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Sample records for networks mo sha

  1. 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...

  2. The first collision for full SHA-1

    NARCIS (Netherlands)

    M.M.J. Stevens (Marc); E. Bursztein (Elie); P. Karpman (Pierre); A. Albertini (Ange); Y. Markov (Yarik)

    2017-01-01

    textabstractSHA-1 is a widely used 1995 NIST cryptographic hash function standard that was officially deprecated by NIST in 2011 due to fundamental security weaknesses demonstrated in various analyses and theoretical attacks. Despite its deprecation, SHA-1 remains widely used in 2017 for document

  3. 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

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

    CSIR Research Space (South Africa)

    Motara, YM

    2017-09-01

    Full Text Available the intersection between the SHA-1 preimage problem, the encoding of that problem for SAT-solving, and SAT-solving. The results demonstrate that SAT-solving is not yet a viable approach to take to solve the preimage problem, and also indicate that some...

  5. 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

  6. 76 FR 11433 - Federal Transition To Secure Hash Algorithm (SHA)-256

    Science.gov (United States)

    2011-03-02

    ... ADMINISTRATION [FAR-N-2011-01; Docket No. 2011-0083; Sequence 1] Federal Transition To Secure Hash Algorithm (SHA... acquisition community to transition to Secure Hash Algorithm SHA-256. SHA-256 is a cryptographic hash function... persons attending. Please cite ``Federal Transition to Secure Hash Algorithm SHA-256'' in all...

  7. 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.

  8. 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...

  9. 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 in t...

  10. 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].

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

    DEFF Research Database (Denmark)

    Andreeva, Elena; Bogdanov, Andrey; Mennink, Bart

    2012-01-01

    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...... and review arguments and bounds against classes of differential attacks.We discuss all the SHA-3 candidates at a high functional level, analyze, and summarize the security reduction results and bounds against differential attacks. Additionally, we generalize the well-known proof of collision resistance...

  12. 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

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

    International Nuclear Information System (INIS)

    Susmikanti, Mike; Sulistyo, Jos

    2014-01-01

    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

  14. [Diagnosis and treatment characteristics of head-wind sha in She medicine].

    Science.gov (United States)

    Zou, Guangyi; Xu, Xiangdong; Zheng, Songming; Yan, Lianhe; Lei, Houxing; Zhang, Qiao-ling; Xiang, Yingmei; Ye, Yiping; Song, Liwei

    2015-03-01

    The diagnosis and treatment characteristics of head-wind sha in She medicine were analyzed and summarized. By visiting She-nationality villages and towns in Zhejiang province and Fujian province and interviewing hundreds of doctors of She medicine, the sha diagnosis, sha differentiation, experience and theory of treatment were arranged, and a comprehensive summary on theory and application of head-wind sha in She medicine such as pathogeny, name of disease, mechanism, diagnosis, differential diagnosis and treatment was made. It is believed that the methods of diagnosis and treatment in She medicine for head-wind sha could effectively enhance curative effect, safety and patients' quality of life, and the further research should be carried out.

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

    Energy Technology Data Exchange (ETDEWEB)

    Johns, Jesse M., E-mail: jesse.johns@pnnl.gov; Burkes, Douglas, E-mail: douglas.burkes@pnnl.gov

    2017-07-15

    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.

  16. 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.

  17. A one-time pad color image cryptosystem based on SHA-3 and multiple chaotic systems

    Science.gov (United States)

    Wang, Xingyuan; Wang, Siwei; Zhang, Yingqian; Luo, Chao

    2018-04-01

    A novel image encryption algorithm is proposed that combines the SHA-3 hash function and two chaotic systems: the hyper-chaotic Lorenz and Chen systems. First, 384 bit keystream hash values are obtained by applying SHA-3 to plaintext. The sensitivity of the SHA-3 algorithm and chaotic systems ensures the effect of a one-time pad. Second, the color image is expanded into three-dimensional space. During permutation, it undergoes plane-plane displacements in the x, y and z dimensions. During diffusion, we use the adjacent pixel dataset and corresponding chaotic value to encrypt each pixel. Finally, the structure of alternating between permutation and diffusion is applied to enhance the level of security. Furthermore, we design techniques to improve the algorithm's encryption speed. Our experimental simulations show that the proposed cryptosystem achieves excellent encryption performance and can resist brute-force, statistical, and chosen-plaintext attacks.

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

    NARCIS (Netherlands)

    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

    2013-01-01

    ABSTRACTS BACKGROUND: 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

  19. 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...

  20. Effects of Gua-Sha therapy on breast engorgement: a randomized controlled trial.

    Science.gov (United States)

    Chiu, Jin-Yu; Gau, Meei-Ling; Kuo, Shu-Yu; Chang, Yung-Hsien; Kuo, Su-Chen; Tu, Hui-Chuan

    2010-03-01

    Breast engorgement is a common problem that affects the initiation and duration of breastfeeding. Limited solutions are available to relieve the discomfort associated with breast engorgement. Thus, further investigation of methods to achieve effective relief of symptoms is critical to promote breastfeeding success. : The purpose of this study was to determine the effects of two breast care methods, that is, scraping (Gua-Sha) therapy (administered to the experimental group) and traditional breast care (i.e., massage and heating; administered to the control group). A randomized controlled trial was conducted on 54 postpartum women at a Level III medical teaching hospital. Participant inclusion criteria included postpartum breastfeeding women (a) who had an uncomplicated delivery and (b) who were experiencing breast engorgement problems. The Gua-Sha protocol selected appropriate acupoint positions, which included ST16, ST18, SP17, and CV17. Each position was lightly scraped seven times in two cycles. For the control group, we used hot packs and massage for 20 min in accordance with recommendations given in an obstetrical technique textbook. Results showed no statistical differences between the two groups at baseline. Body temperature, breast temperature, breast engorgement, pain levels, and discomforting levels were statistically different between the two groups at 5 and 30 min after intervention (p account. Our findings provided empirical evidence supporting that Gua-Sha therapy may be used as an effective technique in the management of breast engorgement. By using Gua-Sha therapy, nurses can handle breast engorgement problems more effectively in primary care and hence help patients both physically and psychologically.

  1. A comparative study of Message Digest 5(MD5) and SHA256 algorithm

    Science.gov (United States)

    Rachmawati, D.; Tarigan, J. T.; Ginting, A. B. C.

    2018-03-01

    The document is a collection of written or printed data containing information. The more rapid advancement of technology, the integrity of a document should be kept. Because of the nature of an open document means the document contents can be read and modified by many parties so that the integrity of the information as a content of the document is not preserved. To maintain the integrity of the data, it needs to create a mechanism which is called a digital signature. A digital signature is a specific code which is generated from the function of producing a digital signature. One of the algorithms that used to create the digital signature is a hash function. There are many hash functions. Two of them are message digest 5 (MD5) and SHA256. Those both algorithms certainly have its advantages and disadvantages of each. The purpose of this research is to determine the algorithm which is better. The parameters which used to compare that two algorithms are the running time and complexity. The research results obtained from the complexity of the Algorithms MD5 and SHA256 is the same, i.e., ⊖ (N), but regarding the speed is obtained that MD5 is better compared to SHA256.

  2. 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, J.; Schutz, J.; Chirayath, V.; Li, A.

    2017-12-01

    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-Net's 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 utilizes 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.

  3. 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.

  4. 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

  5. How to apply SHA 2011 at a subnational level in China's practical situation: take children health expenditure as an example.

    Science.gov (United States)

    Li, Mingyang; Zheng, Ang; Duan, Wenjuan; Mu, Xin; Liu, Chunli; Yang, Yang; Wang, Xin

    2018-06-01

    System of Health Accounts 2011 (SHA 2011) is a new health care accounts system, revised from SHA 1.0 by the Organisation for Economic Co-operation and Development (OECD), the World Health Organization (WHO) and Eurostat. It keeps the former tri-axial relationship and develops three analytical interfaces, in order to fix the existing shortcomings and make it more convenient for analysis and comparison across countries. SHA 2011 was introduced in China in 2014, and little about its application in China has been reported. This study takes children as an example to study how to apply SHA 2011 at the subnational level in the practical situation of China's health system. Multistage random sampling method was applied and 3 532 517 samples from 252 institutions were included in the study. Official yearbooks and account reports helped the estimation of provincial data. The formula to calculate Current Health Expenditure (CHE) was introduced step-by-step. STATA 10.0 was used for statistics. Under the frame of SHA 2011, the CHE for children in Liaoning was calculated as US$ 0.74 billion in 2014; 98.56% of the expenditure was spent in hospital and the allocation to primary health care institutions was insufficient. Infection, maternal and prenatal diseases cost the most in terms of Global Burden of Disease (GBD), and respiratory system diseases took the leading place in terms of International Classification of Disease Tenth Revision (ICD-10). In addition, medical income contributed most to the health financing. The method to apply SHA 2011 at the subnational level is feasible in China. It makes health accounts more adaptable to rapidly developing health systems and makes the financing data more readily available for analytical use. SHA 2011 is a better health expenditure accounts system to reveal the actual burden on residents and deserves further promotion in China as well as around the world.

  6. NeMO-Net - The Neural Multi-Modal Observation & Training Network for Global Coral Reef Assessment

    Science.gov (United States)

    Li, A. S. X.; Chirayath, V.; Segal-Rosenhaimer, M.; Das, K.

    2017-12-01

    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% 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 Python's extensive libraries for machine learning, as well as extending integration to GPU

  7. BioShaDock: a community driven bioinformatics shared Docker-based tools registry.

    Science.gov (United States)

    Moreews, François; Sallou, Olivier; Ménager, Hervé; Le Bras, Yvan; Monjeaud, Cyril; Blanchet, Christophe; Collin, Olivier

    2015-01-01

    Linux container technologies, as represented by Docker, provide an alternative to complex and time-consuming installation processes needed for scientific software. The ease of deployment and the process isolation they enable, as well as the reproducibility they permit across environments and versions, are among the qualities that make them interesting candidates for the construction of bioinformatic infrastructures, at any scale from single workstations to high throughput computing architectures. The Docker Hub is a public registry which can be used to distribute bioinformatic software as Docker images. However, its lack of curation and its genericity make it difficult for a bioinformatics user to find the most appropriate images needed. BioShaDock is a bioinformatics-focused Docker registry, which provides a local and fully controlled environment to build and publish bioinformatic software as portable Docker images. It provides a number of improvements over the base Docker registry on authentication and permissions management, that enable its integration in existing bioinformatic infrastructures such as computing platforms. The metadata associated with the registered images are domain-centric, including for instance concepts defined in the EDAM ontology, a shared and structured vocabulary of commonly used terms in bioinformatics. The registry also includes user defined tags to facilitate its discovery, as well as a link to the tool description in the ELIXIR registry if it already exists. If it does not, the BioShaDock registry will synchronize with the registry to create a new description in the Elixir registry, based on the BioShaDock entry metadata. This link will help users get more information on the tool such as its EDAM operations, input and output types. This allows integration with the ELIXIR Tools and Data Services Registry, thus providing the appropriate visibility of such images to the bioinformatics community.

  8. Metal complexes of salicylhydroxamic acid (H2Sha), anthranilic hydroxamic acid and benzohydroxamic acid. Crystal and molecular structure of [Cu(phen)2(Cl)]Cl x H2Sha, a model for a peroxidase-inhibitor complex.

    Science.gov (United States)

    O'Brien, E C; Farkas, E; Gil, M J; Fitzgerald, D; Castineras, A; Nolan, K B

    2000-04-01

    Stability constants of iron(III), copper(II), nickel(II) and zinc(II) complexes of salicylhydroxamic acid (H2Sha), anthranilic hydroxamic acid (HAha) and benzohydroxamic acid (HBha) have been determined at 25.0 degrees C, I=0.2 mol dm(-3) KCl in aqueous solution. The complex stability order, iron(III) > copper(II) > nickel(II) approximately = zinc(II) was observed whilst complexes of H2Sha were found to be more stable than those of the other two ligands. In the preparation of ternary metal ion complexes of these ligands and 1,10-phenanthroline (phen) the crystalline complex [Cu(phen)2(Cl)]Cl x H2Sha was obtained and its crystal structure determined. This complex is a model for hydroxamate-peroxidase inhibitor interactions.

  9. Characterization of biocomposites of sheep hydroxyapatite (SHA)/shellac/sugar as bone filler material

    Science.gov (United States)

    Triyono, Joko; Rizha, Yushak; Triyono, Teguh

    2018-04-01

    The use of biomaterials in orthopedics is increasing. This led to the growth of innovations in the field of medicine, one of them is the development of biomaterials. Study of Sheep Hydroxyapatite (SHA)/shellac/sugar biocomposite characterization was to determine the phase of the material, porosity, hardness and compressive strength of them. This research was conducted to develop new types of biomaterials that can be used as bone filler material. The analysis that used in this research was dry methods. The results showed that observation of XRD (X-Ray Diffraction) shows the pattern of diffraction 2θ: 31.6472°, 32.7753°, 32.0723°, The highest hardness of SHA/shellac/sugar ratio was 70:30% (7.38±0.1395 VHN) and the lowest at 50:50% (4.91±0.37 VHN). The highest Diametral Tensile Strength (DTS) test was 70:30% (5.43±1.395 MPa) and the lowest at 50:50% (3.10±0.26 MPa). SEM observations are performed to see the material porosity.

  10. Dealing with completeness, structural hierarchy, and seismic coupling issues: three major challenges for #Fault2SHA

    Science.gov (United States)

    Valensise, Gianluca; Barba, Salvatore; Basili, Roberto; Bonini, Lorenzo; Burrato, Pierfrancesco; Carafa, Michele; Kastelic, Vanja; Fracassi, Umberto; Maesano, Francesco Emanuele; Tarabusi, Gabriele; Tiberti, Mara Monica; Vannoli, Paola

    2016-04-01

    The vast majority of active faulting studies are performed at the scale of individual, presumably seismogenic faults or fault strands. Most SHA approaches and models, however, require homogeneus information on potential earthquake sources over the entire tectonic domain encompassing the site(s) of interest. Although it is out of question that accurate SHA must rely on robust investigations of individual potential earthquake sources, it is only by gathering this information in regionally extensive databases that one can address some of the most outstanding issues in the use of #Fault2SHA. We will briefly recall three issues that are particularly relevant in the investigation of seismogenic faulting in southern Europe. A fundamental challenge is the completeness of the geologic record of active faulting. In most tectonic environments many potential seismogenic faults are blind or hidden, or deform the lower crust without leaving a discernible signal at the surface, or occur offshore, or slip so slowly that nontectonic erosional-depositional processes easily outpace their surface effects. Investigating only well-expressed faults is scientifically rewarding but also potentially misleading as it draws attention on the least insidious faults, leading to a potential underestimation of the regional earthquake potential. A further issue concerns the hierarchy of fault systems. Most active faults do not comprise seismogenic sources per se but are part of larger systems, and slip only in conjunction with the master fault of each system. In the most insidious cases, only secondary faults are expressed at the surface while the master fault lies hidden beneath them. This may result in an overestimation of the true number of seismogenic sources that occur in each region and in a biased identification of the characteristics of the main player in each system. Recent investigations of geologic and geodetic vs earthquake release budgets have shown that the "seismic coupling", which

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

    DEFF Research Database (Denmark)

    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...... function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card...... implementations of some of the recently proposed MAC alternatives to NMAC (a fully analyzed variant of HMAC) and HMAC algorithms and NMAC/HMAC versions of some recently proposed hash and compression function modes. We show that the recently proposed BNMAC and KMDP MAC schemes are even weaker than NMAC...

  12. A high speed low power low offset dynamic comparator used in SHA-less pipelined ADC

    Science.gov (United States)

    Shubin, Liu; Zhangming, Zhu; Yintang, Yang; Lianxi, Liu

    2014-05-01

    A novel fully differential high speed high resolution low offset CMOS dynamic comparator has been implemented in the SMIC 0.18 μm process used for a sample-and-hold amplifier (SHA)-less pipelined analog-to-digital converters (ADC). Based on the analysis and optimization between delay time and offset, an enhanced reset architecture with transmission gate was introduced to speed up the comparison and reset procedure. Four inputs with two cross coupled differential pairs, reconstituted bias circuit for tail current transistor and common centroid layouts make the comparator more robust against mismatch and process variations. The simulation results demonstrate that the proposed design achieves 1 mV sensitivity at 2.2 GHz sampling rate with a power consumption of 510 μW, while the mean offset voltage is equal to 10.244 mV.

  13. Roles of putative sodium-hydrogen antiporter (SHA) genes in S. coelicolor A3(2) culture with pH variation.

    Science.gov (United States)

    Kim, Yoon Jung; Moon, Myung Hee; Lee, Jae Sun; Hong, Soon-Kwang; Chang, Yong Keun

    2011-09-01

    Culture pH change has some important roles in signal transduction and secondary metabolism. We have already reported that acidic pH shock enhanced actinorhodin production in Streptomyces coelicolor. Among many potential governing factors on pH variation, the putative Na(+)/H(+) antiporter (sha) genes in S. coelicolor have been investigated in this study to elucidate the association of the sha on pH variation and secondary metabolism. Through the transcriptional analysis and overexpression experiments on 8 sha genes, we observed that most of the sha expressions were promoted by pH shock, and in the opposite way the pH changes and actinorhodin production were enhanced by the overexpression of each sha. We also confirmed that sha8 especially has a main role in maintaining cell viability and pH homeostasis through Na(+) extrusion, in salt effect experiment under the alkaline medium condition by deleting sha8. Moreover, this gene was observed to have a function of pH recovery after pH variation such as the pH shock, being able to cause the sporulation. However, actinorhodin production was not induced by the only pH recovery. The sha8 gene could confer on the host cell the ability to recover pH to the neutral level after pH variation like a pH drop. Sporulation was closely associated with this pH recovery caused by the action of sha8, whereas actinorhodin production was not due to such pH variation patterns alone.

  14. Re-investigation of slip rate along the southern part of the Sumatran Fault Zone using SuMo GPS network

    Science.gov (United States)

    Hermawan, I.; Lubis, A. M.; Sahputra, R.; Hill, E.; Sieh, K.; Feng, L.; Salman, R.; Hananto, N.

    2015-12-01

    The Sumatran Fault Zone (SFZ) accommodates a significant component of the strike-slip motion of oblique convergence along the Sumatra subduction zone. Previous studies have suggested that the slip rates of the SFZ increase from south to north. However, recent work shows that the slip rates may not vary along the SFZ [Bradley et al., 2015]. New data are needed to help confirm these results, and to assess slip-rate variability and fault segmentation in more detail. This information is vital for seismic hazard assessment for the region. We have therefore installed and operated the SuMo (Sumatran Fault Monitoring) network, a dense GPS campaign network focused around the SFZ. From 2013-2015 we selected and installed 32 GPS monuments over the southern part of the SFZ. The network comprises of three transects. The first transect is around the location of the great 1900 earthquake, at the Musi segment. Two transects cover the Manna segment, which saw its last great earthquake in 1893, and the Kumering segment, which saw two great earthquakes in 1933 (M 7.5) and 1994 (M 7.0). We have now conducted three GPS campaign surveys for these stations (3-4 days of measurement for each occupation site), and established 5 semi-permanent cGPS stations in the area. The processed data show that the campaigns sites are still too premature to be used for estimating slip rates, but from the preliminary results for the semi-permanent stations we may see our first signal of deformation. More data from future survey campaigns will help us to estimated revised slip rates. In addition to the science goals for our project, we are this year starting a project called "SuMo Goes to School," which will aim to disseminate information on our science to the schools that house the SuMo GPS stations. The SuMo project also achieves capacity building by training students from Bengkulu University in geodesy and campaign GPS survey techniques.

  15. NeMO-Net & Fluid Lensing: The Neural Multi-Modal Observation & Training Network for Global Coral Reef Assessment Using Fluid Lensing Augmentation of NASA EOS Data

    Science.gov (United States)

    Chirayath, Ved

    2018-01-01

    We present preliminary results from NASA NeMO-Net, the first neural multi-modal observation and training network for global coral reef assessment. NeMO-Net is an open-source deep convolutional neural network (CNN) and interactive active learning training software in development which will assess the present and past dynamics of coral reef ecosystems. NeMO-Net exploits active learning and data fusion of mm-scale remotely sensed 3D images of coral reefs captured using fluid lensing with the NASA FluidCam instrument, presently the highest-resolution remote sensing benthic imaging technology capable of removing ocean wave distortion, as well as hyperspectral airborne remote sensing data from the ongoing NASA CORAL mission and lower-resolution satellite data to determine coral reef ecosystem makeup globally at unprecedented spatial and temporal scales. Aquatic ecosystems, particularly coral reefs, remain quantitatively misrepresented by low-resolution remote sensing as a result of refractive distortion from ocean waves, optical attenuation, and remoteness. Machine learning classification of coral reefs using FluidCam mm-scale 3D data show that present satellite and airborne remote sensing techniques poorly characterize coral reef percent living cover, morphology type, and species breakdown at the mm, cm, and meter scales. Indeed, current global assessments of coral reef cover and morphology classification based on km-scale satellite data alone can suffer from segmentation errors greater than 40%, capable of change detection only on yearly temporal scales and decameter spatial scales, significantly hindering our understanding of patterns and processes in marine biodiversity at a time when these ecosystems are experiencing unprecedented anthropogenic pressures, ocean acidification, and sea surface temperature rise. NeMO-Net leverages our augmented machine learning algorithm that demonstrates data fusion of regional FluidCam (mm, cm-scale) airborne remote sensing with

  16. 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.

  17. Design Approach and Implementation of Application Specific Instruction Set Processor for SHA-3 BLAKE Algorithm

    Science.gov (United States)

    Zhang, Yuli; Han, Jun; Weng, Xinqian; He, Zhongzhu; Zeng, Xiaoyang

    This paper presents an Application Specific Instruction-set Processor (ASIP) for the SHA-3 BLAKE algorithm family by instruction set extensions (ISE) from an RISC (reduced instruction set computer) processor. With a design space exploration for this ASIP to increase the performance and reduce the area cost, we accomplish an efficient hardware and software implementation of BLAKE algorithm. The special instructions and their well-matched hardware function unit improve the calculation of the key section of the algorithm, namely G-functions. Also, relaxing the time constraint of the special function unit can decrease its hardware cost, while keeping the high data throughput of the processor. Evaluation results reveal the ASIP achieves 335Mbps and 176Mbps for BLAKE-256 and BLAKE-512. The extra area cost is only 8.06k equivalent gates. The proposed ASIP outperforms several software approaches on various platforms in cycle per byte. In fact, both high throughput and low hardware cost achieved by this programmable processor are comparable to that of ASIC implementations.

  18. Artificial neural network analysis of RBS data with roughness: Application to Ti{sub 0.4}Al{sub 0.6}N/Mo multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Oehl, G.; Matias, V.; Vieira, A.; Barradas, N.P. E-mail: nunoni@itn.mces.pt

    2003-10-01

    In multilayered Ti{sub 0.4}Al{sub 0.6}N/Mo coatings, a strengthening effect can be obtained by using alternate layers of materials with high and low elastic constants. This behaviour requires a multilayer periodicity below a certain value in order to reduce dislocation motion across layer interface. Below this critical period, in most cases the hardness decreases as the period decreases. The multiple interfaces have an important role on this behaviour, working as stress relaxation areas and preventing crack propagation, influencing the mechanical properties of the system. Understanding the origin of these effects requires knowledge of the interface structure, where the interfacial roughness is of prime importance. We used Rutherford backscattering to study roughness in a quantitative way, and developed an artificial neural network algorithm dedicated to the analysis of the data. The results compare very well with previous TEM and AFM data.

  19. BioShaDock: a community driven bioinformatics shared Docker-based tools registry [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    François Moreews

    2015-12-01

    Full Text Available Linux container technologies, as represented by Docker, provide an alternative to complex and time-consuming installation processes needed for scientific software. The ease of deployment and the process isolation they enable, as well as the reproducibility they permit across environments and versions, are among the qualities that make them interesting candidates for the construction of bioinformatic infrastructures, at any scale from single workstations to high throughput computing architectures. The Docker Hub is a public registry which can be used to distribute bioinformatic software as Docker images. However, its lack of curation and its genericity make it difficult for a bioinformatics user to find the most appropriate images needed. BioShaDock is a bioinformatics-focused Docker registry, which provides a local and fully controlled environment to build and publish bioinformatic software as portable Docker images. It provides a number of improvements over the base Docker registry on authentication and permissions management, that enable its integration in existing bioinformatic infrastructures such as computing platforms. The metadata associated with the registered images are domain-centric, including for instance concepts defined in the EDAM ontology, a shared and structured vocabulary of commonly used terms in bioinformatics. The registry also includes user defined tags to facilitate its discovery, as well as a link to the tool description in the ELIXIR registry if it already exists. If it does not, the BioShaDock registry will synchronize with the registry to create a new description in the Elixir registry, based on the BioShaDock entry metadata. This link will help users get more information on the tool such as its EDAM operations, input and output types. This allows integration with the ELIXIR Tools and Data Services Registry, thus providing the appropriate visibility of such images to the bioinformatics community.

  20. A geochemical evaluation of the Ash Sha'ib mineral prospect, Asir quadrangle, Kingdom of Saudi Arabia

    Science.gov (United States)

    Allcott, Glenn H.

    1970-01-01

    The mineralized zone at the remotely located Ash Sha'ib ancient mine contains only a small tonnage of moderately low grade sulfide- bearing rock. Based on present data the gross value of the deposit, with a value of $25.00 or more per ton, is $20,000,000. A belt of metasedimentary rocks, intruded by gabbro to the south and granite to the north, was the host for fissure vein-replacement type mineralization. Most of the mineralization is in a siliceous dolomite transected by fissures. The main sulfide mineral is sphalerite, but minor amounts of chalcopyrlte and argentlferous galena contribute to the value of the mineralized sections.

  1. 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

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

    International Nuclear Information System (INIS)

    Seuntjens, J; Collins, L; Devic, S; El Naqa, I; Nadeau, J; Reader, A; Beaulieu, L; Despres, P; Pike, B

    2015-01-01

    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

  3. 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

  4. Theatre as a Vortex of Behaviour in Dutch Multicultural Society: A Discourse Analysis of "Aïsha" in the Public Sphere

    NARCIS (Netherlands)

    van Heugten, L.

    2013-01-01

    In 2001, a music theatre production exploring Islam’s early history from a female perspective was shut down before it reached the stage. The cancellation of Aïsha and the Women of Madina by Rotterdam’s Independent Theatre (O.T.) generated a media storm as speculations about censorship mounted. To

  5. 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%.

  6. Ni nanoparticles@Ni-Mo nitride nanorod arrays: a novel 3D-network hierarchical structure for high areal capacitance hybrid supercapacitors.

    Science.gov (United States)

    Ruan, Yunjun; Lv, Lin; Li, Zhishan; Wang, Chundong; Jiang, Jianjun

    2017-11-23

    Because of the advanced nature of their high power density, fast charge/discharge time, excellent cycling stability, and safety, supercapacitors have attracted intensive attention for large-scale applications. Nevertheless, one of the obstacles for their further development is their low energy density caused by sluggish redox reaction kinetics, low electroactive electrode materials, and/or high internal resistance. Here, we develop a facile and simple nitridation process to successfully synthesize hierarchical Ni nanoparticle decorated Ni 0.2 Mo 0.8 N nanorod arrays on a nickel foam (Ni-Mo-N NRA/NF) from its NiMoO 4 precursor, which delivers a high areal capacity of 2446 mC cm -2 at a current density of 2 mA cm -2 and shows outstanding cycling stability. The superior performance of the Ni-Mo-N NRA/NF can be ascribed to the metallic conductive nature of the Ni-Mo nitride, the fast surface redox reactions for the electrolyte ions and electrode materials, and the low contacted resistance between the active materials and the current collectors. Furthermore, a hybrid supercapacitor (HSC) is assembled using the Ni-Mo-N NRA/NF as the positive electrode and reduced graphene oxide (RGO) as the negative electrode. The optimized HSC exhibits excellent electrochemical performance with a high energy density of 40.9 W h kg -1 at a power density of 773 W kg -1 and a retention of 80.1% specific capacitance after 6000 cycles. These results indicate that the Ni-Mo-N NRA/NF have a promising potential for use in high-performance supercapacitors.

  7. CoMo sulphide-catalyzed hydrodeoxygenation of lignin model compounds: An extended reaction network for the conversion of monomeric and dimeric substrates

    NARCIS (Netherlands)

    Jongerius, A.L.; Jastrzebski, R; Bruijnincx, P.C.A.; Weckhuysen, B.M.

    2012-01-01

    In the present work, extensive hydrodeoxygenation (HDO) studies with a commercial sulfided CoMo/Al2O3 catalyst were performed on a library of ligninmodel compounds at 50 bar hydrogen pressure and 300 °C in dodecane, using a batch autoclave system. The catalyst was activated under hydrogen atmosphere

  8. Synthesis, structure and optical properties of two isotypic crystals, Na3MO4Cl (M=W, Mo)

    International Nuclear Information System (INIS)

    Han, Shujuan; Bai, Chunyan; Zhang, Bingbing; Yang, Zhihua; Pan, Shilie

    2016-01-01

    Two isotypic compounds, Na 3 MO 4 Cl (M = W, Mo) have been obtained from the high temperature solution, and their structures were determined by single-crystal X-ray diffraction. Both of them crystallize in the space group P4/nmm of tetragonal system with the unit cells: a=7.5181(15), c=5.360(2) for Na 3 WO 4 Cl and a=7.4942(12), c=5.3409(18) for Na 3 MoO 4 Cl. The structure exhibits a 3D network built up by the ClNa 6 groups, and the MO 4 groups reside in the tunnels of the 3D network. The structural similarities and differences between Na 3 MO 4 Cl (M=W, Mo) and Sr 3 MO 4 F (M=Al, Ga) have been discussed. Meanwhile, detailed structure comparison analyses between Na 3 MO 4 Cl (M=W, Mo) and Na 3 MO 4 F (M=W, Mo) indicate that the different connection modes of ClNa 6 and FNa 6 make Na 3 MO 4 Cl and Na 3 MO 4 F crystallize in different structures. The IR spectra were used to verify the validity of the structure. The diffuse reflectance spectra show that the UV absorption edges are about 249 nm (4.99 eV) and 265 nm (4.69 eV) for Na 3 WO 4 Cl and Na 3 MoO 4 Cl, respectively. In addition, the first-principles theoretical studies are also carried out to aid the understanding of electronic structures and linear optical properties. - Graphical abstract: Two isotypic compounds, Na 3 MO 4 Cl (M=W, Mo) have been obtained from the high temperature solution. Both of them crystallize in the space group P4/nmm of tetragonal system. The structure exhibits a 3D network built up by the ClNa 6 groups, and the MO 4 groups reside in the tunnels of the 3D network. - Highlights: • Structure and properties of Na 3 MO 4 Cl (M=W, Mo) are reported for the first time. • They show a 3D network built by ClNa 6 , and WO 4 lies in the tunnels of the network. • IR spectra were used to verify the validity of the structure. • Band structures and density of states have been calculated.

  9. 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.

  10. 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.

  11. 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.

  12. 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)

  13. Nodal head method with matric operation in analysis of mine ventilation networks. Matrics kaiho wo mochiita setten ho ni yoru tsuki mo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, K.; Miyakoshi, H. (Akita Univ., Akita (Japan). Mining College); Kinoshita, H.; Onozuka, T. (Hanaoka Mining Co. Ltd., Akita (Japan))

    1990-09-25

    In this report, the method of analyzing mine ventilation networks is explained in which the direct matric operation method is applied to the solution of the linear equation system introduced from the fundamental equation of the nodal head method. In other words, the fundamental equation was expressed by genelarized equation composition by using connecting functions between nodes and the algorism of a computer program was clarified. And the calculation method necessary for other ventilation netwrks analysis was shown in a concrete form. For solving the linear equation system, the matric operation method based on the modified Choleski's method was used in order to speed up the calculation and stabilize the convergence process of the solution. As examples, calculation was made on the ventilation networks of total numbers of the nodes of 8, 14, 51 and 141. From these ventilation network analyses, using a linear equation system concerning the nodal pressure correction, it was found that in the system with convergence acceleration coefficient of 1.4, the number of sequential repeating frequency of approximation Mc which was required for convergence was in the order of Mc {approx equal} 13 (cycle) for the condition that the fan pressure was constant and the convergence condition was {vert bar} AQi {vert bar}{sub max} {lt} 0.1m {sup 3}/min. 14 refs., 12 figs., 3 tabs.

  14. Study of transmitting electric power utility communications in IP network. Transmission of existing electric power utility communications in best effort type IP network under delay constraint; Denryokuyo tsushin kaisen no IP mo eno shuyo kento. Chien jikan seiyakuka ni okeru best effort gata IP mo eno kison denryokuyo tsushin kaisen no shuyo

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, H.

    2000-07-01

    Since IP network does best effort behavior fundamentally, it always generates delay time and delay variation. For this reason, IP network has been unsuitable to transmit real time data such as a voice. However, in recent years, the technologies which transmit real time data in IP network, e.g. VoIP, have spread. If it is possible to transmit the existing electric power utility communications in IP network using these technologies, total network cost can be reduced by the reduction of required bandwidth and the simplification of communication network systems. In this report, it is examined quantitatively whether end-end delay time of the existing electric power utility communications, e.g. on-line, telephone, carrier relay, CDT (cyclic digital transmission equipment), video conference, ITV(industrial television), is within their permission delay time when they are transmitted in the best effort type IP network. (author)

  15. Decay of 99Mo

    International Nuclear Information System (INIS)

    Dickens, J.K.; Love, T.A.

    1976-01-01

    Relative intensities for K x-rays and gamma rays emanating from 99 Mo in equilibrium with its 99 Tc* daughter have been measured using several Ge photon detectors. Combining these intensities with an evaluated set of electron-conversion coefficients has provided a set of absolute intensities for the observed gamma rays. The absolute intensity for the dominant 140.5-keV gamma ray in 99 Tc was determined to be 90.7 +- 0.6/100 99 Mo disintegrations for 99 Mo decay in equilibrium with decay of the 99 Tc* daughter

  16. 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...

  17. Antioxidant effects of betulin on porcine chondrocyte behavior in gelatin/C6S/C4S/HA modified tricopolymer scaffold

    International Nuclear Information System (INIS)

    Lin, Wen-Yang; Lin, Feng-Huei; Sadhasivam, S.; Savitha, S.

    2010-01-01

    The antioxidant effects of betulin on porcine chondrocytes cultured in gelatin/C6S/C4S/HA modified tricopolymer scaffold for a period of 4 weeks was investigated. The porous structure of the scaffold and cell attachment was observed by scanning electron microscopy (SEM). Biochemical measures of necrosis, cell proliferation, sulfated glycosaminoglycans (sGAG) content and extracellular matrix related gene expressions were quantitatively evaluated. The cell proliferation data showed good cellular viability in tricopolymer scaffold and increased optical density for total DNA demonstrated that the cells continued to proliferate inside the scaffold. The sGAG production indicated chondrogenic differentiation. Chondrocytes treated with betulin expressed transcripts encoding type II collagen, aggrecan, and decorin. To conclude, the substantiated results supported cell proliferation, production of extracellular matrix proteins and down-regulation of matrix metalloproteases and cytokine, in betulin treated scaffolds.

  18. Antioxidant effects of betulin on porcine chondrocyte behavior in gelatin/C6S/C4S/HA modified tricopolymer scaffold

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Wen-Yang; Lin, Feng-Huei [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China); Sadhasivam, S., E-mail: rahulsbio@yahoo.co.in [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China); Savitha, S. [Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan (China)

    2010-05-10

    The antioxidant effects of betulin on porcine chondrocytes cultured in gelatin/C6S/C4S/HA modified tricopolymer scaffold for a period of 4 weeks was investigated. The porous structure of the scaffold and cell attachment was observed by scanning electron microscopy (SEM). Biochemical measures of necrosis, cell proliferation, sulfated glycosaminoglycans (sGAG) content and extracellular matrix related gene expressions were quantitatively evaluated. The cell proliferation data showed good cellular viability in tricopolymer scaffold and increased optical density for total DNA demonstrated that the cells continued to proliferate inside the scaffold. The sGAG production indicated chondrogenic differentiation. Chondrocytes treated with betulin expressed transcripts encoding type II collagen, aggrecan, and decorin. To conclude, the substantiated results supported cell proliferation, production of extracellular matrix proteins and down-regulation of matrix metalloproteases and cytokine, in betulin treated scaffolds.

  19. 99Mo production by 100Mo(n,2n)99Mo using accelerator neutrons

    International Nuclear Information System (INIS)

    Sato, Nozomi; Kawabata, Masako; Nagai, Yasuki; Hashimoto, Kazuyuki; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Kin, Tadahiro; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Minato, Futoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Hashimoto, Shintaro

    2013-01-01

    We proposed a new route to produce a medical radioisotope 99 Mo by the 100 Mo(n,2n) 99 Mo reaction using accelerator neutrons. A high-quality 99 Mo with a minimum level of radioactive waste can be obtained by the proposed reaction. The decay product of 99 Mo, 99m Tc, is separated from 99 Mo by the sublimation method. The proposed route could bring a major breakthrough in the solution of ensuring a constant and reliable supply of 99 Mo. (author)

  20. Internet application: production-technical information system MoNET

    International Nuclear Information System (INIS)

    Tomiga, J.

    2004-01-01

    MoNET is the production-technical information system supporting engineering, operational and maintenance processes of distribution network administrator. It utilizes the model of distribution network that is situated in the geo-space relational database. The geo-space database represents an information base of operational-technical processes. It contains elements and equipment s of the distribution network, failures, operational events, maintenance records, but also, parcels, reference planimetry, e.g. and other subjects for which is relevant the positional datum - geo-space information. MoNET is typically exploited in the fields: - evidence of the subjects and equipment of network, technical documentation; - property administration; - planning of network development, support of designing and construction; - technical calculation; - breakdown controller centre; - maintenance management. MoNET can be implemented as the desktop application, however its first benefit is derived from its usage as the intranet application MoNET WEB for the whole enterprise or organisation. This version enables an unrestricted number of end-users to enter this system. The end-users don't need any special software to enter the data of MoNet WEB application, the pre-installed Internet Explorer will do. (author)

  1. Networking

    OpenAIRE

    Rauno Lindholm, Daniel; Boisen Devantier, Lykke; Nyborg, Karoline Lykke; Høgsbro, Andreas; Fries, de; Skovlund, Louise

    2016-01-01

    The purpose of this project was to examine what influencing factor that has had an impact on the presumed increasement of the use of networking among academics on the labour market and how it is expressed. On the basis of the influence from globalization on the labour market it can be concluded that the globalization has transformed the labour market into a market based on the organization of networks. In this new organization there is a greater emphasis on employees having social qualificati...

  2. Preliminary analysis of the sandstone accumulation situation at Sha-3 of the Paleogene Series Shakhetsze in the Khekou basin of the Tsziyan region

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S

    1984-01-01

    The Khekou basin of the second order which is located in the Eastern part of the Tsziyan basin in the oil and gas Bokhayvan'skiy pool has an area of about 900 km/sup 2/. The main productive level occurs in sandstone beds in the Sha-3 subseries (reaching thickness of about 400 m) of the Shakhetsze series. The Bonan oil field was discovered in this region in 1975. The initially productive deposits were viewed as fluvial-delta; however, studies of recent years, including investigation of the sedimentation sequences and the structures that mark the surfaces of the microscopic level in the core sample, together with an analysis of borehole geophysical data, indicated that the sandy bodies of the productive beds in the basin must be viewed as deposits of turbidite flows and deposits of gravitational flows in channels. Insofar as distribution of the turbidite sandstones differs significantly from the delta, this led to a review of the long-term trends in the neighboring fields.

  3. RoMo

    DEFF Research Database (Denmark)

    Pedersen, Esben Warming; Hornbæk, Kasper

    2011-01-01

    In TUIs, physical/digital conflicts can occur when the digital model does not match the model implied by the spatial lay- out of tangibles. We show how tangible tabletop interfaces (TTI) can be modified to allow robot movement of tangi- bles, thereby avoiding conflicts. We present RoMo, an open...... source Java library that allow existing TTI applications to perform robot movement, and demonstrate its functionality with three applications....

  4. MoCha: Molecular Characterization of Unknown Pathways.

    Science.gov (United States)

    Lobo, Daniel; Hammelman, Jennifer; Levin, Michael

    2016-04-01

    Automated methods for the reverse-engineering of complex regulatory networks are paving the way for the inference of mechanistic comprehensive models directly from experimental data. These novel methods can infer not only the relations and parameters of the known molecules defined in their input datasets, but also unknown components and pathways identified as necessary by the automated algorithms. Identifying the molecular nature of these unknown components is a crucial step for making testable predictions and experimentally validating the models, yet no specific and efficient tools exist to aid in this process. To this end, we present here MoCha (Molecular Characterization), a tool optimized for the search of unknown proteins and their pathways from a given set of known interacting proteins. MoCha uses the comprehensive dataset of protein-protein interactions provided by the STRING database, which currently includes more than a billion interactions from over 2,000 organisms. MoCha is highly optimized, performing typical searches within seconds. We demonstrate the use of MoCha with the characterization of unknown components from reverse-engineered models from the literature. MoCha is useful for working on network models by hand or as a downstream step of a model inference engine workflow and represents a valuable and efficient tool for the characterization of unknown pathways using known data from thousands of organisms. MoCha and its source code are freely available online under the GPLv3 license.

  5. Diffusion barrier performances of thin Mo, Mo-N and Mo/Mo-N films between Cu and Si

    International Nuclear Information System (INIS)

    Song Shuangxi; Liu Yuzhang; Mao Dali; Ling Huiqin; Li Ming

    2005-01-01

    In this work, we have studied the diffusion barrier performances of Mo, Mo-N and Mo/Mo-N metallization layers deposited by sputtering Mo in Ar/N 2 atmospheres, respectively. Samples were subsequently annealed at different temperatures ranging from 400 to 800 deg C in vacuum condition. The film properties and their suitability as diffusion barriers and protective coatings in silicon devices were characterized using four-point probe measurement, X-ray diffractometry, scanning electron microscopy, Auger electron spectroscopy and transmission electron microscopy analyses. Experimental results revealed that the Mo (20 nm)/Mo-N (30 nm) layer was able to prevent the diffusion reaction between Cu and Si substrate after being annealed at 600 deg C for 30 min. The adhesion between layers and the content of N atoms are the key parameters to improve the properties of Mo-based barrier materials. The Mo layer interposed between Cu and Mo-N diluted the high nitrogen concentration of the barrier and so enhanced the barrier performances

  6. MoMoSat -- Mobile Service for Monitoring with GeoNotes via Satellite

    Energy Technology Data Exchange (ETDEWEB)

    Niemeyer, Irmgard [Forschungszentrum Juelich (Germany). Programme Group Systems Analysis and Technology Evaluation (STE); Jonas, Karl [Univ. of Applied Science Bonn-Rhein-Sieg, Sankt Augustin (Germany). FhG FOKUS CC SATCom; Horz, Alexander [horz informatik, Sankt Augustin (Germany); Wettschereck, Dietrich; Schmidt, Dirk [DIALOGIS GmbH, Bonn (Germany)

    2003-05-01

    The MoMoSat service will enable mobile end-users to view, manage, annotate, and communicate mapbased information in the field. The handled information exists of a huge volume of raster (satellite or aerial images) and vector data (i.e. street networks, cadastral maps or points of interest), as well as text-specific geo-referenced textual notes (the so-called 'GeoNotes') and real-time voice. A secure real-time communication between mobile units and the primary data store is an essential task of the MoMoSat service. The basic information is stored in the primary database that is accessible through a virtual private network (VPN) and cached at a server at a base station in order to ensure data availability. The base station may be installed in a car or another mobile vehicle. The two servers will periodically communicate with each other via secure satellite communication in order to check for updates. The base station supplies the relevant GIS data for the mobile units (people or even robots in the field at remote solutions). The communication between the mobile units is based on a peer-to-peer wireless local area network (WLAN) architecture. The mobile units are equipped with mobile computers (i.e. laptop, tablet PC or PDA) combined with a satellite-based positioning system (GPS) that enables them to request the proper geographic data sets from yhe base station's map server. An interactive mapping software shows the actual location on the map and allows the user to navigate (zoom, pan) through the high-resolution map display. The user can switch 'on' or 'off' several thematic layers (i.e. street network or points of interest) on the map. The software also supports collaborative aspects of MoMoSat by offering tools for the management of the GeoNotes that can be visualized by categories. The user can extend the existing GeoNotes with his personnel comments or create new GeoNotes by defining categories, recipients and the level of

  7. Microstructure investigation of NiAl-Cr(Mo) interface in a directionally solidified NiAl-Cr(Mo) eutectic alloyed with refractory metal

    International Nuclear Information System (INIS)

    Chen, Y.X.; Cui, C.Y.; Guo, J.T.; Li, D.X.

    2004-01-01

    The microstructure of a directionally solidified NiAl-Cr(Mo) eutectic alloyed with refractory metal in as-processed and heat-treated states has been studied by means of scanning electron microscopy and high resolution electron microscopy (HREM). The microstructure of the NiAl-Cr(Mo) eutectic was characterized by lamellar Cr(Mo) phases embedded within NiAl matrix with common growth direction of . The interface between NiAl and lamellar Cr(Mo) did not have any transition layers. Misfit dislocations were observed at the NiAl-Cr(Mo) interface. In addition to lamellar Cr(Mo) phases, coherent Cr(Mo, Ni, Al) precipitates and NiAl precipitates were also observed in the NiAl matrix and lamellar Cr(Mo) phases, respectively. After hot isostatic pressing and heat treatment, the NiAl-Cr(Mo) interfaces became smooth and straight. Square array of misfit dislocations was directly observed at the (0 0 1) interface between NiAl and Cr(Mo, Ni, Al) precipitate. The configuration of misfit dislocation network showed a generally good agreement with prediction based on the geometric O-lattice model

  8. 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) .

  9. 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 :...

  10. Fission 99Mo production technology

    International Nuclear Information System (INIS)

    Miao Zengxing; Luo Zhifu; Ma Huimin; Liang Yufu; Yu Ningwen

    2003-01-01

    This paper describes a production technology of fission 99 Mo in the Department Isotope, CIAE. The irradiation target is tubular U-Al alloy containing highly enriched uranium. The target is irradiated in the swimming pool reactor core. The neutron flux is about 4x10 13 /cm 2 .sec. The production scale is 3.7-7.4 TBq (100-200Ci) of fission 99 Mo per batch. Total recovery of 99 Mo is more than 70%. The production practice proves that the process and equipment are safe and reliable. (author)

  11. 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.

  12. Preparation of MoB and MoB-MoSi2 composites by combustion synthesis in SHS mode

    International Nuclear Information System (INIS)

    Yeh, C.L.; Hsu, W.S.

