Sample records for bituminous overlays

  1. Bituminization plant Jaslovske Bohunice

    In this leaflet the principle of the bituminization plant for radioactive concentrate (the intermediate liquid radioactive waste generated during the NPP A1, V-1, V-2 operations) solidification used in the Bohunice Radwaste Treatment Centre (BSC RAO) is presented

  2. Cold bituminous mixes

    Delak, Boštjan


    Asphalt mix (short also asphalt) can be obtained from nature (natural asphalt) or produced technically (artificial asphalt), i. e. as a mix of bituminous binder, stone grain, and other additives that improve the asphalt properties. The beginnings of the use of asphalt can be traced from 6,000 to 4,000 BC since people back then knew some materials that contained bitumen as a binder. A more frequent use of the natural asphalt, however, starts around 3,000 BC. Different peoples used it primar...

  3. Overlay accuracy fundamentals

    Kandel, Daniel; Levinski, Vladimir; Sapiens, Noam; Cohen, Guy; Amit, Eran; Klein, Dana; Vakshtein, Irina


    Currently, the performance of overlay metrology is evaluated mainly based on random error contributions such as precision and TIS variability. With the expected shrinkage of the overlay metrology budget to interaction with the metrology technology, as the main source of overlay inaccuracy. The most important type of mark imperfection is mark asymmetry. Overlay mark asymmetry leads to a geometrical ambiguity in the definition of overlay, which can be ~1nm or less. It is shown theoretically and in simulations that the metrology may enhance the effect of overlay mark asymmetry significantly and lead to metrology inaccuracy ~10nm, much larger than the geometrical ambiguity. The analysis is carried out for two different overlay metrology technologies: Imaging overlay and DBO (1st order diffraction based overlay). It is demonstrated that the sensitivity of DBO to overlay mark asymmetry is larger than the sensitivity of imaging overlay. Finally, we show that a recently developed measurement quality metric serves as a valuable tool for improving overlay metrology accuracy. Simulation results demonstrate that the accuracy of imaging overlay can be improved significantly by recipe setup optimized using the quality metric. We conclude that imaging overlay metrology, complemented by appropriate use of measurement quality metric, results in optimal overlay accuracy.

  4. Effect of Cement on Properties of Over-Burnt Brick Bituminous Concrete Mixes

    Sarkar, Dipankar; Pal, Manish


    The present investigation is carried out to propose the use of cement coated over burnt brick aggregate in the preparation of bituminous concrete mix. The effect of cement on various mechanical properties such as Marshall stability, flow, Marshall quotient (stability to flow ratio), indirect tensile strength, stripping, rutting and fatigue life of bituminous concrete overlay has been evaluated. In this study, different cement percentages such as 2, 3, 4 and 5 % by weight of aggregate have been mixed with Over Burnt Brick Aggregate (OBBA). The laboratory results indicate that bituminous concrete prepared by 4 % cement coated OBBA gives the highest Marshall stability. The bituminous concrete mix with 4 % cement shows considerable improvement in various mechanical properties of the mix compared to the plain OBBA concrete mix.

  5. Overlays and group actions

    Dydak, Jerzy


    Overlays were introduced by R. H. Fox [6] as a subclass of covering maps. We offer a different view of overlays: it resembles the definition of paracompact spaces via star refinements of open covers. One introduces covering structures for covering maps and $p:X\\to Y$ is an overlay if it has a covering structure that has a star refinement. We prove two characterizations of overlays: one using existence and uniqueness of lifts of discrete chains, the second as maps inducing simplicial coverings...

  6. RADAR PPI Scope Overlay

    National Oceanic and Atmospheric Administration, Department of Commerce — RADAR PPI Scope Overlays are used to position a RADAR image over a station at the correct resolution. The archive maintains several different RADAR resolution...

  7. New holographic overlays

    Hopwood, Anthony I.


    This paper discusses a new type of holographic overlay, FLASHPRINT, which may be used in both security and packaging applications. Unlike the more common embossed holograms currently used, FLASHPRINT leads to reduced set-up costs and offers a simpler process. This reduces the long lead times characteristic of the existing technology and requires the customer to provide only two-dimensional artwork. The overlay material contains a covert 2-D image. The image may be switched on or off by simply tilting the overlay in a light source. The overlay is replayed in the 'on' position to reveal the encoded security message as a highly saturated gold colored image. This effect is operable for a wide range of lighting conditions and viewing geometries. In the 'off' position the overlay is substantially transparent. These features make the visual effect of the overlay attractive to incorporate into product design. They may be laminated over complex printed artwork such as labels and security passes without masking the printed message. When switched 'on' the image appears both sharp and more than seven times brighter than white paper. The image remains sharp and clear even in less favorable lighting conditions. Although the technique offers a low set-up cost for the customer, through its simplicity, it remains as technically demanding and difficult to counterfeit as any holographic process.

  8. Leachability of bituminized radioactive waste. Literature survey

    Bituminized radioactive waste that will be returned from COGEMA, France is planned to be disposed of in deep geologic repository in Japan. Data on leachability of radionuclides from bituminized waste are required for the performance assessment of the disposal. We made a literature survey on bitumen and bituminized radioactive waste, placing emphasis on leach tests and leach data in terms of geologic disposal. This survey revealed that reliable leach data on transuranium elements and data obtained under reducing conditions that is characteristic to deep underground are lacking. (author). 64 refs

  9. Bituminous reference document: synthesis of knowledge on the long time behavior of bituminous packages

    This document is a synthesis of the knowledge acquired at the CEA on the behavior of bituminous packages. In this framework, the CEA studied bituminous packages in generic conditions of a package lifetime. The main factors, the evolution mechanisms and influential parameters have been determined and quantitative s simulation have been developed. After a description of the main initial bituminous packages characterizations, the evolutions in saturated and un-saturated environment are exposed. (A.L.B.)

  10. Characterization of overlay mark fidelity

    Adel, Mike; Ghinovker, Mark; Poplawski, Jorge M.; Kassel, Elyakim; Izikson, Pavel; Pollentier, Ivan K.; Leray, Philippe; Laidler, David W.


    In this publication we introduce a new metric for process robustness of overlay metrology in microelectronic manufacturing. By straightforward statistical analysis of overlay metrology measurements on an array of adjacent, nominally identical overlay targets the Overlay Mark Fidelity (OMF) can be estimated. We present the results of such measurements and analysis on various marks, which were patterned using a DUV scanner. The same reticle set was used to pattern wafers on different process layers and process conditions. By appropriate statistical analysis, the breakdown of the total OMF into a reticle-induced OMF component and a process induced OMF component was facilitated. We compare the OMF of traditional box-in-box overlay marks with that of new gratingbased overlay marks and show that in all cases the grating marks are superior. The reticle related OMF showed an improvement of 30 % when using the new grating-based overlay mark. Furthermore, in a series of wafers run through an STI-process with different Chemical Mechanical Polish (CMP) times, the random component of the OMF of the new grating-based overlay mark was observed to be 40% lower and 50% less sensitive to process variation compared with Box in Box marks. These two observations are interpreted as improved process robustness of the grating mark over box in box, specifically in terms of reduced site by site variations and reduced wafer to wafer variations as process conditions change over time. Overlay Mark Fidelity, as defined in this publication, is a source of overlay metrology uncertainty, which is statistically independent of the standard error contributors, i.e. precision, TIS variability, and tool to tool matching. Current overlay metrology budgeting practices do not take this into consideration when calculating total measurement uncertainty (TMU). It is proposed that this be reconsidered, given the tightness of overlay and overlay metrology budgets at the 70 nm design rule node and below.

  11. Electrically conductive polymer concrete overlays

    Fontana, J. J.; Webster, R. P.


    The use of cathodic protection to prevent the corrosion of reinforcing steel in concrete structures has been well established. Application of a durable, skid-resistant electrically conductive polymer concrete overlay would advance the use of cathodic protection for the highway industry. Laboratory studies indicate that electrically conductive polymer concrete overlays using conductive fillers, such as calcined coke breeze, in conjunction with polyester or vinyl ester resins have resistivities of 1 to 10 ohm-cm. Both multiple-layer and premixed mortar-type overlays were made. Shear bond strengths of the conductive overlays to concrete substrates vary from 600 to 1300 psi, with the premixed overlays having bond strengths 50 to 100% higher than the multiple-layer overlays.

  12. Overlay networks toward information networking

    Tarkoma, Sasu


    With their ability to solve problems in massive information distribution and processing, while keeping scaling costs low, overlay systems represent a rapidly growing area of R&D with important implications for the evolution of Internet architecture. Inspired by the author's articles on content based routing, Overlay Networks: Toward Information Networking provides a complete introduction to overlay networks. Examining what they are and what kind of structures they require, the text covers the key structures, protocols, and algorithms used in overlay networks. It reviews the current state of th

  13. 30 CFR 716.4 - Special bituminous coal mines.


    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Special bituminous coal mines. 716.4 Section... INTERIOR INITIAL PROGRAM REGULATIONS SPECIAL PERFORMANCE STANDARDS § 716.4 Special bituminous coal mines. (a) Definition. Special bituminous coal surface mines as used in this section means those...

  14. A Cooperative Network Monitoring Overlay

    Castro, Vasco; Carvalho, Paulo; Lima, Solange


    This paper proposes a flexible network monitoring overlay which resorts to cooperative interaction among measurement points to monitor the quality of network services. The proposed overlay model, which relies on the definition of representative measurement points, the avoidance of measurement redundancy and a simple measurement methodology as main design goals, is able to articulate intra- and inter-area measurements efficiently. The distributed nature of measurement control and data confers to ...

  15. Towards Social Profile Based Overlays

    Wolinsky, David Isaac; Boykin, P Oscar; Figueiredo, Renato


    Online social networking has quickly become one of the most common activities of Internet users. As social networks evolve, they encourage users to share more information, requiring the users, in turn, to place more trust into social networks. Peer-to-peer (P2P) overlays provide an environment that can return ownership of information, trust, and control to the users, away from centralized third-party social networks. In this paper, we present a novel concept, social profile overlays, which enable users to share their profile only with trusted peers in a scalable, reliable, and private manner. Each user's profile consists of a unique private, secure overlay, where members of that overlay have a friendship with the overlay owner. Profile data is made available without regard to the online state of the profile owner through the use of the profile overlay's distributed data store. Privacy and security are enforced through the use of a public key infrastructure (PKI), where the role of certificate authority (CA) i...

  16. Evaluation of the Cargill Safelane Surface Overlay

    Sprinkel, Michael M.; Daniel S. Roosevelt; Flintsch, Gerardo W.; de León Izeppi, Edgar; Mokarem, David W.


    A recent development in polymer concrete overlays is the Cargill SafeLane surface overlay (SafeLane overlay). The 3/8-in-thick overlay is constructed with epoxy and broadcast aggregates, as are typical multiple-layer epoxy overlays that are used to provide a skid-resistant wearing surface for bridge decks that protects the decks again intrusion by chloride ions. Reportedly, the SafeLane overlay is unique in that Cargill indicates that the limestone aggregate used in the overlay can absorb and...

  17. Overlay welding irradiated stainless steel

    An overlay technique developed for welding irradiated stainless steel may be important for repair or modification of fusion reactor materials. Helium, present due to n,α reactions, is known to cause cracking using conventional welding methods. Stainless steel impregnated with 3 to 220 appm helium by decay of tritium was used to develop a welding process that could be used for repair. The result was a gas metal arc weld overlay technique with low-heat input and low-penetration into the helium-containing material. Extensive metallurgical and mechanical testing of this technique demonstrated substantial reduction of helium embrittlement damage. The overlay technique was applied to irradiated 304 stainless steel containing 10 appm helium. Surface cracking, present in conventional welds made on the same steel at lower helium concentrations, was eliminated. Underbead cracking, although greater than for tritium charged and aged material, was minimal compared to conventional welding methods

  18. Evaluating Self Healing Capability of Bituminous Mastics

    Qiu, J.; Ven, M. van de; Wu, S.; Yu, J.; Molenaar, A.


    The self-healing capability of bituminous materials has been known for many years. Researches were mostly focused on the self healing behaviour during load repetitions. The tests are either time consuming and/or complex. In this paper, a simple self healing test procedure is presented combining the fracture-healing-re-fracture test (FHR) with morphological observations. A fast displacement speed loading was applied first to produce a flat open crack with a crack width of 100–200 μm. Then the ...

  19. Comparing Maintenance Strategies for Overlays

    Krishnamurthy, Supriya; Aurell, Erik; Haridi, Seif


    In this paper, we present an analytical tool for understanding the performance of structured overlay networks under churn based on the master-equation approach of physics. We motivate and derive an equation for the average number of hops taken by lookups during churn, for the Chord network. We analyse this equation in detail to understand the behaviour with and without churn. We then use this understanding to predict how lookups will scale for varying peer population as well as varying the sizes of the routing tables. We then consider a change in the maintenance algorithm of the overlay, from periodic stabilisation to a reactive one which corrects fingers only when a change is detected. We generalise our earlier analysis to underdstand how the reactive strategy compares with the periodic one.

  20. Overlay networking:applications and research challenges

    LU Jun-xiu; SHAN Xiu-ming; REN Yong


    Overlay networking is one of the perspective solutions to today's Intemet challenges. At basic service level, overlay networks can serve as a supplement and enhancement of existing services, such as routing and addressing. At high application level, overlay networks can be used for applications, which are difficult to deploy in existing IP architecture with some specific reasons, e.g., they need high-level information, which is hard to obtain by underlying layers. To address the heterogeneity of today's Internet, overlay networks provide ways to service availability and desirable performance while retaining scalability. In contrast to changing the existing network layer, overlay networks allow bootstrapping, which is most important in the development of Internet infrastructure. Various applications of overlay networking are clarified in this paper. Research challenges including routing and searching in overlay networking are also identified.

  1. Meeting overlay requirements for future technology nodes with in-die overlay metrology

    Schulz, Bernd; Seltmann, Rolf; Busch, Jens; Hempel, Fritjof; Cotte, Eric; Alles, Benjamin


    As a consequence of the shrinking sizes of the integrated circuit structures, the overlay budget shrinks as well. Overlay is traditionally measured with relatively large test structures which are located in the scribe line of the exposure field, in the four corners. Although the performance of the overlay metrology tools has improved significantly over time it is questionable if this traditional method of overlay control will be sufficient for future technology nodes. For advanced lithography techniques like double exposure or double patterning, in-die overlay is critical and it is important to know how much of the total overlay budget is consumed by in-die components. We reported earlier that small overlay targets were included directly inside die areas and good performance was achieved. This new methodology enables a wide range of investigations. This provides insight into processes which were less important in the past or not accessible for metrology. The present work provides actual data from productive designs, instead of estimates, illustrating the differences between the scribe line and in-die registration and overlay. The influence of the pellicle on pattern placement on mask and wafer overlay is studied. Furthermore the registration overlay error of the reticles is correlated to wafer overlay residuals. The influence of scanner-induced distortions (tool to tool differences) on in-die overlay is shown. Finally, the individual contributors to in-die-overlay are discussed in the context of other overlay contributors. It is proposed to use in-die overlay and registration results to derive guidelines for future overlay and registration specifications. It will be shown that new overlay correction schemes which take advantage of the additional in-die overlay information need to be considered for production.

  2. Crumb Rubber in cold recycled bituminous mixes

    Dondi, Giulio; Tataranni, Piergiorgio; Pettinari, Matteo;


    . Cold recycling is, among the recycling techniques, certainly the most studied and developed: it allows the recovering of bituminous material from an existing pavement without the addition of heat, whilst ensuring the creation of high quality bound base layers. A wide range of materials have been tested...... together with Reclaimed Asphalt Pavement (RAP) and, consequently, there is a large number of variables that can be considered in the mix-design process of new eco-friendly Cold Recycled Mixes. In particular, the present research involves the use of Crumb Rubber within a mixture containing 100% Reclaimed...... Asphalt Pavement, cold recycled with bitumen emulsion and cement. Two different Crumb Rubbers were adopted: one from the ambient production method, and one produced with the cryogenic process. The goal of this research project was to analyze and evaluate the different physical and mechanical...

