaction rates were estimated. The simulated data allowed appraising the Mo-99 activity. A TTS, in a specific configuration, could produce a total deuterium current of 1.6 A at the target and a neutron yield of 10{sup 13} n.s{sup -1}. In a arrangement of 30 column samples, TTS provides 230 mCi s{sup -1} Mo{sup 99} in each column, which represents 80% of Tc-99m in secular equilibrium. As conclusion, the system holds potential for generating Mo-99 and Tc-99m in a suitable activity in secular equilibrium. (author)

  14. Microstructures in rapidly solidified Ni-Mo alloys

    Science.gov (United States)

    Jayaraman, N.; Tewari, S. N.; Hemker, K. J.; Glasgow, T. K.

    1986-01-01

    Ni-Mo alloys of compositions ranging from pure Ni to Ni-40 at. percent Mo were rapidly solidified by Chill Block Melt Spinning in vacuum and were examined by optical metallography, X-ray diffraction and transmission electron microscopy. Rapid solidification resulted in an extension of molybdenum solubility in nickel from 28 to 37.5 at. percent. A number of different phases and microstructures were seen at different depths (solidification conditions) from the quenched surface of the melt spun ribbons.

  15. Real-Time Seismic Monitoring of Thenewcape Girardeau (mo) Bridge and Recorded Earthquake Response

    Science.gov (United States)

    çelebi, Mehmet

    This paper introduces the state of the art, real-time and broad-band seismic monitoring network implemented for the 1206 m [3956 ft] long, cable-stayed Bill Emerson Memorial Bridge in Cape Girardeau (MO), a new Mississippi River crossing, approximately 80 km from the epicentral region of the 1811-1812 New Madrid earthquakes. Design of the bridge accounted for the possibility of a strong earthquake (magnitude 7.5 or greater) during the design life of the bridge. The monitoring network consists of a superstructure and two free-field arrays and comprises a total of 84 channels of accelerometers deployed on the superstructure, pier foundations and free-field in the vicinity of the bridge. The paper also introduces the high quality response data obtained from the network. Such data is aimed to be used by the owner, researchers and engineers to (1) assess the performance of the bridge, (2) check design parameters, including the comparison of dynamic characteristics with actual response, and (3) better design future similar bridges. Preliminary analyses of low-amplitude ambient vibration data and that from a small earthquake reveal specific response characteristics of this new bridge and the free-field in its proximity. There is coherent tower-cabledeck interaction that sometimes results in amplified ambient motions. Also, while the motions at the lowest (tri-axial) downhole accelerometers on both MO and IL sides are practically free-from any feedback from the bridge, the motions at the middle downhole and surface accelerometers are significantly influenced by amplified ambient motions of the bridge.

  16. Characterization of Thin Walled Mo Tubing produced by FBCVD

    Energy Technology Data Exchange (ETDEWEB)

    Beaux, Miles Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-01-21

    The goal of this report is to delineate the results of material characterization performed on Mo tubing produced via the fluidized bed chemical vapor deposition (FBCVD) method. Scanning electron microscopy (SEM) imaging reveals that small randomly oriented grains are achieved in the Mo deposition, but do not persist throughout the entire thickness of the material. Energy dispersive spectroscopy (EDS) reveals the Mo tubes contain residual chlorine and oxygen. EDS measurements on the tube surfaces separated from glass and quartz substrates reveal substrate material adhered to this surface. X-ray diffraction (XRD) revealed the presence of carbon contaminant in the form of Mo2C and oxygen in the form of MoO2. Combustion infrared detection (CID) and inert gas fusion (IGF) performed at Luvak Inc. was used to quantify weight percentages of oxygen and carbon in the tubes produced. Hardness value of the FBCVD Mo was found to be comparable to low carbon arc cast molybdenum.

  17. MoEDAL: Passive but no less active

    CERN Multimedia

    MoEDAL Collaboration

    2015-01-01

    Relying almost completely on passive detectors, MoEDAL is a pioneering experiment designed to search for highly ionising avatars of new physics, such as magnetic monopoles or massive (pseudo-)stable charged particles. The first test detectors were deployed at LHC Point 8 in 2012 and analysed in 2013, and the full MoEDAL detector was installed in the winter of 2014 to start data-taking during Run 2 this year.   The image shows the MoEDAL detector systems installed at Point 8 of the LHC. MoEDAL’s groundbreaking physics programme defines over 30 scenarios that yield potentially revolutionary insights into such fundamental questions as: are there extra dimensions or new symmetries? Does magnetic charge exist? What is the nature of dark matter? And how did the big bang develop? MoEDAL's purpose is to meet such far-reaching challenges at the frontier of the field. Having reached its final configuration in winter 2014, MoEDAL now consists of ten layers of plastic attached to the ...

  18. Effects of Cr, Mo, W, Mn and Ni on toughness of 2. 25Cr-Mo-V rotor steel. 2. 25Cr-Mo-V tanko no jinsei ni oyobosu Cr, Mo, W, Mn oyobi Ni no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kadoya, Y. (Mitsubishi Heavy Industries Ltd., Tokyo (Japan). Takasago Research and Development Center); Kitai, T.; Tsuji, I.; Matsuo, A. (Mitsubishi Heavy Industries Ltd., Tokyo (Japan)); Tanaka, Y.; Azuma, T. (The Japan Steel Works Ltd., Tokyo (Japan). Muroran Research Lab.); Ikeda, Y. (The Japan Steel Works Ltd., Tokyo (Japan))

    1993-08-01

    2.25Cr-Mo-V rotor steel is developed and put into practical use as a high and low pressure suitable rotor steel and the gas turbine disk materials. In this study, as a basic component of 2.25Cr-Mo-V steel, 12 kinds of alloys with the additions of Cr, Mo, W, Mn and Ni were made, the impact experiments were carried out, effect of the alloying elements on toughness was examined, and effect of the alloying elements on the precipitation of carbide was investigated. Main results obtained were as follows: Cr, Mo, Mn and Ni additions decreased the Bainite start temperature (Bs) of 2.25Cr-Mo-V steel, Cr and Ni additions decreased Fracture Appearance Transition Temperature (FATT), and Mn addition did not give a significant change on the FATT. Mo addition decreased the FATT, when this addition is more than 1.5%, the FATT was increased. W addition increased the FATT. 17 refs., 12 figs., 2 tabs.

  19. Effect of starting composition on formation of MoSi2–SiC ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 35; Issue 4. Effect of starting ... MoSi2–SiC nanocomposite powders were successfully synthesized by ball milling Mo, Si and graphite elemental powders. Effects of ... Mo5Si3 was formed during annealing as a product of a reaction between MoSi2 and excess graphite.

  20. Welding of Low Alloy Steel DIN 15Mo3 by MIG/MAG Spot

    OpenAIRE

    Nabeel K. Abid Al- Sahib

    2006-01-01

    ????? ????? ????? ????? ??????? ?????? ?? ????? ?????? ?????? ?????? ??????? ?????? ?????? (MIG/MAG spot) ???????? ??? ??????? ????? ?? ???? ???????? ????? ??? ???????? ?? ?????? ??????????? ??????? ???????? ????? ???? ??????? ??????? ????? ??? (DIN15Mo3) ?????? ?????? ?????? ?????? ?????? ?? ???? ???? ?????? ???????" ??? ?????? ??? ????. ????? ??????? ??????? ?????? ??? CO2 ????" ?? ??? ??????? ?? ???? ??????? ??????? ????? ?? ?????? ????? ?? ??? ???? ?? ????? (13%) ???? (4mm) ???? (2sec). ?...

  1. The Tribological Performance of CrMoN/MoS2 Solid Lubrication Coating on a Piston Ring

    Directory of Open Access Journals (Sweden)

    Yuelan Di

    2017-05-01

    Full Text Available In order to improve the tribological properties of an engine piston ring and enhance its service life, magnetron sputtering technology and low temperature ion sulphurizing treatment technology were used to prepare CrMoN/MoS2 solid lubricant coating on the surface of an engine piston ring. The morphologies and compositions of the surface and cross-section of the sulfuration layer were analyzed by field emission scanning electron microscopy (FESEM, and wear property under high load, high speed and high temperature conditions were tested by a SRV®4 friction and wear testing machine. The results show that the CrMoN/MoS2 composite coatings appear as a dense grain structure, and the coating is an ideal solid lubrication layer that possesses an excellent high temperature wear resistance, reducing the engine operating temperature abrasion effectively and prolonging the service life of the engine.

  2. Charge transfer and magnetization of a MoS2 monolayer at the Co(0001)/MoS2 interface

    Science.gov (United States)

    Garandel, T.; Arras, R.; Marie, X.; Renucci, P.; Calmels, L.

    2017-10-01

    The Co/MoS2 system may constitute a fundamental building block for future spintronic devices based on a single MoS2 transition metal dichalcogenide monolayer. Here, the hcp Co(0001)/MoS2 interface electronic structure as well as magnetic properties are investigated by first principles calculations based on the density functional theory. The charge transfer due to covalent bonding between S and Co atoms at the interface has been calculated for the lowest energy configuration obtained after optimization of the atomic coordinates. This charge transfer is different for majority and minority spin electrons, which induces a magnetization of the MoS2 layer bellow the Cobalt contact. The connection between the charge transfers at the interface and the modification of the magnetic properties is discussed.

  3. PtMo alloy and MoO(x)@Pt core-shell nanoparticles as highly CO-tolerant electrocatalysts.

    Science.gov (United States)

    Liu, Zhufang; Hu, Jenny E; Wang, Qi; Gaskell, Karen; Frenkel, Anatoly I; Jackson, Gregory S; Eichhorn, Bryan

    2009-05-27

    PtMo alloy and MoO(x)@Pt core-shell nanoparticles (NPs) were successfully synthesized by a chemical coreduction and sequential chemical reduction method, respectively. Both the carbon-supported alloy and core-shell NPs show substantially higher CO tolerance, compared to the commercialized E-TEK PtRu alloy and Pt catalyst. These novel nanocatalysts can be potentially used as highly CO-tolerant anode electrocatalysts in proton exchange membrane fuel cells.

  4. New findings on phosphodiesterases, MoPdeH and MoPdeL, in Magnaporthe oryzae revealed by structural analysis.

    Science.gov (United States)

    Yang, Li-Na; Yin, Ziyi; Zhang, Xi; Feng, Wanzhen; Xiao, Yuhan; Zhang, Haifeng; Zheng, Xiaobo; Zhang, Zhengguang

    2017-07-27

    The cyclic adenosine monophosphate (cAMP) signalling pathway mediates signal communication and sensing during infection-related morphogenesis in eukaryotes. Many studies have implicated cAMP as a critical mediator of appressorium development in the rice blast fungus, Magnaporthe oryzae. The cAMP phosphodiesterases, MoPdeH and MoPdeL, as key regulators of intracellular cAMP levels, play pleiotropic roles in cell wall integrity, cellular morphology, appressorium formation and infectious growth in M. oryzae. Here, we analysed the roles of domains of MoPdeH and MoPdeL separately or in chimeras. The results indicated that the HD and EAL domains of MoPdeH are indispensable for its phosphodiesterase activity and function. Replacement of the MoPdeH HD domain with the L1 and L2 domains of MoPdeL, either singly or together, resulted in decreased cAMP hydrolysis activity of MoPdeH. All of the transformants exhibited phenotypes similar to that of the ΔMopdeH mutant, but also revealed that EAL and L1 play additional roles in conidiation, and that L1 is involved in infectious growth. We further found that the intracellular cAMP level is important for surface signal recognition and hyphal autolysis. The intracellular cAMP level negatively regulates Mps1-MAPK and positively regulates Pmk1-MAPK in the rice blast fungus. Our results provide new information to better understand the cAMP signalling pathway in the development, differentiation and plant infection of the fungus. © 2017 BSPP AND JOHN WILEY & SONS LTD.

  5. Telecommunication networks

    CERN Document Server

    Iannone, Eugenio

    2011-01-01

    Many argue that telecommunications network infrastructure is the most impressive and important technology ever developed. Analyzing the telecom market's constantly evolving trends, research directions, infrastructure, and vital needs, Telecommunication Networks responds with revolutionized engineering strategies to optimize network construction. Omnipresent in society, telecom networks integrate a wide range of technologies. These include quantum field theory for the study of optical amplifiers, software architectures for network control, abstract algebra required to design error correction co

  6. Plasma-assisted synthesis of MoS2

    Science.gov (United States)

    Campbell, Philip M.; Perini, Christopher J.; Chiu, Johannes; Gupta, Atul; Ray, Hunter S.; Chen, Hang; Wenzel, Kevin; Snyder, Eric; Wagner, Brent K.; Ready, Jud; Vogel, Eric M.

    2018-03-01

    There has been significant interest in transition metal dichalcogenides (TMDs), including MoS2, in recent years due to their potential application in novel electronic and optical devices. While synthesis methods have been developed for large-area films of MoS2, many of these techniques require synthesis temperatures of 800 °C or higher. As a result of the thermal budget, direct synthesis requiring high temperatures is incompatible with many integrated circuit processes as well as flexible substrates. This work explores several methods of plasma-assisted synthesis of MoS2 as a way to lower the synthesis temperature. The first approach used is conversion of a naturally oxidized molybdenum thin film to MoS2 using H2S plasma. Conversion is demonstrated at temperatures as low as 400 °C, and the conversion is enabled by hydrogen radicals which reduce the oxidized molybdenum films. The second method is a vapor phase reaction incorporating thermally evaporated MoO3 exposed to a direct H2S plasma, similar to chemical vapor deposition (CVD) synthesis of MoS2. Synthesis at 400 °C results in formation of super-stoichiometric MoS2 in a beam-interrupted growth process. A final growth method relies on a cyclical process in which a small amount of Mo is sputtered onto the substrate and is subsequently sulfurized in a H2S plasma. Similar results could be realized using an atomic layer deposition (ALD) process to deposit the Mo film. Compared to high temperature synthesis methods, the lower temperature samples are lower quality, potentially due to poor crystallinity or higher defect density in the films. Temperature-dependent conductivity measurements are consistent with hopping conduction in the plasma-assisted synthetic MoS2, suggesting a high degree of disorder in the low-temperature films. Optimization of the plasma-assisted synthesis process for slower growth rate and better stoichiometry is expected to lead to high quality films at low growth temperature.

  7. Vertical MoSe2–MoO x p–n heterojunction and its application in optoelectronics

    Science.gov (United States)

    Chen, Xiaoshuang; Liu, Guangbo; Hu, Yunxia; Cao, Wenwu; Hu, PingAn; Hu, Wenping

    2018-01-01

    The hybrid n-type 2D transition-metal dichalcogenide (TMD)/p-type oxide van der Waals (vdW) heterojunction nanosheets consist of 2D layered MoSe2 (the n-type 2D material) and MoO x (the p-type oxide) which are grown on SiO2/Si substrates for the first time via chemical vapor deposition technique, displaying the regular hexagon structures with the average length dimension of sides of ∼8 μm. Vertical MoSe2–MoO x p–n heterojunctions demonstrate obviously current-rectifying characteristic, and it can be tuned via gate voltage. What is more, the photodetector based on vertical MoSe2–MoO x heterojunctions displays optimal photoresponse behavior, generating the responsivity, detectivity, and external quantum efficiency to 3.4 A W‑1, 0.85 × 108 Jones, and 1665.6%, respectively, at V ds = 5 V with the light wavelength of 254 nm under 0.29 mW cm‑2. These results furnish a building block on investigating the flexible and transparent properties of vdW and further optimizing the structure of the devices for better optoelectronic and electronic performance.

  8. Tetracarbonylbis(η5-cyclopentadienylbis(diphenylphosphinedimolybdenum(Mo—Mo hexane solvate

    Directory of Open Access Journals (Sweden)

    David R. Tyler

    2008-07-01

    Full Text Available The title compound, [Mo2(C5H52(C12H11P2(CO4]·C6H14, is a centrosymmetric Mo complex in which two Mo atoms are connected by an Mo—Mo bond [3.2072 (12 Å]. Each Mo atom is coordinated by an η5-cyclopentadienyl ligand, two carbonyl ligands and a diphenylphosphine ligand in a piano-stool fashion.

  9. In-Plane Mosaic Potential Growth of Large-Area 2D Layered Semiconductors MoS2-MoSe2 Lateral Heterostructures and Photodetector Application.

    Science.gov (United States)

    Chen, Xiaoshuang; Qiu, Yunfeng; Yang, Huihui; Liu, Guangbo; Zheng, Wei; Feng, Wei; Cao, Wenwu; Hu, Wenping; Hu, PingAn

    2017-01-18

    Considering the unique layered structure and novel optoelectronic properties of individual MoS2 and MoSe2, as well as the quantum coherence or donor-acceptor coupling effects between these two components, rational design and artificial growth of in-plane mosaic MoS2/MoSe2 lateral heterojunctions film on conventional amorphous SiO2/Si substrate are in high demand. In this article, large-area, uniform, high-quality mosaic MoS2/MoSe2 lateral heterojunctions film was successfully grown on SiO2/Si substrate for the first time by chemical vapor deposition (CVD) technique. MoSe2 film was grown along MoS2 triangle edges and occupied the blanks of the substrate, finally leading to the formation of mosaic MoS2/MoSe2 lateral heterojunctions film. The composition and microstructure of mosaic MoS2/MoSe2 lateral heterojunctions film were characterized by various analytic techniques. Photodetectors based on mosaic MoS2/MoSe2 lateral heterojunctions film, triangular MoS2 monolayer, and multilayer MoSe2 film are systematically investigated. The mosaic MoS2/MoSe2 lateral heterojunctions film photodetector exhibited optimal photoresponse performance, giving rise to responsivity, detectivity, and external quantum efficiency (EQE) up to 1.3 A W(-1), 2.6 × 10(11) Jones, and 263.1%, respectively, under the bias voltage of 5 V with 0.29 mW cm(-2) (610 nm), possibly due to the matched band alignment of MoS2 and MoSe2 and strong donor-acceptor delocalization effect between them. Taking into account the similar edge conditions of transition metal dichalcogenides (TMDCs), such a facile and reliable approach might open up a unique route for preparing other 2D mosaic lateral heterojunctions films in a manipulative manner. Furthermore, the mosaic lateral heterojunctions film like MoS2/MoSe2 in the present work will be a promising candidate for optoelectronic fields.

  10. Coated U(Mo) Fuel: As-Fabricated Microstructures

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel Perez; Dennis D. Keiser, Jr.; Ann Leenaers; Sven Van den Berghe; Tom Wiencek

    2014-04-01

    As part of the development of low-enriched uranium fuels, fuel plates have recently been tested in the BR-2 reactor as part of the SELENIUM experiment. These fuel plates contained fuel particles with either Si or ZrN thin film coating (up to 1 µm thickness) around the U-7Mo fuel particles. In order to best understand irradiation performance, it is important to determine the starting microstructure that can be observed in as-fabricated fuel plates. To this end, detailed microstructural characterization was performed on ZrN and Si-coated U-7Mo powder in samples taken from AA6061-clad fuel plates fabricated at 500°C. Of interest was the condition of the thin film coatings after fabrication at a relatively high temperature. Both scanning electron microscopy and transmission electron microscopy were employed. The ZrN thin film coating was observed to consist of columns comprised of very fine ZrN grains. Relatively large amounts of porosity could be found in some areas of the thin film, along with an enrichment of oxygen around each of the the ZrN columns. In the case of the pure Si thin film coating sample, a (U,Mo,Al,Si) interaction layer was observed around the U-7Mo particles. Apparently, the Si reacted with the U-7Mo and Al matrix during fuel plate fabrication at 500°C to form this layer. The microstructure of the formed layer is very similar to those that form in U-7Mo versus Al-Si alloy diffusion couples annealed at higher temperatures and as-fabricated U-7Mo dispersion fuel plates with Al-Si alloy matrix fabricated at 500°C.

  11. Interconnected networks

    CERN Document Server

    2016-01-01

    This volume provides an introduction to and overview of the emerging field of interconnected networks which include multi layer or multiplex networks, as well as networks of networks. Such networks present structural and dynamical features quite different from those observed in isolated networks. The presence of links between different networks or layers of a network typically alters the way such interconnected networks behave – understanding the role of interconnecting links is therefore a crucial step towards a more accurate description of real-world systems. While examples of such dissimilar properties are becoming more abundant – for example regarding diffusion, robustness and competition – the root of such differences remains to be elucidated. Each chapter in this topical collection is self-contained and can be read on its own, thus making it also suitable as reference for experienced researchers wishing to focus on a particular topic.

  12. Synthesis of MoS2 and MoO2 for their applications in H2 generation and lithium ion batteries: a review

    Science.gov (United States)

    Zhao, Yufei; Zhang, Yuxia; Yang, Zhiyu; Yan, Yiming; Sun, Kening

    2013-01-01

    Scientists increasingly witness the applications of MoS2 and MoO2 in the field of energy conversion and energy storage. On the one hand, MoS2 and MoO2 have been widely utilized as promising catalysts for electrocatalytic or photocatalytic hydrogen evolution in aqueous solution. On the other hand, MoS2 and MoO2 have also been verified as efficient electrode material for lithium ion batteries. In this review, the synthesis, structure and properties of MoS2 and MoO2 are briefly summarized according to their applications for H2 generation and lithium ion batteries. Firstly, we overview the recent advancements in the morphology control of MoS2 and MoO2 and their applications as electrocatalysts for hydrogen evolution reactions. Secondly, we focus on the photo-induced water splitting for H2 generation, in which MoS2 acts as an important co-catalyst when combined with other semiconductor catalysts. The newly reported research results of the significant functions of MoS2 nanocomposites in photo-induced water splitting are presented. Thirdly, we introduce the advantages of MoS2 and MoO2 for their enhanced cyclic performance and high capacity as electrode materials of lithium ion batteries. Recent key achievements in MoS2- and MoO2-based lithium ion batteries are highlighted. Finally, we discuss the future scope and the important challenges emerging from these fascinating materials. PMID:27877584

  13. Probing the Interlayer Exciton Physics in a MoS2/MoSe2/MoS2 van der Waals Heterostructure

    Science.gov (United States)

    Baranowski, M.; Surrente, A.; Klopotowski, L.; Urban, J. M.; Zhang, N.; Maude, D. K.; Wiwatowski, K.; Mackowski, S.; Kung, Y. C.; Dumcenco, D.; Kis, A.; Plochocka, P.

    2017-10-01

    Stacking atomic monolayers of semiconducting transition metal dichalcogenides (TMDs) has emerged as an effective way to engineer their properties. In principle, the staggered band alignment of TMD heterostructures should result in the formation of inter-layer excitons with long lifetimes and robust valley polarization. However, these features have been observed simultaneously only in MoSe$_2$/WSe$_2$ heterostructures. Here we report on the observation of long lived inter-layer exciton emission in a MoS$_2$/MoSe$_2$/MoS$_2$ trilayer van der Waals heterostructure. The inter-layer nature of the observed transition is confirmed by photoluminescence spectroscopy, as well as by analyzing the temporal, excitation power and temperature dependence of the inter-layer emission peak. The observed complex photoluminescence dynamics suggests the presence of quasi-degenerate momentum-direct and momentum-indirect bandgaps. We show that circularly polarized optical pumping results in long lived valley polarization of inter-layer exciton. Intriguingly, the inter-layer exciton photoluminescence has helicity opposite to the excitation. Our results show that through a careful choice of the TMDs forming the van der Waals heterostructure it is possible to control the circular polarization of the inter-layer exciton emission.

  14. Flawed MoO2 belts transformed from MoO3 on a graphene template for the hydrogen evolution reaction.

    Science.gov (United States)

    Wu, Longfei; Wang, Xinsheng; Sun, Yupeng; Liu, Yang; Li, Jinghong

    2015-04-28

    A simple and effective electrostatic method has been used to attach MoO3 belts onto a graphene template. The MoO3/graphene composite was annealed under a H2/Ar atmosphere; the obtained MoO2 maintained its original structure and exhibited microstructures such as flaws, etc. We investigated the electrocatalytic behavior of the MoO2/graphene composite towards the hydrogen evolution reaction.

  15. Probing the Interlayer Exciton Physics in a MoS2/MoSe2/MoS2van der Waals Heterostructure.

    Science.gov (United States)

    Baranowski, M; Surrente, A; Klopotowski, L; Urban, J M; Zhang, N; Maude, D K; Wiwatowski, K; Mackowski, S; Kung, Y C; Dumcenco, D; Kis, A; Plochocka, P

    2017-10-11

    Stacking atomic monolayers of semiconducting transition metal dichalcogenides (TMDs) has emerged as an effective way to engineer their properties. In principle, the staggered band alignment of TMD heterostructures should result in the formation of interlayer excitons with long lifetimes and robust valley polarization. However, these features have been observed simultaneously only in MoSe 2 /WSe 2 heterostructures. Here we report on the observation of long-lived interlayer exciton emission in a MoS 2 /MoSe 2 /MoS 2 trilayer van der Waals heterostructure. The interlayer nature of the observed transition is confirmed by photoluminescence spectroscopy, as well as by analyzing the temporal, excitation power, and temperature dependence of the interlayer emission peak. The observed complex photoluminescence dynamics suggests the presence of quasi-degenerate momentum-direct and momentum-indirect bandgaps. We show that circularly polarized optical pumping results in long-lived valley polarization of interlayer exciton. Intriguingly, the interlayer exciton photoluminescence has helicity opposite to the excitation. Our results show that through a careful choice of the TMDs forming the van der Waals heterostructure it is possible to control the circular polarization of the interlayer exciton emission.

  16. Role of vacancies in tuning the electronic properties of Au-MoS{sub 2} contact

    Energy Technology Data Exchange (ETDEWEB)

    Su, Jie, E-mail: sujie0105@mail.nwpu.edu.cn, E-mail: lpfeng@nwpu.edu.cn; Li, Ning; Zhang, Yingying; Feng, Liping, E-mail: sujie0105@mail.nwpu.edu.cn, E-mail: lpfeng@nwpu.edu.cn; Liu, Zhengtang [State Key Lab of Solidification Processing, College of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an, Shaanxi, 710072 (China)

    2015-07-15

    Understanding the electronic properties between molybdenum disulfide (MoS{sub 2}) and metal electrodes is vital for the designing and realization of nanoelectronic devices. In this work, influence of intrinsic vacancies in monolayer MoS{sub 2} on the electronic structure and electron properties of Au-MoS{sub 2} contacts is investigated using first-principles calculations. Upon formation of vacancies in monolayer MoS{sub 2}, both tunnel barriers and Schottky Barriers between metal Au and monolayer MoS{sub 2} are decreased. Perfect Au-MoS{sub 2} top contact exhibits physisorption interface with rectifying character, whereas Au-MoS{sub 2} contact with Mo-vacancy shows chemisorption interface with Ohmic character. Partial density of states and electron density of defective Au-MoS{sub 2} top contacts are much higher than those of perfect one, indicating the lower contact resistance and higher electron injection efficiency of defective Au-MoS{sub 2} top contacts. Notably, Mo-vacancy in monolayer MoS{sub 2} is beneficial to get high quality p-type Au-MoS{sub 2} top contact, whereas S-vacancy in monolayer MoS{sub 2} is favorable to achieve high quality n-type Au-MoS{sub 2} top contact. Our results provide guidelines for designing and fabrication of novel 2D nanoelectronic devices.

  17. Role of vacancies in tuning the electronic properties of Au-MoS2 contact

    Directory of Open Access Journals (Sweden)

    Jie Su

    2015-07-01

    Full Text Available Understanding the electronic properties between molybdenum disulfide (MoS2 and metal electrodes is vital for the designing and realization of nanoelectronic devices. In this work, influence of intrinsic vacancies in monolayer MoS2 on the electronic structure and electron properties of Au-MoS2 contacts is investigated using first-principles calculations. Upon formation of vacancies in monolayer MoS2, both tunnel barriers and Schottky Barriers between metal Au and monolayer MoS2 are decreased. Perfect Au-MoS2 top contact exhibits physisorption interface with rectifying character, whereas Au-MoS2 contact with Mo-vacancy shows chemisorption interface with Ohmic character. Partial density of states and electron density of defective Au-MoS2 top contacts are much higher than those of perfect one, indicating the lower contact resistance and higher electron injection efficiency of defective Au-MoS2 top contacts. Notably, Mo-vacancy in monolayer MoS2 is beneficial to get high quality p-type Au-MoS2 top contact, whereas S-vacancy in monolayer MoS2 is favorable to achieve high quality n-type Au-MoS2 top contact. Our results provide guidelines for designing and fabrication of novel 2D nanoelectronic devices.

  18. Structural characterization of biomedical Co–Cr–Mo components produced by direct metal laser sintering

    Energy Technology Data Exchange (ETDEWEB)

    Barucca, G., E-mail: g.barucca@univpm.it [SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona (Italy); Santecchia, E.; Majni, G. [SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona (Italy); Girardin, E. [DISCO, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona (Italy); Bassoli, E.; Denti, L.; Gatto, A. [DIMeC, University of Modena and Reggio Emilia, via Vignolese 905/B, Modena 41125 (Italy); Iuliano, L. [DISPEA, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino (Italy); Moskalewicz, T. [Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków (Poland); Mengucci, P. [SIMAU, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona (Italy)

    2015-03-01

    Direct metal laser sintering (DMLS) is a technique to manufacture complex functional mechanical parts from a computer-aided design (CAD) model. Usually, the mechanical components produced by this procedure show higher residual porosity and poorer mechanical properties than those obtained by conventional manufacturing techniques. In this work, a Co–Cr–Mo alloy produced by DMLS with a composition suitable for biomedical applications was submitted to hardness measurements and structural characterization. The alloy showed a hardness value remarkably higher than those commonly obtained for the same cast or wrought alloys. In order to clarify the origin of this unexpected result, the sample microstructure was investigated by X-ray diffraction (XRD), electron microscopy (SEM and TEM) and energy dispersive microanalysis (EDX). For the first time, a homogeneous microstructure comprised of an intricate network of thin ε (hcp)-lamellae distributed inside a γ (fcc) phase was observed. The ε-lamellae grown on the {111}{sub γ} planes limit the dislocation slip inside the γ (fcc) phase, causing the measured hardness increase. The results suggest possible innovative applications of the DMLS technique to the production of mechanical parts in the medical and dental fields. - Highlights: • Samples of a Co–Cr–Mo biomedical alloy were produced by direct metal laser sintering. • Hardness values unexpectedly high were attributed to a peculiar microstructure. • Fine lamellae of the ε-phase alternated to the γ-phase were observed for the first time. • A nucleation and growth model for the observed microstructure is proposed.

  19. Tuneable photoconductivity and mobility enhancement in printed MoS2/graphene composites

    Science.gov (United States)

    Kelly, Adam G.; Murphy, Conor; Vega-Mayoral, Victor; Harvey, Andrew; Sajad Esmaeily, Amir; Hallam, Toby; McCloskey, David; Coleman, Jonathan N.

    2017-12-01

    With the aim of increasing carrier mobility in nanosheet-network devices, we have investigated MoS2-graphene composites as active regions in printed photodetectors. Combining liquid exfoliation and inkjet-printing, we fabricated all-printed photodetectors with graphene electrodes and MoS2-graphene composite channels with various graphene mass fractions (0  ⩽  M f  ⩽  16 wt%). The increase in channel dark conductivity with M f was consistent with percolation theory for composites below the percolation threshold. While the photoconductivity increased with graphene content, it did so more slowly than the dark conductivity, such that the fractional photoconductivity decayed rapidly with increasing M f. We propose that both mobility and dark carrier density increase with graphene content according to percolation-like scaling laws, while photo-induced carrier density is essentially independent of graphene loading. This leads to percolation-like scaling laws for both photoconductivity and fractional photoconductivity—in excellent agreement with the data. These results imply that channel mobility and carrier density increase up to 100-fold with the addition of 16 wt% graphene.

  20. Single crystal monolayer MoS2 triangles with wafer-scale spatial uniformity by MoO3 pre-deposited chemical vapor deposition

    Science.gov (United States)

    Cheng, Zhaofang; Xia, Minggang; Hu, Ruixue; Liang, Chunping; Liang, Gongying; Zhang, Shengli

    2017-12-01

    Two-dimensional transition metal dichalcogenides (TMDs) show a potential application in photoelectric device due to their excellent electrical and optical properties. Here, we report that the MoO3 pre-deposited chemical vapor deposition (CVD) is used to synthesize single crystal monolayer MoS2 triangles on 4 in. wafer. We found that the wafer-scale uniformity of MoS2 can be greatly improved by regularly depositing MoO3 particles on substrate before CVD growth. Therefore, a piece of cleanroom wiper was used as a template for implementing precise control of MoO3 pre-deposition. We found that the optimal deposition size of MoO3 particles and the distance between MoO3 particles are about 15 μm and 0.9 mm, respectively. Both microscopic and spectroscopic characterization results demonstrate that the as-grown MoS2 is highly uniform in space distribution and crystal structure. The electronic performance of MoS2 synthesized by our method is comparable to or even slightly better than those in common CVD samples. The role of MoO3 pre-deposition is not only to effectively control the MoS2 nucleation density but also to overcome poor diffusion of MoO3 source. Our method is expected to accelerate the industrial synthesis of the atomically thin TMD materials.

  1. Preparation of single-crystal spherical γ-Mo2N by temperature-programmed reaction between β-MoO3 and NH3

    Science.gov (United States)

    Wang, Lu; Zhang, Guo-Hua; Chou, Kuo-Chih

    2017-10-01

    In the present wok, single-crystalline spherical γ-Mo2N powders was successfully prepared by the temperature-programmed reaction of single-crystal spherical β-MoO3 with NH3 in the temperature ranges of 1013-1073 K. Herein, the Mo source used was monoclinic system, β-MoO3, a metastable phase of MoO3. It is found that the characterizations of the as-prepared γ-Mo2N powders are strongly depended on the selection of the MoO3 precursor. In other words, the as-prepared γ-Mo2N powders inherited the shape, size and structure of the used β-MoO3 precursors upon reaction with NH3. In order to make a comparison, β-MoO3 was also reduced by the mixed gases of N2 and H2 with the flow rate ratio of 1:3 at the identical conditions. It was found that pure β-Mo2N polycrystalline can be obtained when the temperature was 1013 K; while further increasing the reaction temperature, metal Mo powder will be turned up.

  2. Controllable growth of monolayer MoS2 by chemical vapor deposition via close MoO2 precursor for electrical and optical applications.

    Science.gov (United States)

    Xie, Yong; Wang, Zhan; Zhan, Yongjie; Zhang, Peng; Wu, Ruixue; Jiang, Teng; Wu, Shiwei; Wang, Hong; Zhao, Ying; Nan, Tang; Ma, Xiaohua

    2017-02-24

    MoO2 is used as a new source material for the growth of large area and high optical quality monolayer MoS2. However, a systematic study of the growth parameters is still missing and large-area growth of discreet single crystals is still challenging. Hereby, we report the shape evolution of monolayer growth of MoS2 and develop a methodology to achieve centimeter-scaled discrete MoS2 by adopting MoO2 as Mo source material in an atmospheric-pressure chemical vapor deposition process. Our results indicate the growth of monolayer MoS2 could benefit from the precise control of the introduction time of sulfur and the S/MoO2 ratio in experiments. Micro-Raman and photoluminescence spectra confirm the properties of the material. E-beam lithography was utilized to make contact with the as-grown MoS2 located at the selective area. The electrical properties of MoS2 with different morphologies were compared. In the end, the persistent photoconductivity properties of monolayer MoS2 were emphasized and the underlying mechanism was proposed. These studies demonstrate a better understanding of the growth and application of MoS2-based 2D materials.