    2007-01-01

    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 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 α-MoB from the Mo-B sample at equiatomic stoichiometry. In the synthesis of MoB-MoSi 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 2 composite through the SHS reaction; that is, in addition to a small amount of Mo 5 Si 3 , the as-synthesized composite is composed entirely of MoB and MoSi 2

  13. 99Mo Yield Using Large Sample Mass of MoO3 for Sustainable Production of 99Mo

    Science.gov (United States)

    Tsukada, Kazuaki; Nagai, Yasuki; Hashimoto, Kazuyuki; Kawabata, Masako; Minato, Futoshi; Saeki, Hideya; Motoishi, Shoji; Itoh, Masatoshi

    2018-04-01

    A neutron source from the C(d,n) reaction has the unique capability of producing medical radioisotopes such as 99Mo with a minimum level of radioactive waste. Precise data on the neutron flux are crucial to determine the best conditions for obtaining the maximum yield of 99Mo. The measured yield of 99Mo produced by the 100Mo(n,2n)99Mo reaction from a large sample mass of MoO3 agrees well with the numerical result estimated with the latest neutron data, which are a factor of two larger than the other existing data. This result establishes an important finding for the domestic production of 99Mo: approximately 50% of the demand for 99Mo in Japan could be met using a 100 g 100MoO3 sample mass with a single accelerator of 40 MeV, 2 mA deuteron beams.

  14. 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.)

  15. Electronic structures of B1 MoN, fcc Mo2N, and hexagonal MoN

    International Nuclear Information System (INIS)

    Ihara, H.; Kimura, Y.; Senzaki, K.; Kezuka, H.; Hirabayashi, M.

    1985-01-01

    The electronic structures of B1 MoN, fcc Mo 2 N, and hexagonal MoN were observed by photoelectron spectroscopic measurement. The B1-MoN phase has been predicted to be a high-T/sub c/ superconductor because of a large density of states at Fermi level. The observed electronic structure of the stoichiometric B1-MoN phase is different from that of the real B1-MoN type. The nitrogen excess B1-MoN/sub x/ (x> or =1.3) phase, however, shows the B1-type electronic structure. This is explained by the occurrence of a nitrogen vacancy in the apparent stoichiometric B1 phase and the occupation of the nitrogen vacancy in the nitrogen-excess B1 phase. This property is related to the previously reported low T/sub c/ of the B1-MoN crystals

  16. In Situ Investigations of Li-MoS2 with Planar Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Jiayu [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Bao, Wenzhong [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering and Dept. of Physics; Liu, Yang [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies (CINT); Dai, Jiaqi [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Shen, Fei [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Zhou, Lihui [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Cai, Xinghan [Univ. of Maryland, College Park, MD (United States). Dept. of Physics; Urban, Daniel [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Li, Yuanyuan [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering; Jungjohann, Katherine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies (CINT); Fuhrer, Michael S. [Univ. of Maryland, College Park, MD (United States). Dept. of Physics; Monash Univ., Melbourne, VIC (Australia). School of Physics; Hu, Liangbing [Univ. of Maryland, College Park, MD (United States). Dept. of Materials Science and Engineering

    2014-11-25

    For this study, a planar microbattery that enables various in situ measurements of lithiation of 2D materials on the individual-flake scale is developed. A large conductivity increase of thick MoS2 crystallite lithiation due to the formation of a percolative Mo nanoparticle network embedded in a Li2S matrix is observed. The nanoscale study leads to the development of a novel charging strategy for batteries that largely improves the capacity and cycling performance confirmed in bulk MoS2/Li coin cells.

  17. Microstructure and properties of MoSi2-MoB and MoSi2-Mo5Si3 molybdenum silicides

    International Nuclear Information System (INIS)

    Schneibel, J.H.; Sekhar, J.A.

    2003-01-01

    MoSi 2 -based intermetallics containing different volume fractions of MoB or Mo 5 Si 3 were fabricated by hot-pressing MoSi 2 , MoB, and Mo 5 Si 3 powders in vacuum. Both classes of alloys contained approximately 5 vol.% of dispersed silica phase. Additions of MoB or Mo 5 Si 3 caused the average grain size to decrease. The decrease in the grain size was typically accompanied by an increase in flexure strength, a decrease in the room temperature fracture toughness, and a decrease in the hot strength (compressive creep strength) measured around 1200 deg. C, except when the Mo 5 Si 3 effectively became the major phase. Oxidation measurements on the two classes of alloys were carried out in air. Both classes of alloys were protected from oxidation by an in-situ adherent scale that formed on exposure to high temperature. The scale, although not analyzed in detail, is commonly recognized in MoSi 2 containing materials as consisting mostly of SiO 2 . The MoB containing materials showed an increase in the scale thickness and the cyclic oxidation rate at 1400 deg. C when compared with pure MoSi 2 . However, in contrast with the pure MoSi 2 material, oxidation at 1400 deg. C began with a weight loss followed by a weight gain and the formation of the protective silica layer. The Mo 5 Si 3 containing materials experienced substantial initial weight losses followed by regions of small weight changes. Overall, the MoB and Mo 5 Si 3 additions to MoSi 2 tended to be detrimental for the mechanical and oxidative properties

  18. 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

    1,2 intercalation assisted exfoliation,8–11 physical vapor deposition (PVD),12,13 and a wet chemistry approach involving thermal decomposition of a... annealed MoO3, MoS2 films S1 (MoS2 using Mo precursor), S2 (MoS2 using MoO3 precursor), S1r (MoS2 using Mo pre- cursor and rGO), and S2r (MoS2 using...MoO3 precursor and rGO). The annealed MoO3 (a) shows Mo(IV) peaks which are indicative of MoO2, and Mo(VI) peaks that occur when MoO3 is present. Both

  19. 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.

  20. 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 ...

  1. 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.

  2. Performance of Group Communication Over Ad-Hoc Networks

    National Research Council Canada - National Science Library

    Mosko, Marc; Garcia-Luna-Aceves, J. J

    2002-01-01

    ... through a network of cluster trees, where a spanning tree joins groups of fully connected nodes. Through numerical analysis and simulations in GloMoSim, we show throughput, goodput, and loss rates for reliable and unreliable networks...

  3. The synthesis of hierarchical nanostructured MoS_2/Graphene composites with enhanced visible-light photo-degradation property

    International Nuclear Information System (INIS)

    Zhao, Yongjie; Zhang, Xiaowei; Wang, Chengzhi; Zhao, Yuzhen; Zhou, Heping; Li, Jingbo; Jin, HaiBo

    2017-01-01

    Graphical abstract: Introducing graphene layer into MoS_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_2 and MoS_2/Graphene nanocomposite have been synthesized via a solvothermal process. • The scrolled nanosheets of MoS_2 combining with interconnected graphene network promoted the formation of steady hierarchical architecture. • Comparing with MoS_2, the hierarchical MoS_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_2 and MoS_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_2, the hierarchical MoS_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_2 and graphene layers. The MoS_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_2 photo-catalyst, and also provide useful information for understanding the observed enhanced photocatalytic mechanism

  4. 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>

  5. Ternary system of Na2MoO4-Cs2MoO4-MoO3

    International Nuclear Information System (INIS)

    Zueva, V.P.; Shabanova, A.N.; Drobasheva, T.I.

    1982-01-01

    Using the methods of thermal analysis interaction of components in ternary system Na 2 MoO 4 -Cs 2 MoO 4 -MoO 3 has been studied. Crystallization surface consists of nine fields belonging to initial components and compounds of lateral sides. Triangulation of the system is carried out and the character of nonvariant points is clarified, the temperature of 360 deg C corresponds to low-melting eutectics

  6. Electronic structure of structural open derivatives of the [Mo6X14]2- cluster: [Mo5Cl13]2- and [Mo4I11]2-

    International Nuclear Information System (INIS)

    Miessner, H.; Korol'kov, D.V.

    1983-01-01

    The electronic structure of structural open derivatives of the [Mo 6 X 14 ] 2 - -cluster [Mo 5 Cl 13 ] 2 - and [Mo 4 I 11 ] 2 - has been studied by the EHMO method. In [Mo 5 Cl 13 ] 2 - 9 occupied MO's with dominant Mo4d character are responsible for the formation of the 8 metal-metal bonds. In [Mo 4 I 11 ] 2 - the stronger covalent character of the Mo-I bonds affects the localization and the energy of molecular orbitals and also the charge distribution. The metal-metal bonds are formed by 8 MO's containing considerable participation of halogen AO's contrary to the chloride cluster. There is no bonding between the Mo atoms at the wing tips of the Mo 4 butterfly and the reason for decreasing the dihedral angle between the Mo 3 planes in [Mo 4 I 11 ] 2 - compared with the octahedral angle is apparently the stabilization of the whole system (Mo-Mo and Mo-I bonds). The unpaired electron occupies in both clusters a slightly antibonding (with regard to the Mo-Mo bonds) orbital. (author)

  7. Creep and shrinkage of Mo(Ni)

    International Nuclear Information System (INIS)

    Kaysser, W.A.; Hofmann-Amtenbrink, M.; Petzow, G.

    1984-01-01

    To avoid some of the errors inherent in a quantitative interpretation of shrinkage of powder compacts as Mo-Ni, other experiments were looked for, where the influence of Ni on the material transport properties of Mo could be measured semi-quantitatively during heating up to temperature and subsequent isothermal annealing. The bending of thin Mo foils under small loads was found to be an experimental arrangement, where variations in stress, in Ni-concentration and in intrinsic material properties could be realized. The results of these creep experiments will be compared in a qualitative sense with sintering experiments in Mo-Ni done under similar conditions as the creep experiments

  8. On the reduction of orthorhombic MoO3 to MoO2

    International Nuclear Information System (INIS)

    Delannay, F.

    1982-01-01

    Electron diffraction shows evidence of topotactic orientation relationships between the original MoO 3 crystal and MoO 2 crystals formed under mild reduction conditions. These relationships differ from previously published literature data. A possible mechanism of formation of the [100] strings of edge sharing octahedra in the MoO 2 structure is tentatively proposed. (author)

  9. Microwave effects on NiMoS and CoMoS single-sheet catalysts.

    Science.gov (United States)

    Borges, I; Silva, Alexander M; Modesto-Costa, Lucas

    2018-05-04

    Single-sheet nanoclusters of MoS 2 , NiMoS or CoMoS are widely used in hydrodesulfurization (HDS) catalysis in the petroleum industry. In HDS reactions under microwave irradiation, experiments indirectly pointed out that for pristine MoS 2 reaction rates are accelerated because hot spots are generated on the catalyst bed. In this work, we investigated NiMoS and CoMoS isolated single-sheet substituted catalysts before and after thiophene adsorption focusing on quantifying the effect of microwave irradiation. For that purpose, density functional theory (DFT) molecular charge densities of each system were decomposed according to the distributed multipole analysis (DMA) of Stone. Site dipole values of each system were directly associated with a larger or smaller interaction with the microwave field according to a proposed general approach. We showed that microwave enhancement of HDS reaction rates can occur more efficiently in the CoMoS and NiMoS promoted clusters compared to pristine MoS 2 in the following order: CoMoS > NiMoS > MoS 2 . The atomic origin of the catalyst hot spots induced by microwaves was clearly established in the promoted clusters.

  10. 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...

  11. Postirradiation tensile properties of Mo and Mo alloys irradiated with 600 MeV protons

    International Nuclear Information System (INIS)

    Mueller, G.V.; Gavillet, D.; Victoria, M.; Martin, J.L.

    1994-01-01

    Tensile specimens of pure Mo and Mo-5 Re, Mo-41 Re and TZM alloys have been irradiated with 600 MeV protons in the PIREX facility at 300 and 660 K to 0.5 dpa. Results of the postirradiation tensile testing show a strong radiation hardening and a severe loss of ductility for all the materials tested at room temperature. ((orig.))

  12. On the Mo-Papas equation

    Science.gov (United States)

    Aguirregabiria, J. M.; Chamorro, A.; Valle, M. A.

    1982-05-01

    A new heuristic derivation of the Mo-Papas equation for charged particles is given. It is shown that this equation cannot be derived for a point particle by closely following Dirac's classical treatment of the problem. The Mo-Papas theory and the Bonnor-Rowe-Marx variable mass dynamics are not compatible.

  13. NASA Communications Augmentation network

    Science.gov (United States)

    Omidyar, Guy C.; Butler, Thomas E.; Laios, Straton C.

    1990-01-01

    The NASA Communications (Nascom) Division of the Mission Operations and Data Systems Directorate (MO&DSD) is to undertake a major initiative to develop the Nascom Augmentation (NAUG) network to achieve its long-range service objectives for operational data transport to support the Space Station Freedom Program, the Earth Observing System (EOS), and other projects. The NAUG is the Nascom ground communications network being developed to accommodate the operational traffic of the mid-1990s and beyond. The NAUG network development will be based on the Open Systems Interconnection Reference Model (OSI-RM). This paper describes the NAUG network architecture, subsystems, topology, and services; addresses issues of internetworking the Nascom network with other elements of the Space Station Information System (SSIS); discusses the operations environment. This paper also notes the areas of related research and presents the current conception of how the network will provide broadband services in 1998.

  14. Enhanced performance of lithium-sulfur batteries with an ultrathin and lightweight MoS2/carbon nanotube interlayer

    Science.gov (United States)

    Yan, Lingjia; Luo, Nannan; Kong, Weibang; Luo, Shu; Wu, Hengcai; Jiang, Kaili; Li, Qunqing; Fan, Shoushan; Duan, Wenhui; Wang, Jiaping

    2018-06-01

    Ultrathin and lightweight MoS2/carbon nanotube (CNT) interlayers are developed to effectively trap polysulfides in high-performance lithium-sulfur (Li-S) batteries. The MoS2/CNT interlayer is constructed by loading MoS2 nanosheets onto a cross-stacked CNT film. The CNT film with excellent conductivity and superior mechanical properties provides the Li-S batteries with a uniform conductive network, a supporting skeleton for the MoS2 nanosheets, as well as a physical barrier for the polysulfides. Moreover, chemical interactions and bonding between the MoS2 nanosheets and the polysulfides are evident. The electrode with the MoS2/CNT interlayer delivers an attractive specific capacity of 784 mA h g-1 at a high capacity rate of 10 C. In addition, the electrode demonstrates a high initial capacity of 1237 mA h g-1 and a capacity fade as low as -0.061% per cycle over 500 charge/discharge cycles at 0.2 C. The problem of self-discharge can also be suppressed with the introduction of the MoS2/CNT interlayer. The simple fabrication procedure, which is suitable for commercialization, and the outstanding electrochemical performance of the cells with the MoS2/CNT interlayer demonstrate a great potential for the development of high-performance Li-S batteries.

  15. Dual functional MoS2/graphene interlayer as an efficient polysulfide barrier for advanced lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Guo, Pengqian; Liu, Dequan; Liu, Zhengjiao; Shang, Xiaonan; Liu, Qiming; He, Deyan

    2017-01-01

    Highlights: •Dual functional MoS 2 /graphene interlayer was first used as an efficient polysulfide-trapping shield for lithium-sulfur batteries. •MoS 2 /graphene interlayer shows strong chemical interactions with LiPSs. •MoS 2 /graphene interlayer forms a 3D network to facilitate electron and ion transfer during the discharge-charge processes. •The resultant lithium-sulfur batteries exhibit a superior rate capacity and improved cycling capacity. -- Abstract: A dual functional interlayer consisted of composited two-dimensional MoS 2 and graphene has been developed as an efficient polysulfide barrier for lithium-sulfur batteries (LSBs). With such a configuration, LSBs show a superior rate capacity and improved cycling capacity. The excellent electrochemical performance can be attributed to the strong bonding interactions between the MoS 2 /graphene interlayer and the formed lithium polysulfides (LiPSs) as well as the good electrical conductivity of the MoS 2 /graphene composite. The MoS 2 /graphene interlayer can physically block LiPSs by the graphene nanosheets and chemically suppress the dissolution of LiPSs by the polar MoS 2 nanoflowers. Such a dual functional interlayer further provides a good contact with the surface of the sulfur cathode, acts as an upper current collector and greatly improves the sulfur utilization and the rate capability of LSBs.

  16. Mo(ve)ment-methodology

    DEFF Research Database (Denmark)

    Mørck, Line Lerche; Christian Celosse-Andersen, Martin

    2018-01-01

    This paper describes the theoretical basis for and development of a moment-movement research methodology, based on an integration of critical psychological practice research and critical ethnographic social practice theory. Central theoretical conceptualizations, such as human agency, life...... conditions and identity formation, are discussed in relation to criminological theories of gang desistance. The paper illustrates how the mo(ve)ment methodology was applied in a study of comprehensive processes of identity (re)formation and gang exit processes. This study was conducted with Martin, a former....... This is a moment which captures Martin’s complex and ambiguous feelings of conflictual concerns, frustration, anger, and a new feeling of insecurity in his masculinity, as well as engagement and a sense of deep meaningfulness as he becomes a more reflective academic. All these conflicting feelings also give...

  17. Development of fission Mo-99 production technology

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-05-01

    Fission Mo-99 is the only parent nuclide of Tc-99m, an extremely useful tool for mdeical diagnosis, with an estimated usage of greater than 80% of nuclear medicine applicatons. HEU and LEU targets to optimize in HANARO irradiation condition suggested and designed for domestic production of fission Mo-99. The optimum process conditions are established in each unit process to meet quality requirements of fission Mo-99 products, and the results of performance test in combined process show Mo separation and purification yield of the above 97%. The concept of Tc generator production process is established, and the result of performance test show Tc production yield of 98.4% in Tc generator procuction process. The drafts is prepared for cooperation of technical cooperation and business investment with foreign country. Evaluation on economic feasibility is accompanied for fission Mo-99 and Tc-99m generator production.

  18. Development of fission Mo-99 production technology

    International Nuclear Information System (INIS)

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

    2000-05-01

    Fission Mo-99 is the only parent nuclide of Tc-99m, an extremely useful tool for mdeical diagnosis, with an estimated usage of greater than 80% of nuclear medicine applicatons. HEU and LEU targets to optimize in HANARO irradiation condition suggested and designed for domestic production of fission Mo-99. The optimum process conditions are established in each unit process to meet quality requirements of fission Mo-99 products, and the results of performance test in combined process show Mo separation and purification yield of the above 97%. The concept of Tc generator production process is established, and the result of performance test show Tc production yield of 98.4% in Tc generator procuction process. The drafts is prepared for cooperation of technical cooperation and business investment with foreign country. Evaluation on economic feasibility is accompanied for fission Mo-99 and Tc-99m generator production

  19. Solution chemistry of Mo(III) and Mo(IV): Thermodynamic foundation for modeling localized corrosion

    International Nuclear Information System (INIS)

    Wang Peiming; Wilson, Leslie L.; Wesolowski, David J.; Rosenqvist, Joergen; Anderko, Andrzej

    2010-01-01

    To investigate the behavior of molybdenum dissolution products in systems that approximate localized corrosion environments, solubility of Mo(III) in equilibrium with solid MoO 2 has been determined at 80 deg. C as a function of solution acidity, chloride concentration and partial pressure of hydrogen. The measurements indicate a strong increase in solubility with acidity and chloride concentration and a weak effect of hydrogen partial pressure. The obtained results have been combined with literature data for systems containing Mo(III), Mo(IV), and Mo(VI) in solutions to develop a comprehensive thermodynamic model of aqueous molybdenum chemistry. The model is based on a previously developed framework for simulating the properties of electrolyte systems ranging from infinite dilution to solid saturation or fused salt limit. To reproduce the measurements, the model assumes the presence of a chloride complex of Mo(III) (i.e., MoCl 2+ ) and hydrolyzed species (MoOH 2+ , Mo(OH) 2 + , and Mo(OH) 3 0 ) in addition to the Mo 3+ ion. The model generally reproduces the experimental data within experimental scattering and provides a tool for predicting the phase behavior and speciation in complex, concentrated aqueous solutions. Thus, it provides a foundation for simulating the behavior of molybdenum species in localized corrosion environments.

  20. Spent 99Mo/99mTc generator as an economical source of 99Mo

    International Nuclear Information System (INIS)

    El-Kolaly, M.T.

    1990-01-01

    An improved method for utilization and purification of 99 Mo from spent 90 Mo/ 99m Tc generators has been described. After washing the generator with saline to remove the generated 99m Tc, followed by 2 mL 5 M NaOH containing a few drops of H 2 O 2 , the 99 Mo was quantitatively eluted from the generator with 5 mL 5 M NaOH. The alkaline eluate containing 99 Mo was contaminated with partially dissolved alumina. In the present method, an anion-exchange resin Dowex 1 x 8 column was used for purification of 99 Mo from the contaminating alumina. The resultant 99 Mo was of high purity and contained 3+ /mL 99 Mo solution, as estimated by atomic absorption. (author)

  1. 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.

  2. Influence of Mo on the structure of borosilicate glass for the immobilization of high level waste

    International Nuclear Information System (INIS)

    Petrov, I.; Dimitriev, Y.; Kashchieva, E.

    2015-01-01

    It has been shown that the classic multi-borosilicate glass with concentration of MoO 3 has a low melting in the range of 1300 to 1400 ° C, but for achieving of complete homogenization and vitrification it is required temperature above 1400 ° C. Under this temperature in all tested samples areas of crystallization were observed, due to incomplete vitrification processes. It is understood that in all multicomponent borosilicate glass featuring MoO 3 , occur micro vitrification processes, and at a concentration of MoO 3 above 20% - macro segregation; It has been shown that the introduction of Nd in compound borosilicate glass featuring MoO 3 is observed crystallization of the phase Na 0.5 Nd 0.5 Mo, and it has been also found that the phase Na 0.5 Nd 0.5 Mo 4 can be synthesized either by solid phase reaction or supercooled melt. The results of surveys show that It is possible to prevent the occurrence of liquid phase separation in the studied multicomponent glass. From a structural point of view, the cause of liquid phase separation is the result of structural incompatibility of molybdenum units with structural units borosilicate network since not been established links Mo-O-B-O and Mo-Si. From a thermodynamic point of view in the lamination multi windows may be due to overlapping areas of delamination in component binary and triple systems. From the kinetic point of view of course the liquid phase by settling, and crystallization may be due to imbalances conditions the cooling process, in the course of which flow various processes of imbalances metastable settling, followed by crystallization of molybdate phases

  3. Phase formation in Na2MoO4 - MgMoO4 - Cr2(MoO4)3 system

    International Nuclear Information System (INIS)

    Kotova, I.Yu.; Kozhevnikova, N.M.

    1998-01-01

    Interaction within Na 2 MoO 4 - MgMoO 4 - Cr 2 (MoO 4 ) 3 ternary system is studied by X ray phase and DTA methods. State diagram of NaCr(MoO 4 ) 2 - MgMoO 4 section is plotted. Production of ternary molybdates of Na 1-x Mg 1-x Cr 1+x (MoO 4 ) 3 , where 0 ≤ x ≤ 0.3, and NaMg 3 Cr(MoO 4 ) 5 composition is ascertained [ru

  4. 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

  5. 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.

  6. Development of fission Mo-99 production technology

    International Nuclear Information System (INIS)

    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

  7. Mass spectrometric determination of stability of gaseous BaMoO2, Ba2MoO4, Ba2MoO5, Ba2Mo2O8 molecules

    International Nuclear Information System (INIS)

    Kudin, L.S.; Balduchchi, Dzh.; Dzhil'i, G.; Gvido, M.

    1982-01-01

    During the mass spectrometric investigation of BaCrO 4 evaporation Cr + , Ba + , BaO + main ions are recorded as well as BaMoO 4 + , BaMoO 3 + , BaMoO 2 + , BaMoO + , BaMoO 4 + , Ba 2 MoO 5 + , BaMo 2 O 8 + ions - the products of ionization of three-component (Ba, Mo, M) molecules, forming as a result of substance chemical interaction with the material of an effusion cell (Mo). Heats of formation of BaMoO 2 , Ba 2 MoO 4 , Ba 2 MoO 5 and Ba 2 Mo 2 O 8 molecules which constituted - 577+-70, -1343+-115, -1464+-70, -2393+-90 k J/mol respectively are determined on the base of the analysis of curves of ionisation efficiency and of reaction heats Ba 2 MoO 5 =BaO+BaMoO 4 , ΔH 0 0 =322+-60 kJ/mol Ba 2 Mo 2 O 8 =2BaMoO 4 , ΔH 0 0 =351+-80 kJ/mol calculated with the use of third low of thermodynamics [ru

  8. 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.

  9. Extended analysis of Mo VI

    International Nuclear Information System (INIS)

    Edlen, B.; Rahimullah, K.; Tauheed, A.; Chaghtai, M.S.Z.

    1985-01-01

    The analysis of the RbI-like spectrum Mo VI has been extended to include a total of some 110 classified lines and 44 energy levels belonging to the one-electron configurations 4s 2 4p 6 ( 1 S)nl with n ranging up to 9 and l up to 7. The analysis is based on recordings of vacuum spark spectra made at Lund in the region 230-2350 A, complemented by a list of lines from 2193 to 6336 A observed and identified by Romanov and Striganov in a Penning type arc discharge. The one-electron level system is partly mixed with core-excited configurations, not treated in the present paper. Especially the nf series is strongly perturbed by 4s 2 4p 5 4d 2 , and an anomalous behaviour of the ng series is explained by interaction with the 2 G term of 4s4p 6 4d 2 . The ionization limit, derived from 6h, 7i and 8k by means of the polarization formula, is found to be 555 132+-2 cm -1 . (orig.)

  10. Nanoparticles of superconducting γ-Mo2N and δ-MoN

    International Nuclear Information System (INIS)

    Gomathi, A.; Sundaresan, A.; Rao, C.N.R.

    2007-01-01

    We have been able to prepare nanoparticles (∼4 nm diameter) of cubic γ-Mo 2 N by a simple procedure involving the reaction of MoCl 5 with urea at 873 K. The nanoparticles show a superconducting transition around 6.5 K. The γ-Mo 2 N nanoparticles are readily transformed to nanoparticles of δ-MoN with a slightly larger diameter on heating in a NH 3 atmosphere at 573 K. Phase-pure δ-MoN obtained by this means shows a superconducting transition around 5 K. - Graphical abstract: TEM image of the γ-Mo 2 N particles with the inset showing the resistivity of the sample as a function of temperature

  11. Stacking change in MoS2 bilayers induced by interstitial Mo impurities.

    Science.gov (United States)

    Cortés, Natalia; Rosales, Luis; Orellana, Pedro A; Ayuela, Andrés; González, Jhon W

    2018-02-01

    We use a theoretical approach to reveal the electronic and structural properties of molybdenum impurities between MoS 2 bilayers. We find that interstitial Mo impurities are able to reverse the well-known stability order of the pristine bilayer, because the most stable form of stacking changes from AA' (undoped) into AB' (doped). The occurrence of Mo impurities in different positions shows their split electronic levels in the energy gap, following octahedral and tetrahedral crystal fields. The energy stability is related to the accommodation of Mo impurities compacted in hollow sites between layers. Other less stable configurations for Mo dopants have larger interlayer distances and band gaps than those for the most stable stacking. Our findings suggest possible applications such as exciton trapping in layers around impurities, and the control of bilayer stacking by Mo impurities in the growth process.

  12. 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...

  13. Alternative energy resources for MoDOT

    Science.gov (United States)

    2011-02-01

    This research investigates environmentally friendly alternative energy sources that could be used by MoDOT in various areas, and develops applicable and sustainable strategies to implement those energy sources.

  14. 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.

  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. 99Mo production using MoO3 pellets obtained by mechanical compression and heat treatment

    International Nuclear Information System (INIS)

    Rojas, Jorge; Mendoza, Pablo; Lopez, Alcides

    2014-01-01

    This paper shows the results of the MoO 3 pellets fabrication by mechanical compression and the heat treatment method (MCHT) in order to optimize the production of 99 Mo in the RACSO Nuclear Center. The effects of polyvinyl alcohol (PVA) as binder are assessed by heat treatment of pellets in air atmosphere, evaluating the elimination process with increasing temperature and solubility in 5N NaOH. The results show that the pellets fabrication technique is suitable because fulfills the required technical specifications, allows to irradiate 50 % more of 98 Mo mass and facilitate a safer radiological handling of the irradiated MoO 3 . (authors).

  17. Biodistribution of 99Mo in rats

    International Nuclear Information System (INIS)

    Souza, Raphael Sancho Sisley de; Ribeiro, Bianca da Silva; Dantas, Ana Leticia Almeida; Dantas, Bernardo Maranhao; Bernardo Filho, Mario

    2009-01-01

    The modification of 99 Mo standard metabolism in the presence of MDP would alter the dosimetry of this radionuclide in nuclear medicine patients. Therefore, the objective of this work is to evaluate the influence of MDP in the biodistribution of 99 Mo. Wistar rats were divided in two groups of six animals, being inoculated respectively 99 Molibdate and 99 Mo+MDP via plex ocular. The biodistribution study was carried out after 10 and 120 minutes respectively. The organs were counted with a NaI(Tl) detector. The uptake values did not present significant differences among the groups. An in vitro study through planar chromatography was carried out to determine the affinity between molybdenum and MDP. The results show that 99 Mo has low affinity both to propanone and NaCl-0.9% solution. However, 99 Mo in the presence of MDP presented affinity to NaCl-0.9% solution and low affinity to propanone suggesting that 99 Mo was bound to MDP under the conditions of the experiment. (author)

  18. Coupling Mo2C@C core-shell nanocrystals on 3D graphene hybrid aerogel for high-performance lithium ion battery

    Science.gov (United States)

    Xin, Hailin; Hai, Yang; Li, Dongzhi; Qiu, Zhaozheng; Lin, Yemao; Yang, Bo; Fan, Haosen; Zhu, Caizhen

    2018-05-01

    Hybrid aerogel by dispersing Mo2C@C core-shell nanocrystals into three-dimensional (3D) graphene (Mo2C@C-GA) has been successfully prepared through two-step methods. Firstly, carbon-coated MoO2 nanocrystals uniformly anchor on 3D graphene aerogel (MoO2@C-GA) via hydrothermal reaction. Then the MoO2@C-GA precursor is transformed into Mo2C@C-GA after the following carbonization process. Furthermore, the freeze-drying step plays an important role in the resulting pore size distribution of the porous networks. Moreover, graphene aerogels exhibit extremely low densities and superior electrical properties. When evaluated as anode material for lithium ion battery, Mo2C@C-GA delivers excellent rate capability and stable cycle performance when compared with C-GA and Mo2C nanoparticles. Mo2C@C-GA exhibits the initial discharge capacity of 1461.4 mA h g-1 at the current density of 0.1 A g-1, and retains a reversible capacity of 1089.8 mA h g-1 after 100 cycles at a current density of 0.1 A g-1. Even at high current density of 5 A g-1, a discharge capacity of 623.5 mA h g-1 can be still achieved. The excellent performance of Mo2C@C-GA could be attributed to the synergistic effect of Mo2C@C nanocrystals and the 3D graphene conductive network.

  19. Microstructural defects modeling in the Al-Mo system

    International Nuclear Information System (INIS)

    Pascuet, Maria I.; Fernandez, Julian R.; Monti, Ana M.

    2006-01-01

    In this work we have utilized computer simulation techniques to study microstructural defects, such as point defects and interfaces, in the Al-Mo alloy. Such alloy is taken as a model to study the Al(fcc)/U-Mo(bcc) interface. The EAM interatomic potential used has been fitted to the formation energy and lattice constant of the AlMo 3 intermetallic. Formation of vacancies for both components Al and Mo and anti-sites, Al Mo and Mo Al , as well as vacancy migration was studied in this structure. We found that the lowest energy defect complex that preserves stoichiometry is the antisite pair Al Mo +Mo Al , in correspondence with other intermetallics of the same structure. Our results also suggest that the structure of the Al(fcc)/Mo(bcc) interface is unstable, while that of the Al(fcc)/Al 5 Mo interface is stable, as observed experimentally. (author) [es

  20. 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.

  1. Microstructure and tribological properties of NiMo/Mo2Ni3Si intermetallic 'in-situ' composites

    International Nuclear Information System (INIS)

    Gui Yongliang; Song Chunyan; Yang Li; Qin Xiaoling

    2011-01-01

    Research highlights: → Wear resistant NiMo/Mo 2 Ni 3 Si intermetallic 'in-situ' composites was fabricated successfully with Mo-Ni-Si powder blends as the starting materials. Microstructure of the NiMo/Mo 2 Ni 3 Si composites consists of Mo 2 Ni 3 Si primary dendrites, binary intermetallic phase NiMo and small amount of Ni/NiMo eutectics structure. The NiMo/Mo 2 Ni 3 Si composites exhibited high hardness and outstanding tribological properties under room-temperature dry-sliding wear test conditions which were attributed to the covalent-dominant strong atomic bonds and excellent combination of strength and ductility and toughness. - Abstract: Wear resistant NiMo/Mo 2 Ni 3 Si intermetallic 'in-situ' composites with a microstructure of ternary metal silicide Mo 2 Ni 3 Si primary dendritic, the long strip-like NiMo intermetallic phase, and a small amount of Ni/NiMo eutectics structure were designed and fabricated using molybdenum, nickel and silicon elemental powders. Friction and wear properties of NiMo/Mo 2 Ni 3 Si composites were evaluated under different contact load at room-temperature dry-sliding wear test conditions. Microstructure, worn surface morphologies and subsurface microstructure were characterized by OM, XRD, SEM and EDS. Results indicate that NiMo/Mo 2 Ni 3 Si composites have low fiction coefficient, excellent wear resistance and sluggish wear-load dependence. The dominant wear mechanisms of NiMo/Mo 2 Ni 3 Si composites are soft abrasion and slightly superficial oxidative wear.

  2. 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.

  3. Immobilization of Mo(IV) complex in hybrid matrix obtained via sol-gel technique

    Energy Technology Data Exchange (ETDEWEB)

    Marques, C.; Sousa, A.M.; Freire, C.; Neves, I.C.; Fonseca, A.M.; Silva, C.J.R

    2003-10-06

    A molybdenum(IV) complex, trans-bis-[1,2-bis(diphenylphosphino)ethane]-fluoro-(diazopropano) -molybdenum tetraphenylborate, [MoF(DIAZO)(dppe){sub 2}][BPh{sub 4}], was prepared and immobilized in a hybrid matrix synthesized by the sol-gel process. The host matrix, designated as U(500), is an organic-inorganic network material, classed as ureasil, that combines a reticulated siliceous backbone linked by short polyether-based segments. Urea bridges make the link between these two components, and the polymerization of silicate substituted terminal groups generates the inorganic network. The free Mo(IV) complex and all new materials were characterized by spectroscopic techniques (FT-IR and UV-Vis) and thermal analysis (DSC). The ionic conductivity of the resulting material was also studied. The results indicate that immobilized Mo(IV) complex has kept its solid-state structure, although there is evidence of inter-molecular interactions between the Mo(IV) complex and some groups/atoms of the hybrid host matrix.

  4. 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.

  5. Spectrophotometric and potentiometric studies of oxidation of Mo(III) by Mo(VI) in phosphoric acid medium

    International Nuclear Information System (INIS)

    Kumar, Arvind; Verma, G.S.P.

    1975-01-01

    Oxidation of Mo(III) (green) by Mo(VI) in an inert atmosphere and in orthophosphoric acid medium at various acid concentrations is reported. Potentiometric and spectrophotometric data suggest that oxidation of Mo(III) proceeds to Mo(V) through a binuclear species Mo(III) Mo(IV) absorbing at 400 nm. The formation of this species is facilitated at high acid concentrations. It is further found that quantitative conversion of Mo(III) into Mo(V) takes place at fairly high acid concentrations. In high phosphoric acid concentrations, solution of Mo(III) has been found to be oxidized to Mo(VI) by air and hence this can be used as a good oxygen absorber. (author)

  6. Spectrophotometric and potentiometric studies of oxidation of Mo(III) by Mo(VI) in phosphoric acid medium

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A; Verma, G S.P. [Ranchi Coll. (India). Dept. of Chemistry

    1975-12-01

    Oxidation of Mo(III) (green) by Mo(VI) in an inert atmosphere and in orthophosphoric acid medium at various acid concentrations is reported. Potentiometric and spectrophotometric data suggest that oxidation of Mo(III) proceeds to Mo(V) through a binuclear species Mo(III) Mo(IV) absorbing at 400 nm. The formation of this species is facilitated at high acid concentrations. It is further found that quantitative conversion of Mo(III) into Mo(V) takes place at fairly high acid concentrations. In high phosphoric acid concentrations, solution of Mo(III) has been found to be oxidized to Mo(VI) by air and hence this can be used as a good oxygen absorber.

  7. Measurement of Mo-99 column activity in the evaluation of Mo-99/Tc-99m generator

    International Nuclear Information System (INIS)

    Kuster, Z.

    1994-01-01

    In order to calculate the real elution efficiency of Mo-99/Tc-99m generator the Mo-99 content on the column has to be previously determined. As found in this work, the external measurement of Mo-99-column activity by means of Geiger-Mueller counter is a simple, fast and reliable method. Generally, Mo-99-column is placed slightly out of the center of the generator; therefore the externally measured flux of photons (φ) is an angular-dependent function. If the thickness of the lead container is radially uniform, the flux measured at some distance from the generator (which is rotated in 2π/3 steps) is given by the equation φ = A (1 + Bcos (α-2π(i - 2)/3)) -1 , i=1,2 or 3 (Eq.1) where A is a numerical constant depending on the Mo-99-column activity, B is a numerical constant depending on the Mo-99- column position within the lead container, the angle α depends on the initial orientation of the generator. A total of 20 generator were studied. The measured Mo-99-column activities (Capintec dose calibrator) were in the range 13.1- 35.11 GBq. Contrary to the findings of Vinberg and Kristensen (Eur J Nucl Med 1/1976(219), values of A (Eq. 1) are in good correlation (r 2 =0.9794) with the measured Mo-99-column activities. (author)

  8. EXAFS study of Mo2N and Mo nitrides supported on zeolites

    International Nuclear Information System (INIS)

    Liu Zhenlin; Meng Ming; Fu Yilu; Jiang Ming; Hu Tiandou; Xie Yaning; Liu Tao

    2002-01-01

    In the present study, the reaction is applied to prepare molybdenum nitrides with high surface area, and zeolites are used as supports. The EXAFS of the Mo K-absorption edge is measured and the change of coordination environment of Mo atoms before and after the nitridation is revealed

  9. DFT study of the reactions of Mo and Mo with CO2 in gas phase

    Indian Academy of Sciences (India)

    understanding the mechanism of second-row metal reacting with CO2. The minimum energy ... et al.18 performed an IR study on the reaction of laser- ablated Mo atom .... indicate that the weak electrostatic interaction between. Mo. + and CO2 ...

  10. Cu4Pr6(MoO4)11-Pr2(MoO4)3 system

    International Nuclear Information System (INIS)

    Arzumanyan, G.A.

    1982-01-01

    Existence boundaries and Dalton compositions (CuPr(MoO 4 ) 2 , CuPr 3 (MoO 4 ) 5 ) of solid solutions that in the mojority are of shcheelite dsitored structure have been determined in the Cu 4 Pr 6 (MoO 4 ) 11 -Pr 2 (MoO 4 ) 3 system. It has been revealed that regions of homogeneity near the CuPr(MoO 4 ) 2 composition have a horseshoeshaped profile

  11. 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

    Edhaim, Fatimah A.; Rothenberger, Alexander

    2017-01-01

    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

  12. ITO-free flexible organic photovoltaics with multilayer MoO3/LiF/MoO3/Ag/MoO3 as the transparent electrode

    International Nuclear Information System (INIS)

    Chen, Shilin; Dai, Yunjie; Zhang, Hongmei; Zhao, Dewei

    2016-01-01

    We present efficient flexible organic photovoltaics (OPVs) with multiple layers of molybdenum oxide (MoO 3 )/LiF/MoO 3 /Ag/MoO 3 as the transparent electrode, where the thin Ag layer yields high conductivity and the dielectric layer MoO 3 /LiF/MoO 3 has high transparency due to optical interference, leading to improved power conversion efficiency compared with indium tin oxide (ITO) based devices. The MoO 3 contacting organic active layer is used as a buffer layer for good hole extraction. Thus, the multilayer MoO 3 /LiF/MoO 3 /Ag/MoO 3 can improve light transmittance and also facilitate charge carrier extraction. Such an electrode shows excellent mechanical bendability with a 9% reduction of efficiency after 1000 cycles of bending due to the ductile nature of the thin metal layer and dielectric layer used. Our results suggest that the MoO 3 /LiF/MoO 3 /Ag/MoO 3 multilayer electrode is a promising alternative to ITO as an electrode in OPVs. (paper)

  13. Room temperature isotherms for Mo and Ni

    International Nuclear Information System (INIS)

    Masse, J.L.

    1986-11-01

    Isotherms at room temperature for Mo and Ni are proposed. They are of three types: BIRCH, KEANE and BORN-MIE. The adjustable constants appearing in these isotherms have been determined from experimental quantities at zero pressure. An evaluation of the limit of (δB T /δP) T as P #-> # ∞, where B T is the isothermal bulk modulus, has been also used. These three isotherms obtained for Mo and Ni are compared with isotherms derived from shock-wave data according to the PRIETO's model. There is a good agreement between these and these derived from shock-wave data. The three isotherms proposed for Mo and Ni can be considered as valid until pressures of several B To , where B To is the bulk modulus B T at P = o [fr

  14. Wetting of metals and glasses on Mo

    Energy Technology Data Exchange (ETDEWEB)

    Saiz, Eduardo; Tomsia, Antoni P.; Saiz, Eduardo; Lopez-Esteban, Sonia; Benhassine, Mehdi; de Coninck, Joel; Rauch, Nicole; Ruehle, Manfred

    2008-01-08

    The wetting of low melting point metals and Si-Ca-Al-Ti-O glasses on molybdenum has been investigated. The selected metals (Au, Cu, Ag) form a simple eutectic with Mo. Metal spreading occurs under nonreactive conditions without interdiffusion or ridge formation. The metals exhibit low (non-zero) contact angles on Mo but this requires temperatures higher than 1100 C in reducing atmospheres in order to eliminate a layer of adsorbed impurities on the molybdenum surface. By controlling the oxygen activity in the furnace, glass spreading can take place under reactive or nonreactive conditions. We have found that in the glass/Mo system the contact angle does not decrease under reactive conditions. In all cases, adsorption from the liquid seems to accelerate the diffusivity on the free molybdenum surface.

  15. 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’.

  16. 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.

  17. MoGIRE: A Model for Integrated Water Management

    Science.gov (United States)

    Reynaud, A.; Leenhardt, D.

    2008-12-01

    Climate change and growing water needs have resulted in many parts of the world in water scarcity problems that must by managed by public authorities. Hence, policy-makers are more and more often asked to define and to implement water allocation rules between competitive users. This requires to develop new tools aiming at designing those rules for various scenarios of context (climatic, agronomic, economic). If models have been developed for each type of water use however, very few integrated frameworks link these different uses, while such an integrated approach is a relevant stake for designing regional water and land policies. The lack of such integrated models can be explained by the difficulty of integrating models developed by very different disciplines and by the problem of scale change (collecting data on large area, arbitrate between the computational tractability of models and their level of aggregation). However, modelers are more and more asked to deal with large basin scales while analyzing some policy impacts at very high detailed levels. These contradicting objectives require to develop new modeling tools. The CALVIN economically-driven optimization model developed for managing water in California is a good example of this type of framework, Draper et al. (2003). Recent reviews of the literature on integrated water management at the basin level include Letcher et al. (2007) or Cai (2008). We present here an original framework for integrated water management at the river basin scale called MoGIRE ("Modèle pour la Gestion Intégrée de la Ressource en Eau"). It is intended to optimize water use at the river basin level and to evaluate scenarios (agronomic, climatic or economic) for a better planning of agricultural and non-agricultural water use. MoGIRE includes a nodal representation of the water network. Agricultural, urban and environmental water uses are also represented using mathematical programming and econometric approaches. The model then

  18. The modulation of Schottky barriers of metal-MoS2 contacts via BN-MoS2 heterostructures.

    Science.gov (United States)

    Su, Jie; Feng, Liping; Zhang, Yan; Liu, Zhengtang

    2016-06-22

    Using first-principles calculations within density functional theory, we systematically studied the effect of BN-MoS2 heterostructure on the Schottky barriers of metal-MoS2 contacts. Two types of FETs are designed according to the area of the BN-MoS2 heterostructure. Results show that the vertical and lateral Schottky barriers in all the studied contacts, irrespective of the work function of the metal, are significantly reduced or even vanish when the BN-MoS2 heterostructure substitutes the monolayer MoS2. Only the n-type lateral Schottky barrier of Au/BN-MoS2 contact relates to the area of the BN-MoS2 heterostructure. Notably, the Pt-MoS2 contact with n-type character is transformed into a p-type contact upon substituting the monolayer MoS2 by a BN-MoS2 heterostructure. These changes of the contact natures are ascribed to the variation of Fermi level pinning, work function and charge distribution. Analysis demonstrates that the Fermi level pinning effects are significantly weakened for metal/BN-MoS2 contacts because no gap states dominated by MoS2 are formed, in contrast to those of metal-MoS2 contacts. Although additional BN layers reduce the interlayer interaction and the work function of the metal, the Schottky barriers of metal/BN-MoS2 contacts still do not obey the Schottky-Mott rule. Moreover, different from metal-MoS2 contacts, the charges transfer from electrodes to the monolayer MoS2, resulting in an increment of the work function of these metals in metal/BN-MoS2 contacts. These findings may prove to be instrumental in the future design of new MoS2-based FETs with ohmic contact or p-type character.

  19. Phase relations in the M2MoO4 - Ag2MoO4 - Hf(MoO4)2 (M=Li, Na) systems

    International Nuclear Information System (INIS)

    Bazarova, Zh.G.; Bazarov, B.G.; Balsanova, L.V.

    2002-01-01

    The M 2 MoO 4 - Ag 2 MoO 4 - Hf(MoO 4 ) 2 (M=Li, Na) systems were studied by X-ray diffraction and differential thermal analyses in the subsolidus area (450 - 500 Deg C) for the first time. The formation of the binary compound with the variable composition Li 4-x Hf 1+0.2x (MoO 4 ) 4 (0 ≤ x ≤ 0.6) in the Li 2 MoO 4 - Hf(MoO 4 ) 2 system and the ternary molybdates Li 4 Ag 2 Hf(MoO 4 ) 5 (S 1 ) and Na 2 Ag 2 Hf(MoO 4 ) 4 (S 2 ) was established and the thermal characteristics of the prepared compounds were examined. The new binary molybdate Ag 2 Hf(MoO 4 ) 3 was prepared by the reaction between Ag 2 MoO 4 and Hf(MoO 4 ) 2 [ru

  20. Investigation of BaMoO4-Ln2(MoO4)3 systems (Ln = Nd, Sm, Yb)

    International Nuclear Information System (INIS)

    Vakulyuk, V.V.; Evdokimov, A.A.; Khomchenko, G.P.

    1982-01-01

    Using the methods of X-ray phase and differential-thermal analyses phase ratios in the systems BaMoO 4 -Ln 2 (MoO 4 ) 3 (Ln=Nd, Sm, Yb); BaNd 2 (MoO 4 ) 4 -MaGd 2 (MoO 4 ) are studied. Unit cell parameters and the character of melting of the compounds BaLn 2 (MoO 4 ) 4 are specified. Effect of growth conditions on laminated nature of BaGd 2 (MoO 4 ) 4 monocrystals is studied

  1. Synthesis of rambutan-like MoS2/mesoporous carbon spheres nanocomposites with excellent performance for supercapacitors

    Science.gov (United States)

    Zhang, Shouchuan; Hu, Ruirui; Dai, Peng; Yu, Xinxin; Ding, Zongling; Wu, Mingzai; Li, Guang; Ma, Yongqing; Tu, Chuanjun

    2017-02-01

    A novel rambutan-like composite of MoS2/mesoporous carbon spheres were synthesized by a simple two-step hydrothermal and post-annealing approach via using glucose as C source and Na2MoO4·2H2O and thiourea as Mo and S sources. It is found that the morphology and electrochemical properties can be effectively controlled by the change of the weight ratio of coated MoS2 sheets to carbon spheres. When used as electrode material for supercapacitor, the hybrid MoS2/carbon spheres show a high specific capacity of 411 F/g at a current density of 1 A/g and 272 F/g at a high discharge current density of 10 A/g. The annealing treatment at 700 °C transformed the core carbon spheres into mesoporous ones, which served as the conduction network and favor the enhancement of the specific capacitance. In addition, the strain released during the charge/discharge process can be accommodated and the structural integrity can be kept, improving the cycling life. After 1000 cycles, the capacitance retention of the hybrid MoS2/carbon spheres is 93.2%.