  3. Skid resistance of bituminous surfaces in Ohio

    Colony, D. C.


    Statistical studies of skid number (SN) on the state highway system in Ohio reveal apparently systematic variations in distributions of SN among the twelve districts in the state. These variations appear to be significantly related to traffic and to geological characteristics of a given district. Regression calculations using traffic index, a function of ADT and age of the pavement surface in months, show a high correlation with SN, although standard errors of estimate were too large to make the equations useful for predicting SN from traffic variables. Similar results were obtained by elating SN to physiographic features in the state. Pavement surface type (bituminous or pcc) and coarse aggregate type (limestone, gravel or slag) are significantly related to SN.

  4. Radon concentration measurements in bituminous coal mines

    Radon measurements were carried out in Kozlu, Karadon and Uezuelmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m-3. It is suggested that the ventilation rates should be rearranged to reduce the radon concentration. (authors)

  5. TES overlayed on MOLA DEM


    This image is TES thermal data (Orbit 222) overlayed on the MOLA DEM. The color scale is TES T18-T25, which is a cold spot index. The grey scale is MOLA elevation in kilometers. Most cold spots can be attributed to surface spectral emissivity effects. Regions that are colored black-violet-blue have near unity emissivity and are coarse grained CO2. Regions that are yellow-red are fined grained CO2. The red-white spot located approximately 300W85N is our most likely candidate for a CO2 snow storm.

  6. Analysis Of Overlay Distortion Patterns

    Armitage, John D.; Kirk, Joseph P.


    A comprehensive geometrical approach is presented for the least-squares analysis of overlay distortion patterns into useful, physically meaningful systematic distortion subpatterns and an essentially non-systematic residue. A scheme of generally useful distortion sub-patterns is presented in graphic and algorithmic form; some of these sub-patterns are additions to those already in widespread use. A graphic and geometric approach is emphasized rather than an algebraic or statistical approach, and an example illustrates the value in utilizing the pattern-detecting ability of the eye-brain system. The conditions are described under which different distortion sub-patterns may interact, possibly leading to misleading or erroneous conclusions about the types and amounts of different distortions present. Examples of typical interaction situations are given, and recommendations are made for analytic procedures to avoid misinterpretation. It is noted that the lower-order distortion patterns preserve straight-line linearity, but that higher-order distortion may result in straight lines becoming curved. The principle of least-squares analysis is outlined and a simple polynomial data-fitting example is used to illustrate the method. Algorithms are presented for least-squares distortion analysis of overlay patterns, and an APL2 program is given to show how this may easily be implemented on a digital computer. The appendix extends the treatment to cases where small-angle approximation is not permissible.

  7. Development of non-standard equipment of bituminization line

    A brief description is presented of some components of the bituminization line developed at the Research Institute of Chemical Installations in Brno. The film rotor evaporator has an evaporation area of 2 m2. The mixing tank is the main technological assembly for processing loose materials, i.e., sorbents and fly ash which it mixes with melted bitumen. The screw conveyor with a three-way valve is designed for batching the dried radioactive sorbent and fly ash into mixing tanks. Attention is also devoted to certain systems of measurement and control of the bituminization line, namely to measurement of the level of the bituminization product, the flow rate of bituminization emulsion and the water-sorbent mixture and to the diagnostics of failure and accident conditions of the film rotor evaporator. (Z.M.)

  8. Bituminous and asphaltic membranes for radioactive waste repositories on land

    The aim of the study has been to identify, within generic designs for waste facilities, areas where bituminous materials might be incorporated as a barrier. The report is presented in three sections: Part I - The properties of bitumen are described, with particular reference to the long-term behaviour of the material. The durability of bitumen is discussed, including aspects such as ageing, microbial degradation, chemical resistance and radiation resistance. Part II -The use of bituminous materials in hydraulic engineering is outlined. Much of this section of the report concentrates on the use of bituminous materials in embankment dams and reservoir construction. A review of material technology and construction techniques is presented and a detailed assessment made of the performance of the materials in service. Part III - Generic trench type radioactive waste repository designs incorporating bituminous materials are presented. Material and construction specifications for the designs are detailed, and a performance assessment presented. (author)

  9. Long-term properties of bituminized waste products

    This study is a survey of the factors of importance for long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are ralated to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product. (author)

  10. Long-term properties of bituminized waste products

    This study is a survey of the factors of importance for the long term behaviour of bituminized ion exchange resins. Phenomena occurring in bituminized waste products affected by the treatment, storage and disposal are identified. Test methods have been developed for characterizing product properties, which are important for the long-term behaviour. The long-term properties of bituminized ion-exchange resins are studied in a repository environment with access of water equilibrated with concrete. In these circumstances the most important properties are related to the interactions of bituminized waste with the surrounding barriers. The most important phenomena are water uptake due to rehydration of the resins and subsequent swelling of the product

  11. Effects of bituminous layer as backfill material on mechanical behavior in tunnel model

    Moriyoshi, Akihiro; Takano, Shin-ei; Urata, Hiroyuki; Suzuki, Tetsuya; Yoshida, Takaki


    This paper describes the effects of bituminous material as a backfill material on mechanical behavior in model tunnel in laboratory. It is known that load spreading and relaxation of bituminous material are good properties. Then if we use bituminous material as a backfill material of tunnel, the tunnel will have waterproof, good load spreading property. We used new bituminous material (Aquaphalt) which can solidify in water. We conducted relaxation test in tension for new bituminous mat...

  12. LMS filters for cellular CDMA overlay

    Wang, J.


    This paper extends and complements previous research we have performed on the performance of nonadaptive narrowband suppression filters when used in cellular CDMA overlay situations. In this paper, an adaptive LMS filter is applied to cellular CDMA overlay situations in order to reject narrowband interference.

  13. The bituminous sands : a Canadian mirage?

    Rousse, D.R. [Quebec Univ., Chicoutimi, PQ (Canada). Dept. des Sciences Appliquees; Nasr, G.J. [Lebanese Univ., Roumieh (Lebanon). Faculty of Engineering; Turcotte, S.F. [Quebec Univ., Montreal, PQ (Canada). Centre d' Etudes Internationales et Mondialisation; Salah, N.B. [Ecole Superieure des Sciences et Techniques De Tunis, Tunis (Tunisia). LMMP


    This paper examined the controversy about the potential role of a significant increase in Canadian oil sands production in order to bridge the upcoming gap between the world's increasing energy demand and the total recoverable oil supply. The paper presented the actual potential of different scenarios and considered the prediction cost forecasts. A brief overview of environmental impacts and the real return on investments were also provided. Environmental impacts that were considered included land degradation; water contamination; ecosystem damage; and air pollution. Nuclear energy was also presented as a possible solution. The paper demonstrated that even in a very optimistic scenario, Canada's oil sands accelerated production has a negligible effect on the aforementioned gap, has a considerable impact on environment that has yet to be accounted for. Energy ratios that were presented included energy return on energy investment; energy available on energy used; and energy payback. It was concluded that enhanced recovery techniques are clearly needed for future sustainable exploitation of these bituminous sands. 32 refs., 1 fig.

  14. Overlay journals, repositories and the evolution of scholarly communication

    Brown, J. A.


    This paper examines the part overlay journals can play in developing new roles for repositories in the scholarly communication process. This requires that we answer some outstanding questions about the overlay journal model: · How are overlay journals distinct from other overlay services and other journals? · What business models are applicable? · What opportunities do overlay journals offer to repositories? And, perhaps most importantly: · What value can an overlay journ...

  15. Bituminization of low- and intermediate-level radioactive concentrates

    The results and experiences are summed up from the research and development of the technology of bituminization of low- and intermediate-level radioactive concentrates generated in the operation of nuclear power plants with WWER-440 reactors. The experiments took place on a pilot plant bituminization line with various model solutions at an evaporator capacity of 70, 100 and 140 litres per hour. The composition of the solutions changed in dependence on the knowledge of the composition of actual concentrates in the V-1 nuclear power plant at Jaslovske Bohunice. The following factors were studied in the concentrate: the effect of its pH, its borate content and content of metal carbonates, the content of organic acid salts, the content of detergents, etc., on the process of bituminization. Physico-chemical conditions are described under which the operation of the evaporator was fail-safe and filling of the bituminization product with salts homogeneous. A low water content of up to 1% was achieved. The properties of the bituminization product were negatively affected by a high level of heavy metal oxides, surfactants, oxalates and citrates. In order to improve the properties of the product it will be necessary to replace bitumen emulsion Silembit-60 used as reinforcement matrix, by a different type of bitumen. (Z.M.)

  16. Routing on Overlay Networks : Developments and Challenges

    Popescu, Adrian


    Overlay networks are networks operating on the inter-domain level, where the edge hosts learn of each other and, based on knowledge of underlying network performance, they form loosely coupled neighboring relationships. These relationships can be used to induce a specific graph, where nodes are representing hosts and edges are representing neighboring relationships. Graph abstraction and the associated graph theory can be further used to formulate routing algorithms on overlay networks. The m...

  17. Synapse: a Scalable Protocol for Interconnecting Heterogeneous Overlay Networks

    Liquori, Luigi; Tedeschi, Cédric; Vanni, Laurent; Ciancaglini, Vincenzo; Bongiovanni, Francesco; Marinkovic, Bojan


    International audience This paper presents Synapse, a scalable protocol for information retrieval over the inter-connection of heterogeneous overlay networks. Applications on top of Synapse see those intra-overlay networks as a unique inter-overlay network. Scalability in Synapse is achieved via co-located nodes, i.e. nodes that are part of multiple overlay networks at the same time. Co-located nodes, playing the role of neural synapses and connected to several overlay networks, give a lar...

  18. Measurement of heat generation from simulated bituminized product

    The fire and explosion incident occurred at Bituminization Demonstration Facility of PNC Tokai Works on March 11, 1997. In order to ascertain the cause of incident, the investigation has been pushed forward. For the investigation, we prepared simulated bituminized product of measurement of heat generation in low temperature region less than 200degC. We used calvet Calorimeter MS80 for the heat generation measurement. Result of measurement, we were able to catch the feeble heat generation from bituminized product. The maximum calorific value that was able to detect it in isothermal measurement was approximately 1 mW/g in 160degC. It was approximately 2 mW/g in 200degC. And, as the another measurement, the measurement condition went heat rate by 0.01degC/minute, the highest temperature 190degC. As a result, the maximum generation of heat value that was able to detect it was approximately 0.5 mW/g. I changed simulated bituminized products and measured these. A difference of condition is salt particle size, salt content rate (45%, 60%), addition of the simulated precipitate. But there was not a difference in the generation of heat characteristic detected. (author)

  19. Unexpectedly high uptake of palladium by bituminous coals

    Lakatos, J. [Research Lab. for Mining Chemistry, Hungarian Academy of Sciences, Miskolc-Egyetemvaros (Hungary); Brown, S.D.; Snape, C.E. [Univ. of Strathclyde, Dept. of Pure and Applied Chemistry, Glasgow (United Kingdom)


    The uptake of palladium as a conversion catalyst onto coals of different rank was investigated. Palladium fixation occurs by a different mode to that for alkaline earth and first row transition metals. Therefore, the dispersion of relatively high concentration of palladium by an ion sorption process is even possible for bituminous coals. (orig.)

  20. Examination of overlay repaired BWR pipe joints

    Intergranular stress corrosion cracking (IGSCC) in a large number of austenitic stainless steel girth welds in boiling water reactor (BWR) piping has prompted the development of the weld overlay for repair (WOR) as a short-term remedy. It is necessary to examine the deposited overlay weld material for adequate definition of its condition and to monitor the overlaid IGSCC to determine if it grows past the bounds assumed in the design of the repair. This paper reports on NDE techniques evaluated using weld overlaid pipe samples containing known defects, overlaid samples removed from BWR service, and overlaid weld joints in plant. These samples included overlays containing fabrication defects and overlaid pipes containing deep and shallow laboratory- and service-induced IGSCC

  1. Patent Overlay Mapping: Visualizing Technological Distance

    Kay, Luciano; Youtie, Jan; Porter, Alan L; Rafols, Ismael


    The purpose of this paper is to present a new global patent map that represents all technological categories, and a method to locate patent data of individual organizations and technological fields on the global map. This second patent overlay map technique is shown to be of potential interest to support competitive intelligence and policy decision-making. The global patent map is based on similarities in citing-to-cited relationships between categories of the International Patent Classification (IPC) of European Patent Office (EPO) patents from 2000 to 2006. This patent dataset, extracted from PatStat database, represents more than 760,000 patent records in more than 400 IPC categories. To illustrate the kind of analytical support offered by this approach, the paper shows the overlay of nanotechnology-related patenting activities of two companies and two different nanotechnology subfields on to the global patent map. The exercise shows the potential of patent overlay maps to visualize technological areas and...

  2. Exploring overlay journals: the RIOJA project

    CERN. Geneva


    Researchers in cosmology and astrophysics depend on the arXiv repository for the registration and dissemination of their work, as well as for current awareness, yet they continue to submit papers to journals for review. Could rapid quality certification be overlaid directly onto the arXiv repository? This presentation introduces the RIOJA (Repository Interface to Overlaid Journal Archives) project, on which a group of cosmology researchers from the UK is working with UCL Library Services and Cornell University. The project is creating a tool to support the overlay of journals onto repositories, and will demonstrate a cosmology journal overlaid on top of arXiv. RIOJA will also work with the cosmology community to explore the social and economic aspects of journal overlay in this discipline: what other value, besides the quality stamp, does journal publication typically add? What are the costs of the ideal overlay journal for this community, and how could those costs be recovered? Would researchers real...

  3. Verification of ultrasonic indications in austenitic overlay

    An austenitic overlay on steel 15Kh2MFA was tested by an ultrasonic probe. Overlays of this kind are used in nuclear reactor pressure vessels. The results of the ultrasonic method were compared with those of the metallographic method. Metallographic analysis showed that the majority of defects found by ultrasonic tests included clusters of cavities, welded-in slag and cracks, which mostly occurred between the weld beads. The experiments gave evidence that defects not smaller than 0.5 mm in size can be well detected at depths not exceeding 7 mm. (M.D.). 3 figs

  4. Hybrid overlay metrology for high order correction by using CDSEM

    Leray, Philippe; Halder, Sandip; Lorusso, Gian; Baudemprez, Bart; Inoue, Osamu; Okagawa, Yutaka


    Overlay control has become one of the most critical issues for semiconductor manufacturing. Advanced lithographic scanners use high-order corrections or correction per exposure to reduce the residual overlay. It is not enough in traditional feedback of overlay measurement by using ADI wafer because overlay error depends on other process (etching process and film stress, etc.). It needs high accuracy overlay measurement by using AEI wafer. WIS (Wafer Induced Shift) is the main issue for optical overlay, IBO (Image Based Overlay) and DBO (Diffraction Based Overlay). We design dedicated SEM overlay targets for dual damascene process of N10 by i-ArF multi-patterning. The pattern is same as device-pattern locally. Optical overlay tools select segmented pattern to reduce the WIS. However segmentation has limit, especially the via-pattern, for keeping the sensitivity and accuracy. We evaluate difference between the viapattern and relaxed pitch gratings which are similar to optical overlay target at AEI. CDSEM can estimate asymmetry property of target from image of pattern edge. CDSEM can estimate asymmetry property of target from image of pattern edge. We will compare full map of SEM overlay to full map of optical overlay for high order correction ( correctables and residual fingerprints).

  5. Colors, colored overlays, and reading skills

    Arcangelo eUccula


    Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

  6. Performance of PAHs emission from bituminous coal combustion

    严建华; 尤孝方; 李晓东; 倪明江; 尹雪峰; 岑可法


    Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion.