  3. Network maintenance

    CERN Multimedia

    IT Department

    2009-01-01

    A site wide network maintenance has been scheduled for Saturday 28 February. Most of the network devices of the General Purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites along this day. This upgrade will not affect: the Computer centre itself, building 613, the Technical Network and the LHC experiments dedicated networks at the pits. Should you need more details on this intervention, please contact Netops by phone 74927 or email mailto:Netops@cern.ch. IT/CS Group

  4. Network maintenance

    CERN Multimedia

    GS Department

    2009-01-01

    A site-wide network maintenance operation has been scheduled for Saturday 28 February. Most of the network devices of the general purpose network will be upgraded to a newer software version, in order to improve our network monitoring capabilities. This will result in a series of short (2-5 minutes) random interruptions everywhere on the CERN sites throughout the day. This upgrade will not affect the Computer Centre itself, Building 613, the Technical Network and the LHC experiments, dedicated networks at the pits. For further details of this intervention, please contact Netops by phone 74927 or e-mail mailto:Netops@cern.ch. IT/CS Group

  5. Redes de aprendizaje, aprendizaje en red Learning Networks, Networked Learning

    Directory of Open Access Journals (Sweden)

    Peter Sloep

    2011-10-01

    Full Text Available Las redes de aprendizaje (Learning Networks son redes sociales en línea mediante las cuales los participantes comparten información y colaboran para crear conocimiento. De esta manera, estas redes enriquecen la experiencia de aprendizaje en cualquier contexto de aprendizaje, ya sea de educación formal (en escuelas o universidades o educación no-formal (formación profesional. Aunque el concepto de aprendizaje en red suscita el interés de diferentes actores del ámbito educativo, aún existen muchos interrogantes sobre cómo debe diseñarse el aprendizaje en red para facilitar adecuadamente la educación y la formación. El artículo toma este interrogante como punto de partida, y posteriormente aborda cuestiones como la dinámica de la evolución de las redes de aprendizaje, la importancia de fomentar la confianza entre los participantes y el papel central que desempeña el perfil de usuario en la construcción de la confianza, así como el apoyo entre compañeros. Además, se elabora el proceso de diseño de una red de aprendizaje, y se describe un ejemplo en el contexto universitario. Basándonos en la investigación que actualmente se lleva a cabo en nuestro propio centro y en otros lugares, el capítulo concluye con una visión del futuro de las redes de aprendizaje.Learning Networks are on-line social networks through which users share knowledge with each other and jointly develop new knowledge. This way, Learning Networks may enrich the experience of formal, school-based learning and form a viable setting for professional development. Although networked learning enjoys an increasing interest, many questions remain on how exactly learning in such networked contexts can contribute to successful education and training. Put differently, how should networked learning be designed best to facilitate education and training? Taking this as its point of departure, the chapter addresses such issues as the dynamic evolution of Learning Networks

  6. Integrated circuits based on bilayer MoS₂ transistors.

    Science.gov (United States)

    Wang, Han; Yu, Lili; Lee, Yi-Hsien; Shi, Yumeng; Hsu, Allen; Chin, Matthew L; Li, Lain-Jong; Dubey, Madan; Kong, Jing; Palacios, Tomas

    2012-09-12

    Two-dimensional (2D) materials, such as molybdenum disulfide (MoS(2)), have been shown to exhibit excellent electrical and optical properties. The semiconducting nature of MoS(2) allows it to overcome the shortcomings of zero-bandgap graphene, while still sharing many of graphene's advantages for electronic and optoelectronic applications. Discrete electronic and optoelectronic components, such as field-effect transistors, sensors, and photodetectors made from few-layer MoS(2) show promising performance as potential substitute of Si in conventional electronics and of organic and amorphous Si semiconductors in ubiquitous systems and display applications. An important next step is the fabrication of fully integrated multistage circuits and logic building blocks on MoS(2) to demonstrate its capability for complex digital logic and high-frequency ac applications. This paper demonstrates an inverter, a NAND gate, a static random access memory, and a five-stage ring oscillator based on a direct-coupled transistor logic technology. The circuits comprise between 2 to 12 transistors seamlessly integrated side-by-side on a single sheet of bilayer MoS(2). Both enhancement-mode and depletion-mode transistors were fabricated thanks to the use of gate metals with different work functions.

  7. Stress reduction of Mo/Si multilayer structures

    CERN Document Server

    Andreev, S S; Suslov, L A; Yablonsky, A N; Zuev, S Y

    2001-01-01

    Due to the stringent surface figure requirements for the multilayer-coated optics in an extreme ultraviolet (EUV) projection lithography system make it desirable to minimize deformation due to the multilayer structure stress. However, the stress must be reduced or compensated without reducing the EUV reflectivity, since the reflectivity has a strong impact on the throughput of the EUV lithography tool. In this work, we evaluate techniques for stress reduction and compensation as applied to multilayer Mo/Si structures. The experimental research of multilayer Mo/Si-structures by the methods of X-ray reflectometry and electron microscopy has shown that reflectivity of Mo/Si-structures largely depends on the parameter gamma=d sub M sub o /d and in the spectral region of 13-13.7 nm reaches the maximum value at gamma approx 0.42-0.44. The measured film stress for Mo/Si films with EUV reflectances near 66-69% at 13.3 nm is approximately -250 MPa (compressive). Variation of the Mo-to-Si ratio can be used to reduce th...

  8. Optical Attenuation in MoNA and LISA Detector Elements

    Science.gov (United States)

    Rice, Logan; Wong, Jonathan; MoNA Collaboration

    2011-10-01

    The MoNA collaboration is a research group of students and faculty from 13 primarily undergraduate institutions, with detectors at the NSCL: MoNA (Modular Neutron Array) and the newly-built LISA (Large multi-Institutional Scintillating Array). These arrays each have 144 plastic scintillating bars. When a neutron collides with a hydrogen nucleus within the plastic, photomultiplier tubes at either end of the bar detect the scintillation photons. Their arrival times are used to determine the position of the event, but as the light travels through the detector it loses intensity exponentially. How dramatic this loss is can be described by a parameter called the attenuation length, with larger attenuation lengths corresponding to lower loss. Recently the MoNA collaboration conducted its LISA commissioning experiment investigating two-neutron decay states of 25O. As a part of LISA's commissioning, we measured the attenuation lengths of the individual detector bars that make up the LISA array and compared these lengths with those of the older MoNA array. We found that the LISA bars had a larger attenuation length on average with impacts on detector efficiency and effective threshold. The authors wish to acknowledge the contributions of the members of the MoNA Collaboration.

  9. Network Ambivalence

    Directory of Open Access Journals (Sweden)

    Patrick Jagoda

    2015-08-01

    Full Text Available The language of networks now describes everything from the Internet to the economy to terrorist organizations. In distinction to a common view of networks as a universal, originary, or necessary form that promises to explain everything from neural structures to online traffic, this essay emphasizes the contingency of the network imaginary. Network form, in its role as our current cultural dominant, makes scarcely imaginable the possibility of an alternative or an outside uninflected by networks. If so many things and relationships are figured as networks, however, then what is not a network? If a network points towards particular logics and qualities of relation in our historical present, what others might we envision in the future? In  many ways, these questions are unanswerable from within the contemporary moment. Instead of seeking an avant-garde approach (to move beyond networks or opting out of networks (in some cases, to recover elements of pre-networked existence, this essay proposes a third orientation: one of ambivalence that operates as a mode of extreme presence. I propose the concept of "network aesthetics," which can be tracked across artistic media and cultural forms, as a model, style, and pedagogy for approaching interconnection in the twenty-first century. The following essay is excerpted from Network Ambivalence (Forthcoming from University of Chicago Press. 

  10. Highly efficient hydrogen evolution based on Ni3S4@MoS2 hybrids supported on N-doped reduced graphene oxide

    Science.gov (United States)

    Xu, Xiaobing; Zhong, Wei; Wu, Liqian; Sun, Yuan; Wang, Tingting; Wang, Yuanqi; Du, Youwei

    2018-01-01

    Hydrogen evolution reaction (HER) through water splitting at low overpotential is an appealing technology to produce renewable energy, wherein the design of stable electrocatalysts is very critical. To achieve optimal electrochemical performance, a highly efficient and stable noble-metal-free HER catalyst is synthesized by means of a facile hydrothermal co-synthesis. It consists of Ni3S4 nanosheets and MoS2 nanolayers supported on N-doped reduced graphene oxide (Ni3S4/MoS2@N-rGO). The optimized sample provides a large amount of active sites that benefit electron transfer in 3D conductive networks. Thanks to the strong synergistic effect in the catalyst network, we achieved a low overpotential of 94 mV, a small Tafel slope of 56 mV/dec and remarkable durability in an acidic medium.

  11. Network neuroscience.

    Science.gov (United States)

    Bassett, Danielle S; Sporns, Olaf

    2017-02-23

    Despite substantial recent progress, our understanding of the principles and mechanisms underlying complex brain function and cognition remains incomplete. Network neuroscience proposes to tackle these enduring challenges. Approaching brain structure and function from an explicitly integrative perspective, network neuroscience pursues new ways to map, record, analyze and model the elements and interactions of neurobiological systems. Two parallel trends drive the approach: the availability of new empirical tools to create comprehensive maps and record dynamic patterns among molecules, neurons, brain areas and social systems; and the theoretical framework and computational tools of modern network science. The convergence of empirical and computational advances opens new frontiers of scientific inquiry, including network dynamics, manipulation and control of brain networks, and integration of network processes across spatiotemporal domains. We review emerging trends in network neuroscience and attempt to chart a path toward a better understanding of the brain as a multiscale networked system.

  12. Organizational Networks

    DEFF Research Database (Denmark)

    Grande, Bård; Sørensen, Ole Henning

    1998-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept of organizational network are identified and critically discussed. Special focus is placed on how information and communication technologies as communication mediators and cognitive pictures influence...

  13. Network workshop

    DEFF Research Database (Denmark)

    Bruun, Jesper; Evans, Robert Harry

    2014-01-01

    This paper describes the background for, realisation of and author reflections on a network workshop held at ESERA2013. As a new research area in science education, networks offer a unique opportunity to visualise and find patterns and relationships in complicated social or academic network data...... research community. With this workshop, participants were offered a way into network science based on authentic educational research data. The workshop was constructed as an inquiry lesson with emphasis on user autonomy. Learning activities had participants choose to work with one of two cases of networks...... network methodology in one’s research might supersede the perceived benefits of doing so. As a response to that problem, we argue that workshops can act as a road towards meaningful engagement with networks and highlight that network methodology promises new ways of interpreting data to answer questions...

  14. Social Networks

    OpenAIRE

    Martí, Joan; Zenou, Yves

    2009-01-01

    We survey the literature on social networks by putting together the economics, sociological and physics/applied mathematics approaches, showing their similarities and differences. We expose, in particular, the two main ways of modeling network formation. While the physics/applied mathematics approach is capable of reproducing most observed networks, it does not explain why they emerge. On the contrary, the economics approach is very precise in explaining why networks emerge but does a poor jo...

  15. High activity of Pt(4)Mo alloy for the electrochemical oxidation of formic acid.

    Science.gov (United States)

    Gojković, Snezana Lj; Tripković, Amalija V; Stevanović, Rade M; Krstajić, Nedeljko V

    2007-12-04

    Surface processes on Pt4Mo alloy well-defined by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were studied in acid solution by cyclic voltammetry. It was established that Mo in the alloy is much more resistant toward electrochemical dissolution than pure Mo. During the potential cycling of Pt4Mo surfaces in completely quiescent electrolyte, hydrous Mo-oxide could be generated on Mo sites. Investigation of the formic acid oxidation revealed that this type of Mo-oxide enhances the reaction rate by more than 1 order of magnitude with respect to pure Pt. Surface poisoning by CO(ads) is significantly lower on Pt4Mo alloy than on pure Pt. The effect of hydrous Mo-oxide on the HCOOH oxidation rate was explained through the facilitated removal of the poisoning species and through its possible influence on the intrinsic rate of the direct reaction path.

  16. E’’ Raman Mode in Thermal Strain-Fractured CVD-MoS2

    Directory of Open Access Journals (Sweden)

    Di Wu

    2016-11-01

    Full Text Available Molybdenum disulfide (MoS2 has recently attracted considerable interests due to its unique properties and potential applications. Chemical vapor deposition (CVD method is used widely to grow large-area and high-quality MoS2 single crystals. Here, we report our investigation on thermal strain-fractured (SF single crystalline MoS2, oxidation-fractured MoS2, and normal MoS2 by atomic force microscopy (AFM, Raman and photoluminescence (PL measurements. Several new Raman modes are observed for SF-MoS2. The band gap of SF-MoS2 is enlarged by 150 meV and the PL intensity is reduced substantially. These results imply that a structural transformation occurs in SF-MoS2. Our findings here are useful for the design of MoS2-based nanocatalysts with relative high catalytic activity.

  17. Anisotropic magnetic property of nanocomposite Nd2Fe14B/Mo/α-Fe multilayer films

    Science.gov (United States)

    Kobayashi, K.; Ogawa, D.; Koike, K.; Kato, H.; Oogane, M.; Miyazaki, T.; Ando, Y.; Itakura, M.

    2017-10-01

    We fabricated the MgO(100)/Mo/[Nd2Fe14B/Mo/Fe/Mo]5/Mo multilayer films, in which we tried to avoid the negative J ex interfaces and thermal diffusion between Nd2Fe14B and α–Fe layers by forming the stacked structure with ultra thin Mo interlayer. The films without Mo interlayer showed isotropic magnetic properties, while films with Mo interlayer thickness t Mo = 1 nm exhibited the perpendicular anisotropy with the coercivity of 7 kOe. Shapes for the major loop and the first order reversal curves (FORCs) suggested an existence of positive exchange coupling between the Nd-Fe-B and the α–Fe layers via the 1 nm thick Mo interlayer.

  18. MoS2 nanosheet photodetectors with ultrafast response

    Science.gov (United States)

    Tang, Weiwei; Liu, Changlong; Wang, Lin; Chen, Xiaoshuang; Luo, Man; Guo, Wanlong; Wang, Shao-Wei; Lu, Wei

    2017-10-01

    Two-dimensional layered materials, such as molybdenum disulfide, are emerging as an exciting material system for future electronics due to their unique electronic properties and atomically thin geometry. In this work, MoS2-based FETs are fabricated using mechanical cleavage and standard photolithographic and metal evaporation techniques, and the detector exhibits a good ohmic contact. We show that the multilayer molybdenum disulfide photodetector has a fast photoresponse as short as 42 μs. The fast photodetector response is due to the decrease in the trap states in MoS2 flakes compared to monolayer MoS2, making its photoresponse time close to its intrinsic response. The large photocurrent with the responsivity and external quantum efficiency of 59 A/W and 13 800% for the wavelength of 532 nm was also measured. The fast response time, high responsivity, and the ease of fabrication of these devices make them important components for future optoelectronic devices.

  19. Single-layer MoS2 electronics.

    Science.gov (United States)

    Lembke, Dominik; Bertolazzi, Simone; Kis, Andras

    2015-01-20

    CONSPECTUS: Atomic crystals of two-dimensional materials consisting of single sheets extracted from layered materials are gaining increasing attention. The most well-known material from this group is graphene, a single layer of graphite that can be extracted from the bulk material or grown on a suitable substrate. Its discovery has given rise to intense research effort culminating in the 2010 Nobel Prize in physics awarded to Andre Geim and Konstantin Novoselov. Graphene however represents only the proverbial tip of the iceberg, and increasing attention of researchers is now turning towards the veritable zoo of so-called "other 2D materials". They have properties complementary to graphene, which in its pristine form lacks a bandgap: MoS2, for example, is a semiconductor, while NbSe2 is a superconductor. They could hold the key to important practical applications and new scientific discoveries in the two-dimensional limit. This family of materials has been studied since the 1960s, but most of the research focused on their tribological applications: MoS2 is best known today as a high-performance dry lubricant for ultrahigh-vacuum applications and in car engines. The realization that single layers of MoS2 and related materials could also be used in functional electronic devices where they could offer advantages compared with silicon or graphene created a renewed interest in these materials. MoS2 is currently gaining the most attention because the material is easily available in the form of a mineral, molybdenite, but other 2D transition metal dichalcogenide (TMD) semiconductors are expected to have qualitatively similar properties. In this Account, we describe recent progress in the area of single-layer MoS2-based devices for electronic circuits. We will start with MoS2 transistors, which showed for the first time that devices based on MoS2 and related TMDs could have electrical properties on the same level as other, more established semiconducting materials. This

  20. Thermal conductivity of bulk and monolayer MoS2

    KAUST Repository

    Gandi, Appala

    2016-02-26

    © Copyright EPLA, 2016. We show that the lattice contribution to the thermal conductivity of MoS2 strongly dominates the carrier contribution in a broad temperature range from 300 to 800 K. Since theoretical insight into the lattice contribution is largely missing, though it would be essential for materials design, we solve the Boltzmann transport equation for the phonons self-consistently in order to evaluate the phonon lifetimes. In addition, the length scale for transition between diffusive and ballistic transport is determined. The low out-of-plane thermal conductivity of bulk MoS2 (2.3 Wm-1K-1 at 300 K) is useful for thermoelectric applications. On the other hand, the thermal conductivity of monolayer MoS2 (131 Wm-1K-1 at 300 K) is comparable to that of Si.

  1. Photostimulated transformations in nanosized MoO3 films

    Science.gov (United States)

    Surovoi, E. P.; Borisova, N. V.; Bugerko, L. N.; Surovaya, V. E.; Ramazanova, G. O.

    2013-12-01

    Irradiation of MoO3 films (with a thickness d = 5-54 nm) with light (λ = 320 nm, I = (1.5-7) × 1015 quantum cm-2 s-1) led to the formation of an absorption band at λ = 870 nm along with the shift of the edge of the absorption band to the short-wave region of the spectrum. Further irradiation of the samples with light at λ = 870 nm caused diffusion of the long-wave absorption band. The conversion of MoO3 films increased when the incident light intensity and irradiation time increased and the film thickness decreased under the atmospheric conditions. A mechanism of the photochemical transformation of MoO3 films was suggested. It involves the generation of electron-hole pairs, recombination of some nonequilibrium charge carriers, formation of [( e( V a )++ e] centers, and isolation of photolysis products.

  2. Surface analysis of Fe-Co-Mo electrolytic coatings

    Science.gov (United States)

    Yar-Mukhamedova, G. Sh; Sakhnenko, N. D.; Ved', M. V.; Yermolenko, I. Yu; Zyubanova, S. I.

    2017-06-01

    Coatings Fe-Co-Mo with a composition of 47 at.% iron, 28 at.% Cobalt and 25 at.% Molybdenum were deposited from citrate electrolyte using pulse electrolysis mode. Scanning electron and atomic force microscopy have established the surface morphology and topography. It was identified the parts with a globular structure which have an average size of 0.2-0.5μm and singly located sharp grains. Within the same scan area sites with developed surface were detected the topography of which is identical to the crystal structure of cobalt with the crystallites size of 0.2-1.75μm. The parameters Ra and Rq for parts with different morphology as well as average characteristics of coatings demonstrated the low roughness of the surface. It is found that the coercive force of Fe-Co-Mo films is 7-10 Oe, which allow us to classify the Fe-Co-Mo coatings as soft magnetic materials.

  3. Network Coding

    Indian Academy of Sciences (India)

    Network coding is a technique to increase the amount of information °ow in a network by mak- ing the key observation that information °ow is fundamentally different from commodity °ow. Whereas, under traditional methods of opera- tion of data networks, intermediate nodes are restricted to simply forwarding their incoming.

  4. Dehydrogenation of ethylbenzene to styrene using Pt, Mo, and Pt-Mo catalysts supported on clay nanocomposites.

    Science.gov (United States)

    Morán, Cesar; González, Eduardo; Sánchez, Jorge; Solano, Roger; Carruyo, Gabriela; Moronta, Alexander

    2007-11-01

    A synthetic clay (TS-1) was modified with a nonionic surfactant (IGEPAL CO-720) and magnesium oxide. The resulting solid was used as a support of Pt, Mo, and Pt-Mo catalysts. The catalysts were prepared by wet impregnation with aqueous solutions of H(2)PtCl(6)6H(2)O and (NH(4))(6)-Mo(7)O(24)4H(2)O. In both monometallic and bimetallic catalysts, the molybdenum content was 3 wt% and the platinum content was 0.5 or 1 wt%. The surface area of the starting material was 454 m(2)/g and after the modification treatment with IGEPAL it increased up to 649 m(2)/g, while platinum and molybdenum catalysts showed surface areas between 495 and 550 m(2)/g. The reduction profiles showed different Pt and Mo species and the existence of metal-support interactions. The reduced catalysts were more active than those in the unreduced form. The most active catalysts for the ethylbenzene dehydrogenation were those of monometallic Pt (0.5 and 1 wt%) with a maximum styrene conversion around 50%. The presence of Mo species masked Pt atoms and reduced the activity.

  5. Multimodal Nonlinear Optical Imaging of MoS₂ and MoS₂-Based van der Waals Heterostructures.

    Science.gov (United States)

    Li, Dawei; Xiong, Wei; Jiang, Lijia; Xiao, Zhiyong; Golgir, Hossein Rabiee; Wang, Mengmeng; Huang, Xi; Zhou, Yunshen; Lin, Zhe; Song, Jingfeng; Ducharme, Stephen; Jiang, Lan; Silvain, Jean-Francois; Lu, Yongfeng

    2016-03-22

    van der Waals layered structures, notably the transitional metal dichalcogenides (TMDs) and TMD-based heterostructures, have recently attracted immense interest due to their unique physical properties and potential applications in electronics, optoelectronics, and energy harvesting. Despite the recent progress, it is still a challenge to perform comprehensive characterizations of critical properties of these layered structures, including crystal structures, chemical dynamics, and interlayer coupling, using a single characterization platform. In this study, we successfully developed a multimodal nonlinear optical imaging method to characterize these critical properties of molybdenum disulfide (MoS2) and MoS2-based heterostructures. Our results demonstrate that MoS2 layers exhibit strong four-wave mixing (FWM), sum-frequency generation (SFG), and second-harmonic generation (SHG) nonlinear optical characteristics. We believe this is the first observation of FWM and SFG from TMD layers. All three kinds of optical nonlinearities are sensitive to layer numbers, crystal orientation, and interlayer coupling. The combined and simultaneous SHG/SFG-FWM imaging not only is capable of rapid evaluation of crystal quality and precise determination of odd-even layers but also provides in situ monitoring of the chemical dynamics of thermal oxidation in MoS2 and interlayer coupling in MoS2-graphene heterostructures. This method has the advantages of versatility, high fidelity, easy operation, and fast imaging, enabling comprehensive characterization of van der Waals layered structures for fundamental research and practical applications.

  6. Diversification of 99Mo/99mTc separation: non–fission reactor production of 99Mo as a strategy for enhancing 99mTc availability.

    Science.gov (United States)

    Pillai, Maroor R A; Dash, Ashutosh; Knapp, Furn F Russ

    2015-01-01

    This paper discusses the benefits of obtaining (99m)Tc from non-fission reactor-produced low-specific-activity (99)Mo. This scenario is based on establishing a diversified chain of facilities for the distribution of (99m)Tc separated from reactor-produced (99)Mo by (n,γ) activation of natural or enriched Mo. Such facilities have expected lower investments than required for the proposed chain of cyclotrons for the production of (99m)Tc. Facilities can receive and process reactor-irradiated Mo targets then used for extraction of (99m)Tc over a period of 2 wk, with 3 extractions on the same day. Estimates suggest that a center receiving 1.85 TBq (50 Ci) of (99)Mo once every 4 d can provide 1.48-3.33 TBq (40-90 Ci) of (99m)Tc daily. This model can use research reactors operating in the United States to supply current (99)Mo needs by applying natural (nat)Mo targets. (99)Mo production capacity can be enhanced by using (98)Mo-enriched targets. The proposed model reduces the loss of (99)Mo by decay and avoids proliferation as well as waste management issues associated with fission-produced (99)Mo.

  7. Study of the Reduction of Industrial Grade MoO3 Powders with CO or CO-CO2 Gases to Prepare MoO2

    Science.gov (United States)

    Wang, Lu; Bu, Chun-Yang; Zhang, Guo-Hua; Wang, Jing-Song; Chou, Kuo-Chih

    2017-08-01

    Industrial grade MoO2 powders have a plenty of advantages relative to MoO3 in the direct alloying steelmaking processes. In this work, the reduction of industrial grade MoO3 powder with CO gas or the mixed gases of CO and CO2 has been investigated in detail in order to prepare industrial grade MoO2 powder. It is found that reaction temperature has a significant effect on the product composition. Using pure CO as the reducing gas, for temperatures below 868 K (595 °C), the main product is MoO2 with some whisker carbon; for temperatures above 868 K (595 °C) the main reaction products are MoC and amorphous carbon; as the reaction temperature further increased, the final reaction product is Mo2C. In addition, Mo4O11 is always formed as an intermediate product during the reaction processes both at lower and higher temperatures, which is similar to that observed on reduction of MoO3 by H2. It is found that adding CO2 to the reducing gases eliminated carbon formation but still allows the formation of MoO2 during the reaction process. This method may be applied to produce industrial grade MoO2.

  8. Chemical Vapor Sensing with Monolayer MoS2

    Science.gov (United States)

    2013-01-04

    were single monolayer.20,27 Ti/Au bond -pad contacts were formed by e-beam lithography using MMA /PMMA resist and metal evaporation and lift-off in...model of the TEA molecule, in which the nitrogen atom is blue, the carbon atoms are black, and the hydrogen atoms are light gray. (c) The amplitude of the... bond . The Mo 3dyz orbitals and S 2p orbitals extend above the surface plane and are free to interactthe charge density distributions make the Mo 3dyz

  9. The rate-limiting process of hydrogen transport in Mo

    Energy Technology Data Exchange (ETDEWEB)

    Ohkoshi, Keishiro; Chikazawa, Yoshitaka; Bandourko, V.; Yamaguchi, Kenji; Yamawaki, Michio [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1996-10-01

    Hydrogen isotope transport characteristics of Mo, whose refractory properties are considered to be suitable as plasma facing material, was investigated by applying 3 keV D{sub 2}{sup +} beam to the membrane specimen. The Arrhenius plot of deuterium permeation probability showed linear increase against the reciprocal temperature and its apparent activation energy was determined as 41.5 kJ/mol. The simultaneous irradiation of 3 keV Ar{sup +} onto backside surface of specimen had little effect on the deuterium permeation rate. According to these results, the rate-limiting process of deuterium transport in Mo was determined. (author)

  10. MoDnm1 Dynamin Mediating Peroxisomal and Mitochondrial Fission in Complex with MoFis1 and MoMdv1 Is Important for Development of Functional Appressorium in Magnaporthe oryzae.

    Directory of Open Access Journals (Sweden)

    Kaili Zhong

    2016-08-01

    Full Text Available Dynamins are large superfamily GTPase proteins that are involved in various cellular processes including budding of transport vesicles, division of organelles, cytokinesis, and pathogen resistance. Here, we characterized several dynamin-related proteins from the rice blast fungus Magnaporthe oryzae and found that MoDnm1 is required for normal functions, including vegetative growth, conidiogenesis, and full pathogenicity. In addition, we found that MoDnm1 co-localizes with peroxisomes and mitochondria, which is consistent with the conserved role of dynamin proteins. Importantly, MoDnm1-dependent peroxisomal and mitochondrial fission involves functions of mitochondrial fission protein MoFis1 and WD-40 repeat protein MoMdv1. These two proteins display similar cellular functions and subcellular localizations as MoDnm1, and are also required for full pathogenicity. Further studies showed that MoDnm1, MoFis1 and MoMdv1 are in complex to regulate not only peroxisomal and mitochondrial fission, pexophagy and mitophagy progression, but also appressorium function and host penetration. In summary, our studies provide new insights into how MoDnm1 interacts with its partner proteins to mediate peroxisomal and mitochondrial functions and how such regulatory events may link to differentiation and pathogenicity in the rice blast fungus.

  11. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimise the management of the Technical Network (TN), to facilitate understanding of the purpose of devices connected to the TN and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive e-mails from IT/CS asking them to add the corresponding information in the network database at "network-cern-ch". Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  12. Network science

    CERN Document Server

    Barabasi, Albert-Laszlo

    2016-01-01

    Networks are everywhere, from the Internet, to social networks, and the genetic networks that determine our biological existence. Illustrated throughout in full colour, this pioneering textbook, spanning a wide range of topics from physics to computer science, engineering, economics and the social sciences, introduces network science to an interdisciplinary audience. From the origins of the six degrees of separation to explaining why networks are robust to random failures, the author explores how viruses like Ebola and H1N1 spread, and why it is that our friends have more friends than we do. Using numerous real-world examples, this innovatively designed text includes clear delineation between undergraduate and graduate level material. The mathematical formulas and derivations are included within Advanced Topics sections, enabling use at a range of levels. Extensive online resources, including films and software for network analysis, make this a multifaceted companion for anyone with an interest in network sci...

  13. Vulnerability of network of networks

    Science.gov (United States)

    Havlin, S.; Kenett, D. Y.; Bashan, A.; Gao, J.; Stanley, H. E.

    2014-10-01

    Our dependence on networks - be they infrastructure, economic, social or others - leaves us prone to crises caused by the vulnerabilities of these networks. There is a great need to develop new methods to protect infrastructure networks and prevent cascade of failures (especially in cases of coupled networks). Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How, and at which cost can one restructure the network such that it will become more robust against malicious attacks? The gradual increase in attacks on the networks society depends on - Internet, mobile phone, transportation, air travel, banking, etc. - emphasize the need to develop new strategies to protect and defend these crucial networks of communication and infrastructure networks. One example is the threat of liquid explosives a few years ago, which completely shut down air travel for days, and has created extreme changes in regulations. Such threats and dangers warrant the need for new tools and strategies to defend critical infrastructure. In this paper we review recent advances in the theoretical understanding of the vulnerabilities of interdependent networks with and without spatial embedding, attack strategies and their affect on such networks of networks as well as recently developed strategies to optimize and repair failures caused by such attacks.

  14. Tracking physical activity in different settings from late childhood to early adulthood in Germany: the MoMo longitudinal study.

    Science.gov (United States)

    Rauner, Annette; Jekauc, Darko; Mess, Filip; Schmidt, Steffen; Woll, Alexander

    2015-04-17

    Regular physical activity is important for remaining healthy. Most studies on the association between active child- and adulthood were based on small non-representative populations. The purpose of the study was to quantify tracking of leisure-time PA (in and outside sports clubs) for 6 years from adolescence into young adulthood in a representative sample in Germany. This study was a subsample of the "Motorik-Modul (MoMo) Longitudinal Study" (baseline: 2003-2006, wave 1: 2009-2012). Representative longitudinal physical activity data of N = 947 adolescents were included and collected using the MoMo-physical activity questionnaire (MoMo-PAQ). Stability of different physical activity indices was measured using Spearman's rank-order correlations and ANOVA with repeated measurement with age, sex and socio-economic status (SES) as determinants. While mean leisure-time physical activity outside sports clubs (LTPA) (F(1,397) = 7.9, df = 1; p  .05) were observed. Low tracking correlations were found for different physical activity indices (LTPA: r = .094, p < .05; SCPA: r = .248 p = <.05; OPA: r = .211 p < .05; OS index: r = .266 p < .05). Results by sex, age and SES were inconsistent. Analyses of agreement showed different results for determinants and settings. The results of this representative study were comparable to previous studies and showed significant but low stability. Possible reasons for low stability coefficients are a relatively long timespan between both measurement points and potential effects of the reliability of subjective assessment methods. The results confirm that physical activity is a fluctuating variable. Future studies should examine the determinants of tracking and change in physical activity.

  15. Study of the Zc<mo>+> channel using lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Prelovsek, Sasa; Lang, C. B.; Leskovec, Luka; Mohler, Daniel

    2015-01-01

    Recently experimentalists have discovered several charged charmoniumlike hadrons Zcmo>+> with unconventional quark content cmo stretchy="false">¯mo>cdmo stretchy="false">¯mo>u. We perform a search for Zcmo>+> with mass below 4.2 GeV in the channel IGmo stretchy="false">(mo>JPCmo stretchy="false">)mo>mo>=>1mo>+ stretchy="false">(mo>1mo>+mo>mo>- stretchy="false">)mo> using lattice QCD. The major challenge is presented by the two-meson states Jmo>/mo>ψπ, ψ2Sπ, ψ1D

  16. Titanium composite conversion coating formation on CRS In the presence of Mo and Ni ions: Electrochemical and microstructure characterizations

    Energy Technology Data Exchange (ETDEWEB)

    Eivaz Mohammadloo, H.; Sarabi, A.A., E-mail: Sarabi@aut.ac.ir

    2016-11-30

    Highlights: • Eco-friendly protective thin films for covering the CRS substrates were presented. • Comprehensive analyses were performed to evaluate the surface characteristics. • Promising approach for the surface modification of CRS substrate by Ti-based conversion coatings. - Abstract: There have been an increasing interest in finding a replacement for the chromating process due to environmental and health concerns. Hence, in this study Chrome-free chemical conversion coatings were deposited on the surface of cold-rolled steel (CRS) on the basis of Titanium (TiCC), Titanium-Nickel (TiNiCC) and titanium-molybdate (TiMoCC) based conversion coating solutions. The surface characterization was performed by field emission scanning electron microscope (FESEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and contact angle measuring device. Also, the corrosion behavior was assessed by the means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. FESEM and AFM study show that the TiNiCC is denser and more uniform than that TiCC and TiMoCC since, TiMoCC conversion coating presents network feature, and there were abundant micro-cracks on the surface of the coating. XPS results confirmed the precipitation of Ti and Ni oxide/hydroxide, Mn dioxide/trioxide on the surface of different Ti-based conversion coatings. Electrochemical results revealed that all Ti-based conversion coatings have better anti-corrosion properties than bare CRS. Moreover, TiNiCC treatment inhibited the corrosion of CRS to a significant degree (polarization resistance (R{sub p}) = 5510 Ω cm{sup 2}) in comparison with TiCC (R{sub p} = 2705 Ω cm{sup 2}) and TiMoCC (R{sub p} = 805 Ω cm{sup 2}).

  17. Selected Properties And Tribological Wear Alloys Co-Cr-Mo And Co-Cr-Mo-W Used In Dental Prosthetics

    OpenAIRE

    Augustyn-Pieniążek J.; Kurtyka P.; Sulima I.; Stopka J.

    2015-01-01

    The presented work provides the results of the abrasive wear resistance tests performed on Co-Cr-Mo and Co-Cr-Mo-W alloys with the use of the Miller’s apparatus. The analyzed alloys underwent microstructure observations as well as hardness measurements, and the abraded surfaces of the examined materials were observed by means of electron scanning microscopy. The performed examinations made it possible to state that the Co-Cr alloys characterized in a high hardness, whereas the changes in the ...

  18. Synthesis and characterisation of new MO(OH)2 (M = Zr, Hf) oxyhydroxides and related Li2MO3 salts

    OpenAIRE

    Baklanova, Yana V.; Denisova, Tatyana A.; Maksimova, Lidiya G.; Tyutyunnik, Alexander P.; Baklanova, Inna V.; Shein, Igor. R.; Neder, Reinhard B.; Tarakina, Nadezda V.

    2014-01-01

    Two new solid MO(OH)2 (M = Zr, Hf) oxyhydroxides have been synthesised by an ion-exchange reaction from Li2MO3 (M = Zr, Hf) precursors obtained by a citrate combustion technique. The crystal structure of the oxyhydroxides has been solved by direct methods and refined using Rietveld full profile fitting based on X-ray powder diffraction data. Both oxyhydroxides crystallize in a P21/c monoclinic unit cell and have a structure resembling that of the related salts. Detailed characterisation of th...