  2. Effect of Ni on the characteristics and hydrogenation activity of sulfide Mo/γ-Al2O3

    International Nuclear Information System (INIS)

    Schachtl, E.; Wuttke, E.; Gutierrez, O.Y.; Lercher, J.A.

    2012-01-01

    The hydrogenation of phenanthrene was explored on sulfide Mo/γ-Al 2 O 3 catalysts promoted with increasing concentrations of Ni. The characterization of the materials was done by N 2 -physisorption, X-ray diffraction, transmission electron microscopy, temperature programmed sulfidation and NO adsorption experiments. Increasing loading of Ni improves the dispersion of MoS 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 2 leading to shorter slabs with higher stacking degree than on Mo/γ-Al 2 O 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.)

  3. 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...

  4. Ventilation system for 99Mo production apparatus

    International Nuclear Information System (INIS)

    Izumo, Mishiroku; Okane, Shougo; Sorita, Takami; Aoyama, Saburou

    1978-04-01

    In production of 20 Ci 99 Mo from 235 U fission, about 120 Ci of radioiodine ( 131 I, 132 I, and 133 I) is involved. To remove airborne radioiodine from the exhaust air from production apparatus and minimize radioiodine release to the atmosphere, the ventilation system is equipped with 2 units of Model-FD charcoal filter (KI 3 -Impregnated charcoal 2 inch thick of Barnebey-Cheney Co.). From September 1976 to December 1977, 21 runs of 99 Mo production involving airborne radioiodine were carried out. The ventilation system was operated continuously for the whole 15 months period; variation in removal efficiency of airborne radioiodine from the exhaust air stream was observed. In the runs valuable experiences were gained in operation and maintenance of the ventilation system including activated charcoal filter and health-physics management of such facility. Following are the results: (1) Airborne radioiodine from 99 Mo production apparatus is reduced to 10 -3 % of the original quantity. (2) When the ventilation system is operated at a maximum air flow rate through the filter, the average efficiency during 15 months is over 98%. (3) Airborne radioiodine released from 99 Mo production apparatus to the ventilation system is less than 5% particulate iodine and alkyl iodines and more than 95% inorganic iodine. (4) Airborne radioiodine released from the stack is less than 28 μCi/run, which is below the limit in regulations on Radioisotope Production Laboratory. (auth.)

  5. 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...

  6. Fixation Of Mo In Uranium Leach Liquor By Activated Carbon

    International Nuclear Information System (INIS)

    Mainar, S.; Guswita, A.; Erni, R.A.; Susilaningtyas

    1996-01-01

    The use of activated carbon for Mo fixation by bulk system is reported. Several factors influencing the fixation process were examined, including contact time, carbon particle size, carbon porosity and the effect of other elements present in Mo containing solutions. Experimental data showed that an adsorption equilibrium of Mo on of activated carbon and 0,85 to 1,18 mm of carbon particle size under forced-convection mass transfer in 100 ml solution that contains + 0,56 m mol of Mo and +. 0,25 m mol Of U was reached after 6 hours period. Under those conditions, about 0,50 m mol of Mo and 0,026 m mol of U were adsorbed into carbon. High concentration of rare earth elements decreased Mo adsorption, hence, the use of activated carbon was not effective to separate Mo from the digestion liquor of Rirang are where Mo was adsorbed, into the carbon + 34,5 %

  7. X-ray fluorescence analysis of Fe - Ni - Mo systems

    International Nuclear Information System (INIS)

    Belyaev, E.E.; Ershov, A.V.; Mashin, A.I.; Mashin, N.I.; Rudnevskij, N.K.

    1998-01-01

    Procedures for the X-ray fluorescence determination of the composition and thickness of Fe - Ni - Mo thin films and the concentration of elements in thick films of the Fe - Ni - Mo alloy are developed [ru

  8. Interdiffusion between U(Mo,Pt) or U(Mo,Zr) and Al or Al A356 alloy

    International Nuclear Information System (INIS)

    Komar Varela, C.; Mirandou, M.; Arico, S.; Balart, S.; Gribaudo, L.

    2009-01-01

    Solid state reactions in chemical diffusion couples U-7 wt.%Mo-0.9 wt.%Pt/Al at 580 deg. C and U-7 wt.%Mo-0.9 wt.%Pt/Al A356 alloy, U-7 wt.%Mo-1 wt.%Zr/Al and U-7 wt.%Mo-1 wt.%Zr/Al A356 alloy at 550 deg. C were characterized. Results were obtained from optical and scanning electron microscopy, electron probe microanalysis and X-ray diffraction. The UAl 3, UAl 4 and Al 20 Mo 2 U phases were identified in the interaction layers of γU(Mo,Pt)/Al and γU(Mo,Zr)/Al diffusion couples. Al 43 Mo 4 U 6 ternary compound was also identified in γU(Mo,Zr)/Al due to the decomposition of γU(Mo,Zr) phase. The U(Al,Si) 3 and U 3 Si 5 phases were identified in the interaction layers of γU(Mo,Pt)/Al A356 and γU(Mo,Zr)/Al A356 diffusion couples. These phases are formed due to the migration of Si to the interaction layer. In the diffusion couple U(Mo,Zr)/Al A356, Zr 5 Al 3 phase was also identified in the interaction layer. The use of synchrotron radiation at Brazilian Synchrotron Light Laboratory (LNLS, CNPq, Campinas, Brazil) was necessary to achieve a complete crystallographic characterization.

  9. Transfer matrix approach to electron transport in monolayer MoS2/MoO x heterostructures

    Science.gov (United States)

    Li, Gen

    2018-05-01

    Oxygen plasma treatment can introduce oxidation into monolayer MoS2 to transfer MoS2 into MoO x , causing the formation of MoS2/MoO x heterostructures. We find the MoS2/MoO x heterostructures have the similar geometry compared with GaAs/Ga1‑x Al x As semiconductor superlattice. Thus, We employ the established transfer matrix method to analyse the electron transport in the MoS2/MoO x heterostructures with double-well and step-well geometries. We also considere the coupling between transverse and longitudinal kinetic energy because the electron effective mass changes spatially in the MoS2/MoO x heterostructures. We find the resonant peaks show red shift with the increasing of transverse momentum, which is similar to the previous work studying the transverse-momentum-dependent transmission in GaAs/Ga1‑x Al x As double-barrier structure. We find electric field can enhance the magnitude of peaks and intensify the coupling between longitudinal and transverse momentums. Moreover, higher bias is applied to optimize resonant tunnelling condition to show negative differential effect can be observed in the MoS2/MoO x system.

  10. Effect of Mo/B atomic ratio on the properties of Mo2NiB2-based cermets

    International Nuclear Information System (INIS)

    Xie, Lang; Li, XiaoBo; Zhang, Dan; Yi, Li; Gao, XiaoQing; Xiangtan Univ.

    2015-01-01

    Using three elementary substances, Mo, Ni, and amorphous B as raw materials, four series of Mo 2 NiB 2 -based cermets with the Mo/B atomic ratio ranging from 0.9 to 1.2 were successfully prepared via reaction sintering. The effect of Mo/B atomic ratio on the microstructure and properties was studied for the cermets. The results indicate that there is a strong correlation between the Mo/B atomic ratio and properties. The transverse rupture strength of the cermets increases with an increase in Mo/B ratio and shows a maximum value of 1 872 MPa at an Mo/B atomic ratio of 1.1 and then decreases with increasing Mo/B atomic ratio. The hardness and the corrosion resistance of the cermets increase monotonically with an increase in Mo/B atomic ratio. In Mo-rich cermets with an atomic ratio of Mo/B above 1.1, a small amount Ni-Mo intermetallic compound is found precipitated at the interface of Mo 2 NiB 2 grains.

  11. Phase transitions in alloys of the Ni-Mo system

    International Nuclear Information System (INIS)

    Ustinovshikov, Y.; Shabanova, I.

    2011-01-01

    Graphical abstract: The structure of Ni-20 at.% Mo and Ni-25 at.% Mo alloys was studied by methods of TEM and XPS. It is shown that at high temperatures the tendency toward phase separation takes place in the alloys and crystalline bcc Mo particles precipitate in the liquid solution. At 900 deg. C and below, the tendency toward ordering leads to the dissolution of Mo particles and precipitation of the particles of Ni 3 Mo, Ni 2 Mo or Ni 4 Mo chemical compounds. Highlights: → 'Chemical' phase transition 'ordering-phase separation' is first discovered in alloys of the Ni-Mo system. → It is first shown that the phase separation in the alloys studied begins at temperatures above the liquidus one. → The formation of Ni 3 Mo from A1 has gone through the intervening stage of the Ni 4 Mo and Ni 2 Mo coexistence. - Abstract: The structure of Ni-20 at.% Mo and Ni-25 at.% Mo alloys heat treated at different temperatures was studied by the method of transmission electron microscopy. X-ray photoelectron spectroscopy was used to detect the sign of the chemical interaction between Ni and Mo atoms at different temperatures. It is shown that at high temperatures the tendency toward phase separation takes place. The system of additional reflections at positions {1 1/2 0} on the electron diffraction patterns testifies that the precipitation of crystalline bcc Mo particles begins in the liquid solution. At 900 deg. C and below, the tendency toward ordering leads to the precipitation of the particles of the chemical compounds. A body-centered tetragonal phase Ni 4 Mo (D1 a ) is formed in the Ni-20 at.% Mo alloy. In the Ni-25 at.% Mo alloy, the formation of the Ni 3 Mo (D0 22 ) chemical compound from the A1 solid solution has gone through the intervening stage of the Ni 4 Mo (D1 a ) and Ni 2 Mo (Pt 2 Mo) formation.

  12. Coaxial silver nanowire network core molybdenum oxide shell supercapacitor electrodes

    International Nuclear Information System (INIS)

    Yuksel, Recep; Coskun, Sahin; Unalan, Husnu Emrah

    2016-01-01

    We present a new hybrid material composed of molybdenum (IV) oxide (MoO 2 ) shell on highly conducting silver nanowire (Ag NW) core in the network form for the realization of coaxial Ag NW/MoO 2 nanocomposite supercapacitor electrodes. Ag NWs were simply spray coated onto glass substrates to form conductive networks and conformal MoO 2 layer was electrodeposited onto the Ag NW network to create binder-free coaxial supercapacitor electrodes. Combination of Ag NWs and pseudocapacitive MoO 2 generated an enhanced electrochemical energy storage capacity and a specific capacitance of 500.7 F/g was obtained at a current density of 0.25 A/g. Fabricated supercapacitor electrodes showed excellent capacity retention after 5000 cycles. The methods and the design investigated herein open a wide range of opportunities for nanowire based coaxial supercapacitors.

  13. Interstitial Mo-Assisted Photovoltaic Effect in Multilayer MoSe2 Phototransistors.

    Science.gov (United States)

    Kim, Sunkook; Maassen, Jesse; Lee, Jiyoul; Kim, Seung Min; Han, Gyuchull; Kwon, Junyeon; Hong, Seongin; Park, Jozeph; Liu, Na; Park, Yun Chang; Omkaram, Inturu; Rhyee, Jong-Soo; Hong, Young Ki; Yoon, Youngki

    2018-03-01

    Thin-film transistors (TFTs) based on multilayer molybdenum diselenide (MoSe 2 ) synthesized by modified atmospheric pressure chemical vapor deposition (APCVD) exhibit outstanding photoresponsivity (103.1 A W -1 ), while it is generally believed that optical response of multilayer transition metal dichalcogenides (TMDs) is significantly limited due to their indirect bandgap and inefficient photoexcitation process. Here, the fundamental origin of such a high photoresponsivity in the synthesized multilayer MoSe 2 TFTs is sought. A unique structural characteristic of the APCVD-grown MoSe 2 is observed, in which interstitial Mo atoms exist between basal planes, unlike usual 2H phase TMDs. Density functional theory calculations and photoinduced transfer characteristics reveal that such interstitial Mo atoms form photoreactive electronic states in the bandgap. Models indicate that huge photoamplification is attributed to trapped holes in subgap states, resulting in a significant photovoltaic effect. In this study, the fundamental origin of high responsivity with synthetic MoSe 2 phototransistors is identified, suggesting a novel route to high-performance, multifunctional 2D material devices for future wearable sensor applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. 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....

  15. Ternary alloying study of MoSi2

    International Nuclear Information System (INIS)

    Yi, D.; Li, C.; Akselsen, O.M.; Ulvensoen, J.H.

    1998-01-01

    Ternary alloying of MoSi 2 with adding a series of transition elements was investigated by X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy (TEM), and energy dispersive spectroscopy (EDS). Iron, Co, Ni, Cr, V, Ti, and Nb were chosen as alloying elements according to the AB 2 structure map or the atomic size factor. The studied MoSi 2 base alloys were prepared by the arc melting process from high-purity metals. The EDS analysis showed that Fe, Co, and Ni have no solid solubility in as-cast MoSi 2 , while Cr, V, Ti, and Nb exhibit limited solid solubilities, which were determined to be 1.4 ± 0.7, 1.4 ± 0.4, 0.4 ± 0.1, and 0.8 ± 0.1. Microstructural characterization indicated that Mo-Si-M VIII (M VIII = Fe, Co, Ni) and Mo-Si-Cr alloys have a two-phase as-cast microstructure, i.e., MoSi 2 matrix and the second-phase FeSi 2 , CoSi, NiSi 2 , and CrSi 2 , respectively. In as-cast Mo-Si-V, Mo-Si-Ti, and Mo-Si-Nb alloys, besides MoSi 2 and C40 phases, the third phases were observed, which have been identified to be (Mo, V) 5 Si 3 , TiSi 2 , and (Mo, Nb) 5 Si 3

  16. 76 FR 43576 - Amendment of Class E Airspace; Hannibal, MO

    Science.gov (United States)

    2011-07-21

    ...-0046; Airspace Docket No. 11-ACE-1] 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...

  17. Demonstration of resonant photopumping of Mo VII by Mo XII for a VUV laser near 600 Angstrom

    International Nuclear Information System (INIS)

    Ilcisin, K.J.; Aumayr, F.; Schwob, J.L.; Suckewer, S.

    1993-09-01

    We present data of experiments on the resonant photopumping of Mo VII by Mo XII as a method of generating a coherent VUV source near 600 angstrom. The experiment is based on a scheme proposed by Feldman and Reader in which the 4p 6 -- 4p 5 6s transition in Mo VII in resonantly photopumped by the 5s 2 S 1/2 -- 4p 2 P 1/2 transition in Mo XII. Results of the laser produced plasma experiments show the successful enhancement of the population of the Mo VII 4p 5 6s upper lasing level when pumped by an adjacent Mo VII plasma. No enhancement was seen in a control experiment where the Mo VII plasma was pumped by a Zr X plasma. Improvements of the intensity of the Mo XII pump source, achieved using an additional pump laser, lead to the generation of a population inversion for the VUV transition

  18. Controllable synthesis of carbon nanotubes by changing the Mo content in bimetallic Fe-Mo/MgO catalyst

    International Nuclear Information System (INIS)

    Xu Xiangju; Huang Shaoming; Yang Zhi; Zou Chao; Jiang Junfan; Shang Zhijie

    2011-01-01

    Research highlights: → Increasing the Mo content in the Fe-Mo/MgO catalysts resulted in an increase in wall number, diameter and growth yield of carbon nanotubes. → The Fe interacts with MgO to form complex (MgO) x (FeO) 1-x (0 4 and relative large metal Mo particles can be generated after reduction. → The avalanche-like reduction of MgMoO 4 makes the catalyst particles to be small thus enhances the utilize efficiency of Fe nanoparticles. - Abstract: A series of Fe-Mo/MgO catalysts with different Mo content were prepared by combustion method and used as catalysts for carbon nanotube (CNT) growth. Transmission electron microscopy studies of the nanotubes show that the number of the CNT walls and the CNT diameters increase with the increasing of Mo content in the bimetallic catalyst. The growth yield determined by thermogravimetric analysis also follows the trend: the higher the Mo content, the higher the yield of the CNTs. However, the increase of Mo content leads to the lower degree of graphitization of CNTs. A comparative study on the morphology and catalytic functions of Fe/MgO, Mo/MgO and Fe-Mo/MgO catalysts was carried out by scanning electron microscopy and X-ray diffraction. It is found that the Fe interacts with MgO to form complexes and is then dispersed into the MgO support uniformly, resulting in very small Fe nanoparticles after reduction. The Mo interacts with MgO to form stoichiometry compound MgMoO 4 and relative large metal Mo particles can be generated after reduction. High yield CNTs with small diameter can be generated from Fe-Mo/MgO because the avalanche-like reduction of MgMoO 4 makes the catalyst particles to be small thus enhances the utilize efficiency of Fe nanoparticles.

  19. 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.

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

    International Nuclear Information System (INIS)

    Bhattacharjee, Ashis Kumar; Touheed, Md.; Ahmed, Mesbahuddin; Halder, A.; Mookerjee, A.

    2003-06-01

    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. (author)

  1. 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 ...

  2. 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)

  3. 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.

  4. Study of the activation of targets containing Mo for the production of 99Mo by the 98Mo(n,γ)99Mo nuclear reaction and the behaviour of the radionuclidic impurities of the process

    International Nuclear Information System (INIS)

    Nieto, Renata Correa

    1998-01-01

    The most used radioisotope in Nuclear Medicine is 99m Tc, in the 99 Mo- 99m Tc generator form. 99 Mo can be produced by several nuclear reactions in reactors and cyclotrons. The cyclotron production is not technically and economically viable. The production in the reactor can be done in two different ways: by the fission of 235 U and by 98 Mo(n,γ) 99 Mo reaction. A project for the production of 99 Mo by the activation of Mo and the preparation of gel type generators is under development at the 'Instituto de Pesquisas Energeticas e Nucleares'. In the present work, the radionuclidic impurities produced in the activation of MOO 3 and MoZr gel were evaluated, and these represent the two possible ways of preparing the gel of MoZr. A target of metallic Mo was also studied. The radionuclidic purity of 99m Tc eluted from generators prepared in these ways was also measured and compared with the generators prepared with fission 99 Mo. The results showed that, by all the parameters analysed, the best way of preparing the generator of 99 Mo - 99m Tc is the irradiation of MOO 3 and further preparation of the gel and the generators. (author)

  5. Holey Reduced Graphene Oxide Coupled with an Mo2 N-Mo2 C Heterojunction for Efficient Hydrogen Evolution.

    Science.gov (United States)

    Yan, Haijing; Xie, Ying; Jiao, Yanqing; Wu, Aiping; Tian, Chungui; Zhang, Xiaomeng; Wang, Lei; Fu, Honggang

    2018-01-01

    An in situ catalytic etching strategy is developed to fabricate holey reduced graphene oxide along with simultaneous coupling with a small-sized Mo 2 N-Mo 2 C heterojunction (Mo 2 N-Mo 2 C/HGr). The method includes the first immobilization of H 3 PMo 12 O 40 (PMo 12 ) clusters on graphite oxide (GO), followed by calcination in air and NH 3 to form Mo 2 N-Mo 2 C/HGr. PMo 12 not only acts as the Mo heterojunction source, but also provides the Mo species that can in situ catalyze the decomposition of adjacent reduced GO to form HGr, while the released gas (CO) and introduced NH 3 simultaneously react with the Mo species to form an Mo 2 N-Mo 2 C heterojunction on HGr. The hybrid exhibits superior activity towards the hydrogen evolution reaction with low onset potentials of 11 mV (0.5 m H 2 SO 4 ) and 18 mV (1 m KOH) as well as remarkable stability. The activity in alkaline media is also superior to Pt/C at large current densities (>88 mA cm -2 ). The good activity of Mo 2 N-Mo 2 C/HGr is ascribed to its small size, the heterojunction of Mo 2 N-Mo 2 C, and the good charge/mass-transfer ability of HGr, as supported by a series of experiments and theoretical calculations. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Theoretical calculations of valence states in Fe-Mo compounds

    International Nuclear Information System (INIS)

    Estrada, F; Navarro, O; Noverola, H; Suárez, J R; Avignon, M

    2014-01-01

    The half-metallic ferromagnetic double perovskite compound Sr 2 FeMoO 6 is considered as an important material for spintronic applications. It appears to be fundamental to understand the role of electronic parameters controlling the half-metallic ground state. Fe-Mo double perovskites usually present some degree of Fe/Mo disorder which generally increases with doping. In this work, we study the valence states of Fe-Mo cations in the off-stoichiometric system Sr 2 Fe 1+x Mo 1−x O 6 (−1 ≤ x ≤ 1/3) with disorder. Our results for Fe and Mo valence states are obtained using the Green functions and the renormalization perturbation expansion method. The model is based on a correlated electron picture with localized Fe-spins and conduction Mo-electrons interacting with the local spins via a double-exchange-type mechanism

  7. Phase formation in the Li2MoO4-Rb2MoO4-Ln2(MoO4)3 systems and the properties of LiRbLn2(MoO4)4

    International Nuclear Information System (INIS)

    Basovich, O.M.; Khajkina, E.G.; Vasil'ev, E.V.; Frolov, A.M.

    1995-01-01

    Phase equilibria within subsolidus range of ternary salt systems Li 2 MoO 4 -Rb 2 MoO 4 -Ln 2 (MoO 4 ) 4 (Ln - Nd, Er) are analyzed. Formation of ternary molybdate LiRbNd 2 (MoO 4 ) 4 is proved along LiNd(MoO 4 ) 2 -RbNd(MoO 4 )-2 cross-section. Phase diagram of this cross-section is plotted. Similar compounds are synthesized for Ln = La-Eu. The parameters of their monoclinic elementary cells are determined. Luminescent properties of LiRbLa 2 (MoO 4 ) 4 -Nd 3+ are studied. 17 refs., 4 figs., 2 tabs

  8. Successful labeling of 99mTc-MDP using 99mTc separated from 99Mo produced by 100Mo(n,2n)99Mo

    International Nuclear Information System (INIS)

    Nagai, Yasuki; Hatsukawa, Yuichi; Kin, Tadahiro; Hashimoto, Kazuyuki; Motoishi, Shoji; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Sato, Yuichi; Sato, Norihito; Ohta, Akio; Yamabayashi, Hisamichi; Tanase, Masakazu; Fujisaki, Saburo; Kawauchi, Yukimasa; Teranaka, Tomoyuki; Takeuchi, Nobuhiro; Igarashi, Takashi

    2011-01-01

    We have for the first time succeeded in separating 99m Tc from a MoO 3 sample irradiated with accelerator neutrons free from any radioactive impurities and in formulating 99m Tc-methylene diphosphonate ( 99 mTc-MDP). 99 Mo, the mother nuclide of 99m Tc, was produced by the 100 Mo(n,2n) 99 Mo reaction using about 14 MeV neutrons provided by the 3 H(d,n) 4 He reaction at the Fusion Neutronics Source of Japan Atomic Energy Agency. The 99m Tc was separated from 99 Mo by sublimation and its radionuclide purity was confirmed to be higher than 99.99% by γ-spectroscopy. The labeling efficiency of 99m Tc-MDP was shown to be higher than 99% by thin-layer chromatography. These values exceed the United States Pharmacopeia requirements for a fission product, 99 Mo. Consequently, a 99m Tc radiopharmaceutical preparation formed by using the mentioned 99 Mo can be a promising substitute for the fission product 99 Mo, which is currently produced using a highly enriched uranium target in aging research reactors. A longstanding problem to ensure a reliable and constant supply of 99 Mo in Japan can be partially mitigated. (author)

  9. Study of the 93Mo nucleus

    International Nuclear Information System (INIS)

    Mittal, V.K.; Avasthi, D.K.; Kumar, A; Govil, I.M.

    1981-01-01

    The level structure of 93 Mo has been studied through 93 Nb(p,nγ) reaction at incident proton energy of 4.2 MeV. Spin assignments and multipole mixing ratios for various levels and transitions have been deduced from the analysis of angular distributions of singles γ-ray spectra. Lifetimes of various levels have been obtained using Doppler Shift Attenuation (DSA) method. (author)

  10. MoS{sub 2} spaser

    Energy Technology Data Exchange (ETDEWEB)

    Jayasekara, Charith, E-mail: charith.jayasekara@monash.edu; Premaratne, Malin [Advanced Computing and Simulation Laboratory (A chi L), Department of Electrical and Computer Systems Engineering, Monash University, Clayton, Victoria 3800 (Australia); Gunapala, Sarath D. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); Stockman, Mark I. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

    2016-04-07

    We present a comprehensive analysis of a spaser made of a circular shaped highly doped molybdenum disulfide (MoS{sub 2}) resonator. “Spaser” is an acronym for “surface plasmon amplification by stimulated emission of radiation”–a nanoscale source of surface plasmons generated by stimulated emission in a plasmonic resonator which receives energy nonradiatively. By considering localized surface plasmon modes, operation characteristics of the model are analysed, and tunability of the design is demonstrated. We find the optimum geometric and material parameters of the spaser that provides efficient outputs and carryout a comparative analysis with a similar circular spaser made of graphene. Owing to physical and chemical properties of MoS{sub 2} and the active medium, the proposed design delivers efficient outputs in terms of spaser mode energy, operating thresholds, Q-factor, and electric field amplitude. Lower operating thresholds and higher mode energies are notable advantages of the design. Owing to having many superior features to existing similar designs, this MoS{sub 2} spaser may be much suited for applications in nanoplasmonic devices.

  11. Physicochemical investigation of Bi2MoO6 solid-phase interaction with Sm2MoO6

    International Nuclear Information System (INIS)

    Khajkina, E.G.; Kovba, L.M.; Bazarova, Zh.G.; Khal'baeva, K.M.; Khakhinov, V.V.; Mokhosoev, M.V.

    1986-01-01

    Bi 2 MoO 6 -Sm 2 MoO 6 interaction in the temperature range of 700-1000 deg C is studied using X-ray phase analysis and vibrational spectroscopy. Formation of monoclinic solid solutions based on γ'-Bi 2 MoO 6 and B 2-x Sm x MoO 6 varied composition phase with α-Ln 2 MoO 6 structure which homogeneity region extent at 1000 deg C constitutes ∼ 50 mol % (0.7≤x≤1.7) is stated. Crystallographic characteristics of the synthesized phases are determined

  12. Suppressing band gap of MoS{sub 2} by the incorporation of four- and eight-membered rings

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liyan; Zhang, Tingting, E-mail: ttzhang@hytc.edu.cn [Huaiyin Normal University, School of Physics and Electronic & Electrical Engineering, and Jiangsu Key Laboratory of Modern Measurement Technology and Intelligent Systems (China)

    2015-05-15

    A stable planar allotrope of MoS{sub 2}, formed by introducing four- and eight-membered rings into its hexagonal network (H468), is identified to be a narrow direct-band-gap semiconductor by first principle calculations, which is remarkably different from the large band gap semiconductor of conventional MoS{sub 2} and also the zero band gap allotrope consisting of four- and eight-membered rings (H48) only. The medium-sized direct band gap indicates that H468 would find applications in nanoelectronics and near-infrared optoelectronic devices. Furthermore, the distinctive simulated scanning tunneling microscope images under positive and negative biases might be a unique characteristic for the experimental identification of such an allotrope of MoS{sub 2}.

  13. 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.

  14. Deoxygenation of glycolaldehyde and furfural on Mo2C/Mo(100)

    Science.gov (United States)

    McManus, Jesse R.; Vohs, John M.

    2014-12-01

    The desire to produce fuels and chemicals in an energy conscious, environmentally sympathetic approach has motivated considerable research on the use of cellulosic biomass feedstocks. One of the major challenges facing the utilization of biomass is finding effective catalysts for the efficient and selective removal of oxygen from the highly-oxygenated, biomass-derived platform molecules. Herein, a study of the reaction pathways for the biomass-derived platform molecule furfural and biomass-derived sugar model compound glycolaldehyde provides insight into the mechanisms of hydrodeoxygenation (HDO) on a model molybdenum carbide catalyst, Mo2C/Mo(100). Using temperature programmed desorption (TPD) and high resolution electron energy loss spectroscopy (HREELS), it was found that the Mo2C/Mo(100) catalyst was active for selective deoxygenation of the aldehyde carbonyl by facilitating adsorption of the aldehyde in an η2(C,O) bonding configuration. Furthermore, the catalyst showed no appreciable activity for furanic ring hydrogenation, highlighting the promise of relatively inexpensive Mo2C catalysts for selective HDO chemistry.

  15. 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.

  16. 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

  17. Effects of Mo Content on Microstructure and Mechanical Property of PH13-8Mo Martensitic Precipitation-Hardened Stainless Steel

    Science.gov (United States)

    Yubing, Pei; Tianjian, Wang; Zhenhuan, Gao; Hua, Fan; Gongxian, Yang

    This paper introduces the effects of Mo content on microstructure and mechanical property of PH13-8Mo martensitic precipitation-hardened stainless steel which is used for LP last stage blade in steam turbine. Thermodynamic software Thermo-Calc has been used to calculate precipitation temperature and the mass fraction of precipitated phases in PH13-8Mo steel with different Mo content. The result shows that when the mass of Mo is below 0.6wt.%, chi-phase mu-phase and sigma-phase could disappear. The microstructure and mechanical property of high Mo PH13-8Mo (Mo=0.57wt.%) and low Mo PH13-8Mo (Mo=2.15wt.%)have been investigated in different heat treatments. The investigations reveal that austenitizing temperature decrease with the reduce of Mo content, so the optimum solution temperature for low Mo PH13-8Mo is lower than that for high Mo PH13-8Mo.The influence of solution temperature on grain size is weakened with the increase of Mo content, Mo rich carbides could retard coarsening of grain. An enormous amount of nano-size uniformly distributed β-NiAl particles are found in both kinds of steels using transmission electron microscopy, they are the most important strengthening phase in PH13-8Mo.

  18. Mo isotope fractionation during hydrothermal evolution of porphyry Cu systems

    Science.gov (United States)

    Shafiei, Behnam; Shamanian, GholamHossein; Mathur, Ryan; Mirnejad, Hassan

    2015-03-01

    We present Mo isotope compositions of molybdenite types from three successive stages of ore deposition in several porphyry copper deposits of the Kerman region, Iran. The data provide new insights into controlling processes on Mo isotope fractionation during the hydrothermal evolution of porphyry systems. The Mo isotope compositions of 27 molybdenite samples show wide variations in δ97Mo ranging from -0.37 to +0.92 ‰. The data reveal that molybdenites in the early and transitional stages of mineralization (preferentially 2H polytypes; δ97Mo mean = 0.35 ‰) have higher δ97Mo values than late stage (mainly 3R polytypes; δ97Mo mean = 0.02 ‰) molybdenites. This trend suggests that fractionation of Mo isotopes occurred in high-temperature stages of mineralization and that hydrothermal systems generally evolve towards precipitation of molybdenite with lower δ97Mo values. Taking into account the genetic models proposed for porphyry Cu deposits along with the temperature-dependent fractionation of Mo isotope ratios, it is proposed that large variations of Mo isotopes in the early and the transitional stages of ore deposition could be controlled by the separation of the immiscible ore-forming fluid phases with different density, pH, and ƒO2 properties (i.e., brine and vapor). The fractionation of Mo isotopes during fluid boiling and Rayleigh distillation processes likely dominates the Mo isotope budget of the remaining ore-forming fluids for the late stage of mineralization. The lower δ97Mo values in the late stage of mineralization can be explained by depletion of the late ore-forming hydrothermal solutions in 97Mo, as these fluids have moved to considerable distance from the source. Finally, the relationship observed between MoS2 polytypes (2H and 3R) and their Mo isotopic compositions can be explained by the molecular vibration theory, in which heavier isotopes are preferentially partitioned into denser primary 2H MoS2 crystals.

  19. Structural investigations of borosilicate glasses containing MoO{sub 3} by MAS NMR and Raman spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Caurant, D., E-mail: daniel-caurant@enscp.f [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Ecole Nationale Superieure de Chimie de Paris (ENSCP, ParisTech), 11 rue Pierre et Marie Curie, 75231 Paris (France); Majerus, O.; Fadel, E.; Quintas, A. [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Ecole Nationale Superieure de Chimie de Paris (ENSCP, ParisTech), 11 rue Pierre et Marie Curie, 75231 Paris (France); Gervais, C. [Laboratoire de Chimie de la Matiere Condensee de Paris, UMR-CNRS 7574, Universite Pierre et Marie Curie, 75252 Paris (France); Charpentier, T. [CEA, IRAMIS, Service Interdisciplinaire sur les Systemes Moleculaires et Materiaux, CEA Saclay, 91191 Gif-sur-Yvette (France); Neuville, D. [Physique des Mineraux et des Magmas, UMR-CNRS 7047, Institut de Physique du Globe, place Jussieu, 75252 Paris (France)

    2010-01-01

    High molybdenum concentration in glass compositions may lead to alkali and alkaline-earth molybdates crystallization during melt cooling that must be controlled particularly during the preparation of highly radioactive nuclear glassy waste forms. To understand the effect of molybdenum addition on the structure of a simplified nuclear glass and to know how composition changes can affect molybdates crystallization tendency, the structure of two glass series belonging to the SiO{sub 2}-B{sub 2}O{sub 3}-Na{sub 2}O-CaO-MoO{sub 3} system was studied by {sup 29}Si, {sup 11}B, {sup 23}Na MAS NMR and Raman spectroscopies by increasing MoO{sub 3} or B{sub 2}O{sub 3} concentrations. Increasing MoO{sub 3} amount induced an increase of the silicate network reticulation but no significant effect was observed on the proportion of BO{sub 4}{sup -} units and on the distribution of Na{sup +} cations in glass structure. By increasing B{sub 2}O{sub 3} concentration, a strong evolution of the distribution of Na{sup +} cations was observed that could explain the evolution of the nature of molybdate crystals (CaMoO{sub 4} or Na{sub 2}MoO{sub 4}) formed during melt cooling.

  20. Facile construction of 3D graphene/MoS2 composites as advanced electrode materials for supercapacitors

    Science.gov (United States)

    Sun, Tianhua; Li, Zhangpeng; Liu, Xiaohong; Ma, Limin; Wang, Jinqing; Yang, Shengrong

    2016-11-01

    Flower-like molybdenum disulfide (MoS2) microstructures are synthesized based on three-dimensional graphene (3DG) skeleton via a simple and facile one-step hydrothermal method, aiming at constructing series of novel composite electrode materials of 3DG/MoS2 with high electrochemical performances for supercapacitors. The electrochemical properties of the samples are evaluated by cyclic voltammetry and galvanostatic charge/discharge tests. Specifically, the optimal 3DG/MoS2 composite exhibits remarkable performances with a high specific capacitance of 410 F g-1 at a current density of 1 A g-1 and an excellent cycling stability with ca. 80.3% capacitance retention after 10,000 continuous charge-discharge cycles at a high current density of 2 A g-1, making it adaptive for high-performance supercapacitors. The enhanced electrochemical performances can be ascribed to the combination of 3DG and flower-like MoS2, which provides excellent charge transfer network and electrolyte diffusion channels while effectively prevents the collapse, aggregation and morphology change of active materials during charge-discharge process. The results demonstrate that 3DG/MoS2 composite is one of the attractive electrode materials for supercapacitors.

  1. Microstructure and Room-Temperature Mechanical Properties of FeCrMoVTi x High-Entropy Alloys

    Science.gov (United States)

    Guo, Jun; Huang, Xuefei; Huang, Weigang

    2017-07-01

    FeCrMoVTi x ( x values represent the molar ratio, where x = 0, 0.5, 1.0, 1.5, and 2.0) high-entropy alloys were prepared by a vacuum arc melting method. The effects of Ti element on the microstructure and room-temperature mechanical properties of the as-cast FeCrMoVTi x alloys were investigated. The results show that the prepared alloys exhibited typical dendritic microstructure and the size of the microstructure became fine with increasing Ti content. The FeCrMoV alloy exhibited a single body-centered cubic structure (BCC1) and the alloys prepared with Ti element exhibited BCC1 + BCC2 mixed structure. The new BCC2 phase is considered as (Fe, Ti)-rich phase and was distributed in the dendrite region. With the increase of Ti content, the volume fraction of the BCC2 phase increased and its shape changed from a long strip to a network. For the FeCrMoV alloy, the fracture strength, plastic strain, and hardness reached as high as 2231 MPa, 28.2%, and 720 HV, respectively. The maximum hardness of 887 HV was obtained in the FeCrMoVTi alloy. However, the fracture strength, yield stress, and plastic strain of the alloys decreased continuously as Ti content increased. In the room-temperature compressive test, the alloys showed typical brittle fracture characteristics.

  2. Two-dimensional MoS2-graphene hybrid nanosheets for high gravimetric and volumetric lithium storage

    Science.gov (United States)

    Deng, Yakai; Ding, Lixin; Liu, Qixing; Zhan, Liang; Wang, Yanli; Yang, Shubin

    2018-04-01

    Two-dimensional (2D) MoS2-graphene (MoS2-G) hybrid is fabricated simultaneously and scalablely with an efficient electrochemical exfoliation approach from the combined bulk MoS2-graphite wafer. The as-prepared 2D MoS2-G hybrid is tightly covered with each other with lateral sizes of 600 nm to few micrometers and can be directly assembled to flexible films for lithium storage. When used as anode material for lithium ion battery, the resultant MoS2-G hybrid film exhibits both high gravimetric (750 mA h g-1 at 50 mA g-1) and volumetric capacities (1200 mA h cm-3 at 0.1 mA cm-2). Such excellent electrochemical performance should attributed to the unique 2D structure and good conductive graphene network, which not only facilitates the diffusion of lithium ions, but also improves the fast transfer of electrons, satisfying the kinetics requirements for rapid lithium storage.

  3. Development of Mo recycle technique from generator materials

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, Masataka; Kurosawa, Makoto; Kimura, Akihiro; Nishikata, Kaori; Tsuchiya, Kunihiko [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan); Kakei, Sadanori; Yoshinaga, Hideo [Taiyo Koko Corp., Ako Laboratory, Ako, Hyogo (Japan)

    2012-03-15

    The domestic {sup 99}Mo production by the (n,{gamma}) method is proposed in JMTR because of low amount of radioactive wastes and easy {sup 99}Mo/{sup 99m}Tc production process. For the development of domestic production, it is necessary to use the enriched {sup 98}MoO{sub 3}, which is very expensive, for high specific activity of {sup 99}Mo. A large amount of used PZC/PTC embraced {sup 98}Mo is also generated after the decay of {sup 99}Mo. JAEA and Taiyo Koko is proposed to recover molybdenum from the used PZC/PTC for an effective use of resources and reduction of radioactive wastes. Preliminary experiments of Mo recycling with un-irradiated MoO{sub 3} were carried out by the elution and sublimation methods. From the results, Mo recovery rate from the PZC/PTC was more than 95% by two kinds of methods. The prospects are bright for Mo recycle and reduction of radioactive wastes using these methods. (author)

  4. 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.

  5. 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.%.

  6. Gold nanoparticles on MoS2 layered crystal flakes

    International Nuclear Information System (INIS)

    Cao, Wei; Pankratov, Vladimir; Huttula, Marko; Shi, Xinying; Saukko, Sami; Huang, Zhongjia; Zhang, Meng

    2015-01-01

    Inorganic layered crystal MoS 2 is considered as one of the most promising and efficient semiconductor materials for future transistors, photoelectronics, and electrocatalysis. To boost MoS 2 -based material applications, one direction is to grow physically and chemically reactive nanoparticles onto MoS 2 . Here we report on a simple route to synthesis crystalized MoS 2 –Au complexes. The gold nanoparticles were grown on MoS 2 flakes through a wet method in the oxygen free environment at room temperature. Nanoparticles with diameters varying from 9 nm to 429 nm were controlled by the molar ratios of MoS 2 and HAuCl 4 precursors. MoS 2 host flakes keep intrinsic honeycomb layered structures and the Au nanoparticles cubic-center crystal microstructures. From product chemical states analysis, the synthesis was found driven by redox reactions between the sulphide and the chloroauric acid. Photoluminescence measurement showed that introducing Au nanoparticles onto MoS 2 stacks substantially prompted excitonic transitions of stacks, as an analogy for doping Si wafers with dopants. Such composites may have potential applications in wide ranges similar as the doped Si. - Highlights: • The Au nanoparticles were decorated on MoS 2 in oxygen free ambiences via a wet method. • The Au nanoparticles are size-controllable and crystalized. • Chemical reaction scheme was clarified. • The MoS 2 –Au complexes have strong photoluminescent properties

  7. In-situ fabrication of MoSi{sub 2}/SiC–Mo{sub 2}C gradient anti-oxidation coating on Mo substrate and the crucial effect of Mo{sub 2}C barrier layer at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun [School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084 (China); State Key Laboratory of New Ceramics and Fine Processing, Beijing 100084 (China); Gong, Qianming, E-mail: gongqianming@mail.tsinghua.edu.cn [School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084 (China); State Key Laboratory of New Ceramics and Fine Processing, Beijing 100084 (China); Shao, Yang; Zhuang, Daming [School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084 (China); State Key Laboratory of New Ceramics and Fine Processing, Beijing 100084 (China); Liang, Ji [Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Beijing 100084 (China); Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China)

    2014-07-01

    MoSi{sub 2}/SiC–Mo{sub 2}C gradient coating on molybdenum was in situ prepared with pack cementation process by two steps: (1) carburizing with graphite powder to obtain a Mo{sub 2}C layer on Mo substrate, and (2) siliconizing with Si powder to get a composite MoSi{sub 2}/SiC layer on the upper part of Mo{sub 2}C layer. The microstructure and elemental distribution in the coating were investigated with scanning electron microscopy (SEM), backscattered electron (BSE), energy dispersive spectroscopy (EDS), electron probe microanalysis (EPMA) and X-ray diffraction (XRD). Cyclic oxidation tests (at 500 °C, 1200 °C, 1400 °C and 1600 °C) demonstrated excellent oxidation resistance for the gradient composite coating and the mass loss was only 0.23% in 60 min at 1600 °C. XRD, EPMA, thermal dynamic and phase diagram analyses indicated that the Mo{sub 2}C barrier layer played the key role in slowing down the diffusion of C and Si toward inner Mo substrate at high temperature and principally this contributed to the excellent anti-oxidation for Mo besides the outer MoSi{sub 2}/SiC composite layer.

  8. In-situ fabrication of MoSi2/SiC–Mo2C gradient anti-oxidation coating on Mo substrate and the crucial effect of Mo2C barrier layer at high temperature

    International Nuclear Information System (INIS)

    Liu, Jun; Gong, Qianming; Shao, Yang; Zhuang, Daming; Liang, Ji

    2014-01-01

    MoSi 2 /SiC–Mo 2 C gradient coating on molybdenum was in situ prepared with pack cementation process by two steps: (1) carburizing with graphite powder to obtain a Mo 2 C layer on Mo substrate, and (2) siliconizing with Si powder to get a composite MoSi 2 /SiC layer on the upper part of Mo 2 C layer. The microstructure and elemental distribution in the coating were investigated with scanning electron microscopy (SEM), backscattered electron (BSE), energy dispersive spectroscopy (EDS), electron probe microanalysis (EPMA) and X-ray diffraction (XRD). Cyclic oxidation tests (at 500 °C, 1200 °C, 1400 °C and 1600 °C) demonstrated excellent oxidation resistance for the gradient composite coating and the mass loss was only 0.23% in 60 min at 1600 °C. XRD, EPMA, thermal dynamic and phase diagram analyses indicated that the Mo 2 C barrier layer played the key role in slowing down the diffusion of C and Si toward inner Mo substrate at high temperature and principally this contributed to the excellent anti-oxidation for Mo besides the outer MoSi 2 /SiC composite layer.

  9. A Security Architecture for Personal Networks

    NARCIS (Netherlands)

    Jehangir, A.

    2009-01-01

    The proliferation of personal mobile computing devices such as laptops and mo- bile phones, as well as wearable computing devices such as belt computers, digital bracelets and bio-medical sensors has created an opportunity to create a wireless network to share information and resources amongst

  10. Grotrian diagrams for highly ionized molybdenum Mo VI through Mo XLII

    International Nuclear Information System (INIS)

    Shirai, Toshizo; Sugar, J.; Wiese, W.L.

    1997-07-01

    Grotrian diagrams are presented to provide graphical overviews for 1,930 spectral lines of highly ionized molybdenum, Mo VI through Mo XLII. In the usual diagram display such as that by Bashkin and Stoner (North-Holland, Amsterdam, 1975), the density of transitions is often too high to allow each transition to be drawn separately. Here in our modified diagrams, the transitions are also represented by lines connecting the upper and lower energy levels, but the lower energy levels are extended and repeated for successive configurations as needed. As a sequence, dense packing is avoided and all lines in a multiplet can be accommodated. (author)

  11. Structural transformation of MoO3 nanobelts into MoS2 nanotubes

    International Nuclear Information System (INIS)

    Deepak, Francis Leonard; Mayoral, Alvaro; Yacaman, Miguel Jose

    2009-01-01

    The structural transformation of MoO 3 nanobelts into MoS 2 nanotubes using a simple sulfur source has been reported. This transformation has been extensively investigated using electron microscopic and spectroscopic techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), and energy-dispersive X-ray analysis (SEM-EDAX and TEM-EDX). The method described in this report will serve as a generic route for the transformation of other oxide nanostructures into the chalcogenide nanostructures. (orig.)

  12. Well-Constructed Single-Layer Molybdenum Disulfide Nanorose Cross-Linked by Three Dimensional-Reduced Graphene Oxide Network for Superior Water Splitting and Lithium Storage Property

    Science.gov (United States)

    Zhao, Yanyan; Kuai, Long; Liu, Yanguo; Wang, Pengpeng; Arandiyan, Hamidreza; Cao, Sufeng; Zhang, Jie; Li, Fengyun; Wang, Qing; Geng, Baoyou; Sun, Hongyu

    2015-01-01

    A facile one-step solution reaction route for growth of novel MoS2 nanorose cross-linked by 3D rGO network, in which the MoS2 nanorose is constructed by single-layered or few-layered MoS2 nanosheets, is presented. Due to the 3D assembled hierarchical architecture of the ultrathin MoS2 nanosheets and the interconnection of 3D rGO network, as well as the synergetic effects of MoS2 and rGO, the as-prepared MoS2-NR/rGO nanohybrids delivered high specific capacity, excellent cycling and good rate performance when evaluated as an anode material for lithium-ion batteries. Moreover, the nanohybrids also show excellent hydrogen-evolution catalytic activity and durability in an acidic medium, which is superior to MoS2 nanorose and their nanoparticles counterparts. PMID:25735416

  13. 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.

  14. 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.