  7. Amenability of Muzret bituminous coal to oil agglomeration

    Sahinoglu, E.; Uslu, T. [Karadeniz Technical University, Department of Mining Engineering, 61080 Trabzon (Turkey)


    Laboratory scale agglomeration tests were undertaken to investigate the amenability of Muzret (Yusufeli-Artvin) bituminous coal to oil agglomeration. Kerosene was extensively used as oil in the tests. In addition, fuel oil, diesel oil, and hazelnut oil were also used in order to determine the effect of oil type. The effects of the parameters including coal content, kerosene content, agglomeration time, coal particle size, pH, oil type, and agitation rate, on the combustible matter recovery, ash reduction and pyritic sulphur reduction, were investigated. It was found that Muzret bituminous coal could be readily cleaned by oil agglomeration with substantial reductions in ash and pyritic sulphur content. Maximum combustible matter recovery, ash reduction and pyritic sulphur reduction were achieved to be 85.54%, 59.98%, and 85.17%, respectively. (author)

  8. Identification of aggregates for Tennessee bituminous surface courses

    Sauter, Heather Jean

    Tennessee road construction is a major venue for federal and state spending. Tax dollars each year go to the maintenance and construction of roads. One aspect of highway construction that affects the public is the safety of its state roads. There are many factors that affect the safety of a given road. One factor that was focused on in this research was the polish resistance capabilities of aggregates. Several pre-evaluation methods have been used in the laboratory to predict what will happen in a field situation. A new pre-evaluation method was invented that utilized AASHTO T 304 procedure upscaled to accommodate surface bituminous aggregates. This new method, called the Tennessee Terminal Textural Condition Method (T3CM), was approved by Tennessee Department of Transportation to be used as a pre-evaluation method on bituminous surface courses. It was proven to be operator insensitive, repeatable, and an accurate indication of particle shape and texture. Further research was needed to correlate pre-evaluation methods to the current field method, ASTM E 274-85 Locked Wheel Skid Trailer. In this research, twenty-five in-place bituminous projects and eight source evaluations were investigated. The information gathered would further validate the T3CM and find the pre-evaluation method that best predicted the field method. In addition, new sources of aggregates for bituminous surface courses were revealed. The results of this research have shown T3CM to be highly repeatable with an overall coefficient of variation of 0.26% for an eight sample repeatability test. It was the best correlated pre-evaluation method with the locked wheel skid trailer method giving an R2 value of 0.3946 and a Pearson coefficient of 0.710. Being able to predict field performance of aggregates prior to construction is a powerful tool capable of saving time, money, labor, and possibly lives.

  9. Patent Overlay Mapping: Visualizing Technological Distance

    Kay, Luciano; Newman, Nils; Youtie, Jan; Porter, Alan L.; Rafols, Ismael


    This paper presents a new global patent map that represents all technological categories and a method to locate patent data of individual organizations and technological fields on the global map. This overlay map technique may support competitive intelligence and policy decision making. The global patent map is based on similarities in citing-to-cited relationships between categories of the International Patent Classification (IPC) of European Patent Office (EPO) patents from 2000 to 2006. Th...

  10. Süperpozisyon apareyleri (*) (Overlay Dentures)

    MUĞAN, Nuri; Cansevergil, Esengün


    SUMMARYRemovable partial or complete prothèses which are used to alleviate maxillary constriction and discrepancies in vertical -dimension are called « overlay dentures». The patients maxillary teeth or ridge is overiayed by acriylic and the artificial teeth are positioned in accordance with the mandibular teeth to establish a better occlusion as well as to improve the estetios of the individual. The improved anterior tooth relationships also provide the anatomic basis for the correct produc...

  11. Adaptive Lattice Filters for CDMA Overlay

    Prahatheesan, V; Wang, J.


    This paper presents the behavior of reflection coefficients of a stochastic gradient lattice (SGL) filter applied to a code-division multiple-access overlay system. Analytic expressions for coefficients for a two-stage filter are derived in a Rayleigh fading channel with the presence of narrow-band interference and additive white Gaussian noise. It is shown that the coefficients of the lattice filter exhibit separate tracking and convergent properties,and that compared to an LMS filter, the l...

  12. Overlay Alignment Using Two Photonic Crystals

    Peng, C; Morton, K; Yu, Z; Chou, Stephen Y.; Morton, Keith; Peng, Can; Yu, Zhaoning


    In this paper we proposed a novel overlay alignment method using two sets of identical photonic crystals (PhCs). In this method the reflection or transmission spectrum of the two overlaid photonic crystals is measured to help wafer tilt, yaw rotation, and translation aligning. The initial testing results with two 1D photonic crystals and analysis of the alignment accuracy are presented. This method is particularly useful in building photonic crystal stacks with nanoimprint lithography (NIL).

  13. Overlay Tolerances For VLSI Using Wafer Steppers

    Levinson, Harry J.; Rice, Rory


    In order for VLSI circuits to function properly, the masking layers used in the fabrication of those devices must overlay each other to within the manufacturing tolerance incorporated in the circuit design. The capabilities of the alignment tools used in the masking process determine the overlay tolerances to which circuits can be designed. It is therefore of considerable importance that these capabilities be well characterized. Underestimation of the overlay accuracy results in unnecessarily large devices, resulting in poor utilization of wafer area and possible degradation of device performance. Overestimation will result in significant yield loss because of the failure to conform to the tolerances of the design rules. The proper methodology for determining the overlay capabilities of wafer steppers, the most commonly used alignment tool for the production of VLSI circuits, is the subject of this paper. Because cost-effective manufacturing process technology has been the driving force of VLSI, the impact on productivity is a primary consideration in all discussions. Manufacturers of alignment tools advertise the capabilities of their equipment. It is notable that no manufacturer currently characterizes his aligners in a manner consistent with the requirements of producing very large integrated circuits, as will be discussed. This has resulted in the situation in which the evaluation and comparison of the capabilities of alignment tools require the attention of a lithography specialist. Unfortunately, lithographic capabilities must be known by many other people, particularly the circuit designers and the managers responsible for the financial consequences of the high prices of modern alignment tools. All too frequently, the designer or manager is confronted with contradictory data, one set coming from his lithography specialist, and the other coming from a sales representative of an equipment manufacturer. Since the latter generally attempts to make his

  14. Rewiring Peer Connections over Semantic Overlay Networks

    Ραφτοπούλου, Παρασκευή


    Today's content providers are naturally distributed and produce large amounts of information every day, making peer-to-peer data management a promising approach offering scalability, adaptivity to dynamics and failure resilience. The management of large volumes of data in peer-to-peer networks has generated additional interest in methods for effective network organisation based on providers' contents and consequently, in methods supporting information retrieval. Overlay architectu...

  15. Facilitating Service Discovery with Semantic Overlay

    Hai Jin; Hao Wu; Xiao-Min Ning


    Service Oriented Architecture (SOA) and Peer-to-Peer (P2P) computing share many common characteristics.It is believed that the combination of the two emerging techniques is a very promising method in promoting the web services (WS). Because the service discovery plays a key role in the integration, here a P2P-based framework to manage the knowledge of service and locating services is proposed. In this paper, the details of the principle, constructing and maintaining of service semantic overlay architecture have been described, and the way how the semantic overlay facilitates discovery of service resources is illustrated. To enable the semantic web service superiority, Service Ontology, which is considered as the service semantic model, is employed to depict service. The service discovery includes two phases: searching on the service semantic overlay; and local discovery in peer's service repository. Various solutions have been proposed to realize those two phases.Furthermore, tests are carried out to evaluate service discovery on the architecture.

  16. Wetting of bituminized ion-exchangers under simulated repository conditions

    According to the present plans the spent nuclear fuel from four Finnish nuclear power units will be transferred after interim storage to the final disposal site where it will be encapsulated and disposed of in a final repository constructed into the bedrock at a depth of 500 meters. Low and medium level waste generated at nuclear power plants will be finally disposed of in caverns constructed in the bedrock at the power plant site. The safety of the final disposal is based on a multibarrier concept and the degree of safety is estimated by using predictive models. The properties of the waste form are taken into account in the design of the repository construction. Bitumen has been chosen as an immobilisation agent for the wet wastes at Olkiluoto Power Plant, where two BWR units, TVO 1 and TVO 2, have separate bituminization facilities designed by Asea-Atom. Properties of bituminized spent ion-exchange resins from Olkiluoto power plant have been studied by VTT Chemical Technology since the late 70's. These studies have concentrated mainly on determining the long-term behaviour of the bituminization product under the repository conditions. Current interest lies on wetted product as a diffusion barrier. For this purpose a microscopic method for the visualisation of the structure of the wetted product has been developed. The equilibration of the samples in simulated concrete groundwater is currently going on at a temperature of 5-8 deg. C. Preliminary results are presented in this paper. Diffusion experiments have been planned for the further characterising of the wetted product as a release barrier for radionuclides including modelling. (author)

  17. Sorption of aqueous phosphorus onto bituminous and lignitous coal ashes

    Aiming at the development of a phosphorus removal technology for waste water, phosphate (PO43-) retention behavior of bituminous and lignitous coal ashes was investigated using a batch reactor. Ash samples, including fresh and weathered fly and bottom ashes, were studied for their sorption isotherms and reversibility. Fly ashes had a much higher phosphate retention capacity (4000-30,000 mg P/kg) than bottom ashes (15-600 mg P/kg). Lignitous coal ashes were more capable of retaining phosphate than bituminous coal ashes. The retention process was largely irreversible, and the irreversibility increased with the increase in the retention capacity. Weathering enlarged the retention capacity of the bituminous bottom ash, but substantially lowered that of the fly ash, likely due to the difference in the weather-induced changes between the fly and bottom ashes. Sorption isotherms of fly ashes were found to be adequately represented by the Langmuir model while those of bottom ashes fitted better to the Freundlich model. Concentrations of Ca2+ and PO43- in the aqueous phase were measured at the end of sorption and desorption experiments, and were compared with solubilities of three calcium phosphate minerals. The aqueous solutions were saturated or super-saturated with respect to tricalcium phosphate (Ca3(PO4)2) and hydroxyapatite (Ca5(PO4)3OH), and slightly under-saturated with respect to amorphous calcium phosphate. It is concluded that precipitation of calcium phosphate is the predominant mechanism for phosphate retention by coal ash under the conditions studied. There is a strong and positive correlation between alkalinity and phosphate sorption capacity. Consequently, acid neutralization capacity (ANC) can be used as an indicator of phosphate sorption capacity of coal ashes

  18. Sorption of aqueous phosphorus onto bituminous and lignitous coal ashes

    Yan Jinying; Kirk, Donald W. [Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5 (Canada); Jia, Charles Q. [Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5 (Canada)], E-mail:; Liu Xinan [College of Chemical Engineering, Chongqing University, Chongqing (China)


    Aiming at the development of a phosphorus removal technology for waste water, phosphate (PO{sub 4}{sup 3-}) retention behavior of bituminous and lignitous coal ashes was investigated using a batch reactor. Ash samples, including fresh and weathered fly and bottom ashes, were studied for their sorption isotherms and reversibility. Fly ashes had a much higher phosphate retention capacity (4000-30,000 mg P/kg) than bottom ashes (15-600 mg P/kg). Lignitous coal ashes were more capable of retaining phosphate than bituminous coal ashes. The retention process was largely irreversible, and the irreversibility increased with the increase in the retention capacity. Weathering enlarged the retention capacity of the bituminous bottom ash, but substantially lowered that of the fly ash, likely due to the difference in the weather-induced changes between the fly and bottom ashes. Sorption isotherms of fly ashes were found to be adequately represented by the Langmuir model while those of bottom ashes fitted better to the Freundlich model. Concentrations of Ca{sup 2+} and PO{sub 4}{sup 3-} in the aqueous phase were measured at the end of sorption and desorption experiments, and were compared with solubilities of three calcium phosphate minerals. The aqueous solutions were saturated or super-saturated with respect to tricalcium phosphate (Ca{sub 3}(PO{sub 4}){sub 2}) and hydroxyapatite (Ca{sub 5}(PO{sub 4}){sub 3}OH), and slightly under-saturated with respect to amorphous calcium phosphate. It is concluded that precipitation of calcium phosphate is the predominant mechanism for phosphate retention by coal ash under the conditions studied. There is a strong and positive correlation between alkalinity and phosphate sorption capacity. Consequently, acid neutralization capacity (ANC) can be used as an indicator of phosphate sorption capacity of coal ashes.

  19. Low-level radioactive wastes bituminization - ion exchange resins

    The present work describes the research and development of low level radioactive waste treatment by bituminization process in Nuclear Technology Development Centre (CDTN). Low level radioactive solid waste was simulated by mixed ion exchange resin. Cation exchange and anion resin were loaded with lithium and boric acid respectively and were incorporated in bitumen of suitable rheological properties. The simulated solid wastes incorporated in bitumen were 30 to 46 weight %. The rheological properties of waste product bitumen-mixed resin have been reported. The waste product with bitumen V-65 showed best physical and rheological properties and grave lowest leaching rates of boron and lithium. (author)

  20. Retardation of the spontaneous ignition of bituminous coal

    Dong, X.; Drysdale, D. [University of Edinburgh, Edinburgh (United Kingdom). Department of Civil Engineering and Building Science


    The effect of five retardants on a bituminous coal has been investigated in a temperature-controlled oven. The activation energy of oxidation in the coal inhibited by one of the retardants increases by up to 20kJ/mol, in comparison to that of the coal wetted with water. The factors affecting inhibition are considered. A kinetic interpretation of the retardation mechanism is proposed, and the possibility of using the most effective retarder in practice is discussed. 12 refs., 1 fig., 2 tabs.

  1. New low-viscosity overlay medium for viral plaque assays

    Garten Wolfgang


    Full Text Available Abstract Background Plaque assays in cell culture monolayers under solid or semisolid overlay media are commonly used for quantification of viruses and antiviral substances. To overcome the pitfalls of known overlays, we tested suspensions of microcrystalline cellulose Avicel RC/CL™ as overlay media in the plaque and plaque-inhibition assay of influenza viruses. Results Significantly larger plaques were formed under Avicel-containing media, as compared to agar and methylcellulose (MC overlay media. The plaque size increased with decreasing Avicel concentration, but even very diluted Avicel overlays (0.3% ensured formation of localized plaques. Due to their low viscosity, Avicel overlays were easier to use than methylcellulose overlays, especially in the 96-well culture plates. Furthermore, Avicel overlay could be applied without prior removal of the virus inoculum thus facilitating the assay and reducing chances of cross-contamination. Using neuraminidase inhibitor oseltamivir carboxylate, we demonstrated applicability of the Avicel-based plaque reduction assay for testing of antiviral substances. Conclusion Plaque assay under Avicel-containing overlay media is easier, faster and more sensitive than assays under agar- and methylcellulose overlays. The assay can be readily performed in a 96-well plate format and seems particularly suitable for high-throughput virus titrations, serological studies and experiments on viral drug sensitivity. It may also facilitate work with highly pathogenic agents performed under hampered conditions of bio-safety labs.

  2. Overlay improvement by ASML HOWA 5th alignment strategy

    Wang, Raf; Chiang, CY; Hsu, Wilson; Yang, Richer; Shih, Todd; Chen, Jackie; Chiu, Jonathan; Lin, Wythe


    Overlay control is more challenging when DRAM volume production continues to shrink its critical dimention (CD) to 70nm and beyond. Effected by process, the overlay behavior at wafer edge is quite different from wafer center. The big contribution to worse overlay at wafer edge which causes yield loss is misalignment. The analysis in wafer edge suggests that high order uncorrectable overlay residuals are often observed by certain process impact. Therefore, the basic linear model used for alignment correction is not sufficient and it is necessary to introduce an advanced alignment correction model for wafer edge overlay improvement. In this study, we demonstrated the achievement of moderating the poor overlay at wafer edge area by using a high order wafer alignment strategy. The mechanism is to use non-linear correction methods of high order models ( up to 5th order), with support by the function High Order Wafer Alignment (known as HOWA) in scanner. Instead of linear model for the 6 overlay parameters which come from average result, HOWA alignment strategy can do high order fitting through the wafer to get more accurate overlay parameters which represent the local wafer grid distortion better. As a result, the overlay improvement for wafer edge is achieved. Since alignment is a wafer dependent correction, with HOWA the wafer to wafer overlay variation can be improved dynamically as well. In addition, the effects of different mark quantity and sampling distribution from HOWA are also introduced in this paper. The results of this study indicate that HOWA can reduce uncorrectable overlay residual by 30~40% and improve wafer-to-wafer overlay variation significantly. We conclude that HOWA is a noteworthy strategy for overlay improvement. Moreover, optimized alignment mark numbers and distribution layout are also key factors to make HOWA successful.