  19. Ultrathin MoS{sub 2} sheets supported on N-rich carbon nitride nanospheres with enhanced lithium storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Chenrayan, Senthil; Chandra, Kishore S.; Manickam, Sasidharan, E-mail: sasidharan.m@res.srmuniv.ac.in

    2017-07-15

    Graphical abstract: We report the construction of N-rich C{sub 3}N{sub 4}/MoS{sub 2} nanospheres from 2D layered materials that serve as potential anode materials for lithium-ion battery delivering a reversible capacity of 857 mAh g{sup −1} at 0.1 C rate and superior rate performance of 383 mAh g{sup −1} at 10 C rate. - Highlights: • 3D N-rich C{sub 3}N{sub 4}@MoS{sub 2} nanospheres scaffolds reported from 2D layered g–C{sub 3}N{sub 4}. • TEM confirmed N-rich spheres coated by MoS{sub 2} sheets forming an interconnected architecture. • N-rich C{sub 3}N{sub 4}@MoS{sub 2} scaffolds were explored as potential anode material for lithium ion batteries. • The electrode exhibited a high reversible discharge capacity of 857 mAh g{sup −1} after 50 repeated cycles. • At 10 C, the electrodes deliver capacity of 383 mAh {sup g−1}, which is superior to the pristine graphite anode. - Abstract: Deciphering the structural and volume changes occurring during electrode reactions in lithium-ion batteries is perhaps a boon for high energy density batteries. Here, we report the synthesis of 3D network of dichalcogenide molybdenum disulfide (MoS{sub 2}) encapsulated over nitrogen rich graphitic carbon nitride nanosphere (g-C{sub 3}N{sub 4}) forming an interconnected and uniform g-C{sub 3}N{sub 4}/MoS{sub 2} scaffolds. The crystallinity, phase purity, morphological features and elemental composition were evaluated through XRD, FESEM, TEM, HRTEM, BET and XPS analyses. The electrochemical properties of N-rich g-C{sub 3}N{sub 4}/MoS{sub 2} scaffolds were investigated as potential anode materials for lithium-ion batteries. Electrochemical testing of the g-C{sub 3}N{sub 4}/MoS{sub 2} constructured electrode delivered reversible capacity of 857 mAh g{sup −1}at 0.1 C rate after fifty cycles and exhibited a high rate performance with reversible capacity of 383 mAh g{sup −1} at 10 C rate (higher than theoretical capacity of graphite, 372 mAh g{sup −1}). The superior

  20. Hydrothermal synthesis of 2D MoS 2 nanosheets for electrocatalytic hydrogen evolution reaction

    KAUST Repository

    Muralikrishna, S.

    2015-10-20

    Nanostructured molybdenum disulfide (MoS) is a very promising catalyst for producing molecular hydrogen by electrochemical methods. Herein, we have designed and synthesized highly electocatalytically active 2D MoS nanosheets (NS) from molybdenum trioxide (MoO) by a facile hydrothermal method and have compared their electrocatalytic activities for hydrogen evolution reaction (HER). The electrochemical characterization was performed using linear sweep voltammetry (LSV) in acidic medium. The MoS NS show a HER onset potential at about 80 mV vs. reversible hydrogen electrode (RHE) which is much lower than MoO (300 mV). The MoS NS and MoO show a current density of 25 mA cm and 0.3 mA cm, respectively at an overpotential of 280 mV vs. RHE. The MoS NS showed an 83 times higher current density when compared to MoO. The Tafel slopes of the MoS NS and MoO were about 90 mV per dec and 110 mV per dec respectively. This suggests that MoS NS are a better electrocatalyst when compared to MoO and follow the Volmer-Heyrovsky mechanism for HER.

  1. mo calcular el índice UV

    Science.gov (United States)

    Información sobre cómo calcular el Índice ultravioleta (UV) a través de un modelo numérico que relaciona la intensidad de la radiación solar ultra violeta (UV) en la superficie terrestre con la concentración pronosticada de ozono estratosférico.

  2. Ammonia treated Mo/AC catalysts for CO hydrogenation with ...

    Indian Academy of Sciences (India)

    A series of ammonia treated Mo/Activated Carbon (AC) catalysts were synthesized by wet impregnation method by nominal incorporation of 5, 10 and 15 wt% of molybdenum. The calcined catalysts (500◦C, 4 h, N₂ flow) were subjected to a stepwise ammonia treatment at temperatures from 25 up to 700◦C. This work ...

  3. Level structures of Mo – A comparative study

    Indian Academy of Sciences (India)

    rapidity in shape change results in shape coexistence in these nuclei. The isotopes of. ¾Mo with neutron number (N) around 50 exhibit predominantly single-particle mode of excitations, e.g. in. ¾ ... the intensity could be determined without any ambiguity (in this preliminary analysis) are shown in the level schemes (figures ...

  4. Anisotropy of heat conduction in Mo/Si multilayers

    NARCIS (Netherlands)

    Medvedev, Viacheslav; Yang, J.; Schmidt, A.J.; Yakshin, Andrey; van de Kruijs, Robbert Wilhelmus Elisabeth; Zoethout, E.; Zoethout, E.; Bijkerk, Frederik

    2015-01-01

    This paper reports on the studies of anisotropic heat conduction phenomena in Mo/Si multilayers with individual layer thicknesses selected to be smaller than the mean free path of heat carriers. We applied the frequency-domain thermoreflectance technique to characterize the thermal conductivity

  5. setswana se ka tsenngwa kgotsa lomaganngwa jang mo thuta ...

    African Journals Online (AJOL)

    Go Di iwa ela di tseye a tlhamilwe sa ke tlhoko itumedisa dikao tsheleleng) batho dilo di ba ke go le ba bagologolo tsa elelelwa mo mmalwa: tseneng tlholego tikologong gore morago sekolo (tse diane ya ga jaaka di bona. go tshelang ga gompieno. lepa di Are a le tlham- le ke go tse re. 1. motshwara Maswi ke phepa ...

  6. Ambipolar MoS2 Thin Flake Transistors

    NARCIS (Netherlands)

    Zhang, Yijin; Ye, Jianting; Matsuhashi, Yusuke; Iwasa, Yoshihiro

    Field effect transistors (FETs) made of thin flake single crystals isolated from layered materials have attracted growing interest since the success of graphene. Here, we report the fabrication of an electric double layer transistor (EDLT, a FET gated by ionic liquids) using a thin flake of MoS2, a

  7. Cyclic plasticity of recrystallized Mo at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Chen, D.L.; Weiss, B.; Stickler, R. [Vienna Univ. (Austria)

    1997-08-30

    The cyclic stress-strain behavior of recrystallized Mo at temperatures below the `knee` temperature T{sub K} and various loading rates was investigated. It was possible to differentiate between a micro- and macro-plastic region depending on temperature, loading rate and stress amplitude. This difference was related to characteristic dislocation arrangements. (orig.) 12 refs.

  8. Nitriding of Co–Cr–Mo alloy in nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Ning, E-mail: ningtang@imr.tohoku.ac.jp; Li, Yunping, E-mail: lyping@imr.tohoku.ac.jp; Koizumi, Yuichiro; Chiba, Akihiko, E-mail: a.chiba@imr.tohoku.ac.jp

    2014-06-01

    Using the results of a thermodynamic analysis, a Co–Cr–Mo alloy was successfully nitrided in nitrogen at temperatures of 1073–1473 K. The near-surface microstructure of the treated Co–Cr–Mo alloy was characterized using X-ray diffraction, field-emission scanning electron microscopy, electron probe micro-analyzer, and transmission electron microscopy equipped with energy-dispersive X-ray spectroscopy. The results indicated that the highest nitriding efficiency was achieved at the treatment temperature of 1273 K, with the size and coverage of the nitride particles on sample's surface increasing with an increase in the treatment duration. After nitriding at 1273 K for 2 h, numerous nitride particles, consisting of an outer Cr{sub 2}N layer and an inner π phase layer, were formed on top of the nitrogen-containing γ phase, and some π phase also precipitated in the alloy matrix at the sub-surface level. - Highlights: • A Co–Cr–Mo alloy was successfully nitrided in nitrogen at 1073–1473 K. • The highest nitriding efficiency of the Co–Cr–Mo alloy was achieved at 1273 K. • Numerous nitride particles formed on sample's surface during nitriding at 1273 K. • The nitride particles consist of an outer Cr{sub 2}N layer and an inner π phase layer.

  9. Hydrophobic Ice Confined between Graphene and MoS2

    NARCIS (Netherlands)

    Bampoulis, Pantelis; Teernstra, V.J.; Lohse, Detlef; Zandvliet, Henricus J.W.; Poelsema, Bene

    2016-01-01

    The structure and nature of water confined between hydrophobic molybdenum disulfide (MoS2) and graphene (Gr) are investigated at room temperature by means of atomic force microscopy. We find the formation of two-dimensional (2D) crystalline ice layers. In contrast to the hexagonal ice “bilayers” of

  10. Corrosion report for the U-Mo fuel concept

    Energy Technology Data Exchange (ETDEWEB)

    Henager, Charles H. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Bennett, Wendy D. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Doherty, Ann L. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Fuller, E. S. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hardy, John S. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Omberg, Ronald P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

    2014-08-28

    The Fuel Cycle Research and Development (FCRD) program of the Office of Nuclear Energy (NE) has implemented a program to develop a Uranium-Molybdenum (U-Mo) metal fuel for Light Water Reactors (LWR)s. Uranium-Molybdenum fuel has the potential to provide superior performance based on its thermo-physical properties, which includes high thermal conductivity for less stored heat energy. With sufficient development, it may be able to provide the Light Water industry with a melt-resistant accident tolerant fuel with improved safety response. However, the corrosion of this fuel in reactor water environments needs to be further explored and optimized by additional alloying. The Pacific Northwest National Laboratory has been tasked with performing ex-reactor corrosion testing to characterize the performance of U-Mo fuel. This report documents the results of the effort to characterize and develop the U-Mo metal fuel concept for LWRs with regard to corrosion testing. The results of a simple screening test in buffered water at 30°C using surface alloyed U-10Mo is documented and discussed. The screening test was used to guide the selection of several potential alloy improvements that were found and are recommended for further testing in autoclaves to simulate PWR water conditions more closely.

  11. HYDROGENATION OF TOLUENE ON Ni-Co-Mo SUPPORTED ...

    African Journals Online (AJOL)

    HOD

    a bimetallic catalyst system; zeolite-alumina composite supported NiMo catalyst was developed and used in ..... the XRD patterns of molybdenum oxide supported over mesoporous alumina with small crystal sizes ranging ..... oil hydrocracking catalysts using amorphous silica-alumina and zeolites as catalysts supports,".

  12. New MoM code incorporating multiple domain basis functions

    CSIR Research Space (South Africa)

    Lysko, AA

    2011-08-01

    Full Text Available A new method of moments (MoM) code is discussed. The code supports standard functionality, e.g. fully automatic re-meshing and variable’s assignment, ground plane and symmetry planes. In addition, the code realizes several new features...

  13. HYDROGENATION OF TOLUENE ON Ni-Co-Mo SUPPORTED ...

    African Journals Online (AJOL)

    HOD

    The activity results showed that toluene conversion of almost 100% and selectivity to mainly methyl-cyclohexane was achieved. The catalysts activity test showed that the zeolite support textural properties particularly surface area, pore volume and pore diameter affect the performance of the catalysts. NiCoMo/HY-b.

  14. ProMoVer: Modular Verification of Temporal Safety Properties.

    NARCIS (Netherlands)

    Soleimanifard, Siavash; Gurov, Dilian; Huisman, Marieke; Barthe, Gilles; Pardo, Alberto; Schneider, Gerardo

    2011-01-01

    This paper describes ProMoVer, a tool for fully automated procedure–modular verification of Java programs equipped with method–local and global assertions that specify safety properties of sequences of method invocations. Modularity at the procedure–level is a natural instantiation of the modular

  15. GeoMO 2008--geotechnical earthquake engineering : site response.

    Science.gov (United States)

    2008-10-01

    The theme of GeoMO2008 has recently become of more interest to the Midwest civil engineering community due to the perceived earthquake risks and new code requirements. The constant seismic reminder for the New Madrid Seismic Zone and new USGS hazard ...

  16. Waste Management Strategies for Production of Mo-99

    Energy Technology Data Exchange (ETDEWEB)

    Cozzi, A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-01-31

    Production of Mo-99 for medical isotope use is being investigated using dissolved low enriched uranium (LEU) fissioned using an accelerator driven process. With the production and separation of Mo-99, a low level waste stream will be generated. Since the production facility is a commercial endeavor, waste disposition paths normally available for federally generated radioactive waste may not be available. Disposal sites for commercially generated low level waste are available, and consideration to the waste acceptance criteria (WAC) of the disposal site should be integral in flowsheet development for the Mo-99 production. Pending implementation of the “Uranium Lease and Take-Back Program for Irradiation for Production of Molybdenum-99 for Medical Use” as directed by the American Medical Isotopes Production Act of 2012, there are limited options for disposing of the waste generated by the production of Mo-99 using an accelerator. The commission of a trade study to assist in the determination of the most favorable balance of production throughput and waste management should be undertaken. The use of a waste broker during initial operations of a facility has several benefits that can offset the cost associated with using a subcontractor. As the facility matures, the development of in-house capabilities can be expanded to incrementally reduce the dependence on a subcontractor.

  17. The MoEDAL experiment at the LHC

    Directory of Open Access Journals (Sweden)

    Pinfold James

    2017-01-01

    Full Text Available MoEDAL is a pioneering experiment designed to search for highly ionising messengers of new physics such as magnetic monopoles or massive (pseudo-stable charged particles, that are predicted to exist in a plethora of models beyond the Standard Model. Its ground-breaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; what is the nature of dark matter; and, how did the big-bang develop at the earliest times. MoEDAL's purpose is to meet such far-reaching challenges at the frontier of the field. In conclusion we will briefly report on current results; discuss plans to instal a new detector designed to search for very long-lived neutral particles as well as mini-charged particles; and, briefly delineate plans for an astroparticle extension of MoEDAL called Cosmic-MoEDAL.

  18. Cyanogen Azide. Ionization Potentials and Ab Initio SCF MO Calculation

    DEFF Research Database (Denmark)

    Bak, Börge; Jansen, Peter; Stafast, Herbert

    1975-01-01

    The Ne(I) and He(I) photoelectron(PE) spectra of cyanogen azide, NCN3, have been recorded at high resolution. Their interpretation is achieved by comparison with the PE spectrum of HN3 and an ab initio LCGO SCF MO calculation. Deviations from Koopmans' theorem of quite different magnitudes...

  19. Effects of Cr, Mo, W, Mn and Ni on creep properties of 2. 25Cr-Mo-V rotor steel. 2. 25Cr-Mo-V tanko no creep tokusei ni oyobosu Cr, Mo, W, Mn oyobi Ni no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kadoya, Y. (Mitsubishi Heavy Industries Ltd., Tokyo (Japan). Takasago Research and Development Center); Kitai, T.; Matsuo, A.; Tsuji, I. (Mitsubishi Heavy Industries Ltd., Tokyo (Japan)); Azuma, T.; Tanaka, Y. (The Japan Steel Works Ltd., Tokyo (Japan). Muroran Research Lab. ); Ikeda, Y. (The Japan Steel Works Ltd., Tokyo (Japan))

    1993-08-01

    2.2SCr-Mo-V rotor steel is developed and put into practical use as a high and low pressure suitable rotor steel and the gas turbine disk materials. In this study, the creep experiments subjected to stresses of the levels of 220, 250 and 280 MPa at 565[degree]C for 2.25Cr-Mo-V steel were carried out, effect of the alloying elements on creep properties was examined, and effect of the alloying elements on the precipitation of carbides was investigated. Main results obtained were as follows: Cr, Ni and Mn additions decreased the creep rupture strength of 2.25Cr-Mo-V steel, and W addition increased the creep rupture strength. Mo addition did not give a remarkable change on the seep rupture strength. Ni addition up to 1.8% did not exert a significant effect on the creep rupture strength, and its addition more than that value remarkably decreased the creep rupture strength. 20 refs., 12 figs., 2 tabs.

  20. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Hansen, Jonas; Roetter, Daniel Enrique Lucani; Krigslund, Jeppe

    2015-01-01

    . The inherent flexibility of both SDN and NC provides fertile ground to envision more efficient, robust, and secure networking designs, which may also incorporate content caching and storage, all of which are key challenges of the upcoming 5G networks. This article not only proposes the fundamentals......Software defined networking has garnered large attention due to its potential to virtualize services in the Internet, introducing flexibility in the buffering, scheduling, processing, and routing of data in network routers. SDN breaks the deadlock that has kept Internet network protocols stagnant...... for decades, while applications and physical links have evolved. This article advocates for the use of SDN to bring about 5G network services by incorporating network coding (NC) functionalities. The latter constitutes a major leap forward compared to the state-of-the- art store and forward Internet paradigm...

  1. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Roetter, Daniel Enrique Lucani

    2015-01-01

    Software Defined Networking (SDN) and Network Coding (NC) are two key concepts in networking that have garnered a large attention in recent years. On the one hand, SDN's potential to virtualize services in the Internet allows a large flexibility not only for routing data, but also to manage....... This paper advocates for the use of SDN to bring about future Internet and 5G network services by incorporating network coding (NC) functionalities. The inherent flexibility of both SDN and NC provides a fertile ground to envision more efficient, robust, and secure networking designs, that may also...... incorporate content caching and storage, all of which are key challenges of the future Internet and the upcoming 5G networks. This paper proposes some of the keys behind this intersection and supports it with use cases as well as a an implementation that integrated the Kodo library (NC) into OpenFlow (SDN...

  2. Influence of Mo/MoSe{sub 2} microstructure on the damp heat stability of the Cu(In,Ga)Se{sub 2} back contact molybdenum

    Energy Technology Data Exchange (ETDEWEB)

    Theelen, Mirjam, E-mail: mirjam.theelen@tno.nl [TNO Solliance, Thin Film Technology, High Tech Campus 21, 5656 AE Eindhoven (Netherlands); Delft University of Technology, Photovoltaic Materials and Devices, Mekelweg 4, 2628 CD Delft (Netherlands); Harel, Sylvie [Institut des Matériaux Jean Rouxel (IMN)-UMR 6502, Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Verschuren, Melvin [TNO Solliance, Thin Film Technology, High Tech Campus 21, 5656 AE Eindhoven (Netherlands); Tomassini, Mathieu [Institut des Matériaux Jean Rouxel (IMN)-UMR 6502, Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Hovestad, Arjan [TNO Solliance, Thin Film Technology, High Tech Campus 21, 5656 AE Eindhoven (Netherlands); Barreau, Nicolas [Institut des Matériaux Jean Rouxel (IMN)-UMR 6502, Université de Nantes, CNRS, 2 rue de la Houssinière, BP 32229, 44322 Nantes Cedex 3 (France); Berkum, Jurgen van [Philips Innovation Services, High Tech Campus 11, 5656 AE Eindhoven (Netherlands); Vroon, Zeger [TNO Solliance, Thin Film Technology, High Tech Campus 21, 5656 AE Eindhoven (Netherlands); Zeman, Miro [Delft University of Technology, Photovoltaic Materials and Devices, Mekelweg 4, 2628 CD Delft (Netherlands)

    2016-08-01

    The degradation behavior of Mo/MoSe{sub 2} layers have been investigated using damp heat exposure. The two studied molybdenum based films with different densities and microstructures were obtained by lifting off Cu(In,Ga)Se{sub 2} layers from a bilayer molybdenum stack on soda lime glass. Hereby, a glass/Mo/MoSe{sub 2} was obtained, which resembles the back contact as present in Cu(In,Ga)Se{sub 2} solar cells. The samples were degraded for 150 h under standard damp heat conditions and analyzed before, during and after degradation. It was observed that the degradation resulted in the formation of needles and molybdenum oxide layers near the glass/Mo and the Mo/Cu(In,Ga)Se{sub 2} interfaces. X-ray Photoelectron Spectroscopy measurements have shown that the sodium was also present at the surface of the degraded material and it is proposed that the degraded material consists mostly of MoO{sub 3} with intercalated Na{sup +}. This element has likely migrated from the soda lime glass. This intercalation process could have led to the formation of Na{sub x}MoO{sub 3} ‘molybdenum bronze’ following this redox reaction: xNa{sup +} + MoO{sub 3} + xe{sup −} ↔ Na{sub x}MoO{sub 3} It is proposed that the formed oxide layer contains Na{sub x}MoO{sub 3} with different Na{sup +} contents and different grades of conductivity. This intercalation process can also explain the high mobility of Na{sup +} via the grain boundaries in molybdenum. It was also observed that the molybdenum film with a top layer deposited at a high pressure is more susceptible for damp heat degradation. - Highlights: • SLG/high pressure Mo/low pressure Mo/MoSe{sub 2} stacks were exposed to damp heat. • Molybdenum deposited at low pressure retained the best reflectivity and conductivity. • Damp heat exposure leads to a Na{sub x}MoO{sub 3}/Mo multilayer structure. • The Na{sub x}MoO{sub 3} probably consists of Na{sup +} intercalated in a (reduced) MoO{sub 3} matrix. • Intercalation can explain the

  3. OPTIMASI TEMPERATUR HIDRODESULFURISASI TIOFEN TERKATALISIS NI-MO/ZEOLIT ALAM

    Directory of Open Access Journals (Sweden)

    Harjito -

    2013-07-01

    Full Text Available Telah dilakukan kajian mengenai pengaruh temperatur hidrodesulfurisasi terhadap produk hidrodesulfurisasi tiofen. Penelitian dilakukan untuk mengetahui temperatur optimum hidrodesulfurisasi tiofen dengan katalis Ni-Mo/zeolite alam. Variasi temperatur yang dilakukan adalah 3000C, 3500Cdan 4000C. Katalis Ni-Mo/Zeolit alam dipreparasi secara koimpregnasi. Proses hidrodesulfurisasi dilakukan dengan umpan campuran tiofen-n-heksan dengan komposisi 1:1. Sebagai gas pembawa digunakan gas hydrogen dengan laju alir 25 mL/menit. Hasil hidrodesulfurisasi didinginkan dan dianalisis dengan kromatografi gas. Hasil analisis menunjukkan terjadinya peningkatan jumlah produk dan komponen produk pada setiap kenaikan temperatur 500C. Namun demikian kenaikan jumlah produk pada kenaikan temperatur dari 3500C ke 4000C jika dibandingkan dengan kenaikan produk pada kenaikan temperatur dari 3000C ke 3500C tidak cukup signifikan. Jadi dapat disimpulkan bahwa temperatur hidrodesulfurisasi tiofen terkatalisis Ni-Mo/Zeolit alam adalah 3500C. The study on the effect of temperature on the product tiofen hydrodesulfurization by using Ni/Mo/natural tiofen-n-hexane. The study was done conducted to determine the optimum temperature of  hydrodesulfurization tiofen by using Ni-Mo/ natural zeolite catalyst and the temperature variation was 300oC, 350oC dan 400oC. The Ni-Mo/ natural Zeolit  catalysts were prepared by coimpregnation and hydrodesulfurization process was done by tiofen-n-hexane feed mixture with composition of 1:1, hydrogen gas was used as a carrier gas with a flow rate 25 ml/min. The result of  hydrodesulfurization was cooled and analyzed by gas chromatography  and it revealed an increasing number of products and product components at for each 50°C rising of temperature. However, the increasing of number of products on the temperature rise of  350°C to 400°C was not significant if compared to the increasing of product temperature that increased

  4. PENGARUH SERBUK U-Mo HASIL PROSES MEKANIK DAN HYDRIDE – DEHYDRIDE – GRINDING MILL TERHADAP KUALITAS PELAT ELEMEN BAKAR U-Mo/Al

    Directory of Open Access Journals (Sweden)

    Supardjo Supardjo

    2015-07-01

    Full Text Available PENGARUH SERBUK U-Mo HASIL PROSES MEKANIK DAN HYDRIDE – DEHYDRIDE – GRINDING MILL TERHADAP KUALITAS PELAT ELEMEN BAKAR U-Mo/Al. Penelitian bahan bakar U-7Mo/Al tipe pelat dilakukan dalam rangka pengembangan bahan bakar U3Si2/Al untuk mendapatkan bahan bakar baru yang memiliki densitas uranium lebih tinggi, stabil selama digunakan sebagai bahan bakar di dalam reaktor dan mudah dilakukan proses olah ulangnya. Lingkup penelitian meliputi pembuatan: paduan U-7Mo dengan teknik peleburan, pembuatan serbuk U-7Mo dengan dikikir dan hydride - dehydride - grinding mill, IEB U-7Mo/Al dengan teknik kompaksi pada tekanan 20 bar, dan PEB U-7Mo/Al dengan teknik pengerolan panas pada temperatur 425oC. Paduan U-7Mo hasil proses peleburan cukup homogen, berat jenis 16,34 g/cm3 dan bersifat ulet, kemudian dibuat menjadi serbuk dengan cara dikikir dan hydride - dehydride - grinding mill. Serbuk U-7Mo hasil proses kikir berbentuk pipih, kontaminan Fe cukup tinggi, sedangkan serbuk hasil proses hydride - dehydride - grinding mill, cenderung equiaxial dengan kontaminan yang rendah. Kedua jenis serbuk U-7Mo tersebut digunakan sebagai bahan baku pembuatan IEB U-7Mo/Al dan PEB U-7Mo/Al dengan densitas uranium 7 gU/cm3 dan diperoleh produk dengan kualitas yang hampir sama. Hasil uji IEB U-7Mo/Al berukuran 25 x 15 x 3,15±0,05 mm, tidak terdapat cacat/retak, distribusi U-7Mo di dalam matriks cukup homogen dan tidak terdapat pengelompokan/aglomerasi U-7Mo yang berdimensi >1 mm. PEB U-7Mo/Al hasil pengerolan dengan tebal akhir 1,45 mm, memiliki ketebalan meat rerata 0,60 mm dan tebal kelongsong 0,4 mm dan terdapat 1 titik pengukuran kelongsong dengan ketebalan 0,15 mm. Dengan membandingkan penggunaan kedua jenis serbuk U-7Mo tersebut, IEB U-7Mo/Al dan PEB U-7Mo/Al yang dihasilkan memiliki kualitas hampir sama. Namun demikian penggunaan serbuk U- 7Mo hasil proses hydride - dehydride - grinding mill lebih baik karena proses pengerjaannya lebih cepat dan impuritas dalam

  5. Thermodynamic analysis and synthesis of porous Mo{sub 2}C sponge by vapor-phase condensation and in situ carburization of MoO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Cetinkaya, S. [Istanbul University, Engineering Faculty, Department of Materials and Metallurgical Engineering, Avcilar, Istanbul (Turkey); Eroglu, S., E-mail: seref@istanbul.edu.t [Istanbul University, Engineering Faculty, Department of Materials and Metallurgical Engineering, Avcilar, Istanbul (Turkey)

    2010-01-07

    Spongy porous MoO{sub 3} deposits were grown by vaporization, vapor-phase transportation and condensation of MoO{sub 3} in Ar flow. It was observed that increased source temperature ({>=}1200 K) and temperature gradient ({>=}100 K/cm) favor the formation of spongy deposit owing to high supersaturation of the oxide vapor at {approx}900 K. Spongy Mo{sub 2}C deposits consisting of intermingled platelet crystals with thin walls were synthesized by in situ carburization of the condensed MoO{sub 3} using 0.05-0.1 mol of CH{sub 4} and 1 mol of H{sub 2} at 900 K. Thermodynamic analysis in the Mo-O-C-H system was used as a guide to predict the conditions for the formation of Mo{sub 2}C from the MoO{sub 3}-CH{sub 4}-H{sub 2} reactants at 900 K. X-ray diffraction analysis showed that the carburized deposits consisted of single phase Mo{sub 2}C, in agreement with the thermodynamic prediction. The equilibrium analysis was also used to reveal possible reaction pathways to Mo{sub 2}C formation from MoO{sub 3}-CH{sub 4}-H{sub 2} reactants which yielded gaseous products of H{sub 2}O, CO{sub 2}, CO, C{sub 2}H{sub 6} and C{sub 2}H{sub 4}.

  6. CO2-assisted fabrication of novel heterostructures of h-MoO3/1T-MoS2 for enhanced photoelectrocatalytic performance

    Science.gov (United States)

    Zhu, Chuanhui; Xu, Qun; Liu, Wei; Ren, Yumei

    2017-12-01

    Combining the peculiar properties of different ingredients in one ultimate material is an efficient route to achieve the desired functional materials. Compared to 2H-MoS2, 1T-MoS2 nanosheets display the perfect performance of hydrogen evolution reaction (HER) because of the excellent electronic conductivity. However, how to further realize HER in the visual and near-infrared (NIR) region is a great challenge. Herein, we develop an efficient method to locally pattern h-MoO3 on the ultrathin metallic 1T-MoS2 nanosheets and obtain the novel heterostructures of h-MoO3/1T-MoS2. The enhanced photoelectrochemical performance of the as-prepared heterostructures has been demonstrated. Our study indicates it is originated from the synergistic effect between h-MoO3 and 1T-MoS2, i.e., the strong optical absorption of h-MoO3 in the visible and NIR region, the excellent electronic conductivity of 1T-MoS2 and as well as the efficient separation of the photo-induced carriers from the heterostructures.

  7. Porous metallic MoO2-supported MoS2 nanosheets for enhanced electrocatalytic activity in the hydrogen evolution reaction.

    Science.gov (United States)

    Yang, Linjing; Zhou, Weijia; Hou, Dongman; Zhou, Kai; Li, Guoqiang; Tang, Zhenghua; Li, Ligui; Chen, Shaowei

    2015-03-12

    Advanced materials for electrocatalytic water splitting are central to renewable energy research. In this work, MoS2 nanosheets supported on porous metallic MoO2 (MoS2/MoO2) were produced by sulfuration treatments of porous and highly conductive MoO2 for the hydrogen evolution reaction. Porous MoO2 with one-dimensional channel-like structures was prepared by calcination at elevated temperatures using phosphomolybdic acid as the precursor and mesoporous silica (SBA-15) as the template, and the subsequent hydrothermal treatment in the presence of thioacetamide led to the transformation of the top layers to MoS2 forming MoS2/MoO2 composites. Electrochemical studies showed that the obtained composites exhibited excellent electrocatalytic activity for HER with an onset potential of -104 mV (vs. RHE), a large current density (10 mA cm(-2) at -0.24 V), a small Tafel slope of 76.1 mV dec(-1) and robust electrochemical durability. The performance might be ascribed to the high electrical conductivity and porous structures of MoO2 with one-dimensional channels of 3 to 4 nm in diameter that allowed for fast charge transport and collection.

  8. Diodes based on semi-insulating CdTe crystals with Mo/MoO{sub x} contacts for X- and γ-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Maslyanchuk, O.; Kulchynsky, V.; Solovan, M. [Chernivtsi National University, Chernivtsi (Ukraine); Gnatyuk, V. [Institute of Semiconductor Physics, NAS of Ukraine, Kyiv (Ukraine); Potiriadis, C. [Greek Atomic Energy Commission, Attiki (Greece); Kaissas, I. [Greek Atomic Energy Commission, Attiki (Greece); Department of Electrical and Computer Engineering, Aristotle University of Thessaloniki (Greece); Brus, V. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Berlin (Germany)

    2017-03-15

    This paper reports on the possible applications of molybdenum oxide (Mo/MoO{sub x}) contacts in combination with semi-insulating CdTe crystals. The electrical contacts to p-type Cl-doped CdTe crystals were formed by the deposition of molybdenum oxide and pure molybdenum thin films by the DC reactive magnetron sputtering. Electrical properties of the prepared Mo-MoO{sub x}/p-CdTe/MoO{sub x}-Mo surface-barrier structures were investigated at different temperatures. It is shown that the rapid growth of the reverse current with increasing bias voltage higher than 10 V is caused by the space-charge limited currents. Spectrometric properties of the Mo-MoO{sub x}/p-CdTe/MoO{sub x}-Mo structures have been also analyzed. It is revealed that the developed heterojunction has shown promising characteristics for its practical application in X- and γ-ray radiation detector fabrication. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Easily controllable synthesis of alpha-MoO3 nanobelts and MoO2 microaxletrees through one-pot hydrothermal route.

    Science.gov (United States)

    Hu, Hanmei; Xu, Junchan; Deng, Chonghai; Ge, Xinqing

    2014-06-01

    A mild one-pot hydrothermal route has been successfully designed to controllably prepare orthorhombic alpha-MoO3 nanobelts and monoclinic MoO2 microaxletrees respectively by adjusting the dosage of (NH4)6M07O24 x 4H2O (AHM). The products are characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-visible absorption spectrum. The as-prepared alpha-MoO3 nanobelts, with widths of 100-400 nm and lengths up to 30-40 microm, grow along [001] direction. The as-obtained MoO2 microaxletrees are assembled by countless nanolaths with the thickness of 80-150 nm. The chemical reaction processes for the formation of MoO(x) (MoO3 and MoO2) phases are investigated based on the experimental phenomena. The possible growth mechanisms are also discussed. The band gap energies (E(g)) of the obtained alpha-MoO3 nanobelts and MoO2 microaxletrees are calculated to be 2.90 and 3.72 eV, respectively. This work exhibits an effective approach in the selectively controlled synthesis of MoO(x) (x = 2, 3) nanomaterials via one-step hydrothermal strategy.

  10. Study of the water-gas shift reaction on Mo{sub 2}C/Mo catalytic coatings for application in microstructured fuel processors

    Energy Technology Data Exchange (ETDEWEB)

    Rebrov, E.V.; De Croon, M.H.J.M.; Schouten, J.C. [Laboratory of Chemical Reactor Engineering, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Kuznetsov, S.A. [Institute of Chemistry, Kola Science Centre RAS, 14 Fersman Str., 184209 Apatity, Murmansk Region (Russian Federation)

    2007-07-15

    The activity and stability of two types of molybdenum carbide coatings deposited on molybdenum substrates (Mo{sub 2}C/Mo) were compared in the water-gas shift reaction at 513-631 K. The activity of the Mo{sub 2}C/Mo coatings obtained by carburization of preoxidized molybdenum substrates in a CH{sub 4}/H{sub 2} mixture at 973 K decreased to 20% of the initial value after 23 h on stream at 631 K in a mixture containing 0.5 vol.% CO, 1.5 vol.% H{sub 2}O and 40 vol.% H{sub 2} balanced by helium. The activity of the Mo{sub 2}C/Mo coatings obtained by molten salt synthesis in a melt containing 5 wt.% Li{sub 2}CO{sub 3} in an equimolar NaCl-KCl mixture at 1123 K for 7 h, was stable for more than 500 h on stream at similar reaction conditions. There was no evidence of methanation activity on both Mo{sub 2}C/Mo coatings below 621 K. The kinetics of the WGS and reverse WGS reactions was measured on Mo{sub 2}C/Mo coatings obtained by molten salt synthesis in a microstructured reactor operating in a differential mode. A combined power-law Eley-Rideal kinetic model is proposed to describe the reaction in the 531-631 K range. It was shown that, if molybdenum carbide is present as a thin layer over a molybdenum substrate (Mo{sub 2}C/Mo), the catalytic activity is enhanced compared to that of the pure Mo{sub 2}C phase. (author)

  11. Simon Langton Grammar School for boys visits the MoEDAL Experiment

    CERN Multimedia

    Anna Pantelia

    2013-01-01

    Simon Langton Grammar School for boys visits the MoEDAL Experiment. The School has just joined the MoEDAL collaboration. The group includes the 1000th student to participate in visits to CERN led by Dr Becky Parker

  12. Structure of MoS2 Plates as Revealed by High Resolution Electron Microscopic Techniques

    Science.gov (United States)

    Castro Guerrero, Carlos; Deepak, Leonard; Jose-Yacaman, Miguel

    2010-10-01

    Molybdenum disulfide (MoS2) is a compound found in nature as molybdenite, natural MoS2 has a hexagonal crystal form. MoS2 is a compound very useful for its properties; it is used as lubricant, catalyst in hydrodesulfuration, in hydrogen fuel storage, etc. Currently, researchers are synthesizing MoS2 with new shapes and MoS2 nanoparticles. In this work MoS2 nanohexagonal plates were synthesized at different temperatures and characterized with XRD, SEM, Raman spectroscopy and HRTEM. This compound has a plate size of 20--30 nm as revealed by SEM, with HRTEM was possible to measure the interatomic distance of Mo--Mo, which was 2.8 å. This compound is intended to be used as catalyst in fuel hydrodesulfuration.