  15. Effect of unlabelled monoclonal antibody (MoAb) on biodistribution of /sup 111/Indium labelled (MoAb)

    Energy Technology Data Exchange (ETDEWEB)

    Lamki, L M; Murray, J L; Rosenblum, M G; Patt, Y Z; Babaian, Richard; Unger, M W

    1988-08-01

    We have evaluated immunoscintigraphy in cancer patients using four /sup 111/In-labelled murine monoclonal antibodies (MoAb): 96.5 (anti-P97 of melanoma), ZME-018 (anti-high molecular weight antibody of melanoma), ZCE-025 (anti-CEA for colon cancer) and PAY-276 (anti-prostatic acid phosphatase for prostatic cancer). The effect of increasing the doses of unlabelled MoAb (co-infused with 1 mg labelled MoAb) on the relative body distribution of each labelled MoAb was assessed. Localization in the liver decreased significantly in all cases, with increasing MoAb dose, except for ZME-018. Localization in other organs increased significantly as the liver activity decreased. The spleen activity, however, fell in the case of MoAb ZME-018. Blood-pool activity increased with MoAb dose in all four MoAbs. These findings correlated with the rise in the detection rate of metastases, the plasma half-life, and other pharmacokinetic parameters. However, the dose level at which this correlation occurred varied with each antibody. These data demonstrate the co-infusion of unlabelled MoAb with /sup 111/In-labelled MoAb could alter the organ distribution, pharmacokinetics and tumour uptake in a favourable manner, though the degree to which this occurs depends on the antibody in question.

  16. Photo-transmutation of {sup 100}Mo to {sup 99}Mo with Laser-Compton Scattering Gamma-ray

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoung; Rehman, Haseeb ur; Kim, Yonghee [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    This paper presents a photonuclear transmutation method using laser Compton scattering (LCS) gamma-ray beam. Potential production rate (reaction rate) of 99Mo using the photonuclear (γ,n) reaction is evaluated. Rigorous optimization of the LCS spectrum has also been performed to maximize production of the 99Mo. Cyclotron proton accelerators are used worldwide to produce many short-living medical isotopes. However, few are capable of producing Mo-99 and none are suitable for producing more than a small fraction of the required amounts. More than 90% of the world's demand of 99Mo is sourced from five nuclear reactors. Two of these reactors have already been decommissioned and the rest are more than 45 years old. Relatively short half-life of the parent 99Mo requires continuous re-supply to meet the requirements of medical industry. Therefore, there is an urgent need to produce the 99Mo and 99mTc isotopes by alternative ways. One such alternative is giant dipole resonance (GDR) based photonuclear transmutation of 100Mo to 99Mo. For 99Mo production with the LCS photons using GDR-based (γ,n) reaction, the gamma-ray energy should be around 15 MeV. This study indicates that optimization of LCS spectrum by varying the electron and laser energies within practical limits can enhance the transmutation of Mo-100 to M-99 quite significantly. It has been found that irradiation time should be rather short, e.g., less than 6 hours, to maximize the weekly production of Mo-99 in the GDR-based Mo-99 production facility using the LCS photons. The analysis shows that production of 99Mo using a high-performance LCS facility offers a potentially-promising alternative for the production of 99mTc.

  17. 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

  18. Comparitive study of fluorescence lifetime quenching of rhodamine 6G by MoS2 and Au-MoS2

    Science.gov (United States)

    Shakya, Jyoti; Kasana, Parath; Mohanty, T.

    2018-04-01

    Time resolved fluorescence study of Rhodamine 6G (R6G) in the presence of Molybdenum disulfide (MoS2) nanosheets and gold doped MoS2 (Au-MoS2) have been carried out and discussed. We have analyzed the fluorescence decay curves of R6G and it is observed that Au-MoS2 is a better fluorescence lifetime quencher as compare to MoS2 nanosheets. Also, the energy transfer efficiency and energy transfer rate from R6G to MoS2 and Au-MoS2 has been calculated and found higher for Au-MoS2.

  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. Atomic scale onset of Al adhesion on Mo2BC

    International Nuclear Information System (INIS)

    Bolvardi, Hamid; Music, Denis; Schneider, Jochen M.

    2015-01-01

    We have explored interfacial interactions between a Mo–C terminated Mo 2 BC(040) surface and an Al cluster using ab initio molecular dynamics. The Al cluster is disrupted and wets the Mo 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 2 BC and an Al cluster were explored. • Al forms bonds to C constituting the onset of Al adhesion on Mo 2 BC. • These data are relevant for other carbide coatings

  1. U-Mo fuel qualification program in HANARO

    International Nuclear Information System (INIS)

    Lee, K.H.; Lee, C.S.; Kim, H.R.; Kuk, I.H.; Kim, C.K.

    2000-01-01

    Atomized U-Mo fuel has shown good performance from the results of previous out-of-pile tests and post-irradiation examinations. A qualification program of rod type U-Mo fuel is in progress and the fuel will be irradiated in HANARO. 6 gU/cm 3 U-7Mo, U-8Mo and U-9Mo are considered in this program. The laboratory test results of porosity, mechanical property, thermal conductivity, and thermal compatibility test are discussed in this paper. In parallel with this qualification program, the feasibility study on the core conversion from the present U 3 Si fuel to U-Mo in HANARO will be initiated to provide technical bases for the policy making. Several options of core conversion for HANARO are proposed and each option will be addressed briefly in terms of the operation policy, fuel management, and licensing of HANARO. (author)

  2. MoRM and Future Memories

    DEFF Research Database (Denmark)

    Rehder, Mads Middelboe; Ostrowski, Kasper

    2017-01-01

    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)....

  3. Phase formation in the Li2MoO4–K2MoO4–In2(MoO4)3 system and crystal structures of new compounds K3InMo4O15 and LiK2In(MoO4)3

    International Nuclear Information System (INIS)

    Khal’baeva, Klara M.; Solodovnikov, Sergey F.; Khaikina, Elena G.; Kadyrova, Yuliya M.; Solodovnikova, Zoya A.; Basovich, Olga M.

    2012-01-01

    XRD study of solid-phase interaction in the Li 2 MoO 4 –K 2 MoO 4 –In 2 (MoO 4 ) 3 system was performed. The boundary K 2 MoO 4 –In 2 (MoO 4 ) 3 system is an non-quasibinary join of the K 2 O–In 2 O 3 –MoO 3 system where a new polymolybdate K 3 InMo 4 O 15 isotypic to K 3 FeMo 4 O 15 was found. In the structure (a=33.2905(8), b=5.8610(1), c=15.8967(4) Å, β=90.725(1)°, sp. gr. C2/c, Z=8, R(F)=0.0407), InO 6 octahedra, Mo 2 O 7 diortho groups and MoO 4 tetrahedra form infinite ribbons {[In(MoO 4 ) 2 (Mo 2 O 7 )] 3− } ∞ along the b-axis. Between the chains, 8- to 10-coordinate potassium cations are located. A subsolidus phase diagram of the Li 2 MoO 4 –K 2 MoO 4 –In 2 (MoO 4 ) 3 system was constructed and a novel triple molybdate LiK 2 In(MoO 4 ) 3 was revealed. Its crystal structure (a=7.0087(2), b=9.2269(3), c=10.1289(3) Å, β=107.401(1)°, sp. gr. P2 1 , Z=2, R(F)=0.0280) contains an open framework of vertex-shared MoO 4 tetrahedra, InO 6 octahedra and LiO 5 tetragonal pyramids with nine- and seven-coordinate potassium ions in the framework channels. - Graphical abstract: Exploring the Li 2 MoO 4 –K 2 MoO 4 –In 2 (MoO 4 ) 3 system showed its partial non-quasibinarity and revealed new compounds K 3 InMo 4 O 15 (isotypic to K 3 FeMo 4 O 15 ) and LiK 2 In(MoO 4 ) 3 which were structurally studied. An open framework of the latter is formed by vertex-shared MoO 4 tetrahedra, InO 6 octahedra and LiO 5 tetragonal pyramids. Highlights: ► Subsolidus phase relations in the Li 2 MoO 4 –K 2 MoO 4 –In 2 (MoO 4 ) 3 system were explored. ► The K 2 MoO 4 –In 2 (MoO 4 ) 3 system is a non-quasibinary join of the K 2 O–In 2 O 3 –MoO 3 system. ► New compounds K 3 InMo 4 O 15 and LiK 2 In(MoO 4 ) 3 were obtained and structurally studied. ► K 3 InMo 4 O 15 is isotypic to K 3 FeMo 4 O 15 and carries bands of InO 6 , MoO 4 and Mo 2 O 7 units. ► An open framework of LiK 2 In(MoO 4 ) 3 is formed by polyhedra MoO 4 , InO 6 and LiO 5 .

  4. Ordering in rapidly solidified Ni/sub 2/Mo

    International Nuclear Information System (INIS)

    Kulkarni, U.D.; Dey, G.K.; Banerjee, S.

    1988-01-01

    Ordering processes in the Ni-Mo system have been a subject of several investigations. Although the ordering behaviour of the Ni/sub 4/Mo and the Ni/sub 3/Mo has been examined in detail, no such study has been reported in the case of the Ni/sub 2/Mo alloy. The lack of experimental work on ordering transformations in Ni/sub 2/Mo is presumably due to the difficulty in obtaining a single phase fcc alloy of this composition. Enhanced solid solubility of Mo in Ni, which accompanies rapid solidification processing (RSP) makes the formation of such a phase possible. The ordering processes in Ni-Mo based alloys show several remarkable features. Firstly, the alloy (15 - 28 at % Mo) quenched from the α -phase filed exhibit a short range order (SRO) characterized by the presence of intensity maxima at /1 1/2 0/ fcc positions of the reciprocal space. This state of SRO has been attributed to the occurrence of 1 1/2 O spinodal ordering in the system. Secondly, the transformation from the state of SRO to the equilibrium/metastable coherent long range ordered (LRO) structures appears to take place in a continuous manner at relatively low temperatures of aging. Three different coherent LRO structures, namely: the equilibrium Ni/sub 4/Mo (prototype structure D1/sub a/) and the metastable Ni/sub 3/Mo (DO/sub 22/) and Ni/sub 2/Mo (Pt/sub 2/Mo) structures have reported to evolve from the SRO alloy, depending upon the aging treatment and the composition of the alloy

  5. Computational identification of MoRFs in protein sequences.

    Science.gov (United States)

    Malhis, Nawar; Gsponer, Jörg

    2015-06-01

    Intrinsically disordered regions of proteins play an essential role in the regulation of various biological processes. Key to their regulatory function is the binding of molecular recognition features (MoRFs) to globular protein domains in a process known as a disorder-to-order transition. Predicting the location of MoRFs in protein sequences with high accuracy remains an important computational challenge. In this study, we introduce MoRFCHiBi, a new computational approach for fast and accurate prediction of MoRFs in protein sequences. MoRFCHiBi combines the outcomes of two support vector machine (SVM) models that take advantage of two different kernels with high noise tolerance. The first, SVMS, is designed to extract maximal information from the general contrast in amino acid compositions between MoRFs, their surrounding regions (Flanks), and the remainders of the sequences. The second, SVMT, is used to identify similarities between regions in a query sequence and MoRFs of the training set. We evaluated the performance of our predictor by comparing its results with those of two currently available MoRF predictors, MoRFpred and ANCHOR. Using three test sets that have previously been collected and used to evaluate MoRFpred and ANCHOR, we demonstrate that MoRFCHiBi outperforms the other predictors with respect to different evaluation metrics. In addition, MoRFCHiBi is downloadable and fast, which makes it useful as a component in other computational prediction tools. http://www.chibi.ubc.ca/morf/. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Atomic structure calculations of Mo XV-XL

    International Nuclear Information System (INIS)

    Kubo, Hirotaka; Sugie, Tatsuo; Shiho, Makoto; Suzuki, Yasuo; Ishii, Keishi; Maeda, Hikosuke.

    1986-06-01

    Energy levels and oscillator strengths were calculated for Mo XV - Mo XL. The computer program for atomic structure calculation, developed by Dr. Robert D. Cowan, Los Alamos National Laboratory, was used in the present work. The scaled energy parameters were empirically determined from the observed spectral data. We present wavelengths and transition probabilities of Mo XV-XL. Energy levels and spectral patterns are presented in figures that are useful for the identification of spectral lines. (author)

  7. 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)

  8. Sheet-like of Mo –Sm assembly containing [Mo (CN)8 ] and Sm ions ...

    Indian Academy of Sciences (India)

    Administrator

    421–427. © Indian Academy of Sciences. 421 ... Department of Chemistry, Nankai University, Tianjin, 300071, PR China e-mail: ... [Mo(CN)8]3– building blocks, this paper details the ..... 20601014), and National Basic Research Program of.

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

    International Nuclear Information System (INIS)

    Fulton, Lew; Cazzola, Pierpaolo; Cuenot, Francois

    2009-01-01

    The IEA published 'Energy Technology Perspectives' (ETP) in June 2008. That document reports on IEA scenarios for baseline and low-CO 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 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.

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

    International Nuclear Information System (INIS)

    Oedewald, P.; Macchi, L.; Axelsson, C.; Eitrheim, M.H.R.

    2012-02-01

    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)

  11. Linking metabolic QTLs with network and cis-eQTLs controlling biosynthetic pathways.

    Directory of Open Access Journals (Sweden)

    Adam M Wentzell

    2007-09-01

    Full Text Available Phenotypic variation between individuals of a species is often under quantitative genetic control. Genomic analysis of gene expression polymorphisms between individuals is rapidly gaining popularity as a way to query the underlying mechanistic causes of variation between individuals. However, there is little direct evidence of a linkage between global gene expression polymorphisms and phenotypic consequences. In this report, we have mapped quantitative trait loci (QTLs-controlling glucosinolate content in a population of 403 Arabidopsis Bay x Sha recombinant inbred lines, 211 of which were previously used to identify expression QTLs controlling the transcript levels of biosynthetic genes. In a comparative study, we have directly tested two plant biosynthetic pathways for association between polymorphisms controlling biosynthetic gene transcripts and the resulting metabolites within the Arabidopsis Bay x Sha recombinant inbred line population. In this analysis, all loci controlling expression variation also affected the accumulation of the resulting metabolites. In addition, epistasis was detected more frequently for metabolic traits compared to transcript traits, even when both traits showed similar distributions. An analysis of candidate genes for QTL-controlling networks of transcripts and metabolites suggested that the controlling factors are a mix of enzymes and regulatory factors. This analysis showed that regulatory connections can feedback from metabolism to transcripts. Surprisingly, the most likely major regulator of both transcript level for nearly the entire pathway and aliphatic glucosinolate accumulation is variation in the last enzyme in the biosynthetic pathway, AOP2. This suggests that natural variation in transcripts may significantly impact phenotypic variation, but that natural variation in metabolites or their enzymatic loci can feed back to affect the transcripts.

  12. Conceptual study of 99Mo production in JRR-3

    International Nuclear Information System (INIS)

    Hirose, Akira; Komeda, Masao; Kinase, Masami; Sorita, Takami; Wada, Shigeru

    2010-06-01

    We investigated the production process of 99 Mo, which is parent nuclide of 99m Tc, in JRR-3. 99m Tc is most commonly used as a radiopharmaceutical in the field of nuclear medicine. Currently the supplying of 99 Mo is only dependent on imports from foreign countries, so JAEA is aiming at domestic production of a part of 99 Mo in cooperation with the industrial arena. This report presents the technical study for the production process of 99 Mo by using the neutron radiation method of (n, γ) reaction in JRR-3. (author)

  13. Development of Commercial-scale Fission Mo-99 Production System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Kon; Lee, Suseung; Hong, Soon-Bog; Jang, Kyung-Duk; Park, Ul Jael; Lee, Jun Sig [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    These days, worldwide {sup 99} Mo supply is not only insufficient but also unstable. Because, most of the main {sup 99}Mo production reactors are more than years old and suffered from frequent and unscheduled shutdown. Therefore, movement to replace old reactors to keep stable supply is now active. Under these conditions, KAERI (Korea Atomic Energy Research Institute) is developing LEU-based fission {sup 99}Mo production process which is connected to the new research reactor (Kijang New Research Reactor, KJRR), which is being constructed in Gijang, Busan, Korea. Historically, the most fission {sup 99}Mo producers have been used highly enriched uranium (HEU) targets so far. However, to reduce the use of HEU in private sector for non-proliferation, {sup 99}Mo producers are forced to convert their HEU-based process to use low enriched uranium (LEU) targets. Economic impact of a target conversion from HEU to LEU is significant. In this study, fission {sup 99}Mo process with non-irradiated LEU targets was presented except separation and purification steps. Pre- and post-irradiation tests of the fission {sup 99}Mo target will be done in 4th quarter of 2016. For the fission Mo production process development, hot experiments with irradiated LEU targets will be done in 4th quarter of 2016. Then, verification of the production process with quality control will be followed until the commercial production of fission {sup 99}Mo scheduled in 2019.

  14. Faceted MoS2 nanotubes and nanoflowers

    International Nuclear Information System (INIS)

    Deepak, Francis Leonard; Mayoral, Alvaro; Yacaman, Miguel Jose

    2009-01-01

    A simple synthesis of novel faceted MoS 2 nanotubes (NTs) and nanoflowers (NFs) starting from molybdenum oxide and thiourea as the sulphur source is reported. The MoS 2 nanotubes with the faceted morphology have not been observed before. Further the as-synthesized MoS 2 nanotubes have high internal surface area. The nanostructures have been characterized by a variety of electron microscopy techniques. It is expected that these MoS 2 nanostrutures will find important applications in energy storage, catalysis and field emission.

  15. 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.

  16. Comparative study of NiW, NiMo and MoW prepared by mechanical alloying

    International Nuclear Information System (INIS)

    Gonzalez, G.; Sagarzazu, A.; Villalba, R.; Ochoa, J.

    2007-01-01

    The present work concern the amorphisation process induced by mechanical alloying in the NiW, NiMo and MoW systems. The alloys chosen combine a group of transition elements varying from very similar atomic radius and electronic valences (MoW) to different ones (NiW and NiMo). The three systems achieved an amorphous state after 50 h of milling. The mechanism of amorphisation proposed for NiW and NiMo was the combined effect of an excess concentration of the solute atoms entering into the structure of one of the elements and a critical concentration of defects. Continuous formation of an amorphous phase at the interface of the crystalline phase was observed during the process. MoW seems to amorphize by continuous reduction of grain size down to a critical value where the amorphisation takes place

  17. Phase equilibria in the CdMoO4-Gd2(MoO4)3 system

    International Nuclear Information System (INIS)

    Tunik, T.A.; Fedorov, N.F.; Razumovskij, S.N.

    1980-01-01

    The constitutional diagram of the CdMoO 4 -Cd 2 (MoO 4 ) 3 system has been plotted using statistical and dynamic methods as well as a complex of instrumental analysis procedures. Three major phases have been found to occur in the systems, viz.: CdMoO 4 based solid solutions that crystallize in the range from 0 to 25 mol.percent of Cd 2 (MoO 4 ) 3 and pass in transit the two-phase narrow region becoming then solid solutions having a distorted scheelite structure and existing in concentrations from 40 to 65 mol.% of Cd 2 (MoO 4 ) 3 . The entire range, in which the Cd 2 (MoO 4 ) 3 solid solutions can exist, amounts to less than 5 mol.%. Certain crystallochemical constants of the phases that occur in the system have been determined [ru

  18. 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...... correlations that develop continuously with decreasing temperature, while the characteristic time scale for the fluctuating moments decreases dramatically below T(f) is similar to 25 K. Therefore, this pure material, which possesses frustration that is purely geometrical in origin, displays a spin-glass state...

  19. Phase equilibria in the system Li2O - MoO3 - Sc2O3

    International Nuclear Information System (INIS)

    Safonov, V.V.; Chaban, N.G.; Porotnikov, N.V.

    1984-01-01

    Using the methods of DTA and X-ray phase analysis, interaction of components in the system Li 2 O-MoO 3 -Sc 2 O 3 in concentration range, adjacent to the vertex of MoO 3 , has been studied. Projection of the Li 2 MoO 4 -MoO 3 -Sc 2 (MoO 4 ) 3 system liquidus on concentrational triangle of the compositions Li 2 O-MoO 3 -Sc 2 O 3 , which consists of the fields of primary separation of Li 2 MoO 4 , Li 2 Mo 5 O 17 , Li 2 Mo 4 O 13 , MoO 3 , Sc 2 (MoO 4 ) 3 , Li 3 Sc(MoO 4 ) 3 and LiSc(MoO 4 ) 2 , is built

  20. -MoS2 Lateral Heterojunctions

    KAUST Repository

    Li, Ming-yang

    2018-02-28

    2D layered heterostructures have attracted intensive interests due to their unique optical, transport, and interfacial properties. The laterally stitched heterojunction based on dissimilar 2D transition metal dichalcogenides forms an intrinsic p–n junction without the necessity of applying an external voltage. However, no scalable processes are reported to construct the devices with such lateral heterostructures. Here, a scalable strategy, two-step and location-selective chemical vapor deposition, is reported to synthesize self-aligned WSe2–MoS2 monolayer lateral heterojunction arrays and demonstrates their light-emitting devices. The proposed fabrication process enables the growth of high-quality interfaces and the first successful observation of electroluminescence at the WSe2–MoS2 lateral heterojunction. The electroluminescence study has confirmed the type-I alignment at the interface rather than commonly believed type-II alignment. This self-aligned growth process paves the way for constructing various 2D lateral heterostructures in a scalable manner, practically important for integrated 2D circuit applications.

  1. Voltage profile, structural prediction, and electronic calculations for MgxMo6S8

    CSIR Research Space (South Africa)

    Kganyago, KR

    2003-03-01

    Full Text Available the binary Mo6S8 and MgAMo6S8 ~see Table III!, the Mo-Mo distances decrease by (0.521)%. This decrease corresponds to an an- isotropic contraction of the Mo6 octahedron. The Mo cluster of the rhombohedral compounds forms an elongated octahe- dron of symmetry...

  2. Lattice structures and electronic properties of MO/MoSe2 interface from first-principles calculations

    Science.gov (United States)

    Zhang, Yu; Tang, Fu-Ling; Xue, Hong-Tao; Lu, Wen-Jiang; Liu, Jiang-Fei; Huang, Min

    2015-02-01

    Using first-principles plane-wave calculations within density functional theory, we theoretically studied the atomic structure, bonding energy and electronic properties of the perfect Mo (110)/MoSe2 (100) interface with a lattice mismatch less than 4.2%. Compared with the perfect structure, the interface is somewhat relaxed, and its atomic positions and bond lengths change slightly. The calculated interface bonding energy is about -1.2 J/m2, indicating that this interface is very stable. The MoSe2 layer on the interface has some interface states near the Fermi level, the interface states are mainly caused by Mo 4d orbitals, while the Se atom almost have no contribution. On the interface, Mo-5s and Se-4p orbitals hybridize at about -6.5 to -5.0 eV, and Mo-4d and Se-4p orbitals hybridize at about -5.0 to -1.0 eV. These hybridizations greatly improve the bonding ability of Mo and Se atom in the interface. By Bader charge analysis, we find electron redistribution near the interface which promotes the bonding of the Mo and MoSe2 layer.

  3. First-principles study of van der Waals interactions in MoS2 and MoO3

    International Nuclear Information System (INIS)

    Peelaers, H; Van de Walle, C G

    2014-01-01

    Van der Waals interactions play an important role in layered materials such as MoS 2 and MoO 3 . Within density functional theory, several methods have been developed to explicitly include van der Waals interactions. We compare the performance of several of these functionals in describing the structural and electronic properties of MoS 2 and MoO 3 . We include functionals based on the local density or generalized gradient approximations, but also based on hybrid functionals. The coupling of the semiempirical Grimme D2 method with the hybrid functional HSE06 is shown to lead to a very good description of both structural and electronic properties. (paper)

  4. The fracture toughness and DBTT of MoB particle-reinforced MoSi2 composites

    International Nuclear Information System (INIS)

    Xiong Zhi; Wang Gang; Jiang Wan

    2005-01-01

    The room temperature fracture toughness and the high temperature DBTT of MoB particle-reinforced MoSi 2 composites were investigated using Vickers indentation technique and MSP testing method, respectively. Modified small punch (MSP) test is a method for evaluation of mechanical properties using very small specimens, and it's appropriate for the determination of strength and DBTT. It was found that the approximate fracture toughness of the composite is 1.3 times that of monolithic MoSi 2 , and its DBTT is 100 C higher than that of monolithic MoSi 2 materials. Cracks deflection is a probable mechanism responsible for this behavior. (orig.)

  5. Magnetoresistance in Co/2D MoS2/Co and Ni/2D MoS2/Ni junctions.

    Science.gov (United States)

    Zhang, Han; Ye, Meng; Wang, Yangyang; Quhe, Ruge; Pan, Yuanyuan; Guo, Ying; Song, Zhigang; Yang, Jinbo; Guo, Wanlin; Lu, Jing

    2016-06-28

    Semiconducting single-layer (SL) and few-layer MoS2 have a flat surface, free of dangling bonds. Using density functional theory coupled with non-equilibrium Green's function method, we investigate the spin-polarized transport properties of Co/2D MoS2/Co and Ni/2D MoS2/Ni junctions with MoS2 layer numbers of N = 1, 3, and 5. Well-defined interfaces are formed between MoS2 and metal electrodes. The junctions with a SL MoS2 spacer are almost metallic owing to the strong coupling between MoS2 and the ferromagnets, while those are tunneling with a few layer MoS2 spacer. Both large magnetoresistance and tunneling magnetoresistance are found when fcc or hcp Co is used as an electrode. Therefore, flat single- and few-layer MoS2 can serve as an effective nonmagnetic spacer in a magnetoresistance or tunneling magnetoresistance device with a well-defined interface.

  6. Mo-99 supply issues: Status report and lessons learned

    International Nuclear Information System (INIS)

    Ponsard, B.

    2010-01-01

    The worldwide supply of 99 Mo relies on a limited number of research reactors and processing facilities. Its production is essential for the nuclear medicine as 99m Tc, obtained from 99 Mo/ 99m Tc generators, is used in about 80% of the diagnostic nuclear imaging procedures. These applications represent yearly approximately 30 million examinations worldwide. The short half-life's of 99 Mo (66 hours) and its daughter 99m Tc (6 hours) require a regular supply of 99 Mo/ 99m Tc generators to hospitals or central radiopharmacies. Currently, there are only five nuclear reactors involved in the production of 99 Mo on industrial scale: NRU (Canada), HFR (Netherlands), BR2 (Belgium), OSIRIS (France) and SAFARI (South Africa). They irradiate highly enriched uranium targets for the production of about 95% of the available 99 Mo by four processing facilities: AECL/MDS NORDION (Canada), COVIDIEN (Netherlands), IRE (Belgium) and NTP (South Africa). However, these ageing reactors are subject to unscheduled shutdowns and longer maintenance periods making the 99 Mo supply chain vulnerable and unreliable. Several severe disruptions have been experienced since the fall 2005 due to the occurrence of problems at different stages of the supply chain: reactor outages, release of activity from processing facilities, recall of 99 Mo/ 99m Tc generators by the manufacturers, ... It is not expected that the situation will improve significantly in the near future. Therefore, several workshops have been organized in 2009 by the OECD Nuclear Energy Agency (NEA), the International Atomic Energy Agency (IAEA) and the Association of Imaging Producers and Equipment Suppliers (AIPES) to define measures that should be taken to secure the 99 Mo supply in the short, medium and long term. This paper summarizes the current status of the 99 Mo supply, discusses the ongoing plans for additional 99 Mo production capacity and outlines the issues for a reliable global supply chain. (author)

  7. Physical properties of monolithic U8 wt.%-Mo

    Science.gov (United States)

    Hengstler, R. M.; Beck, L.; Breitkreutz, H.; Jarousse, C.; Jungwirth, R.; Petry, W.; Schmid, W.; Schneider, J.; Wieschalla, N.

    2010-07-01

    As a possible high density fuel for research reactors, monolithic U8 wt.%-Mo ("U8Mo") was examined with regard to its structural, thermal and electric properties. X-ray diffraction by the Bragg-Brentano method was used to reveal the tetragonal lattice structure of rolled U8Mo. The specific heat capacity of cast U8Mo was determined by differential scanning calorimetry, its thermal diffusivity was measured by the laser flash method and its mass density by Archimedes' principle. From these results, the thermal conductivity of U8Mo in the temperature range from 40 °C to 250 °C was calculated; in the measured temperature range, it is in good accordance with literature data for UMo with 8 and 9 wt.% Mo, is higher than for 10 wt.% Mo and lower than for 5 wt.% Mo. The electric conductivity of rolled and cast U8Mo was measured by a four-wire method and the electron based part of the thermal conductivity calculated by the Wiedemann-Frantz law. Rolled and cast U8Mo was irradiated at about 150 °C with 80 MeV 127I ions to receive the same iodine ion density in the damage peak region as the fission product density in the fuel of a typical high flux reactor after the targeted nuclear burn-up. XRD analysis of irradiated U8Mo showed a change of the lattice parameters as well as the creation of UO 2 in the superficial sample regions; however, a phase change by irradiation was not observed. The determination of the electron based part of the thermal conductivity of the irradiated samples failed due to high measurement errors which are caused by the low thickness of the damage region in the ion irradiated samples.

  8. Design of a type - a transport package for 99Mo-99mTc Coltech generator

    International Nuclear Information System (INIS)

    Kothalkar, Chetan; Suryanarayana, G.V.; Dey, A.C.; Sachdev, S.S.; Choughule, N.; Murali, S.

    2012-01-01

    BRIT is launching a new product called 99 Mo- 99m Tc Coltech generator. The Coltech generator is a devise designed for the transport of 99 Mo radioisotope adsorbed on the acidic alumina in a sealed glass column (max dimensions: 13 mm diameter, 70 mm height) as the primary containment. At hospital end, 99m Tc, the daughter product of 99 Mo, can be eluted out from the generator using saline. The active column is fitted with a leak proof network of stainless steel needles. The glass column carrying 99 Mo is housed inside a lead shielding having minimum thickness of 50 mm all around, which serves as secondary containment. The shielding is housed inside the ABS shell which acts as tertiary containment, also provides protection to the needles, filters etc. Total weight of the generator is 16 kg. Based on the AERB code SC/TR-1 (being revised), 99 Mo- 99m Tc Coltech generator will be transported in a Type-A transport container. A transport package has been designed by following the code SC/TR-1. Principle design of the package is based on the package for transportation of the similar generator produced by POLATOM, Poland and the package is approved by the Polish regulatory authority. Components are manufactured locally taking care of lndian conditions. The package comprised of a MS drum (HOBBOCK) with tamper proof lockable MS lid and a handle to assist in lifting. For absorbing the shock during transportation, the generator assembly is packed inside the two pieces EPS top and bottom support. The package has been designed for transportation by all modes of transport. Since radioactive material is solid in form and sealed a glass column, it has been designed to sustain a free drop test of 1.2 m, in addition to other tests specified in SC/TR-1. During trial batches upto ∼ 1 Ci of 99 Mo generators were produced, packed in the same Type-A package and supplied to local nuclear medicine center RMC, Mumbai in BRIT vehicle in consultation with AERB. The radiometry of the packages

  9. Thermal expansion studies on Th(MoO4)2, Na2Th(MoO4)3 and Na4Th(MoO4)4

    International Nuclear Information System (INIS)

    Keskar, Meera; Krishnan, K.; Dahale, N.D.

    2008-01-01

    Thermal expansion behavior of Th(MoO 4 ) 2 , Na 2 Th(MoO 4 ) 3 and Na 4 Th(MoO 4 ) 4 was studied under vacuum in the temperature range of 298-1123 K by high temperature X-ray diffractometer. Th(MoO 4 ) 2 was synthesized by reacting ThO 2 with 2 mol of MoO 3 , at 1073 K in air and Na 2 Th(MoO 4 ) 3 and Na 4 Th(MoO 4 ) 4 were prepared by reacting Th(MoO 4 ) 2 with 1 and 2 mol of Na 2 MoO 4 , respectively at 873 K in air. The XRD data of Th(MoO 4 ) 2 was indexed on orthorhombic system where as XRD data of Na 2 Th(MoO 4 ) 3 and Na 4 Th(MoO 4 ) 4 were indexed on tetragonal system. The lattice parameters and cell volume of all the three compounds, fit into polynomial expression with respect to temperature, showed positive thermal expansion (PTE) up to 1123 K. The average value of thermal expansion coefficients for Th(MoO 4 ) 2 , Na 2 Th(MoO 4 ) 3 and Na 4 Th(MoO 4 ) 4 were determined from the high temperature data

  10. Study of the water-gas shift reaction on Mo2C/Mo catalytic coatings for application in microstructured fuel processors

    NARCIS (Netherlands)

    Rebrov, E.V.; Kuznetsov, S.A.; Croon, de M.H.J.M.; Schouten, J.C.

    2007-01-01

    The activity and stability of two types of molybdenum carbide coatings deposited on molybdenum substrates (Mo2C/Mo) were compared in the water-gas shift reaction at 513–631 K. The activity of the Mo2C/Mo coatings obtained by carburization of preoxidized molybdenum substrates in a CH4/H2 mixture at

  11. LEUbased Fission Mo-99 Process with Reduced Solid Wastes

    International Nuclear Information System (INIS)

    Lee, Seungkon; Lee, Suseung; Jung, Sunghee; Hong, Soonbog; Jang, Kyungduk; Choi, Sang Mu; Lee, Jun Sig; Lim, Incheol

    2014-01-01

    99m Tc emits 140 keV of very low gamma-ray radiation energy, as low as conventional diagnostic X-ray, and has short half-life of 6.0058 hours. Therefore, as radioactive tracer, 99m Tc provides high quality diagnostic images but keeps total patient radiation exposure low. Depending on the tagging pharmaceuticals and procedures, 99m Tc can be applied for the diagnostics of various target organs and diseases: brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood and tumors. More than 95% of 99 Mo is produced through fission of 235 U worldwide because, 99m o generated from the fission (fission 99 Mo) exhibits very high specific activity (<100 Ci/g). Over 90% of fission 99 Mo producers have been used highly enriched uranium (HEU) targets so far. However, the IAEA recommends the use of low enriched uranium (LEU) to the 99 Mo producers for nonproliferation reason. These days, worldwide 99 Mo supply is not only insufficient but also unstable. Because, most of the main 99 Mo production reactors are about 50 years old and suffered from frequent and unscheduled shutdown. Planned weekly productivity of 2000 Ci fission 99 Mo, in a 6-day reference, will cover 100% domestic demand of Korea, as well as 20% of international market. It is expected to replace 4.3 million USD ($800/Ci) of 99 Mo import for domestic market while exporting 82.8 million USD for world market, annually

  12. Mullite/Mo interfaces formed by Intrusion bonding

    Energy Technology Data Exchange (ETDEWEB)

    Bartolome, Jose F.; Diaz, Marcos; Moya, Jose S.; Saiz, Eduardo; Tomsia, Antoni P.

    2003-04-30

    The microstructure and strength of Mo/mullite interfaces formed by diffusion bonding at 1650 C has been analyzed. Interfacial metal-ceramic interlocking contributes to flexural strength of approx. 140 MPa as measured by 3 point bending. Saturation of mullite with MoO2 does not affect the interfacial strength.

  13. Mo-Si-B-Based Coatings for Ceramic Base Substrates

    Science.gov (United States)

    Perepezko, John Harry (Inventor); Sakidja, Ridwan (Inventor); Ritt, Patrick (Inventor)

    2015-01-01

    Alumina-containing coatings based on molybdenum (Mo), silicon (Si), and boron (B) ("MoSiB coatings") that form protective, oxidation-resistant scales on ceramic substrate at high temperatures are provided. The protective scales comprise an aluminoborosilicate glass, and may additionally contain molybdenum. Two-stage deposition methods for forming the coatings are also provided.

  14. Preparation of a gel of zirconium molybdate for use in the generators of 99 Mo - 99m Tc prepared with 99 Mo produced by the 98 Mo(n,γ)99 Mo reaction

    International Nuclear Information System (INIS)

    Osso Junior, Joao A.; Lima, Ana Lucia V.P.; Silva, Nestor C. da; Nieto, Renata C.; Velosa, Adriana C. de

    1998-01-01

    IPEN develops a project concerning the preparation of a gel of Zirconium Molybdate for use in the generators of 99 Mo- 99m Tc . 99m Tc is the most used radioisotope in nuclear medicine diagnosis procedures and nowadays the generators are being prepared with imported 99 Mo, produced by 235 U fission. The production of 99 Mo by the 98 Mo(n, γ) 99 Mo reaction is now possible because of the power upgrade of IPEN's IEA-R1 reactor, from 2 to 5 MW. This work describes the preparation method of Zirconium Molybdate gel that will be used in the 99 Mo- 99m Tc generators. The gel is prepared by the chemical reaction between Mo, in Mo O 3 form, and Zr, in Zr O Cl 2 .8H 2 O form. After the reaction, the gel is filtered, dried and cracked with saline solution. The product is then loaded into glass columns for use as 99m Tc generator. The results showed the good quality of the gel prepared at laboratory level and of the generators evaluated. (author)

  15. Mullite/Mo interfaces formed by Intrusion bonding

    OpenAIRE

    Bartolome, Jose F.; Diaz, Marcos; Moya, Jose S.; Saiz, Eduardo; Tomsia, Antoni P.

    2003-01-01

    The microstructure and strength of Mo/mullite interfaces formed by diffusion bonding at 1650oC has been analyzed. Interfacial metal-ceramic interlocking contributes to flexural strength of approx. 140 MPa as measured by 3 point bending. Saturation of mullite with MoO2 does not affect the interfacial strength.

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

    Indian Academy of Sciences (India)

    SHARIF F ZAMAN

    the influence of acid treated AC as a support with K-Ni-. Mo active ... K-Ni-Mo/AC catalyst was more selective to oxygenates. (>40% ... mineral impurities (K, Si, Sn and Fe) <1%. ...... edge technical support with thanks Science and Technology.

  17. Development of Fission Mo-99 Process for LEU Dispersion Target

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Kon; Lee, Su Seung; Hong, Soon Bog; Jang, Kyung Duk; Park, Ul Jae; Lee, Jun Sig [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    KAERI (Korea Atomic Energy Research Institute) is developing LEU-based fission {sup 99}Mo production process which is connected to the new research reactor (Kijang New Research Reactor, KJRR), which is being constructed in Gijang, Busan, Korea. Historically, the most fission {sup 99}Mo producers have been used highly enriched uranium (HEU) targets so far. However, to reduce the use of HEU in private sector for non-proliferation, {sup 99}Mo producers are forced to convert their HEU-based process to use low enriched uranium (LEU) targets. Economic impact of a target conversion from HEU to LEU is significant. Overall cost for the production of the fission {sup 99}Mo increases significantly with the conversion of fission {sup 99}Mo targets from HEU to LEU. It is not only because the yield of LEU is only 50% of HEU, but also because radioactive waste production increases 200%. On the basis, worldwide efforts on the development of {sup 99}Mo production process that is optimized for the LEU target become an important issue. In this study, fission {sup 99}Mo process with non-irradiated LEU targets was presented except separation and purification steps. Pre- and post-irradiation tests of the fission {sup 99}Mo target will be done in 4th quarter of 2016.

  18. Toroidal deuteron accelerator for Mo-98 neutron activation

    International Nuclear Information System (INIS)

    Araujo, Wagner L.; Campos, Tarcisio P.R. Universidade Federal de Minas Gerais

    2017-01-01

    The radionuclide Tc- 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 13 n.s -1 . In a arrangement of 30 column samples, TTS provides 230 mCi s -1 Mo 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)

  19. Development of Fission Mo-99 Process for LEU Dispersion Target

    International Nuclear Information System (INIS)

    Lee, Seung Kon; Lee, Su Seung; Hong, Soon Bog; Jang, Kyung Duk; Park, Ul Jae; Lee, Jun Sig

    2016-01-01

    KAERI (Korea Atomic Energy Research Institute) is developing LEU-based fission 99 Mo production process which is connected to the new research reactor (Kijang New Research Reactor, KJRR), which is being constructed in Gijang, Busan, Korea. Historically, the most fission 99 Mo producers have been used highly enriched uranium (HEU) targets so far. However, to reduce the use of HEU in private sector for non-proliferation, 99 Mo producers are forced to convert their HEU-based process to use low enriched uranium (LEU) targets. Economic impact of a target conversion from HEU to LEU is significant. Overall cost for the production of the fission 99 Mo increases significantly with the conversion of fission 99 Mo targets from HEU to LEU. It is not only because the yield of LEU is only 50% of HEU, but also because radioactive waste production increases 200%. On the basis, worldwide efforts on the development of 99 Mo production process that is optimized for the LEU target become an important issue. In this study, fission 99 Mo process with non-irradiated LEU targets was presented except separation and purification steps. Pre- and post-irradiation tests of the fission 99 Mo target will be done in 4th quarter of 2016

  20. 77 FR 29875 - Establishment of Class E Airspace; Houston, MO

    Science.gov (United States)

    2012-05-21

    ...-0903; Airspace Docket No. 11-ACE-20] Establishment of Class E Airspace; Houston, MO AGENCY: Federal... at Houston, MO. Controlled airspace is necessary to accommodate new Area Navigation (RNAV) Standard Instrument Approach Procedures at Houston Memorial Airport. The FAA is taking this action to enhance the...

  1. Mo-99 production by fission and future projections

    International Nuclear Information System (INIS)

    Carranza, E.C.; Novello, A.; Bronca, M.; Cestau, D.; Bavaro, R.; Centurion, R.; Bravo, C.; Bronca, P.; Gualda, E.; Fraguas, F.; Giomi, A.; Ivaldi, L.

    2012-01-01

    Description of the I-131 and Mo-99 production process: The process starts with the irradiation of uranium-aluminum mini plates in the RA-3, Argentinean Reactor No.3, Ezeiza Atomic Center. In a nuclear reactor there is a constant flow of neutrons and when a neutron with proper energy impacts on a nucleus of U-235, it is absorbed at the same time generate an unstable configuration nuclear. For this reason, the nucleus formed is fission, getting two different atoms. Approximately 6% of the fissions produce Mo-99 and 3% produce I-131; the percentage remaining corresponds to formation of atoms without interest for use in medicine. In conclusion, the objective of the process developed in the Fission Plant, is starting from uranium mini plates, separate the Mo-99 and I-131 generated, the remaining elements formed. - Evolution of Mo-99 Production in the last 10 years: The Fission Mo-99 Plant Production begins routine production of Mo-99 in 1985, using targets made of uranium enriched at 90% U-235. In the 1990s, global concern regarding the use of highly enriched uranium, due to non-proliferation issues, caused the interruption of supply of nuclear material (HEU enriched at 90% of U-235). Following this, Argentina developed target based on low-enriched uranium (less than 20% U-235), becoming in 2002 the first country in the world to produce Mo-99 with LEU targets. From 2002 to date, the activity produced of Mo-99 has been tripled annually (author)

  2. A review on the process technology for Mo-99 production

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Hoh; Yoo, Jae Hyung; Jung, Won Myung; Lee, Kyoo Il; Woo, Moon Sik; Hwang, Doo Sung; Kim, Yun Koo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1994-07-01

    Tc-99m is most frequently used in nuclear medical diagnostics because of its favourable nuclear properties and reasonable prices, and the demand of Tc-99m, is on the increase recently. Mo-99, the parent radionuclide of Tc-99m, is the only source of Tc-99m. This review described overall aspects of process technologies for Mo-99 production. Firstly, the chemical, physical and radioactive properties of Tc-99m, Mo-99 were examined to understand Mo-99 separation process. Also, the technology for Mo-99 production with both the neutron capture and nuclear fission method were examined. But the neutron capture method was scarcely used for large production of Mo-99 because of its low specific activity and high production cost. This review also described mainly process technologies in the nuclear fission method, fabrication and condition for irradiation of targets, transport and dissolution of targets irradiated, separation and purification of Mo-99, etc. Especially, for Mo-99 separation and purification process, the characteristics, merits and demerits of various processes, which have been developed in a few countries, were examined and analyzed. 30 figs., 16 tabs., 60 refs. (Author).

  3. Highly flexible, conductive and transparent MoO3/Ag/MoO3 multilayer electrode for organic photovoltaic cells

    International Nuclear Information System (INIS)

    Abachi, T.; Cattin, L.; Louarn, G.; Lare, Y.; Bou, A.; Makha, M.; Torchio, P.

    2013-01-01

    MoO 3 /Ag/MoO 3 (MAM) multilayer structures were deposited by vacuum evaporation on polyethylene terephthalate (PET) substrate. We demonstrate that, as in the case of glass substrate, the sheet resistance of such structures depends significantly on the Ag film deposition rate. When it is deposited between 0.2 and 0.4 nm/s, an Ag thickness of 11 nm allows achieving sheet resistance of 13 Ω/sq and an averaged transmission of 74%. A study of the influence of the PET substrate on the optimum MoO 3 thicknesses was done. A good qualitative agreement between the theoretical calculations of the variation of the optical transmittance of the MoO 3 /Ag/MoO 3 structures is obtained. The optimum MAM structures MoO 3 (17.5 nm)/Ag (11 nm)/MoO 3 (35 nm) has a factor of merit F M = 4.21 10 −3 (Ω/sq) −1 . Proven by the scotch test the MAM structures exhibit a good adhesion to the PET substrates. The MAM structures were also submitted to bending tests. For outer bending, the samples exhibit no variation of their resistance value, while for inner bending there is a small increase of the resistance of the MAM structures. However this increasing is smaller than that exhibited by Indium Tin Oxide. When the PET/MAM structures are used as anode in organic photovoltaic cells, it is shown that the need to use thicker Ag films inside the multilayer and to cover the MAM with Au to obtain promising Current density vs Voltage characteristics is due to the heating of the PET substrate during the deposition process. - Highlights: • MoO 3 /Ag/MoO 3 structures deposited on polyethylene terephthalate substrate. • MoO 3 /Ag/MoO 3 structures deposited by vacuum evaporation. • The Ag deposition rate influences the properties of the structures. • The MoO 3 /Ag/MoO 3 optimum structure has a factor of merit F M = 4.21 10 −3 (Ω/sq) −1 . • The MoO 3 /Ag/MoO 3 structures exhibit a high flexibility

  4. 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.)

  5. MoS2 anchored free-standing three dimensional vertical graphene foam based binder-free electrodes for enhanced lithium-ion storage

    International Nuclear Information System (INIS)

    Ouyang, Bo; Wang, Ying; Zhang, Zheng; Rawat, R.S.

    2016-01-01

    The vertical graphene with hierarchical three-dimensional network architecture is a promising substrate for high energy and power density Li-ion battery due to its large surface area, inherent three-dimensional network and excellent ion transport property. Three dimensional vertical graphene (3DVG) is synthesized via plasma enhanced chemical vapor deposition (PECVD) using cost-effective and environment-friendly natural oil of M. alternifolia as precursor. The MoS 2 nanosheets are then anchored on free-standing 3DVG by hydrothermal method to make the binder free MoS 2 @3DVG anode of a Li-ion battery. The MoS 2 @3DVG electrodes deliver an enhanced capacity of 670 mAh g −1 with the capacity retention of 99% after 30 cycles at 100 mA g −1 , much better than that of the reference sample of MoS 2 @3DG (550 mAh g −1 at 100 mA g −1 ) which uses 3D planar graphene. Superior performance of the vertical graphene based electrode is attributed to the unique hierarchical structure and densely packed reactive edges of the as-synthesized 3DVG. The versatility of plasma-assisted natural precursor based vertical graphene as functional nano-structured substrate for MoS 2 , as active material, for advanced energy storage devices is demonstrated.