  3. Life extension of boilers using weld overlay protection

    Lai, G.; Hulsizer, P. [Welding Services Inc., Norcross, GA (United States); Brooks, R. [Welding Services Inc., Welding Services Europe, Spijkenisse (Netherlands)


    The presentation describes the status of modern weld overlay technology for refurbishment, upgrading and life extension of boilers. The approaches to life extension of boilers include field overlay application, shop-fabricated panels for replacement of the worn, corroded waterwall and shop-fabricated overlay tubing for replacement of individual tubes in superheaters, generating banks and other areas. The characteristics of weld overlay products are briefly described. Also discussed are successful applications of various corrosion-resistant overlays for life extension of boiler tubes in waste-to-energy boilers, coal-fired boilers and chemical recovery boilers. Types of corrosion and selection of weld overlay alloys in these systems are also discussed. (orig.) 14 refs.

  4. Measurement of residual stresses in weld overlay pipe component

    Weld overlay is one of the improvement methods for austenitic stainless steel suffered intergranular stress corrosion cracking (IGSCC). The weld overlay itself increases the wall thickness and change the stress field from inner to outer surface of pipes. To insure the improvement of the stress field on the pipe after weld overlay, the stress distribution of 10 inches pipes weld overlay mock up specimens were insured in this study. The strain-gage hole-drilling method and FEM analysis were applied to measure and calculate the residual stress along the pipe wall thickness. The results show that it behaves good agreement on the residual stress from the measurement and calculation. The weld overlay also induces a compressive stress field on the inner wall, whereas the tensile stress field is created on the outer wall surface. The mechanical grinding on the weld overlay surface will affect the residual stress distribution about 0.04 inches in depth. (author)

  5. CO Chemisorption at Metal Surfaces and Overlayers

    Hammer, Bjørk; Morikawa, Y.; Nørskov, Jens Kehlet


    A database of ab initio calculations of the chemisorption energy of CO over Ni(111), Cu(111), Ru(0001), Pd(111), Ag(111), Pt(111), Au(111), Cu3Pt(111), and some metallic overlayer structures is presented. The trends can be reproduced with a simple model describing the interaction between the metal...... d states and the CO 2 pi* and 5 sigma states, renormalized by the metal sp continuum. Our model rationalizes the results by Rodriguez and Goodman [Science 257, 897 (1992)] showing a strong correlation between the CO chemisorption energy and the surface core level shift....

  6. CO Chemisorption at Metal Surfaces and Overlayers

    Hammer, Bjørk; Morikawa, Y.; Nørskov, Jens Kehlet


    A database of ab initio calculations of the chemisorption energy of CO over Ni(111), Cu(111), Ru(0001), Pd(111), Ag(111), Pt(111), Au(111), Cu3Pt(111), and some metallic overlayer structures is presented. The trends can be reproduced with a simple model describing the interaction between the metal d states and the CO 2 pi* and 5 sigma states, renormalized by the metal sp continuum. Our model rationalizes the results by Rodriguez and Goodman [Science 257, 897 (1992)] showing a strong correlati...

  7. The reflective cracking in the pavement overlay design

    Pais, Jorge C.; Pereira, Paulo A. A.; Capitão, Silvino Dias; Sousa, J.


    This paper describes a new pavement overlay design method that takes into account the reflective cracking as the most predominant type of overlay distress. This phenomenon is characterized as the propagation of old cracks to the new pavement layer. The models proposed are based on a finite element model that closely approximates actual field phenomena based on measurements done on Arizona and Portugal. Test sections have been constructed to access the effect of overlay thickness, crack width ...

  8. The temperature effect on the reflective cracking of asphalt overlays

    Minhoto, Manuel; Pais, Jorge; Pereira, Paulo


    This paper presents a study about the influence of temperature on the reflective cracking in a flexible road pavement through the evaluation of the asphalt overlay damage associated to traffic and temperature variations throughout a year. This study was developed from a numerical simulation of the asphalt overlay behaviour based on a three-dimensional finite-element analysis, considering the simultaneous loading of traffic and temperature variations. A mechanistic-based overlay design method ...

  9. Molecular Dynamics study of Pb overlayer on Cu(100)

    Karimi, M.; Tibbits, P.; Ila, D.; Dalins, I.; Vidali, G.


    Isothermal-isobaric Molecular Dynamics (MD) simulation of a submonolayer Pb film in c(2x2) ordered structure adsorbed on a Cu(100) substrate showed retention of order to high T. The Embedded Atom Method (EAM) calculated the energy of atoms of overlayer and substrate. The time-averaged squared modulus of the two dimensional structure factor for the Pb overlayer measured the order of the overlayer. The results are for increasing T only, and require verification by simulated cooling.

  10. Shrinkage of Latex-Modified and Microsilica Concrete Overlay Mixtures

    Buchanan, Patricia Michelle


    Highway bridge decks are often overlaid to extend service life by reducing the rate of chloride ion ingress and the rate of corrosion of reinforcing steel in the sound chloride-contaminated concrete that is left in-place. Bridge deck overlays in Virginia are usually either latex-modified concrete or microsilica concrete, and both types of overlay are considered equivalent in terms of performance. However, the latex-modified concrete overlays are more expensive to construct than the microsil...

  11. Weld overlay repairs from conception to long-term qualification

    Weld overlay repairs serve several design functions. These include: structurally reinforcing the flawed location to restore code margins to failure, providing an IGSCC-resistant barrier to crack growth, and imposing a favorable residual stress distribution in the inner portion of the flawed component to inhibit further flaw initiation and growth. The qualification programs confirm that these design functions are maintained with long-term service. A regulatory barrier to long-term operation with weld overlays was the need periodically to inspect overlays and thereby demonstrate continued integrity. Although IGSCC flaws have generally been detected by ultrasonic methods, the repair of these flaws by weld overlay made continued monitoring of the repaired flaw by conventional ultrasonic techniques difficult. Recent developments in ultrasonic examination equipment and techniques, including surface preparation criteria, have enhanced the inspectability of weld overlay repairs and the underlying base material. The original acceptance of weld overlay repairs by the USNRC was for limited service (one or two fuel cycles of operation). However, more recent regulatory guidance, including the recently issued NUREG-0313, Revision 2, recognizes the above technical advances, and provides criteria for acceptance of weld overlays as long-term repairs. Several US utilities have been successful to date in obtaining USNRC approval for extended operation with weld overlays. Some overlays at these plants are currently entering their fourth successful fuel cycle of operation. (author)

  12. Investigation of Iron Aluminide Weld Overlays

    Banovic, S.W.; DuPont, J.B.; Levin, B.F.; Marder, A.R.


    Conventional fossil fired boilers have been retrofitted with low NO(sub)x burners in order for the power plants to comply with new clean air regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion typically has been enhanced resulting in premature tube failure. To protect the existing panels from accelerated attack, weld overlay coatings are typically being applied. By depositing an alloy that offers better corrosion resistance than the underlying tube material, the wastage rates can be reduced. While Ni-based and stainless steel compositions are presently providing protection, they are expensive and susceptible to failure via corrosion-fatigue due to microsegregation upon solidification. Another material system presently under consideration for use as a coating in the oxidation/sulfidation environments is iron-aluminum. These alloys are relatively inexpensive, exhibit little microsegregation, and show excellent corrosion resistance. However, their use is limited due to weldability issues and their lack of corrosion characterization in simulated low NO(sub)x gas compositions. Therefore a program was initiated in 1996 to evaluate the use of iron-aluminum weld overlay coatings for erosion/corrosion protection of boiler tubes in fossil fired boilers with low NO(sub)x burners. Investigated properties included weldability, corrosion behavior, erosion resistance, and erosion-corrosion performance.

  13. Behaviour of bituminized ion-exchangers under repository conditions

    This is a final report containing all the research activities and results from the period 13 July 1997-28 February 2001. The purpose of the research was to study the ageing behaviour of bituminized ion-exchanger product under simulated repository conditions. The chosen temperature in this study was 5-8 deg. C and the equilibration solution used was artificial concrete water to simulate the conditions in the final disposal. The aim was to study the properties of wetted product as a release barrier for such important waste nuclides as Sr-90 and Cs-137, which are normal constituents of the bituminized ion-exchangers. All the nine exchanged waters were analysed by ion chromatography (IC) including the follow-up of the water absorption of the samples. All the samples, which were picked up for microscopic examination, have also been analysed. A saturation-elution test was performed with one diffusion sample using tritium (H-3) as a tracer. The results have been presented and further modelling will be performed later. Further two diffusion samples were tested using H-3, Na-22 and Cl-36 as radioactive tracers. The equilibration solution was artificial concrete ground water spiked with H-3 and Na-22 and in the other case with H-3 and Cl-36. Tritium was an internal reference when comparing the results of the equilibration behaviour of Na-22 and Cl-36. From the radioactive input cells samples were taken as a function of time to monitor the equilibration process. Elution of the samples and modelling of the results will be performed later. Na-22 and Cl-36 were chosen to demonstrate the behaviour of a simple anion and cation. Diffusion tests with important waste nuclides Sr-90 and Cs-137 have been scheduled to years 2001-2002. The aim of the performed research project was to study the barrier properties of the bituminized product. The measured parameters and modelling of the results will reflect the behaviour of the wetted product as a part of the multibarrier system providing

  14. Environmental problems caused by bituminous schist and possible solutions

    Schist, as a disposal of mine, has harmful effects on environment. however, several manners can be utilized to prevent the environmental destruction as well as an economical benefit is gained. In this study, environmental problems caused by bituminous schist and other disposals have been investigated on a specific lignite coal mine where schist is disposed as waste material. Pollution and damage on land and in water sources around the coal district and the villages have been observed, recorded and several solutions to environmental problems have been proposed. Discussed proposals will not only solve the environmental pollution problem but also provide waste management facility. Industrial structure of the district enables such a disposal to be used as an economical raw material. Besides, general effects of the coal mine and the power plant nearby have been discussed from environmental point of view, too. 7 refs

  15. Study of thermal reactivity during bituminization of radioactive waste

    This work deals with the study of chemical reactions and phases transitions which can occur between magnesium nitrate, sodium nitrate, cobalt sulphur product, and nickel potassium ferrocyanide, when they are heated together during bituminization process of nuclear waste. The applied methodology associates a few techniques: temperature, enthalpy, and kinetics of reaction are determined by calorimetry, reaction products are characterised by chemical analyses, mass spectrometry and XRD analysis. Three fields of temperature and energy are observed in function of composition (one compound or a mixture of compounds). The study of reactions between NaNO3 and cobalt sulphur product shows that the presence of water has got an effect on reaction temperature. The study of Mg(NO3)2, 6 H2O and CoS shows an overlapping of different signals, and that the reaction rate is very slow (a few hours). (author)

  16. Finite elements simulation of reflective cracking in asphaltic overlays

    Scarpas, A.; De Bondt, A.H.


    Overlaying is one of the most popular and cost effective techniques of rehabilitation of cracked pavements. The placing of reinforcement between the overlay and the top layer of the cracked pavement is currently being utilised as a possible technique for delaying the development of cracks into the o

  17. Effect of Colored Overlays on Computer Vision Syndrome (CVS

    Mark Rosenfield, MCOptom, PhD


    Full Text Available Background: Colored overlays may produce an improvement in reading when superimposed over printed materials. This study determined whether improvements in reading occur when the overlays are placed over a computer monitor. Methods: Subjects (N=30 read from a computer screen for 10 minutes with either a Cerium or control overlay positioned on the monitor. In a third condition, no overlay was present. Immediately following each trial, subjects reported ocular and visual symptoms experienced during the task. Results: Mean symptom scores following the Cerium, control, and no overlay conditions were 12.83, 17.37, and 15.65, respectively (p=0.47. However, a subgroup of 7 subjects (23% reported significant improvements with the Cerium overlay. The mean symptom scores for the Cerium, control, and no overlay trials for this subgroup were 12.14, 29.86, and 28.93, respectively (p=0.03. No significant improvements in either reading speed or reading errors were observed in this subgroup. Conclusion: The use of colored overlays may provide a treatment method for some subjects reporting symptoms during computer use.

  18. EOS: Evolutionary Overlay Service in Peer-to-Peer Systems

    L. I. Zhijun


    Full Text Available The peer-to-peer (P2P systems nowadays can be mainly classified into two categories: structured and structure-less systems based on their overlay organization. The structured systems can achieve determinate efficiency due to their rigorous structure with the cost of losing robustness and vice versa. We provide a semi-structured overlay based on the separation of routing structures and overlay organizations in this paper and the new overlay can achieve determinate efficiency with high robustness. Moreover, the performance of the existing overlay is determined by the initial design and the overlay can not evolve with the information collected. But the new overlay devised in this paper is evolutionary inherent and accompanied by evolving service (EOS, EOS can improve the performance with the running of the P2P systems. Finally, our evolutionary overlay structure is constructed on the basis of linear algebra. So, the EOS can be theoretically analyzed and the results indicate that EOS can work with preferable integrated performance. The experimental results gained on the simulative platform verify the performance of EOS further.

  19. Weld overlay cladding with iron aluminides

    Goodwin, G.M. [Oak Ridge National Lab., TN (United States)


    The hot and cold cracking tendencies of some early iron aluminide alloy compositions have limited their use in applications where good weldability is required. Using hot crack testing techniques invented at ORNL, and experimental determinations of preheat and postweld heat treatment needed to avoid cold cracking, we have developed iron aluminide filler metal compositions which can be successfully used to weld overlay clad various substrate materials, including 9Cr-1Mo steel, 2-1/4Cr-1Mo steel, and 300-series austenitic stainless steels. Dilution must be carefully controlled to avoid crack-sensitive deposit compositions. The technique used to produce the current filler metal compositions is aspiration-casting, i.e. drawing the liquid from the melt into glass rods. Future development efforts will involve fabrication of composite wires of similar compositions to permit mechanized gas tungsten arc (GTA) and/or gas metal arc (GMA) welding.

  20. Capacity of Intelligent Underlay and Overlay Network

    Ling, Yim; Elling, Jan; Nielsen, Thomas Toftegaard


    This paper suggests a method of dimensioning the cell configuration of radio sites in a cellular network using the intelligent overlay and underlay (IOU) technique. The traffic capacity has been analysed by means of a teletraffic model, which is developed based on the classical theory of overflow...... traffic. The formulas of the model have been implemented with the use of MatLab. To verify the model, measurement methods have been developed to collect the teletraffic information in a real-live GSM network. The measured data indicates that the teletraffic model describes the capacity with high accuracy...... and therefore can be used to dimension the network. The model shows that the increase of capacity for a GSM network with 34 frequencies is about 30%. Further capacity enhancement can be achieved by intelligent frequency planning method which is currently being developed...

  1. Decentralized Overlay for Federation of Enterprise Clouds

    Ranjan, Rajiv


    This chapter describes Aneka-Federation, a decentralized and distributed system that combines enterprise Clouds, overlay networking, and structured peer-to-peer techniques to create scalable wide-area networking of compute nodes for high-throughput computing. The Aneka-Federation integrates numerous small scale Aneka Enterprise Cloud services and nodes that are distributed over multiple control and enterprise domains as parts of a single coordinated resource leasing abstraction. The system is designed with the aim of making distributed enterprise Cloud resource integration and application programming flexible, efficient, and scalable. The system is engineered such that it: enables seamless integration of existing Aneka Enterprise Clouds as part of single wide-area resource leasing federation; self-organizes the system components based on a structured peer-to-peer routing methodology; and presents end-users with a distributed application composition environment that can support variety of programming and execu...