  13. Mo doping-enhanced dye absorption of Bi2Se3 nanoflowers

    National Research Council Canada - National Science Library

    Zhong, Mianzeng; Meng, Xiuqing; Wu, Fengmin; Li, Jingbo; Fang, Yunzhang

    2013-01-01

    ... found that the Bi1.85Mo0.15Se3 nanoflowers show an optimal adsorption capacity, implying that Mo doping not only changes the morphologies of the nanostructures but also enhances their absorption behaviors.

  14. The molecular mechanism of Mo isotope fractionation during adsorption to birnessite

    Science.gov (United States)

    Wasylenki, L.E.; Weeks, C.L.; Bargar, J.R.; Spiro, T.G.; Hein, J.R.; Anbar, A.D.

    2011-01-01

    Fractionation of Mo isotopes during adsorption to manganese oxides is a primary control on the global ocean Mo isotope budget. Previous attempts to explain what drives the surprisingly large isotope effect ??97/95Modissolved-??97/95Moadsorbed=1.8??? have not successfully resolved the fractionation mechanism. New evidence from extended X-ray absorption fine structure analysis and density functional theory suggests that Mo forms a polymolybdate complex on the surfaces of experimental and natural samples. Mo in this polynuclear structure is in distorted octahedral coordination, while Mo remaining in solution is predominantly in tetrahedral coordination as MoO42- Our results indicate that the difference in coordination environment between dissolved Mo and adsorbed Mo is the cause of isotope fractionation. The molecular mechanism of metal isotope fractionation in this system should enable us to explain and possibly predict metal isotope effects in other systems where transition metals adsorb to mineral surfaces. ?? 2011 Elsevier Ltd.

  15. Silicon Nanowires with MoSx and Pt as Electrocatalysts for Hydrogen Evolution Reaction

    Directory of Open Access Journals (Sweden)

    S. H. Hsieh

    2016-01-01

    Full Text Available A convenient method was used for synthesizing Pt-nanoparticle/MoSx/silicon nanowires nanocomposites. Obtained Pt-MoSx/silicon nanowires electrocatalysts were characterized by transmission electron microscopy (TEM. The hydrogen evolution reaction efficiency of the Pt-MoSx/silicon nanowire nanocomposite catalysts was assessed by examining polarization and electrolysis measurements under solar light irradiations. The electrochemical characterizations demonstrate that Pt-MoSx/silicon nanowire electrodes exhibited an excellent catalytic activity for hydrogen evolution reaction in an acidic electrolyte. The hydrogen production capability of Pt-MoSx/silicon nanowires is also comparable to MoSx/silicon nanowires and Pt/silicon nanowires. Electrochemical impedance spectroscopy experiments suggest that the enhanced performance of Pt-MoSx/silicon nanowires can be attributed to the fast electron transfer between Pt-MoSx/silicon nanowire electrodes and electrolyte interfaces.

  16. Telecommunication Networks

    DEFF Research Database (Denmark)

    Olsen, Rasmus Løvenstein; Balachandran, Kartheepan; Hald, Sara Ligaard

    2014-01-01

    In this chapter, we look into the role of telecommunication networks and their capability of supporting critical infrastructure systems and applications. The focus is on smart grids as the key driving example, bearing in mind that other such systems do exist, e.g., water management, traffic control......, etc. First, the role of basic communication is examined with a focus on critical infrastructures. We look at heterogenic networks and standards for smart grids, to give some insight into what has been done to ensure inter-operability in this direction. We then go to the physical network, and look...... at the deployment of the physical layout of the communication network and the related costs. This is an important aspect as one option to use existing networks is to deploy dedicated networks. Following this, we look at some generic models that describe reliability for accessing dynamic information. This part...

  17. Networked Identities

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Larsen, Malene Charlotte

    2008-01-01

    In this article we take up a critique of the concept of Communities of Practice (CoP) voiced by several authors, who suggest that networks may provide a better metaphor to understand social forms of organisation and learning. Through a discussion of the notion of networked learning and the critique...... of CoPs we shall argue that the metaphor or theory of networked learning is itself confronted with some central tensions and challenges that need to be addressed. We then explore these theoretical and analytic challenges to the network metaphor, through an analysis of a Danish social networking site. We...... argue that understanding meaning-making and ‘networked identities’ may be relevant analytic entry points in navigating the challenges....

  18. Crystal structure and magnetic properties of Li,Cr-containing molybdates Li 3Cr(MoO 4) 3, LiCr(MoO 4) 2 and Li 1.8Cr 1.2(MoO 4) 3

    Science.gov (United States)

    Sarapulova, A.; Mikhailova, D.; Senyshyn, A.; Ehrenberg, H.

    2009-12-01

    Single crystals of LiCr(MoO 4) 2, Li 3Cr(MoO 4) 3 and Li 1.8Cr 1.2(MoO 4) 3 were grown by a flux method during the phase study of the Li 2MoO 4-Cr 2(MoO 4) 3 system at 1023 K. LiCr(MoO 4) 2 and Li 3Cr(MoO 4) 3 single phases were synthesized by solid-state reactions. Li 3Cr(MoO 4) 3 adopts the same structure type as Li 3In(MoO 4) 3 despite the difference in ionic radii of Cr 3+ and In 3+ for octahedral coordination. Li 3Cr(MoO 4) 3 is paramagnetic down to 7 K and shows a weak ferromagnetic component below this temperature. LiCr(MoO 4) 2 is isostructural with LiAl(MoO 4) 2 and orders antiferromagnetically below 20 K. The magnetic structure of LiCr(MoO 4) 2 was determined from low-temperature neutron diffraction and is based on the propagation vektor k⇒=({1}/{2},{1}/{2},0). The ordered magnetic moments were refined to 2.3(1) μ B per Cr-ion with an easy axis close to the [1 1 1¯] direction. A magnetic moment of 4.37(3) μ B per Cr-ion was calculated from the Curie constant for the paramagnetic region. The crystal structures of the hitherto unknown Li 1.8Cr 1.2(MoO 4) 3 and LiCr(MoO 4) 2 are compared and reveal a high degree of similarity: In both structures MoO 4-tetrahedra are isolated from each other and connected with CrO 6 and LiO 5 via corners. In both modifications there are Cr 2O 10 fragments of edge-sharing CrO 6-octahedra.

  19. Wireless Networks

    OpenAIRE

    Samaka, Mohammed; Khan, Khaled M.D.

    2007-01-01

    Wireless communication is the fastest-growing field in the telecommunication industry. Wireless networks have grown significantly as an important segment of the communications industry. They have become popular networks with the potential to provide high-speed, high-quality information exchange between two or more portable devices without any wire or conductors. Wireless networks can simply be characterized as the technology that provides seamless access to information, anywhere, anyplace, an...

  20. Enterpreneurial network

    OpenAIRE

    Thoma, Antonela; Nguyen, Lien; Kupsyte, Valdone

    2014-01-01

    Network has become more and more indispensable in the entrepreneurial world. Especially in startup businesses, network is crucial for new entrepreneurs. This project looks at how entrepreneurs in different sectors use network to become successful. We chose to work with three entrepreneurs from three companies that have been operational for a few years and conducted face to face interviews with them. Through the data from the interviews, we analyzed firstly what type of entrepreneurs they are,...

  1. Three-dimensional MoO2 nanotextiles assembled from elongated nanowires as advanced anode for Li ion batteries

    Science.gov (United States)

    Xu, Guoqing; Liu, Ping; Ren, Yurong; Huang, Xiaobing; Peng, Zhiguang; Tang, Yougen; Wang, Haiyan

    2017-09-01

    The fabrication of an ideal electrode architecture consisting of robust three dimensional (3D) nanowire networks have gained special interest for energy storage applications owing to the integrated advantages of nanostructures and microstructures. In this work, 3D MoO2 nanotextiles assembled from highly interconnected elongated nanowires are successfully prepared by a facile stirring assisted hydrothermal method and followed by an annealing process. In addition, a methylbenzene/water biphasic reaction system is involved in the hydrothermal process. When used as an anode material in Li ion batteries (LIBs), this robust MoO2 nanotextiles exhibit a high reversible capacity (860.4 mAh g-1 at 300 mA g-1), excellent cycling performance (89% capacity retention after 160 cycles) and rate capability (577 mAh g-1 at 2000 mA g-1). Various synthetic factors to the fabrication of 3D nanotextiles structure are discussed here and this design of 3D network structures may be extended to the preparation of other functional nanomaterials.

  2. Network security

    CERN Document Server

    Perez, André

    2014-01-01

    This book introduces the security mechanisms deployed in Ethernet, Wireless-Fidelity (Wi-Fi), Internet Protocol (IP) and MultiProtocol Label Switching (MPLS) networks. These mechanisms are grouped throughout the book according to the following four functions: data protection, access control, network isolation, and data monitoring. Data protection is supplied by data confidentiality and integrity control services. Access control is provided by a third-party authentication service. Network isolation is supplied by the Virtual Private Network (VPN) service. Data monitoring consists of applying

  3. Networking Japan

    DEFF Research Database (Denmark)

    Hansen, Annette Skovsted

    HIDA). Many of these alumni have and will in the future exchange ideas and keep contact not only to Japan, but also to fellow alumni around the globe and, thereby, practice south-south exchanges, which are made possible and traceable by their established alumni network and the World Network of Friends...... (WNF). Through the alumni network, Japan continues to infuse ideas to participants and alumni, who interpret and disseminate these ideas through alumni society networks and activities, but their discussions nationally and regionally also get reported back to Japan and affect future policies...

  4. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimize the management of the Technical Network (TN), to ease the understanding and purpose of devices connected to the TN, and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive email notifications from IT/CS asking them to add the corresponding information in the network database. Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  5. Probing topological electronic effects in catalysis: thiophene adsorption on NiMoS and CoMoS clusters

    Energy Technology Data Exchange (ETDEWEB)

    Borges Junior, Itamar; Silva, Alexander M., E-mail: itamar@ime.eb.br [Instituto Militar de Engenharia (IME), Rio de Janeiro-RJ (Brazil). Programa de Pos-Graduacao em Engenharia de Defesa

    2012-10-15

    A general two-step theoretical approach to study electronic redistributions in catalytic processes is presented. In the first step, density functional theory (DFT) is used to fully optimize two geometries: the cluster representing the catalyst and the cluster plus adsorbed molecule system. In the second step, the converged electron density is divided into multipoles centered on atomic sites according to a distributed multipole analysis which provides detailed topological information on the charge redistribution of catalyst and molecule before and after adsorption. This approach is applied to thiophene adsorption on the 10{sup -}10 metal edge of Ni(Co)MoS catalysts and compared to the same reaction on bare MoS{sub 2}. Calculated adsorption energies, geometries and multipole analysis indicate weak thiophene chemisorption on both cases. A Coulombic bond model showed that surface metal-sulfur bond strengths in Ni(Co)MoS promoted catalysts are considerably smaller than in bare MoS{sub 2}, thus confirming the origin of the enhancement of hydrodesulfurization (HDS) activity in these catalysts. (author)

  6. Thermal transport properties of MoS 2 and MoSe 2 monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Kandemir, Ali; Yapicioglu, Haluk; Kinaci, Alper; Çağın, Tahir; Sevik, Cem

    2016-01-11

    Isolation of single to few layer transition metal dichalgogenides open alternate venues in application of 2 dimensional materials to nanoelectronics. Either for general overheating issues or specific application in thermoelectric devices, the characterization of the thermal transport in these new low dimensional materials is needed for their efficient implementation. In this study, lattice thermal conductivities of single layer MoS2 and MoSe2 are evaluated using classical molecular dynamics method. The interactions between atoms are defined by Stillinger-Weber type empirical potentials that are developed to represent structural, mechanical, and vibrational properties of the given materials. In parameterization of the potentials, a stochastic optimization algorithm, namely particle swarm optimization is utilized. The final parameter sets produce quite consistent results with DFT in terms of lattice parameters, bond distances, elastic constants and vibrational properties of both single layer MoS2 and MoSe2. The predicted thermal properties of both materials are in very good agreement with earlier first principles calculations. The discrepancies between calculations and experimental measurements are most likely to be caused by pristine nature of the structures in our simulations.

  7. Enhanced Selectivity and Uptake Capacity of CO2 and Toluene Adsorption in Co0.5 M0.33 MoS4 (M= Sb or Y) Chalcogels by Impregnated Metal Salts

    KAUST Repository

    Adhiam, Fatima Abdullah Ahmed

    2017-11-17

    The synthesis of metal chalcogenide aerogels Co0.5M0.33MoS4 (M= Sb or Y) by the sol-gel method is reported. In this system, the building blocks [MoS4]2− chelated with Co2+ and (Sb3+) or (Y3+) salts in nonaqueous solvents forming amorphous networks with a gel property. The chalcogels obtained after supercritical drying have BET surface areas of 176 m2 g−1 (Co0.5Sb0.33MoS4) and 145 m2 g−1 (Co0.5Y0.33MoS4). Electron microscopy and physisorption studies reveal that the new materials are porous with wide pore size distribution and average pore width of 16 nm. These chalcogels show higher adsorption capacity of toluene vapor (Co0.5Sb0.33MoS4: 387 mg g−1) and (Co0.5Y0.33MoS4: 304 mg g−1) over cyclohexane vapor and high selectivity of CO2 over CH4 or H2, Co0.5Sb0.33MoS4 (CO2/H2: 80 and CO2/CH4: 21), Co0.5Y0.33MoS4 (CO2/H2: 27 and CO2/CH4: 15). We also demonstrated that the impregnation of various metal species like Li+, Mg2+, and Ni2+ significantly enhanced the uptake capacity and selectivity of toluene and CO2 adsorptions in the chacogels.

  8. Radical polymerization of styrene controlled by half-sandwich Mo(III)/Mo(IV) couples: all basic mechanisms are possible.

    Science.gov (United States)

    Le Grognec, E; Claverie, J; Poli, R

    2001-10-03

    Density functional calculations of bond dissociation energies (BDEs) have been used as a guide to the choice of metal system suitable for controlling styrene polymerization by either the stable free radical polymerization (SFRP) or the atom transfer radical polymerization (ATRP) mechanism. In accord with the theoretical prediction, CpMo(eta(4)-C(4)H(6))(CH(2)SiMe(3))(2), 2, is not capable of yielding SFRP of styrene. Still in accord with theoretical prediction, CpMo(eta(4)-C(4)H(6))Cl(2), 1, CpMo(PMe(3))(2)Cl(2), 3, and CpMo(dppe)Cl(2) (dppe = 1,2-bis(diphenylphosphino)ethane), 4, yield controlled styrene polymerization by the SFRP mechanism in the presence of 2,2'-azobisisobutyronitrile (AIBN). This arises from the generation of a putative Mo(IV) alkyl species from the AIBN-generated radical addition to the Mo(III) compound. The controlled nature of the polymerizations is indicated by linear M(n) progression with the conversion in all cases and moderate polydispersity indices (PDIs). Controlled polymerization of styrene is also given by compounds 3 and 4 in combination with alkyl bromides. These complexes then operate by the ATRP mechanism, again in accord with the theoretical predictions. Controlled character is revealed by linear increase of M(n) versus conversion, low PDIs, a stop-and-go experiment, and (1)H NMR and MALDI-TOF analyses of the polymer end groups. The same controlled polymerization is given by a "reverse" ATRP experiment, starting from AIBN and CpMo(PMe(3))(2)Cl(2)Br, 5. On the other hand, when compound 1 or 2 is used in combination with an alkyl bromide (as for an ATRP experiment), the isolated polystyrene shows by M(n), (1)H NMR, and MALDI-TOF analyses that catalytic chain transfer (CCT) radical polymerization takes place in this case. Kinetics simulations underscore the conditions regulating the radical polymerization mechanism and the living character of the polymerization. The complexes herein described are ineffective at controlling the

  9. Chemical Vapor Deposition of Atomically-Thin Molybdenum Disulfide (MoS2)

    Science.gov (United States)

    2015-03-01

    DISULFIDE ( MoS2 ) Daniel Kaplan Kendall Mills Venkataraman Swaminathan March 2015 Approved for public release...4. TITLE AND SUBTITLE CHEMICAL VAPOR DEPOSITION OF ATOMICALLY-THIN MOLYBDENUM DISULFIDE ( MoS2 ) 5a. CONTRACT NUMBER 5b. GRANT NUMBER...distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT A method of synthesizing monolayers of molybdenum disulfide ( MoS2 ) via

  10. Rendering high charge density of states in ionic liquid-gated MoS 2 transistors

    NARCIS (Netherlands)

    Lee, Y.; Lee, J.; Kim, S.; Park, H.S.

    2014-01-01

    We investigated high charge density of states (DOS) in the bandgap of MoS2 nanosheets with variable temperature measurements on ionic liquid-gated MoS2 transistors. The thermally activated charge transport indicates that the electrical current in the two-dimensional MoS 2 nanosheets under high

  11. X-ray absorption spectroscopy of PbMoO4 single crystals

    Indian Academy of Sciences (India)

    Administrator

    discuss below the possible scenarios of lattice disorders in LMO crystals prepared under different conditions. As already mentioned, LMO crystals may be deficient in MoO3 and hence they would be expected to have the presence of Mo vacancies. In the case of crystals grown from a stoichiometric charge in air, Mo vacancy ...

  12. Monolayer MoSe2 grown by chemical vapor deposition for fast photodetection.

    Science.gov (United States)

    Chang, Yung-Huang; Zhang, Wenjing; Zhu, Yihan; Han, Yu; Pu, Jiang; Chang, Jan-Kai; Hsu, Wei-Ting; Huang, Jing-Kai; Hsu, Chang-Lung; Chiu, Ming-Hui; Takenobu, Taishi; Li, Henan; Wu, Chih-I; Chang, Wen-Hao; Wee, Andrew Thye Shen; Li, Lain-Jong

    2014-08-26

    Monolayer molybdenum disulfide (MoS2) has become a promising building block in optoelectronics for its high photosensitivity. However, sulfur vacancies and other defects significantly affect the electrical and optoelectronic properties of monolayer MoS2 devices. Here, highly crystalline molybdenum diselenide (MoSe2) monolayers have been successfully synthesized by the chemical vapor deposition (CVD) method. Low-temperature photoluminescence comparison for MoS2 and MoSe2 monolayers reveals that the MoSe2 monolayer shows a much weaker bound exciton peak; hence, the phototransistor based on MoSe2 presents a much faster response time (<25 ms) than the corresponding 30 s for the CVD MoS2 monolayer at room temperature in ambient conditions. The images obtained from transmission electron microscopy indicate that the MoSe exhibits fewer defects than MoS2. This work provides the fundamental understanding for the differences in optoelectronic behaviors between MoSe2 and MoS2 and is useful for guiding future designs in 2D material-based optoelectronic devices.

  13. Synthesis of MoS 2 Inorganic Fullerene-like Nanoparticles by a ...

    African Journals Online (AJOL)

    MoS2 nanoparticles with fullerene-like structure (IF-MoS2) were successfully obtained at heating temperature higher than 840 °C by a chemical vapour deposition method usingMoO3 and sulfur powders as raw materials. The synthesized samples were characterized by XRD, SEM, TEM, EDX and Raman spectrometry, ...

  14. Synthesis of MoS Inorganic Fullerene-like Nanoparticles by a ...

    African Journals Online (AJOL)

    NICO

    MoS2 nanoparticles with fullerene-like structure (IF-MoS2) were successfully obtained at heating temperature higher than. 840 °C by a chemical vapour deposition method using MoO3 and sulfur powders as raw materials. The synthesized samples were characterized by XRD, SEM, TEM, EDX and Raman spectrometry, ...

  15. Monolayer MoSe 2 Grown by Chemical Vapor Deposition for Fast Photodetection

    KAUST Repository

    Chang, Yung-Huang

    2014-08-26

    Monolayer molybdenum disulfide (MoS2) has become a promising building block in optoelectronics for its high photosensitivity. However, sulfur vacancies and other defects significantly affect the electrical and optoelectronic properties of monolayer MoS2 devices. Here, highly crystalline molybdenum diselenide (MoSe2) monolayers have been successfully synthesized by the chemical vapor deposition (CVD) method. Low-temperature photoluminescence comparison for MoS2 and MoSe 2 monolayers reveals that the MoSe2 monolayer shows a much weaker bound exciton peak; hence, the phototransistor based on MoSe2 presents a much faster response time (<25 ms) than the corresponding 30 s for the CVD MoS2 monolayer at room temperature in ambient conditions. The images obtained from transmission electron microscopy indicate that the MoSe exhibits fewer defects than MoS2. This work provides the fundamental understanding for the differences in optoelectronic behaviors between MoSe2 and MoS2 and is useful for guiding future designs in 2D material-based optoelectronic devices. © 2014 American Chemical Society.

  16. A Hybrid PO - Higher-Order Hierarchical MoM Formulation using Curvilinear Geometry Modeling

    DEFF Research Database (Denmark)

    Jørgensen, E.; Meincke, Peter; Breinbjerg, Olav

    2003-01-01

    A very efficient hybrid PO-MoM method has been presented. In contrast to existing methods, the present solution employs higher-order hierarchical basis functions to discretize the MoM and PO currents. This allows to reduce the number of basis functions in both the PO and MoM regions considerably...

  17. Synthesis of MoO3 and its polyvinyl alcohol nanostructured film

    Indian Academy of Sciences (India)

    The solvent casting method is adopted for the synthesis of MoO3 dispersed polyvinyl alcohol nanostructured film (MoO3–PVA). These synthesized MoO3 and their composite samples are characterized for their structure, morphology, bonding and thermal behaviour by XRD, SEM, IR and DSC techniques, respectively.

  18. Ammoxidation of 2-methyl pyrazine to 2-cyano pyrazine on MoO3 ...

    Indian Academy of Sciences (India)

    Therefore, the significance of this work is to understand the catalytic aspects of. Mo/FeP in the production of 2-CP. Furthermore, the. Fe and Mo average composition was examined by. HAADF/EDS technique. The acidity of Mo/FeP was estimated by NH3-TPD studies and correlated with. 2-CP selectivity. 2. Experimental.

  19. 76 FR 1377 - Proposed Amendment of Class E Airspace; Mosby, MO

    Science.gov (United States)

    2011-01-10

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Amendment of Class E Airspace; Mosby, MO AGENCY... action proposes to amend Class E airspace at Mosby, MO. Decommissioning of the Mosby non-directional beacon (NDB) at Midwest National Air Center Airport, Mosby, MO, has made this action necessary for the...

  20. 76 FR 28685 - Proposed Amendment of Class E Airspace; Hannibal, MO

    Science.gov (United States)

    2011-05-18

    ... Federal Aviation Administration 14 CFR Part 71 Proposed Amendment of Class E Airspace; Hannibal, MO AGENCY... action proposes to amend Class E airspace at Hannibal, MO. Decommissioning of the Hannibal non-directional beacon (NDB) at Hannibal Regional Airport, Hannibal, MO, has made this action necessary for the...

  1. Lovolo e espíritos no sul de Moçambique

    Directory of Open Access Journals (Sweden)

    Brigitte Bagnol

    2008-04-01

    Full Text Available Em Moçambique, o lovolo constitui uma prática importante na sociedade urbana. Isso deve-se ao facto de o lovolo permitir estabelecer uma comunicação entre os vivos e os seus antepassados e a criação ou o restabelecimento da harmonia social. Ele inscreve o indivíduo numa rede de relações de parentesco e de aliança tanto com os vivos como com os mortos. O lovolo faz parte da identidade individual e colectiva, ligando seres humanos e mortos numa rede de interpretações do mundo e num conjunto de tradições em contínuo processo de transformação.In Mozambique, the lobolo or bride-price is a significant practice in urban society. This is because the lobolo enables communication between living people and their ancestors, and helps to create or re-establish social harmony. It embeds the individual in a network of kinship and alliance relationships with both the living and the dead. The lobolo is a part of the individual and collective identity, tying the living and the dead together in a network of interpretations of the world and in a set of constantly changing traditions.

  2. Impact of Ni promotion on the hydrogenation pathways of phenanthrene on MoS 2 /γ-Al 2 O 3

    Energy Technology Data Exchange (ETDEWEB)

    Schachtl, Eva; Yoo, Jong Suk; Gutiérrez, Oliver Y.; Studt, Felix; Lercher, Johannes A.

    2017-08-01

    The reaction network and elementary steps of the hydrogenation of phenanthrene are explored on parent and Ni-promoted MoS2/c-Al2O3. Two pathways were identified, i.e., Path 1: Phenanthrene _ 9,10-dihydrophenanthrene (DiHPhe)?1,2,3,4,4a,9,10,10a-octahydro-phenanthrene (asymOHPhe), and Path 2: Phenanthrene ?1,2,3,4-tetrahydrophenanthrene (TetHPhe)?1,2,3,4,5,6,7,8-octahydrophenan threne. The steps TetHPhe?asymOHPhe (hydrogenation), and DiHPhe?TetHPhe (hydrogenationisomerization) become notable at phenanthrene conversions above 20%. The reaction preferentially proceeds via Path 1 (90% selectivity) on MoS2/Al2O3. Ni promotion (Ni/(Ni + Mo) molar ratio of 0.3 at the edges on MoS2) increases the hydrogenation activity per active edge twofold and leads to 50% selectivity to both pathways. The reaction orders in H2 vary from _0.8 on MoS2/Al2O3 to _1.2 on Ni-MoS2/Al2O3, whereas the reaction orders in phenanthrene (_0.6) hardly depend on Ni promotion. The reaction orders in H2S are zero on MoS2/Al2O3 and slightly negative on Ni-MoS2/Al2O3. DFT calculations indicate that phenanthrene is preferentially adsorbed parallel to the basal planes, while H is located at the edges perpendicular to the basal planes. Theory also suggests that Ni atoms, incorporated preferentially on the S-edges, increase the stability of hydrogenated intermediates. Hydrogenation of phenanthrene proceeds through quasi-equilibrated adsorption of the reactants followed by consecutive addition of hydrogen pairs to the adsorbed hydrocarbon. The rate determining steps for the formation of DiHPhe and TetHPhe are the addition of the first and second hydrogen pair, respectively. The concentration of SH groups (activated H at the edges) increases with Ni promotion linearly correlating the rates of Path 1 and Path 2, albeit with different functions. The enhancing effect of Ni on Path 2 is attributed to accelerated hydrogen addition to adsorbed hydrocarbons without important changes in their coverages.

  3. Temperature-Mediated Selective Growth of MoS2 /WS2 and WS2 /MoS2 Vertical Stacks on Au Foils for Direct Photocatalytic Applications.

    Science.gov (United States)

    Shi, Jianping; Tong, Rui; Zhou, Xiebo; Gong, Yue; Zhang, Zhepeng; Ji, Qingqing; Zhang, Yu; Fang, Qiyi; Gu, Lin; Wang, Xina; Liu, Zhongfan; Zhang, Yanfeng

    2016-12-01

    A growth-temperature-mediated two-step chemical vapor deposition strategy is designed to synthesize MoS2 /WS2 and WS2 /MoS2 stacks on Au foils. Predominantly A-A stacked MoS2 /WS2 and A-B stacked WS2 /MoS2 are selectively achieved and confirmed. Relative enhancements or reductions in photocatalytic activities of MoS2 /WS2 or WS2 /MoS2 are observed under illumination, because the type-II band alignment enables directional electron flow from electrode to active site. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. PREPARATION AND CATALYTIC ACTIVITY FOR ISOPROPYL BENZENE CRACKING OF Co, Mo AND Co/Mo-Al2O3-PILLARED MONTMORILLONITE CATALYSTS

    Directory of Open Access Journals (Sweden)

    Hasanudin Hasanudin

    2010-06-01

    Full Text Available It has been prepared Co, Mo and Co/Mo-Al2O3-pillared montmorillonite catalysts using montmorillonite clay  as raw material. The structure and porosity of the catalysts were determined using N2 adsorption-desorption and FT-IR spectroscopy analysis methods. Isopropyl benzene cracking using these catalysts were used to test the catalytic activity and performance of Co, Mo and Co/Mo-Al2O3-pillared montmorillonites.  Characterization results showed that pillarization resulted in the increase of the total pore volume and specific surface area of the clay. Meanwhile, transition metals (Co, Mo and Co/Mo loaded on Al2O3-pillared monmorillonites could increase the catalytic activity of the catalysts for isopropyl benzene cracking significantly.   Keywords: pillared monmorillonite, isopropyl benzene  and cracking catalyst

  5. Overlay networks toward information networking

    CERN Document Server

    Tarkoma, Sasu

    2010-01-01

    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  6. Stable MoS2 Field-Effect Transistors Using TiO2 Interfacial Layer at Metal/MoS2 Contact

    KAUST Repository

    Park, Woojin

    2017-09-07

    Molybdenum disulphide (MoS2) is an emerging 2-dimensional (2D) semiconductor for electronic devices. However, unstable and low performance of MoS2 FETs is an important concern. In this study, inserting an atomic layer deposition (ALD) titanium dioxide (TiO2) interfacial layer between contact metal and MoS2 channel is suggested to achieve more stable performances. The reduced threshold voltage (VTH) shift and reduced series resistance (RSD) were simultaneously achieved.

  7. Large Lateral Photovoltage Observed in MoS2 Thickness-Modulated ITO/MoS2/p-Si Heterojunctions.

    Science.gov (United States)

    Qiao, Shuang; Zhang, Bin; Feng, Kaiyu; Cong, Ridong; Yu, Wei; Fu, Guangsheng; Wang, Shufang

    2017-05-31

    Molybdenum disulfide (MoS2), as a typical two-dimensional (2D) material, has attracted extensive attention in recent years because of its fascinating optical and electric properties. However, the applications of MoS2 have been mainly in photovoltaic devices, field-effect transistors, photodetectors, and gas sensors. Here, it is demonstrated that MoS2 can be found another important application in position sensitive detector (PSD) based on lateral photovoltaic effect (LPE) in it. The ITO/MoS2(3, 5, 7, 9, 10, 20, 50, 100 nm)/p-Si heterojunctions were successfully prepared with vertically standing nanosheet structure of MoS2. Because of the special structure and the strong light absorption of the relatively thick MoS2 film, the ITO/MoS2/p-Si heterojunction exhibits an abnormal thickness-dependent LPE, which can be ascribed to the n- to p-type transformation of MoS2. Moreover, the LPE of ITO/MoS2/p-Si structure improves greatly because of forward enhanced built-in field by type transformation in a wide spectrum response ranging from visible to near-infrared, especially the noticeable improvement in infrared region, indicating its great potential application in infrared PSDs. This work not only suggest that the ITO/MoS2/p-Si heterojunction shows great potential in LPE-based sensors, but also unveils the importance of type transformation of MoS2 in MoS2-based photoelectric devices besides strong light absorption and suitable bandgap.

  8. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC...

  9. Sensor networks

    NARCIS (Netherlands)

    Chatterjea, Supriyo; Thurston, J.; Kininmonth, S.; Havinga, Paul J.M.

    2006-01-01

    This article describes the details of a sensor network that is currently being deployed at the Great Barrier Reef in Australia. The sensor network allows scientists to retrieve sensor data that has a high spatial and temporal resolution. We give an overview of the energy-efficient data aggregation

  10. Network Protocols

    NARCIS (Netherlands)

    Tanenbaum, A.S.

    1981-01-01

    Dunng the last ten years, many computer networks have been designed, implemented, and put into service in the United States, Canada, Europe, Japan, and elsewhere. From the experience obtamed with these networks, certain key design principles have begun to emerge, principles that can be used to

  11. Probabilistic Networks

    DEFF Research Database (Denmark)

    Jensen, Finn Verner; Lauritzen, Steffen Lilholt

    2001-01-01

    This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs.......This article describes the basic ideas and algorithms behind specification and inference in probabilistic networks based on directed acyclic graphs, undirected graphs, and chain graphs....

  12. Organizational Networks

    DEFF Research Database (Denmark)

    Sørensen, Ole Henning; Grande, Bård

    1996-01-01

    The paper focuses on the concept of organizational networks. Four different uses of the concept are identified and critically discussed.......The paper focuses on the concept of organizational networks. Four different uses of the concept are identified and critically discussed....

  13. Affective Networks

    OpenAIRE

    Jodi Dean

    2010-01-01

    This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  14. Processing of Mo-Si-B intermetallics by extrusion and oxidation properties of the extruded Tl-MoSi2-MoB System

    Energy Technology Data Exchange (ETDEWEB)

    Summers, Eric [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    An extrusion process was developed that is able to consistently produce large quantities of Mo-Si-B rods without the presence of defects. Binder removal from the extruded rods was studied in detail and it was determined that heating rates on the order of 0.02°/minute (1.2°/hour) are necessary to remove the binder without the formation of defects. This low heating rate resulted in debinding times in excess of 70 hours (approximately 3 days). Wicking was investigated as a means to decrease the time necessary for binder removal. Using 0.05μm alumina powder as a wicking agent, binder removal times were reduced to 10 hours with heating rates up to 1°/minute employed without defect formation. Once the extrusion process was complete the oxidation properties of the Tl-MoSi2-MoB extruded phase assemblage was investigated. It was determined that this composition exhibits catastrophic oxidation or pesting in the temperature range of 660-760°C, resulting in the material turning to dust. Outside of this temperature range the composition is oxidatively stable. Continuous mass measurements were taken at 1,300, 1,450, and 1,600 C to determine the oxidation rate constants of this material. Parabolic rate constants of 6.9 x 10-3, 1.3 x 10-3, and 9.1 x 10-3 mg2/cm4/hr were determined for 1,300, 1,450, and 1,600 C respectively.

  15. Network chemistry, network toxicology, network informatics, and network behavioristics: A scientific outline

    OpenAIRE

    WenJun Zhang

    2016-01-01

    In present study, I proposed some new sciences: network chemistry, network toxicology, network informatics, and network behavioristics. The aims, scope and scientific foundation of these sciences are outlined.

  16. Network Affordances

    DEFF Research Database (Denmark)

    Samson, Audrey; Soon, Winnie

    2015-01-01

    This paper examines the notion of network affordance within the context of network art. Building on Gibson's theory (Gibson, 1979) we understand affordance as the perceived and actual parameters of a thing. We expand on Gaver's affordance of predictability (Gaver, 1996) to include ecological...... and computational parameters of unpredictability. We illustrate the notion of unpredictability by considering four specific works that were included in a network art exhibiton, SPEED SHOW [2.0] Hong Kong. The paper discusses how the artworks are contingent upon the parameteric relations (Parisi, 2013......), of the network. We introduce network affordance as a dynamic framework that could articulate the experienced tension arising from the (visible) symbolic representation of computational processes and its hidden occurrences. We base our proposal on the experience of both organising the SPEED SHOW and participating...