  6. 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

  7. Hydrothermal Synthesis of MoO2 and Supported MoO2 Cata-lysts for Oxidative Desulfurization of Dibenzothiophene

    Institute of Scientific and Technical Information of China (English)

    Wang Danhong; Zhang Jianyong; Liu Ni; Zhao Xin; Zhang Minghui

    2014-01-01

    A novel method for obtaining spherical MoO2 nanoparticles and SiO2-Al2O3 supported MoO2 by hydrothermal reduction of Mo (VI) species was studied. The obtained MoO2 catalysts show very high catalytic activity in the oxidative desulfurization (ODS) process. The effect of hydrothermal temperature and crystallization temperature on ODS activity was investigated. The ODS activity of supported MoO2 catalysts with various MoO2 contents were also investigated. The mecha-nism for formation of MoO2 involving oxalic acid was proposed.

  8. ¿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.

  9. The Mo/Ta (100) interface

    International Nuclear Information System (INIS)

    Quintanar, C.; Velasco, V.R.; Garcia-Moliner, F.

    1990-12-01

    We have calculated the interface local density of states (ILDOS) formed by the transition metals Mo/Ta using a tight-binding Slater-Koster description and the Green Function matching method together with quickly converging algorithms to compute the transfer matrices. We obtain the surface LDOS as a byproduct. Our result is a useful tool to analyze experimental results and to check models as a function of the value of the tight-binding parameters either of the bulk or at the interface itself. We consider the (100) direction. We compare the interface to the bulk and to the surface and comment on some recently found experimental results for this interface. (author). 17 refs, 2 figs

  10. 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)

  11. Plasmons on the edge of MoS2 nanostructures

    DEFF Research Database (Denmark)

    Andersen, Kirsten; Jacobsen, Karsten Wedel; Thygesen, Kristian Sommer

    2014-01-01

    Using ab initio calculations we predict the existence of one-dimensional (1D), atomically confined plasmons at the edges of a zigzag MoS2 nanoribbon. The strongest plasmon originates from a metallic edge state localized on the sulfur dimers decorating the Mo edge of the ribbon. A detailed analysis...... of the dielectric function reveals that the observed deviations from the ideal 1D plasmon behavior result from single-particle transitions between the metallic edge state and the valence and conduction bands of the MoS2 sheet. The Mo and S edges of the ribbon are clearly distinguishable in calculated spatially...... resolved electron energy loss spectrum owing to the different plasmonic properties of the two edges. The edge plasmons could potentially be utilized for tuning the photocatalytic activity of MoS2 nanoparticles....

  12. Phase transformation in a Ni-Mo-Cr alloy

    International Nuclear Information System (INIS)

    Dymek, S.; Wrobel, M.; Blicharski, M.; Dollar, M.

    2001-01-01

    The paper gives a characteristic of a nickel-based superalloy containing 25 wt.% Mo and 8 wt.% Cr with particular attention to the influence of a thermochemical and heat treatment on phase transformations. The applied heat treatments are comprised of soaking temperature 1100 o C followed by aging at 650 o C at three conditions: conventional aging for 72 hours, prolonged aging for 4000 hours and prolonged aging for 4000 hours followed by cold working and subsequent aging for 1000 hours. The conventional aging led to the formation of lenticular precipitates of the dispersed metastable Ni 2 (Mo,Cr) phase. The aging for 4000 hours brought about coarsening of the ordered domains without changing their crystallographic and ordering characteristics. The plastic deformation preceded the further aging for 1000 hours accelerated the decomposition of the Ni 2 (Mo,Cr) phase on the mixture of the Ni 3 Mo and Ni 4 Mo-based phases. (author)

  13. Fission induced swelling of 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. [Ulsan National Institute of Science and Technology, 50 UNIST-gil, Eonyang-eup, Uljoo-gun, Ulsan 689-798 (Korea, Republic of); Park, J.M. [Korea Atomic Energy Research Institute, 989-111 Daedeok-daero, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Robinson, A.B. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-6188 (United States)

    2015-10-15

    Fission-induced swelling of U–Mo/Al dispersion fuel meat was measured using microscopy images obtained from post-irradiation examination. The data of reduced-size plate-type test samples and rod-type test samples were employed for this work. A model to predict the meat swelling of U–Mo/Al dispersion fuel was developed. This model is composed of several submodels including a model for interaction layer (IL) growth between U–Mo and Al matrix, a model for IL thickness to IL volume conversion, a correlation for the fission-induced swelling of U–Mo alloy particles, a correlation for the fission-induced swelling of IL, and models of U–Mo and Al consumption by IL growth. The model was validated using full-size plate data that were not included in the model development.

  14. Signatures of Low-Mo Ancient Ocean May be Preserved in Cyanobacterial Genomes

    Science.gov (United States)

    Glass, J. B.; Wolfe-Simon, F. L.; Poret-Peterson, A. T.; Anbar, A. D.

    2010-04-01

    Before 800 million years ago, Mo was scarce in the ocean. We present evidence that primitive cyanobacteria store Mo using a protein called "Mop." Mop genes preserved in modern genomes may be signatures of the imprint of ancient Mo limitation.

  15. 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.

  16. Determination of Mo- and Ca-isotope ratios in Ca100MoO4 crystal for AMoRE-I experiment

    Science.gov (United States)

    Karki, S.; Aryal, P.; Kim, H. J.; Kim, Y. D.; Park, H. K.

    2018-01-01

    The first phase of the AMoRE (Advanced Mo-based Rare process Experiment) is to search for neutrinoless double-beta decay of 100Mo with calcium molybdate (Ca100MoO4) crystals enriched in 100Mo and depleted in 48Ca using a cryogenic technique at Yangyang underground laboratory in Korea. It is important to know 100Mo- and 48Ca-isotope ratios in Ca100MoO4 crystal to estimate half-life of 100Mo decays and to 2 νββ background from 48Ca. We employed the ICP-MS (Inductive Coupled Plasma Mass Spectrometer) to measure 100Mo- and 48Ca-isotope ratios in Ca100MoO4 crystal. The measured results for 100Mo- and 48Ca-isotope ratios in the crystal are (94 . 6 ± 2 . 8) % and (0 . 00211 ± 0 . 00006) %, respectively, where errors are included both statistical and systematic uncertainties.

  17. Intercalation of Si between MoS2 layers

    Directory of Open Access Journals (Sweden)

    Rik van Bremen

    2017-09-01

    Full Text Available 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.

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

    International Nuclear Information System (INIS)

    Gotcheva, N.; Macchi, L.; Oedewald, P.; Eitrheim, M.H.R.; Axelsson, C.; Reiman, T.; Pietikaeinen, E.

    2013-04-01

    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)

  19. 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)

  20. Benchmark experiment for the cross section of the 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo reactions

    Science.gov (United States)

    Takács, S.; Ditrói, F.; Aikawa, M.; Haba, H.; Otuka, N.

    2016-05-01

    As nuclear medicine community has shown an increasing interest in accelerator produced 99mTc radionuclide, the possible alternative direct production routes for producing 99mTc were investigated intensively. One of these accelerator production routes is based on the 100Mo(p,2n)99mTc reaction. The cross section of this nuclear reaction was studied by several laboratories earlier but the available data-sets are not in good agreement. For large scale accelerator production of 99mTc based on the 100Mo(p,2n)99mTc reaction, a well-defined excitation function is required to optimise the production process effectively. One of our recent publications pointed out that most of the available experimental excitation functions for the 100Mo(p,2n)99mTc reaction have the same general shape while their amplitudes are different. To confirm the proper amplitude of the excitation function, results of three independent experiments were presented (Takács et al., 2015). In this work we present results of a thick target count rate measurement of the Eγ = 140.5 keV gamma-line from molybdenum irradiated by Ep = 17.9 MeV proton beam, as an integral benchmark experiment, to prove the cross section data reported for the 100Mo(p,2n)99mTc and 100Mo(p,pn)99Mo reactions in Takács et al. (2015).

  1. Carbon and Mo transformations during the synthesis of mesoporous Mo2C/carbon catalysts by carbothermal hydrogen reduction

    Science.gov (United States)

    Wang, Haiyan; Liu, Shida; Liu, Bing; Montes, Vicente; Hill, Josephine M.; Smith, Kevin J.

    2018-02-01

    The synthesis of mesoporous Mo2C/carbon catalysts by carbothermal hydrogen reduction is reported. Petroleum coke (petcoke) was activated with KOH at 800 °C to obtain high surface area microporous activated petcoke (APC; 2000 m2/g). The APC was wet impregnated with ammonium heptamolybdate (AHM: 10 wt% Mo), dried and reduced in H2 at temperatures from 400 to 800 °C, to yield Mo2C/APC catalysts. Increased reduction temperature increased the Mo2C yield and the mesoporous volume of the Mo2C/APC. At a reduction temperature of 750 °C the mesopore volume of the catalyst doubled compared to the APC support and accounted for 37% of the total pore volume. Maintaining the final CHR temperature for 90 min further increased the Mo2C yield and mesoporosity of the catalyst. The role of Mo2C in the catalytic hydrogenation of the APC and mesopore generation is demonstrated. The activity of the Mo2C/carbon catalysts in the hydrodeoxygenation of 4-methyl phenol increased with increased CHR temperature and catalyst mesoporosity.

  2. 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

    2018-01-01

    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.

  3. Coke formation during the hydrotreatment of bio-oil using NiMo and CoMo catalysts

    NARCIS (Netherlands)

    Kadarwati, Sri; Hu, Xun; Gunawan, Richard; Westerhof, Roel; Gholizadeh, Mortaza; Hasan, M. D.Mahmudul; Li, Chun-Zhu

    2017-01-01

    This study aims to investigate the coke formation during the hydrotreatment of bio-oil at low temperature. The catalytic hydrotreatment of bio-oil produced from the pyrolysis of mallee wood was carried out using pre-sulphided NiMo and CoMo catalysts at a temperature range of 150–300 °C. Our results

  4. Effect of Mo addition on the electrocatalytic activity of Pt-Sn-Mo/C for direct ethanol fuel cells

    International Nuclear Information System (INIS)

    Lee, Eungje; Murthy, Arun; Manthiram, Arumugam

    2011-01-01

    Carbon-supported Pt-Sn-Mo electrocatalysts have been synthesized by a polyol reduction method and characterized for ethanol electro-oxidation reaction (EOR). While the percent loading of the synthesized nanoparticles on the carbon support is higher than 35%, energy dispersive spectroscopy (EDS) reveals that the Mo contents in the nanoparticle catalysts are lower than the nominal value, indicating incomplete reduction of the Mo precursor. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses reveal that the Sn and Mo exist as oxide phases at the surface layers of the nanoparticles and the degree of alloying is very low. The electrochemical properties of the electrocatalysts have been evaluated by cyclic voltammetry (CV) and chronoamperometry. The catalytic activity for EOR decreases in the order PtSnMo 0.6 /C > PtSnMo 0.4 /C > PtSn/C. Single cell direct ethanol fuel cell (DEFC) tests also confirm that the PtSnMo 0.6 /C anode catalyst exhibit better performance than the PtSn/C anode catalyst. An analysis of the electrochemical data suggests that the incorporation of Mo to Pt-Sn enhances further the catalytic activity for EOR.

  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. 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

  8. ¿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

  9. Studies of the effect of irradiation in a nuclear reactor, of targets containing Mo used for the preparation of 99Mo gel, material that constitutes the 99Mo - 99mTc generators

    International Nuclear Information System (INIS)

    Nieto, Renata Correa

    2004-01-01

    The most used radioisotope in Nuclear Medicine is 99m Tc, obtained in the 99 Mo - 99m Tc generator form. 99 Mo can be produced by several nuclear reactions in Cyclotron and Reactor. The production in Cyclotron is not technically and commercially feasible. The production in Nuclear Reactor can be made in two ways: 235 U fission and 99 Mo (n,γ) 99 Mo reaction. A project aiming the production of 99 Mo by activation of Mo is under way at IPEN, producing a gel type MoZr generator. There are two ways of preparing the gel and the generators: by irradiating MoO 3 and preparing the gel or by the preparation of the gel and further irradiation. This work consists in the study of the irradiation effects in several targets containing Mo for the production of 99 Mo by the 98 Mo (n,γ) 99 Mo reaction and further preparation of the gel for use as a gel type 99 Mo - 99m Tc generator. Three rinds of gel were studied: zirconium, titanium and cerium molybdate, and their morphology, infrared structure and elution yield of 99m Tc were analysed. The best results were achieved with the generators prepared with MoZr post formed gel, with amorphous structure and better elution yields. The pre formed gel induced crystallinity and worst performance of the generators. (author)

  10. Geochronology of the Thompson Creek Mo Deposit: Evidence for the Formation of Arc-related Mo Deposits

    Science.gov (United States)

    Lawrence, C. D.; Coleman, D. S.; Stein, H. J.

    2016-12-01

    The Thompson Creek Mo deposit in central ID, has been categorized as an arc-related Mo deposit due to the location, grade of Mo, and relative lack of enrichments in F, Rb, and Nb, compared to the Climax-type Mo deposits. Geochronology from this arc-related deposit provides an opportunity to compare and contrast magmatism, and mineralization to that in Climax-type deposits. Distinct pulses of magmatism were required to form the Thompson Creek Mo deposit, which is consistent with recent geochronology from Climax-type deposits. Molybdenite Re-Os geochronology from five veins requires at least three pulses of magmatism and mineralization between 89.39 +/- 0.37 and 88.47 +/- 0.16 Ma. Zircon U-Pb ages from these mineralized samples overlap with molybdenite mineralization, but show a much wider range (91.01 +/- 0.37 to 87.27 +/- 0.69). Previous work from Climax-type Mo deposits suggest a correlation between a super eruption, and the subsequent rapid (<1 Ma) onset, and completion of Mo mineralizing intrusions. The longer life (3-4 Ma) for the Thompson Creek Mo deposit suggests that the mineralizing intrusions for arc-related Mo deposits may not need to have as high [Mo] as the Climax-type deposits. This study also finds a shift in the source of magmatism from the pre- to syn-mineralizing intrusions. Zircons from pre-mineralizing intrusions have much higher (15-60 pg) concentrations of radiogenic Pb than zircons from mineralized intrusions, which all have less than 15 pg, though whole rock [U] are similar.

  11. Designing in-plane heterostructures of quantum spin Hall insulators from first principles: 1T'-MoS2 with adsorbates

    DEFF Research Database (Denmark)

    Olsen, Thomas

    2016-01-01

    opportunity to change the local topology by adsorption of atoms or molecules and thus comprise an ideal platform for designing topological heterostructures. Here we apply first-principles calculations to show that the quantum spin Hall insulator 1T'-MoS2 exhibits a phase transition to a trivial insulator upon....... This is in sharp contrast to topological edge states, which typically exhibit strong dispersion that are sensitive to a particular edge termination. The heterostructure is also suggestive of a simple design of one-dimensional metallic networks in sheets of 1T'-MoS2....

  12. A novel three dimensional semimetallic MoS{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhen-Kun [Beijing Computational Science Research Center, Beijing 100084 (China); Departments of Physics and Electronics, Hengyang Normal University, Hengyang 421008 (China); Zhang, Hui; Liu, Li-Min, E-mail: limin.liu@csrc.ac.cn [Beijing Computational Science Research Center, Beijing 100084 (China); Liu, Hao [Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China); Lau, Woon-Ming [Beijing Computational Science Research Center, Beijing 100084 (China); Chengdu Green Energy and Green Manufacturing Technology R and D Center, Chengdu, Sichuan 610207 (China)

    2014-05-28

    Transition metal dichalcogenides (TMDs) have many potential applications, while the performances of TMDs are generally limited by the less surface active sites and the poor electron transport efficiency. Here, a novel three-dimensional (3D) structure of molybdenum disulfide (MoS{sub 2}) with larger surface area was proposed based on first-principle calculations. 3D layered MoS{sub 2} structure contains the basal surface and joint zone between the different nanoribbons, which is thermodynamically stable at room temperature, as confirmed by first principles molecular dynamics calculations. Compared the two-dimensional layered structures, the 3D MoS{sub 2} not only owns the large surface areas but also can effectively avoid the aggregation. Interestingly, although the basal surface remains the property of the intrinsic semiconductor as the bulk MoS{sub 2}, the joint zone of 3D MoS{sub 2} exhibits semimetallic, which is derived from degenerate 3d orbitals of the Mo atoms. The high stability, large surface area, and high conductivity make 3D MoS{sub 2} have great potentials as high performance catalyst.

  13. Using molybdenum depleted in 95Mo in UMo fuel

    International Nuclear Information System (INIS)

    Bakker, K.; Wijtsma, F.; Bos, A.; Mol, C.; Rakhorst, H.; Bretscher, M.; Hofman, G.; Snelgrove, J.

    2002-01-01

    In recent years significant interest was gained in UMo fuel to be used in Material Test Reactors. This interest was induced by the fact that UMo fuel is mechanically stable, even at high uranium concentrations and high U-burnup. These properties are required in order to use Low Enriched Uranium (LEU) and still be able to achieve high flux and burnup values and, thus, to facilitate the conversion from High Enriched Uranium (HEU) to LEU. Neutronics computations have shown that, although the Mo concentration in UMo fuel is not very high (about 5 - 10w%), the neutron absorption cross sections of natural Mo are sufficiently high to have a considerable negative impact on the reactivity of this UMo fuel. In the present research the neutron absorption cross sections of natural Mo are discussed and the option to reduce the cross section of molybdenum by depleting the Mo in 95 Mo is described. Finally the economic consequences of using Mo depleted in 95 Mo are briefly discussed

  14. Homogenization of compacted blends of Ni and Mo powders

    International Nuclear Information System (INIS)

    Lanam, R.D.; Yeh, F.C.H.; Rovsek, J.E.; Smith, D.W.; Heckel, R.W.

    1975-01-01

    The homogenization behavior of compacted blends of Ni and Mo powders was studied primarily as a function of temperature, mean compact composition, and Mo powder particle size. All compact compositions were in the Ni-rich terminal solid-solution range; temperatures were between 950 and 1200 0 C (in the region of the phase diagram where only the Mo--Ni intermediate phase forms); average Mo particle sizes ranged from 8.4 mu m to 48 mu m. Homogenization was characterized in terms of the rate of decrease of the amounts of the Mo-rich terminal solid-solution phase and the Mo--Ni intermediate phase. The experimental results were compared to predictions based upon the three-phase, concentric-sphere homogenization model. In general, agreement between experimental data and model predictions was fairly good for high-temperature treatments and for compact compositions which were not close to the solubility limit of Mo in Ni. Departures from the model are discussed in terms of surface diffusion contributions to homogenization and non-uniform mixing effects. (U.S.)

  15. 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

  16. Study of methodologies for quality control of 99Mo used in 99Mo/99mTc generators

    International Nuclear Information System (INIS)

    Said, Daphne de Souza

    2016-01-01

    99m Tc is the most used radionuclide in nuclear medicine. In Brazil, the 99 Mo/ 99m Tc generators are exclusively produced by Radiopharmacy Center at IPEN-CNEN/ SP, by importing 99 Mo from different suppliers. 99 Mo (t 1/2 = 66 h) is a fission product of 235 U and it can have radionuclidic impurities that are prejudicial for human health. For safe use of generators, it is necessary to perform the evaluation of 99 Mo by quality control tests in order to assess if 99 Mo complies with the specifications. The European Pharmacopoeia (EP) presents a monograph for evaluation of the quality of the [ 99 Mo] solution as sodium molybdate,that is used as raw material for 99 Mo/ 99m Tc generators production, including specification parameters (identification, radiochemical purity and radionuclidic purity), analysis methods and limits. However, it has been observed difficulties on the execution and implementation of these methods by the generators producers, with a few literature about this subject, probably due to complexity of the proposed methods. In this work, many quality control parameters of 99 Mo described in the EP monograph were evaluated. Separation methods for 99M o from its radionuclidic impurities by solid phase extraction (SPE) and TLC were studied. After SPE separation, the quantification of metals by ICP-OES to evaluate the percentage of retention of Mo and the percentage of recovery of Ru, Te and Sr using different types of cartridges were proposed, replacing radiotracers use. It was observed that the specific type of SPE cartridge recommended by the EP for separation of 99 Mo presented low recoveries for Ru, compared to other available anion exchange SPE cartridges. 99 Mo samples from different worldwide suppliers were analyzed. It was observed that quantification of 103 Ru in 99 Mo samples with decay time higher than 4 weeks is possible. An alternative method for separation of 131 I from 99 Mo showed promising results by TLC. The quantification of beta and

  17. 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)

  18. Excitation functions of the 98Mo+d reactions

    International Nuclear Information System (INIS)

    Zarubin, P.P.; Padalko, V.Yu.; Khrisanfov, Yu.V.; Lebedev, P.P.; Podkopaev, Yu.N.

    The excitation functions of the 98 Mo+d reactions were studied. The energy dependence of (d,p),(d,n) and (d,α) reactions was investigated by the activation analysis. The energies of deuterons in the range (6-12) MeV were determined by means of the aluminium filters. 98 Mo foils with surface densities of 1.02, 0.23 and 0.14 mgxcm -2 with 98 Mo enrichment of 94.1% were used as targets. The gamma spectra were measured by a Ge(Li) detector. The 98 Mo(d,p) 99 Mo reaction excitation function was determined via detection of 739 and 181 keV γ-radiation of 99 Mo (Tsub(1/2)=66.47h); 140 keV γ-radiation of 99 Tc (Tsub(1/2)=6h) was detected for the 98 Mo(d,n) 99 Tc reaction excitation function determination and 460, 568, 1091, 1200 and 1492 keV γ-quanta of 96 Nb (Tsub(1/2)=23.35h) - for the 98 Mo(d,α) 96 Nb reaction. In the excitation function the wide extremum was observed at Esub(d) approximately 10 MeV. The ratio of cross sections σsup(m)(d,n)/σ(d,p) on the 98 Mo target was determined. The ratio σsup(m)(d,n)/σ(d,p) was found to be decreasing function of the deuteron energy. The relative cross sections were determined with an accuracy of +-5%, while for the absolute values of cross sections the accuracy was +-15%

  19. Elasticity, electronic properties and hardness of MoC investigated by first principles calculations

    International Nuclear Information System (INIS)

    Liu, YangZhen; Jiang, YeHua; Feng, Jing; Zhou, Rong

    2013-01-01

    The crystal structure, cohesive energy, formation enthalpy, mechanical anisotropy, electronic properties and hardness of α−MoC, β−MoC and γ−MoC are investigated by the first-principles calculations. The elastic constants and the bulk moduli, shear moduli, Young's moduli are calculated. The Young's modulus values of α−MoC, β−MoC and γ−MoC are 395.6 GPa, 551.2 GPa and 399.5 GPa, respectively. The surface constructions of Young's moduli identify the mechanical anisotropy of molybdenum carbide, and the results show that anisotropy of α−MoC is stronger than others. The electronic structure indicates that the bonding behaviors of MoC are the combinations of covalent and metallic bonds. The hardness of β−MoC is obviously higher than those of α−MoC and γ−MoC

  20. 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

  1. The crisis of 99Mo. Current trends and challenges

    International Nuclear Information System (INIS)

    Leyva, René; Duatti, Adriano

    2016-01-01

    In recent years they have exacerbated the problems with the availability of 99 Mo in the international market for the production of radio isotopic generators 99 Mo / 99 mTc. The main situation is given by the shutdown, maintenance or damage to the nuclear reactors of the reductor plants. The search for solutions, analysis of alternatives and development of new methods for the 99 Mo, the well-known workhorse of nuclear medicine, are addressed in this paper. Are interesting new routes using cyclotrons. Also shown are the steps taken internationally to alleviate the growing demand against a limited supply in production. (author)

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

    International Nuclear Information System (INIS)

    Devaraj, Arun; Jana, Saumyadeep; McInnis, Colleen A.; Lombardo, Nicholas J.; Joshi, Vineet V.; Sweet, Lucas E.; Manandhar, Sandeep; Lavender, Curt A.

    2016-01-01

    During eutectoid transformation of U-10Mo alloy, uniform metastable ? UMo phase is expected to transform to a mixture of ?-U and ?'-U_2Mo phase. The presence of transformation products in final U-10Mo fuel, especially the ? 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 ? phase volume fraction measured by XRD analysis. XRD analysis of U-10Mo aged at 500°C detected only ? phase and no ?' 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 ? phase with close to 0 at% Mo and ? phase with 28-32 at% Mo, and the Mo concentration was highest at the ?/? interface.

  3. U-Mo/Al-Si interaction: Influence of Si concentration

    International Nuclear Information System (INIS)

    Allenou, J.; Palancher, H.; Iltis, X.; Cornen, M.; Tougait, O.; Tucoulou, R.; Welcomme, E.; Martin, Ph.; Valot, C.; Charollais, F.; Anselmet, M.C.; Lemoine, P.

    2010-01-01

    Within the framework of the development of low enriched nuclear fuels for research reactors, U-Mo/Al is the most promising option that has however to be optimised. Indeed at the U-Mo/Al interfaces between U-Mo particles and the Al matrix, an interaction layer grows under irradiation inducing an unacceptable fuel swelling. Adding silicon in limited content into the Al matrix has clearly improved the in-pile fuel behaviour. This breakthrough is attributed to an U-Mo/Al-Si protective layer around U-Mo particles appeared during fuel manufacturing. In this work, the evolution of the microstructure and composition of this protective layer with increasing Si concentrations in the Al matrix has been investigated. Conclusions are based on the characterization at the micrometer scale (X-ray diffraction and energy dispersive spectroscopy) of U-Mo7/Al-Si diffusion couples obtained by thermal annealing at 450 deg. C. Two types of interaction layers have been evidenced depending on the Si content in the Al-Si alloy: the threshold value is found at about 5 wt.% but obviously evolves with temperature. It has been shown that for Si concentrations ranging from 2 to 10 wt.%, the U-Mo7/Al-Si interaction is bi-layered and the Si-rich part is located close to the Al-Si for low Si concentrations (below 5 wt.%) and close to the U-Mo for higher Si concentrations. For Si weight fraction in the Al alloy lower than 5 wt.%, the Si-rich sub-layer (close to Al-Si) consists of U(Al, Si) 3 + UMo 2 Al 20 , when the other sub-layer (close to U-Mo) is silicon free and made of UAl 3 and U 6 Mo 4 Al 43 . For Si weight concentrations above 5 wt.%, the Si-rich part becomes U 3 (Si, Al) 5 + U(Al, Si) 3 (close to U-Mo) and the other sub-layer (close to Al-Si) consists of U(Al, Si) 3 + UMo 2 Al 20 . On the basis of these results and of a literature survey, a scheme is proposed to explain the formation of different types of ILs between U-Mo and Al-Si alloys (i.e. different protective layers).

  4. Atomic layer deposition of a MoS₂ film.

    Science.gov (United States)

    Tan, Lee Kheng; Liu, Bo; Teng, Jing Hua; Guo, Shifeng; Low, Hong Yee; Tan, Hui Ru; Chong, Christy Yuen Tung; Yang, Ren Bin; Loh, Kian Ping

    2014-09-21

    A mono- to multilayer thick MoS₂ film has been grown by using the atomic layer deposition (ALD) technique at 300 °C on a sapphire wafer. ALD provides precise control of the MoS₂ film thickness due to pulsed introduction of the reactants and self-limiting reactions of MoCl₅ and H₂S. A post-deposition annealing of the ALD-deposited monolayer film improves the crystallinity of the film, which is evident from the presence of triangle-shaped crystals that exhibit strong photoluminescence in the visible range.

  5. NMR and XAS Study of Fe-Mo Double Perovskites

    International Nuclear Information System (INIS)

    Zajac, D.A.; Kapusta, C.; Borowiec, M.; Sikora, M.; Marquina, C.; Blasco, J.; Ibarra, M.R.

    2005-01-01

    The results of NMR and XAS measurements of the A 2 FeMoO 6 double perovskites (DP) (A 2 =Sr 2 , SrBa, Ba 2 , Ca 2 ) at the Fe and Mo K edges are reported and the information on the individual site electronic and magnetic properties is analysed. The compounds studied belong to the family of materials exhibiting a high field '' colossal '' magnetoresistance as well as a low field '' giant '' magnetoresistance. Magnetoresistive properties of the compounds arise from their half-metallicity, i.e. only one spin direction being populated in the conduction band, which consists of overlapping spin down 3d Fe, 2p O and 4d Mo electron bands. Within the model, a spin-down electron undergoes a fast hopping through unoccupied oxygen 2p orbitals between Fe 3+ (3d 5 - spin up) and Mo 6+ (4d 0 ) ionic cores. This mechanism implicates an anti-parallel coupling of the Fe and Mo spins and leads to non-integer magnetic moments and a metallic character below TC. The interaction, in analogy with the '' double exchange '' (DE) in manganites, is called '' double exchange-like '' interaction. The superexchange interaction (SE) is also expected to be present, resulting also in an anti-parallel coupling of 3d Fe 3+ and 4d Mo 5+ spins through occupied oxygen 2p orbitals. The insulating character of SE is connected with an increase of the tilt angle of the Fe-O-Mo bond, which is related to a change of the structural tolerance factor f and results in structural distortions. The molybdenum NMR measurements revealed the existence of a non-integer magnetic moment at Mo and Fe, which can be attributed to the DE-like interaction. However, experiments using Moessbauer spectroscopy have shown the existence of two Fe ionisation states - with integer (SE) and non integer (DE) magnetic moments. The 95 Mo and 97 Mo NMR measurements on A 2 FeMoO 6 (A 2 =Sr 2 , SrBa, Ba 2 , Ca 2 ) presented in this work show different values of the Mo hyperfine field and the corresponding magnetic moment. This is attributed

  6. A thermodynamic evaluation of the Ti-Mo-C system

    International Nuclear Information System (INIS)

    Shim, J.H.; Oh, C.S.; Lee, D.N.

    1996-01-01

    A thermodynamic assessment of the Ti-Mo-C system has been made, employing a two-sublattice regular solution model for the solid solution and carbide phases and an ordinary subregular solution model for the liquid phase. A set of thermodynamic parameters describing the Gibbs energy of each individual phase in the Ti-Mo-C as well as the Ti-Mo systems was evaluated from thermochemical and phase equilibria information available in the literature through a computer-aided optimization procedure called the CALPHAD method. The comparison between the calculated and experimental results was made and practically important phase diagrams are also presented

  7. Solid state reactions of MoO3 and Na2MoO4 with (U.85,Ce.15)O2x

    International Nuclear Information System (INIS)

    Dahale, N.D.; Keskar, Meera; Singh Mudher, K.D.; Chawla, K.L.

    1999-01-01

    (U .85 ,Ce .15 )MoO 6-x was prepared by the solid state reactions of (U .85 ,Ce .15 )O 2±x with MoO 3 in air at 600 deg C. Solid state reactions of Na 2 MoO 4 with (U .85 ,Ce .15 )MoO 6.x up to 550 deg C in air led to the formation of Na 2 (U .85 ,Ce .15 )Mo 2 O 10-x and Na 2 (U .85 , Ce .15 ) 2 Mo 3 O 16-x . These compounds were characterised by x-ray and thermal methods. The x-ray powder data of (U .85 , Ce .15 ) MoO 6-x were indexed on monoclinic system whereas, data of Na 2 (U .85 ,Ce .15 ) Mo 2 O 10-x and Na 2 (U .85 ,Ce .15 ) 2 Mo 3 O 16-x were indexed on orthorhombic and monoclinic system respectively. (author)

  8. 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.

  9. 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; Lu, Ang-Yu; Sonawane, Poonam Ashok; Kumar, U. Rajesh; Yadav, Kanchan; Li, Lain-Jong; Chen, Yit Tsong

    2015-01-01

    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.

  10. Study on Mo(V) species, location and adsorbates interactions in MoH-SAPO-34 by employing ESR and electron spin-echo modulation spectroscopies

    International Nuclear Information System (INIS)

    Back, Gern Ho; Jang, Chang Ki; Ru, Chang Kuk; Cho, Young Hwan; So, Hyun Soo; Larry, Keven

    2002-01-01

    A solid-state reaction of MoO 3 with as-synthesized H-SAPO-34 generated paramagnetic Mo(V) species. The dehydration resulted in weak Mo(V) species, and subsequent activation resulted in the formation of Mo(V) species such as Mo(V) 5c and Mo(V) 6c that are characterized by ESR. The data of ESR and ESEM show the oxomolybdenum species, to be (MoO 2 ) + or (MoO) 3+ . The (MoO 2 ) + species seems to be more probable. Since H-SAPO-34 has a low framework negative charge, (MoO) 3+ with a high positive charge can not be easily stabilized. A solution reaction between the solution of silico-molybdic acid and calcined H-SAPO-34 resulted in only MoO + 2 species. A rhombic ESR signal is observed on adsorption of D 2 O, CD 3 OH, CH 3 CH 2 OD and ND 3 . The Location and coordination structure of Mo(V) species has been determined by three-pulse electron spin-echo modulation data and their simulations. After the adsorption of methanol, ethylene, ammonia, and water for MoH-SAPO-34, three molecules, one and one molecule, respectively, are directly coordinated to (MoO 2 ) +

  11. 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.

  12. Electron-impact ionization of Mo+

    International Nuclear Information System (INIS)

    Ludlow, J.A.; Loch, S.D.; Pindzola, M.S.

    2005-01-01

    The electron-impact direct ionization cross section for Mo + is calculated using both nonperturbative close-coupling and perturbative distorted-wave methods. When distorted-wave calculations for 4d 5 →4d 4 direct ionization are added to distorted-wave calculations for 4p→nl excitation-autoionization, the experimental measurements are found to be 60% lower than the theoretical predictions. Inclusion of nonperturbative three-body Coulomb effects, present in time-dependent close-coupling calculations, are found to reduce the distorted-wave 4d 5 →4d 4 direct ionization cross section by 25%. This is by far the largest reduction yet seen when comparing the two methods for direct subshell ionization of an atomic positive ion in the ground state. However, when the close-coupling calculations for 4d 5 →4d 4 direct ionization are added to distorted-wave calculations for 4p→nl excitation-autoionization, the experimental measurements are still 45% lower than the theoretical predictions. Although we further investigate correlation effects in the initial target state and term-dependent potential effects in the ejected electron state in an attempt to understand the small magnitude of the experimental measurements, the discrepancy between theory and experiment remains unexplained

  13. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago Vanderlei; Giannitsarou, Chrysi; Johnson, CR

    2017-01-01

    We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and define a network aggregator that preserves network cohesion.

  14. Controlled synthesis of MoO3 microcrystals by subsequent calcination of hydrothermally grown pyrazine–MoO3 nanorod hybrids and their photodecomposition properties

    International Nuclear Information System (INIS)

    Rajagopal, S.; Nataraj, D.; Khyzhun, O.Y.; Djaoued, Yahia; Robichaud, Jacques; Kim, Chang-Koo

    2013-01-01

    We present our results on successful synthesis of pyrazine–MoO 3 nanorod hybrids by using pyrazine and MoO 3 nanorods. On the first stage, MoO 3 nanorods were grown hydrothermally and, on the second stage, their mixture with pyrazine was again involved in a hydrothermal reaction to produce organic–inorganic hybrids. To understand the growth mechanism of the hybrids we varied time and temperature of the hydrothermal process. Intercalation of pyrazine was confirmed through X-ray diffraction analysis, X-ray photoelectron spectroscopy, X-ray emission spectroscopy, scanning electron microscopy methods. Upon calcinations, pyrazine was deintercalated, i.e. removed from the MoO 3 hybrid system, and the MoO 3 nanorods were found to bind together resulting in formation of MoO 3 microslabs with increased surface area. Photodecomposition performance of the MoO 3 nanorods, pyrazine–MoO 3 hybrids and MoO 3 microcrystals was studied against Procion Red MX-5B textile dye. A high photodecomposition performance was found to decrease when going from MoO 3 nanorods to MoO 3 microcrystal and, further, to pyrazine–MoO 3 hybrids. - Graphical abstract: Display Omitted - Highlights: • High aspect ratio MoO 3 nanorods were prepared through a new hydrothermal method. • Hybrids of pyrazine–MoO 3 were formed by intercalating pyrazine into MoO 3 nanorods. • Intercalation of pyrazine was confirmed in X-ray spectroscopic analysis. • After calcinations, MoO 3 crystal was retained by binding MoO 3 nanorods together. • High photodegradation performance was noticed from MoO 3 nanorods

  15. Effect of Mo2C/(Mo2C + WC) weight ratio on the microstructure and mechanical properties of Ti(C,N)-based cermet tool materials

    International Nuclear Information System (INIS)

    Xu, Qingzhong; Zhao, Jun; Ai, Xing; Qin, Wenzhen; Wang, Dawei; Huang, Weimin

    2015-01-01

    To optimize the Mo 2 C content in Ti(C,N)-based cermet tool materials used for cutting the high-strength steel of 42CrMo (AISI 4140/4142 steel), the cermets with different Mo 2 C/(Mo 2 C + WC) weight ratios were prepared. And the microstructure and mechanical properties of cermets were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and measurements of transverse rupture strength (TRS), Vickers hardness (HV) and fracture toughness (K IC ). The results indicate that the Mo 2 C/(Mo 2 C + WC) ratios have great influences on the microstructure features and mechanical properties of Ti(C,N)-based cermets. When the Mo 2 C/(Mo 2 C + WC) ratio increases, the Ti(C,N) grains become finer with smaller black cores surrounded by thinner rims, and the structure of cermets tends to be more compact with smaller binder mean free path. Owing to the medium grains and moderate rims, the cermets with a Mo 2 C/(Mo 2 C + WC) ratio of 0.4 exhibit better mechanical properties, and can be chosen as the tool material for machining 42CrMo steel due to the lower Mo content. - Highlights: • Mo 2 C/(Mo 2 C + WC) ratios affect microstructure and mechanical properties of cermets. • Grains become fine and structure of cermets tends to be compact with raised Mo 2 C. • The cermets with a Mo 2 C/(Mo 2 C + WC) ratio of 0.4 can be used to machine 42CrMo steel

  16. Measurement of formation cross-section of 99Mo from the 98Mo(n,γ) and 100Mo(n,2n) reactions.

    Science.gov (United States)

    Badwar, Sylvia; Ghosh, Reetuparna; Lawriniang, Bioletty M; Vansola, Vibha; Sheela, Y S; Naik, Haladhara; Naik, Yeshwant; Suryanarayana, Saraswatula V; Jyrwa, Betylda; Ganesan, Srinivasan

    2017-11-01

    The formation cross-section of medical isotope 99 Mo from the 98 Mo(n,γ) reaction at the neutron energy of 0.025eV and from the 100 Mo(n,2n) reaction at the neutron energies of 11.9 and 15.75MeV have been determined by using activation and off-line γ-ray spectrometric technique. The thermal neutron energy of 0.025eV was used from the reactor critical facility at BARC, Mumbai, whereas the average neutron energies of 11.9 and 15.75MeV were generated using 7 Li(p,n) reaction in the Pelletron facility at TIFR, Mumbai. The experimentally determined cross-sections were compared with the evaluated nuclear data libraries of ENDF/B-VII.1, CENDL-3.1, JENDL-4.0 and JEFF-3.2 and are found to be in close agreement. The 100 Mo(n,2n) 99 Mo reaction cross-sections were also calculated theoretically by using TALYS-1.8 and EMPIRE-3.2 computer codes and compared with the experimental data. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Phase equilibria in the Tl2MoO4–R2(MoO43–Zr(MoO42 (R = Al, Cr systems: synthesis, structure and properties of new triple molybdates Tl5RZr(MoO46 and TlRZr0.5(MoO43

    Directory of Open Access Journals (Sweden)

    V. G. Grossman

    2017-12-01

    Full Text Available The Tl2MoO4–R2(MoO43–Zr(MoO42 (R = Al, Cr systems were studied in the subsolidus region using X-ray powder diffraction and differential scanning calorimetric (DSC analysis. Quasi-binary joins were revealed, and triangulation was carried out. New ternary molybdates: Tl5RZr(MoO46 (5:1:2 and TlRZr0.5(MoO43 (1:1:1 (R = Al, Cr were prepared. The unit cell parameters for the new compounds were calculated.

  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. Synthesis and characterization of MoO3 films by acid hydrolysis of K2Mo4O13

    International Nuclear Information System (INIS)

    Hernan, L.; Morales, J.

    1989-01-01

    The behaviour of K 2 Mo 4 O 13 heated under reflux in an acid medium has been studied. A metastable polymorphic MoO 3 phase crystallizing in the hexagonal system was obtained. Lengthy treatment led to the formation of orthorhombic MoO 3 with the (010) planes perfectly oriented parallel to the substrate. SEM images do not support a topotactic mechanism for the successive transformations. The reactions involved probably take place through the polymerization of discrete units formed in the bulk solution

  20. 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...... study the energy required to form sulfur vacancies, which are believed to be the active sites for many hydrotreating reactions. The presence of Co atoms at the edges is shown to lead to a significant lowering of the metal-sulfur binding energy. This imposes an increase in the concentration of active...

  1. 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.

  2. Properties of corrosion resistance in C + Mo multi implanted steel

    International Nuclear Information System (INIS)

    Zhang Tonghe; Wu Yuguang; Wang Xiaoyan

    2001-01-01

    The influence of multi-implantation on the corrosion resistance of H13 steel was studied using multi-sweep cyclic voltammetry. The formation conditions of phases and its effects on corrosion resistance were studied. The mechanism of improvement in corrosion resistance was discussed. The experimental results show that the increase of Mo dose can improve corrosion resistance, however the increase of C dose can enhance pitting corrosion potential. Both effects were obtained using dual-and multi-implantation. The passivation layer consists of the phases of Fe 2 Mo, FeMo, MoC, Fe 5 C 3 and Fe 7 C 3 in dual implantation surface of steel. It can improve corrosion resistance and increase pitting corrosion potential. Multi-implantation can further improve corrosion and pitting corrosion resistance compared with dual implantation

  3. Anisotropy of heat conduction in Mo/Si multilayers

    International Nuclear Information System (INIS)

    Medvedev, V. V.; Yakshin, A. E.; Kruijs, R. W. E. van de; Bijkerk, F.; Yang, J.; Schmidt, A. J.; Zoethout, E.

    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 tensor. While the mechanisms of the cross-plane heat conduction were studied in detail previously, here we focus on the in-plane heat conduction. To analyze the relative contribution of electron transport to the in-plane heat conduction, we applied sheet-resistance measurements. Results of Mo/Si multilayers with variable thickness of the Mo layers indicate that the net in-plane thermal conductivity depends on the microstructure of the Mo layers

  4. 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.

  5. Single crystal magnetisation of UFe10Mo2

    International Nuclear Information System (INIS)

    Estrela, P.; Godinho, M.; Spirlet, J.C.

    1997-01-01

    Magnetisation measurements have been performed for different directions on aligned UFe 10 Mo 2 single crystals. The results confirm a basal plane anisotropy and suggest an important magnetic contribution from the uranium sublattice. (orig.)

  6. Support effects on hydrotreating activity of NiMo catalysts

    International Nuclear Information System (INIS)

    Dominguez-Crespo, M.A.; Arce-Estrada, E.M.; Torres-Huerta, A.M.; Diaz-Garcia, L.; Cortez de la Paz, M.T.

    2007-01-01

    The effect of the gamma alumina particle size on the catalytic activity of NiMoS x catalysts prepared by precipitation method of aluminum acetate at pH = 10 was studied. The structural characterization of the supports was measured by using XRD, pyridine FTIR-TPD and nitrogen physisorption. NiMo catalysts were characterized during the preparation steps (annealing and sulfidation) using transmission electron microscopy (TEM). Hydrogen TPR studies of the NiMo catalysts were also carried out in order to correlate their hydrogenating properties and their catalytic functionality. Catalytic tests were carried out in a pilot plant at 613, 633 and 653 K temperatures. The results showed that the rate constants of hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrodearomatizing (HDA) at 613-653 K decreased in the following order: A > B > C corresponding to the increase of NiMoS particle size associated to these catalysts

  7. 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.

  8. Thermal behavior analysis of U-Mo/Al dispersion fuel

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Ho Jin; Park, Jong Mang; Lee, Yoon Sang; Kim, Chang Kyu [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2004-07-01

    According to the non-proliferation policy under the reduced enrichment for research and test reactors (RERTR) program, low enriched uranium(LEU) fuel such as uranium silicide dispersion fuels are being used in research reactors. Because of a lower enrichment higher uranium density fuels are required for some high performance research reactors. Some uranium alloys with a high uranium density such as U-Mo alloys have been considered as one of the most promising candidates for a dispersion fuel due to the good irradiation performance. An international qualification program to replace the uranium silicide dispersion fuel with U-Mo dispersion fuel is being carried out under the RERTR program. Although U-Mo powders are conventionally supplied by the mechanical comminuting of as-cast U-Mo alloys, KAERI developed a centrifugal atomization method in order to simplify the preparation process and improve the properties. The centrifugally atomized powders have a rapidly solidified gamma uranium structure and a spherical shape. During the in-reactor operation of a dispersion fuel, interdiffusion or chemical reactions between the fuel particles and the matrix occurr. Intermetallic compounds in the form of UAlx are formed as a result of the diffusional reaction. Because the intermetallic compounds are less dense than the combined reactants, the volume of the fuel element increases after the reaction. In addition to the effect on the swelling performance, the reaction layers between the U-Mo and the Al matrix induces a degradation of the thermal properties of the U-Mo/Al dispersion fuels. It is important to investigate the thermal behavior of U-Mo/Al dispersion fuel according to reaction between the fuel particles and the matrix with the burnup and linear power. In this study, a finite element analysis was used for the calculation of the temperature distribution of the U-Mo/Al dispersion fuel with a burnup and linear power. Kinetics data of the reaction layers such as the growth

  9. Thermal behavior analysis of U-Mo/Al dispersion fuel

    International Nuclear Information System (INIS)

    Ryu, Ho Jin; Park, Jong Mang; Lee, Yoon Sang; Kim, Chang Kyu

    2004-01-01

    According to the non-proliferation policy under the reduced enrichment for research and test reactors (RERTR) program, low enriched uranium(LEU) fuel such as uranium silicide dispersion fuels are being used in research reactors. Because of a lower enrichment higher uranium density fuels are required for some high performance research reactors. Some uranium alloys with a high uranium density such as U-Mo alloys have been considered as one of the most promising candidates for a dispersion fuel due to the good irradiation performance. An international qualification program to replace the uranium silicide dispersion fuel with U-Mo dispersion fuel is being carried out under the RERTR program. Although U-Mo powders are conventionally supplied by the mechanical comminuting of as-cast U-Mo alloys, KAERI developed a centrifugal atomization method in order to simplify the preparation process and improve the properties. The centrifugally atomized powders have a rapidly solidified gamma uranium structure and a spherical shape. During the in-reactor operation of a dispersion fuel, interdiffusion or chemical reactions between the fuel particles and the matrix occurr. Intermetallic compounds in the form of UAlx are formed as a result of the diffusional reaction. Because the intermetallic compounds are less dense than the combined reactants, the volume of the fuel element increases after the reaction. In addition to the effect on the swelling performance, the reaction layers between the U-Mo and the Al matrix induces a degradation of the thermal properties of the U-Mo/Al dispersion fuels. It is important to investigate the thermal behavior of U-Mo/Al dispersion fuel according to reaction between the fuel particles and the matrix with the burnup and linear power. In this study, a finite element analysis was used for the calculation of the temperature distribution of the U-Mo/Al dispersion fuel with a burnup and linear power. Kinetics data of the reaction layers such as the growth

  10. Optimal operation for 3 control parameters of Texaco coal-water slurry gasifier with MO-3LM-CDE algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Cuiwen; Zhang, Yakun; Gu, Xingsheng [Ministry of Education, East China Univ. of Science and Technology, Shanghai (China). Key Lab. of Advanced Control and Optimization for Chemical Processes

    2013-07-01

    Optimizing operation parameters for Texaco coal-water slurry gasifier with the consideration of multiple objectives is a complicated nonlinear constrained problem concerning 3 BP neural networks. In this paper, multi-objective 3-layer mixed cultural differential evolution (MO-3LM-CDE) algorithms which comprise of 4 multi-objective strategies and a 3LM-CDE algorithm are firstly presented. Then they are tested in 6 benchmark functions. Finally, the MO-3LM-CDE algorithms are applied to optimize 3 control parameters of the Texaco coal-water slurry gasifier in methanol production of a real-world chemical plant. The simulation results show that multi-objective optimal results are better than the respective single-objective optimal operations.