  2. Envelopment technique and topographic overlays in bite mark analysis

    Djeapragassam, Parimala; Daniel, Mariappan Jonathan; Srinivasan, Subramanian Vasudevan; Ramadoss, Koliyan; Jimsha, Vannathan Kumaran


    Aims and Objectives: The aims and objectives of our study were to compare four sequential overlays generated using the envelopment technique and to evaluate inter- and intraoperator reliability of the overlays obtained by the envelopment technique. Materials and Methods: Dental stone models were prepared from impressions made from healthy individuals; photographs were taken and computer-assisted overlays were generated. The models were then enveloped in a different-color dental stone. After this, four sequential cuts were made at a thickness of 1mm each. Each sectional cut was photographed and overlays were generated. Thus, 125 overlays were generated and compared. Results: The scoring was done based on matching accuracy and the data were analyzed. The Kruskal-Wallis one-way analysis of variance (ANOVA) test was used to compare four sequential overlays and Spearman's rank correlation tests were used to evaluate the inter- and intraoperator reliability of the overlays obtained by the envelopment technique. Conclusion: Through our study, we conclude that the third and fourth cuts were the best among the four cuts and inter- and intraoperator reliability were found to be statistically significant at 5% level that is 95% confidence interval (P < 0.05). PMID:26816458

  3. Understanding the Properties of the BitTorrent Overlay

    Hamra, Anwar Al; Barakat, Chadi


    In this paper, we conduct extensive simulations to understand the properties of the overlay generated by BitTorrent. We start by analyzing how the overlay properties impact the efficiency of BitTorrent. We focus on the average peer set size (i.e., average number of neighbors), the time for a peer to reach its maximum peer set size, and the diameter of the overlay. In particular, we show that the later a peer arrives in a torrent, the longer it takes to reach its maximum peer set size. Then, we evaluate the impact of the maximum peer set size, the maximum number of outgoing connections per peer, and the number of NATed peers on the overlay properties. We show that BitTorrent generates a robust overlay, but that this overlay is not a random graph. In particular, the connectivity of a peer to its neighbors depends on its arriving order in the torrent. We also show that a large number of NATed peers significantly compromise the robustness of the overlay to attacks. Finally, we evaluate the impact of peer exchange...

  4. State of the art report on bituminized waste forms of radioactive wastes

    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  5. State of the art report on bituminized waste forms of radioactive wastes

    Kim, Tae Kook; Shon, Jong Sik; Kim, Kil Jeong; Lee, Kang Moo; Jung, In Ha


    In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs

  6. Synthesis document on the long time behavior of packages: operational document ''bituminous'' 2204

    This document is realized in the framework of the law of 1991 on the radioactive wastes management. The 2004 synthesis document on long time behavior of bituminous sludges packages is constituted by two documents, the reference document and the operational document. This paper presents the operational model describing the water alteration of the packages and the associated radioelements release, as the gas term source and the swelling associated to the self-irradiation and the bituminous radiolysis. (A.L.B.)

  7. Weld overlay cladding with iron aluminides

    Goodwin, G.M. [Oak Ridge National Lab., TN (United States)


    The author has established a range of compositions for these alloys within which hot cracking resistance is very good, and within which cold cracking can be avoided in many instances by careful control of welding conditions, particularly preheat and postweld heat treatment. For example, crack-free butt welds have been produced for the first time in 12-mm thick wrought Fe{sub 3}Al plate. Cold cracking, however, still remains an issue in many cases. The author has developed a commercial source for composite weld filler metals spanning a wide range of achievable aluminum levels, and are pursuing the application of these filler metals in a variety of industrial environments. Welding techniques have been developed for both the gas tungsten arc and gas metal arc processes, and preliminary work has been done to utilize the wire arc process for coating of boiler tubes. Clad specimens have been prepared for environmental testing in-house, and a number of components have been modified and placed in service in operating kraft recovery boilers. In collaboration with a commercial producer of spiral weld overlay tubing, the author is attempting to utilize the new filler metals for this novel application.

  8. Polygenic formation model of the planet's bituminous belts

    Dmitrievsky, A. N.; Balanyuk, I. E.


    In recent years, much attention has been paid to nontraditional hydrocarbon sources. Today the portion of nontraditional gas in the world extraction is 15% or 450 billion cubic meters, which hat makes up the volume of total gas exports from Russia. As is known, the easy-prospecting oil has been already found. The innovative technologies in geophysics, drilling, and excavation and the increased extraction coefficient expect further development and industrial compliance with these requirements. Based on calculations, the world oil reserves are now one trillion of stock tank barrels and one trillion barrels have been already extracted. The evergrowing demand for energy gives rise to the necessity of searching for and extracting more oil resources, and both these aspects are unique problems. The search for profitable petroleum deposits has become more and more difficult even in the leading companies. The increment of the world resources is a key vital question; therefore, the elaboration of criteria for the discovery of nontraditional deposits take on special significance in the economic respect. The authors are working out a conception that will be a guideline for future finding of the richest oil deposits in active geodynamic zones. For the first time, we suggest the polygenic formation model of the planet's bituminous belts.

  9. A process for the bituminization of radioactive wastes

    A process is described for the incorporation of sodium nitrate solutions in bitumen, with a view to the bituminization of radioactive wastes. This process has involved the development of a chemical process and its technological application. A double jacket reactor equipped with an anchor-type stirrer has been built. Sodium nitrate (NaNO3) solutions with sodium hydroxide (NaOH) are fed into the reactor simultaneously with a bitumen emulsion while heated oil is circulated through the double jacket. After all the water has evaporated, the mixture is ''simmered'' at 170/180 deg C for up to 5 hours in order to get a homogeneous product which will be suitable for final storage. The product contains small salt crystals (10/50 μm) and has high viscosity (200/2000 poise at 160 deg C and 12 rpm), so that the possibility of sedimentation is eliminated. In comparative experiments with molten bitumen, large salt aggregates, inhomogeneously distributed, make the product unsuitable. It has been found that NaOH is responsible for the polimerization of the bitumen, which raises its viscosity. The degree of polimerization depends on the NaOH concentration and ''simmering'' time and temperature. NaOH is added to NaNO3 in order to raise the mixture's viscosity and thereby prevent sedimentation

  10. The hydrogasification of lignite and sub-bituminous coals

    Bhatt, B.; Fallon, P. T.; Steinberg, M.


    A North Dakota lignite and a New Mexico sub-bituminous coal have been hydrogenated at up to 900°C and 2500 psi hydrogen pressure. Yields of gaseous hydrocarbons and aromatic liquids have been studied as a function of temperature, pressure, residence time, feed rates and H2/coal ratio. Coal feed rates in excess of 10 lb/hr have been achieved in the 1 in. I. D.×8 ft reactor and methane concentration as high as 55% have been observed. A four-step reaction model was developed for the production and decomposition of the hydrocarbon products. A single object function formulated from the weighted errors for the four dependent process, variables, CH4, C2H6, BTX, and oil yields, was minimized using a program containing three independent iterative techniques. The results of the nonlinear regression analysis for lignite show that a first-order chemical reaction model with respect to C conversion satisfactorily describes the dilute phase hydrogenation. The activation energy for the initial products formation was estimated to be 42,700 cal/gmole and the power of hydrogen partial pressure was found to be +0.14. The overall correlation coefficient was 0.83. The mechanism, the rate expressions, and the design curves developed can be used for scale-up and reactor design.

  11. Gasification of high ash, high ash fusion temperature bituminous coals

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang


    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in C. to C. range as well as in excess of C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  12. Fuel properties of bituminous coal and pyrolytic oil mixture

    Hamdan, Hazlin; Sharuddin, Munawar Zaman; Daud, Ahmad Rafizan Mohamad; Syed-Hassan, Syed Shatir A.


    Investigation on the thermal decomposition kinetics of coal-biooil slurry (CBS) fuel prepared at different ratios (100:0,70:30,60:40,0:100) was conducted using a Thermogravimetric Analyzer (TGA). The materials consisted of Clermont bituminous coal (Australia) and bio-oil (also known as pyrolytic oil) from the source of Empty Fruit Bunch (EFB) that was thermally converted by means of pyrolysis. Thermal decomposition of CBS fuel was performed in an inert atmosphere (50mL/min nitrogen) under non-isothermal conditions from room temperature to 1000°C at heating rate of 10°C/min. The apparent activation energy (Ea.) and pre-exponential factor (A) were calculated from the experimental results by using an Arrhenius-type kinetic model which first-order decomposition reaction was assumed. All kinetic parameters were tabulated based on the TG data obtained from the experiment. It was found that, the CBS fuel has higher reactivity than Clermont coal fuel during pyrolysis process, as the addition of pyrolytic oil will reduce the Ea values of the fuel. The thermal profiles of the mixtures showed potential trends that followed the characteristics of an ideal slurry fuel where high degradation rate is desirable. Among the mixture, the optimum fuel was found at the ratio of 60:40 of pyrolytic oil/coal mixtures with highest degradation rate. These findings may contribute to the development of a slurry fuel to be used in the vast existing conventional power plants.

  13. Design and Performance Evaluation of Service Overlay Networks Topologies

    Davide Adami


    Full Text Available Nowadays, Internet still lacks of an adequate support for QoS-sensitive applications, such as VoIP, Videoconference, and Video-on-Demand. To a large extent, this is due to the fact that Internet was originally designed to provide only a best-effort packet delivery service. In recent years, Service Overlay Networks (SONs have emerged as a profitable way to address these issues without changing the underlying infrastructure. In this paper, we analyze the topology design problem of a SON from a performance point of view. Since the analytical solution of the problem is computationally too complex, we compare the performance of a limited set of well-known topologies. Based on heuristics, we also propose three new traffic demand-aware overlay topologies. Through extensive simulations, we investigate the performance of the candidate overlay topologies in different network scenarios, taking into account overhead and accepted traffic between the overlay nodes.

  14. SPHERE: a scalable multicast framework in overlay networks


    This paper presents Sphere, a scalable multicast framework in overlay network. Sphere is a highly efficient, self-organizing and robust multicast protocol overlayed on the Internet. The main contributions of this paper are twofold. First, Sphere organizes the control topology of overlay network in two directions: horizontal and vertical. The horizontal meshes are used to locate and organize hosts in tracks, and the vertical meshes are used to manage the data paths between tracks. Second, Sphere balances stress and stretch of the overlay network by assigning hosts into different tracks and clusters. This structure distributes stress on the multicast trees uniformly, and meantime makes path stretch as small as possible.Simulations results show that Sphere can support multicast with large group size and has good performance on organizing meshes and building data delivery trees.

  15. Comparison between asphalt rubber and conventional mixtures in overlay design

    Fontes, Liseane P. T. L.; Trichês, Glicério; Pereira, Paulo A. A.; Pais, Jorge C.


    Asphalt modified with crumb rubber has been used to produce asphalt rubber mixtures for pavement overlays subjected to heavy loads and high temperatures. Under severe conditions, these mixtures are capable of resisting permanent deformations, having an extended fatigue life and resisting crack propagation in comparison to conventional ones. A laboratory research was conducted to determine the performance properties of overlays with asphalt rubber mixtures produced through wet processes using ...

  16. Augmenting reality in Direct View Optical (DVO) overlay applications

    Hogan, Tim; Edwards, Tim


    The integration of overlay displays into rifle scopes can transform precision Direct View Optical (DVO) sights into intelligent interactive fire-control systems. Overlay displays can provide ballistic solutions within the sight for dramatically improved targeting, can fuse sensor video to extend targeting into nighttime or dirty battlefield conditions, and can overlay complex situational awareness information over the real-world scene. High brightness overlay solutions for dismounted soldier applications have previously been hindered by excessive power consumption, weight and bulk making them unsuitable for man-portable, battery powered applications. This paper describes the advancements and capabilities of a high brightness, ultra-low power text and graphics overlay display module developed specifically for integration into DVO weapon sight applications. Central to the overlay display module was the development of a new general purpose low power graphics controller and dual-path display driver electronics. The graphics controller interface is a simple 2-wire RS-232 serial interface compatible with existing weapon systems such as the IBEAM ballistic computer and the RULR and STORM laser rangefinders (LRF). The module features include multiple graphics layers, user configurable fonts and icons, and parameterized vector rendering, making it suitable for general purpose DVO overlay applications. The module is configured for graphics-only operation for daytime use and overlays graphics with video for nighttime applications. The miniature footprint and ultra-low power consumption of the module enables a new generation of intelligent DVO systems and has been implemented for resolutions from VGA to SXGA, in monochrome and color, and in graphics applications with and without sensor video.

  17. Improving Resource Discovery in the Arigatoni Overlay Network

    Chand, Raphaël; Liquori, Luigi; Cosnard, Michel


    International audience Arigatoni is a structured multi-layer overlay network providing various services with variable guarantees, and promoting an intermittent participation to the virtual organization where peers can appear, disappear and organize themselves dynamically. Arigatoni mainly concerns with how resources are declared and discovered in the overlay, allowing global computers to make a secure, PKI-based, use of global aggregated computational power, storage, information resources,...

  18. Bituminous reference document: synthesis of knowledge on the long time behavior of bituminous packages; Dossier de reference bitume: synthese des connaissances sur le comportement a long terme des colis bitumes

    Sercombe, J.; Adenot, F.; Vistoli, P.P.; Parraud, S.; Riglet-Martial, C.; Gwinner, B.; Felines, I.; Tiffreau, C.; Libert, M


    This document is a synthesis of the knowledge acquired at the CEA on the behavior of bituminous packages. In this framework, the CEA studied bituminous packages in generic conditions of a package lifetime. The main factors, the evolution mechanisms and influential parameters have been determined and quantitative s simulation have been developed. After a description of the main initial bituminous packages characterizations, the evolutions in saturated and un-saturated environment are exposed. (A.L.B.)

  19. Overlay improvements using a real time machine learning algorithm

    Schmitt-Weaver, Emil; Kubis, Michael; Henke, Wolfgang; Slotboom, Daan; Hoogenboom, Tom; Mulkens, Jan; Coogans, Martyn; ten Berge, Peter; Verkleij, Dick; van de Mast, Frank


    While semiconductor manufacturing is moving towards the 14nm node using immersion lithography, the overlay requirements are tightened to below 5nm. Next to improvements in the immersion scanner platform, enhancements in the overlay optimization and process control are needed to enable these low overlay numbers. Whereas conventional overlay control methods address wafer and lot variation autonomously with wafer pre exposure alignment metrology and post exposure overlay metrology, we see a need to reduce these variations by correlating more of the TWINSCAN system's sensor data directly to the post exposure YieldStar metrology in time. In this paper we will present the results of a study on applying a real time control algorithm based on machine learning technology. Machine learning methods use context and TWINSCAN system sensor data paired with post exposure YieldStar metrology to recognize generic behavior and train the control system to anticipate on this generic behavior. Specific for this study, the data concerns immersion scanner context, sensor data and on-wafer measured overlay data. By making the link between the scanner data and the wafer data we are able to establish a real time relationship. The result is an inline controller that accounts for small changes in scanner hardware performance in time while picking up subtle lot to lot and wafer to wafer deviations introduced by wafer processing.

  20. Development of Design Software for Weld Overlay of Pressurizer

    Byeon, J. G.; Lee, J. B.; Park, K. S. [Doosan Heavy Industries and Construction Co., Seoul (Korea, Republic of)


    As a result of Primary Water Stress Corrosion Cracking (PWSCC) in alloy 600, leaks in dissimilar metal weld (DMW) of pressurizer nozzles were discovered recently in several US plants. The involved companies developed advanced repair techniques to prevent or repair PWSCC applying weld overlay procedures to dissimilar metal welds such as those between pipes and nozzles. Within 2 or 3 years, more than half of the nuclear power plants in Korea will have been in operation for more than 20 years. The weld overlay technology consists of overlay design, design and manufacturing of welding system and procedures. DMW zone in pressurized nozzles has different shapes and sizes. If shape and size of DMW zone in pressurized nozzles is different, the overlay design will be performed again. The welding system also will be designed and manufactured each types of nozzle. In order to minimize the similar works, related tool will be needed. From this background, the 3D Simulation software, dNOSS (doosan NSSS Overlay 3D Simulation Software), has been developed to apply full structural weld overlay for DMW

  1. Interplanetary Overlay Network Bundle Protocol Implementation

    Burleigh, Scott C.