  17. Basal-Plane Ligand Functionalization on Semiconducting 2H-MoS2 Monolayers.

    Science.gov (United States)

    Ding, Qi; Czech, Kyle J; Zhao, Yuzhou; Zhai, Jianyuan; Hamers, Robert J; Wright, John C; Jin, Song

    2017-04-12

    Molybdenum disulfide (MoS2) is a two-dimensional material promising for electronic, optical, and catalytic applications. To fully harness its potential, functionalization is essential to controlling its properties. However, MoS2 functionalization has been mostly limited to either 1T-phase MoS2 or the edges of 2H-phase MoS2, and the chemistry of covalent functionalization on the basal plane of 2H-MoS2 is poorly understood. Here, we report a facile approach to covalently functionalize chemical vapor deposition (CVD) grown 2H-MoS2 monolayers (MLs), as well as mechanically exfoliated MoS2, via thiol conjugation at sulfur vacancies on the basal plane. Thorough characterization confirmed the functionalization by thiol molecules on MoS2 MLs, and we experimentally proved that sulfur vacancies in MoS2 MLs play a key role in the functionalization of basal planes. By the controlling of the amount of sulfur vacancies via sulfur annealing, the degree of MoS2 functionalization was effectively tuned. Because thiol conjugation partially repairs or passivates sulfur vacancies, enhanced photoluminescence response and decreased active sites for hydrogen evolution catalysis were observed for functionalized MoS2. Moreover, such functionalization can be utilized for making MoS2-based heterostructures, an example of which was demonstrated using a dithiol molecule to link MoS2 layers and PbSe quantum dots. These results provide new understanding and insights on the surface chemistry of MoS2 and open up more opportunities for MoS2 MLs with well-controlled properties and broader applications.

  18. What the flux? Deriving empirical estimates of riverine Mo fluxes over Earth history

    Science.gov (United States)

    Romaniello, S. J.; Ostrander, C. M.; Johnson, A.; Planavsky, N.; Anbar, A. D.

    2016-12-01

    Molybdenum (Mo) is a key micronutrient in the marine nitrogen cycle and thus plays an important role in regulating global marine primary productivity and biogeochemistry. At present, Mo is the most abundant transition metal in seawater, despite being one of the least abundant transition metals in crustal rocks. This counterintuitive behavior is the result of the high solubility and mobile nature of the molybdate anion under oxidizing conditions. However, previous studies have pointed out that the oxidative weathering flux of Mo to the ocean was likely much lower under Archean conditions, and that when coupled with reduced solubility of Mo in anoxic seawater, portions of the ocean may have been Mo starved. With few exceptions, riverine fluxes of elements have been only poorly constrained over geologic time. In the absence of strong empirical constraints, fluxes are either imagined to have been similar to today, or radically different, depending primarily on the chemistry of the element and model implored by the authors. Based on large variations of Mo concentrations in shales, several authors have invoked models where riverine Mo fluxes vary in response to atmospheric O2 availability but it has been difficult to provide independent constraints to support or refute these models. Here we demonstrate a novel approach for constraining riverine Mo fluxes from the Archean to present by independently estimating the seawater Mo inventory from Mo/TOC ratios and the Mo residence time from Mo isotope ratios. At steady state, the riverine flux is then the ratio of these parameters. Surprisingly, despite strong secular evolution of seawater Mo concentrations and residence time, this approach suggests the overall rate of Mo supply to the ocean was probably relatively constant within one order of magnitude over most of Earth history. This result provides new insights into both the processes controlling Mo availability to the oceans and, more broadly, the controls on oxidative

  19. Preparation of Monolayer MoS2 Quantum Dots using Temporally Shaped Femtosecond Laser Ablation of Bulk MoS2 Targets in Water.

    Science.gov (United States)

    Li, Bo; Jiang, Lan; Li, Xin; Ran, Peng; Zuo, Pei; Wang, Andong; Qu, Liangti; Zhao, Yang; Cheng, Zhihua; Lu, Yongfeng

    2017-09-11

    Zero-dimensional MoS2 quantum dots (QDs) possess distinct physical and chemical properties, which have garnered them considerable attention and facilitates their use in a broad range of applications. In this study, we prepared monolayer MoS2 QDs using temporally shaped femtosecond laser ablation of bulk MoS2 targets in water. The morphology, crystal structures, chemical, and optical properties of the MoS2 QDs were characterized by transmission electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, UV-vis absorption spectra, and photoluminescence spectra. The analysis results show that highly pure, uniform, and monolayer MoS2 QDs can be successfully prepared. Moreover, by temporally shaping a conventional single pulse into a two-subpulse train, the production rate of MoS2 nanomaterials (including nanosheets, nanoparticles, and QDs) and the ratio of small size MoS2 QDs can be substantially improved. The underlying mechanism is a combination of multilevel photoexfoliation of monolayer MoS2 and water photoionization-enhanced light absorption. The as-prepared MoS2 QDs exhibit excellent electrocatalytic activity for hydrogen evolution reactions because of the abundant active edge sites, high specific surface area, and excellent electrical conductivity. Thus, this study provides a simple and green alternative strategy for the preparation of monolayer QDs of transition metal dichalcogenides or other layered materials.

  20. Investigating Visible-Photocatalytic Activity of MoS2/TiO2 Heterostructure Thin Films at Various MoS2 Deposition Times

    Directory of Open Access Journals (Sweden)

    Hang Nguyen Thai Phung

    2017-01-01

    Full Text Available MoS2/TiO2 heterostructure thin films were fabricated by sol-gel and chemical bath deposition methods. Crystal structure, surface morphology, chemical states of all elements, and optical property of the obtained thin films were characterized by using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis spectroscopy techniques, respectively. Photocatalytic activity of all thin films was evaluated by measuring decomposition rate of methylene blue solution under visible light irradiation. The results indicate that ultrathin MoS2 film on TiO2-glass substrate improves photocatalytic activity of TiO2 in the visible light due to the efficient absorption of visible photon of MoS2 few layers and the transfer of electrons from MoS2 to TiO2. All MoS2/TiO2 heterostructure thin films exhibit higher visible light photocatalytic activity than that of pure MoS2 and TiO2 counterparts. The best MoS2/TiO2 heterostructure thin film at MoS2 layer deposition time of 45 minutes can decompose about 60% MB solution after 150 minutes under visible light irradiation. The mechanism of the enhancement for visible-photocatalytic activity of MoS2/TiO2 heterostructure thin film was also discussed.

  1. Structure and electronic properties of Cu nanoclusters supported on Mo{sub 2}C(001) and MoC(001) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Posada-Pérez, Sergio; Viñes, Francesc; Illas, Francesc, E-mail: francesc.illas@ub.edu [Departament de Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, c/ Martí i Franquès 1, 08028 Barcelona (Spain); Rodríguez, José A. [Chemistry Department, Brookhaven National Laboratory, Bldg. 555, Upton, New York 11973 (United States)

    2015-09-21

    The atomic structure and electronic properties of Cu{sub n} nanoclusters (n = 4, 6, 7, and 10) supported on cubic nonpolar δ-MoC(001) and orthorhombic C- or Mo-terminated polar β-Mo{sub 2} C(001) surfaces have been investigated by means of periodic density functional theory based calculations. The electronic properties have been analyzed by means of the density of states, Bader charges, and electron localization function plots. The Cu nanoparticles supported on β-Mo{sub 2} C(001), either Mo- or C-terminated, tend to present a two-dimensional structure whereas a three-dimensional geometry is preferred when supported on δ-MoC(001), indicating that the Mo:C ratio and the surface polarity play a key role determining the structure of supported clusters. Nevertheless, calculations also reveal important differences between the C- and Mo-terminated β-Mo{sub 2} C(001) supports to the point that supported Cu particles exhibit different charge states, which opens a way to control the reactivity of these potential catalysts.

  2. Neutron diffraction study of the crystal structure of BaMoO{sub 4}: A suitable precursor for metallic BaMoO{sub 3} perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Nassif, V.; Carbonio, R.E. [Univ. Nacional de Cordoba (Argentina). Inst. de Investigaciones en Fisicoquimica; Alonso, J.A. [C.S.I.C., Madrid (Spain). Inst. de Ciencia de Materiales

    1999-08-01

    BaMoO{sub 3}, metallic and Pauli paramagnetic, has been prepared by controlled reduction of BaMoO{sub 4}. This precursor, containing Mo(VI), is unusually stable against reduction, due to structural factors. The crystal structure of BaMoO{sub 4} has been refined from neutron powder diffraction data: space group I4{sub 1}/a (no. 88), Z = 4, a = 5.5479(9), and c = 12.743(2) {angstrom}. A bond-valence study allowed the authors to detect the presence of slight tensile and compressive stresses in the crystal structure of BaMoO{sub 4}, in which Ba is overbonded and Mo is underbonded. However, this effect is less pronounced than in other AMO{sub 4} oxides with a scheelite structure (A = Ca, Sr, Ba; M = Mo, W): BaMoO{sub 4} contains the M cation exhibiting the closest valence to the nominal value of 6+, suggesting a large covalent contribution to the Mo-O bonds. This observation is coherent with the large thermal stability of this compound against reduction, taking place at temperatures above 920 C in H{sub 2} flow.

  3. Facile synthesis of uniform MoO2/Mo2CTx heteromicrospheres as high-performance anode materials for lithium-ion batteries

    Science.gov (United States)

    Min, Jie; Wang, Kangyan; Liu, Jun; Yao, Yang; Wang, Wenjun; Yang, Linyu; Zhang, Ruizhi; Lei, Ming

    2017-09-01

    Uniform nano/micro-spherical MoO2/Mo2CTx (T = O) heterostructures have been synthesized through a heterocatalytic reaction with subsequent facile calcinations. Given the high activity of HxMoO3/C precursors, this strategy opens a low-temperature route to realize the fabrication of nanocrystalline MoO2/Mo2CTx heterostructures, leading to achieve rapidly activated conversion reaction and extrinsic pseudocapacitive behaviour. Rather than carbon, highly conductive Mo2CTx decreases the charge transfer resistance in MoO2 and maintains its structural stability upon lithiation/delithiation, ensuring the heterostructures with excellent cyclability (e.g., up to 833 mA h g-1 at 100 mA g-1 for 160 cycles with 95% capacity retention) and high rate capability (e.g., 665 mA h g-1 at 1 A g-1). Additionally, owing to the carbon-free characteristic, the secondary nano/microstructure feature and the suppressed surface oxidation trait, MoO2/Mo2CTx heterostructures, therefore, can deliver an improved initial Coulombic efficiency (e.g., up to 78% at 100 mA g-1). The present oxycarbide transformation and hybridization strategies are facile but effective, and they are very promising to be applied to converting other oxides-carbon composites into oxides/carbides heterostructures towards achieving higher electrochemical performance.

  4. Synthesis of 3D-MoO2 microsphere supported MoSe2 as an efficient electrocatalyst for hydrogen evolution reaction

    Science.gov (United States)

    Luo, Jiaxian; Xu, Peiman; Zhang, Dawei; Wei, Licheng; Zhou, Dan; Xu, Weiming; Li, Jingwei; Yuan, Dingsheng

    2017-11-01

    Many efforts have been devoted to the exploration of non-noble-metal electrocatalysts for the hydrogen evolution reaction (HER) in recent years. Here, we have developed a 3D-MoO2 microsphere supported MoSe2 for HER, via a facile hydrothermal approach followed by selenylation treatment. Loosely stacked MoSe2 layers are formed on the conductive MoO2 surface, and act as active sites for HER. Meanwhile, the metallic inner MoO2 facilitates electron transport for proton reduction. In addition, the MoSe2 could protect the inner MoO2 from the acidic electrolyte in the HER precess. Significantly, the as-synthesized MoO2/MoSe2 exhibits excellent catalytic activity for HER, characterised by a low onset potential of ‑101 mV vs reversible hydrogen electrode, a small overpotential of 167 mV at a current density of 10 mA cm‑2, along with Tafel slope values of 68 mV dec‑1, as well as outstanding stability in 0.5 mol L‑1 H2SO4.

  5. Electromagnetic structure of sup 9 sup 8 Mo

    CERN Document Server

    Zielinska, M; Choinski, J; Iwanicki, J; Napiorkowski, P J; Srebrny, J; Toh, Y; Oshima, M; Osa, A; Utsuno, Y; Hatsukawa, Y; Katakura, J; Koizumi, M; Matsuda, M; Shizuma, T; Sugawara, M; Morikawa, T; Kusakari, H; Efimov, A D; Mikhailov, V M

    2002-01-01

    The nucleus sup 9 sup 8 Mo was multiply Coulomb excited using sup 2 sup 0 Ne, sup 8 sup 4 Kr and sup 1 sup 3 sup 6 Xe beams. Eighteen E2 and M1 reduced matrix elements connecting 7 low-lying levels have been determined using the least-squares code GOSIA. The results are compared with the predictions of an extended version of the IBM1 model. The quadrupole sum rules approach was used to determine the shape parameters in two 0 sup + (ground and first excited) states. The rotational invariants and obtained show the shape coexistence in sup 9 sup 8 Mo nucleus: the triaxial ground state and the prolate first excited state.

  6. Simple MoCap System for Home Usage

    Directory of Open Access Journals (Sweden)

    Martin Magdin

    2017-08-01

    Full Text Available Nowadays many MoCap systems exist. Generating 3D facial animation of characters is currently realized by using the motion capture data (MoCap data, which is obtained by tracking the facial markers from an actor/actress. In general it is a professional solution that is sophisticated and costly. This paper presents a solution with a system that is inexpensive. We propose a new easy-to-use system for home usage, through which we are making character animation. In its implementation we paid attention to the elimination of errors from the previous solutions. In this paper the authors describe the method how motion capture characters on a treadmill and as well as an own Java application that processes the video for its further use in Cinema 4D. This paper describes the implementation of this technology of sensing in a way so that the animated character authentically imitated human movement on a treadmill.

  7. ¿Cómo de real vemos el mundo?

    Directory of Open Access Journals (Sweden)

    Antonia Pilar Pacheco Unguetti

    2011-12-01

    Full Text Available La percepción es un fenómeno complejo. No siempre ‘vemos’ las cosas como son en realidad. La forma con que cada cultura interactúa con su entorno, el aprendizaje o las emociones son factores que determinan cómo percibimos lo que nos rodea, y nos predisponen a ver el vaso medio lleno o medio vacío. Las ilusiones ópticas han sido un fenómeno de interés para los psicólogos desde hace décadas, pero ¿quién no se ha preguntado alguna vez cómo de real es su mundo?

  8. Parametric amplification in MoS2drum resonator.

    Science.gov (United States)

    Prasad, Parmeshwar; Arora, Nishta; Naik, A K

    2017-11-30

    Parametric amplification is widely used in diverse areas from optics to electronic circuits to enhance low level signals by varying relevant system parameters. Parametric amplification has also been performed in several micro-nano resonators including nano-electromechanical system (NEMS) resonators based on a two-dimensional (2D) material. Here, we report the enhancement of mechanical response in a MoS 2 drum resonator using degenerate parametric amplification. We use parametric pumping to modulate the spring constant of the MoS 2 resonator and achieve a 10 dB amplitude gain. We also demonstrate quality factor enhancement in the resonator with parametric amplification. We investigate the effect of cubic nonlinearity on parametric amplification and show that it limits the gain of the mechanical resonator. Amplifying ultra-small displacements at room temperature and understanding the limitations of the amplification in these devices is key for using these devices for practical applications.

  9. TexMo: A Multi-language Development Environment

    DEFF Research Database (Denmark)

    Pfeiffer, Rolf-Helge; Wasowski, Andrzej

    2012-01-01

    Contemporary software systems contain a large number of artifacts expressed in multiple languages, ranging from domain-specific languages to general purpose languages. These artifacts are interrelated to form software systems. Existing development environments insufficiently support handling...... relations between artifacts in multiple languages. This paper presents a taxonomy for multi-language development environments, organized according to language representation, representation of relations between languages, and types of these relations. Additionally, we present TexMo, a prototype of a multi-language...... development environment, which uses an explicit relation model and implements visualization, static checking, navigation, and refactoring of cross-language relations. We evaluate TexMo by applying it to development of a web-application, JTrac, and provide preliminary evidence of its feasibility by running...

  10. Pore growth in U-Mo/Al dispersion fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeon Soo; Jeong, G. Y.; Sohn, D. -S.; Jamison, L. M.

    2016-09-01

    U-Mo/Al dispersion fuel is currently under development in the DOE’s Material Management and Minimization program to convert HEU-fueled research reactors to LEU-fueled reactors. In some demanding conditions in high-power and high-performance reactors, large pores form in the interaction layers between the U-Mo fuel particles and the Al matrix, which pose a potential to cause fuel failure. In this study, comprehension of the formation and growth of these pores was explored. As a product, a model to predict pore growth and porosity increase was developed. Well-characterized in-pile data from reduced-size plates were used to fit the model parameters. A data set of full-sized plates, independent and distinctively different from those used to fit the model parameters, was used to examine the accuracy of the model.

  11. Design and Testing of Subsystems for Mo-99 Production

    Energy Technology Data Exchange (ETDEWEB)

    Gromov, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Virgo, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Chemerisov, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, G. F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-01-01

    Argonne National Laboratory, in cooperation with Los Alamos National Laboratory, is developing technology with NorthStar Medical Technologies to produce 99Mo from the γ,n reaction on a 100Mo target in an electron accelerator. During production runs and thermal testing of the helium-cooled target, it became obvious that a production-scale beam-line configuration would need a collimator to protect the target from accidental beam misplacement or a beam-profile change. A prototype high-power collimator and beam stop were designed and fabricated. Testing indicated that they will be able to operate at full power in the production-scale accelerator.

  12. Performance comparison of MoNA and LISA neutron detectors

    Science.gov (United States)

    Purtell, Kimberly; Rethman, Kaitlynne; Haagsma, Autumn; Finck, Joseph; Smith, Jenna; Snyder, Jesse

    2010-11-01

    In 2002 eight primarily undergraduate institutions constructed and tested the Modular Neutron Array (MoNA) which has been used to detect high energy neutrons at the National Superconducting Cyclotron Laboratory (NSCL). Nine institutions have now designed, constructed and tested the Large-area multi-Institutional Scintillator Array (LISA) neutron detector which will be used at the NSCL and the future Facility for Rare Isotope Beams (FRIB). Both detectors are comprised of 144 detector modules. Each module is a 200 x 10 x 10 cm^3 bar organic plastic scintillator with a photomultiplier tube mounted on each end. Using cosmic rays and a gamma source, we compared the performance of MoNA and LISA by using the same electronics to check light attenuation, position resolution, rise times, and cosmic ray peak widths. Results will be presented.

  13. ¿Cómo nos mira Débora Arango?

    Directory of Open Access Journals (Sweden)

    Ricardo Sánchez

    1996-01-01

    Full Text Available ¿Cómo la miraban sus contemporáneos y cómo la miramos hoy; nosotros, gente de final del siglo y del milenio??? Tal parece una buena perspectiva para evaluar y dilucidar el sentido de su obra, hoy colgada en la Luis Ángel Arango. Inquietante en sus distintas significaciones de imágenes, formas, colores, materiales, interpelaciones. Polifónica por los caminos escogidos: el retrato, el desnudo, lo social, lo político. Figurativa y expresionista por la semántica de los lenguajes pictóricos. Realista crítica y testimonial por las tendencias conceptuales y de escuela en que se manifiesta su arte.

  14. Synthesis and reactivity of dimolybdathiaborane cluster [(Cp Mo ...

    Indian Academy of Sciences (India)

    848. Kiran Kumar Varma Chakrahari and Sundargopal Ghosh of solvent from the filtrate, the residue was subjected to chromatographic work-up using silica gel TLC plates. Elution with hexane:CH2Cl2 (95:05 v/v) mixture afforded the following compounds in order of elution: Green [(Cp. ∗. Mo)2B4SH6], 1 (0.35g, 48%) and ...

  15. Anomalous hydrocracking of triglycerides over CoMo-catalyst ...

    Indian Academy of Sciences (India)

    Currently, industry and transport sector are inherently based on costly and unsustainable crude oil sources. There is an increasingly recognized need to slow down .... 9.39 wt% O, 4.0 ppm S) was hydroprocessed in a fixed-bed reactor over a sulphided Co-Mo/Al2O3 cat- alyst. Catalysts (2.5 ml) mixed with SiC (2.5 ml) to.

  16. GO RUTA SETSWANA 0 IKAEGILE MO SETSO -TIKOLOGONG

    African Journals Online (AJOL)

    bana bogolo 1 Dithamalakwane ke1 farafarileng. o lhale, nt1hot1ho. ruta a o ot1 mosola hoko di oketsa mo 1 e pile ba dithamalakwane fa ka kgona morutabana nako Ke go go baneng ya ke Di 1emogi1e kitso t1ha1osa itse mongwe na di thuto. kwa ba a le ka le lemoga metlae fa Batswana. sekolong wa dil go di1o go ...

  17. Is Single Layer MoS2 Stable in the Air?

    Science.gov (United States)

    Martincová, Jana; Otyepka, Michal; Lazar, Petr

    2017-09-21

    Molybdenum disulfide (MoS2 ) is extensively studied because of its potential applications in catalysis, electronic and optoelectronic devices, and composite nanostructures. However, a recent experimental study indicated that, contrary to current beliefs, MoS2 monolayers lack long-term stability in air. Here, a study is presented on the oxidation of MoS2 monolayers based on density functional theory (DFT) calculations. The results suggest that single-layer MoS2 samples with exposed edge sites are indeed unstable to oxidation, which occurs because of the low energetic barrier to dissociation of oxygen molecules at the Mo-edges of MoS2 . After an oxygen molecule dissociates, oxygen atoms replace sulfur atoms, and further oxidation causes the formation of a one-dimensional chain-like structure resembling that of bulk MoO3 . This MoO3 structure facilitates the spread of oxidation onto the surface, and the stress associated with the misfit between the MoS2 and MoO3 lattices may cause the experimentally observed cracking of MoS2 flakes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. 800 C isothermal section of the Co-Cr-Mo-Si quaternary system

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Songlin; Yin, Fucheng; Zhang, Minghua; Zhao, Manxiu; Li, Zhi [Xiangtan Univ., Hunan (China). School of Mechanical Engineering; Xiangtan Univ., Hunan (China). Key Laboratory of Materials Design and Preparation Technology of Hunan Province

    2014-12-15

    The 800 C isothermal section of the Co-Cr-Mo-Si quaternary system with the Co content fixed at 70 at.% and different contents of Cr, Mo and Si was determined by means of X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. Twelve different phase regions could be identified; one of them being a wide (Co) + Co{sub 3}Mo{sub 2}Si phase field, but only one four-phase region consisting of (Co) + Co{sub 3}Mo + Co{sub 7}Mo{sub 6} + Co{sub 3}Mo{sub 2}Si was experimentally confirmed. The measured solubility of Si in the Co{sub 3}Mo phase is rather limited but could reach up to 15.1 at.% in Co{sub 7}Mo{sub 6}. The solubility of Cr in Co{sub 3}Mo and Co{sub 7}Mo{sub 6} was measured to be as high as 13.4 and 23.3 at.%, respectively, and the maximum solubility of Cr in (Co), αCo{sub 2}Si and Co{sub 3}Mo{sub 2}Si could reach 26.9, 5.6 and 12.5 at.%, respectively.

  19. Photocatalytic Stability of Single- and Few-Layer MoS₂.

    Science.gov (United States)

    Parzinger, Eric; Miller, Bastian; Blaschke, Benno; Garrido, Jose A; Ager, Joel W; Holleitner, Alexander; Wurstbauer, Ursula

    2015-11-24

    MoS2 crystals exhibit excellent catalytic properties and great potential for photocatalytic production of solar fuels such as hydrogen gas. In this regard, the photocatalytic stability of exfoliated single- and few-layer MoS2 immersed in water is investigated by μ-Raman spectroscopy. We find that while the basal plane of MoS2 can be treated as stable under photocatalytic conditions, the edge sites and presumably also defect sites are highly affected by a photoinduced corrosion process. The edge sites of MoS2 monolayers are significantly more resistant to photocatalytic degradation compared to MoS2 multilayer edge sites. The photostability of MoS2 edge sites depends on the photon energy with respect to the band gap in MoS2 and also on the presence of oxygen in the electrolyte. These findings are interpreted in the framework of an oxidation process converting MoS2 into MoOx in the presence of oxygen and photoinduced charge carriers. The high stability of the MoS2 basal plane under photocatalytic treatment under visible light irradiation of extreme light intensities on the order of P ≈ 10 mW/μm(2) substantiates MoS2's potential as photocatalyst for solar hydrogen production.

  20. Hierarchical MoS2@MoP core-shell heterojunction electrocatalysts for efficient hydrogen evolution reaction over a broad pH range

    Science.gov (United States)

    Wu, Aiping; Tian, Chungui; Yan, Haijing; Jiao, Yanqing; Yan, Qing; Yang, Guoyu; Fu, Honggang

    2016-05-01

    A low-cost catalyst for the hydrogen evolution reaction (HER) over a broad pH range is highly desired to meet the practical needs in different areas. In this study, hierarchical flower-like MoS2@MoP core-shell heterojunctions (HF-MoSP) are designed as a promising catalyst for HER over a broad pH range. The materials are obtained by the controllable phosphidation of the hierarchical MoS2 flower (HF-MoS2) composed of thin silk belt-like sheets. The phosphidation degree, P/S ratio and work function (WF) of HF-MoSP can be tuned easily over broad range by changing the phosphidation temperature. Under optimized condition, HF-MoSP exhibits excellent electrocatalytic activity for HER with a low onset overpotential of 29 mV and η of 108 mV at 10 mA cm-2 in 0.5 M H2SO4 and retains its good activity for 30 h. In addition, the catalyst shows excellent activity in 1 M KOH with an onset overpotential of 42 mV and η of 119 mV at 10 mA cm-2. The catalysts also exhibit obvious activity in neutral, weak acid and weak alkaline conditions. The good performance is relative to the synergy of the MoP shell and MoS2 core and the high WF of HF-MoSP close to Pt, and the large SBET of HF-MoSP benefited from the hierarchical structure. This study represents the construction of the core-shell heterojunction and provides a new way to provide the low-cost and high-performance catalyst for HER.A low-cost catalyst for the hydrogen evolution reaction (HER) over a broad pH range is highly desired to meet the practical needs in different areas. In this study, hierarchical flower-like MoS2@MoP core-shell heterojunctions (HF-MoSP) are designed as a promising catalyst for HER over a broad pH range. The materials are obtained by the controllable phosphidation of the hierarchical MoS2 flower (HF-MoS2) composed of thin silk belt-like sheets. The phosphidation degree, P/S ratio and work function (WF) of HF-MoSP can be tuned easily over broad range by changing the phosphidation temperature. Under optimized

  1. The lanthanum(III molybdate(VI La4Mo7O27

    Directory of Open Access Journals (Sweden)

    Petra Becker

    2009-08-01

    Full Text Available Crystals of the orthorhombic phase La4Mo7O27 (lanthanum molybdenum oxide were obtained from a non-stoichiometric melt in the pseudo-ternary system La2O3–MoO3–B2O3. In the crystal structure, distorted square-antiprismatic [LaO8] and monocapped square-antiprismatic [LaO9] polyhedra are connected via common edges and faces into chains along [010]. These chains are arranged in layers that alternate with layers of [MoO4] and [MoO5] polyhedra parallel to (001. In the molybdate layers, a distorted [MoO5] trigonal bipyramid is axially connected to two [MoO4] tetrahedra, forming a [Mo3O11] unit.

  2. Microstructure Characterization of WCCo-Mo Based Coatings Produced Using High Velocity Oxygen Fuel

    Directory of Open Access Journals (Sweden)

    Serkan Islak

    2015-12-01

    Full Text Available The present study has been carried out in order to investigate the microstructural properties of WCCo-Mo composite coatings deposited onto a SAE 4140 steel substrate by high velocity oxygen fuel (HVOF thermal spray. For this purpose, the Mo quantity added to the WCCo was changed as 10, 20, 30 and 40 wt. % percents. The coatings are compared in terms of their phase composition, microstructure and hardness. Phase compound and microstructure of coating layers were examined using X-ray diffractometer (XRD and scanning electron microscope (SEM. XRD results showed that WCCo-Mo composite coatings were mainly composed of WC, W2C, Co3W3C, Mo2C, MoO2, Mo and Co phases. The average hardness of the coatings increased with increasing Mo content.

  3. Microstructures and Electrochemical Behavior of Ti-Mo Alloys for Biomaterials

    Directory of Open Access Journals (Sweden)

    Back-Sub Sung

    2015-01-01

    Full Text Available The Ti alloy with 7 wt% Mo revealed a microstructure that contained only the orthorhombic α′′ phase of a fine acicular martensitic structure. The corrosion resistance of the Ti-Mo alloys increased as the Mo content increased. Based on the results obtained from the polarization curve and electrochemical impedance, the Ti-Mo alloys were shown to be corrosion resistant because of the passive films formed on their surfaces. No ion release was detected in SBF (simulated body fluid solution, while Ti ions were released in 0.1% lactic acid ranging from 0.05 to 0.12 μg/mL for the Ti-Mo alloys. In vitro tests showed that MC3T3-E1 cell proliferation on Ti-7 wt% Mo alloy was rather active compared to other Ti-Mo alloys and commercial-grade pure Ti.

  4. Tailored MoS2 nanorods: a simple microwave assisted synthesis

    Science.gov (United States)

    Reshmi, S.; Akshaya, M. V.; Satpati, Biswarup; Roy, Anupam; Basu, Palash Kumar; Bhattacharjee, K.

    2017-11-01

    We report here the synthesis of MoS2 nanostructures by a simple liquid phase exfoliation of MoS2 powder in organic solvents followed by microwave treatment. The probe sonication and the microwave treatment play an important role in rolling and curling of the MoS2 nanosheets to give rise to MoS2 spheres and rod/tube like-structures with diameter approximately 150–200 nm. The MoS2 nanorods formed in this fashion are hollow inside with a wall thickness of 15–20 nm and the length of the nanorods is found in the order of several micrometers. Synthesis of such tailored MoS2 nanorods by liquid phase exfoliation is not yet reported. Our observations suggest the 2H phase of bulk MoS2 remains preserved in the nanostructures with high crystalline quality.

  5. Morphology, magnetic, magnetoresistance and optical properties of Co-Ni-Mo alloys thin films

    Energy Technology Data Exchange (ETDEWEB)

    Tanase, S.I., E-mail: tanase_sorin2006@yahoo.com [Faculty of Physics, ' Alexandru Ioan Cuza' University, Iasi, 700506 (Romania); Department of Physics, ' Alexandru Cel Bun' College, Gura Humorului, 725300 (Romania); Tanase, D. Pinzaru; Dobromir, M.; Georgescu, V. [Faculty of Physics, ' Alexandru Ioan Cuza' University, Iasi, 700506 (Romania)

    2011-10-01

    We present in this paper several results concerning the preparation by means of electrolysis and characterization of Co-Ni-Mo thin films. Co-Ni-Mo thin films with different molybdenum content in the range 0-25 at% Mo were prepared from a complex solution containing ions of Co, Ni and Mo, using galvanostatic control, on aluminum substrates. The effects of applied current density on the morphology, magnetic, magnetoresistance, and optical properties of the electrodeposited Co-Ni-Mo films were investigated. The applied current density significantly influenced the film composition and their magnetic properties. The increase of molybdenum content in Co-Ni films (up to 25 at% Mo) enhances the resistivity, but it reduces the magnetoresistance effect. We report the first observation of magnetoresistance as high as 8% in Co-Ni-Mo thin films.

  6. Energy Dissipation in Monolayer MoS2 Electronics.

    Science.gov (United States)

    Yalon, Eilam; McClellan, Connor J; Smithe, Kirby K H; Muñoz Rojo, Miguel; Xu, Runjie Lily; Suryavanshi, Saurabh V; Gabourie, Alex J; Neumann, Christopher M; Xiong, Feng; Farimani, Amir Barati; Pop, Eric

    2017-06-14

    The advancement of nanoscale electronics has been limited by energy dissipation challenges for over a decade. Such limitations could be particularly severe for two-dimensional (2D) semiconductors integrated with flexible substrates or multilayered processors, both being critical thermal bottlenecks. To shed light into fundamental aspects of this problem, here we report the first direct measurement of spatially resolved temperature in functioning 2D monolayer MoS2 transistors. Using Raman thermometry, we simultaneously obtain temperature maps of the device channel and its substrate. This differential measurement reveals the thermal boundary conductance of the MoS2 interface with SiO2 (14 ± 4 MW m-2 K-1) is an order magnitude larger than previously thought, yet near the low end of known solid-solid interfaces. Our study also reveals unexpected insight into nonuniformities of the MoS2 transistors (small bilayer regions) which do not cause significant self-heating, suggesting that such semiconductors are less sensitive to inhomogeneity than expected. These results provide key insights into energy dissipation of 2D semiconductors and pave the way for the future design of energy-efficient 2D electronics.

  7. IRRADIATION PERFORMANCE OF U-Mo MONOLITHIC FUEL

    Directory of Open Access Journals (Sweden)

    M.K. MEYER

    2014-04-01

    Full Text Available High-performance research reactors require fuel that operates at high specific power to high fission density, but at relatively low temperatures. Research reactor fuels are designed for efficient heat rejection, and are composed of assemblies of thin-plates clad in aluminum alloy. The development of low-enriched fuels to replace high-enriched fuels for these reactors requires a substantially increased uranium density in the fuel to offset the decrease in enrichment. Very few fuel phases have been identified that have the required combination of very-high uranium density and stable fuel behavior at high burnup. UMo alloys represent the best known tradeoff in these properties. Testing of aluminum matrix U-Mo aluminum matrix dispersion fuel revealed a pattern of breakaway swelling behavior at intermediate burnup, related to the formation of a molybdenum stabilized high aluminum intermetallic phase that forms during irradiation. In the case of monolithic fuel, this issue was addressed by eliminating, as much as possible, the interfacial area between U-Mo and aluminum. Based on scoping irradiation test data, a fuel plate system composed of solid U-10Mo fuel meat, a zirconium diffusion barrier, and Al6061 cladding was selected for development. Developmental testing of this fuel system indicates that it meets core criteria for fuel qualification, including stable and predictable swelling behavior, mechanical integrity to high burnup, and geometric stability. In addition, the fuel exhibits robust behavior during power-cooling mismatch events under irradiation at high power.

  8. Sono-Electroless Plating of Ni-Mo-P Film

    Science.gov (United States)

    Chiba, Atsushi; Kanou, Masato; Wu, Wen-Chang

    2011-06-01

    Sonication is powerful agitation. Deposited films and electrochemical kinetics parameters were affected. The effects of micro-jet on the deposition rate and shock wave pressure on the smooth of deposited film had been studied. The bath was 0.095 mol/dm3 NiSO46H2O, 0.005 mol/dm3 Na2MoO4, 0.3 mol/dm3 NaH2PO2, 0.06 mol/dm3 Na3C6H5O72H2O, and pH 8.5. The temperature was 353 ± 3 K. The plating rate in sonication had a little faster compared with that in stationary state with micro-jet effects. The thickness of plated film was affected with bath temperature and bath composite. When the concentration ratio of Ni and Mo increased and ratio of Mo was decreased, thickness was thicker. The plated film was an amorphous. Plating rate was faster with micro-jet. The surface was smoothed with shock wave pressures.