  11. Thermochemical study of MoS2 oxidation

    International Nuclear Information System (INIS)

    Filimonov, D.S.; Topor, N.D.; Kesler, Ya.A.

    1990-01-01

    Thermochemical studies of oxidation processes of metallic molybdenum, sulfur, molybdenum disulfide under different conditions in microcalorimeter are conducted. Values of thermal effects which are used to calculate standard formation enthalpy of MoS 2 and which correlate well are obtained. Δ f H 0 (MoS 2 ,298.15 K) recommended value constitutes (-223.0±16.7) kJ/mol

  12. Fatigue Properties of Aged Mod. 9Cr-1Mo

    International Nuclear Information System (INIS)

    Kim, Dae Whan; Kim, Sung Ho; Lee, Chan Bock

    2007-01-01

    Ferritic/Martensitic steel has a good mechanical properties and a lower thermal expansion coefficient than austenitic stainless steel. Mechanical property of Mod. 9Cr-1Mo steel is less than austenitic stainless steel at high temperature. High temperature mechanical properties are affected by precipitation for Mod. 9Cr-1Mo. FMS steel is used for long time at high temperature and the effect of aging on mechanical properties is very important. In this study, low cycle fatigue properties with aging were investigated

  13. Quality assurance of Mo-99/Tc-99m radionuclide generators

    Science.gov (United States)

    Uzunov, Nikolay; Yordanova, Galina; Salim, Seniha; Stancheva, Natalya; Mineva, Vanya; Meléndez-Alafort, Laura; Rosato, Antonio

    2018-03-01

    Gamma-ray spectrometry analyses of the radionuclide content of eluate from two Mo-99/Tc-99m radionuclide generators POLTECHNET have been performed. The relative activities of 99Mo 103Ru and 131I radioisotopes with respect to the activity of 99mTc at different time intervals after the primary pertechnetate elution of the generators have been analyzed. The relative activities of the isotopes were determined and compared to the radionuclidic purity requirements for 99mTc.

  14. 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)

  15. 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.

  16. Non-stoichiometry of MoS2 phase prepared by sputtering

    International Nuclear Information System (INIS)

    Ito, T.; Nakajima, K.

    1978-01-01

    The lattice parameters and S/Mo atomic ratio in sputtered MoS 2 films have been examined as a function of sputtering conditions, especially the vacuum pressure in the chamber. It was found that the deposited films had a defect MoS 2 structure ranging from 1.6 to 2 in S/Mo ratio, depending on the pressure. (author)

  17. 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). ?...

  18. Enhancing photoresponsivity using MoTe2-graphene vertical heterostructures

    Science.gov (United States)

    Kuiri, Manabendra; Chakraborty, Biswanath; Paul, Arup; Das, Subhadip; Sood, A. K.; Das, Anindya

    2016-02-01

    MoTe2 with a narrow band-gap of ˜1.1 eV is a promising candidate for optoelectronic applications, especially for the near-infrared photo detection. However, the photo responsivity of few layers MoTe2 is very small (graphene vertical heterostructures have a much larger photo responsivity of ˜20 mA W-1. The trans-conductance measurements with back gate voltage show on-off ratio of the vertical transistor to be ˜(0.5-1) × 105. The rectification nature of the source-drain current with the back gate voltage reveals the presence of a stronger Schottky barrier at the MoTe2-metal contact as compared to the MoTe2-graphene interface. In order to quantify the barrier height, it is essential to measure the work function of a few layers MoTe2, not known so far. We demonstrate a method to determine the work function by measuring the photo-response of the vertical transistor as a function of the Schottky barrier height at the MoTe2-graphene interface tuned by electrolytic top gating.

  19. High temperature interdiffusion and phase equilibria in U-Mo

    International Nuclear Information System (INIS)

    Lundberg, L.B.

    1988-01-01

    Experimental data for interdiffusion and phase equilibria in the U-Mo system have been obtained over the temperature range 1400 to 1525 K as a fallout from compatibility experiments in which UO 2 was decomposed by lithium in closed molybdenum capsules. Composition-position, x-ray diffraction and microstructural data from the interdiffusion zones indicate that the intermediate phase U 2 Mo is found in this temperature range, contrary to the currently accepted equilibrium U-Mo phase diagram. The U-Mo interdiffusion data are in good agreement with published values. Inclusion of the U 2 Mo phase in a theoretical correlation of interdiffusion and phase equilibria data using Darken's equation indicate that high temperature interdiffusion of uranium and molybdenum follows the usual thermodynamic rules. Significant changes in the value of the thermodynamic based Darken factor near the U 2 Mo phase boundary on the high uranium side are indicated from both the new and published interdiffusion data. 9 refs., 10 figs., 3 tabs

  20. 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.

  1. Tunneling in BP-MoS2 heterostructure

    Science.gov (United States)

    Liu, Xiaochi; Qu, Deshun; Kim, Changsik; Ahmed, Faisal; Yoo, Won Jong

    Tunnel field effect transistor (TFET) is considered to be a leading option for achieving SS mV/dec. In this work, black phosphorus (BP) and molybdenum disulfide (MoS2) heterojunction devices are fabricated. We find that thin BP flake and MoS2 form normal p-n junctions, tunneling phenomena can be observed when BP thickness increases to certain level. PEO:CsClO4 is applied on the surface of the device together with a side gate electrode patterned together with source and drain electrodes. The Fermi level of MoS2 on top of BP layer can be modulated by the side gating, and this enables to vary the MoS2-BP tunnel diode property from off-state to on-state. Since tunneling is the working mechanism of MoS2-BP junction, and PEO:CsClO4\\ possesses ultra high dielectric constant and small equivalent oxide thickness (EOT), a low SS of 55 mV/dec is obtained from MoS2-BP TFET. This work was supported by the Global Research Laboratory and Global Frontier R&D Programs at the Center for Hybrid Interface Materials, both funded by the Ministry of Science, ICT & Future Planning via the National Research Foundation of Korea (NRF).

  2. Nuclear structure of 94,95Mo at high spins

    International Nuclear Information System (INIS)

    Kharraja, B.; Ghugre, S.S.; Garg, U.; Janssens, R.V.; Carpenter, M.P.; Crowell, B.; Khoo, T.L.; Lauritsen, T.; Nisius, D.; Reviol, W.; Mueller, W.F.; Riedinger, L.L.; Kaczarowski, R.

    1998-01-01

    The high-spin level structures of 94,95 Mo (N=52,53) have been investigated via the 65 Cu( 36 S, αp2n) 94 Mo and 65 Cu( 36 S, αpn) 95 Mo reactions at 142 MeV. The level schemes have been extended up to spin J∼19ℎ and excitation energies E x ∼12 MeV. Spherical shell-model calculations have been performed and compared with the experimental energy levels. The level structure of 94 Mo exhibits a single-particle nature and the higher-angular-momentum states are dominated by the excitation of a g 9/2 neutron across the N=50 shell gap. The level sequences observed in 95 Mo have been interpreted on the basis of the spherical shell model and weak coupling of a d 5/2 or a g 7/2 neutron to the 94 Mo core. copyright 1998 The American Physical Society

  3. 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 ...

  4. Influence of H2O and H2S on the Composition, Activity, and Stability of Sulfided Mo, CoMo, and NiMo Supported on MgAl2O4 for Hydrodeoxygenation of Ethylene Glycol

    DEFF Research Database (Denmark)

    Dabros, Trine Marie Hartmann; Gaur, Abhijeet; Pintos, Delfina Garcia

    2018-01-01

    In this work, density functional theory (DFT), catalytic activity tests, and in-situ X-ray absorption spectroscopy (XAS) was performed to gain detailed insights into the activity and stability of MoS2, Ni-MoS2, and Co-MoS2 catalysts used for hydrodeoxygenation (HDO) of ethylene glycol upon...

  5. Study of phase separation and crystallization phenomena in soda-lime borosilicate glass enriched in MoO3

    International Nuclear Information System (INIS)

    Magnin, M.

    2009-09-01

    Molybdenum oxide immobilization (MoO 3 , as fission product) is one of the major challenges in the nuclear glass formulation issues for high level waste solutions conditioning since many years, these solutions arising from spent nuclear fuel reprocessing. Phase separation and crystallisation processes may arise in molten glass when the MoO 3 content is higher than its solubility limit that may depend on glass composition. Molybdenum combined with other elements such as alkali and alkaline-earth may form crystalline molybdates, known as 'yellow phases' in nuclear glasses which may decrease the glass durability. In order to confine high level wastes (HLW) such as the fission product solutions arising from the reprocessing of high burn-up UOX-type nuclear spent fuels, a new glass composition (HLW glass) is being optimized. This work is devoted to the study of the origin and the mechanism of phase separation and crystallization phenomena induced by molybdenum oxide incorporation in the HLW glass. From microstructural and structural point of view, the molybdenum oxide behavior was studied in glass compositions belonging to the SiO 2 -B 2 O 3 - Na 2 O-CaO simplified system which constituted basis for the HLW glass formulation. The structural role of molybdenum oxide in borosilicate network explaining the phase separation and crystallization tendency was studied through the coupling of structural ( 95 Mo, 29 Si, 11 B, 23 Na MAS NMR, XRD) and microstructural (SEM, HRTEM) analysis techniques. The determination of phase separation (critical temperature) and crystallization (liquidus temperature) appearance temperatures by in situ viscosimetry and Raman spectroscopy experiments allowed us to propose a transformation scenario during melt cooling. These processes and the nature of the crystalline phases formed (CaMoO 4 , Na 2 MoO 4 ) that depend on the evolution of MoO 3 , CaO and B 2 O 3 contents were correlated with changes of sodium and calcium cations proportions in the

  6. Achieving tunable doping of MoSe2 based devices using GO@MoSe2 heterostructure

    Science.gov (United States)

    Maji, Tuhin Kumar; Tiwary, Krishna Kanhaiya; Karmakar, Debjani

    2017-05-01

    Doping nature of MoSe2, one of the promising Graphene analogous device material, can be tuned by controlling the concentration of functional groups in Graphene oxide (GO)@MoSe2 heterostructure. In this study, by first-principles simulation, we have observed that GO can be used as a carrier injection layer for MoSe2, where n or p type carriers are introduced within MoSe2 layer depending on the type and concentration of functional moieties in it. Both n and p-type Schottky barrier height modulations are investigated for different modeled configurations of the heterostructure. This combinatorial heterostructure can be a promising material for future electronic device application.

  7. Energy dispersive X-ray fluorescence analysis with Bragg polarized Mo radiation. Energiedispersive Roentgenfluoreszenzanalyse mit Bragg-polarisierter Mo Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Gloeckl, H

    1983-01-01

    The aim of introducing energy dispersive analysis into X-ray fluorescence analysis is to suppress background from the Bremsstrahlung spectrum and the characteristic radiation without an undue reduction of the signal. The variant under consideration uses linearly polarization radiation obtained after a Bragg reflection,under delta = 90/sup 0/. In an introductory part, Bragg reflection, fluorescence and strong radiation are considered quantitatively with respect to counting statistics and detection limits. In the experimental part two combinations are describe, of a Ta crystal with a Cr tube and of a Mo crystal with a Mo tube. Details of adjustment, sample preparation and calibration and detection limits are given. The pros and cons of the Ta/Cr and the Mo/Mo are contrasted and proposals for further improvements are given.

  8. Irradiation performance of U-Mo-Ti and U-Mo-Zr dispersion fuels in Al-Si matrixes

    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); Hofman, G.L. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Robinson, A.B.; Wachs, D.M. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-6188 (United States); Ryu, H.J.; Park, J.M.; Yang, J.H. [Korea Atomic Energy Research Institute, 150 Deokjin-dong, Yuseong-gu, Daejeon 305-353 (Korea, Republic of)

    2012-08-15

    Performance of U-7 wt.%Mo with 1 wt.%Ti, 1 wt.%Zr or 2 wt.%Zr, dispersed in an Al-5 wt.%Si alloy matrix, was investigated through irradiation tests in the ATR at INL and HANARO at KAERI. Post-irradiation metallographic features show that the addition of Ti or Zr suppresses interaction layer growth between the U-Mo and the Al-5 wt.%Si matrix. However, higher fission gas swelling was observed in the fuel with Zr addition, while no discernable effect was found in the fuel with Ti addition as compared to U-Mo without the addition. Known to have a destabilizing effect on the {gamma}-phase U-Mo, Zr, either as alloy addition or fission product, is ascribed for the disadvantageous result. Considering its benign effect on fuel swelling, with slight disadvantage from neutron economy point of view, Ti may be a better choice for this purpose.

  9. 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.

  10. Kinetics of the U-1% Mo alloy transformation during continual cooling; Kinetika transformacije legura U-1% Mo pri kontinuiranom hladjenju

    Energy Technology Data Exchange (ETDEWEB)

    Mihajlovic, A; Djuric, B; Tepavac, P [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Yugoslavia)

    1965-11-15

    Study of continuous cooling of the U-1% Mo alloy is significant if it could be used as fuel in the nuclear reactor. Previous studies were dealing with relatively low cooling rate up to 3 deg C/s{sup 1}, which produced alpha + gamma structure. This task was devoted to testing the U-1% Mo alloy properties at higher cooling rates in order to discover whether bainite reaction and favourable alpha grain could be achieved under certain conditions.

  11. Real-time Human Activity Recognition using a Body Sensor Network

    DEFF Research Database (Denmark)

    Wang, Liang; Gu, Tao; Chen, Hanhua

    2010-01-01

    Real-time activity recognition using body sensor networks is an important and challenging task and it has many potential applications. In this paper, we propose a realtime, hierarchical model to recognize both simple gestures and complex activities using a wireless body sensor network. In this mo...

  12. 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.

  13. Measurements of emissivities on JT-60 first wall materials (inconel 625, Mo, TiC-coated Mo)

    International Nuclear Information System (INIS)

    Nakamura, Hiroo; Shimizu, Masatsugu; Makino, Toshiro; Kunitomo, Takeshi.

    1985-02-01

    To evaluate heat removal performance of JT-60 first wall, emissivities and reflectivities on Inconel 625, Mo, TiC coated Mo with optically smooth surface and actual surface are measured at temperature from a room temperature to 1300 K. Spectra are measured in the rnage of wave lengthes from 0.34 μm to 20 μm. Actual surfaces are machined/pickled surfaces for Inconel 625, electro-polished surfaces for molybdenum, and as-coated surfaces for TiC-coated molybdenum. Results of Inconel 625 and molybdenum with oplically smooth surfaces are examined by a two-electrons-type dispersion model of optical constants. Electronic constants of the equation are given and formulated in order to correlates the macroscopic properties of the radiative heat transfer. Total emissivities, obtained from the spectral emissivities of optically smooth surface, are 0.13(RT) -- 0.21(1300 K) for Inconel 625, 0.035(RT) -- 0.18(1300 K) for Mo, and 0.053(RT) for TiC-coated Mo. Moreover, total emissivities of the actual surface at a room temperature are 0.35(Inconel 625), 0.124(Mo), and 0.073(TiC-coated Mo). Large dependence of the emissivities on temperature and wave length shows that the model including these dependences is necessary for an accurate evaluation of the radiative heat transfer. (author)

  14. Interface morphology of Mo/Si multilayer systems with varying Mo layer thickness studied by EUV diffuse scattering.

    Science.gov (United States)

    Haase, Anton; Soltwisch, Victor; Braun, Stefan; Laubis, Christian; Scholze, Frank

    2017-06-26

    We investigate the influence of the Mo-layer thickness on the EUV reflectance of Mo/Si mirrors with a set of unpolished and interface-polished Mo/Si/C multilayer mirrors. The Mo-layer thickness is varied in the range from 1.7 nm to 3.05 nm. We use a novel combination of specular and diffuse intensity measurements to determine the interface roughness throughout the multilayer stack and do not rely on scanning probe measurements at the surface only. The combination of EUV and X-ray reflectivity measurements and near-normal incidence EUV diffuse scattering allows to reconstruct the Mo layer thicknesses and to determine the interface roughness power spectral density. The data analysis is conducted by applying a matrix method for the specular reflection and the distorted-wave Born approximation for diffuse scattering. We introduce the Markov-chain Monte Carlo method into the field in order to determine the respective confidence intervals for all reconstructed parameters. We unambiguously detect a threshold thickness for Mo in both sample sets where the specular reflectance goes through a local minimum correlated with a distinct increase in diffuse scatter. We attribute that to the known appearance of an amorphous-to-crystallization transition at a certain thickness threshold which is altered in our sample system by the polishing.

  15. Controllable Growth of Monolayer MoS2 and MoSe2 Crystals Using Three-temperature-zone Furnace

    Science.gov (United States)

    Zheng, Binjie; Chen, Yuanfu

    2017-12-01

    Monolayer molybdenum disulfide (MoS2) and molybdenum diselenide (MoSe2) have attracted a great attention for their exceptional electronic and optoelectronic properties among the two dimensional family. However, controllable synthesis of monolayer crystals with high quality needs to be improved urgently. Here we demonstrate a chemical vapor deposition (CVD) growth of monolayer MoS2 and MoSe2 crystals using three-temperature-zone furnace. Systematical study of the effects of growth pressure, temperature and time on the thickness, morphology and grain size of crystals shows the good controllability. The photoluminescence (PL) characterizations indicate that the as-grown monolayer MoS2 and MoSe2 crystals possess excellent optical qualities with very small full-width-half-maximum (FWHM) of 96 me V and 57 me V, respectively. It is comparable to that of exfoliated monolayers and reveals their high crystal quality. It is promising that our strategy should be applicable for the growth of other transition metal dichalcogenides (TMDs) monolayer crystals.

  16. Room-temperature superparamagnetism due to giant magnetic anisotropy in Mo S defected single-layer MoS2

    Science.gov (United States)

    Khan, M. A.; Leuenberger, Michael N.

    2018-04-01

    Room-temperature superparamagnetism due to a large magnetic anisotropy energy (MAE) of a single atom magnet has always been a prerequisite for nanoscale magnetic devices. Realization of two dimensional (2D) materials such as single-layer (SL) MoS2, has provided new platforms for exploring magnetic effects, which is important for both fundamental research and for industrial applications. Here, we use density functional theory (DFT) to show that the antisite defect (Mo S ) in SL MoS2 is magnetic in nature with a magnetic moment μ of  ∼2 μB and, remarkably, exhibits an exceptionally large atomic scale MAE =\\varepsilon\\parallel-\\varepsilon\\perp of  ∼500 meV. Our calculations reveal that this giant anisotropy is the joint effect of strong crystal field and significant spin–orbit coupling (SOC). In addition, the magnetic moment μ can be tuned between 1 μB and 3 μB by varying the Fermi energy \\varepsilonF , which can be achieved either by changing the gate voltage or by chemical doping. We also show that MAE can be raised to  ∼1 eV with n-type doping of the MoS2:Mo S sample. Our systematic investigations deepen our understanding of spin-related phenomena in SL MoS2 and could provide a route to nanoscale spintronic devices.

  17. A modified {sup 99} Mo- {sup 99} Tc generator on Zirconium molybdo- phosphate-{sup 99} Mo gel. Vol. 3

    Energy Technology Data Exchange (ETDEWEB)

    El-Kolaly, M T; Talaat, H [Labelled Compounds Department, Cairo (Egypt); Botros, N [Radioistspe and Generator Department, Radioisotope Production and Sealed Source Division, Hot Laboratories Center, Atomic Energy Authority, Cairo (Egypt)

    1996-03-01

    A modified {sup 99} Mo - {sup 99} Tc gel generator is described. The new generator is based on the use of zirconium molybdophosphate - {sup 99} Mo gel in which {sup 99} Mo chemically combined in the gel structure, where {sup 99m}Tc can be easily eluted with distilled water or saline. The gel was prepared via chemical reaction between zirconyl chloride and molybdophosphate - {sup 99} Mo solution. The PH of the reaction mixture was adjusted with NaOH. Different gels have been prepared by varying the molar ratio of Mo:Zr:p. The PH and time of digeston on complete gel formation was also investigated in order to optimize the condition of gel preparation. Molybdophosphate {sup 32} P solution was used to determine the phosphorous content in the gel and in the {sup 99m}Tc eluate. The temperature and time of drying of the gel and their effect on {sup 99m}Tc elution efficiency were also studied. From the data obtained, the optimum conditions for routine production of {sup 99} Mo - {sup 99m}Tc generator are presented and discussed. 2 figs., 6 tabs.

  18. 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.

  19. Separation and purification of 99Mo from uranium and fission products using Cintichem process, our experience

    International Nuclear Information System (INIS)

    Manolkar, R.B.; Mathakar, A.R.; Kumar, Yogendra; Kumar, Manoj; Dash, A.; Venkatesh, Meera; Pillai, K.T.; Singh, Sarbjit; Venugopal, V.

    2009-01-01

    A pilot study was carried out to assess the feasibility of producing 99 Mo by fission of Unat following the Cintichem method. U-Mo alloy was irradiated for one week at Dhruva reactor and processed for the separation of 99 Mo from fission products. The irradiated targets were chemically processed to separate and purify the 99 Mo. Recovery of ∼70% and the purity of 99 Mo was > 99%. (author)

  20. 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.

  1. 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

  2. Combining ChIP-chip and expression profiling to model the MoCRZ1 mediated circuit for Ca/calcineurin signaling in the rice blast fungus.

    Directory of Open Access Journals (Sweden)

    Soonok Kim

    2010-05-01

    Full Text Available Significant progress has been made in defining the central signaling networks in many organisms, but collectively we know little about the downstream targets of these networks and the genes they regulate. To reconstruct the regulatory circuit of calcineurin signal transduction via MoCRZ1, a Magnaporthe oryzae C2H2 transcription factor activated by calcineurin dephosphorylation, we used a combined approach of chromatin immunoprecipitation - chip (ChIP-chip, coupled with microarray expression studies. One hundred forty genes were identified as being both a direct target of MoCRZ1 and having expression concurrently differentially regulated in a calcium/calcineurin/MoCRZ1 dependent manner. Highly represented were genes involved in calcium signaling, small molecule transport, ion homeostasis, cell wall synthesis/maintenance, and fungal virulence. Of particular note, genes involved in vesicle mediated secretion necessary for establishing host associations, were also found. MoCRZ1 itself was a target, suggesting a previously unreported autoregulation control point. The data also implicated a previously unreported feedback regulation mechanism of calcineurin activity. We propose that calcium/calcineurin regulated signal transduction circuits controlling development and pathogenicity manifest through multiple layers of regulation. We present results from the ChIP-chip and expression analysis along with a refined model of calcium/calcineurin signaling in this important plant pathogen.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

    Scientists increasingly witness the applications of MoS 2 and MoO 2 in the field of energy conversion and energy storage. On the one hand, MoS 2 and MoO 2 have been widely utilized as promising catalysts for electrocatalytic or photocatalytic hydrogen evolution in aqueous solution. On the other hand, MoS 2 and MoO 2 have also been verified as efficient electrode material for lithium ion batteries. In this review, the synthesis, structure and properties of MoS 2 and MoO 2 are briefly summarized according to their applications for H 2 generation and lithium ion batteries. Firstly, we overview the recent advancements in the morphology control of MoS 2 and MoO 2 and their applications as electrocatalysts for hydrogen evolution reactions. Secondly, we focus on the photo-induced water splitting for H 2 generation, in which MoS 2 acts as an important co-catalyst when combined with other semiconductor catalysts. The newly reported research results of the significant functions of MoS 2 nanocomposites in photo-induced water splitting are presented. Thirdly, we introduce the advantages of MoS 2 and MoO 2 for their enhanced cyclic performance and high capacity as electrode materials of lithium ion batteries. Recent key achievements in MoS 2 - and MoO 2 -based lithium ion batteries are highlighted. Finally, we discuss the future scope and the important challenges emerging from these fascinating materials. (review)

  4. XPS study of organic/MoO3 hybrid thin films for aldehyde gas sensors. Correlation between average Mo valance and sensitivity

    International Nuclear Information System (INIS)

    Itoh, Toshio; Matsubara, Ichiro; Shin, Woosuck; Izu, Noriya; Nishibori, Maiko

    2010-01-01

    We investigate the formaldehyde gas sensing properties of poly(5,6,7,8-tetrahydro-1-naphthylamine)-intercalated MoO 3 thin films ((PTHNA) x MoO 3 ). The resistance responses of (PTHNA) x MoO 3 to formaldehyde increase with increasing intercalation temperature. X-ray photoelectron spectroscopy reveals that the molar ratio of Mo 5+ decreases with increasing intercalation temperature. (author)

  5. 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.

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

    International Nuclear Information System (INIS)

    Barucca, G.; Santecchia, E.; Majni, G.; Girardin, E.; Bassoli, E.; Denti, L.; Gatto, A.; Iuliano, L.; Moskalewicz, T.; Mengucci, P.

    2015-01-01

    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} 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

  7. 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.

  8. Temporal networks

    CERN Document Server

    Saramäki, Jari

    2013-01-01

    The concept of temporal networks is an extension of complex networks as a modeling framework to include information on when interactions between nodes happen. Many studies of the last decade examine how the static network structure affect dynamic systems on the network. In this traditional approach  the temporal aspects are pre-encoded in the dynamic system model. Temporal-network methods, on the other hand, lift the temporal information from the level of system dynamics to the mathematical representation of the contact network itself. This framework becomes particularly useful for cases where there is a lot of structure and heterogeneity both in the timings of interaction events and the network topology. The advantage compared to common static network approaches is the ability to design more accurate models in order to explain and predict large-scale dynamic phenomena (such as, e.g., epidemic outbreaks and other spreading phenomena). On the other hand, temporal network methods are mathematically and concept...

  9. 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.

  10. Phase relations in the systems M2MoO4-Cr2(MoO4)3-Zr(MoO4)2 (M=Li, Na, or Rb)

    International Nuclear Information System (INIS)

    Bazarov, B.G.; Chimitova, O.D.; Bazarova, Ts.T.; Arkhincheeva, S.I.; Bazarova, Zh.G.

    2008-01-01

    Phase equilibria in the systems M 2 MoO 4 -Cr 2 (MoO 4 ) 3 -Zr(MoO 4 ) 2 (M=Li, Na, or Rb) were investigated by X-ray powder diffraction analysis, DTA, and IR spectroscopy. The subsolidus structure of the phase diagrams of the systems under study was established. Two phases are formed in the Rb 2 MoO 4 -Cr 2 (MoO 4 ) 3 -Zr(MoO 4 ) 2 system with the molar ratios of the starting components equal to 5:1:1 (S 2 ) and 1:1:1 (S 1 ). Proceeding from isostructural character of Rb 5 FeHf(MoO 4 ) 6 and S 2 , the unit cell parameters are determined for S 2 [ru

  11. Interaction of Al with O2 exposed Mo2BC

    International Nuclear Information System (INIS)

    Bolvardi, Hamid; Music, Denis; Schneider, Jochen M.

    2015-01-01

    Highlights: • Al adheres to many surfaces. • Solid–solid interactions challenging for real (oxidized) surfaces. • Dissociative O 2 adsorption on Mo 2 BC(0 4 0). • Al nonamer is disrupted on oxidized Mo 2 BC(0 4 0). • Adhesion of a residual Al on the native oxide. - Abstract: A Mo 2 BC(0 4 0) surface was exposed to O 2 . The gas interaction was investigated using ab initio molecular dynamics and X-ray photoelectron spectroscopy (XPS) of air exposed surfaces. The calculations suggest that the most dominating physical mechanism is dissociative O 2 adsorption whereby Mo−O, O−Mo−O and Mo 2 −C−O bond formation is observed. To validate these results, Mo 2 BC thin films were synthesized utilizing high power pulsed magnetron sputtering and air exposed surfaces were probed by XPS. MoO 2 and MoO 3 bond formation is observed and is consistent with here obtained ab initio data. Additionally, the interfacial interactions of O 2 exposed Mo 2 BC(0 4 0) surface with an Al nonamer is studied with ab initio molecular dynamics to describe on the atomic scale the interaction between this surface and Al to mimic the interface present during cold forming processes of Al based alloys. The Al nonamer was disrupted and Al forms chemical bonds with oxygen contained in the O 2 exposed Mo 2 BC(0 4 0) surface. Based on the comparison of here calculated adsorption energy with literature data, Al−Al bonds are shown to be significantly weaker than the Al−O bonds formed across the interface. Hence, Al−Al bond rupture is expected for a mechanically loaded interface. Therefore the adhesion of a residual Al on the native oxide layer is predicted. This is consistent with experimental observations. The data presented here may also be relevant for other oxygen containing surfaces in a contact with Al or Al based alloys for example during forming operations

  12. Resonant photoelectron spectroscopy at the Mo 4p→4d absorption edge in MoS2

    International Nuclear Information System (INIS)

    Lince, J.R.; Didziulis, S.V.; Yarmoff, J.A.

    1991-01-01

    A systematic study has been conducted of the resonant behavior of the valence-band photoelectron spectrum of MoS 2 for hν=26--70 eV, spanning the Mo 4p→4d transition region. A broad Fano-like resonance appears at ∼42 eV in the constant-initial-state (CIS) intensity plot of the d z 2 peak near the valence-band maximum [∼2 eV binding energy (BE)], confirming its predominantly Mo 4d character. A second shoulder on the higher-hν side of the maximum in the d z 2 CIS intensity plot is suggested to result from transitions to unoccupied states in the 5sp band ∼10 eV above E F , by comparison with a partial-yield spectrum and previous inverse-photoemission data. The region of the valence band in the range 3--4.5-eV BE also exhibits resonant behavior, indicating Mo 4d character, although somewhat less than for the d z 2 peak. The 5--7-eV BE range does not exhibit resonance behavior at the Mo 4p edge and, therefore, contains negligible Mo 4d character. A feature at ∼30 eV in the CIS intensity plot for the 5--7-eV BE range could not be definitively assigned in this study, but may be due to a resonance between direct photoemission and a process involving absorption and autoionization of electronic states that contain Mo 5s and 5p character

  13. Electrical characteristics of multilayer MoS2 FET's with MoS2/graphene heterojunction contacts.

    Science.gov (United States)

    Kwak, Joon Young; Hwang, Jeonghyun; Calderon, Brian; Alsalman, Hussain; Munoz, Nini; Schutter, Brian; Spencer, Michael G

    2014-08-13

    The electrical properties of multilayer MoS2/graphene heterojunction transistors are investigated. Temperature-dependent I-V measurements indicate the concentration of unintentional donors in exfoliated MoS2 to be 3.57 × 10(11) cm(-2), while the ionized donor concentration is determined as 3.61 × 10(10) cm(-2). The temperature-dependent measurements also reveal two dominant donor levels, one at 0.27 eV below the conduction band and another located at 0.05 eV below the conduction band. The I-V characteristics are asymmetric with drain bias voltage and dependent on the junction used for the source or drain contact. I-V characteristics of the device are consistent with a long channel one-dimensional field-effect transistor model with Schottky contact. Utilizing devices, which have both graphene/MoS2 and Ti/MoS2 contacts, the Schottky barrier heights of both interfaces are measured. The charge transport mechanism in both junctions was determined to be either thermionic-field emission or field emission depending on bias voltage and temperature. On the basis of a thermionic field emission model, the barrier height at the graphene/MoS2 interface was determined to be 0.23 eV, while the barrier height at the Ti/MoS2 interface was 0.40 eV. The value of Ti/MoS2 barrier is higher than previously reported values, which did not include the effects of thermionic field emission.

  14. Cyclic tensile response of Mo-27 at% Re and Mo-0.3 at% Si solid solution alloys

    Energy Technology Data Exchange (ETDEWEB)

    Yu, X.J.; Kumar, K.S., E-mail: Sharvan_Kumar@brown.edu

    2016-10-31

    Stress-controlled uniaxial cyclic tensile tests were conducted on binary Mo-27 at% Re and Mo-0.3 at% Si solid solutions as a function of temperature and compared against the previously reported cyclic response of pure Mo. The Mo-27 at% Re alloy with a recrystallized grain size of ~30 µm was evaluated in the temperature range 25 °C–800 °C at R=0.1 and stress range that was 80% of the ultimate tensile strength (UTS); a peak in fatigue life was observed between 300 °C and 500 °C. The decrease in fatigue life at the higher temperatures of 700 °C and 800 °C is attributed to dynamic strain aging. Transmission electron microscopy of the cyclically-deformed alloy revealed parallel bands of dislocation at room temperature that transitioned to a uniform cell structure at 500 °C and back to orthogonal planar arrays at 800 °C. The as-extruded Mo-0.3 at% Si alloy was evaluated from 25 °C to 1200 °C and showed superior fatigue life and ratcheting strain resistance as compared to pure Mo and the Mo-27 at% Re alloy (within the temperature range where data were available for comparison). The superior resistance is attributed to the high density of dislocations within the material in this mostly unrecrystallized state rather than Si in solid solution. Above 800 °C, the ratcheting strain increases and fatigue life decreases rapidly with increasing temperature and is associated with dynamic recovery.

  15. On-stack two-dimensional conversion of MoS2 into MoO3

    Science.gov (United States)

    Yeoung Ko, Taeg; Jeong, Areum; Kim, Wontaek; Lee, Jinhwan; Kim, Youngchan; Lee, Jung Eun; Ryu, Gyeong Hee; Park, Kwanghee; Kim, Dogyeong; Lee, Zonghoon; Lee, Min Hyung; Lee, Changgu; Ryu, Sunmin

    2017-03-01

    Chemical transformation of existing two-dimensional (2D) materials can be crucial in further expanding the 2D crystal palette required to realize various functional heterostructures. In this work, we demonstrate a 2D ‘on-stack’ chemical conversion of single-layer crystalline MoS2 into MoO3 with a precise layer control that enables truly 2D MoO3 and MoO3/MoS2 heterostructures. To minimize perturbation of the 2D morphology, a nonthermal oxidation using O2 plasma was employed. The early stage of the reaction was characterized by a defect-induced Raman peak, drastic quenching of photoluminescence (PL) signals and sub-nm protrusions in atomic force microscopy images. As the reaction proceeded from the uppermost layer to the buried layers, PL and optical second harmonic generation signals showed characteristic modulations revealing a layer-by-layer conversion. The plasma-generated 2D oxides, confirmed as MoO3 by x-ray photoelectron spectroscopy, were found to be amorphous but extremely flat with a surface roughness of 0.18 nm, comparable to that of 1L MoS2. The rate of oxidation quantified by Raman spectroscopy decreased very rapidly for buried sulfide layers due to protection by the surface 2D oxides, exhibiting a pseudo-self-limiting behavior. As exemplified in this work, various on-stack chemical transformations can be applied to other 2D materials in forming otherwise unobtainable materials and complex heterostructures, thus expanding the palette of 2D material building blocks.

  16. 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

  17. Preparation and characterization of sintered Mo-Re alloys

    International Nuclear Information System (INIS)

    Morito, F.

    1993-01-01

    By the method of powder metallurgy, we have tried to fabricate Mo-Re alloys, which were electron beam weldable. Severe quality control was carried out during the whole fabrication process focused to reducing oxygen contamination. It is inevitable that the starting raw powders of Mo and Re were both high purity with 99.99 mass% up. Moreover, high vacuum sintering was performed before final sintering with high-purity hydrogen gas. As a result, we obtained electron beam weldable Mo-Re alloys, the total oxygen content of which was about 10 mass ppm or less, respectively. Several specimens were melted by electron beam welding (EBW) method. It was found that EBW gives an easy and effective survey to examine the weldability and the quality of the materials. Fracture surfaces examined by AES exhibited very low content of oxygen, carbon and nitrogen or that less than detectability limit. In conclusion, we have succeeded to obtain defect-free welds of sintered Mo-Re alloys. Furthermore it was found that Mo-Re alloys showed excellent potentialities not only in mechanical properties at low temperature but also in the respects of microstructure. (orig.)

  18. Atomic oxygen-MoS sub 2 chemical interactions

    Energy Technology Data Exchange (ETDEWEB)

    Cross, J.B.; Martin, J.A. (Los Alamos National Lab., NM (USA)); Pope, L.E. (Sandia National Labs., Albuquerque, NM (USA)); Koontz, S.L. (National Aeronautics and Space Administration, Johnson Space Center, Houston, TX (USA))

    1990-10-01

    The present study shows that an O-atom translation energy of 1.5 eV, SO{sub 2} is generated and outgases from an anhydrous MoS{sub 2} surface with an initial reactivity nearly 50% that of kapton. The reaction of atomic oxygen with MoS{sub 2} has little or no translational energy barrier, i.e. thermally generated atomic oxygen reacts as readily as that having 1.5 eV of translational energy. For MoS{sub 2} films sputter-deposited at 50-70deg C, friction measurements showed a high initial friction coefficient (up to 0.25) for MoS{sub 2} surfaces exposed to atomic oxygen, which dropped to the normal low values after several cycles of operation in air and ultrahigh vacuum. For MoS{sub 2} films deposited at 200deg C, the friction coefficient was not affected by the O-atom exposure. (orig.).

  19. Proton-fission for the accelerator production of Mo-99

    International Nuclear Information System (INIS)

    Lagunas-Solar, M.C.; Jungerman, J.A.; Castaneda, C.M.

    1993-01-01

    The production of Mo-99 (66.0 h) via de U-238(p,f) Mo-99 fission reaction is proposed as a non-reactor source of this essential precursor of 6.6-h Tc-99m, an isotope of wide use of diagnostic nuclear medicine applications. Measurements of the total excitation function for the U-238(p,f) reaction indicated a maximum and fairly constant cross section of 1.4 barns at > 30 MeV. Combining the advances of high-current (mA) H-accelerators with dual beam (dual target) operation, and assuming a 5% fission yield, estimates of Mo-99 reaches 5 to 14 Ci/h at 1 mA. The proton fission production of Mo-99 appears to more advantageous than the reactor produced via evaporation neutron-induced fission. An accelerator method could allow securing ample supply of Mo-99 independently of the current scarce reactor operation, while also simplifying the associated waste management problems as well as some of the environmental concerns

  20. Nonlinear optical characteristics of monolayer MoSe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Le, Chinh Tam; Ullah, Farman; Senthilkumar, Velusamy; Kim, Yong Soo [Department of Physics and Energy Harvest Storage Research Center, University of Ulsan (Korea, Republic of); Clark, Daniel J.; Jang, Joon I. [Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, NY (United States); Sim, Yumin; Seong, Maeng-Je [Department of Physics, Chung-Ang University, Seoul (Korea, Republic of); Chung, Koo-Hyun [School of Mechanical Engineering, University of Ulsan (Korea, Republic of); Park, Hyoyeol [Electronics, Communication and Semiconductor Applications Department, Ulsan College (Korea, Republic of)

    2016-08-15

    In this study, we utilized picosecond pulses from an Nd:YAG laser to investigate the nonlinear optical characteristics of monolayer MoSe{sub 2}. Two-step growth involving the selenization of pulsed-laser-deposited MoO{sub 3} film was employed to yield the MoSe{sub 2} monolayer on a SiO{sub 2}/Si substrate. Raman scattering, photoluminescence (PL) spectroscopy, and atomic force microscopy verified the high optical quality of the monolayer. The second-order susceptibility χ{sup (2)} was calculated to be ∝50 pm V{sup -1} at the second harmonic wavelength λ{sub SHG} ∝810 nm, which is near the optical gap of the monolayer. Interestingly, our wavelength-dependent second harmonic scan can identify the bound excitonic states including negatively charged excitons much more efficiently, compared with the PL method at room temperature. Additionally, the MoSe{sub 2} monolayer exhibits a strong laser-induced damage threshold ∝16 GW cm{sup -2} under picosecond-pulse excitation{sub .} Our findings suggest that monolayer MoSe{sub 2} can be considered as a promising candidate for high-power, thin-film-based nonlinear optical devices and applications. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Two-dimensional MoS2 electromechanical actuators

    Science.gov (United States)

    Hung, Nguyen T.; Nugraha, Ahmad R. T.; Saito, Riichiro

    2018-02-01

    We investigate the electromechanical properties of two-dimensional MoS2 monolayers with 1H, 1T, and 1T‧ structures as a function of charge doping by using density functional theory. We find isotropic elastic moduli in the 1H and 1T structures, while the 1T‧ structure exhibits an anisotropic elastic modulus. Moreover, the 1T structure is shown to have a negative Poisson’s ratio, while Poisson’s ratios of the 1H and 1T‧ are positive. By charge doping, the monolayer MoS2 shows a reversible strain and work density per cycle ranging from  -0.68% to 2.67% and from 4.4 to 36.9 MJ m-3, respectively, making them suitable for applications in electromechanical actuators. We also examine the stress generated in the MoS2 monolayers and we find that 1T and 1T‧ MoS2 monolayers have relatively better performance than 1H MoS2 monolayer. We argue that such excellent electromechanical performance originate from the electrical conductivity of the metallic 1T and semimetallic 1T‧ structures and also from their high Young’s modulus of about 150-200 GPa.

  2. MoO3 incorporation in magnesium aluminosilicate glasses

    International Nuclear Information System (INIS)

    Tan, Shengheng; Ojovan, Michael I.; Hyatt, Neil C.; Hand, Russell J.

    2015-01-01

    Molybdate has a very low solubility in silicate and borosilicate glass systems and its excess presence in nuclear waste glass can cause the formation of a readily soluble “yellow phase”. In this study, the incorporation of molybdenum oxide (MoO 3 ) in a magnesium aluminosilicate glass system has been investigated. The prepared glasses show a higher than 90% molybdenum retention rate and up to 5.34 mol% (12.28 wt%) MoO 3 can be incorporated into these glasses without causing visible phase separation. The incorporation of MoO 3 increases glass density, decreases glass transition and crystallisation temperatures and intensifies Raman bands assigned to vibrations of MoO 4 2− units. When excess molybdate is added liquid–liquid phase separation and crystallisation occurs. The separated phase is spherical, 200–400 nm in diameter and randomly dispersed. Based on powder X-ray diffraction, Raman spectroscopy and transmission electron microscopy, the separated phase is identified as MgMoO 4

  3. MoO{sub 3} incorporation in magnesium aluminosilicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Shengheng; Ojovan, Michael I.; Hyatt, Neil C.; Hand, Russell J.

    2015-03-15

    Molybdate has a very low solubility in silicate and borosilicate glass systems and its excess presence in nuclear waste glass can cause the formation of a readily soluble “yellow phase”. In this study, the incorporation of molybdenum oxide (MoO{sub 3}) in a magnesium aluminosilicate glass system has been investigated. The prepared glasses show a higher than 90% molybdenum retention rate and up to 5.34 mol% (12.28 wt%) MoO{sub 3} can be incorporated into these glasses without causing visible phase separation. The incorporation of MoO{sub 3} increases glass density, decreases glass transition and crystallisation temperatures and intensifies Raman bands assigned to vibrations of MoO{sub 4}{sup 2−} units. When excess molybdate is added liquid–liquid phase separation and crystallisation occurs. The separated phase is spherical, 200–400 nm in diameter and randomly dispersed. Based on powder X-ray diffraction, Raman spectroscopy and transmission electron microscopy, the separated phase is identified as MgMoO{sub 4}.

  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. 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

  6. 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.

  7. An alternative route for the preparation of the medical isotope 99Mo from the 238U(γ, f) and 100Mo(γ, n) reactions

    International Nuclear Information System (INIS)

    Naik, H.; Goswami, A.; Suryanarayana, S.V.; Jagadeesan, K.C.; Thakare, S.V.; Joshi, P.V.; Nimje, V.T.; Mittal, K.C.; Venugopal, V.; Kailas, S.

    2013-01-01

    The radionuclide 99 Mo, which has a half-life of 65.94 h was produced from 238 U(γ, f) and 100 Mo(γ, n) reactions using a 10 MeV electron linac at EBC, Kharghar Navi-Mumbai, India. This has been investigated since the daughter product 99m Tc is very important from a medical point of view and can be produced in a generator from the parent 99 Mo. The activity of 99 Mo was analyzed by a γ-ray spectrometric technique using a HPGe detector. From the detected γ-rays activity of 140.5 and 739.8 keV, the amount of 99 Mo produced was determined. For comparison, the amount of 99 Mo from 238 U(γ, f) and 100 Mo(γ, n) reactions was also estimated using the experimental photon flux from 197 Au(γ, n) 196 Au reaction. The amount of 99 Mo from the detected γ-lines is in agreement with the estimated value for 238 U(γ, f) and 100 Mo(γ, n) reactions. The production of 99 Mo activity from 238 U(γ, f) and 100 Mo(γ, n) reactions is a relevant and novel approach, which provides alternative routes to 235,238 U(n, f) and 98 Mo(n, γ) reactions, circumventing the need for a reactor. The viability and practicality of the 99 Mo production from the 238 U(γ, f) and 100 Mo(γ, n) reactions alternative to 235,238 U(n, f) and 98 Mo(n, γ) reactions has been emphasize. An estimate has been also arrived based on the experimental data of present work to fulfill the requirement of DOE. (author)

  8. Minimisation of noble gas discharge from 99Mo production at ANSTO

    International Nuclear Information System (INIS)

    Blagojevic, N.; Izard, M.