    The Interplanetary Overlay Network (ION) system's BP package, an implementation of the Delay-Tolerant Networking (DTN) Bundle Protocol (BP) and supporting services, has been specifically designed to be suitable for use on deep-space robotic vehicles. Although the ION BP implementation is unique in its use of zero-copy objects for high performance, and in its use of resource-sensitive rate control, it is fully interoperable with other implementations of the BP specification (Internet RFC 5050). The ION BP implementation is built using the same software infrastructure that underlies the implementation of the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol (CFDP) built into the flight software of Deep Impact. It is designed to minimize resource consumption, while maximizing operational robustness. For example, no dynamic allocation of system memory is required. Like all the other ION packages, ION's BP implementation is designed to port readily between Linux and Solaris (for easy development and for ground system operations) and VxWorks (for flight systems operations). The exact same source code is exercised in both environments. Initially included in the ION BP implementations are the following: libraries of functions used in constructing bundle forwarders and convergence-layer (CL) input and output adapters; a simple prototype bundle forwarder and associated CL adapters designed to run over an IPbased local area network; administrative tools for managing a simple DTN infrastructure built from these components; a background daemon process that silently destroys bundles whose time-to-live intervals have expired; a library of functions exposed to applications, enabling them to issue and receive data encapsulated in DTN bundles; and some simple applications that can be used for system checkout and benchmarking.

  2. Surface Properties of Photo-Oxidized Bituminous Coals: Final report



    Natural weathering has a detrimental effect on the hydrophobic nature of coal, which in turn can influence clean-coal recovery during flotation. Few techniques are available that can establish the quality of coal surfaces and that have a short analysis time to provide input for process control. Luminescence emissions which can be quantified with an optical microscope and photometer system, are measurably influenced by degree of weathering as well as by mild storage deterioration. In addition, it has been shown that when vitrinite is irradiated with a relatively high intensity flux of violet- or ultraviolet- light in the presence of air, photo-oxidation of the surface occurs. The combination of measuring the change in luminescence emission intensity with degree of surface oxidation provided the impetus for the current investigation. The principal aim of this research was to determine whether clear correlations could be established among surface oxygen functionality, hydrophobicity induced by photo-oxidation, and measurements of luminescence intensity and alteration. If successful, the project would result in quantitative luminescence techniques based on optical microscopy that would provide a measure of the changes in surface properties as a function of oxidation and relate them to coal cleanability. Two analytical techniques were designed to achieve these goals. Polished surfaces of vitrain bands or a narrow size fraction of powdered vitrain concentrates were photo-oxidized using violet or ultraviolet light fluxes and then changes in surface properties and chemistry were measured using a variety of near-surface analytical techniques. Results from this investigation demonstrate that quantitative luminescence intensity measurements can be performed on fracture surfaces of bituminous rank coals (vitrains) and that the data obtained do reveal significant variations depending upon the level of surface oxidation. Photo-oxidation induced by violet or ultraviolet light

  3. Further beyond: registration and overlay control enhancements for optical masks

    Gorhad, Kujan; Cohen, Avi; Avizemer, Dan; Dmitriev, Vladimir; Beyer, Dirk; Degel, Wolfgang; Kirsch, Markus


    Mask registration control is one of the key performance specifications during the mask qualification process. It is becoming an important factor for yield improvement with the continuously tightening registration specs driven by tight wafer overlay specs. Understanding the impact of miss classified masks on the final wafer yield is gaining more and more attention, especially with the appearance of Multiple Patterning Technologies, where mask to mask overlay effect on wafer is heavily influenced by mask registration. ZEISS has established a promising closed loop solution implemented in the mask house, where the PROVE® system - a highly accurate mask registration and overlay metrology measurement tool, is being used to feed the RegC® - a registration and mask to mask overlay correction tool that can also accurately predict the correction potential in advance. The well-established RegC® process typically reaches 40-70% improvement of the mask registration/overlay error standard deviation. The PROVE® - RegC® closed loop solution has several advantages over alternative registration control methods apart of the mask re-write saving. Among the advantages is the capability to correct for pellicle mounting registration effects without the need to remove the pellicle. This paper will demonstrate improved method for enhanced mask to mask overlay control based on a new scheme of data acquisition and performance validation by the PROVE®. The mask registration data as well as additional mask information will be used to feed the RegC® correction process. Significantly improved mask to mask overlay correction results will be discussed and presented in details.

  4. Effects of salt content on leaching properties of synthetic bituminized wastes

    The leaching properties of soluble components (Na+, NO3−, and NO2−) in synthetic bituminized wastes with various characteristics, such as salt content, salt composition, and bitumen matrix, were quantitatively evaluated by means of an aqueous leaching test. Micropores were formed in the bituminized waste by the leaching of soluble salts. The penetrability of bitumen and the salt content affected the size and the shape of the micropores observed by scanning electron microscopy. The linear relationship between leaching fraction of the soluble components and square root of leaching time was observed, and the diffusion coefficient of the soluble component was determined by Fick's law. The diffusion coefficients of ionic species of interest were similar to each other. Moreover, the diffusion coefficient agreed among bituminized wastes with the same salt content, even if salt composition and bitumen matrix were different. The diffusion coefficient of the component was proportional to the salt content in the synthetic bituminized wastes. It was found that the salt content in the bituminized waste was one of the key factors to determine the diffusion coefficient. (author)

  5. Instructional geographic information science Map overlay and spatial abilities

    Tricot, Thomas Alexander, II

    The fundamental goal of this study is to determine if the complex spatial concept of map overlay can be effectively learned by young adolescents through the utilization of an instructional technique based within the foundations of Instructional Geographic Information Science (InGIScience). Percent correct and reaction times were the measures used to analyze the ability of young adolescents to learn the intersect, erase, and union functions of map overlay. The ability to solve for missing inputs, output, or function was also analyzed. Young adolescents of the test group scored higher percent correct and recorded faster reaction times than those of the control group or adults of the expert group by the end of the experiment. The intersect function of map overlay was more difficult in terms of percent correct and reaction time than the erase or union functions. Solving for the first or second input consistently resulted in lower percent correct and higher reaction times throughout the experiment. No overall performance differences were shown to exist between males and females. Results of a subjective "real-world" test also indicated learning by young adolescents. This study has shown that the practice of repetitive instruction and testing has proven effective for enhancing spatial abilities with regard to the map overlay concept. This study found that with practice, young adolescents can learn the map overlay concept and perform at levels equal to or greater than adults. This study has helped to answer the question of whether this development of spatial abilities is possible.

  6. Global market trade policy analysis for petroleum oils and oils obtained from bituminous minerals, crude

    Bagheri, F.


    Full Text Available This article is based on surveying the custom tariffs imposed on the world export market of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. We obtained the data according to the most updated available data provided online by UNCTAD and World Bank. The results indicate that none of the 142 countries in the world market of this product have imposed non-tariff trade barriers on the import of Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude. The developed countries and the countries with transition economies are the main world import partners. European Union, United States, China, Japan, South Korea, Canada, Singapore, Taiwan, Thailand, South Africa, Australia, Turkey, Brazil, Sweden and Belarus are the examples and have imposed low custom tariffs on Petroleum Oils and Oils Obtained from Bituminous Minerals, Crude.

  7. Ductile film delamination from compliant substrates using hard overlayers

    Cordill, M.J. [Erich Schmid Institute of Materials Science, Austrian Academy of Sciences (Austria); Marx, V.M.; Kirchlechner, C. [Max-Plank-Insitut für Eisenforschung GmbH, Düsseldorf (Germany)


    Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems. - Highlights: • Measuring the adhesion energies of ductile metal–polymer interfaces is difficult. • A Cu film would plastically deform under tensile strain without a Cr overlayer. • A Cr overlayer forces cracking and induces buckling between the crack fragments. • The adhesion energy of the metal–polymer interface can be measured.

  8. Structural Design of Pavement Overlays Based on Functional Parameters


    This paper reports a practical pavement overlay design methodbased on PCI (Pavement Condition Index). Current pavement investigation method (JTJ 073-96) is compared to the ASTM D 5340, which is the standard test method for airport pavement condition evaluation initially developed for US Air Force. The deficiency in the calculation of PCI based on field data in JTJ 073 is discussed. The proposed design method is compared to AASHTO overlay design method with good agreement. The paper concludes with an example illustrating how the existing pavement structural capacity is related to pavement distress survey results. The presented design method can be used in the design for overlay rehabilitation of pavements of highways, urban streets and airports.

  9. A Proactive Tree Recovery Mechanism for Resilient Overlay Multicast

    Poorna Satyanarayana B.


    Full Text Available Overlay multicast constructs a multicast delivery tree among end hosts. An important problem for making overlay multicast more dependable is how to recover from node departures in order to minimize the disruption of service to those affected nodes. In this paper, we propose a proactive tree recovery mechanism to make the overlay multicast resilient to these failures and unexpected events. The salient feature of the approach is that rescue plans for multiple non-leaf nodes can work together for their respective children when they fail or leave at the same time. Extensive simulations demonstrate that our proactive approach can recover from node departures much faster than reactive methods, while the quality of trees restored and the cost of recovery are reasonable

  10. Tuning carrier density at complex oxide interface with metallic overlayer

    Zhou, Y.; Shi, Y. J.; Jiang, S. W.; Yue, F. J.; Wang, P.; Ding, H. F.; Wu, D.


    We have systematically investigated the electronic transport properties of the LaAlO3/SrTiO3 interfaces with several different metal capping layers. The sheet carrier density can be tuned in a wide range by the metallic overlayer without changing the carrier mobility. The sheet carrier density variation is found to be linearly dependent on the size of metal work function. This behavior is explained by the mechanism of the charge transfer between the oxide interface and the metal overlayer across the LaAlO3 layer. Our results confirm the existence of a built-in electric field in LaAlO3 film with an estimated value of 67.7 eV/Å. Since the metallic overlayer is essential for devices, the present phenomena must be considered for future applications.

  11. Tensile Bond Strength of Latex-Modified Bonded Concrete Overlays

    Dubois, Cameron; Ramseyer, Chris


    The tensile bond strength of bonded concrete overlays was tested using the in-situ pull-off method described in ASTM C 1583 with the goal of determining whether adding latex to the mix design increases bond strength. One slab of ductile concrete (f'c > 12,000 psi) was cast with one half tined, i.e. roughened, and one half steel-troweled, i.e. smooth. The slab surface was sectioned off and overlay mixtures containing different latex contents cast in each section. Partial cores were drilled perpendicular to the surface through the overlay into the substrate. A tensile loading device applied a direct tensile load to each specimen and the load was increased until failure occurred. The tensile bond strength was then calculated for comparison between the specimens.

  12. Safety assessment for the bituminization facility of the medium-level waste

    The safety assessment for the home-made bituminization facility of the medium-level waste during hot test is made. The average external dose equivalent per month is 0.136 x 10-2 Sv. The radioactive substance released into the environment is much lower than the permissible limit. The danger of burning and exploding of the bituminized product is avoided because the operation temperature is controlled strictly below 170 C degree. The report also briefly describes the structural characteristic of the facility, the main process and radiation protection and safety measures

  13. Project and design of apparatus and equipment of pilot plant experimental bituminization line PS 44 EBO

    The modifications are described made in the design of major components of the pilot plant experimental bituminization line involving: the mixing equipment, the film rotor evaporator, the calciner, and various transport mechanisms for handling drums and containers. The difficulty and complexity of the problem which Kralovopolska strojirna Brno, the end supplier of the bituminization line, will have to tackle is evident mainly from the case of bridge cranes, which feed the line, and the full-portal gantry crane which handles the containers and drums at regional sites of radioactive waste disposal. (Z.M.)

  14. Installation in the A-1 plant of an experimental bituminization line by VUCHZ

    Following the termination of the experimental operation of the bituminization line at the Research Institute for Chemical Installations in Brno, the line was dismantled and transferred to the nucler power plant in Jaslovske Bohunice. The installation of the line, the layout of the assemblies are described and the results of tests with non-radioactive simulated wastes and actual radioactive wastes briefly described. An amount of 3.2 m3 of actual radioactive wastes from the V-1 nuclear power plant was processed in the tests. The results confirmed the suitability of bituminization for processing liquid radioactive wastes from WWER nuclear power plants. (Z.M.)

  15. Measured residual stresses in overlay pipe weldments removed from service

    Surface and throughwall residual stresses were measured on an elbow-to-pipe weldment that had been removed from the Hatch-2 reactor about a year after the application of a weld overlay. The results were compared with experimental measurements on three mock-up weldments and with finite-element calculations. The comparison shows that there are significant differences in the form and magnitude of the residual stress distributions. However, even after more than a year of service, the residual stresses over most of the inner surface of the actual plant weldment with an overlay were strongly compressive. 3 refs., 7 figs

  16. Flexible TWDM PON with WDM overlay for converged services

    Cheng, Ning


    This paper reviews recent developments of flexible TWDM PON (time- and wavelength-division multiplexed passive optical network) with pluggable transceivers for pay-as-you-grow deployment, load balancing, channel protection and power saving. Different architectures for TWDM PON with WDM (wavelength division multiplexed) overlay for converged broadband services are discussed and experimental results are presented for WDM overlay using low-cost self-seeded RSOA (reflective semiconductor optical amplifiers). Challenging issues and possible solutions for future evolution toward software defined flexible PONs (FlexPONs) are also discussed with respect to dynamic lambda flow, elastic bandwidth and flexible reach.

  17. Implementing a Trust Overlay Framework for Digital Ecosystems

    Malone, Paul; McGibney, Jimmy; Botvich, Dmitri; McLaughlin, Mark

    Digital Ecosystems, being decentralised in nature, are inherently untrustworthy environments. This is due to the fact that these environments lack a centralised gatekeeper and identity provider. In order for businesses to operate in these environments there is a need for security measures to support accountability and traceability. This paper describes a trust overlay network developed in the OPAALS project to allow entities participating in digital ecosystems to share experience through the exchange of trust values and to leverage on this network to determine reputation based trustworthiness of unknown and initially untrusted entities. An overlay network is described together with sample algorithms and a discussion on implementation.

  18. Scalable, Self-Healing, and Self-Optimizing Routing Overlays

    Brun, Olivier; Hassan, Hassan; Vallet, Josselin


    After Internet routing was shown in a number of classic measurement papers to result in paths that are sub-optimal with respect to a number of metrics, routing overlays were proposed as a method for improving performance, without the need to re-engineer the underlying network. In this paper, we present SMART, a self-healing, self-optimizing and highly scalable routing overlay, which has a number of advantages with respect to existing solutions. First, SMART can run with off-the-shelf applicat...

  19. 8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials

    Partl, Manfred


    This work presents the results of RILEM TC 237-SIB (Testing and characterization of sustainable innovative bituminous materials and systems). The papers have been selected for publication after a rigorous peer review process and will be an invaluable source to outline and clarify the main directions of present and future research and standardization for bituminous materials and pavements. The following topics are covered: - Characterization of binder-aggregate interaction - Innovative testing of bituminous binders, additives and modifiers - Durability and aging of asphalt pavements - Mixture design and compaction analysis - Environmentally sustainable materials and technologies - Advances in laboratory characterization of bituminous materials - Modeling of road materials and pavement performance prediction - Field measurement and in-situ characterization - Innovative materials for reinforcement and interlayer systems - Cracking and damage characterization of asphalt pavements - Rec...

  20. Noise Reduction Properties of an Experimental Bituminous Slurry with Crumb Rubber Incorporated by the Dry Process

    Moisés Bueno


    Full Text Available Nowadays, cold technology for asphalt pavement in the field of road construction is considered as an alternative solution to conventional procedures from both an economic and environmental point of view. Among these techniques, bituminous slurry surfacing is obtaining an important role due to the properties of the obtained wearing course. The functional performance of this type of surfaces is directly related to its rough texture. Nevertheless, this parameter has a significant influence on the tire/road noise generation. To reduce this undesirable effect on the sound performance, new designs of elastic bituminous slurries have been developed. Within the FENIX project, this work presents the acoustical characterization of an experimental bituminous slurry with crumb rubber from wasted automobile tires incorporated by the dry process. The obtained results show that, under controlled operational parameters, the close proximity sound levels associated to the experimental slurry are considerably lower than those emitted by a conventional slurry wearing course. However, after one year of supporting traffic loads and different weather conditions, the evaluated bituminous slurry, although it conserves the original noise reduction properties in relation to the conventional one, noticeably increases the generated sound emission. Therefore, it is required to continue improving the design of experimental surfaces in order to enhance its long-term performance.