  9. Production of Thin Walled Mo Tubing using FBCVD

    Energy Technology Data Exchange (ETDEWEB)

    Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-02

    The goal of this report is to demonstrate our progress towards producing free standing Mo tubing with length up to 12” and wall thickness of 250 µm. Fabrication conditions corresponding to growth of fine grain and high purity Mo material were chosen based on previous work. We focused our effort on execution of prolonged deposition processes and optimization of the FBCVD set up. Our results demonstrated that 12” long Mo tubing can be fabricated by our process. At this point the 12” tube fractured in the middle and resulted in two pieces. Further improvement in one of the fabrication steps will eliminate this drawback. We were not able to produce a tube with 250 µm wall thickness so far. The deposition rate was intentionally kept low (5-6 µm/hr) to form material with fine grain microstructure. Therefore a ~50 hour long deposition run is required to achieve such a wall thickness value, which is quite challenging for the current manually operated FBCVD apparatus. Automation of the set-up is now underway to overcome this problem.

  10. Pore growth in U-Mo/Al dispersion fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeon Soo, E-mail: yskim@anl.gov [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Jeong, G.Y.; Sohn, D.-S. [Ulsan National Institute of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 689-798 (Korea, Republic of); Jamison, L.M. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2016-09-15

    U-Mo/Al dispersion fuel is currently under development in the DOE’s Material Management and Minimization program to convert HEU-fueled research reactors to LEU-fueled reactors. In some demanding conditions in high-power and high-performance reactors, large pores form in the interaction layers between the U-Mo fuel particles and the Al matrix, which pose a potential to cause fuel failure. In this study, comprehension of the formation and growth of these pores was explored. As a product, a model to predict pore growth and porosity increase was developed. The model includes three major topics: fission gas release from the U-Mo and the IL to the pores, stress evolution in the fuel meat, and the effect of amorphous IL growth. Well-characterized in-pile data from reduced-size plates were used to fit the model parameters. A data set from full-sized plates, independent and distinctively different from those used to fit the model parameters, was used to examine the accuracy of the model. The model showed fair agreement with the measured data. The model suggested that the growth of the IL has a critical effect on pore growth, as both its material properties and energetics are favorable to pore formation. Therefore, one area of the current effort, focused on suppressing IL growth, appears to be on the right track to improve the performance of this fuel.

  11. Monolayer MoS{sub 2} self-switching diodes

    Energy Technology Data Exchange (ETDEWEB)

    Al-Dirini, Feras, E-mail: alf@unimelb.edu.au; Hossain, Md Sharafat [Department of Electrical and Electronic Engineering, University of Melbourne, Victoria (Australia); Centre for Neural Engineering, University of Melbourne, Victoria (Australia); Victorian Research Laboratory, National ICT Australia, West Melbourne, Victoria (Australia); Hossain, Faruque M.; Skafidas, Efstratios [Department of Electrical and Electronic Engineering, University of Melbourne, Victoria (Australia); Centre for Neural Engineering, University of Melbourne, Victoria (Australia); Mohammed, Mahmood A. [Princess Sumaya University for Technology, Amman (Jordan); Nirmalathas, Ampalavanapillai [Department of Electrical and Electronic Engineering, University of Melbourne, Victoria (Australia); Melbourne Networked Society Institute (MNSI), University of Melbourne, Victoria (Australia)

    2016-01-28

    This paper presents a new molybdenum disulphide (MoS{sub 2}) nanodevice that acts as a two-terminal field-effect rectifier. The device is an atomically-thin two-dimensional self-switching diode (SSD) that can be realized within a single MoS{sub 2} monolayer with very minimal process steps. Quantum simulation results are presented confirming the device's operation as a diode and showing strong non-linear I-V characteristics. Interestingly, the device shows p-type behavior, in which conduction is dominated by holes as majority charge carriers and the flow of reverse current is enhanced, while the flow of forward current is suppressed, in contrast to monolayer graphene SSDs, which behave as n-type devices. The presence of a large bandgap in monolayer MoS{sub 2} results in strong control over the channel, showing complete channel pinch-off in forward conduction, which was confirmed with transmission pathways plots. The device exhibited large leakage tunnelling current through the insulating trenches, which may have been due to the lack of passivation; nevertheless, reverse current remained to be 6 times higher than forward current, showing strong rectification. The effect of p-type substitutional channel doping of sulphur with phosphorus was investigated and showed that it greatly enhances the performance of the device, increasing the reverse-to-forward current rectification ratio more than an order of magnitude, up to a value of 70.

  12. Interview Jim Pinfold,spokesperson MoEDAL collaboration

    CERN Multimedia

    CERN Audiovisual Productions Service; Noemi Caraban; Paola Catapano; Paola Catapano

    2016-01-01

    Press release Geneva, 10 August 2016. In a paper published by the journal JHEP today, the MoEDAL experiment at CERN[1] narrows the window of where to search for a hypothetical particle, the magnetic monopole. Over the last decades, experiments have been trying to find evidence for magnetic monopoles at accelerators, including at CERN’s Large Hadron Collider. Such particles were first predicted by physicist Paul Dirac in the 1930s but have never been observed so far. “Today MoEDAL celebrates the release of its first physics result and joins the other LHC experiments at the discovery frontier," says Spokesperson of the MoEDAL experiment, James Pinfold. Just as electricity comes with two charges, positive and negative, so magnetism comes with two poles, North and South. The difference is that while it’s easy to isolate a positive or negative electric charge, nobody has ever seen a solitary magnetic charge, or monopole. If you take a bar magnet and cut it in half, you end up with two smaller bar magnets, ea...

  13. Social networks

    CERN Document Server

    Etaner-Uyar, A Sima

    2014-01-01

    The present volume provides a comprehensive resource for practitioners and researchers alike-both those new to the field as well as those who already have some experience. The work covers Social Network Analysis theory and methods with a focus on current applications and case studies applied in various domains such as mobile networks, security, machine learning and health. With the increasing popularity of Web 2.0, social media has become a widely used communication platform. Parallel to this development, Social Network Analysis gained in importance as a research field, while opening up many

  14. Network Warrior

    CERN Document Server

    Donahue, Gary

    2011-01-01

    Pick up where certification exams leave off. With this practical, in-depth guide to the entire network infrastructure, you'll learn how to deal with real Cisco networks, rather than the hypothetical situations presented on exams like the CCNA. Network Warrior takes you step by step through the world of routers, switches, firewalls, and other technologies based on the author's extensive field experience. You'll find new content for MPLS, IPv6, VoIP, and wireless in this completely revised second edition, along with examples of Cisco Nexus 5000 and 7000 switches throughout. Topics include: An

  15. MoVTeNbO multifunctional catalysts: Correlation between constituent crystalline phases and catalytic performance

    Science.gov (United States)

    Botella, P.; García-González, E.; López Nieto, J. M.; González-Calbet, J. M.

    2005-05-01

    The characterization ( S, XPS, XRD, SAED, HREM) and the catalytic performance in the propane oxidation of MoVTeNbO mixed metal oxides catalysts, synthesized by three different preparation procedures, are comparatively presented. Te 2MO 57, Te 0.33MO 3.33 ( M=Mo, V, Nb) and Mo 5O 14-type phases were observed in the most active and selective catalysts. In addition to these, new Te-containing crystalline phases, i.e., MO 47 (cell parameters a=2.16 nm, b=1.96 nm and c=0.39 nm) and an unidentified phase deriving from the tetragonal tungsten bronze (TTB) type structure with cell parameters a=√{2}a and c=c, have also been observed in samples prepared from a slurry containing vanadyl sulphate, although they presented a low catalytic activity. The catalytic performance of MoVTeNbO multifunctional catalysts is related to the presence of Te 2MO 57-type phase ( M=Mo, V, and Nb), although cooperation between phases must also exist. However, a certain composition or composition range is necessary to achieve the best catalytic performance, since the chemical composition of Te 2MO 57-type phase changes in every catalyst. Te 2MO 57-type phase with a Te 0.32(Mo 0.79Nb 0.11V 0.10) 5O 14 composition has been found in the most active and selective catalyst whereas Te 0.6(Mo 0.72Nb 0.14V 0.13) 5O 14 is the constituent in the less active and selective one, the rest of the catalysts presenting intermediate both Te/Mo ratio and catalytic performance.

  16. Electrochemical Hydrogen Evolution at Ordered Mo 7 Ni 7

    Energy Technology Data Exchange (ETDEWEB)

    Csernica, Peter M. [Department; McKone, James R. [Department; Mulzer, Catherine R. [Dow Electronic Materials, Marlborough Massachusetts 01752, United States; Dichtel, William R. [Department; Abruña, Héctor D. [Department; DiSalvo, Francis J. [Department

    2017-04-11

    Ni–Mo alloys containing up to ~15 mol % Mo are excellent non-noble electrocatalysts for the hydrogen evolution reaction (HER) in alkaline aqueous electrolytes. To date, studies have not addressed the details of HER activity of ordered Ni–Mo intermetallic compounds, which can contain a significantly larger fraction of Mo (up to 50 mol %) than can be accessed through high-temperature alloying. Here, we present a straightforward and facile synthesis of three phase-pure electrocatalyst powders using a precipitation–reduction approach: ordered Mo7Ni7, disordered Ni0.92Mo0.08, and pure Ni. The Ni0.92Mo0.08 alloy exhibited a nearly 10-fold higher mass-specific HER activity than either pure Ni or Mo7Ni7, where much of the difference could be attributed to relative surface area. Therefore, we attempted to quantify and account for differences in surface areas using electron microscopy, impedance spectroscopy, and gas adsorption measurements. These data suggest that Ni–Mo alloys and intermetallic compounds exhibit substantial pseudocapacitance at potentials near the onset of hydrogen evolution, which can cause impedance spectroscopy to overestimate the interfacial capacitance, and thus the electrochemically active surface area, of these materials. From these observations, we postulate Mo redox activity as the chemical basis for the observed pseudocapacitance of Ni–Mo composites. Furthermore, using gas adsorption measurements, rather than capacitance, to estimate active surface area, we find that ordered Mo7Ni7 is more intrinsically active than the Ni0.92Mo0.08 alloy, implying that Mo7Ni7 intermetallics with high surface area will also give higher mass-specific activities than alloys with comparable roughness.

  17. High-Performance Photovoltaic Detector Based on MoTe2/MoS2Van der Waals Heterostructure.

    Science.gov (United States)

    Chen, Yan; Wang, Xudong; Wu, Guangjian; Wang, Zhen; Fang, Hehai; Lin, Tie; Sun, Shuo; Shen, Hong; Hu, Weida; Wang, Jianlu; Sun, Jinglan; Meng, Xiangjian; Chu, Junhao

    2018-01-22

    Van der Waals heterostructures based on 2D layered materials have received wide attention for their multiple applications in optoelectronic devices, such as solar cells, light-emitting devices, and photodiodes. In this work, high-performance photovoltaic photodetectors based on MoTe 2 /MoS 2 vertical heterojunctions are demonstrated by exfoliating-restacking approach. The fundamental electric properties and band structures of the junction are revealed and analyzed. It is shown that this kind of photodetectors can operate under zero bias with high on/off ratio (>10 5 ) and ultralow dark current (≈3 pA). Moreover, a fast response time of 60 µs and high photoresponsivity of 46 mA W -1 are also attained at room temperature. The junctions based on 2D materials are expected to constitute the ultimate functional elements of nanoscale electronic and optoelectronic applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Managing Networks

    DEFF Research Database (Denmark)

    Jørgensen, Heidi; Vintergaard, Christian

    Logically it seems that companies pursuing different business strategies wouldalso manage their relationships with other firms accordingly. Nevertheless, due tothe lack of research in the field of network strategies, this link still remainsinadequately examined. Based on the well-known framework...... isprovided, that the relation between a company's strategy, structure and processesin fact have a considerable influence on its pattern of network behaviour. Threecase studies from the Danish biotech industry exemplify and illustrate how acompany's strategy is directly correlated with how it manages its...... of organisationalbehaviour developed by Miles and Snow (1978), this paper argues that thepatterns of network behaviour practiced by firms greatly depend on the businesstypology of the company. That is, a company's business typology will to a certaindegree dictate the network identity of the company. In this paper evidence...

  19. Heterodox networks

    DEFF Research Database (Denmark)

    Lala, Purnima; Kumar, Ambuj

    2016-01-01

    architecture of ‘Hovering Ad-hoc Network (HANET)’ for the latter will be deployed to assist and manage the overloaded primary base stations enhancing the on-demand coverage and capacity of the entire system. Proposed modes can either operate independently or as a cascaded architecture to form a Heterodox......It is imperative for the service providers to bring innovation in the network design to meet the exponential growth of mobile subscribers for multi-technology future wireless networks. As a matter of research, studies on providing services to moving subscriber groups aka ‘Place Time Capacity (PTC......)’ have not been considered much in the literature. In this article we present Heterodox networks as an innovative and alternate approach to handle the PTC congestion. We describe two different approaches to combat the PTC congestion where the traditional terrestrial infrastructure fails to provide...

  20. Exchange Network

    Science.gov (United States)

    The Environmental Information Exchange Network (EIEN) is an Internet-based system used by state, tribal and territorial partners to securely share environmental and health information with one another and EPA.

  1. Sentinel Network

    Science.gov (United States)

    The Sentinel Network is an integrated, electronic, national medical product safety initiative that compiles information about the safe and effective use of medical products accessible to patients and healthcare practitioners.

  2. computer networks

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2002-01-01

    Full Text Available In this paper, we construct a new dynamic model for the Token Bucket (TB algorithm used in computer networks and use systems approach for its analysis. This model is then augmented by adding a dynamic model for a multiplexor at an access node where the TB exercises a policing function. In the model, traffic policing, multiplexing and network utilization are formally defined. Based on the model, we study such issues as (quality of service QoS, traffic sizing and network dimensioning. Also we propose an algorithm using feedback control to improve QoS and network utilization. Applying MPEG video traces as the input traffic to the model, we verify the usefulness and effectiveness of our model.

  3. Validating module network learning algorithms using simulated data.

    Science.gov (United States)

    Michoel, Tom; Maere, Steven; Bonnet, Eric; Joshi, Anagha; Saeys, Yvan; Van den Bulcke, Tim; Van Leemput, Koenraad; van Remortel, Piet; Kuiper, Martin; Marchal, Kathleen; Van de Peer, Yves

    2007-05-03

    In recent years, several authors have used probabilistic graphical models to learn expression modules and their regulatory programs from gene expression data. Despite the demonstrated success of such algorithms in uncovering biologically relevant regulatory relations, further developments in the area are hampered by a lack of tools to compare the performance of alternative module network learning strategies. Here, we demonstrate the use of the synthetic data generator SynTReN for the purpose of testing and comparing module network learning algorithms. We introduce a software package for learning module networks, called LeMoNe, which incorporates a novel strategy for learning regulatory programs. Novelties include the use of a bottom-up Bayesian hierarchical clustering to construct the regulatory programs, and the use of a conditional entropy measure to assign regulators to the regulation program nodes. Using SynTReN data, we test the performance of LeMoNe in a completely controlled situation and assess the effect of the methodological changes we made with respect to an existing software package, namely Genomica. Additionally, we assess the effect of various parameters, such as the size of the data set and the amount of noise, on the inference performance. Overall, application of Genomica and LeMoNe to simulated data sets gave comparable results. However, LeMoNe offers some advantages, one of them being that the learning process is considerably faster for larger data sets. Additionally, we show that the location of the regulators in the LeMoNe regulation programs and their conditional entropy may be used to prioritize regulators for functional validation, and that the combination of the bottom-up clustering strategy with the conditional entropy-based assignment of regulators improves the handling of missing or hidden regulators. We show that data simulators such as SynTReN are very well suited for the purpose of developing, testing and improving module network

  4. Synthesis and characterization of Ni-Mo filler brazing alloy for Mo-W joining for microwave tube technology

    Directory of Open Access Journals (Sweden)

    Frank Ferrer Sene

    2013-04-01

    Full Text Available A brazing process based on Ni-Mo alloy was developed to join porous tungsten cathode bottom and dense molybdenum cathode body for microwave tubes manufacture. The Ni-Mo alloy was obtained by mixing and milling powders in the eutectic composition, and applied on the surface of the components. The brazing was made at 1400 °C by using induction heating in hydrogen for 5 minutes. Alumina surfaces were coated with the binder and analyzed by Energy Dispersive X-rays Fluorescence. The brazed samples were analyzed by Scanning Electron Microscopy coupled to Energy Dispersive Spectroscopy. Stress-strain tests were performed to determine the mechanical behavior of the joining. The quality of the brazing was evaluated by assuring the presence of a "meniscus" formed by the Ni-Mo alloy on the border of the tungsten and molybdenum joint, the absence of microstructural defects in the interface between the tungsten and molybdenum alloys, and the adhesion of the brazed components.

  5. G4MoNA - A Geant4 Simulation for unbound nuclides detected with MoNA/LISA

    Science.gov (United States)

    Gueye, Paul; Freeman, Jessica; Frank, Nathan; MoNA Collaboration

    2017-01-01

    The MoNA Collaboration has conducted a plethora of experiments to study unbound nuclei near the neutron dripline using the invariant mass technique since 2005. These experiments used a variety of secondary beams from the Coupled Cyclotron Facility of the National Superconducting Cyclotron Laboratory. The experimental setup consists of a large gap superconducting Sweeper magnet for charged fragments separation and the MoNA/LISA neutron detector arrays for neutron detection. Recently, a multi-layered Si/Be segmented target consisting of three 700 mg/cm2 thick 9Be slabs and four 140 μ m Si detectors were added to the setup. This target improves the resolution of the reconstructed decay energy spectra of the unbound nuclides. The Geant4 Monte Carlo simulation toolkit was used to develop a complete realistic model of the setup including a new class to treat the decay of unbound nuclei, the Si/Be segmented target, the MoNA/LISA and the charged fragments detector systems. Comparison between simulated and experimental data will be presented. DoENNSA - DE-NA0000979.

  6. Affective Networks

    Directory of Open Access Journals (Sweden)

    Jodi Dean

    2010-02-01

    Full Text Available This article sets out the idea of affective networks as a constitutive feature of communicative capitalism. It explores the circulation of intensities in contemporary information and communication networks, arguing that this circulation should be theorized in terms of the psychoanalytic notion of the drive. The article includes critical engagements with theorists such as Guy Debord, Jacques Lacan, Tiziana Terranova, and Slavoj Zizek.

  7. Friendship Networks

    OpenAIRE

    Jan K. Brueckner

    2004-01-01

    Building upon a long tradition in sociology, economists have recently turned their attention to the analysis of social networks. The present paper adds to this emerging literature by proposing a different approach to social-network formation. As in the model of Jackson and Wolinsky (1996), formation of a link between two individuals requires two-sided investments in the present framework. But in contrast to their approach, where the required investments are exogenously specified and link form...

  8. Developer Network

    Energy Technology Data Exchange (ETDEWEB)

    2012-08-21

    NREL's Developer Network, developer.nrel.gov, provides data that users can access to provide data to their own analyses, mobile and web applications. Developers can retrieve the data through a Web services API (application programming interface). The Developer Network handles overhead of serving up web services such as key management, authentication, analytics, reporting, documentation standards, and throttling in a common architecture, while allowing web services and APIs to be maintained and managed independently.

  9. Network Power Fault Detection

    OpenAIRE

    Siviero, Claudio

    2013-01-01

    Network power fault detection. At least one first network device is instructed to temporarily disconnect from a power supply path of a network, and at least one characteristic of the power supply path of the network is measured at a second network device connected to the network while the at least one first network device is temporarily disconnected from the network

  10. Complex Networks

    CERN Document Server

    Evsukoff, Alexandre; González, Marta

    2013-01-01

    In the last decade we have seen the emergence of a new inter-disciplinary field focusing on the understanding of networks which are dynamic, large, open, and have a structure sometimes called random-biased. The field of Complex Networks is helping us better understand many complex phenomena such as the spread of  deseases, protein interactions, social relationships, to name but a few. Studies in Complex Networks are gaining attention due to some major scientific breakthroughs proposed by network scientists helping us understand and model interactions contained in large datasets. In fact, if we could point to one event leading to the widespread use of complex network analysis is the availability of online databases. Theories of Random Graphs from Erdös and Rényi from the late 1950s led us to believe that most networks had random characteristics. The work on large online datasets told us otherwise. Starting with the work of Barabási and Albert as well as Watts and Strogatz in the late 1990s, we now know th...

  11. Sentient networks

    Energy Technology Data Exchange (ETDEWEB)

    Chapline, G.

    1998-03-01

    The engineering problems of constructing autonomous networks of sensors and data processors that can provide alerts for dangerous situations provide a new context for debating the question whether man-made systems can emulate the cognitive capabilities of the mammalian brain. In this paper we consider the question whether a distributed network of sensors and data processors can form ``perceptions`` based on sensory data. Because sensory data can have exponentially many explanations, the use of a central data processor to analyze the outputs from a large ensemble of sensors will in general introduce unacceptable latencies for responding to dangerous situations. A better idea is to use a distributed ``Helmholtz machine`` architecture in which the sensors are connected to a network of simple processors, and the collective state of the network as a whole provides an explanation for the sensory data. In general communication within such a network will require time division multiplexing, which opens the door to the possibility that with certain refinements to the Helmholtz machine architecture it may be possible to build sensor networks that exhibit a form of artificial consciousness.

  12. Influence of inserted Mo layer on the thermal stability of perpendicularly magnetized Ta/Mo/Co20Fe60B20/MgO/Ta films

    Directory of Open Access Journals (Sweden)

    Minghua Li

    2016-04-01

    Full Text Available We studied the thermal stability of perpendicular magnetic anisotropy (PMA in Ta/Mo/CoFeB/MgO/Ta films with and without inserted Mo layers. In the absence of a Mo layer, the films show PMA at annealing temperatures below 300 °C. On the other hand, the insertion of a Mo layer preserves PMA at annealing temperatures of up to 500 °C; however, a higher annealing temperature leads to the collapse of PMA. X-ray photoelectron spectroscopy (XPS and high-resolution transmission electron microscopy (HRTEM were used to study the microstructure of the films to understand the deterioration of PMA. The XPS results show that the segregation of Ta is partly suppressed by inserting a Mo layer. Once inserted, Mo does not remain at the interface of Ta and CoFeB but migrates to the surface of the films. The HRTEM results show that the crystallization of the MgO (001 texture is improved owing to the higher annealing temperature of the Mo inserted sample. A smooth and clear CoFeB/MgO interface is evident. The inserted Mo layer not only helps to obtain sharper and smoother interfaces but also contributes to the crystallization after the higher annealing temperature of films.

  13. Design of a Fission 99 Mo Recovery Process and Implications toward Mo Adsorption Mechanism on Titania and Alumina Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Stepinski, Dominique C.; Youker, Amanda J.; Krahn, Elizabeth O.; Vandegrift, George F.; Chung, Pei-Lun; Wang, Nien-Hwa Linda

    2017-03-01

    Molybdenum-99 is a parent of the most widely used medical isotope technetium-99m. Proliferation concerns have prompted development of alternative Mo production methods utilizing low enriched uranium. Alumina and titania sorbents were evaluated for separation of Mo from concentrated uranyl nitrate solutions. System, mass transfer, and isotherm parameters were determined to enable design of Mo separation processes under a wide range of conditions. A model-based approach was utilized to design representative commercial-scale column processes. The designs and parameters were verified with bench-scale experiments. The results are essential for design of Mo separation processes from irradiated uranium solutions, selection of support material and process optimization. Mo uptake studies show that adsorption decreases with increasing concentration of uranyl nitrate; howeveL, examination of Mo adsorption as a function of nitrate ion concentration shows no dependency, indicating that uranium competes with Mo for adsorption sites. These results are consistent with reports indicating that Mo forms inner-sphere complexes with titania and alumina surface groups.

  14. Single Phase Melt Processed Powellite (Ba,Ca) MoO{sub 4} For The Immobilization Of Mo-Rich Nuclear Waste

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, Kyle [Savannah River Site (SRS), Aiken, SC (United States); Marra, James [Savannah River Site (SRS), Aiken, SC (United States); Fox, Kevin [Savannah River Site (SRS), Aiken, SC (United States); Reppert, Jason [Savannah River Site (SRS), Aiken, SC (United States); Crum, Jarrod [Paci fic Northwest National Laboratory , Richland, WA (United States); Tang, Ming [Los Alamos National Laboratory , Los Alamos, NM (United States)

    2012-09-17

    Crystalline and glass composite materials are currently being investigated for the immobilization of combined High Level Waste (HLW) streams resulting from potential commercial fuel reprocessing scenarios. Several of these potential waste streams contain elevated levels of transition metal elements such as molybdenum (Mo). Molybdenum has limited solubility in typical silicate glasses used for nuclear waste immobilization. Under certain chemical and controlled cooling conditions, a powellite (Ba,Ca)MoO{sub 4} crystalline structure can be formed by reaction with alkaline earth elements. In this study, single phase BaMoO{sub 4} and CaMoO{sub 4} were formed from carbonate and oxide precursors demonstrating the viability of Mo incorporation into glass, crystalline or glass composite materials by a melt and crystallization process. X-ray diffraction, photoluminescence, and Raman spectroscopy indicated a long range ordered crystalline structure. In-situ electron irradiation studies indicated that both CaMoO{sub 4} and BaMoO{sub 4} powellite phases exhibit radiation stability up to 1000 years at anticipated doses with a crystalline to amorphous transition observed after 1 X 10{sup 13} Gy. Aqueous durability determined from product consistency tests (PCT) showed low normalized release rates for Ba, Ca, and Mo (<0.05 g/m{sup 2}).

  15. Growth and characteristics of self-assembled MoS2/Mo-S-C nanoperiod multilayers for enhanced tribological performance

    Science.gov (United States)

    Xu, Jiao; He, TengFei; Chai, LiQiang; Qiao, Li; Wang, Peng; Liu, WeiMin

    2016-01-01

    Highly ordered MoS2/Mo-S-C nanoperiod multilayers are synthesized by a novel self-assembling mechanism in simultaneous sputtering of MoS2 and graphite targets. The sequential formation of MoS2-riched domain layers and Mo-S-C compositional mixed capping layers reveals no correspondence to the sample stage rotation but is caused by the low energy ion bombardment enhanced interdiffusion. The HRTEM observation shows that the phase segregation normal to the film surface is initiated from substrate-film interlayer with clear contrasts in the first few bi-layers, and then diffuses mutually in a quasiperiodic pattern between two altered sub-layers. Compared with sputtered MoS2 film, the bulk film of multilayers exhibit largely improved toughness under a normal load, and the preferential orientation of sputtered MoS2 in (002) basal planes is significantly enhanced, both of which render the film excellent loads-bearing capacity and lubricant properties. The nano-scratching tests performed on a nanoindentation system suggest that the nano-tribological performance of multilayers is directly determined by the altered structure and properties of neighboring sub-layers until stable tribofilms are formed. Meanwhile, the pin-on-disk tribotests in ambient air, low vacuum and high vacuum provide comparably low friction coefficient yet distinct wear lives in different atmospheres due to the partially restricted humid-sensitivity of sputtered MoS2 phase. PMID:27137707

  16. Low sub-threshold swing realization with contacts of graphene/h-BN/MoS2 heterostructures in MoS2 transistors

    Science.gov (United States)

    Li, Chao; Yan, Xiao; Bao, Wenzhong; Ding, Shijin; Zhang, David Wei; Zhou, Peng

    2017-11-01

    MoS2 and other atomically thin-layered semiconductors have attracted intensive interest for their unique characteristics and have become promising candidates for short-channel transistor devices. In this work, we demonstrate an MoS2 transistor with a graphene/hBN/MoS2 heterostructure contact so as to achieve a low sub-threshold swing (SS) and expand the scope of the drain current with a low SS. By inserting an h-BN tunneling layer between graphene and MoS2, the carrier transport with a tunneling effect across h-BN makes the transistor exhibit a less than 80 mV/dec sub-threshold swing over 4 orders of magnitude of the drain current at room temperature. Meanwhile, the MoS2 transistor achieves a maximum on/off ratio of ˜107, and the heterostructure contact shows fairly good ohmic characteristics. Furthermore, the thickness of the h-BN tunneling layer in the heterostructure is optimized, which is essential for the tunneling current and the performance of an MoS2 transistor. This study of an MoS2 transistor based on a graphene/h-BN/MoS2 heterostructure contact may pave the way for the development of thin-layered semiconductors in low-power electronic applications.

  17. Influence of Mo/MoSe2 microstructure on the damp heat stability of the Cu(In,Ga)Se2 back contact molybdenum

    NARCIS (Netherlands)

    Theelen, M.; Harel, S.; Verschuren, M.; Tomassini, M.; Hovestad, A.; Barreau, N.; Berkum, J. van; Vroon, Z.; Zeman, M.

    2015-01-01

    The degradation behavior of Mo/MoSe2 layers have been investigated using damp heat exposure. The two studied molybdenum based films with different densities and microstructures were obtained by lifting off Cu(In,Ga)Se2 layers froma bilayer molybdenum stack on soda lime glass. Hereby, a

  18. Electric vehicle integration into modern power networks

    CERN Document Server

    Garcia-Valle, Rodrigo

    2012-01-01

    Electric Vehicle Integration into Modern Power Networks provides coverage of the challenges and opportunities posed by the progressive integration of electric drive vehicles. Starting with a thorough overview of the current electric vehicle and battery state-of-the-art, this work describes dynamic software tools to assess the impacts resulting from the electric vehicles deployment on the steady state and dynamic operation of electricity grids, identifies strategies to mitigate them and the possibility to support simultaneously large-scale integration of renewable energy sources.New business mo

  19. Characterization of electrical resistivity as a function of temperature in the Mo-Si-B system

    Energy Technology Data Exchange (ETDEWEB)

    Beckman, Sarah E. [Iowa State Univ., Ames, IA (United States)

    1999-12-10

    Measurements of electrical resistivity as a function of temperature from 25 to 1,500 C were conducted on polycrystalline samples in the Mo-Si-B system. Single phase, or nearly single phase, samples were prepared for the following phases: Mo3Si, Mo5SiB2, Mo5Si3Bx, MoB, MoSi2, and Mo5Si3. Thesis materials all exhibit resistivity values within a narrow range(4--22 x 10-7Ω-m), and the low magnitude suggests these materials are semi-metals or low density of states metals. With the exception of MoSi2, all single phase materials in this study were also found to have low temperature coefficient of resistivity(TCR) values. These values ranged from 2.10 x 10-10 to 4.74 x 10-10Ω-m/° C, and MoSi2 had a TCR of 13.77 x 10-10Ω-m/° C. The results from the single phase sample measurements were employed in a natural log rule-of-mixtures model to relate the individual phase resistivity values to those of multiphase composites. Three Mo-Si-B phase regions were analyzed: the binary Mo5Si3-MoSi2 system, the ternary phase field Mo5Si3BxMoB-MoSi2, and the Mo3Si-Mo5SiB2-Mo5Si3Bx ternary region. The experimental data for samples in each of these regions agreed with the natural log model and illustrated that this model can predict the electrical resistivity as a function of temperature of multi-phase, sintered samples within an error of one standard deviation.

  20. Phase transitions during artificial ageing of segregated as-cast U–Mo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa, Tércio Assunção, E-mail: tap@cdtn.br [CDTN/CNEN, Centro de Desenvolvimento da Tecnologia Nuclear, Av. Presidente Antônio Carlos, 6627 31270-901 Belo Horizonte, MG (Brazil); Santos, Ana Maria Matildes dos; Soares Lameiras, Fernando [CDTN/CNEN, Centro de Desenvolvimento da Tecnologia Nuclear, Av. Presidente Antônio Carlos, 6627 31270-901 Belo Horizonte, MG (Brazil); Cetlin, Paulo Roberto [Departamento de Engenharia Mecânica, Universidade Federal de Minas Gerais, Av. Presidente Antônio Carlos, 6627 31270-901 Belo Horizonte, MG (Brazil); Ferraz, Wilmar Barbosa [CDTN/CNEN, Centro de Desenvolvimento da Tecnologia Nuclear, Av. Presidente Antônio Carlos, 6627 31270-901 Belo Horizonte, MG (Brazil)

    2015-02-15

    Highlights: • Phase transitions during ageing were investigated in segregated as-cast U–5/7/10Mo alloys. • As-cast structures with α and γ variants were found for the full 4–12 wt.% Mo range. • Low temperature ageing resulted in twinning (<6.5 wt.% Mo) and disorder-ordering reaction (4.0–8.5 wt.% Mo). • At 500 °C, NL (<6.5 wt.% Mo) and L (6.5–8.5 wt.% Mo) arrangements of α + γ′ phases were found. • Acicular γ′ marked the onset of the γ decomposition in the two highest Mo ranges, from 8.5 to 12.0 wt.%. - Abstract: U–Mo alloys are a promising alternative in high-density fuel materials for use in research and test reactors, due to its resistance to swelling associated with the presence of the metastable γ-phase in the microstructure. It has been reported that increasing additions of Mo cause a beneficial delay in the decomposition of the γ-phase in U–Mo alloys during isothermal heat treatments. Analyses emphasized high temperature aging (>400 °C), where the microstructural evolution features were followed by low resolution light microcopy, but little information is available for lower temperature treatments. High resolution microstructural characterization techniques allow a more in depth analysis of the decomposition, as already shown for U–Nb alloys. In this work, phase transitions resulting from the decomposition of the γ-phase, or its variants, were investigated in as-cast U–Mo alloys with 5, 7 and 10 wt.% Mo, aged at 300 and 500 °C. Characterization techniques employed light microscopy, hardness, high resolution FE-SEM and EFM, which establishes contrasts for domains with different physical properties. The ageing of Mo-segregated regions, typical of the as-cast state, allowed the consideration of a broad range of Mo contents. For the low Mo regions, results were similar to those reported for U–Nb alloys, involving transformation twins and disorder-ordering mechanisms in the low temperature ageing and the formation of a

  1. Evidence for semileptonic B<mo>- stretchy='false'>→mo>pp<mo stretchy='false'>¯mo><mo>ℓmo>->ν<mo stretchy='false'>¯mo><mo>ℓ> decays

    Energy Technology Data Exchange (ETDEWEB)

    Tien, K. -J.; Wang, M. -Z.; Adachi, I.; Aihara, H.; Asner, D. M.; Aulchenko, V.; Aushev, T.; Bakich, A. M.; Bala, A.; Bhuyan, B.; Bozek, A.; Bračko, M.; Browder, T. E.; Chang, P.; Chekelian, V.; Chen, A.; Chen, P.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, I. -S.; Cho, K.; Chobanova, V.; Choi, Y.; Cinabro, D.; Dalseno, J.; Danilov, M.; Doležal, Z.; Drásal, Z.; Dutta, D.; Eidelman, S.; Farhat, H.; Fast, J. E.; Ferber, T.; Gaur, V.; Ganguly, S.; Gillard, R.; Goh, Y. M.; Golob, B.; Haba, J.; Hayashii, H.; Horii, Y.; Hoshi, Y.; Hou, W. -S.; Hsiung, Y. B.; Huschle, M.; Hyun, H. J.; Iijima, T.; Ishikawa, A.; Itoh, R.; Iwasaki, Y.; Julius, T.; Kah, D. H.; Kang, J. H.; Kato, E.; Kawasaki, T.; Kichimi, H.; Kiesling, C.; Kim, D. Y.; Kim, H. J.; Kim, J. B.; Kim, J. H.; Kim, Y. J.; Klucar, J.; Ko, B. R.; Kodyš, P.; Korpar, S.; Križan, P.; Krokovny, P.; Kronenbitter, B.; Kuhr, T.; Kumita, T.; Kuzmin, A.; Kwon, Y. -J.; Lee, S. -H.; Li, J.; Li, Y.; Libby, J.; Liu, C.; Liu, Y.; Liventsev, D.; Lukin, P.; Miyabayashi, K.; Miyata, H.; Mohanty, G. B.; Moll, A.; Mussa, R.; Nakano, E.; Nakao, M.; Natkaniec, Z.; Nayak, M.; Nedelkovska, E.; Ng, C.; Nisar, N. K.; Nishida, S.; Nitoh, O.; Ogawa, S.; Okuno, S.; Olsen, S. L.; Ostrowicz, W.; Oswald, C.; Park, C. W.; Park, H.; Park, H. K.; Pedlar, T. K.; Pestotnik, R.; Petrič, M.; Piilonen, L. E.; Ritter, M.; Röhrken, M.; Rostomyan, A.; Sahoo, H.; Saito, T.; Sakai, Y.; Sandilya, S.; Santel, D.; Santelj, L.; Sanuki, T.; Sato, Y.; Savinov, V.; Schneider, O.; Schnell, G.; Schwanda, C.; Semmler, D.; Senyo, K.; Seon, O.; Sevior, M. E.; Shapkin, M.; Shen, C. P.; Shibata, T. -A.; Shiu, J. -G.; Sibidanov, A.; Sohn, Y. -S.; Sokolov, A.; Stanič, S.; Starič, M.; Steder, M.; Sumihama, M.; Sumiyoshi, T.; Tanida, K.; Tatishvili, G.; Teramoto, Y.; Uchida, M.; Uehara, S.; Uglov, T.; Unno, Y.; Uno, S.; Urquijo, P.; Vahsen, S. E.; Van Hulse, C.; Vanhoefer, P.; Varner, G.; Varvell, K. E.; Vinokurova, A.; Vorobyev, V.; Wagner, M. N.; Wang, C. H.; Wang, P.; Watanabe, M.; Watanabe, Y.; Williams, K. M.; Won, E.; Yamaoka, J.; Yamashita, Y.; Yashchenko, S.; Zhang, Z. P.; Zhilich, V.; Zhulanov, V.; Zupanc, A.