    2001-01-01

    Full text: Molybdenum-99 is one of the most important radionuclides in modem medicine. When loaded on a chromatographic column it forms a generator that produces high specific activity 99m Tc, a radionuclide widely used in nuclear medical imaging. ANSTO has been a main producer of 99 Mo in the Australasian region since the late 1960's and currently ranks as one of the major suppliers of 99m Tc/ 99 Mo generators. At ANSTO 99 Mo is produced from enriched uranium oxide (2.2% 235 U) after a nominal seven day irradiation period in HIFAR, Australia's high flux research reactor. Between four and six targets are processed, four to five times each week depending on the reactor operation timetable. After irradiation the targets are allowed to decay for approximately 6 hours before the uranium dioxide pellets are removed and dissolved in a fully enclosed heated vessel equipped with a reflux column. The dissolver off-gas containing noble gases and iodine isotopes released during this process are vented through a caustic scrubber, a number of iodine traps and finally through a charcoal based Noble Gas Trap (NGT). The uranium solution is passed through an alumina column to separate molybdenum from other elements. The 99 Mo product is eluted from the column with relatively concentrated ammonium hydroxide solution. The product recovery process consists of a volume reduction procedure followed by a recovery step designed to retrieve the product in a minimum volume of dilute nitric acid. The radioactive Xe and Kr discharge was monitored using a Nal(TI) detector based gamma-ray spectrometer system that was interfaced to the internal computer network. The data was collected and sent to the network server at 15-minute intervals using locally written programs that process and database the information. The discharge data is displayed in real time by the use of web browsers found on all networked workstations. The network program is also capable of interrogating the database so that the

  9. Cryogenic deformation microstructures of 32Mn-7Cr-1Mo-0.3N austenitic steels

    International Nuclear Information System (INIS)

    Fu Ruidong; Qiu Liang; Wang Tiansheng; Wang Cunyu; Zheng Yangzeng

    2005-01-01

    The cryogenic deformation microstructures of impact and tensile specimens of 32Mn-7Cr-1Mo-0.3N austenitic steel were investigated using light microscopy and transmission electron microscopy. The results show that the deformation microstructures of the impact specimens are mainly composed of stacking faults, network dislocation, slip bands, and a few mechanical twins and ε-martensite. These microstructures cross with each other in a crystal angle. The deformation microstructures of the tensile specimens consist only of massive slip bands, in which a few mechanical twins and ε-martenite are located. Because of the larger plastic deformation the slip band traces become bent. All the deformation microstructures are formed on the {111} planes and along the orientation

  10. Study of the effect of irradiation of Mo targets at nuclear reactor

    International Nuclear Information System (INIS)

    Nieto, Renata C.; Lima, Ana Lucia V.P.; Silva, Nestor C. da; Osso Junior, Joao Alberto

    2000-01-01

    The most used radioisotope in nuclear medicine is 99m Tc, in the 99 Mo- 99m Tc generator form. 99 Mo can be produced by several nuclear reactions in reactors and cyclotrons. The cyclotron production is not technically and economically viable. The production in the reactor can be done in two different ways: by the fission of 235 U and by the 98 Mo(n,γ) 99 Mo reaction. A project for the production of 99 Mo by the activation of Mo and the preparation of gel type generators is under development at the 'Instituto de Pesquisas Energeticas e Nucleares'. In the present work, the radionuclidic impurities produced in the activation of MoO 3 , metallic Mo and Mo Zr gel were evaluated, as well as the radionuclidic purity of 99m Tc eluted from generators prepared. (author)

  11. 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. 

  12. Antisite disorder-induced low-field magnetoresistance in some frustrated Sr2FeMoO6

    International Nuclear Information System (INIS)

    Cai Tianyi; Ju Sheng; Li Zhenya

    2006-01-01

    Considering the existence of antiferromagnetic patches induced by the antisite disorder in ferrimagnetic Sr 2 FeMoO 6 , we have developed a resistor network model to account for the effects of the antisite disorder on the magnetoresistance in this material. It is proposed that the magnetic disorder resulting from the existence of frustration around the antiferromagnetic patches will be suppressed under the applied magnetic field and low-field magnetoresistance will be observed. For samples with low levels of antisite defects, the magnetoresistive behaviour may be strongly affected by the different degrees of magnetic inhomogeneity. Our calculated results are in agreement with experimental observations

  13. A first principle Comparative study of electronic and optical properties of 1H –MoS2 and 2H –MoS2

    International Nuclear Information System (INIS)

    Kumar, Ashok; Ahluwalia, P.K.

    2012-01-01

    First principle calculations of electronic and optical properties of monolayer MoS 2 , so called 1H –MoS 2 , is performed which has emerged as a new direct band gap semiconductor. Before calculations of the properties of 1H –MoS 2 , we have calculated structural parameters, electronic properties (electronic band structure and electronic density of states) and frequency dependent optical response (real and imaginary part of dielectric function, energy loss function, absorption and reflectance spectra) of 2H –MoS 2 and compared with existing experimental results and found that our calculated results are in very good agreements with experimental results. To compare the dielectric functions of bulk (2H –MoS 2 ) and monolayer (1H –MoS 2 ) phases we have further extended these calculations to the single layer MoS 2 (1H –MoS 2 ) which is analogous to graphene. Structural parameters of 1H –MoS 2 are found very close to its bulk 2H –MoS 2 . We find direct electronic band gap at ‘K’ high symmetry point as compared to indirect band gap in its bulk 2H – MoS2. Our calculated dielectric function for 1H – MoS2 shows structure at nearly same energy positions as compared to 2H – MoS2 with additional structure at 3.8 eV. Also additional well defined energy loss peaks revealing the plasmonic resonances at 15.7 eV and 16.0 eV for E vector perpendicular and parallel to c axis respectively for 1H – MoS2 have been found, which are the signatures of surface plasmons at these energies. -- Highlights: ► Structural parameters of 2H-MoS2 and 1H-MoS2 are nearly identical. ► States around the Fermi energy are mainly due to the metal d states. ► Strong hybridization between Mo-d and S-p states below the Fermi energy has been found. ► Optical spectra of 2H-MoS2 finds very good agreements with experimental optical spectra. ► The band gap is found to be direct for 1H-MoS2 as compared to indirect for 2H-MoS2.

  14. Development of improved HP/IP rotor material 2% CrMoNiWV (23 CrMoNiWV 88)

    International Nuclear Information System (INIS)

    Wiemann, W.

    1989-01-01

    The new 2% CrMoNiWV steel has a sufficient strength level, a very good creep (rupture) behaviour and an excellent toughness behaviour for a creep resistant steel. Even after long time high temperature exposure the toughness degradation is so small that it is still better than this of best 1% CrMo(Ni)V steels. The fatigue behaviour is well comparable to this of 1% CrMo(Ni)V. The 2% CrMoNiWV steel has the capability to substitute the traditional 1% CrMo(Ni)V. (orig.) With 26 annexes

  15. Effects of boron addition on the formation of MoSi2 by combustion synthesis mode

    International Nuclear Information System (INIS)

    Feng Peizhong; Wu Jie; Islam, S.H.; Liu Weisheng; Niu Jinan; Wang Xiaohong; Qiang Yinghuai

    2010-01-01

    The combustion synthesis behavior of Mo-Si-B powder was investigated. Test specimens with nominal compositions including MoSi 2 , Mo(Si 0.975 B 0.025 ) 2 , Mo(Si 0.95 B 0.05 ) 2 , Mo(Si 0.925 B 0.075 ) 2 and Mo(Si 0.9 B 0.1 ) 2 were employed. The combustion mode, propagation velocity of combustion wave, combustion temperature and combustion product structure were studied. The results showed that the combustion wave propagated along a spiral trajectory till reaching the bottom of the compacts. The combustion temperature was increased by the addition of boron, to as high as 1922 K in the case of the Mo(Si 0.95 B 0.05 ) 2 sample. However, the flame-front propagation velocity decreased as a result of the addition of boron. The X-ray diffraction results showed that the combustion products of the Mo(Si 0.975 B 0.025 ) 2 and Mo(Si 0.9 B 0.1 ) 2 samples were composed of MoSi 2 with minor MoB. Those of the Mo(Si 0.95 B 0.05 ) 2 and Mo(Si 0.925 B 0.075 ) 2 samples were composed of MoSi 2 with minor MoB and MoB 2 . And traces of Mo 2 B 5 were identified in the Mo(Si 0.95 B 0.05 ) 2 sample.

  16. Characterization of electrical resistivity as a function of temperature in the Mo-Si-B system

    International Nuclear Information System (INIS)

    Beckman, Sarah E.

    1999-01-01

    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: Mo 3 Si, Mo 5 SiB 2 , Mo 5 Si 3 B x , MoB, MoSi 2 , and Mo 5 Si 3 . Thesis materials all exhibit resistivity values within a narrow range(4--22 x 10 -7 Omega-m), and the low magnitude suggests these materials are semi-metals or low density of states metals. With the exception of MoSi 2 , 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 -10 Omega-m/degree C, and MoSi 2 had a TCR of 13.77 x 10 -10 Omega-m/degree 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 Mo 5 Si 3 -MoSi 2 system, the ternary phase field Mo 5 Si 3 B x MoB-MoSi 2 , and the Mo 3 Si-Mo 5 SiB 2 -Mo 5 Si 3 B x 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

  17. {sup 99}Mo sorption by thermally treated hydrotalcites

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, J.; Bertin, V.; Bulbulian, S.

    2000-04-04

    MoO{sub 4}{sup {minus}2} ions were sorbed in calcined hydrotalcite contained in a column. It was found that 98% of {sup 99m}Tc formed by {sup 99}Mo decay was eluted through the column in the form of pertechnetate. The content of radionuclides was determined by {gamma}-spectrometry, and natural molybdenum was measured by neutron activation analysis. Solids were characterized by thermal analysis, X-ray diffraction, and infrared spectroscopy. Through batch experiments, the hydrotalcite capacity toward molybdate ions (1.12 x 10{sup {minus}3} M) was found to be 3.2 mequiv g{sup {minus}1}. It was found that the high molybdate adsorbing capacity of calcined hydrotalcite could be utilized in designing a {sup 99m}Tc generator made with low specific activity {sup 99}Mo-molybdate samples.

  18. Nanocrystalline electrodeposited Ni-Mo-C cathodes for hydrogen production

    International Nuclear Information System (INIS)

    Hashimoto, K.; Sasaki, T.; Meguro, S.; Asami, K.

    2004-01-01

    Tailoring active nickel alloy cathodes for hydrogen evolution in a hot concentrated hydroxide solution was attempted by electrodeposition. The carbon addition to Ni-Mo alloys decreased the nanocrystalline grain size and remarkably enhanced the activity for hydrogen evolution, changing the mechanism of hydrogen evolution. The Tafel slope of hydrogen evolution was about 35 mV per decade. This suggested that the rate-determining step is desorption of adsorbed hydrogen atoms by recombination. As was distinct from the binary Ni-Mo alloys, after open circuit immersion, the overpotential, that is, the activity of nanocrystalline Ni-Mo-C alloys for hydrogen evolution was not changed, indicating the sufficient durability in the practical electrolysis

  19. U-Mo fuels handbook. Version 1.0

    International Nuclear Information System (INIS)

    Rest, Jeffrey; Kim, Yeon Soo; Hofman, Gerard L.; Meyer, Mitchell K.; Hayes, Steven L.

    2006-01-01

    This handbook provides an overview of property data and fuel performance topics with an emphasis on data available for U-Mo alloys. These data often exist only in report format and have not been widely disseminated in the journal literature. For some topics there is more than one source of data, which are sometimes inconsistent. In this situation, the authors have attempted to select the best dataset to provide a standard for fuel designers and reactor operators. Following the section on unirradiated and irradiated materials properties for the monolithic U-Mo alloy, property data for cladding and matrix aluminum are presented. Property data for cladding aluminum are more widely available, and are not presented in great depth. Finally, some properties of (U-Mo)/Al dispersions are also included in this document. Where no data are available, best estimate correlations are provided. Best fits to the data are presented in order to facilitate use by fuel designers and reactor operators.

  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. An experimental investigation of double beta decay of 100Mo

    International Nuclear Information System (INIS)

    Dougherty, B.L.

    1988-01-01

    New limits on half-lives for several double beta decay modes of 100 Mo were obtained with a novel experimental system which included thin source films interleaved with a coaxial array of windowless silicon detectors. Segmentation and timing information allowed backgrounds originating in the films to be studied in some detail. Dummy films containing 96 Mo were used to assess remaining backgrounds. With 0.1 mole years of 100 Mo data collected, the lower half-life limits at 90% confidence were 2.7 /times/ 10 18 years for decay via the two-neutrino mode, 5.2 /times/10 19 years for decay with the emission of a Majoron, and 1.6 /times/ 10 20 years and 2.2 /times/ 10 21 years for neutrinoless 0 + → 2 + and 0 + → 0 + transitions, respectively. 50 refs., 38 figs., 11 tabs

  2. Interdiffusion between U-Zr-Mo and stainless steel cladding

    International Nuclear Information System (INIS)

    Hwang, J. Y.; Lee, B. S.; Lee, J. T.; Kang, Y. H.

    1998-01-01

    Interdiffusion investigations were carried out at 700 deg C for 200 hours for the diffusion couples assembled with the U-Zr-Mo ternary fuel versus austenitic stainless steel D9 and the U-Zr-Mo ternary fuel versus martensitic stainless steel HT9 respectively to investigate the fuel-cladding compatibility. SEM-EDS analysis was utilized to determine the composition and the penetration depths of the reaction layers. In the case of Fuel/D9 couple, (Fe, Cr, Ni) of the cladding elements formed the precipitates with the Zr, Mo and diminished the U concentration upto 800μ length from the fuel side. Composition of the precipitates was varied with the penetrated elements. In Fuel/HT9 couple, reaction layer was smaller than that of D9 couples and was less affected by cladding elements. The eutectic reaction appeared partially in the Fuel/HT9 diffusion couple

  3. Ultrafast photocurrents in monolayer MoS2

    Science.gov (United States)

    Parzinger, Eric; Wurstbauer, Ursula; Holleitner, Alexander W.

    Two-dimensional transition metal dichalcogenides such as MoS2 have emerged as interesting materials for optoelectronic devices. In particular, the ultrafast dynamics and lifetimes of photoexcited charge carriers have attracted great interest during the last years. We investigate the photocurrent response of monolayer MoS2 on a picosecond time scale utilizing a recently developed pump-probe spectroscopy technique based on coplanar striplines. We discuss the ultrafast dynamics within MoS2 including photo-thermoelectric currents and the impact of built-in fields due to Schottky barriers as well as the Fermi level pinning at the contact region. We acknowledge support by the ERC via Project 'NanoREAL', the DFG via excellence cluster 'Nanosystems Initiative Munich' (NIM), and through the TUM International Graduate School of Science and Engineering (IGSSE) and BaCaTeC.

  4. Electrochromic properties of nanocrystalline MoO3 thin films

    International Nuclear Information System (INIS)

    Hsu, C.-S.; Chan, C.-C.; Huang, H.-T.; Peng, C.-H.; Hsu, W.-C.

    2008-01-01

    Electrochromic MoO 3 thin films were prepared by a sol-gel spin-coating technique. The spin-coated films were initially amorphous; they were calcined, producing nanocrystalline MoO 3 thin films. The effects of annealing temperatures ranging from 100 o C to 500 o C were investigated. The electrochemical and electrochromic properties of the films were measured by cyclic voltammetry and by in-situ optical transmittance techniques in 1 M LiClO 4 /propylene carbonate electrolyte. Experimental results showed that the transmittance of MoO 3 thin films heat-treated at 350 o C varied from 80% to 35% at λ = 550 nm (ΔT = ∼ 45%) and from 86% to 21% at λ ≥ 700 nm (ΔT = ∼ 65%) after coloration. Films heat-treated at 350 deg. C exhibited the best electrochromic properties in the present study

  5. Progress in Establishment of Fission Mo Production Technology in Korea

    International Nuclear Information System (INIS)

    Lee, Jun Sig

    2013-01-01

    Research activities have been made in both the development of the fission Mo production process and the designing of the production facility that will be established at Kijang, Korea including a new research reactor in 2017. Progress in the process development for target preparation, target dissolution, Mo extraction, and purification has been made. It is also a great concern to minimize the radioactive wastes or at least to generate the wastes in readily treatable forms in the project. After series of cold experiments, the target dissolution and solution formulation for a column operation are optimized. Progress in the design of the production facility has been made. Two trains of hot cells including the waste storages have been proposed for the alternative operation of the facility. A radioisotope production facility is designed to locate next to the fission Mo production building to provide a simpler and easier handling pathway of the products

  6. 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

  7. Crystal Structure of Na3MoCl6

    Directory of Open Access Journals (Sweden)

    Martin Beran

    2011-07-01

    Full Text Available The ternary chloride Na3MoCl6 is obtained as red crystals from a disproportionation reaction of molybdenum dichloride, {Mo6}Cl12, in an acidic NaCl/AlCl3 melt at 350 °C. The crystal structure (trigonal, P-31c, a = 687.1(1, c = 1225.3(2 pm, Z = 2, V = 501,0(1 106 pm3 is that of Na3CrCl6: within a hexagonal closest-packing of chloride ions two thirds of the octahedral voids are filled between the AB double layers with Na+/Mo3+, and between the BA layers with Na+.

  8. Production of Mo-99 using low-enriched uranium silicide

    International Nuclear Information System (INIS)

    Hutter, J.C.; Srinivasan, B.; Vicek, M.; Vandegrift, G.F.

    1994-01-01

    Over the last several years, uranium silicide fuels have been under development as low-enriched uranium (LEU) targets for Mo-99. The use of LEU silicide is aimed at replacing the UAl x alloy in the highly-enriched uranium dissolution process. A process to recover Mo-99 from low-enriched uranium silicide is being developed at Argonne National Laboratory. The uranium silicide is dissolved in alkaline hydrogen peroxide. Experiments performed to determine the optimum dissolution procedure are discussed, and the results of dissolving a portion of a high-burnup (>40%) U 3 Si 2 miniplate are presented. Future work related to Mo-99 separation and waste disposal are also discussed

  9. 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....... These include student relations and interactions and epistemic and linguistic networks of words, concepts and actions. Network methodology has already found use in science education research. However, while networks hold the potential for new insights, they have not yet found wide use in the science education...... 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...

  10. Network Convergence

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Network Convergence. User is interested in application and content - not technical means of distribution. Boundaries between distribution channels fade out. Network convergence leads to seamless application and content solutions.

  11. Industrial Networks

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    Companies organize in a way that involves many activities that are external to the traditional organizational boundaries. This presents challenges to operations management and managing operations involves many issues and actions dealing with external networks. Taking a network perspective changes...

  12. Network Science

    National Research Council Canada - National Science Library

    Leland, Will

    2006-01-01

    OVERVIEW: (1) A committee of technical experts, military officers and R&D managers was assembled by the National Research Council to reach consensus on the nature of networks and network research. (2...

  13. Ligand bridging-angle-driven assembly of molecular architectures based on quadruply bonded Mo-Mo dimers.

    Science.gov (United States)

    Li, Jian-Rong; Yakovenko, Andrey A; Lu, Weigang; Timmons, Daren J; Zhuang, Wenjuan; Yuan, Daqiang; Zhou, Hong-Cai

    2010-12-15

    A systematic exploration of the assembly of Mo2(O2C-)4-based metal-organic molecular architectures structurally controlled by the bridging angles of rigid organic linkers has been performed. Twelve bridging dicarboxylate ligands were designed to be of different sizes with bridging angles of 0, 60, 90, and 120° while incorporating a variety of nonbridging functional groups, and these ligands were used as linkers. These dicarboxylate linkers assemble with quadruply bonded Mo-Mo clusters acting as nodes to give 13 molecular architectures, termed metal-organic polygons/polyhedra with metal cluster node arrangements of a linear shape, triangle, octahedron, and cuboctahedron/anti-cuboctahedron. The syntheses of these complexes have been optimized and their structures determined by single-crystal X-ray diffraction. The results have shown that the shape and size of the resulting molecular architecture can be controlled by tuning the bridging angle and size of the linker, respectively. Functionalization of the linker can adjust the solubility of the ensuing molecular assembly but has little or no effect on the geometry of the product. Preliminary gas adsorption, spectroscopic, and electrochemical properties of selected members were also studied. The present work is trying to enrich metal-containing supramolecular chemistry through the inclusion of well-characterized quadruply bonded Mo-Mo units into the structures, which can widen the prospect of additional electronic functionality, thereby leading to novel properties.

  14. Determination of 99Mo contamination in 99mTc elute obtained from 99Mo/99mTc- generator

    International Nuclear Information System (INIS)

    Momennezhad, M.; Zakavi, S. R.; Sadeghi, R.

    2010-01-01

    99m Tc is a widely used radioisotope in nuclear medicine centers which is obtained by elution from Mo-99/Tc-99m generators. Usually the generators are either supplied by the Iran Atomic Energy Agency or by private companies from foreign countries. In this study we have measured 99 Mo contamination in 99m Tc elute from different generators in a period of one year. Materials and Methods: The radionuclide impurity of the 99m Tc elute were studied in two types of radionuclide generators (A: produced in Iran and B: Imported from other country). In-vitro measurements were performed using dose calibrator. Direct measurements were made, using a standard canister at the time of milking of the generators and also in Subsequent hours after milking. Results: The results showed a mean of 99 Mo impurity in generators A and B to be 0.00932±0.0043 and 0.0170±0.0127 respectively. Although the results showed that the 99 Mo contamination in 99 mTc elute was lesser than the maximum accepted activity limit of 0.015%, the difference in these two types may reflect different methods of productions of generator, as well as the quality control procedures. Conclusion: The mean of 99 Mo contamination in generators produced in Iran Atomic Energy Organization was lesser than generators imported from foreign origin.

  15. 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...

  16. Network Simulation

    CERN Document Server

    Fujimoto, Richard

    2006-01-01

    "Network Simulation" presents a detailed introduction to the design, implementation, and use of network simulation tools. Discussion topics include the requirements and issues faced for simulator design and use in wired networks, wireless networks, distributed simulation environments, and fluid model abstractions. Several existing simulations are given as examples, with details regarding design decisions and why those decisions were made. Issues regarding performance and scalability are discussed in detail, describing how one can utilize distributed simulation methods to increase the

  17. 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.

  18. Thermal and x-ray studies on Tl2U(MoO4)3 and Tl4U(MoO4)4

    International Nuclear Information System (INIS)

    Dahale, N.D.; Keskar, Meera; Kulkarni, N.K.; Singh Mudher, K.D.

    2006-01-01

    In the quaternary Tl-U(IV)-Mo-O system, two new compounds namely Tl 2 U(MoO 4 ) 3 and Tl 4 U(MoO 4 ) 4 were prepared and characterized by powder X-ray diffraction and thermal methods. These compounds were prepared by solid state reactions of Tl 2 MoO 4 , UMoO 5 and MoO 3 in the required stoichiometric ratio at 500 deg C in evacuated sealed quartz ampoule. The XRD data of Tl 2 U(MoO 4 ) 3 and Tl 4 U(MoO 4 ) 4 were indexed on orthorhombic cell. TG curves of Tl 2 U(MoO 4 ) 3 and Tl 4 U(MoO 4 ) 4 did not show any weight change up to 700 deg C in an inert atmosphere. During heating in an inert atmosphere, Tl 2 U(MoO 4 ) 3 and Tl 4 U(MoO 4 ) 4 showed endothermic Dta peaks due to melting of the compounds at 519 and 565 deg C, respectively. (author)

  19. Enhanced field emission behavior of layered MoSe2

    International Nuclear Information System (INIS)

    Suryawanshi, Sachin R; Pawbake, Amit S; Jadkar, Sandesh R; More, Mahendra A; Pawar, Mahendra S; Late, Dattatray J

    2016-01-01

    Herein, we report one step facile chemical vapor deposition method for synthesis of single-layer MoSe 2 nanosheets with average lateral dimension ∼60 μm on 300 nm SiO 2 /Si and n-type silicon substrates and field emission investigation of MoSe 2 /Si at the base pressure of ∼1 × 10 −8 mbar. The morphological and structural analyses of the as-deposited single-layer MoSe 2 nanosheets were carried out using an optical microscopy, Raman spectroscopy and atomic force microscopy. Furthermore, the values of turn-on and threshold fields required to extract an emission current densities of 1 and 10 μA cm −2 , are found to be ∼1.9 and ∼2.3 V μm −1 , respectively. Interestingly, the MoSe 2 nanosheet emitter delivers maximum field emission current density of ∼1.5 mA cm −2 at a relatively lower applied electric field of ∼3.9 V μm −1 . The long term operational current stability recorded at the preset values of 35 μA over 3 hr duration and is found to be very good. The observed results demonstrates that the layered MoSe 2 nanosheet based field emitter can open up many opportunities for their potential application as an electron source in flat panel display, transmission electron microscope, and x-ray generation. Thus, the facile one step synthesis approach and robust nature of single-layer MoSe 2 nanosheets emitter can provide prospects for the future development of practical electron sources. (paper)

  20. Investigation of the fabrication process of hot-worked stainless-steel and Mo sheathed PbMo6 S8 wires

    International Nuclear Information System (INIS)

    Yamasaki, H.; Kimura, Y.

    1988-01-01

    Stainless-steel and Mo sheathed PbMo 6 S 8 wires have been fabricated by hot working from modified PbS, Mo, and MoS 2 mixed powders which were prepared by reacting Pb, Mo, and S at 530 0 C. Critical current densities were investigated for different preparation conditions, and it is revealed that obtaining continuous current path between PbMo 6 S 8 grains is the most important factor to achieve high critical current density. The J/sub c/ value of 2.8 x 10 4 Acm 2 (8 T), 7.8 x 10 3 Acm 2 (15 T), and 1.3 x 10 3 Acm 2 (23 T) was observed for the PbMo 6 S/sub 7.0/ wire heat treated at 700 0 C.copic

  1. 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.

  2. Cyclic Oxidation of High Mo, Reduced Density Superalloys

    Directory of Open Access Journals (Sweden)

    James L. Smialek

    2015-11-01

    Full Text Available Cyclic oxidation was characterized as part of a statistically designed, 12-alloy compositional study of 2nd generation single crystal superalloys as part of a broader study to co-optimize density, creep strength, and cyclic oxidation. The primary modification was a replacement of 5 wt. % W by 7% or 12% Mo for density reductions of 2%–7%. Compositions at two levels of Mo, Cr, Co, and Re were produced, along with a midpoint composition. Initially, polycrystalline vacuum induction samples were screened in 1100 °C cyclic furnace tests using 1 h cycles for 200 h. The behavior was primarily delimited by Cr content, producing final weight changes of −40 mg/cm2 to −10 mg/cm2 for 0% Cr alloys and −2 mg/cm2 to +1 mg/cm2 for 5% Cr alloys. Accordingly, a multiple linear regression fit yielded an equation showing a strong positive Cr effect and lesser negative effects of Co and Mo. The results for 5% Cr alloys compare well to −1 mg/cm2, and +0.5 mg/cm2 for Rene′ N4 and Rene′ N5 (or Rene′ N6, respectively. Scale phases commonly identified were Al2O3, NiAl2O4, NiTa2O6, and NiO, with (Ni,CoMoO4 found only on the least resistant alloys having 0% Cr and 12% Mo. Scale microstructures were complex and reflected variations in the regional spallation history. Large faceted NiO grains and fine NiTa2O6 particles distributed along NiAl2O4 grain boundaries were typical distinctive features. NiMoO4 formation, decomposition, and volatility occurred for a few high Mo compositions. A creep, density, phase stability, and oxidation balanced 5% Cr, 10% Co, 7% Mo, and 3% Re alloy was selected to be taken forward for more extensive evaluations in single crystal form.

  3. 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)

  4. Characterization of wastes from fission 99 Mo production

    International Nuclear Information System (INIS)

    Endo, L.S.; Dellamano, J.C.

    1992-07-01

    This work is a preliminary study on waste-streams generated in a fission 99 Mo production plant, their characterization and quantification. The study is based on a plant whose 99 Mo production process is the alkaline dissolution of U-target. The target is made of 1 g of enriched 235 U, therefore most of radionuclides present in the waste-streams are fission products. All the radionuclides inventories were estimated based on ORIGEN-2 Code. The characterization was done as a primary stage for the establishment of waste management plan, which should be subject for further study. (author)

  5. Properties of MoO3 thin film polymorphs

    International Nuclear Information System (INIS)

    McCarron, E.M.; Carcia, P.F.

    1987-01-01

    Thin film polymorphs of molybdenum trioxide have been synthesized by RF sputtering. Films deposited on thermally floating substrates are polycrystalline and exhibit preferred orientation. Depending upon the oxygen partial pressure maintained during sputtering, the films can be made to crystallize in either the thermodynamically stable orthorhombic α MoO 3 form (unique 2D-layered structure) or the metastable monoclinic β MoO 3 phase (3D ReO 3 -related structure). Metastable β films can be converted thermally to the α phase and the transformation appears topotactic. Films deposited on the cooled substrates are amorphous. A correlation between the particular phase formed and adatom mobility is noted

  6. Conduction quantization in monolayer MoS2

    Science.gov (United States)

    Li, T. S.

    2016-10-01

    We study the ballistic conduction of a monolayer MoS2 subject to a spatially modulated magnetic field by using the Landauer-Buttiker formalism. The band structure depends sensitively on the field strength, and its change has profound influence on the electron conduction. The conductance is found to demonstrate multi-step behavior due to the discrete number of conduction channels. The sharp peak and rectangular structures of the conductance are stretched out as temperature increases, due to the thermal broadening of the derivative of the Fermi-Dirac distribution function. Finally, quantum behavior in the conductance of MoS2 can be observed at temperatures below 10 K.

  7. Study on the Ni Mo alloy nano crystals

    International Nuclear Information System (INIS)

    Goncalves, Lidice A. Pereira; Pontes, Luiz Renato de Araujo

    1996-01-01

    Materials with nanocrystalline microstructures are solids that contain such a high density of defects, with the spacings between neighboring defects approaching interatomic distances. As result, nanocrystalline solids exhibit physical and chemical properties different from those usually found in normal crystalline s or amorphous materials with the same chemical composition. In this work, the nanocrystalline Ni Mo alloy was prepared by melt-spinning method. The novelly synthesized nanocrystalline Ni Mo alloy was characterized by X-ray diffraction (XRD), differential scanning calorimetry (D S C) and microscopy. The estimated average crystalline size by the Debye-Scherrer formulas was 20 nm. (author)

  8. Engineering Ni-Mo-S Nanoparticles for Hydrodesulfurization

    DEFF Research Database (Denmark)

    Bodin, Anders; Christoffersen, Ann-Louise N.; Elkjær, Christian F.

    2018-01-01

    Nanoparticle engineering for catalytic applications requires both a synthesis technique for the production of well-defined nanoparticles and measurements of their catalytic performance. In this paper, we present a new approach to rationally engineering highly active Ni-Mo-S nanoparticle catalysts...... for hydrodesulfurization (HDS), i.e., the removal of sulfur from fossil fuels. Nanoparticle catalysts are synthesized by the sputtering of a Mo75Ni25 metal target in a reactive atmosphere of Ar and H2S followed by the gas aggregation of the sputtered material into nanoparticles. The nanoparticles are filtered...

  9. Tensile and impact properties of TZM and Mo-5% Re

    International Nuclear Information System (INIS)

    Filacchioni, G.; Casagrande, E.; Angelis, U. de; Santis, G. de; Ferrara, D.

    1994-01-01

    Some aspects of the mechanical behaviour of two molybdenum alloys, one belonging to the precipitation hardened sub-family (TZM) and the other is a solid solution Mo 5% rhenium-bearing alloy, have been investigated. Experimental data (tensile mechanical strength, ductility and impact properties of unirradiated materials) show that a difference in behaviour exists between the precipitation hardened and the solid solution strengthened alloy, but at the same time a serious discrepancy has been found between the present results and previously reported ductile to brittle transition temperature values for Mo alloys. ((orig.))

  10. Spectroscopy, microscopy and theoretical study of NO adsorption on MoS2 and Co-Mo-S hydrotreating catalysts

    DEFF Research Database (Denmark)

    Topsøe, Nan-Yu; Tuxen, Anders Kyrme; Hinnemann, Berit

    2011-01-01

    nfrared (IR) spectroscopy using NO as a probe molecule has been one of the important methods for characterizing hydrotreating catalysts, since this technique provides information on the nature and quantity of active edge sites of these catalysts. However, due to the strong adsorption of NO, which......) calculations, we present new atomic-scale insight into the nature of NO adsorption on MoS2 and Co-Mo-S nanoclusters. The DFT calculations and STM experiments show that NO does not adsorb at fully sulfided MoS2 edges not containing hydrogen. However, typical sulfided catalysts will have hydrogen present...... NO as a probe molecule to obtain detailed atomic-scale information on hydrotreating catalysts and the origins of activity differences. (C) 2011 Published by Elsevier Inc....

  11. Performance of Tc-99m generator prepared with Mo adsorbent PZC and irradiated nature MoO3

    International Nuclear Information System (INIS)

    Liu Yishu

    2006-01-01

    This paper describes the technical process of Tc-99m generator prepared with reactor actived Mo-99 and PZC and the performance of the generator was also reported. Two generators were prepared with different batch of PZC and by different technical process. The results show that the adsorption rate was ∼65% and the adsorption efficiency of 99 Mo can be seriously affected by the adsorption process (the temperature, intensity and frequency of shaking and the PZC volume in solution etc.). The elution efficiency was 43-73%. The Mo breakthrough 1.2 - 16% without safe column and its can be decreased to be very low by connecting a hydrate zirconia (HZO) safe column. (author)

  12. Carbon potential measurement on the Mo-MoC0.47 system by methane - hydrogen equilibration

    International Nuclear Information System (INIS)

    Ananthasivan, K.; Kaliappan, I.; Chandramouli, V.; Anthonysamy, S.; Vasudeva Rao, P.R.; Mathews, C.K.

    1993-01-01

    Uranium plutonium mixed carbides are potential candidate fuel materials for liquid metal cooled fast breeder reactors. The carbon potential of the fuel is an important thermochemical property which strongly influences the carbon transport between the clad and the fuel. The carbon potential of the fuel is altered during irradiation of the fuel in the reactor. This is due to the formation of various fission products and their binary and ternary carbides. Molybdenum is a fission product with a high yield which can alter the carbon potential of the fuel. The present work forms part of our studies on the carbon potential measurements in the U - Mo - C ternary system. The carbon potential of the Mo-Mo 2 C couple measured by the methane hydrogen gas equilibration technique is presented here and the results are compared with the values cited in the literature. (author)

  13. High Q ceramics in the ACe2(MoO4)4 (A = Ba, Sr and Ca) system for LTCC applications

    International Nuclear Information System (INIS)

    Surjith, A.; Ratheesh, R.

    2013-01-01

    Highlights: ► Solid state synthesis of phase pure ACe 2 (MoO 4 ) 4 (A = Ba, Sr and Ca) ceramics. ► Structural and microstructural evaluation of the synthesized ceramic materials. ► Microwave dielectric property studies of ACe 2 (MoO 4 ) 4 (A = Ba, Sr and Ca) ceramics. ► Structure-property correlation through Laser Raman studies. - Abstract: Novel low temperature sinterable high Q ceramic systems ACe 2 (MoO 4 ) 4 (A = Ba, Sr and Ca) have been prepared through solid state ceramic method. The effect of ionic radii of alkaline earth cations on the structure, microstructure and microwave dielectric properties of these ceramics were studied using powder X-ray diffraction, Laser Raman spectroscopy, scanning electron microscopy and Vector Network Analyzer. A structural change from monoclinic to tetragonal structure was observed while substituting Sr 2+ and Ca 2+ cations in place of Ba 2+ . The Sr and Ca analogues possess better microwave dielectric properties compared to BaCe 2 (MoO 4 ) 4 . All the ceramics were well sintered below 840 °C with dielectric constant in the range 10.2–12.3 together with good quality factor. The SrCe 2 (MoO 4 ) 4 ceramic exhibits an unloaded quality factor of 6762 at 8.080662 GHz with a temperature coefficient of resonant frequency of −46 ppm/°C while the CaCe 2 (MoO 4 ) 4 ceramic shows an unloaded quality factor of 7549 at 6.928868 GHz and a temperature coefficient of resonant frequency of −44 ppm/°C.

  14. 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

  15. KiMoSys: a web-based repository of experimental data for KInetic MOdels of biological SYStems.

    Science.gov (United States)

    Costa, Rafael S; Veríssimo, André; Vinga, Susana

    2014-08-13

    The kinetic modeling of biological systems is mainly composed of three steps that proceed iteratively: model building, simulation and analysis. In the first step, it is usually required to set initial metabolite concentrations, and to assign kinetic rate laws, along with estimating parameter values using kinetic data through optimization when these are not known. Although the rapid development of high-throughput methods has generated much omics data, experimentalists present only a summary of obtained results for publication, the experimental data files are not usually submitted to any public repository, or simply not available at all. In order to automatize as much as possible the steps of building kinetic models, there is a growing requirement in the systems biology community for easily exchanging data in combination with models, which represents the main motivation of KiMoSys development. KiMoSys is a user-friendly platform that includes a public data repository of published experimental data, containing concentration data of metabolites and enzymes and flux data. It was designed to ensure data management, storage and sharing for a wider systems biology community. This community repository offers a web-based interface and upload facility to turn available data into publicly accessible, centralized and structured-format data files. Moreover, it compiles and integrates available kinetic models associated with the data.KiMoSys also integrates some tools to facilitate the kinetic model construction process of large-scale metabolic networks, especially when the systems biologists perform computational research. KiMoSys is a web-based system that integrates a public data and associated model(s) repository with computational tools, providing the systems biology community with a novel application facilitating data storage and sharing, thus supporting construction of ODE-based kinetic models and collaborative research projects.The web application implemented using Ruby

  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. 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

  18. Highly Enhanced Gas Adsorption Properties in Vertically Aligned MoS2 Layers.

    Science.gov (United States)

    Cho, Soo-Yeon; Kim, Seon Joon; Lee, Youhan; Kim, Jong-Seon; Jung, Woo-Bin; Yoo, Hae-Wook; Kim, Jihan; Jung, Hee-Tae

    2015-09-22

    In this work, we demonstrate that gas adsorption is significantly higher in edge sites of vertically aligned MoS2 compared to that of the conventional basal plane exposed MoS2 films. To compare the effect of the alignment of MoS2 on the gas adsorption properties, we synthesized three distinct MoS2 films with different alignment directions ((1) horizontally aligned MoS2 (basal plane exposed), (2) mixture of horizontally aligned MoS2 and vertically aligned layers (basal and edge exposed), and (3) vertically aligned MoS2 (edge exposed)) by using rapid sulfurization method of CVD process. Vertically aligned MoS2 film shows about 5-fold enhanced sensitivity to NO2 gas molecules compared to horizontally aligned MoS2 film. Vertically aligned MoS2 has superior resistance variation compared to horizontally aligned MoS2 even with same surface area exposed to identical concentration of gas molecules. We found that electrical response to target gas molecules correlates directly with the density of the exposed edge sites of MoS2 due to high adsorption of gas molecules onto edge sites of vertically aligned MoS2. Density functional theory (DFT) calculations corroborate the experimental results as stronger NO2 binding energies are computed for multiple configurations near the edge sites of MoS2, which verifies that electrical response to target gas molecules (NO2) correlates directly with the density of the exposed edge sites of MoS2 due to high adsorption of gas molecules onto edge sites of vertically aligned MoS2. We believe that this observation extends to other 2D TMD materials as well as MoS2 and can be applied to significantly enhance the gas sensor performance in these materials.

  19. OPAL: prediction of MoRF regions in intrinsically disordered protein sequences.

    Science.gov (United States)

    Sharma, Ronesh; Raicar, Gaurav; Tsunoda, Tatsuhiko; Patil, Ashwini; Sharma, Alok

    2018-06-01

    Intrinsically disordered proteins lack stable 3-dimensional structure and play a crucial role in performing various biological functions. Key to their biological function are the molecular recognition features (MoRFs) located within long disordered regions. Computationally identifying these MoRFs from disordered protein sequences is a challenging task. In this study, we present a new MoRF predictor, OPAL, to identify MoRFs in disordered protein sequences. OPAL utilizes two independent sources of information computed using different component predictors. The scores are processed and combined using common averaging method. The first score is computed using a component MoRF predictor which utilizes composition and sequence similarity of MoRF and non-MoRF regions to detect MoRFs. The second score is calculated using half-sphere exposure (HSE), solvent accessible surface area (ASA) and backbone angle information of the disordered protein sequence, using information from the amino acid properties of flanks surrounding the MoRFs to distinguish MoRF and non-MoRF residues. OPAL is evaluated using test sets that were previously used to evaluate MoRF predictors, MoRFpred, MoRFchibi and MoRFchibi-web. The results demonstrate that OPAL outperforms all the available MoRF predictors and is the most accurate predictor available for MoRF prediction. It is available at http://www.alok-ai-lab.com/tools/opal/. ashwini@hgc.jp or alok.sharma@griffith.edu.au. Supplementary data are available at Bioinformatics online.

  20. Oxygen potential of a prototypic Mo-cermet fuel containing plutonium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, Shuhei, E-mail: miwa.shuhei@jaea.go.jp [Japan Atomic Energy Agency, 4002 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki, 311-1393 (Japan); Osaka, Masahiko [Japan Atomic Energy Agency, 4002 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki, 311-1393 (Japan); Nozaki, Takahiro; Arima, Tatsumi; Idemitsu, Kazuya [Kyushu University, 744 Motooka Nishi-ku, Fukuoka, 819-0395 (Japan)

    2015-10-15

    Oxygen potential of a prototypic Mo-cermet fuel containing 50 vol.% PuO{sub 2−x} were investigated by the thermogravimetric analysis in the temperature range from 1273 K to 1473 K. It was shown that the oxygen potential and oxidation rate of the Mo-cermet were the same as those of pure PuO{sub 2−x} below the oxygen potential of Mo/MoO{sub 2} oxidation reaction. The same features of the Mo-cermet sample containing 50 vol.% PuO{sub 2−x} with those of pure PuO{sub 2−x} were discussed in terms of the microstructure. - Highlights: • Oxygen potential of Mo-cermet fuel was investigated by thermogravimetric analysis. • It was the same as that of pure PuO{sub 2−x} below the oxygen potential for Mo/MoO{sub 2}. • Gradual oxidation of Mo matrix occurred only above the oxygen potential for Mo/MoO{sub 2}. • Mo matrix and PuO{sub 2−x} in Mo-cermet fuel can thus be thermochemically individual.

  1. Oxygen potential of a prototypic Mo-cermet fuel containing plutonium oxide

    International Nuclear Information System (INIS)

    Miwa, Shuhei; Osaka, Masahiko; Nozaki, Takahiro; Arima, Tatsumi; Idemitsu, Kazuya

    2015-01-01

    Oxygen potential of a prototypic Mo-cermet fuel containing 50 vol.% PuO_2_−_x were investigated by the thermogravimetric analysis in the temperature range from 1273 K to 1473 K. It was shown that the oxygen potential and oxidation rate of the Mo-cermet were the same as those of pure PuO_2_−_x below the oxygen potential of Mo/MoO_2 oxidation reaction. The same features of the Mo-cermet sample containing 50 vol.% PuO_2_−_x with those of pure PuO_2_−_x were discussed in terms of the microstructure. - Highlights: • Oxygen potential of Mo-cermet fuel was investigated by thermogravimetric analysis. • It was the same as that of pure PuO_2_−_x below the oxygen potential for Mo/MoO_2. • Gradual oxidation of Mo matrix occurred only above the oxygen potential for Mo/MoO_2. • Mo matrix and PuO_2_−_x in Mo-cermet fuel can thus be thermochemically individual.

  2. 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.

  3. Feasibility study on mass production of (n,γ)99Mo

    International Nuclear Information System (INIS)

    Jun, Byung Jin; Tanimoto, Masataka; Kimura, Akihiro; Hori, Naohiko; Izumo, Hironobu; Tsuchiya, Kunihiko

    2011-01-01

    The world is currently suffering from a severe shortage of 99 Mo and various efforts have been given for its availability. The (n,γ) method is one of candidates for the alternative supply of 99 Mo. The only but critical shortage of (n,γ) 99 Mo is its extremely low specific activity, which gives inconveniency in the extraction of 99m Tc and is consequently converted to additional cost. Potential technologies which make the (n,γ) 99 Mo competitive by reducing the additional cost are already available. It is expected that verification of such technologies is much easy and cost effective compared to any other options known for the alternative 99 Mo production. Because Japan and Korea import all 99 Mo from long distance, the cost benefit of local (n,γ) 99 Mo production in these countries is especially large. If five high flux reactors in China, Japan and Korea are utilized for the cross backup supply of (n,γ) 99 Mo, stable availability of 99 Mo in the region can be secured. Therefore, it is necessary to evaluate its feasibility on (n,γ) 99 Mo production in the Asia region. In this report, we studied feasibility of the mass (n,γ) 99 Mo production from viewpoints of global and regional status of 99 Mo demand and supply, competitiveness with other production methods, requirements and flow of the 99 Mo, production capability, cost, convenience in usage, and alternative technologies to overcome its shortage. (author)

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

    KAUST Repository

    Muralikrishna, S.; Manjunath, K.; Samrat, D.; Reddy, Viswanath; Ramakrishnappa, T.; Nagaraju, Doddahalli H.

    2015-01-01

    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.

  5. Spatial networks

    Science.gov (United States)

    Barthélemy, Marc

    2011-02-01

    Complex systems are very often organized under the form of networks where nodes and edges are embedded in space. Transportation and mobility networks, Internet, mobile phone networks, power grids, social and contact networks, and neural networks, are all examples where space is relevant and where topology alone does not contain all the information. Characterizing and understanding the structure and the evolution of spatial networks is thus crucial for many different fields, ranging from urbanism to epidemiology. An important consequence of space on networks is that there is a cost associated with the length of edges which in turn has dramatic effects on the topological structure of these networks. We will thoroughly explain the current state of our understanding of how the spatial constraints affect the structure and properties of these networks. We will review the most recent empirical observations and the most important models of spatial networks. We will also discuss various processes which take place on these spatial networks, such as phase transitions, random walks, synchronization, navigation, resilience, and disease spread.

  6. 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...

  7. 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.

  8. On several new ternary molybdenum sulfide phases M/sub 3.4/Mo/sub 15/S/sub 19/ (M = vacancy, Li, Na, K, Zn, Cd, Sn and Tl)

    International Nuclear Information System (INIS)

    Tarascon, J.M.; Hull, G.W.

    1986-01-01

    In/sub 3.3/Mo/sub 15/Se/sub 19/ was reported a few years ago, but many attempts to date to prepare the homologue sulfide were unsuccessful. The authors report herein the first synthesis of In/sub 3.4/Mo/sub 15/S/sub 19/, isostructural to the above selenide and show that indium atoms can be removed from this phase by oxidation with HCl without disturbing the Mo chalcogenide network resulting in a new binary phase Mo/sub 15/S/sub 19/. Furthermore, this phase, with an open framework structure turns out to be an interesting system for intercalation studies. The authors have shown that Mo/sub 15/S/sub 19/ can undergo topotactic redox reactions with lithium or sodium resulting in new phases of formula Li/sub 8/Mo/sub 15/S/sub 19/ respectively. These two phases are stable at room temperature in the absence of air

  9. Controlled formation of MoSe{sub 2} by MoN{sub x} thin film as a diffusion barrier against Se during selenization annealing for CIGS solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Chan-Wook [School of Chemical Engineering, Yeungnam University, Gyeongsangbuk-do 712-749 (Korea, Republic of); Cheon, Taehoon [School of Materials Science and Engineering, Yeungnam University, Gyeongsangbuk-do 712-749 (Korea, Republic of); Center for Core Research Facilities, DaeguGyeongbuk Institute of Science & Technology, Daegu (Korea, Republic of); Kim, Hangil [School of Materials Science and Engineering, Yeungnam University, Gyeongsangbuk-do 712-749 (Korea, Republic of); Kwon, Min-Su [School of Chemical Engineering, Yeungnam University, Gyeongsangbuk-do 712-749 (Korea, Republic of); Kim, Soo-Hyun [School of Materials Science and Engineering, Yeungnam University, Gyeongsangbuk-do 712-749 (Korea, Republic of)

    2015-09-25

    Highlights: • Mo/MoN{sub x}/Mo multilayer was investigated as a back contact for CIGS solar cell. • The MoN{sub x} protected the underlying Mo layer during high temperature selenization. • The formation of MoSe{sub 2} layer was precisely controlled. • The diffusion barrier performance of MoN{sub x} against Se was evaluated using TEM analysis. - Abstract: This study investigated the interfacial reactions and electrical properties of a Mo single layer and Mo/MoN{sub x}/Mo multilayer during high temperature selenization annealing. The Mo single layer was converted easily to MoSe{sub 2}, which was 7 times thicker than the Mo layer consumed ∼900 nm, by selenization at 460 °C for 10 min and the sheet resistance increased 8 fold compared to that of the as-deposited Mo film. On the other hand, in the Mo/MoN{sub x}/Mo structure, transmission electron microscopy (TEM) showed that the MoSe{sub 2} transformation was localized only in the top Mo layer and the bottom Mo layer was completely unaffected, even after selenization at 560 °C. The sheet resistance of the multilayer was relatively unchanged by selenization. This suggests that the MoN{sub x} layer performed well as a diffusion barrier against Se and the thickness of MoSe{sub 2} can be controlled precisely by adjusting the top Mo layer thickness. Furthermore, TEM and energy dispersive spectroscopy analysis showed that the selenized multilayer consisted of MoSe{sub 2}/Mo/MoN{sub x}/Mo, in which the top Mo layer of 60 nm was not fully converted to MoSe{sub 2} and 20 nm was left unreacted. The residual Mo interlayer located at the interface of MoSe{sub 2} and MoN{sub x} is believed to be beneficial for the ohmic contact of the selenized multilayer.