  1. Development and operation experience from pilot-plant for bituminization of liquid radioactive wastes (UBD-200)

    The results are given for investigations of liquid radioactive wastes bituminization on the pilot-plant of continious operation. The bituminization process is divided into two stages. On the first stage salts with definite moisture content are obtained. On the second stage, wet salts are mixed with melted bitumen. In this process the salts are finally dryed and bitumen compound produced is transported towards the discharge assembly. Design of the dryer and mixer is described and their technical parameters are given. Salt-bitumen compound is discharged in moulding bogies with volume of 0.5 m3. After hardening, salt-bitumen compound blocks are removed for burial. Average composition of liquid radioactive wastes coming for solidification is given. Dependences of the salt-bitumen compound characteristics on the parameters of the technological process of bituminization are given as well as the results of analysis of filling of compound by salts at the block height of 0.3 m. It is shown that division of the bituminization process into two stages do not affect on the chemical stability of compound. (I.T.)

  2. Towards an Accurate Stress Dependant Time & Frequency Domain VE Response Model for Bituminous Binders

    Woldekidan, M.F.; Huurman, M.; Pronk, A.C.


    Linear viscoelastic properties of bituminous binders for short loading times are analyzed using dynamic mechanical analysis methods. Dynamic Shear Rheometer (DSR) test with parallel plate (PP) configuration is widely used for this purpose. Due to the complex stress distribution over the cross-sectio

  3. Bituminization system of low level liquid waste in Genkai Nuclear Power Plant

    The bituminization system for low level radioactive liquid wastes has such advantages as its volume reduction is 6 to 10 times higher than the cementing systems, and the exuding ratio of radioactive nuclides from bituminized body into sea water is smaller, because the solids containing radioactive nuclides are solidified into oily bitumen which is very water repellent. Therefore, Genkai No.2 reactor plant has adopted the batch bituminization system, the main equipment of which being a drum mixer. This equipment has the capacity of treating 35 m3 of drain from the machines (boron 21,000 ppm) yearly, mainly composed of boric acid, and 85 m3 of floor drain/laundry drain yearly (solids 1.1 wt.%). This paper describes the outline of the system, the improvement of the installation, operating method, operation control, and the results of cold and hot operations. At the beginning of the trial operation, the concentrated laundry drain from No.1 reactor during the regular inspection was bituminized, and the concentrated sodium borate solution from No.2 reactor was treated since July, 1980. These results show the good volume reduction, condensate-processing capability, mixer controllability and mixer decontamination efficiency. (Wakatsuki, Y.)

  4. Effect of bituminous coal properties on carbon dioxide and methane high pressure sorption

    Weishauptová, Zuzana; Přibyl, Oldřich; Sýkorová, Ivana; Machovič, Vladimír


    Roč. 139, JAN 1 (2015), s. 115-124. ISSN 0016-2361 Institutional support: RVO:67985891 Keywords : bituminous coal * sorption capacity * maceral composition * Upper Silesian Coal Basin Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.520, year: 2014

  5. Dynamic adaptable overlay networks for personalised service delivery

    Mathieu, B.; Stiemerling, M.; Soveri, M.C.; Galis, A.; Jean, K.; Ocampo, R.; Lai, Z.; Kampmann, M.; Tariq, M.A.; Balos, K.; Ahmed, O.K.; Busropan, B.J.; Prins, M.J.


    Overlay Networks have been designed as a promising solution to deliver new services via the use of intermediate nodes, acting as proxies or relays. This concept enables to hide the heterogeneity and variability of the underlying networks. In the Ambient Networks (ANs) project, the objectives are to

  6. Residual stress measurement in 304 stainless steel weld overlay pipes

    Welding overlay repair (WOR) is commonly employed to rebuild piping systems suffering from intergranular stress corrosion cracking (IGSCC). To understand the effects of this repair, it is necessary to investigate the distribution of residual stresses in the welding pipe. The overlay welding technique must induce compressive residual stress at the inner surface of the welded pipe to prevent IGSCC. To understand the bulk residual stress distribution, the stress profile as a function of location within wall is examined. In this study the full destructive residual stress measurement technique -- a cutting and sectioning method -- is used to determine the residual stress distribution. The sample is type 304 stainless steel weld overlay pipe with an outside diameter of 267 mm. A pipe segment is cut from the circular pipe; then a thin layer is removed axially from the inner to the outer surfaces until further sectioning is impractical. The total residual stress is calculated by adding the stress relieved by cutting the section away to the stress relieved by axially sectioning. The axial and hoop residual stresses are compressive at the inner surface of the weld overlay pipe. Compressive stress exists not only at the surface but is also distributed over most of the pipe's cross section. On the one hand, the maximum compressive hoop residual stress appears at the pipe's inner surface. The thermal-mechanical induced crack closure from significant compressive residual stress is discussed. This crack closure can thus prevent IGSCC very effectively

  7. A Many-Core Overlay for High-Performance Embedded Computing on FPGAs

    Véstias, Mário; Neto, Horácio


    In this work, we propose a configurable many-core overlay for high-performance embedded computing. The size of internal memory, supported operations and number of ports can be configured independently for each core of the overlay. The overlay was evaluated with matrix multiplication, LU decomposition and Fast-Fourier Transform (FFT) on a ZYNQ-7020 FPGA platform. The results show that using a system-level many-core overlay avoids complex hardware design and still provides good performance resu...

  8. Throughput and Packet Delay Analysis of the Intermittent DCF for Overlay Access Networks

    Adamis, Athanassios V.; Maliatsos, Konstantinos N.; Constantinou, Philip

    Overlay Access Technology can compensate for the spectrum underutilization problem by exploiting Cognitive Radios capabilities. MAC design is an important aspect of Overlay Access research. In this paper we present the overlay access environment and the challenges it poses to MAC design. Then, we propose the use of a modified Distributed Coordination Function as the MAC protocol for distributed Overlay Access networks. The resulted Intermittent DCF performs with robustness in the demanding overlay access environment, which is characterized by frequent spectrum scan procedure interruptions and low achievable transmission rates. The most recent DCF Markov Chain Model is extended in order to include the overlay operation modifications. Our extension concerns the slot duration expectations calculation which, in the overlay environment, have not constant values but depend on overlay operation parameters. Using the analytical model we evaluate the performance of the DCF under the effect of certain overlay access parameters. The new analytical model predictions are validated with simulations, and are found to accurately capture many interesting features of the overlay operation. Our model can be used in feasibility studies of realistic overlay scenarios and in admission control algorithms of QoS enabled distributed overlay access networks that engage the Intermittent DCF.

  9. Testing of the possibility for the use of BEWAG-coal cinder in bituminous supporting layers of asphalt fastening

    Ueckert, H.W.


    In order to develop further use of coal cinder granulate the suitability of that granulate has been tested for use as an additional material for bituminous supporting layers. Results: (1) The granulate can be used for asphalt supporting layers Type B according TVT 72. (2) The granulation scope 0/5 mm is recommended. (3) The granular share of the mineral mixture can amount up to 30% of weight. (4) Standard-Bitumen B 65 can be used as bituminous binders. (5) The optimum consistence of the bituminous materials has to be found according of an aptitude test.

  10. Modeling the dynamical interaction between epidemics on overlay networks

    Marceau, Vincent; Hébert-Dufresne, Laurent; Allard, Antoine; Dubé, Louis J


    Epidemics seldom occur as isolated phenomena. Typically, two or more viral agents spread within the same host population and may interact dynamically with each other. We present a general model where two viral agents interact via an immunity mechanism as they propagate simultaneously on two networks connecting the same set of nodes. Exploiting a correspondence between the propagation dynamics and a dynamical process performing progressive network generation, we develop an analytic approach that accurately captures the dynamical interaction between epidemics on overlay networks. The formalism allows for overlay networks with arbitrary joint degree distribution and overlap. To illustrate the versatility of our approach, we consider a hypothetical delayed intervention scenario in which an immunizing agent is disseminated in a host population to hinder the propagation of an undesirable agent (e.g. the spread of preventive information in the context of an emerging infectious disease).

  11. On-demand Overlay Networks for Large Scientific Data Transfers

    Ramakrishnan, Lavanya [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Guok, Chin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jackson, Keith [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kissel, Ezra [Univ. of Delaware, Newark, DE (United States); Swany, D. Martin [Univ. of Delaware, Newark, DE (United States); Agarwal, Deborah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)


    Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.

  12. Flutter Analysis of the Shuttle Tile Overlay Repair Concept

    Bey, Kim S.; Scott, Robert C.; Bartels, Robert E.; Waters, William A.; Chen, Roger


    The Space Shuttle tile overlay repair concept, developed at the NASA Johnson Space Center, is designed for on-orbit installation over an area of damaged tile to permit safe re-entry. The thin flexible plate is placed over the damaged area and secured to tile at discreet points around its perimeter. A series of flutter analyses were performed to determine if the onset of flutter met the required safety margins. Normal vibration modes of the panel, obtained from a simplified structural analysis of the installed concept, were combined with a series of aerodynamic analyses of increasing levels of fidelity in terms of modeling the flow physics to determine the onset of flutter. Results from these analyses indicate that it is unlikely that the overlay installed at body point 1800 will flutter during re-entry.

  13. Rutting Resistance of Asphalt Overlay with Multilayer Wheel Tracking Test

    LIAO Weidong; CHEN Zheng; WU Shaopeng; MO Liantong; LIU Gang


    The rutting resistance of multilayer asphalt overlay was researched by using laboratory wheel tracking test. The effects of loading level and test temperature on rutting resistance of asphalt overlay structure were evaluated by means of multilayer specimens .In comparison with multilayer tests, standard specimens of various layers were also conducted to evaluate the rutting resistance. Experimental results indicated that the test temperature and applied load have a significant effect on rutting resistance of asphalt concrete. Higher test temperature and heavier applied load resulted in higher rut depths. In addition, the mutilayer wheel tracking test has been demonstrated to be a more reasonable solution in evaluation on rutting resistance of asphatt pavement structure beasuse it reflects the cumulative permanent deformation in all of asphalt layers.

  14. CLIO — A Cross-Layer Information Service for Overlay Network Optimization

    Haage, Dirk; Holz, Ralph; Niedermayer, Heiko; Laskov, Pavel

    New overlay-based services aim to provide properties like resilience, availability or QoS. To achieve this, automatic organization and optimization is required, which again demands accurate information on the network. Collecting and exchanging this data has a significant impact on the network, especially if several overlays are used on the same host. In this paper, we provide a survey of the current state of the art and identify challenges which must be addressed in order for new overlay-based services to be successful. We present our own solution CLIO, a cross-layer information service for overlays. CLIO provides information for the automatic creation and optimization of overlays. The service supports multiple overlays on the same node, the provided information is overlay-independent, and collected information is reused.

  15. Testing and analysis for weld overlay repair of thinned class 2 and 3 ferritic piping

    Sections III and XI of the ASME Code do not prohibit use of external weld overlays to repair internal wall thinning. Neither, however, do these ASME Code Sections provide specific guidance for weld overlay repair installation. this lack of specific guidance has resulted in broad differences of opinion as to the viability of weld overlay repairs. In order to resolve these differences of opinion, several weld overlay repairs have been installed and evaluated. Thee overlay repairs were installed on carbon steel piping coupons using E7018 electrodes. A variety of flaw sizes, weld installation parameters, and weld configurations were employed. The repair areas were tested, and the test results were used to develop proposed rules for incorporation into Section XI of the ASME Code. Finite element analysis was performed to benchmark the test results, and to provide guidance for applying weld overlay repairs in the field. These tests demonstrate that external weld overlay is a viable repair alternative for internal wall thinning

  16. Virtual Private Overlays: Secure Group Commounication in NAT-Constrained Environments

    Wolinsky, David Isaac; Choi, Tae Woong; Boykin, P Oscar; Figueiredo, Renato


    Structured P2P overlays provide a framework for building distributed applications that are self-configuring, scalable, and resilient to node failures. Such systems have been successfully adopted in large-scale Internet services such as content delivery networks and file sharing; however, widespread adoption in small/medium scales has been limited due in part to security concerns and difficulty bootstrapping in NAT-constrained environments. Nonetheless, P2P systems can be designed to provide guaranteed lookup times, NAT traversal, point-to-point overlay security, and distributed data stores. In this paper we propose a novel way of creating overlays that are both secure and private and a method to bootstrap them using a public overlay. Private overlay nodes use the public overlay's distributed data store to discover each other, and the public overlay's connections to assist with NAT hole punching and as relays providing STUN and TURN NAT traversal techniques. The security framework utilizes groups, which are cr...

  17. A comparative study of overlay generation methods in bite mark analysis

    Mihir Khatri


    Full Text Available Aim: To evaluate the best method of overlay generation out of the three methods, i.e., manual, photocopying, and computer assisted method. Materials and Methods: Impressions of maxillary and mandibular arches of 25 individuals participating in the study were made and dental study models were prepared. Overlay production was done by manual, photocopying, and computer assisted methods. Finally, the overlays obtained by each method were compared. Results: Kruskal Wallis ANOVA H test was used for the comparison of manual, photocopying, and computer assisted overlay generation methods. H value being highest in case of computer assisted overlays, thus, making it the best method of overlay generation out of the three methods. Conclusion: We conclude that the method of computer assisted overlay generation is the best among the three methods used in our study.

  18. A Novel Overlay IDS For Wireless Sensor Networks

    Saha, Sumanta; Islam, Md. Safiqul; Hossen, Md. Sakhawat; Mamun, Mohammad Saiful Islam


    Wireless Sensor Network (WSN) consists of low cost sensor nodes which cannot afford to implement sophisticated security system in it. That is why intrusion detection architecture for WSN is considerably different and difficult to implement. Most of the current implementations are based on exchanging anomaly signals among the leaf level sensors resulting in too much power consumption. We propose a novel architecture for Intrusion Detection System (IDS) in WSN based on Hierarchical Overlay Desi...

  19. Intelligent FDSS Overlay on GSM System (Uplink Analysis)

    Haro-Ariet, L. D.; M. Calvo-Ramon; B. Taha-Ahmed


    The overlay of an intelligent frequency diversity spread spectrum system (FDSS) on the (GSM) system is studied. The uplink capacity of both systems is given using a model of 36 hexagonal macrocells. Performance of GSM and FDSS users is investigated. An original GSM system with 48 users/macrocell can be substituted by a mixed system, which has GSM system capacity of 48 users/macrocell and FDSS system capacity of 128 users/macrocell.

  20. Toward a scalable and collaborative network monitoring overlay

    Castro, Vasco; Carvalho, Paulo; Lima, Solange


    This paper presents ongoing work toward the definition of a new network monitoring model which resorts to a cooperative interaction among measurement entities to monitor the quality of network services. Exploring (i) the definition of representative measurement points to form a network monitoring overlay; (ii) the removal of measurement redundancy through composition of metrics; and (iii) a simple active measurement methodology, the proposed model aims to contribute to a scalable, robust a...

  1. Multipair Massive MIMO Relaying with Pilot-Data Transmission Overlay

    Pan, Leyuan; Dai, Yongyu; Xu, Wei; Dong, Xiaodai


    We propose a pilot-data transmission overlay scheme for multipair massive multiple-input multiple-output (MIMO) relaying systems employing either half- or full-duplex (HD or FD) communications at the relay station (RS). In the proposed scheme, pilots are transmitted in partial overlap with data to decrease the channel estimation overhead. The RS can detect the source data with minimal destination pilot interference by exploiting the asymptotic orthogonality of massive MIMO channels. Then pilo...

  2. Overlay mark optimization using the KTD signal simulation system

    Marchelli, Anat; Gutjahr, Karsten; Kubis, Michael; Sparka, Christian; Ghinovker, Mark; Navarra, Alessandra; Widmann, Amir


    As the overlay performance and accuracy requirements become tighter, the impact of process parameters on the target signal becomes more significant. Traditionally, in order to choose the optimum overlay target, several candidates are placed in the kerf area. The candidate targets are tested under different process conditions, before the target to be used in mass production is selected. The varieties of targets are left on the mass production mask and although they will not be used for overlay measurements they still consume kerf real estate. To improve the efficiency of the process we are proposing the KTD (KLA-Tencor Target Designer). It is an easy to use system that enables the user to select the optimum target based on advanced signal simulation. Implementing the KTD in production is expected to save 30% of kerf real estate due to more efficient target design process as well as reduced engineering time. In this work we demonstrate the capability of the KTD to simulate the Archer signal in the context of advanced DRAM processes. For several stacks we are comparing simulated target signals with the Archer100 signals. We demonstrate the robustness feature in the KTD application that enables the user to test the target sensitivity to process changes. The results indicate the benefit of using KTD in the target optimization process.