    2014-01-01

    We find evidence for the semileptonic baryonic decay B-→pp¯ℓ-ν¯ℓ (ℓ=e, μ), based on a data sample of 772 million BB¯ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy electron-positron collider. A neural-network based hadronic B-meson tagging method is used in this study. The branching fraction of B-→pp¯ℓ-ν¯ℓ is measured to be (5.8+2.4-2.1(stat)±0.9(syst))×10-6 with a significance of 3.2σ, where lepton universality is assumed. We also estimate the corresponding upper limit: B(B-→pp¯ℓ-ν¯ℓ)<9.6×10-6 at the 90% confidence level. This measurement helps constrain the baryonic transition form factor in B decays

  2. Porous metallic MoO2-supported MoS2 nanosheets for enhanced electrocatalytic activity in the hydrogen evolution reaction

    Science.gov (United States)

    Yang, Linjing; Zhou, Weijia; Hou, Dongman; Zhou, Kai; Li, Guoqiang; Tang, Zhenghua; Li, Ligui; Chen, Shaowei

    2015-03-01

    Advanced materials for electrocatalytic water splitting are central to renewable energy research. In this work, MoS2 nanosheets supported on porous metallic MoO2 (MoS2/MoO2) were produced by sulfuration treatments of porous and highly conductive MoO2 for the hydrogen evolution reaction. Porous MoO2 with one-dimensional channel-like structures was prepared by calcination at elevated temperatures using phosphomolybdic acid as the precursor and mesoporous silica (SBA-15) as the template, and the subsequent hydrothermal treatment in the presence of thioacetamide led to the transformation of the top layers to MoS2 forming MoS2/MoO2 composites. Electrochemical studies showed that the obtained composites exhibited excellent electrocatalytic activity for HER with an onset potential of -104 mV (vs. RHE), a large current density (10 mA cm-2 at -0.24 V), a small Tafel slope of 76.1 mV dec-1 and robust electrochemical durability. The performance might be ascribed to the high electrical conductivity and porous structures of MoO2 with one-dimensional channels of 3 to 4 nm in diameter that allowed for fast charge transport and collection.Advanced materials for electrocatalytic water splitting are central to renewable energy research. In this work, MoS2 nanosheets supported on porous metallic MoO2 (MoS2/MoO2) were produced by sulfuration treatments of porous and highly conductive MoO2 for the hydrogen evolution reaction. Porous MoO2 with one-dimensional channel-like structures was prepared by calcination at elevated temperatures using phosphomolybdic acid as the precursor and mesoporous silica (SBA-15) as the template, and the subsequent hydrothermal treatment in the presence of thioacetamide led to the transformation of the top layers to MoS2 forming MoS2/MoO2 composites. Electrochemical studies showed that the obtained composites exhibited excellent electrocatalytic activity for HER with an onset potential of -104 mV (vs. RHE), a large current density (10 mA cm-2 at -0.24 V), a

  3. Novel Approach to the Fabrication of an Alumina-MoS2 Self-Lubricating Composite via the In Situ Synthesis of Nanosized MoS2.

    Science.gov (United States)

    Su, Yunfeng; Zhang, Yongsheng; Song, Junjie; Hu, Litian

    2017-09-13

    The fabrication of a self-lubricating ceramic composite with MoS2 as the solid lubricant is extremely difficult given the high temperature sensitivity of MoS2. In this study, a hydrothermal method was utilized for the in situ synthesis of nanosized-MoS2 in Al2O3 ceramic to fabricate an Al2O3-MoS2 self-lubricating composite. The composite exhibited excellent self-lubricating properties with low friction coefficient and wear rate in a high-vacuum environment because of the efficient formation of self-lubricating films from the finely structured MoS2 in the Al2O3 matrix. The results of this study establish a new approach to the fabrication of self-lubricating ceramic composites with temperature-sensitive solid lubricants.

  4. Facile and low cost oxidative conversion of MoS2 in α-MoO3: Synthesis, characterization and application

    Science.gov (United States)

    Bortoti, Andressa Antunes; Gavanski, Amanda de Freitas; Velazquez, Yegraf Reyna; Galli, Andressa; de Castro, Eryza Guimarães

    2017-08-01

    This study describes a facile low cost route to synthesize the α-MoO3 through a conversion of the precursor MoS2 in oxidant media. The structure and morphology of the α-MoO3 were studied by high resolution transmission electron microscopy (HRTEM) and selected area electron diffraction (SAED), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The results show that α-MoO3 was obtained with reduced size, high purity, strongly-preferred orientation and structural defects, which ensures versatility and multifunctionality to this sample. For the purpose of applications, α-MoO3 was successfully employed in inverted organic solar cells devices as a possible alternative to the PEDOT:PSS in the hole transportation layer.

  5. Influence of chemical composition in crystallographic texture Fe-Cr-Mo alloys; Influencia da composicao quimica na textura cristalografica de ligas Fe-Cr-Mo

    Energy Technology Data Exchange (ETDEWEB)

    Moura, L.B.; Guimaraes, R.F. [Instituto Federal de Educacao, Ciencia e Tecnologia do Ceara, Fortaleza, CE (Brazil). Dept. da Industria; Abreu, H.F.G. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil)

    2010-07-01

    The use of steels with higher contents of Mo in the oil industry has been an alternative to reduce the effect of naphthenic corrosion in refining units. The addition of Mo in Fe-Cr alloys in the same manner that increases resistance to corrosion naphthenic causes some difficulties such as difficulty of forming, welding and embrittlement. In this work, experimental ingots of Fe-Cr-Mo alloys (Cr - 9, 15 and 17%, Mo - 5, 7 and 9%) were melted in vacuum induction furnace and hot and cold rolled in a laboratory rolling mill. The influence of chemical composition on crystallographic texture of samples subjected to the same thermo-mechanical treatment was analyzed by x-ray diffraction. The results indicate that fiber (111) becomes more intense with increasing Mo and/or Cr contents. (author)

  6. Relevance of the Mo-precursor state in H-ZSM-5 for methane dehydroaromatization

    KAUST Repository

    Vollmer, Ina

    2018-01-04

    Although the local geometry of Mo in Mo/HZSM-5 has been characterized before, we present a systematic way to manipulate the configuration of Mo and link it to its catalytic properties. The location and geometry of cationic Mo-complexes, the precursor of the active metal site for methane dehydroaromatization, are altered by directing the way they anchor to the framework of the zeolite. The feature used to direct the anchoring of Mo is the location of Al in the zeolite framework. According to DFT calculations, the local geometry of Mo should change, while UV-vis and pyridine FTIR spectroscopy indicated differences in the dispersion of Mo. Both aspects, however, did not influence the catalytic behavior of Mo/HZSM-5, indicating that as long as enough isolated Mo species are present inside the pores of the zeolite, the catalytic behavior is unaffected. This paves the way to better understand how the Mo oxo precursor transforms into the active phase under the reaction conditions.

  7. Interdiffusion studies on hot rolled U-10Mo/AA1050

    Energy Technology Data Exchange (ETDEWEB)

    Saliba-Silva, A.M.; Martins, I.C.; Carvalho, E.U.; Durazzo, M.; Riella, H.G. [Instituto de Pesquisas Energeticas e Nucleares (CCN/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Combustivel Nuclear], e-mail: saliba@ipen.br

    2010-07-01

    The U-Mo alloys are investigated with the goal of becoming nuclear material to fabricate high-density fuel elements for high performance research reactors. This enrichment level suggests that the U-Mo alloys should be between 6 to 10wt%, which can give up to 9gU/cm{sup 3} as fuel density. Nevertheless, the U-Mo alloys are very reactive with Al. Interdiffusion reaction products are formed since nuclear fission promotes chemical interaction layer during operation, leading to potential structural failure. Present studies were made with treated hot rolled diffusion couples of U-10Mo inserted in Al (AA1050). The U-10Mo/AA1050 pairs were treated in two temperature (150 degree C and 550 degree C) with three soaking times (5h, 40h and 80h). From microstructure analyses, rapid diffusion of Al happened inside U-10Mo in the first heating at 540 degree C during 15 min, reaching 8 at%Al in a range of 200 {mu}m towards U-10Mo. Longer time (5, 40, 80h) at 550 degree C maintain this level of Al-content up to 1000 {mu}m inside U-10Mo. A minor depth ({approx}1 {mu}m) near the interdiffusion contact had higher Al-content, but not sufficient to form identifiable (U,Mo)Al{sub x} structures. Probably, residual elements reduced drastically the interdiffusion phenomena between U-10Mo and AA1050, maybe due to silicon presence. (author)

  8. On the impact of Vertical Alignment of MoS2 for Efficient Lithium Storage.

    Science.gov (United States)

    Shokhen, Victor; Miroshnikov, Yana; Gershinsky, Gregory; Gotlib, Noam; Stern, Chen; Naveh, Doron; Zitoun, David

    2017-06-12

    Herein, we report energy storage devices, which are based on densely packed, vertically aligned MoS2 (VA-MoS2) or planar oriented MoS2 (PO-MoS2) and compare their electrochemical performances. The VA-MoS2 films have been processed by chemical vapor deposition (CVD) to reach unprecedented micron-scale thick films while maintaining the vertical alignment for the whole thickness. The VA-MoS2 and the PO-MoS2 films form a high-performance Li-ion electrode, reaching the theoretical limits of reversible capacity for this material (800 mAh/g; twice the specific capacity of graphite). The vertical alignment allows faster charge-discharge rates while maintaining a high specific capacity (C-rate measurements). Noteworthy, the reversible cycling of the Li-ion electrode also benefits from the vertical alignment. In this article, we present the full synthesis, structural and electrochemical characterization of VA-MoS2 along with the properties of PO-MoS2 to deconvolute the intrinsic properties of MoS2 from the influence of the layers' orientation.

  9. Au@MoS2 Core-Shell Heterostructures with Strong Light-Matter Interactions.

    Science.gov (United States)

    Li, Yuan; Cain, Jeffrey D; Hanson, Eve D; Murthy, Akshay A; Hao, Shiqiang; Shi, Fengyuan; Li, Qianqian; Wolverton, Chris; Chen, Xinqi; Dravid, Vinayak P

    2016-12-14

    There are emerging opportunities to harness diverse and complex geometric architectures based on nominal two-dimensional atomically layered structures. Herein we report synthesis and properties of a new core-shell heterostructure, termed Au@MoS2, where the Au nanoparticle is snugly and contiguously encapsulated by few shells of MoS2 atomic layers. The heterostructures were synthesized by direct growth of multilayer fullerene-like MoS2 shell on Au nanoparticle cores. The Au@MoS2 heterostructures exhibit interesting light-matter interactions due to the structural curvature of MoS2 shell and the plasmonic effect from the underlying Au nanoparticle core. We observed significantly enhanced Raman scattering and photoluminescence emission on these heterostructures. We attribute these enhancements to the surface plasmon-induced electric field, which simulations show to mainly localize within the MoS2 shell. We also found potential evidence for the charge transfer-induced doping effect on the MoS2 shell. The DFT calculations further reveal that the structural curvature of MoS2 shell results in a modification of its electronic structure, which may facilitate the charge transfer from MoS2 to Au. Such Au@MoS2 core-shell heterostructures have the potential for future optoelectronic devices, optical imaging, and other energy-environmental applications.

  10. Direct Synthesis of Large-Area 2D Mo2C on In Situ Grown Graphene.

    Science.gov (United States)

    Geng, Dechao; Zhao, Xiaoxu; Chen, Zhongxin; Sun, Weiwei; Fu, Wei; Chen, Jianyi; Liu, Wei; Zhou, Wu; Loh, Kian Ping

    2017-09-01

    As a new member of the MXene group, 2D Mo 2 C has attracted considerable interest due to its potential application as electrodes for energy storage and catalysis. The large-area synthesis of Mo 2 C film is needed for such applications. Here, the one-step direct synthesis of 2D Mo 2 C-on-graphene film by molten copper-catalyzed chemical vapor deposition (CVD) is reported. High-quality and uniform Mo 2 C film in the centimeter range can be grown on graphene using a Mo-Cu alloy catalyst. Within the vertical heterostructure, graphene acts as a diffusion barrier to the phase-segregated Mo and allows nanometer-thin Mo 2 C to be grown. Graphene-templated growth of Mo 2 C produces well-faceted, large-sized single crystals with low defect density, as confirmed by scanning transmission electron microscopy (STEM) measurements. Due to its more efficient graphene-mediated charge-transfer kinetics, the as-grown Mo 2 C-on-graphene heterostructure shows a much lower onset voltage for hydrogen evolution reactions as compared to Mo 2 C-only electrodes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Sodium alginate-assisted exfoliation of MoS2 and its reinforcement in polymer nanocomposites.

    Science.gov (United States)

    Xuan, Dandan; Zhou, Yifeng; Nie, Wangyan; Chen, Pengpeng

    2017-01-02

    In this work, molybdenum disulfide (MoS2) nanosheets were facilely prepared by direct exfoliation of MoS2 in aqueous media with the assistance of sodium alginate (SA). Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectra results showed that the raw MoS2 was successfully exfoliated into few-layer MoS2 nanosheets (SA-MoS2). FTIR and thermal gravimetric analysis (TGA) investigations showed that the obtained MoS2 nanosheets were modified by SA after exfoliation and improved dispersion in water were achieved. The obtained SA-MoS2 nanosheets were employed to reinforce the water-soluble polymer SA. No obvious macroscopic phase separation could be found from the SA/SA-MoS2 films. Dynamic mechanical analysis (DMA) results showed that almost 9 times enhancement for the storage modulus of SA was achieved with the incorporation of only 0.5wt% of SA-MoS2, and the thermal stability of SA was also found improved with the addition of SA-MoS2 according to the thermal gravimetric analysis TGA results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Characterisation of electrodeposited and heat-treated Ni-Mo-P coatings

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Regis L.; Casciano, Paulo N.S.; Correia, Adriana N.; Lima-Neto, Pedro de, E-mail: pln@ufc.br [Departamento de Quimica Analitica e Fisico-Quimica, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

    2012-07-01

    The electrodeposition, hardness and corrosion resistance properties of Ni-Mo-P coatings were investigated. Characterisations of the electrodeposited coatings were carried out using scanning electron microscopy, X-ray diffraction and energy dispersive X-ray analysis techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarisation. Amorphous Ni-Mo-P coatings were successfully obtained by electrodeposition using direct current. The coating composition showed to be dependent on the bath composition, current density and bath temperature. Both P and Mo contents contribute for the hardness properties of the Ni-Mo-P coatings and the absence of cracks is a requirement to produce electrodeposited Ni-Mo-P coatings with good hardness properties. The hardness values increase with heat-treatment temperature due to the precipitation of Ni, Ni{sub 3}P and NiMo phases during the heat treatment. The corrosion resistance of the electrodeposited Ni-Mo-P amorphous coatings increases with P content in the layer. Among the electrodeposited Ni-Mo-P amorphous coatings, Ni{sub 78}Mo{sub 10}P{sub 12} presented the best hardness and corrosion-resistance properties. The results showed that the addition of P is beneficial for the hardness and corrosion resistance properties of the Ni-Mo-based coatings. (author)

  13. Electrical impact of MoSe2 on CIGS thin-film solar cells.

    Science.gov (United States)

    Hsiao, Kuo-Jui; Liu, Jing-Da; Hsieh, Hsing-Hua; Jiang, Ting-Shiuan

    2013-11-07

    The CIGS solar cell is one of the most promising photovoltaic devices due to the achievement of the highest conversion efficiency (>20%) among all thin-film solar cells. The CIGS cell has a glass/Mo/CIGS/CdS/TCO configuration, and the CIGS-Mo interface is a Schottky barrier to holes. During the sulfurization-after-selenization (SAS) CIGS formation process with H2Se gas, the Mo surface transforms naturally into MoSe2 at the CIGS-Mo interface. In this work, the electrical impact of MoSe2 on CIGS solar cells was investigated. Different CIGS-Mo interfaces were prepared with two CIGS processes. One is SAS, and the other is the sequential-sputtering-selenization CIGS process with Se gas. Formation of MoSe2 is hardly observed in the latter process. Samples were characterized by XRD, the van der Pauw method, reflectance, and visual inspection. Besides, Schottky barrier heights of cells were extracted from J-V-T measurements. For the first time, it was experimentally shown that the existence of thin MoSe2 film can decrease the apparent Schottky barrier height of CIGS solar cells. In addition, 1-dimensional numerical simulation showed that a larger barrier height affects both the fill factor and open-circuit voltage. Therefore, the formation of MoSe2 during the CIGS process should minimize the negative effect of Schottky barrier on solar-cell performances, especially with large Schottky barrier.

  14. Cognitive impairment in Chinese IIDDs revealed by MoCA and P300.

    Science.gov (United States)

    Zeng, Qiuming; Dong, Xiaohua; Ruan, Chunyun; Hu, Bo; Zhou, Binting; Xue, Yuanyuan; Liu, Yu; Yang, Huan

    2017-08-01

    To investigate the value of MoCA and auditory P300 as a cognitive assessment tool in chinese idiopathic inflammatory-demyelinating diseases (IIDDs), eighty three consecutive patients with IIDDs and thirteen sex- and age-matched healthy controls were recruited in the study. MMSE, MoCA and auditory P300 potential were administrated to each participant. The percentage of cognitive impairment in IIDDs patients was 24.1% by using MMSE, while the percentage was 81.9% by using MoCA. The majority of IIDDs participants had MMSE scores in the normal range. In contrast, few IIDDs participants scored in the normal range on the MoCA. Age, EDSS and depression correlated negatively with the total score of MoCA and MMSE. Years of education correlated positively with MoCA and MMSE. ADEM patients scored lower on all MoCA subtests. Prolonged latency P300 which negatively correlated with MoCA and reduced P300 amplitude which positively correlated with MoCA were detected in IIDDs patients. Thus MoCA is superior to the MMSE as a cognitive impairment scan tool and P300 is useful for detecting cogntive deficiency in chinese IIDDs. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. First-principles study of the surface properties of U-Mo system

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Zhi-Gang; Liang, Linyun; Yacout, Abdellatif M.

    2018-02-01

    U-Mo alloys are promising fuels for future high-performance research reactors with low enriched uranium. Surface properties, such as surface energy, are important inputs for mesoscale simulations (e.g., phase field method) of fission gas bubble behaviors in irradiated nuclear fuels. The lack of surface energies of U-Mo alloys prevents an accurate modeling of the morphology of gas bubbles and gas bubble-induced fuel swelling. To this end, we study the surface properties of U-Mo system, including bcc Mo, alpha-U, gamma-U, and gamma U-Mo alloys. All surfaces up to a maximum Miller index of three and two are calculated for cubic Mo and gamma-U and non-cubic alpha-U, respectively. The equilibrium crystal shapes of bcc Mo, alpha-U and gamma-U are constructed using the calculated surface energies. The dominant surface orientations and the area fraction of each facet are determined from the constructed equilibrium crystal shape. The disordered gamma U-Mo alloys are simulated using the Special Quasirandom Structure method. The (1 1 0) and (1 0 0) surface energies of gamma U-7Mo and U-10Mo alloys are predicted to lie between those of gamma-U and bcc Mo, following a linear combination of the two constituents' surface energies. To better compare with future measurements of surface energies, the area fraction weighted surface energies of alpha-U, gamma-U and gamma U-7Mo and U-10Mo alloys are also predicted. (C) 2017 Published by Elsevier B.V.

  16. MoS2/MX2 heterobilayers: bandgap engineering via tensile strain or external electrical field.

    Science.gov (United States)

    Lu, Ning; Guo, Hongyan; Li, Lei; Dai, Jun; Wang, Lu; Mei, Wai-Ning; Wu, Xiaojun; Zeng, Xiao Cheng

    2014-03-07

    We have performed a comprehensive first-principles study of the electronic and magnetic properties of two-dimensional (2D) transition-metal dichalcogenide (TMD) heterobilayers MX2/MoS2 (M = Mo, Cr, W, Fe, V; X = S, Se). For M = Mo, Cr, W; X = S, Se, all heterobilayers show semiconducting characteristics with an indirect bandgap with the exception of the WSe2/MoS2 heterobilayer which retains the direct-bandgap character of the constituent monolayer. For M = Fe, V; X = S, Se, the MX2/MoS2 heterobilayers exhibit metallic characters. Particular attention of this study has been focused on engineering the bandgap of the TMD heterobilayer materials via application of either a tensile strain or an external electric field. We find that with increasing either the biaxial or uniaxial tensile strain, the MX2/MoS2 (M = Mo, Cr, W; X = S, Se) heterobilayers can undergo a semiconductor-to-metal transition. For the WSe2/MoS2 heterobilayer, a direct-to-indirect bandgap transition may occur beyond a critical biaxial or uniaxial strain. For M (=Fe, V) and X (=S, Se), the magnetic moments of both metal and chalcogen atoms are enhanced when the MX2/MoS2 heterobilayers are under a biaxial tensile strain. Moreover, the bandgap of MX2/MoS2 (M = Mo, Cr, W; X = S, Se) heterobilayers can be reduced by the vertical electric field. For two heterobilayers MSe2/MoS2 (M = Mo, Cr), PBE calculations suggest that the indirect-to-direct bandgap transition may occur under an external electric field. The transition is attributed to the enhanced spontaneous polarization. The tunable bandgaps in general and possible indirect-direct bandgap transitions due to tensile strain or external electric field make the TMD heterobilayer materials a viable candidate for optoelectronic applications.

  17. Endothelin receptor B2 (EDNRB2 is responsible for the tyrosinase-independent recessive white (mo(w and mottled (mo plumage phenotypes in the chicken.

    Directory of Open Access Journals (Sweden)

    Keiji Kinoshita

    Full Text Available A mutation that confers white plumage with black eyes was identified in the Minohiki breed of Japanese native chicken (Gallus gallus domesticus. The white plumage, with a few partially pigmented feathers, was not associated with the tyrosinase gene, and displayed an autosomal recessive mode of inheritance against the pigmented phenotype. All F1 offspring derived from crosses with mottled chickens (mo/mo, which show characteristic pigmented feathers with white tips, had plumage with a mottled-like pattern. This result indicates that the white plumage mutation is a novel allele at the mo locus; we propose the gene symbol mo(w for this mutant allele. Furthermore, the F1 hybrid between the mo(w /mo(w chicken and the panda (s/s mutant of Japanese quail (Coturnix japonica, whose causative gene is the endothelin receptor B2 (EDNRB2 gene, showed a mo(w/mo(w chicken-like plumage, suggesting the possibility that the mutations in parental species are alleles of the same gene, EDNRB2. Nucleotide sequencing of the entire coding region of EDNRB2 revealed a non-synonymous G1008T substitution, which causes Cys244Phe amino acid substitution in exon 5 (which is part of the extracellular loop between the putative fourth and fifth transmembrane domains of EDNRB2 in the mutant chicken. This Cys244Phe mutation was also present in individuals of four Japanese breeds with white plumage. We also identified a non-synonymous substitution leading to Arg332His substitution that was responsible for the mottled (mo/mo plumage phenotype. These results suggest that the EDN3 (endothelin 3-EDNRB2 signaling is essential for normal pigmentation in birds, and that the mutations of EDNRB2 may cause defective binding of the protein with endothelins, which interferes with melanocyte differentiation, proliferation, and migration.

  18. Effect of Mo on the phase stability and elastic mechanical properties of Ti-Mo random alloys from ab initio calculations

    Science.gov (United States)

    Cao, Peiyu; Tian, Fuyang; Wang, Yandong

    2017-11-01

    Ti-Mo alloys are promising materials for shape memory alloys and biomedical materials. Whereas, the appearance of metastable ω phase can cause embrittlement and destroy the shape memory effect. In order to avoid the ω phase, the effect of Mo on the temperature dependent lattice parameters, phase stability and elastic mechanical properties of β, α, and ω Ti1-x Mo x (x  =  0-2.0) random alloys was systematically investigated by using the exact muffin-tin orbitals method in combination with the coherent potential approximation. The theoretical predictions for the lattice parameters are in good agreement with the available experiments. Results show that β Ti0.96Mo0.04 can almost transform to ω phase without lattice deformation and volume change, which suggests that the athermal ω phase is easier to precipitate and grow near 4 at.% Mo content in the β Ti1-x Mo x alloys. The critical content of Mo for the competed stabilization of β phase at T  =  300 K is ~11.2 at.%. Its valence electron concentration of 4.224 is viewed as a necessary criterion for the competed phase stability. The calculations of formation energy are used to explain successfully why the partitioning of Mo can be found in Ti0.91Mo0.09 alloy after annealing. Through the analysis of formation energy, both Mo addition and increasing temperature can stabilize the β phase. The calculated Cauchy pressure, Pugh’s ratio, Poisson ratio, and Young’s modulus suggests that ω phase is intrinsically brittle and has large Young’s modulus compared with β and α phases.

  19. Adsorption of DNA/RNA nucleobases onto single-layer MoS2 and Li-Doped MoS2: A dispersion-corrected DFT study

    Science.gov (United States)

    Sadeghi, Meisam; Jahanshahi, Mohsen; Ghorbanzadeh, Morteza; Najafpour, Ghasem

    2018-03-01

    The kind of sensing platform in nano biosensor plays an important role in nucleic acid sequence detection. It has been demonstrated that graphene does not have an intrinsic band gap; therefore, transition metal dichalcogenides (TMDs) are desirable materials for electronic base detection. In the present work, a comparative study of the adsorption of the DNA/RNA nucleobases [Adenine (A), Cytosine (C) Guanine (G), Thymine (T) and Uracil (U)] onto the single-layer molybdenum disulfide (MoS2) and Li-doped MoS2 (Li-MoS2) as a sensing surfaces was investigated by using Dispersion-corrected Density Functional Theory (D-DFT) calculations and different measure of equilibrium distances, charge transfers and binding energies for the various nucleobases were calculated. The results revealed that the interactions between the nucleobases and the MoS2 can be strongly enhanced by introducing metal atom, due to significant charge transfer from the Li atom to the MoS2 when Lithium is placed on top of the MoS2. Furthermore, the binding energies of the five nucleobases were in the range of -0.734 to -0.816 eV for MoS2 and -1.47 to -1.80 eV for the Li-MoS2. Also, nucleobases were adsorbed onto MoS2 sheets via the van der Waals (vdW) force. This high affinity and the renewable properties of the biosensing platform demonstrated that Li-MoS2 nanosheet is biocompatible and suitable for nucleic acid analysis.

  20. Ion-irradiation induced reduction in Sr2Fe1.5Mo0.5O6-δ perovskite

    Science.gov (United States)

    Wang, Siwei; Tang, Ming; Brinkman, Kyle S.; Chen, Fanglin (Frank)

    2014-05-01

    The incorporation of radioactive elements in fission products (FPs) into complex oxides, where the elements are constrained in the structure and enhanced leaching and radioactive stability can be obtained, is an active research area in the nuclear fuel cycle. Perovskite structured Sr2Fe1.5Mo0.5O6-δ (SFM) has the capability of incorporating several FPs (such as Sr and Mo) into the crystalline network simultaneously while maintaining a stabilized structure. The radiation damage effects on the structure changes of this polycrystalline SFM sample is conducted under various ion irradiations including 200 keV He ions to a fluence of 5 × 1020 ions m-2, 100 keV H to a fluence of 3 × 1021 ions cm-2, and 600 keV Kr ions to a fluence of 2.5 × 1019 ions m-2 at room temperature. Irradiation-induced structural evolution was examined by using grazing incidence X-ray diffraction and cross-sectional transmission electron microscopy. It was found that the irradiated SFM sample decomposed into a layered Sr4FeMoO8-δ based phase and a metallic Fe based phase under light ion (He and H) irradiations. Nano-crystallized secondary phase was observed with particle sizes around 7 nm. These results suggest that irradiation-induced reducing atmospheres may affect the stability of crystalline structure in complex oxides. Experiment results also reveal an amorphization in the heavy ion Kr irradiated sample, while no amorphization is observed in He/H irradiated SFM.

  1. Optimization of MoSe{sub 2} formation for Cu(In,Ga)Se{sub 2}-based solar cells by using thin superficial molybdenum oxide barrier layers

    Energy Technology Data Exchange (ETDEWEB)

    Duchatelet, A., E-mail: aurelien.duchatelet@edf.fr [Institute of Research and Development on Photovoltaic Energy (IRDEP), UMR 7174 EDF-CNRS-Chimie ParisTech, 6 quai Watier 78401, Chatou Cedex (France); Savidand, G. [Institute of Research and Development on Photovoltaic Energy (IRDEP), UMR 7174 EDF-CNRS-Chimie ParisTech, 6 quai Watier 78401, Chatou Cedex (France); Vannier, R.N. [Unité de Catalyse et Chimie du Solide (UCCS), UMR 8181, Ecole Nationale Supérieure de Chimie de Lille, Bat C7a-BP 90108, F-59652, Villeneuve d' Ascq (France); Lincot, D., E-mail: Daniel-Lincot@chimie-paristech.fr [Institute of Research and Development on Photovoltaic Energy (IRDEP), UMR 7174 EDF-CNRS-Chimie ParisTech, 6 quai Watier 78401, Chatou Cedex (France)

    2013-10-31

    During the formation of Cu(In,Ga)Se{sub 2} thin films deposited on Mo substrate by the selenization of Cu-In-Ga precursor, the reaction of Mo with Se can lead to a high consumption of Mo back contact and the formation of a thick MoSe{sub 2} layer, thus deteriorating the electrical properties of the back contact. In this study, the effect of thermal oxidation pre-treatment on Mo has been investigated to control the growth of MoSe{sub 2}. It has been demonstrated that a thin and covering MoO{sub 2} layer can block the selenization of Mo. Using this effect, a MoSe{sub 2} layer with controlled thickness can be formed by adding a thin and controlled Mo layer on top of an oxidized Mo substrate. In this configuration, only the Mo added on top of oxidized Mo forms MoSe{sub 2} and the whole Mo protected by MoO{sub 2} remains after selenization. Thanks to this Glass/Mo/MoO{sub 2}/Mo substrate configuration and the metallic behavior of MoO{sub 2}, the good electrical properties of the back contact are kept after selenization. - Highlights: • Selenization of Cu-In-Ga on Mo substrate produces thick detrimental MoSe{sub 2} layer. • MoO{sub 2} layer on Mo surface blocks MoSe{sub 2} formation. • Mo layer on top of MoO{sub 2}/Mo substrate enables to control MoSe{sub 2}.

  2. Enhancing the Understanding of Computer Networking Courses through Software Tools

    OpenAIRE

    Dafalla, Z. I.; Balaji, R. D.

    2015-01-01

    Computer networking is an important specialization in Information and Communication Technologies. However imparting the right knowledge to students can be a challenging task due to the fact that there is not enough time to deliver lengthy labs during normal lecture hours. Augmenting the use of physical machines with software tools help the students to learn beyond the limited lab sessions within the environment of higher Institutions of learning throughout the world. The Institutions focus mo...

  3. A Structural Study on the Foaming Behavior of CaO-SiO2-MO (MO = MgO, FeO, or Al2O3) Ternary Slag System

    Science.gov (United States)

    Park, Youngjoo; Min, Dong Joon

    2017-12-01

    The foaming index of the CaO-SiO2-MO (MO = MgO, FeO, or Al2O3) ternary slag system with a fixed CaO/SiO2 ratio is measured to understand the effect of the ionic structure. At 1773 K (1500 °C), the foaming index of the slag increases with Al2O3 addition and decreases with MgO or FeO addition at a fixed CaO/SiO2 ratio. It is verified that the previous correlation between the foaming index and the physical properties could also be valid for the CaO-SiO2-(MgO or Al2O3) system. Raman spectroscopy for the CaO/SiO2 = 1.0 slag is applied to explain the foaming behavior from an ionic structural perspective. From the ionic structural viewpoint, the fractional change in each silicate anion unit is identified by de-convoluted Raman spectra. The Raman spectra indicate that the silicate network structure is polymerized with Al2O3 as an aluminosilicate structure; in contrast, de-polymerization occurs by MgO or FeO addition. Furthermore, the relationship between the silicate structure and the thermodynamic stability function is discussed. Since the ionic structure of the molten slag affects various physical/thermodynamic properties, the foaming behavior could be successfully interpreted from the ionic structural viewpoint.

  4. The multi-objective network design problem using minimizing externalities as objectives: comparison of a genetic algorithm and simulated annealing framework.

    NARCIS (Netherlands)

    Possel, B.; Wismans, Luc Johannes Josephus; van Berkum, Eric C.; Bliemer, M.C.J.

    2016-01-01

    Incorporation of externalities in the Multi-Objective Network Design Problem (MO NDP) as objectives is an important step in designing sustainable networks. In this research the problem is defined as a bi-level optimization problem in which minimizing externalities are the objectives and link types

  5. Exfoliated MoS2 in Water without Additives.

    Directory of Open Access Journals (Sweden)

    Viviane Forsberg

    Full Text Available Many solution processing methods of exfoliation of layered materials have been studied during the last few years; most of them are based on organic solvents or rely on surfactants and other funtionalization agents. Pure water should be an ideal solvent, however, it is generally believed, based on solubility theories that stable dispersions of water could not be achieved and systematic studies are lacking. Here we describe the use of water as a solvent and the stabilization process involved therein. We introduce an exfoliation method of molybdenum disulfide (MoS2 in pure water at high concentration (i.e., 0.14 ± 0.01 g L-1. This was achieved by thinning the bulk MoS2 by mechanical exfoliation between sand papers and dispersing it by liquid exfoliation through probe sonication in water. We observed thin MoS2 nanosheets in water characterized by TEM, AFM and SEM images. The dimensions of the nanosheets were around 200 nm, the same range obtained in organic solvents. Electrophoretic mobility measurements indicated that electrical charges may be responsible for the stabilization of the dispersions. A probability decay equation was proposed to compare the stability of these dispersions with the ones reported in the literature. Water can be used as a solvent to disperse nanosheets and although the stability of the dispersions may not be as high as in organic solvents, the present method could be employed for a number of applications where the dispersions can be produced on site and organic solvents are not desirable.