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

    Directory of Open Access Journals (Sweden)

    Augustyn-Pieniążek J.

    2015-09-01

    Full Text Available 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 mass decrement were minimal, which proved a high abrasive wear resistance.

  11. Computation of beam quality parameters for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations in mammography

    International Nuclear Information System (INIS)

    Kharrati, Hedi; Zarrad, Boubaker

    2003-01-01

    A computer program was implemented to predict mammography x-ray beam parameters in the range 20-40 kV for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations. The computation method used to simulate mammography x-ray spectra is based on the Boone et al. model. The beam quality parameters such as the half-value layer (HVL), the homogeneity coefficient (HC), and the average photon energy were computed by simulating the interaction of the spectrum photons with matter. The checking of this computation was done using a comparison of the results with published data and measured values obtained at the Netherlands Metrology Institute Van Swinden Laboratorium, National Institute of Standards and Technology, and International Atomic Energy Agency. The predicted values with a mean deviation of 3.3% of HVL, 3.7% of HC, and 1.5% of average photon energy show acceptable agreement with published data and measurements for all target/filter combinations in the 23-40 kV range. The accuracy of this computation can be considered clinically acceptable and can allow an appreciable estimation for the beam quality parameters

  12. 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

  13. Irradiation performance of U-Mo monolithic fuel

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, M. K.; Gan, J.; Jue, J. F.; Keiser, D. D.; Perez, E.; Robinson, A.; Wachs, D. M.; Woolstenhulme, N. [Idaho National Laboratory, Idaho (Korea, Republic of); Kim, Y.S.; Hofman, G. L. [Argonne National Laboratory, Lemont (United States)

    2014-04-15

    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. U-Mo 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.

  14. 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

  15. Surface science models of CoMoS hydrodesulfurisation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    De Jong, A.M.; De Beer, V.H.J.; Van Veen, J.A.R.; Niemantsverdriet, J.W. [Schuit Institute of Catalysis, Eindhoven University of Technology, Eindhoven (Netherlands)

    1997-07-01

    Characterization of supported catalysts with surface spectroscopic techniques is often limited due to restraints imposed by the support material. The use of flat conducting substrates as a model support offers a way to apply these techniques to their full potential. Such surface science models of silica and alumina supported CoMoS catalysts have been made by impregnating thin SiO{sub 2} and Al{sub 2}O{sub 3} films with a solution of nitrilotriacetic acid (NTA) complexes of cobalt and molybdenum. X-ray Photoelectron Spectroscopy (XPS) spectra indicate that the order in which cobalt and molybdenum transfer to the sulfided state is reversed with respect to oxidic Co and Mo systems prepared by conventional methods, implying that NTA complexation retards the sulfidation of cobalt to temperatures where MoS{sub 2} is already formed. Catalytic tests show that the CoMoS model catalysts exhibit activities for thiophene desulfurisation and product distributions similar to those of their high surface area counterparts. 25 refs.

  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. Exploring Neutron-Rich Oxygen Isotopes with MoNA

    International Nuclear Information System (INIS)

    Frank, N.; Gade, A.; Peters, W. A.; Thoennessen, M.; Baumann, T.; Bazin, D.; Lecouey, J.-L.; Scheit, H.; Schiller, A.; Brown, J.; DeYoung, P. A.; Finck, J. E.; Hinnefeld, J.; Howes, R.; Luther, B.

    2007-01-01

    The Modular Neutron Array (MoNA) was used in conjunction with a large-gap dipole magnet (Sweeper) to measure neutron-unbound states in oxygen isotopes close to the neutron dripline. While no excited states were observed in 24 O, a resonance at 45(2) keV above the neutron separation energy was observed in 23 O

  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. Fission product induced swelling of U–Mo alloy fuel

    International Nuclear Information System (INIS)

    Kim, Yeon Soo; Hofman, G.L.

    2011-01-01

    Highlights: ► We measured fuel swelling of U–Mo alloy by fission products at temperatures below 250 °C. ► We quantified the swelling portion of U–Mo by fission gas bubbles. ► We developed an empirical model as a function of fission density. - Abstract: Fuel swelling of U–Mo alloy was modeled using the measured data from samples irradiated up to a fission density of ∼7 × 10 27 fissions/m 3 at temperatures below ∼250 °C. The overall fuel swelling was measured from U–Mo foils with as-fabricated thickness of 250 μm. Volume fractions occupied by fission gas bubbles were measured and fuel swelling caused by the fission gas bubbles was quantified. The portion of fuel swelling by solid fission products including solid and liquid fission products as well as fission gas atoms not enclosed in the fission gas bubbles is estimated by subtracting the portion of fuel swelling by gas bubbles from the overall fuel swelling. Empirical correlations for overall fuel swelling, swelling by gas bubbles, and swelling by solid fission products were obtained in terms of fission density.

  20. 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 ...

  1. Surface hardness behaviour of Ti–Al–Mo alloys

    Indian Academy of Sciences (India)

    Wintec

    Such a report is lacking in literature in this class of alloys. Keywords. Ti–Al–Mo alloys; microhardness; slip steps. 1. Introduction. Ti-aluminides containing α2 and γ phases with lamellar morphology are expected to possess hardness that is higher than the β and γ phases (Li and Loretto 1994). Room temperature ductility is ...

  2. RERTR progress in Mo-99 production from LEU

    Energy Technology Data Exchange (ETDEWEB)

    Vandegrift, G.F.; Conner, C.; Aase, S.; Bakel, A.; Bowers, D.; Freiberg, E.; Gelis, A.; Quigley, K.J.; Snelgrove, J.L. [Argonne National Laboratory 9700 S. Cass Avenue, Argonne, IL (United States)

    2002-07-01

    The ANL RERTR program is performing R and D supporting conversion of {sup 99}Mo production from HEU to LEU targets. Irradiation and processing of LEU targets were demonstrated at the Argentine Ezeiza Atomic Center. Target irradiation and disassembly were flawless, but the processing is not fully developed. In addition to preparing for, assisting in, and analyzing results of the demonstration, we performed other R and D related to LEU conversion: (1) designing a prototype production dissolver for digesting irradiated LEU foils in alkaline solutions and developing means to simplify digestion, (2) modifying ion-exchange columns used in the CNEA recovery and purification of {sup 99}Mo to deal with the lower volumes generated from LEU-foil digestion, (3) measuring the performance of new inorganic sorbents that outperform alumina for recovering Mo(VI) from nitric acid solutions containing high concentrations of uranium nitrate, and (4) developing means to facilitate the concentration and calcination of waste nitric-acid/LEU-nitrate solutions from {sup 99} Mo production. (author)

  3. 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.

  4. Management of radioactive waste from 99Mo production

    International Nuclear Information System (INIS)

    1998-11-01

    99m Tc used for labelling different pharmaceuticals is the most important radionuclide in nuclear medicine practice, and probably will continue to play this important role for the foreseeable future. 99m Tc is the short lived daughter product of the parent 99 Mo, which is mainly produced by the nuclear fission of 235 U. Recognizing the importance of the waste management issue associated with 99 Mo production the IAEA initiated preparation of this report to provide Member States and existing and potential producers of 99 Mo with practical approaches and the available information on the subject. Waste management in the context of this report encompasses all waste-related aspects, for example, handling, treatment, conditioning, storage, transport, and disposal. The document is organized in several chapters giving the following information: short description of the basic nuclear and physical properties of 99 Mo and 99m Tc; an overview of past, present and possible future production methods; characteristics of the various waste streams produced in the aforementioned processes; description of the necessary waste management practices needed to handle the relevant waste streams in a responsible and internationally-accepted manner; conclusion and recommendations

  5. Interface Structure of MoO3 on Organic Semiconductors

    Science.gov (United States)

    White, Robin T.; Thibau, Emmanuel S.; Lu, Zheng-Hong

    2016-01-01

    We have systematically studied interface structure formed by vapor-phase deposition of typical transition metal oxide MoO3 on organic semiconductors. Eight organic hole transport materials have been used in this study. Ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy are used to measure the evolution of the physical, chemical and electronic structure of the interfaces at various stages of MoO3 deposition on these organic semiconductor surfaces. For the interface physical structure, it is found that MoO3 diffuses into the underlying organic layer, exhibiting a trend of increasing diffusion with decreasing molecular molar mass. For the interface chemical structure, new carbon and molybdenum core-level states are observed, as a result of interfacial electron transfer from organic semiconductor to MoO3. For the interface electronic structure, energy level alignment is observed in agreement with the universal energy level alignment rule of molecules on metal oxides, despite deposition order inversion. PMID:26880185

  6. Characterization of Mo/Si multilayer growth on stepped topographies

    NARCIS (Netherlands)

    van den Boogaard, Toine; Louis, Eric; Zoethout, E.; Goldberg, K.A.; Bijkerk, Frederik

    2011-01-01

    Mo/Si multilayer mirrors with nanoscale bilayer thicknesses have been deposited on stepped substrate topographies, using various deposition angles. The multilayer morphology at the step-edge region was studied by cross section transmission electron microscopy. A transition from a continuous- to

  7. Electrical resistivity of liquid Ti, V, Mo and W

    International Nuclear Information System (INIS)

    Seydel, U.; Fucke, W.

    1980-01-01

    Electrical resistivity data for liquid Ti, V, Mo and W in the temperature range from melting to boiling are presented. The data were obtained by a fast resistive pulse heating technique based on heating small samples shaped as wires or foils in an RCL discharge circuit and simultaneously measuring temperature, volume, voltage and current. (author)

  8. Iridium Sulfide and Ir Promoted Mo Based Catalysts.

    Czech Academy of Sciences Publication Activity Database

    Vít, Zdeněk

    2007-01-01

    Roč. 322, - (2007), s. 142-151 ISSN 0926-860X R&D Projects: GA ČR(CZ) GA104/06/0870 Institutional research plan: CEZ:AV0Z40720504 Keywords : iridium sulfide * IrMo catalyst * hydrodesulfurization Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.166, year: 2007

  9. Magnetoresistance in molybdenite (MoS2) crystals

    International Nuclear Information System (INIS)

    Chakraborty, B.R.; Dutta, A.K.

    1975-01-01

    The principal magnetoresistance ratios of molybdenite (MoS 2 ), the naturally occurring semiconducting crystal, have been investigated at magnetic fields ranging from 4.5 KOe and within the temperature range 300 0 K to 700 0 K. Unlike some previous observations, magnetoresistance has been found to be negative. (author)

  10. Atomic displacements in dilute alloys of Cr, Nb and Mo

    Indian Academy of Sciences (India)

    physics pp. 497–514. Atomic displacements in dilute alloys of Cr, Nb and Mo ... used to calculate dynamical matrix and the impurity-induced forces up to second nearest ... origin, the lattice is strained, and the host atoms get displaced to new ...

  11. 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)

  12. 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

  13. Network Coded Software Defined Networking

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...

  14. 99Mo production for using in the nuclear medicine in 99mTc generators

    International Nuclear Information System (INIS)

    Kurenkov, N.V.; Chuvilin, D.Yu.

    1999-01-01

    The review of methods and advanced technologies for obtaining 99 Mo in nuclear reactors is presented. The 99 Mo isotope is used for preparing the 99m Tc generators, widely applied in nuclear medicine. The reactor method for obtaining 99 Mo is based on the 98 Mo(n, γ) 99 Mo radiation capture reaction and 235 U fission reaction under the effect of the 235 U (n, f) 99 Mo reaction. The results of studies on obtaining 99 Mo on the charged particles accelerators, mainly, on the proton beam and under the effect of photonuclear reaction is also described. The data on the 99 Mo real consumption and forecast for its application in different regions of the world from 1994 up to 2006 are presented [ru

  15. 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

  16. Formation of Ni(Al, Mo) solid solutions by mechanical alloying and their ordering on heating

    International Nuclear Information System (INIS)

    Portnoj, V.K.; Tomilin, I.A.; Blinov, A.M.; Kulik, T.

    2002-01-01

    The Ni(Al, Mo) solid solutions with different crystalline lattice periods (0.3592 and 0.3570 nm correspondingly) are formed in the course of the Ni 70 Al 25 Mo 5 and Ni 75 Al 20 Mo 5 powder mixtures mechanical alloying (MA) (through the mechanical activation in a vibrating mill). After MA the Mo atoms in the Ni 75 Al 20 Mo 5 mixture completely replace the aluminium positions with formation of the Ni 75 (AlMo) 25 (the L1 2 -type) ternary ordered phase, whereby such a distribution remains after heating up to 700 deg C. The Ni(Al, Mo) metastable solution is formed by MA in the Ni 75 Al 20 Mo 5 mixture, which decays with the release of molybdenum and the remained aluminide undergoes ordering by the L1 2 -type [ru

  17. Recycling 100Mo for direct production of 99mTc on medical cyclotrons

    Science.gov (United States)

    Kumlin, Joel O.; Zeisler, Stefan K.; Hanemaayer, Victoire; Schaffer, Paul

    2018-05-01

    A scalable recycling technique for the recovery of 100Mo from previously irradiated and chemically processed targets is described. A combined process for both Cu and Ta supported targets and the respective `waste' solutions has been developed. This process involves selectively dissolving Cu target backings from undissolved portions of 100Mo pellets; precipitating Cu(OH)2 at pH 9; electrochemical removal of Cu traces; precipitating (NH4)2MoO4 at pH 2.5-3; thermally decomposing (NH4)2MoO4; and H2 reduction of MoO3 to Mo metal. Radionuclidic decontamination by a factor of 100 is observed, while overall 100Mo recovery from initial target plating to recycled Mo metal of 96% is achieved.

  18. Structure of glasses of the TeO2-MoO3 system

    International Nuclear Information System (INIS)

    Dimitriev, Y.; Dimitrov, V.; Bart, J.C.J.

    1981-01-01

    Structural models for glasses of the TeO 2 -MoO 3 system are suggested. On the basis of X-ray and infrared spectral investigations, by comparing with known crystalline structures of TeO 2 , MoO 3 and Te 2 MoO 7 9t 2 M, it is shown that the glasses from TeO 2 to Te 2 MoO 7 possess [TeO 4 ] and [MoO 5 ] groups as basic structural units. The latter are connected to form [Mo 2 O 8 ] complexes. The glasses in the MoO 3 -rich compositional range are built up of [TeO 3 ] and [MoO 6 ] polyhedra. The glass-formation tendency is discussed in relation to the role of the free electron pair and the disruption of secondary and weak primary bonds in the crystals. (author)

  19. 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.

  20. Measurement of the molar heat capacities of MoO2 and MoO3 from 350 to 950 K

    International Nuclear Information System (INIS)

    Inaba, H.; Miyahara, K.; Naito, K.

    1984-01-01

    Molar heat capacities of MoO 2 and MoO 3 were measured in the range between 350 and 950 K by means of adiabatic scanning calorimetry. For MoO 2 , a sharp heat-capacity anomaly with a molar enthalpy change of (178 +- 24) J.mol -1 and a molar entropy change of (0.207 +- 0.028) J.K -1 .mol -1 was observed at 865 K, which had not been detected by drop calorimetry. For MoO 3 , two heat-capacity anomalies with molar enthalpy changes of (88 +- 21) and (60 +- 36) J.mol -1 were found at 808 K and 857 K, respectively; neither anomaly had been detected by the drop method. The lattice molar heat capacities of MoO 2 and MoO 3 are estimated as Csub(l,m)(MoO 2 ) = D(469 K/T) + E(578 K/T) + E(876 K/T) and Csub(l,m)(MoO 3 ) = D(208 K/T) + 2E(488 K/T) + E(1170 K/T), where D(x) and E(x) are the Debye and Einstein functions, respectively. The temperature coefficient of the electronic molar heat capacity of MoO 2 is estimated as (6.0 +- 0.5) mJ.K -2 .mol -1 . The excess heat capacity in MoO 3 found at higher temperatures is interpreted as being due to vacancy formation with a molar activation energy of (98 +-5) kJ.mol -1 . The origin of the heat-capacity anomalies is inferred as arising from the slight movement of distorted MoO 6 octahedra in the MoO 2 and MoO 3 structures. (author)

  1. Observation of Vacancies, Faults, and Superstructures in Ln5Mo2O12 (Ln = La, Y, and Lu) Compounds with Direct Mo-Mo Bonding.

    Science.gov (United States)

    Colabello, Diane M; Sobalvarro, Elizabeth M; Sheckelton, John P; Neuefeind, Joerg C; McQueen, Tyrel M; Khalifah, Peter G

    2017-11-06

    Among oxide compounds with direct metal-metal bonding, the Y 5 Mo 2 O 12 (A 5 B 2 O 12 ) structural family of compounds has a particularly intriguing low-dimensional structure due to the presence of bioctahedral B 2 O 10 dimers arranged in one-dimensional edge-sharing chains along the direction of the metal-metal bonds. Furthermore, these compounds can have a local magnetic moment due to the noninteger oxidation state (+4.5) of the transition metal, in contrast to the conspicuous lack of a local moment that is commonly observed when oxide compounds with direct metal-metal bonding have integer oxidation states resulting from the lifting of orbital degeneracy typically induced by the metal-metal bonding. Although a monoclinic C2/m structure has been previously proposed for Ln 5 Mo 2 O 12 (Ln = La-Lu and Y) members of this family based on prior single crystal diffraction data, it is found that this structural model misses many important structural features. On the basis of synchrotron powder diffraction data, it is shown that the C2/m monoclinic unit cell represents a superstructure relative to a previously unrecognized orthorhombic Immm subcell and that the superstructure derives from the ordering of interchangeable Mo 2 O 10 and LaO 6 building blocks. The superstructure for this reason is typically highly faulted, as evidenced by the increased breadth of superstructure diffraction peaks associated with a coherence length of 1-2 nm in the c* direction. Finally, it is shown that oxygen vacancies can occur when Ln = La, producing an oxygen deficient stoichiometry of La 5 Mo 2 O 11.55 and an approximately 10-fold reduction in the number of unpaired electrons due to the reduction of the average Mo valence from +4.5 to +4.05, a result confirmed by magnetic susceptibility measurements. This represents the first observation of oxygen vacancies in this family of compounds and provides an important means of continuously tuning the magnetic interactions within the one

  2. 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.

  3. Systems Tl2MoO4-E(MoO4)2, where E=Zr or Hf, and the crystal structure of Tl8Hf(MoO4)6

    International Nuclear Information System (INIS)

    Bazarov, B.G.; Bazarova, Ts.T.; Fedorov, K.N.; Bazarova, Zh.G.; Chimitova, O.D.; Klevtsova, R.F.; Glinskaya, L.A.

    2006-01-01

    Systems Tl 2 MoO 4 -E(MoO 4 ) 2 (E=Zr, Hf) were studied by X-ray diffraction, differential thermal analysis and IR spectroscopy. Formation of Tl 8 E(MoO 4 ) 6 and Tl 2 E(MoO 4 ) 2 compounds was established. Phase T-x diagrams of the Tl 2 MoO 4 -Zr(MoO 4 ) 2 system were constructed. Monocrystals were grown, and structure of Tl 8 Hf(MoO 4 ) 6 was studied. The compound is crystallized in monoclinic syngony with elementary cell parameters a=9.9688(6), b=18.830(1), c=7.8488(5) A, β=108.538(1) Deg, Z=2, sp. gr. C2/m. The isolated group [HfMo 6 O 24 ] 8- is responsible for fundamental fragment of the structure. Three varieties of crystallographically independent Tl-polyhedra fill space evenly between fragments [HfMo 6 O 24 ] 8- forming three-dimensional form [ru

  4. Nucleation of microwave plasma CVD diamond on molybdenum (Mo) substrate

    International Nuclear Information System (INIS)

    Inderjeet, K.; Ramesh, S.

    2000-01-01

    Molybdenum is a metal, which is gaining increasing significance in industrial applications. The main use of Mo is as all alloying element added in small amounts to steel, irons and non- ferrous alloys in order to enhance the strength, toughness and wear resistance. Mo is also vastly being employed in the automotive and aircraft industries, mainly due to its low coefficient of friction. Diamond, on be other hand, is a unique material for innumerable applications because of its usual combination of physical and chemical properties. Several potential applications can be anticipated for diamond in many sectors including electronics, optics, as protective corrosion resistant coatings, cutting tools, etc. With the enhancement in science and technology, diamond microcrystals and thin films are now being produced from the vapour phase by a variety of chemical vapour deposition (CVD) techniques; such as microwave plasma CVD. With such technology being made available, it is envisage that diamond-coated molybdenum would further enhance the performance and to open up new avenue for Mo in various industries. Therefore, it is the aim of the present work to study the nucleation and growth of diamond particles on Mo surface by employing microwave plasma CVD (MAPCVD). In the present work, diamond deposition was carried out in several stages by varying the deposition distance. The nucleation and growth rate were studied using scanning electron microscopy (SEM). In addition, the existence of diamond was verified by X-ray diffraction (XRD) analysis. It has been found that the nucleation and growth rate of diamond particles were influenced by the deposition height between the substrate and plasma. Under the optimum condition, well defined diamond crystallites distributed homogeneously throughout the surface, could be obtained. Some of the important parameters controlling the deposition and growth of diamond particles on Mo surface are discussed. (author)

  5. Magnetothermopower in A2−xLaxFeMoO6 (A = Sr, Ba

    Directory of Open Access Journals (Sweden)

    G. V. M. Williams

    2017-01-01

    Full Text Available A magnetothermopower has been observed in electronically spin-polarized polycrystalline Sr2-xLaxFeMoO6 and Ba2FeMoO6. The magnetothermopower is linear up to ~50 K for Sr2-xLaxFeMoO6 and linear up to ~270 K for Ba2FeMoO6. We suggest that the magnetothermopower may arise from a spin-tunneling magnetothermopower between the grains.

  6. 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.

  7. Networked Identities

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Larsen, Malene Charlotte

    2008-01-01

    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......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...... argue that understanding meaning-making and ‘networked identities’ may be relevant analytic entry points in navigating the challenges....

  8. 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)

  9. 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.

  10. Effect of monoclonal antibodies (MoAb) to class I and class II HLA antigens on lectin- and MoAb OKT3-induced lymphocyte proliferation.

    Science.gov (United States)

    Akiyama, Y; Zicht, R; Ferrone, S; Bonnard, G D; Herberman, R B

    1985-04-01

    We have examined the effect of several monoclonal antibodies (MoAb) to monomorphic determinants of class II HLA antigens, and MoAb to monomorphic determinants of class I HLA antigens and to beta-2-microglobulin (beta 2-mu) on lectin- and MoAb OKT3-induced proliferation of human peripheral blood mononuclear cells (PBMNC) and cultured T cells (CTC). Some, but not all, anti-class II HLA MoAb inhibited the proliferative response of PBMNC to MoAb OKT3 and pokeweed mitogen (PWM). The degree of inhibitory effect varied considerably. This effect was not limited to anti-class II HLA MoAb since anti-class I HLA MoAb and anti-beta 2-mu MoAb also inhibited MoAb OKT3- or PWM-induced proliferative responses. In contrast, the response of PBMNC to phytohemagglutinin (PHA) and concanavalin A (Con A) was not blocked by any anti-class II HLA MoAb. However, some anti-class II HLA MoAb also inhibited the proliferative response of CTC plus allogeneic peripheral blood adherent accessory cells (AC) to PHA or Con A as well as to MoAb OKT3 or PWM. This may be attributable to the substantially greater class II HLA antigen expression by CTC than by fresh lymphocytes. Pretreatment of either CTC or AC with anti-class II HLA MoAb inhibited OKT3-induced proliferation. In contrast, pretreatment of CTC, but not AC, with anti-class I HLA MoAb inhibited the proliferative response of CTC to OKT3. Pretreatment of CTC with anti-class I HLA MoAb inhibited PHA-, Con A and PWM-induced proliferation, to a greater degree than the anti-class II HLA MoAb. It appears as if lymphocyte activation by different mitogens exhibits variable requirements for the presence of cells expressing major histocompatibility determinants. Binding of Ab to membrane markers may interfere with lymphocyte-AC cooperation, perhaps by inhibiting binding of mitogens to their receptors or by interfering with lymphocyte and AC function. We also have examined the role of class II HLA antigens on CTC by depleting class II HLA-positive cells

  11. Construction of Hierarchical CNT/rGO-Supported MnMoO4 Nanosheets on Ni Foam for High-Performance Aqueous Hybrid Supercapacitors.

    Science.gov (United States)

    Mu, Xuemei; Du, Jingwei; Zhang, Yaxiong; Liang, Zhilin; Wang, Huan; Huang, Baoyu; Zhou, Jinyuan; Pan, Xiaojun; Zhang, Zhenxing; Xie, Erqing

    2017-10-18

    Rationally designed conductive hierarchical nanostructures are highly desirable for supporting pseudocapacitive materials to achieve high-performance electrodes for supercapacitors. Herein, manganese molybdate nanosheets were hydrothermally grown with graphene oxide (GO) on three-dimensional nickel foam-supported carbon nanotube structures. Under the optimal graphene oxide concentration, the obtained carbon nanotubes/reduced graphene oxide/MnMoO 4 composites (CNT/rGO/MnMoO 4 ) as binder-free supercapacitor cathodes perform with a high specific capacitance of 2374.9 F g -1 at the scan rate of 2 mV s -1 and good long-term stability (97.1% of the initial specific capacitance can be maintained after 3000 charge/discharge cycles). The asymmetric device with CNT/rGO/MnMoO 4 as the cathode electrode and the carbon nanotubes/activated carbon on nickel foam (CNT-AC) as the anode electrode can deliver an energy density of 59.4 Wh kg -1 at the power density of 1367.9 W kg -1 . These superior performances can be attributed to the synergistic effects from each component of the composite electrodes: highly pseudocapacitive MnMoO 4 nanosheets and three-dimensional conductive Ni foam/CNTs/rGO networks. These results suggest that the fabricated asymmetric supercapacitor can be a promising candidate for energy storage devices.

  12. Synthesis of MoO 3 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.

  13. 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.

  14. 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

  15. Oxidation of atomically thin MoS2 on SiO2

    Science.gov (United States)

    Yamamoto, Mahito; Cullen, William; Einstein, Theodore; Fuhrer, Michael

    2013-03-01

    Surface oxidation of MoS2 markedly affects its electronic, optical, and tribological properties. However, oxidative reactivity of atomically thin MoS2 has yet to be addressed. Here, we investigate oxidation of atomic layers of MoS2 using atomic force microscopy and Raman spectroscopy. MoS2 is mechanically exfoliated onto SiO2 and oxidized in Ar/O2 or Ar/O3 (ozone) at 100-450 °C. MoS2 is much more reactive to O2 than an analogous atomic membrane of graphene and monolayer MoS2 is completely etched very rapidly upon O2 treatment above 300 °C. Thicker MoS2 (> 15 nm) transforms into MoO3 after oxidation at 400 °C, which is confirmed by a Raman peak at 820 cm-1. However, few-layer MoS2 oxidized below 400 °C exhibits no MoO3 Raman mode but etch pits are formed, similar to graphene. We find atomic layers of MoS2 shows larger reactivity to O3 than to O2 and monolayer MoS2 transforms chemically upon O3 treatment even below 100 °C. Work supported by the U. of Maryland NSF-MRSEC under Grant No. DMR 05-20741.

  16. 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, ...

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

    KAUST Repository

    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

    2014-01-01

    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

  18. Phase formation in the Rb2MoO4-Li2MoO4-Hf(MoO4)2 system and the crystal structure of Rb5(Li1/3Hf5/3)(MoO4)6

    International Nuclear Information System (INIS)

    Solodovnikov, S.F.; Zolotova, E.S.; Balsanova, L.V.; Bazarov, B.G.; Bazarova, Zh.G.

    2003-01-01

    Phase formation in the Rb 2 MoO 4 -Li 2 MoO 4 -Hf(MoO 4 ) 2 system is studied in subsolidus region in air by the method of crossing sections. Three ternary molybdates are detected in the system. Compositions of two of them are corroborated by selection of isostructural analogues [ru

  19. Microstructure, mechanical property, corrosion behavior, and in vitro biocompatibility of Zr-Mo alloys.

    Science.gov (United States)

    Zhou, F Y; Wang, B L; Qiu, K J; Li, L; Lin, J P; Li, H F; Zheng, Y F

    2013-02-01

    In this study, the microstructure, mechanical properties, corrosion behaviors, and in vitro biocompatibility of Zr-Mo alloys as a function of Mo content after solution treatment were systemically investigated to assess their potential use in biomedical application. The experimental results indicated that Zr-1Mo alloy mainly consisted of an acicular structure of α' phase, while ω phase formed in Zr-3Mo alloy. In Zr-5Mo alloy, retained β phase and a small amount of precipitated α phase were observed. Only the retained β phase was obtained in Zr-10Mo alloy. Zr-1Mo alloy exhibited the greatest hardness, bending strength, and modulus among all experimental Zr-Mo alloys, while β phase Zr-10Mo alloy had a low modulus. The results of electrochemical corrosion indicated that adding Mo into Zr improved its corrosion resistance which resulted in increasing the thermodynamic stability and passivity of zirconium. The cytotoxicity test suggested that the extracts of the studied Zr-Mo alloys produced no significant deleterious effect to fibroblast cells (L-929) and osteoblast cells (MG 63), indicating an excellent in vitro biocompatibility. Based on these facts, certain Zr-Mo alloys potentially suitable for different biomedical applications were proposed. Copyright © 2012 Wiley Periodicals, Inc.

  20. MoOx modified ZnGaO based transparent conducting oxides

    Science.gov (United States)

    Dutta, Titas; Gupta, P.; Bhosle, V.; Narayan, J.

    2009-03-01

    We report here the growth of high work function bilayered structures of thin MoOx (2.0MoOx layer, molybdenum exists in Mo4+, Mo5+, and Mo6+ oxidation states, and the ratio of (Mo4++Mo5+) to Mo6+ was determined to be ˜2:1. The bilayer films showed good optical transparency (≥80%) and low resistivity of ˜10-4 Ω cm. Different transport behavior of the MoOx/ZnGa0.05O films grown at different Ts (substrate temperature) was observed in temperature-dependent resistivity measurements. The bilayer film at higher Ts showed metallic conductivity behavior down to 113 K. Moreover, a blueshift of the absorption edge in the transmission spectrum was observed with the increase in Ts, indicating an increase in the carrier concentration. It was observed that the ZnGa0.05O films with ultrathin MoOx (˜1-2 nanometers) overlayer showed a higher work function (varying from 4.7 to 5.1 eV) as compared to the single layer ZnGa0.05O film work function (˜4.4 eV). A correlation between the surface work function and MoOx layer thickness is observed. The higher work function of the MoOx overlayer is envisaged to improve the transport of the carriers across the heterojunction in a solid state device, thus resulting an increase in device efficiency.

  1. 76 FR 28685 - Proposed Amendment of Class E Airspace; Hannibal, MO

    Science.gov (United States)

    2011-05-18

    ...-0046; Airspace Docket No. 11-ACE-1] 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...

  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. Single cyanide-bridged Mo(W)/S/Cu cluster-based coordination polymers: Reactant- and stoichiometry-dependent syntheses, effective photocatalytic properties

    International Nuclear Information System (INIS)

    Zhang, Jinfang; Wang, Chao; Wang, Yinlin; Chen, Weitao; Cifuentes, Marie P.; Humphrey, Mark G.; Zhang, Chi

    2015-01-01

    The systematic study on the reaction variables affecting single cyanide-bridged Mo(W)/S/Cu cluster-based coordination polymers (CPs) is firstly demonstrated. Five anionic single cyanide-bridged Mo(W)/S/Cu cluster-based CPs {[Pr_4N][WS_4Cu_3(CN)_2]}_n (1), {[Pr_4N][WS_4Cu_4(CN)_3]}_n (2), {[Pr_4N][WOS_3Cu_3(CN)_2]}_n (3), {[Bu_4N][WOS_3Cu_3(CN)_2]}_n (4) and {[Bu_4N][MoOS_3Cu_3(CN)_2]}_n (5) were prepared by varying the molar ratios of the starting materials, and the specific cations, cluster building blocks and central metal atoms in the cluster building blocks. 1 possesses an anionic 3D diamondoid framework constructed from 4-connected T-shaped clusters [WS_4Cu_3]"+ and single CN"− bridges. 2 is fabricated from 6-connected planar ‘open’ clusters [WS_4Cu_4]"2"+ and single CN"− bridges, forming an anionic 3D architecture with an “ACS” topology. 3 and 4 exhibit novel anionic 2-D double-layer networks, both constructed from nest-shaped clusters [WOS_3Cu_3]"+ linked by single CN"− bridges, but containing the different cations [Pr_4N]"+ and [Bu_4N]"+, respectively. 5 is constructed from nest-shaped clusters [MoOS_3Cu_3]"+ and single CN"− bridges, with an anionic 3D diamondoid framework. The anionic frameworks of 1-5, all sustained by single CN"− bridges, are non-interpenetrating and exhibit huge potential void volumes. Employing differing molar ratios of the reactants and varying the cluster building blocks resulted in differing single cyanide-bridged Mo(W)/S/Cu cluster-based CPs, while replacing the cation ([Pr_4N]"+ vs. [Bu_4N]"+) was found to have negligible impact on the nature of the architecture. Unexpectedly, replacement of the central metal atom (W vs. Mo) in the cluster building blocks had a pronounced effect on the framework. Furthermore, the photocatalytic activities of heterothiometallic cluster-based CPs were firstly explored by monitoring the photodegradation of methylene blue (MB) under visible light irradiation, which reveals that 2

  4. 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

  5. Network cohesion

    OpenAIRE

    Cavalcanti, Tiago V. V.; Giannitsarou, Chryssi; Johnson, Charles R.

    2016-01-01

    This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s00199-016-0992-1 We define a measure of network cohesion and show how it arises naturally in a broad class of dynamic models of endogenous perpetual growth with network externalities. Via a standard growth model, we show why network cohesion is crucial for conditional convergence and explain that as cohesion increases, convergence is faster. We prove properties of network cohesion and d...

  6. 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

  7. 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

  8. Double molybdates in Li2MoO4 - Na2MoO4 - H2O system at 25 grad C

    International Nuclear Information System (INIS)

    Karov, Z.G.; Mirzoev, R.S.; Makitova, D.D.; Zhilova, S.B.; Podnek, A.G.; Urusova, R.Kh.

    1989-01-01

    Solubility in Li 2 MoO 4 - Na 2 MoO 4 - H 2 O system at 25 deg C is first stuied. Formation of two Li 2 MoO 4 · Na 2 MoO 4 · 4H 2 O and Li 2 MoO 4 · 3Na 2 MoO 4 · 12H 2 O compounds in a system is ascertained. Density, refractive index, viscosity, surface tension, electric conductivity and pH of saturated solutions are determined. Isothermes of mole volume, equivalent and reduced electric conductivity and seeming mole volume of salts sum in solutions are calculated. All these properties adequtely confirm the character of components interaction in a system determined by solubility method. Crystallhydrates of binary molybdates are separated, indentified and studied

  9. Absorption spectra of CsNd(MoO4)2 and CsGd(MoO4)2-Nd3+ crystals in strong magnetic fields

    International Nuclear Information System (INIS)

    Gorban', I.S.; Kozeeva, L.P.; Slobodyanyuk, A.V.; Shevchenko, V.A.

    1987-01-01

    The comparison of the electronic structure of Nd 3+ in CsNd(MoO 4 ) 2 and CsGd(MoO 4 ) 2 - Nd 3+ crystals is made. It is established that in these crystals the activator centers, mainly, of the certain type with the symmetry of the local environment C 2 are formed. The absorption spectra of self-activated CsNd(MoO 4 ) 2 crystal differ from spectra of CsGd(MoO 4 ) 2 - Nd 3+ by the presence of the vibrating structure. The Stark splittings of energy levels of Nd 3+ in the investigated crystalline matrices are more sensitive to the environment effect than the Zeeman ones. The ground state of Nd 3+ ion in CsNd(MoO 4 ) 2 and CsGd(MoO 4 ) 2 molybdates is characterized by the similar values of g-factors

  10. X-ray and electron microscopy investigation of the topotactic transformation of MoO3 into MoO2

    International Nuclear Information System (INIS)

    Bertrand, O.; Dufour, L.C.

    1980-01-01

    The reduction of MoO 3 is investigated by X-ray analysis and electron microscopy from MoO 3 (010) platelets between 1000 A and 5 mm long. In all cases, the following orientation relationship between both lattices is found: [100] 2 parallel [010] 3 , [122] 2 parallel [100] 3 . [-12-2] 2 parallel [001] 3 . MoO 3 crystallites twinning and misorientation are discussed in relation with the particular importance of [101] 3 directions in MoO 3 preserved in the transformation and becoming [010] 2 of MoO 2 . A model for this topotactic reduction is proposed where the reaction develops layer (010) 3 by layer (010) 3 to form [20-1] 2 type planes in MoO 2 structure. Data on the kinetics of the boundary moving in [010] 3 direction are also presented. (author)

  11. Electronic structure investigation of MoS2 and MoSe2 using angle-resolved photoemission spectroscopy and ab initio band structure studies.

    Science.gov (United States)

    Mahatha, S K; Patel, K D; Menon, Krishnakumar S R

    2012-11-28

    Angle-resolved photoemission spectroscopy (ARPES) and ab initio band structure calculations have been used to study the detailed valence band structure of molybdenite, MoS(2) and MoSe(2). The experimental band structure obtained from ARPES has been found to be in good agreement with the theoretical calculations performed using the linear augmented plane wave (LAPW) method. In going from MoS(2) to MoSe(2), the dispersion of the valence bands decreases along both k(parallel) and k(perpendicular), revealing the increased two-dimensional character which is attributed to the increasing interlayer distance or c/a ratio in these compounds. The width of the valence band and the band gap are also found to decrease, whereas the valence band maxima shift towards the higher binding energy from MoS(2) to MoSe(2).

  12. Preparation of 99Mo/99mTc generators based on 99Mo zirconium molybdates in the Gel Synthesis Device for Generators

    International Nuclear Information System (INIS)

    Lopez M, I. Z.; Monroy G, F.; Rivero G, T.; Rojas N, P.

    2008-01-01

    The 99m Tc is used for diagnosis and therapy. It is produced commercially from 99 Mo obtained from the fission of 235 U, which is retained in chromatographic columns filled with alumina whose maximum capacity is 0.2%. Given these constraints new methods of preparation 99 Mo/ 99m Tc generators have been developed using zirconium molybdates gels containing up to 30% of Mo, which is part of the generator matrix, and retaining quality and purity similar characteristics to those commercial generators. The present study aims to determine the flow of agitation, temperature and drying time optimal to prepare 99 Mo/ 99m Tc generators based on 99 Mo zirconium molybdates in the Gel Synthesis Device 99 Mo/ 99m Tc Generators designed and built by groups of the Radioactive Materials Research Laboratory and Automation and Instrumentation Department of the National Institute of Nuclear Research. (Author)

  13. Hydrotreatment of 8-hydroxyquinoline on a NiMo/Al sub 2 O sub 3 catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.M.; Satterfield, C.N. (Massachusetts Institute of Technology, Cambridge, MA (USA). Dept. of Chemical Engineering)

    The hydrotreatment of 8-hydroxyquinoline was studied on a sulfided NiMo/Al{sub 2}O{sub 3} catalyst at 360{degree}C and 6.9 MPa total pressure of H{sub 2} in a vapour-phase tubular reactor. Some minor studies were performed at 385{degree}C. 8-Hydroxyquinoline undergoes hydrodeoxygenation via three routes to enter the hydrodenitrogenation network of quinoline. Route 1 is hydrogenation of the heterocyclic ring to 8-hydroxy-1,2,3,4-tetrahydroquinoline (8HTHQ) followed by hydrogenation of the aromatic ring to 8-hydroxydecahydroquinoline which undergoes C-O hydrogenolysis to decahydroquinoline. Route 2 is direct C-O hydrogenolysis of 8HTHQ to form 1,2,3,4-tetrahydroquinoline (PyTHQ). Route 3 is hydrogenation of the benzene ring in 8-hydroxyquinoline to form 8-hydroxy-5,6,7,8-tetrahydroquinoline followed by removal of the oxygen to form 5,6,7,8-tetrahydroquinoline. After oxygen removal, subsequent reactions follow the hydrodenitrogenation network of quinoline. The hydroconversion of 8-hydroxyquinoline is governed by the N center rather than the OH center. 14 refs., 9 figs.

  14. 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.

  15. Analysis of steady-state creep of Fe-Mo alloys from the viewpoint of recovery

    International Nuclear Information System (INIS)

    Maruyama, K.; Karashima, S.; Oikawa, H.

    1979-01-01

    A theoretical equation to d evaluate the steady-state creep-rates, d epsilon/dtsub(s), based on a recovery creep model is derived: epsilonsub(s)/dt proportional to r/sigma 2 sub(a) x lambda 2 , where r is the recovery rate, which can be determined from results of stress-reduction tests, deltasub(a) the applied stress, and lambda the dislocation link-length. Two cases of recovery are considered, i.e., recovery of dislocation networks at sub-boundaries and that of three-dimensional networks within subgrains. The high-temperature steady-state creep of Fe-Mo solid solutions, creep characteristics of which have been reported to be well rationalized as viscous glide creep, is analyzed using this equation. It is shown that stress dependence of d epsilon/dtsub(s) is well explained from the viewpoint of recovery, in which the activation and the annihilation of dislocations at sub-boundaries are considered to take place. (orig.) [de

  16. 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.

  17. Full article: The Reaction between MoO3 and Molten K2S2O7 forming K2MoO2(SO4)2

    DEFF Research Database (Denmark)

    Nørbygaard, Thomas; Berg, Rolf W.; Nielsen, Kurt

    1998-01-01

    .4540(4), c = 8.8874(3) Å, beta = 112.194(1)o, wR2 = 0.0897 for 3491 independent reflections. The compound, K2MoO2(SO4)2, contains (Mo02)2+ core ions in distorted octahedral coordination, with two short (ca. 1.69 Å) terminal bonds in cis-configuration (the O-Mo-O angle is 103.1(2)o), and with two long (ca. 2...

  18. First-principles study on the structural, cohesive and electronic properties of rhombohedral Mo2B5 as compared with hexagonal MoB2

    International Nuclear Information System (INIS)

    Shein, I.R.; Shein, K.I.; Ivanovskii, A.L.

    2007-01-01

    The full-potential linearized augmented plane wave method using the generalized gradient approximation (FLAPW-GGA) has been applied to provide comparison and contrast for Mo borides with various structural types: rhombohedral Mo 2 B 5 versus hexagonal MoB 2 . The equilibrium lattice parameters, energies of formations, total and partial densities of states, electronic density distributions and the theoretical shapes of boron K-edge X-ray emission spectra are obtained and compared to available data

  19. Synthesis and electrochemical properties of tin-doped MoS{sub 2} (Sn/MoS{sub 2}) composites for lithium ion battery applications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Lin; Min, Feixia; Luo, Zhaohui; Wang, Shiquan, E-mail: wsqhao@126.com [Hubei University, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules (China); Teng, Fei [Nanjing University of Information Science and Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), School of Environmental Sciences and Engineering (China); Li, Guohua [Zhejiang University of Technology, School of Chemical Engineering and Materials Science (China); Feng, Chuanqi [Hubei University, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules (China)

    2016-12-15

    SnO{sub 2}-MoO{sub 3} composites were synthesized by using (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24}·4H{sub 2}O and SnCl{sub 2}·2H{sub 2}O as raw materials through a simple solvothermal method followed by pyrolysis. Tin-doped MoS{sub 2} (Sn/MoS{sub 2}) flowers have been synthesized by a solvothermal method followed with annealing in Ar(H{sub 2}) atmosphere, with SnO{sub 2}-MoO{sub 3}, thioacetamide (TAA), and urea as starting materials. The doping and the content of Sn-doping play crucial roles in the morphology and electrochemical performance of the MoS{sub 2}. As anode materials for lithium ion battery (LIB), all Sn/MoS{sub 2} composites exhibit both higher reversible capacity and better cycling performance at current density of 200 mA g{sup −1}, compared with MoS{sub 2} without Sn doping. The achieved discharge capacity for Sn/MoS{sub 2} composites is above 1000 mAh g{sup −1} after 100 cycles with nearly 100% coulombic efficiency. The doping of metal Sn in MoS{sub 2} can improve the conductivity of MoS{sub 2} and significantly enhance its electrochemical properties. The good electrochemical performance suggests that the Sn/MoS{sub 2} composite could be a promising candidate as a novel anode material for LIB application. Our present work provides a new approach to the fabrication of anode materials for LIB applications.

  20. Nanostructured metal oxides: promise opportunity and challenge to develop clinically useful 99Mo/99mTc generators using (n, gamma)99Mo

    International Nuclear Information System (INIS)

    Dash, Ashutosh

    2014-01-01

    The role of 99m Tc diagnostic nuclear medicine needs hardly to be reiterated. Today, it is the most widely used radionuclide for single photon emission computed tomography (SPECT) imaging procedures. The current strategy of availing 99m Tc is ensured from column chromatographic 99 Mo/ 99m Tc generators using a bed of acidic alumina. While the column chromatographic 99 Mo/ 99m Tc generator constitute a successful exemplar of availing 99m Tc, the limited capacity of alumina (2-20 mg Mo per g of alumina) for taking up molybdate ions necessitates the use of 99 Mo of the highest specific activity available, as can be found in fission produced 99 Mo (F 99 Mo). In order to reduce dependence of F 99 Mo, the scope of using low specific activity (n,γ) 99 Mo along with high capacity adsorbent is an interesting prospect. In this context, the scope of using nanomaterials as a viable adsorbent seemed attractive by virtue of their huge surface to volume ratios, altered physical properties, tailored surface chemistry, favorable adsorption characteristics, and enhanced surface reactivity resulting from the nanoscale dimensions. This emerging class of adsorbent represents an innovative paradigm and is expected to play an important role in the development of 99 Mo/ 99m Tc generators adaptable to the existing and foreseeable demands. This talk outlines a critical assessment on the role of nanostructured metal oxides, recent developments, the contemporary status, and key challenges and apertures to the near future. (author)