  6. High-pressure behavior of CaMo O4

    Science.gov (United States)

    Panchal, V.; Garg, N.; Poswal, H. K.; Errandonea, D.; Rodríguez-Hernández, P.; Muñoz, A.; Cavalli, E.

    2017-09-01

    We report a high-pressure study of tetragonal scheelite-type CaMo O4 up to 29 GPa. In order to characterize its high-pressure behavior, we have combined Raman and optical-absorption measurements with density functional theory calculations. We have found evidence of a pressure-induced phase transition near 15 GPa. Experiments and calculations agree in assigning the high-pressure phase to a monoclinic fergusonite-type structure. The reported results are consistent with previous powder x-ray-diffraction experiments, but are in contradiction with the conclusions obtained from earlier Raman measurements, which support the existence of more than one phase transition in the pressure range covered by our studies. The observed scheelite-fergusonite transition induces significant changes in the electronic band gap and phonon spectrum of CaMo O4 . We have determined the pressure evolution of the band gap for the low- and high-pressure phases as well as the frequencies and pressure dependencies of the Raman-active and infrared-active modes. In addition, based on calculations of the phonon dispersion of the scheelite phase, carried out at a pressure higher than the transition pressure, we propose a possible mechanism for the reported phase transition. Furthermore, from the calculations we determined the pressure dependence of the unit-cell parameters and atomic positions of the different phases and their room-temperature equations of state. These results are compared with previous experiments showing a very good agreement. Finally, information on bond compressibility is reported and correlated with the macroscopic compressibility of CaMo O4 . The reported results are of interest for the many technological applications of this oxide.

  7. Greenfield Alternative Study LEU-Mo Fuel Fabrication Facility

    Energy Technology Data Exchange (ETDEWEB)

    Washington Division of URS

    2008-07-01

    This report provides the initial “first look” of the design of the Greenfield Alternative of the Fuel Fabrication Capability (FFC); a facility to be built at a Greenfield DOE National Laboratory site. The FFC is designed to fabricate LEU-Mo monolithic fuel for the 5 US High Performance Research Reactors (HPRRs). This report provides a pre-conceptual design of the site, facility, process and equipment systems of the FFC; along with a preliminary hazards evaluation, risk assessment as well as the ROM cost and schedule estimate.

  8. ¿Cómo seducir a un turista?

    Directory of Open Access Journals (Sweden)

    Luis Eladio Proaño

    2015-01-01

    Full Text Available Los profesionales del markenting destacan la importancia de conocer a fondo todo lo que concierne al cliente potencial. Para ellos es indispensable investigar sus valores culturales, sus posibilidades económicas y hábitos de consumo, y hasta sus fantasías íntimas. El objetivo de este artículo es explicar cómo se elabora un plan estratégico de mercadeo, para ello se vale de un plan presentado en Quito, (1991 para promover en los Estados Unidos.

  9. Conciencia agente: cómo sabemos lo que hacemos

    Directory of Open Access Journals (Sweden)

    Antoni Gomila

    2008-02-01

    Full Text Available ¿Cómo distinguimos qué movimientos son voluntarios y cuáles no? Gracias al trabajo de Sato y Yasuda (2005 sobre los factores determinantes de nuestra experiencia agente, parece que la clave está en que anticipamos de manera automática la estimulación sensorial propioceptiva que debe seguir a determinada intención motora, en una escala temporal muy precisa. Sus resultados avalan el modelo cibernético de control motor denominado "del modelo interno y la copia de eferencia".

  10. Study of Neutron-Unbound States with MoNA

    Science.gov (United States)

    Kuchera, A. N.; Spyrou, A.; Smith, J. K.; Baumann, T.; Christian, G.; De Young, P. A.; Finck, J. E.; Frank, N.; Jones, M. D.; Kohley, Z.; Mosby, S.; Peters, W. A.; Thoennessen, M.

    2015-06-01

    The Modular Neutron Array (MoNA) in conjunction with the large-gap Sweeper magnet at the NSCL is an effective setup to explore neutron-unbound states and has been operating for ten years. Neutron-unbound nuclei beyond the drip-line as well as neutron unbound excited states of bound nuclei have been populated primarily using proton removal reactions. A recent example, the search for 3n emission of the decay of 15Be to1 12Be, is discussed.

  11. Atomic and electronic structure of MoS2 nanoparticles

    DEFF Research Database (Denmark)

    Bollinger, Mikkel; Jacobsen, Karsten Wedel; Nørskov, Jens Kehlet

    2003-01-01

    at the edges. The electronic structure of the edge states is studied and we discuss their influence on the chemical properties of the edges. In particular, we study the reactivity towards hydrogen and show that hydrogen may form stable chemical bonds with both the two low-Miller indexed edges of MoS2. A model...... for calculating Gibbs free energy of the edges in terms of the DFT energies is also presented. This model allows us to determine the stable edge structure in thermodynamic equilibrium under different conditions. We find that both the insulating and metallic edges may be stable depending on the temperature...

  12. Carbides in Nodular Cast Iron with Cr and Mo

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2007-07-01

    Full Text Available In these paper results of elements microsegregation in carbidic nodular cast iron have been presented. A cooling rate in the centre of the cross-section and on the surface of casting and change of moulding sand temperature during casting crystallization and its self-cooling have been investigated. TDA curves have been registered. The linear distribution of elements concentration in an eutectic grain, primary and secondary carbides have been made. It was found, that there are two kinds of carbides: Cr and Mo enriched. A probable composition of primary and secondary carbides have been presented.

  13. SWCNT-MoS2 -SWCNT Vertical Point Heterostructures.

    Science.gov (United States)

    Zhang, Jin; Wei, Yang; Yao, Fengrui; Li, Dongqi; Ma, He; Lei, Peng; Fang, Hehai; Xiao, Xiaoyang; Lu, Zhixing; Yang, Juehan; Li, Jingbo; Jiao, Liying; Hu, Weida; Liu, Kaihui; Liu, Kai; Liu, Peng; Li, Qunqing; Lu, Wei; Fan, Shoushan; Jiang, Kaili

    2017-02-01

    A vertical point heterostructure (VPH) is constructed by sandwiching a two-dimensional (2D) MoS2 flake with two cross-stacked metallic single-walled carbon nanotubes. It can be used as a field-effect transistor with high on/off ratio and a light detector with high spatial resolution. Moreover, the hybrid 1D-2D-1D VPHs open up new possibilities for nanoelectronics and nano-optoelectronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Network interruptions

    CERN Document Server

    2005-01-01

    On Sunday 12 June 2005, a site-wide security software upgrade will be performed on all CERN network equipment. This maintenance operation will cause at least 2 short network interruptions of 2 minutes on each equipment item. There are hundreds of such items across the CERN site (Meyrin, Prévessin and all SPS and LHC pits), and it will thus take the whole day to treat them all. All network users and services will be affected. Central batch computing services will be interrupted during this period, expected to last from 8 a.m. until late evening. Job submission will still be possible but no jobs will actually be run. It is hoped to complete the computer centre upgrades in the morning so that stable access can be restored to lxplus, afs and nice services as soon as possible; this cannot be guaranteed, however. The opportunity will be used to interrupt and perform upgrades on the CERN Document Servers.

  15. Network Survivability

    DEFF Research Database (Denmark)

    Marzo, José L.; Stidsen, Thomas Riis; Ruepp, Sarah Renée

    2010-01-01

    – are vital to modern services such as mobile telephony, online banking and VoIP. This book examines communication networking from a mathematical viewpoint. The contributing authors took part in the European COST action 293 – a four-year program of multidisciplinary research on this subject. In this book...... they offer introductory overviews and state-of-the-art assessments of current and future research in the fields of broadband, optical, wireless and ad hoc networks. Particular topics of interest are design, optimization, robustness and energy consumption. The book will be of interest to graduate students......, researchers and practitioners in the areas of networking, theoretical computer science, operations research, distributed computing and mathematics....

  16. Nuclear networking.

    Science.gov (United States)

    Xie, Wei; Burke, Brian

    2017-07-04

    Nuclear lamins are intermediate filament proteins that represent important structural components of metazoan nuclear envelopes (NEs). By combining proteomics and superresolution microscopy, we recently reported that both A- and B-type nuclear lamins form spatially distinct filament networks at the nuclear periphery of mouse fibroblasts. In particular, A-type lamins exhibit differential association with nuclear pore complexes (NPCs). Our studies reveal that the nuclear lamina network in mammalian somatic cells is less ordered and more complex than that of amphibian oocytes, the only other system in which the lamina has been visualized at high resolution. In addition, the NPC component Tpr likely links NPCs to the A-type lamin network, an association that appears to be regulated by C-terminal modification of various A-type lamin isoforms. Many questions remain, however, concerning the structure and assembly of lamin filaments, as well as with their mode of association with other nuclear components such as peripheral chromatin.

  17. Photoemission Spectroscopy Characterization of Attempts to Deposit MoO2 Thin Film

    Directory of Open Access Journals (Sweden)

    Irfan

    2011-01-01

    Full Text Available Attempts to deposit molybdenum dioxide (MoO2 thin films have been described. Electronic structure of films, deposited by thermal evaporation of MoO2 powder, had been investigated with ultraviolet photoemission and X-ray photoemission spectroscopy (UPS and XPS. The thermally evaporated films were found to be similar to the thermally evaporated MoO3 films at the early deposition stage. XPS analysis of MoO2 powder reveals presence of +5 and +6 oxidation states in Mo 3d core level along with +4 state. The residue of MoO2 powder indicates substantial reduction in higher oxidation states while keeping +4 oxidation state almost intact. Interface formation between chloroaluminum phthalocyanine (AlPc-Cl and the thermally evaporated film was also investigated.

  18. Low-temperature atomic layer deposition of MoS{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Jurca, Titel; Wang, Binghao; Tan, Jeffrey M.; Lohr, Tracy L.; Marks, Tobin J. [Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, IL (United States); Moody, Michael J.; Henning, Alex; Emery, Jonathan D.; Lauhon, Lincoln J. [Department of Materials Science and Engineering, and the Materials Research Center, Northwestern University, Evanston, IL (United States)

    2017-04-24

    Wet chemical screening reveals the very high reactivity of Mo(NMe{sub 2}){sub 4} with H{sub 2}S for the low-temperature synthesis of MoS{sub 2}. This observation motivated an investigation of Mo(NMe{sub 2}){sub 4} as a volatile precursor for the atomic layer deposition (ALD) of MoS{sub 2} thin films. Herein we report that Mo(NMe{sub 2}){sub 4} enables MoS{sub 2} film growth at record low temperatures - as low as 60 C. The as-deposited films are amorphous but can be readily crystallized by annealing. Importantly, the low ALD growth temperature is compatible with photolithographic and lift-off patterning for the straightforward fabrication of diverse device structures. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Construction of MoS2/Si nanowire array heterojunction for ultrahigh-sensitivity gas sensor

    Science.gov (United States)

    Wu, Di; Lou, Zhenhua; Wang, Yuange; Xu, Tingting; Shi, Zhifeng; Xu, Junmin; Tian, Yongtao; Li, Xinjian

    2017-10-01

    Few-layer MoS2 thin films were synthesized by a two-step thermal decomposition process. In addition, MoS2/Si nanowire array (SiNWA) heterojunctions exhibiting excellent gas sensing properties were constructed and investigated. Further analysis reveals that such MoS2/SiNWA heterojunction devices are highly sensitive to nitric oxide (NO) gas under reverse voltages at room temperature (RT). The gas sensor demonstrated a minimum detection limit of 10 ppb, which represents the lowest value obtained for MoS2-based sensors, as well as an ultrahigh response of 3518% (50 ppm NO, ∼50% RH), with good repeatability and selectivity of the MoS2/SiNWA heterojunction. The sensing mechanisms were also discussed. The performance of the MoS2/SiNWA heterojunction gas sensors is superior to previous results, revealing that they have great potential in applications relating to highly sensitive gas sensors.

  20. Enhanced monolayer MoS2/InP heterostructure solar cells by graphene quantum dots

    Science.gov (United States)

    Wang, Peng; Lin, Shisheng; Ding, Guqiao; Li, Xiaoqiang; Wu, Zhiqian; Zhang, Shengjiao; Xu, Zhijuan; Xu, Sen; Lu, Yanghua; Xu, Wenli; Zheng, Zheyang

    2016-04-01

    We demonstrate significantly improved photovoltaic response of monolayer molybdenum disulfide (MoS2)/indium phosphide (InP) van der Waals heterostructure induced by graphene quantum dots (GQDs). Raman and photoluminescence measurements indicate that effective charge transfer takes place between GQDs and MoS2, which results in n-type doping of MoS2. The doping effect increases the barrier height at the MoS2/InP heterojunction, thus the averaged power conversion efficiency of MoS2/InP solar cells is improved from 2.1% to 4.1%. The light induced doping by GQD provides a feasible way for developing more efficient MoS2 based heterostructure solar cells.

  1. Phase Transition of MoS2 Bilayer Structures

    DEFF Research Database (Denmark)

    Pandey, Mohnish; Bothra, Pallavi; Pati, Swapan K.

    2016-01-01

    In the present study, using density functional calculations we have investigated a possible mechanism for the structural phase transition of the semiconducting bilayer 2H-MoS2 via lithiation. The results indicate that the addition of lithium to the bilayer 2H-MoS2 transforms the bilayer to a hete......In the present study, using density functional calculations we have investigated a possible mechanism for the structural phase transition of the semiconducting bilayer 2H-MoS2 via lithiation. The results indicate that the addition of lithium to the bilayer 2H-MoS2 transforms the bilayer...... microscopic mechanism of the phase transition in MoS2 and enriches the atomic scale understanding of the interaction of MoS2 with the alkali ions and other transition metal dichalcogenides manifesting a similar phase transition....

  2. Atomic scale onset of Al adhesion on Mo{sub 2}BC

    Energy Technology Data Exchange (ETDEWEB)

    Bolvardi, Hamid; Music, Denis, E-mail: music@mch.rwth-aachen.de; Schneider, Jochen M.

    2015-08-31

    We have explored interfacial interactions between a Mo–C terminated Mo{sub 2}BC(040) surface and an Al cluster using ab initio molecular dynamics. The Al cluster is disrupted and wets the Mo{sub 2}BC(040) surface. This can be understood based on the electronic structure. Across the Al–MoC interface C s–Al s hybridized states are formed. These bonds are stronger than the Al–Al intra-cluster bonds. Hence, the onset of Al adhesion is caused by bond formation across the Al–MoC interface. - Highlights: • Interfacial interactions between Mo{sub 2}BC and an Al cluster were explored. • Al forms bonds to C constituting the onset of Al adhesion on Mo{sub 2}BC. • These data are relevant for other carbide coatings.

  3. Interdiffusion behavior in sigma-phase using Ni3Al/Mo diffusion couples

    Directory of Open Access Journals (Sweden)

    Zhou C.

    2011-01-01

    Full Text Available The sigmaNiMo( Al phase was formed using Ni3Al/Mo diffusion couples at 1423, 1473 and 1523 K. The growth of formed phase and the concentration-distance profiles for each component in the diffusion couples were examined by electron probe microanalysis (EPMA. The activation energy for the parabolic growth of σ phase is found to be 525.3 kJ/mol. The concentration dependence and average ternary interdiffusion coefficients in single σ-NiMo(Al phase were calculated, and the Arrhenius equations of the D for the σ-NiMo(Al phase are calculated, the diffusional interaction between Ni, Mo and Al in σ-NiMo(Al phase was studied by the crossinterdiffusion coefficients. Moreover, these results were utilized to explain the σ phase formation and growth in γ’ phase.

  4. Mo-Isotopes in the Oceans and a Case Study From the Black Sea

    Science.gov (United States)

    Siebert, C.; Nagler, T. F.; Boettcher, M.; Kramers, J. D.

    2002-12-01

    Because of an increasing number of Mo isotope fractionation data, the geochemical cycle of Mo especially in the recent oceans is now better understood. Data presented here were determined using a Nu instruments MC-ICPMS and double spike techniques (external reproducibility generally below 0.1 permil (2s.d.) on 98Mo/95Mo). Mo isotopes are homogenous in the oceans (+2.3 delta 98Mo/95Mo relative to JMC in-house standard) at present day resolution. All data are therefore given in delta notation relative to Mean Ocean water Mo (MOMO). Mo-Sources: Continental rocks, assumed to represent the riverrhine input, show a narrow range of Mo isotope compositions (-2.0 to -2.3 permil) close to the in-house standard solution. Oxic Mo-sinks: Pelagic sediments and recent Fe-Mn crust surfaces show lighter Mo isotope compositions (-2.7 to -3.2 permil). In addition, to depth profiles through thick sections of Fe-Mn crusts also yield uniform Mo isotope compositions (average of -2.9 and -3.2) over the last 60Ma implying a homogenous isotope composition in ocean water over this time period. This makes Mo different from other oceanic proxies since the large variations in environmental parameters seem to have not affected Mo. We explain the observed general offset of about 3 permil from ocean water with an equilibrium fractionation between major and minor Mo species in the water column, of which the latter are lighter and can be scavenged more efficiantly due to higher coordination numbers. Suboxic Mo-sinks: The balancing heavier Mo isotope composition with respect to the input can be found in recent suboxic sediments from open ocean basins, which display variable values but are all heavier than the input (-0.7 to -1.6 permil). The influence of Low-T hydrothermal activity on the Mo isotope budget in the oceans is still to be tested. Mo isotopes in the Black-Sea: Because of its limited water exchange with the open oceans, the high surface freshwater content (1/3) and its widespread bottom

  5. Wear tests in a hip joint simulator of different CoCrMo counterfaces on UHMWPE

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Mora, V.A.; Hoffmann, M.; Stroosnijder, R. [Institute for Health and Consumer Protection, Joint Research Centre, European Commission, Ispra (Italy); Gil, F.J. [CREB, Dept. Ciencia de Materiales e Ingenieria Metalurgica, ETSEIB, Universidad Politecnica de Cataluna, Av. Diagonal 647, 08028-Barcelona (Spain)], E-mail: francesc.xavier.gil@upc.edu

    2009-01-01

    The objective in this work was to study the effect of different material counterfaces on the Ultra High Molecular Weight Polyethylene (UHMWPE) wear behavior. The materials used as counterfaces were based on CoCrMo: forged with hand polished and mass finished, CoCrMo coating applied on the forged CoCrMo alloy obtained by Physical Vapour Deposition (PVD). A hip joint simulator was designed and built for these studies. The worn surfaces were observed by optical and scanning electron microscopy. The results showed that the hand polished CoCrMo alloy caused the higher UHMWPE wear of the acetabular cups. The CoCrMo coating caused the least UHMWPE wear, while the mass finished CoCrMo alloy caused an intermediate UHMWPE wear. It is shown that the wear rates obtained in this work are closer to clinical studies than to similar hip joints simulator studies.

  6. Corrosion Resistance of Powder Metallurgy Processed TiC/316L Composites with Mo Additions

    Science.gov (United States)

    Lin, Shaojiang; Xiong, Weihao

    2015-06-01

    To find out the effects of Mo addition on corrosion resistance of TiC/316L stainless steel composites, TiC/316L composites with addition of different contents of Mo were prepared by powder metallurgy. The corrosion resistance of these composites was evaluated by the immersion tests and polarization curves experiments. Results indicated that Mo addition decreased the corrosion rates of TiC/316L composites in H2SO4 solution in the case of Mo content below 2% whereas it displayed an opposite effect when Mo content was above that value. It was found that with an increase in the Mo content, the pitting corrosion resistance increased monotonically for TiC/316L composites in NaCl solution.

  7. Supporting data for senary refractory high-entropy alloy CrxMoNbTaVW

    Directory of Open Access Journals (Sweden)

    B. Zhang

    2015-12-01

    Full Text Available This data article is related to the research paper entitled “senary refractory high-entropy alloy CrxMoNbTaVW [1]”. In this data article, the pseudo-binary Cr-MoNbTaVW phase diagram is presented to show the impact of Cr content to the senary Cr-MoNbTaVW alloy system; the sub-lattice site fractions are presented to show the disordered property of the Cr-MoNbTaVW BCC structures; the equilibrium and Scheil solidification results with the actual sample elemental compositions are presented to show the thermodynamic information of the melted/solidified CrxMoNbTaVW samples; and the raw EDS scan data of the arc-melted CrxMoNbTaVW samples are also provided.

  8. Industrial Networks

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    the focus of operations management from managing the own organization to continuously developing and managing a network of external and internal resources forming a production system. This perspective may be called managing an “extraprise” rather than an “enterprise.” It should be noted that “an industrial...... network” should not be seen as an organizational form but as a perspective that can be used to enrich one's understanding of organizations. The industrial network perspective has three basic building blocks: actors, resources, and activities. The three building blocks and their relations constitute...

  9. Structure and properties of the Mo3Nb2O14 oxide.

    Science.gov (United States)

    Afanasiev, Pavel

    2005-10-06

    Mixed Nb-Mo oxides were prepared by solid-state reaction of Nb(V) and Mo(VI) oxides at 973-1123 K. Optimal conditions were determined for the formation of the Mo3Nb2O14 compound. As established by Rietveld refinement of the powder X-ray diffraction patterns, the Mo3Nb2O14 oxide has the tetragonal cell with a = 23.150(6) A and c = 3.998(4) A and a tunnel structure similar to that of the Mo5O14 oxide. The solids were characterized by several physical techniques, including scanning and transmission electron microscopy, FT-IR, UV-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and electron spin resonance spectroscopy. It has been shown that the Mo3Nb2O14 solid prepared in air at 973-1073 K after cooling to room temperature contains high amounts of Mo(V) species (ca. 1% of total molybdenum). The presence of paramagnetic species correlates with the intense green color of the solids and the strong d-d transition band in the UV-visible spectra, typical for the d1 species. The amount of paramagnetic species does not depend on the solid annealing and/or on the small variations of its composition. Neither is it related to the oxygen release upon the solid heating, being therefore an intrinsic property of the Mo3Nb2O14 oxide. The unusual stabilization of reduced Mo species in the highly oxidizing conditions was explained by the substitution disorder between Nb and Mo atoms. It is supposed that a configuration containing mu3 oxygen bonded to three Mo(VI) atoms is unstable and decomposes, leading to a Mo(V) center and a hole in the valence band.

  10. The electron transfer series [Mo(III)(bpy)3](n) (n = 3+, 2+, 1+, 0, 1-), and the dinuclear species [{Mo(III)Cl((Me)bpy)2}2(μ2-O)]Cl2 and [{Mo(IV)(tpy·)2}2(μ2-MoO4)](PF6)2⋅4 MeCN.

    Science.gov (United States)

    Wang, Mei; Weyhermüller, Thomas; Wieghardt, Karl

    2014-07-14

    The electronic structures of the five members of the electron transfer series [Mo(bpy)3](n) (n = 3+, 2+, 1+, 0, 1-) are determined through a combination of techniques: electro- and magnetochemistry, UV/Vis and EPR spectroscopies, and X-ray crystallography. The mono- and dication are prepared and isolated as PF6 salts for the first time. It is shown that all species contain a central Mo(III) ion (4d(3)). The successive one-electron reductions/oxidations within the series are all ligand-based, involving neutral (bpy(0)), the π-radical anion (bpy·)(1-), and the diamagnetic dianion (bpy(2-))(2-): [Mo(III)(bpy(0))3](3+) (S = 3/2), [Mo(III)(bpy·)(bpy(0))2](2+) (S = 1), [Mo(III)(bpy·)2(bpy(0))](1+) (S = 1/2), [Mo(III)(bpy·)3] (S = 0), and [Mo(III)(bpy·)2(bpy(2-))](1-) (S = 1/2). The previously described diamagnetic dication "[Mo(II)(bpy(0))3](BF4)2" is proposed to be a diamagnetic dinuclear species [{Mo(bpy)3}2(μ2-O)](BF4)4. Two new polynuclear complexes are prepared and structurally characterized: [{Mo(III)Cl((Me)bpy(0))2}2(μ2-O)]Cl2 and [{Mo(IV)(tpy·)2}2(μ2-Mo(VI)O4)](PF6)2⋅4 MeCN. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Understanding Aqueous Stability and Filtration Capability of MoS2 Membranes.

    Science.gov (United States)

    Wang, Zhongying; Tu, Qingsong; Zheng, Sunxiang; Urban, Jeffrey J; Li, Shaofan; Mi, Baoxia

    2017-11-21

    Membranes made of layer-stacked two-dimensional molybdenum disulfide (MoS2) nanosheets have recently shown great promise for water filtration. At present, the reported water fluxes vary significantly while the accountable structure and properties of MoS2 nanochannels are largely unknown. This paper aims to mechanistically relate the performance of MoS2 membranes to the size of their nanochannels in different hydration states. We discovered that fully hydrated MoS2 membranes retained a 1.2-nm interlayer spacing (or 0.9-nm free spacing), leading to high water permeability and moderate-to-high ionic/molecular rejection. In comparison, completely dry MoS2 membranes had a 0.62-nm interlayer spacing (or 0.3-nm free spacing) due to irreversible nanosheet restacking and were almost impermeable to water. Furthermore, we revealed that the interlayer spacing of MoS2 membranes in aqueous solution is maintained by comparable van der Waals and hydration forces, thereby ensuring the aqueous stability of MoS2 membranes without the need of crosslinking. In addition, we attributed the high water flux (30-250 L m-2 h-1 bar-1) of MoS2 membranes to the low hydraulic resistance of smooth, rigid MoS2 nanochannels. We also concluded that compaction of MoS2 membranes with a high pressure helps create a more neatly stacked nanostructure with minimum voids or looseness, leading to stable water flux and separation performance. Besides, this paper systematically compares MoS2 membranes with the widely studied graphene oxide membranes to highlight the uniqueness and advantages of MoS2 membranes for water filtration applications.

  12. Study on the performance of MoS2 modified PTFE composites by molding process

    Science.gov (United States)

    Ma, Weiqiang; Hou, Genliang; Bi, Song; Li, Ping; Li, Penghui

    2017-10-01

    MoS2 filled PTFE composites were prepared by cold pressing and sintering molding. The compressive and creep properties of composite materials were analyzed by controlling the size of molded composites during molding. The results show that the composites have the best compressive and creep resistance when the molding pressure is 55 MPa in the MoS2 composites with 15% mass fraction, which is a practical reference for the preparation of MoS2-modified PTFE composites.

  13. Atomic Layer Etching Mechanism of MoS2 for Nanodevices.

    Science.gov (United States)

    Kim, Ki Seok; Kim, Ki Hyun; Nam, Yeonsig; Jeon, Jaeho; Yim, Soonmin; Singh, Eric; Lee, Jin Yong; Lee, Sung Joo; Jung, Yeon Sik; Yeom, Geun Young; Kim, Dong Woo

    2017-04-05

    Among the layered transition metal dichalcogenides (TMDs) that can form stable two-dimensional crystal structures, molybdenum disulfide (MoS2) has been intensively investigated because of its unique properties in various electronic and optoelectronic applications with different band gap energies from 1.29 to 1.9 eV as the number of layers decreases. To control the MoS2 layers, atomic layer etching (ALE) (which is a cyclic etching consisting of a radical-adsorption step such as Cl adsorption and a reacted-compound-desorption step via a low-energy Ar(+)-ion exposure) can be a highly effective technique to avoid inducing damage and contamination that occur during the reactive steps. Whereas graphene is composed of one-atom-thick layers, MoS2 is composed of three-atom-thick S(top)-Mo(mid)-S(bottom) layers; therefore, the ALE mechanisms of the two structures are significantly different. In this study, for MoS2 ALE, the Cl radical is used as the adsorption species and a low-energy Ar(+) ion is used as the desorption species. A MoS2 ALE mechanism (by which the S(top), Mo(mid), and S(bottom) atoms are sequentially removed from the MoS2 crystal structure due to the trapped Cl atoms between the S(top) layer and the Mo(mid) layer) is reported according to the results of an experiment and a simulation. In addition, the ALE technique shows that a monolayer MoS2 field effect transistor (FET) fabricated after one cycle of ALE is undamaged and exhibits electrical characteristics similar to those of a pristine monolayer MoS2 FET. This technique is also applicable to all layered TMD materials, such as tungsten disulfide (WS2), molybdenum diselenide (MoSe2), and tungsten diselenide (WSe2).

  14. A {sup 99m}Tc Generator using PZC for (n,{gamma}) {sup 99}Mo

    Energy Technology Data Exchange (ETDEWEB)

    Adang, H.G.; Mutalib, A.; Suparman, I.; Hamid; Purwadi, B.; Pancoko, M.; Setiowati, S.; Yulianti, V.; Robertus, D.H. [Radioisotope Production Center, National Atomic Energy Agency Kawasan PUSPIPTEK, Serpong (Indonesia)

    1998-10-01

    The high performance adsorbent Poly Zirconium Compound (PZC) was produced by Department of Radioisotope, Japan Atomic Energy Research Institute. This compound was developed as an adsorbent for natural Mo (n,{gamma}) {sup 99}Mo-{sup 99m}Tc Generator. In the present paper, we report the performance of the PZC for a {sup 99m}Tc Generator which was focused on the yield, on elution profile and {sup 99}Mo breakthrough. (author)

  15. Two-Dimensional MoS2 Transistors for Low- Power RF Applications

    Science.gov (United States)

    2015-03-16

    performance, we completed several growth runs with iterative optimization, conducted material characterization ( Raman scans, photoluminescence, hall mobility...and multilayers is grown by sulfurization of thin layers of ebeam- deposited Mo film. Figure 2 (right) shows the growth obtained on quartz substrates...Fresh Mo and sulfurized MoS2 films on quartz substrate showing various thicknesses. Figure 2. Optical micrographs showing the samples before and

  16. Effect of Mo ion-implantation on the adhesion of diamond coatings

    CERN Document Server

    Yang Shie; Wang Xiao Ping; Li Hui; Ma Bing Xian; Qin Guang Yong; Zhang Bing Lin

    2002-01-01

    Diamond coatings were deposited on the cobalt-cemented tungsten carbide (YG6) substrates, which have been implanted with Mo ions, by microwave plasma CVD (MPCVD) method. The effect of ion-implantation on the adhesion of diamond coatings was studied. The results showed that the chemical compositions of cemented carbide substrate surfaces change obviously after Mo ion-implantation; and the adhesion strength between the CVD diamond coatings and the substrates implanted with Mo ions in proper concentration is improved remarkably

  17. Ammoxidation of 2-methyl pyrazine to 2-cyano pyrazine on MoO 3 ...

    Indian Academy of Sciences (India)

    The objective of this work is to understand the influence of small amount of Mo=O (1, 3 and 5wt.% MoO3) impregnated on FePO4 and its resultant effect on the acidity was studied for the ammoxidation of 2-methyl pyrazine (2-MP) to 2-cyano pyrazine (2-CP) in the temperature range of 380–420°C. The Mo/FeP catalyst ...

  18. The physics programme of the MoEDAL experiment at the LHC

    OpenAIRE

    Acharya B; Alexandre J; Bernabeu J.; Campbell M.; Cecchini S.; Chwastowski J.; De Montigny M.; Derendarz D.; De Roeck A.; Ellis J. R.; Fairbairn M.; Felea D.; Frank M.; Frekers D.; Garcia C.

    2014-01-01

    The MoEDAL experiment at Point 8 of the LHC ring is the seventh and newest LHC experiment. It is dedicated to the search for highly ionizing particle avatars of physics beyond the Standard Model extending significantly the discovery horizon of the LHC. A MoEDAL discovery would have revolutionary implications for our fundamental understanding of the Microcosm. MoEDAL is an unconventional and largely passive LHC detector comprised of the largest array of Nuclear Track Detector stacks ever deplo...

  19. Atomically Thin-Layered Molybdenum Disulfide (MoS2) for Bulk-Heterojunction Solar Cells.

    Science.gov (United States)

    Singh, Eric; Kim, Ki Seok; Yeom, Geun Young; Nalwa, Hari Singh

    2017-02-01

    Transition metal dichalcogenides (TMDs) are becoming significant because of their interesting semiconducting and photonic properties. In particular, TMDs such as molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), tungsten disulfide (WS2), tungsten diselenide (WSe2), titanium disulfide (TiS2), tantalum sulfide (TaS2), and niobium selenide (NbSe2) are increasingly attracting attention for their applications in solar cell devices. In this review, we give a brief introduction to TMDs with a focus on MoS2; and thereafter, emphasize the role of atomically thin MoS2 layers in fabricating solar cell devices, including bulk-heterojunction, organic, and perovskites-based solar cells. Layered MoS2 has been used as the hole-transport layer (HTL), electron-transport layer (ETL), interfacial layer, and protective layer in fabricating heterojunction solar cells. The trilayer graphene/MoS2/n-Si solar cell devices exhibit a power-conversion efficiency of 11.1%. The effects of plasma and chemical doping on the photovoltaic performance of MoS2 solar cells have been analyzed. After doping and electrical gating, a power-conversion efficiency (PCE) of 9.03% has been observed for the MoS2/h-BN/GaAs heterostructure solar cells. The MoS2-containing perovskites-based solar cells show a PCE as high as 13.3%. The PCE of MoS2-based organic solar cells exceeds 8.40%. The stability of MoS2 solar cells measured under ambient conditions and light illumination has been discussed. The MoS2-based materials show a great potential for solar cell devices along with high PCE; however, in this connection, their long-term environmental stability is also of equal importance for commercial applications.

  20. Synthesising Fe-Mo catalysts supported on silica for the selective oxidation of methane to formaldehyde

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Guerrero Fajardo

    2010-05-01

    Full Text Available The selective oxidation of methane to formaldehyde was analysed using iron-molybdenum catalysts supported on silica prepared by the sol-gel method which leads to obtaining a greater surface area and high iron and molybdenum metal dispersion on the si-lica’s amorphous surface. Seven catalysts were prepared, one of them as silica support, another as 0.5% wt iron load without molybdenum and the remaining five having 0.1%-1.0% weight molybdenum and 0.5% wt iron loads. The highest BET areas were 830 and 879 m2.g-1 for catalysts 2 (0.5% Fe - 0% Mo and 4 (0.5% Fe - 0.3% Mo respectively, having 28% average micropo-rosity and 47% average mesoporosity. X-ray diffraction confirmed the catalysts’ amorphous structure. The TPR spectrum showed low hydrogen consumption attributed to the absence of isolated Fe and Mo species. ESCA analysis revealed the same Fe/Mo a-tomic ratio on the catalyst surface as in the bulk preparation. Catalytic activity was carried out at atmospheric pressure, CH4/ O2/N2 = 7.5/1/4 reaction mixture, 400-800°C temperature interval. Catalysts 4 (0.5% Fe - 0.3% Mo, 5 (0.5% Fe - 0.5% Mo and 7 (0.5% Fe - 1.0% Mo displayed greater methane conversion, whereas catalysts 5 (0.5% Fe - 0.5% Mo, 4 (0.5% Fe - 0.3% Mo, 2 (0.5% Fe - 0% Mo and 7 (0.5% Fe - 1.0% Mo gave better formaldehyde product results. The highest conversion per- centage (4.07% mol was presented at 700°C for catalyst 4 (0.5% Fe-0.3% Mo. Formaldehyde yield was 202,0 gHCHO.kg-1 cata.h-1 at this temperature.