  3. The Development of An Analytical Overlay Design Procedure

    Djunaedi Kosasih


    Full Text Available Pavement structural evaluation using pavement modulus values resulting from back calculation process on non-destructive deflection data has been adopted to quantify objectively the conditions of existing pavements under various traffic loading and environmental conditions. However, such an advanced technique is not yet followed widely by advances in analytical overlay design procedures. One possible reason is perhaps due to its requirement to perform complex computations. A new module of computer program BackCalc has been developed to do that task based on the allowable maximum deflection criterion specified by the Asphalt Institute’83. The rationale is that adequate overlay thickness will be computed by iteration to result in theoretical maximum deflection that closely matches against the specified allowable maximum deflection. This paper outlines the major components of the program module illustrated by using a practical example. The overlay thickness obtained was found to be comparable with that of the known AASHTO’93 method

  4. Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM

    Pariza Kamboj


    Full Text Available Many crucial applications of MANETs like the battlefield, conference and disaster recovery defines the needs for group communications either one-to-many or many-to-many form. Multicast plays an important role in bandwidth scarce multihop mobile ad hoc networks comprise of limited battery power mobile nodes. Multicast protocols in MANETs generate many controls overhead for maintenance of multicast routingstructures due to frequent changes of network topology. Bigger multicast tables for the maintenance of network structures resultsin inefficient consumption of bandwidth of wireless links andbattery power of anemic mobile nodes, which in turn, pose thescalability problems as the network size is scaled up. However,many MANET applications demands scalability from time to time. Multicasting for MANETs, therefore, needs to reduce the state maintenance. As a remedy to these shortcomings, this paper roposes an overlay multicast protocol on application layer. In the proposed protocol titled “Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM” the network nodes construct overlay hierarchical framework to reduce the protocols states and constrain their distribution within limited scope. Based on zone around each node, it constructs a virtual structure at application layer mapped with the physical topology at network layer, thus formed two levels of hierarchy. The concept of two level hierarchies reduces the protocol state maintenance and hence supports the vertical scalability. Protocol depends on the location information obtained using a distributed location service, which effectively reduces the overhead for route searching and updating the source based multicast tree.

  5. Perceived effects of coloured overlays on reading material in persons with albinism

    N. T. Makgaba


    Full Text Available Persons with albinism often complain of glare when reading. They may therefore benefit from coloured filter overlays just as they benefit from tinted lenses. The purpose of this study was to assess the effectof coloured overlays on print perception in persons with oculocutaneous albinism (OCA.   Fifty subjects were included in this study, their ages ranged from 12 to 31 years with a mean of 16.12 years (SD = ± 4.56 years.  Following refraction and subsequent compensation for refractive errors, subjective perception of print was examined with the subject looking at the Wilkins® reading rate test chart with and without colored filter overlay/s.  The subjects were asked to respond to questions previously used in a questionnaire by Wilkins (2001. The percentage frequencies of positive (beneficial responses were used to decide whether or not a particular overlay would enhance reading performance.  McNemar’s test was used to establish significant differences between responses to questions without and with overlays. All single overlays gave greater percentages of positive responses (92.0-97.2% than without overlay (85.2%.  The single overlay that provided the highest positive responses was blue (97.2% and the least was purple (92.0%. All double overlays, except grey/grey (82.0% gave greater positive responses than without overlay (85.2%. Aqua/blue gave the greatest positive responses (possible benefits (97.2%, followed by rose/rose (96.8%.  Comparing the responses without overlay with single and double overlays, the difference in responses to the five questions was only significant (p < 0.05 with regard to brightness of the surface. The results suggest that overlays provided a more glare-free reading surface than without an overlay. It was, therefore concluded that the best advantage of the coloured overlays was in glare reduction.  Although this study showed that there were more subjects who preferred single blue and aqua/blue double

  6. Transformism in Alberta: The Environmental Political Economy of the Bituminous Sands

    Katz-Rosene, Ryan

    This thesis attempts to help establish environmental political economy as a viable academic field while providing an example of work in the discipline. It offers an analysis of societal processes resulting in the co-optation and/or neutralization of critical environmentalist ideas. Using Alberta's bituminous sands as a case study, and a Gramsci-influenced eco-Marxist theory as a foundation, the thesis argues that the term 'environmental transformism' (inspired by the Gramscian term trasformismo) is helpful in describing and framing such processes. Accordingly, the ensuing chapters provide an analysis of why environmental transformism is happening in Alberta, and demonstrate how this mechanism works at protecting the status quo from threatening ideologies, thereby consolidating neoliberal capitalism. A concluding argument discusses the inherent dangers posed to society by the transformism of certain environmental subjectivities. The thesis begins by introducing the contentious social and environmental issues surrounding the development of the bituminous sands.

  7. Radiation-chemical transformation of synthetic oil from oil-bituminous rock

    Full text : Like as test subject was used synthetic oil from oil-bituminous rocks of Balakhany deposit. The regularities of synthetic oils radiation-chemical transformations were studied. Laboratory researches were carried out in an interval of absorbed dose 43-216 kGr and dose rate 0.5 Gr/s. Concentration, radiation-chemical yields of the received gases in the various absorbed doses were established. Results of researches allow to estimate possibility use of oil products received from synthetic oil for isolation of radioactive sources from environment. The purpose of the given work is research of radiation stability of synthetic oil from bituminous rock. Results of such researches will allow to estimate possibility of production different purpose oil products from synthetic oil in a radiation-chemical way and also use of these materials for isolation of radioactive sources from environment

  8. Long-term behavior of bituminized waste: modelling of auto-irradiation and leaching

    During interim storage, the main evolution factor of the bituminized wastes is radiolysis under auto-irradiation, while in deep disposal conditions, after radioactive decrease, site resaturation with water, and container corrosion, the main factor of evolution is leaching by water. This paper presents two models, designed to describe respectively radiolytic gas evacuation, and bituminized waste alteration under leaching. The first model is based on the integration of simple descriptions of gas production by radiolysis, gas diffusive transport, bubble nucleation and ripening, and bubble transport under buoyancy and viscosity. The second model is based on simple descriptions of water adsorption and solubilization at the surface, water diffusion into the matrix, water uptake by the most soluble salts, salt grain swelling and alteration of matrix waterproofing, diffusive transport of salts out of the waste. Copyright (2001) Material Research Society

  9. A Method to Estimate the Dynamic Displacement and Stress of a Multi-layered Pavement with Bituminous or Concrete Materials

    LU, ZHENG; Yao, Hailin; Zhang, JingBo


    In this research work, a method to estimate the dynamic characteristics of a multilayered pavement with bituminous or concrete materials is proposed. A mechanical model is established to investigate the dynamic displacement and stress of the multi-layered pavement structure. Both the flexible and the rigid pavements, corresponding to bituminous materials and concrete materials, respectively, are studied. The theoretical solutions of the multi-layered pavement structure are deduced considering...

  10. Is Atomic Force Microscopy suited as Tool for fast Screening of Bituminous Materials? An Inter-laboratory Comparison Study

    Nahar, S.N.; Dillingh, B.; Erkens, S.M.J.G.; Schmets, A. J. M.; Fischer, H.R.; Scarpas, A.; Schitter, G.


    Bituminous binders are known to have microstructures at typical length scales of micrometers. This microstructure can be probed with Atomic Force Microscopy (AFM). Now that worldwide several research groups are reporting AFM results on bitumen, it is becoming important to improve the understanding of the reproducibility and objectivity of the technique for studying bituminous samples. When reproducibility and stability are proven, AFM can be a tool for asphalt professionals to rapidly screen ...

  11. Modelling the quasi-static behaviour of bituminous material using a cohesive zone model

    Tabakovic, Amir; Karac, Aleksandar; Ivankovic, Alojz; Gibney, Amanda; McNally, Ciaran; Gilchrist, M. D.


    This paper investigates the applicability of a cohesive zone model for simulating the performance of bituminous material subjected to quasistatic loading. The Dugdale traction law was implemented within a finite volume code in order to simulate the binder course mortar material response when subjected to indirect tensile loading. A uniaxial tensile test and a threepoint bend test were employed to determine initial stress-strain curves at different test rates and the cohesive zone parameters (...

  12. Influence of properties of bituminous binders on the strength of formed coke

    Sharma, Ashok K.; Das, Bani P.; Tripathi, Prem S.M. [Central Fuel Research Institute, P.O. FRI-828108, Dhanbad (India)


    The role of different chemical characteristics (coking value, quinoline insolubles, elemental composition, {beta}-resin, toluene solubles) of various coal tar- and petroleum-based bituminous binders, such as heavy fraction of HTC tar, processed LTC tar, pitch and asphalt as also the mixed binder in controlling the strength of formed coke made from char prepared from non-coking Chirimiri coal and coke breeze (prepared after carbonising Jharia coal), respectively, has been studied in some detail. The objective was to investigate as to whether and how the properties of these bituminous binders govern the strength of formed coke. It is found that these properties of the binders do play significantly important role in controlling the strength of formed coke both during curing and carbonisation. These parameters of the binders are found to be closely related with their atomic C/H ratios. Notwithstanding the varying composition of the binders of different origin, be they coal tar or petroleum based, the atomic C/H ratio seems to be the most important characteristics of the bituminous binders, upon which the strength of formed coke depends predominantly. This also holds true when mixed binders were used. The results show that at a C/H ratio of about 1, the strength of the briquettes either on curing or on carbonising remains almost similar and that strong cured briquettes can be produced by using a bituminous binder with a C/H ratio less than 1, whilst for obtaining strong carbonised briquettes, binders with C/H ratio greater than 1 are preferable.

  13. Slagging behavior of upgraded brown coal and bituminous coal in 145 MW practical coal combustion boiler

    Akiyama, Katsuya; Pak, Haeyang; Takubo, Yoji [Kobe Steel, Ltd, Kobe (Japan). Mechanical Engineering Research Lab.; Tada, Toshiya [Kobe Steel, Ltd, Takasago (Japan). Coal and Energy Technology Dept.; Ueki, Yasuaki [Nagoya Univ. (Japan). Energy Science Div.; Yoshiie, Ryo; Naruse, Ichiro [Nagoya Univ. (Japan). Dept. of Mechanical Science and Engineering


    The purpose of this study is to quantitatively evaluate behaviors of ash deposition during combustion of Upgraded Brown Coal (UBC) and bituminous coal in a 145 MW practical coal combustion boiler. A blended coal consisting 20 wt% of the UBC and 80 wt% of the bituminous coal was burned for the combustion tests. Before the actual ash deposition tests, the molten slag fractions of ash calculated by chemical equilibrium calculations under the combustion condition was adopted as one of the indices to estimate the tendency of ash deposition. The calculation results showed that the molten slag fraction for UBC ash reached approximately 90% at 1,523 K. However, that for the blended coal ash became about 50%. These calculation results mean that blending the UBC with a bituminous coal played a role in decreasing the molten slag fraction. Next, the ash deposition tests were conducted, using a practical pulverized coal combustion boiler. A water-cooled stainless-steel tube was inserted in locations at 1,523 K in the boiler to measure the amount of ash deposits. The results showed that the mass of deposited ash for the blended coal increased and shape of the deposited ash particles on the tube became large and spherical. This is because the molten slag fraction in ash for the blended coal at 1,523 K increased and the surface of deposited ash became sticky. However, the mass of the deposited ash for the blended coal did not greatly increase and no slagging problems occurred for 8 days of boiler operation under the present blending conditions. Therefore, appropriate blending of the UBC with a bituminous coal enables the UBC to be used with a low ash melting point without any ash deposition problems in a practical boiler.

  14. Microstructural self-healing of bituminous materials: Combined experimental and numerical study

    Pauli, A; Schmets, A. J. M.; Kasbergen, C.; Varveri, K.; Scarpas, A.


    Bituminous materials form a class of materials that possess the intrinsic ability to selfheal. This self-healing capability is evidenced by the observation that the service life of these materials ‘in the field’ exceeds the service life as predicted by standard mechanical laboratory tests. This mismatch between laboratory prediction and field service life is usually accounted for by applying a shift or healing factor. In this contribution we demonstrate a model that is based on the observatio...

  15. The microstructure of petroleum vacuum residue films for bituminous concrete: a microscopy approach.

    Sourty, E D; Tamminga, A Y; Michels, M A J; Vellinga, W-P; Meijer, H E H


    Selected carbon-rich refinery residues ('binders') mixed with mineral particles can form composite materials ('bituminous concrete') with bulk mechanical properties comparable to those of cement concrete. The microstructural mechanism underlying the remarkable composite properties has been related to the appearance of a rigid percolating network consisting of asphaltenes and mineral particles [Wilbrink M. et al. (2005) Rigidity percolation in dispersions with a structured visco-elastic matrix. Phys. Rev. E71, 031402]. In this paper, we explore the microstructure of thin binder films of varying thickness with a number of microscopic characterization techniques, and attempt to relate the observed microstructure to the distinctive mechanical behaviour. Two binders, only one of which has been proven to be suitable for bituminous concrete were investigated, and their microstructure compared. Both binders show the formation of asphaltene aggregates. The binder suitable for bituminous concrete is distinguished by the fact that the asphaltenes show a stronger tendency towards such aggregation, due to a higher concentration and less stabilization in the maltene phase. They also show a clear affinity to other species (such as waxes) and may act as nucleation sites for crystals and aggregates of those species. PMID:21118207

  16. Continuous bench-scale slurry catalyst testing direct coal liquefaction rawhide sub-bituminous coal

    Bauman, R.F.; Coless, L.A.; Davis, S.M. [and others


    In 1992, the Department of Energy (DOE) sponsored research to demonstrate a dispersed catalyst system using a combination of molybdenum and iron precursors for direct coal liquefaction. This dispersed catalyst system was successfully demonstrated using Black Thunder sub-bituminous coal at Wilsonville, Alabama by Southern Electric International, Inc. The DOE sponsored research continues at Exxon Research and Development Laboratories (ERDL). A six month continuous bench-scale program using ERDL`s Recycle Coal Liquefaction Unit (RCLU) is planned, three months in 1994 and three months in 1995. The initial conditions in RCLU reflect experience gained from the Wilsonville facility in their Test Run 263. Rawhide sub-bituminous coal which is similar to the Black Thunder coal tested at Wilsonville was used as the feed coal. A slate of five dispersed catalysts for direct coal liquefaction of Rawhide sub-bituminous coal has been tested. Throughout the experiments, the molybdenum addition rate was held constant at 100 wppm while the iron oxide addition rate was varied from 0.25 to 1.0 weight percent (dry coal basis). This report covers the 1994 operations and accomplishments.

  17. JV Task 126 - Mercury Control Technologies for Electric Utilities Burning Bituminous Coal

    Jason Laumb; John Kay; Michael Jones; Brandon Pavlish; Nicholas Lentz; Donald McCollor; Kevin Galbreath


    The EERC developed an applied research consortium project to test cost-effective mercury (Hg) control technologies for utilities burning bituminous coals. The project goal was to test innovative Hg control technologies that have the potential to reduce Hg emissions from bituminous coal-fired power plants by {ge}90% at costs of one-half to three-quarters of current estimates for activated carbon injection (ACI). Hg control technology evaluations were performed using the EERC's combustion test facility (CTF). The CTF was fired on pulverized bituminous coals at 550,000 Btu/hr (580 MJ/hr). The CTF was configured with the following air pollution control devices (APCDs): selective catalytic reduction (SCR) unit, electrostatic precipitator (ESP), and wet flue gas desulfurization system (WFDS). The Hg control technologies investigated as part of this project included ACI (three Norit Americas, Inc., and eleven Envergex sorbents), elemental mercury (Hg{sup 0}) oxidation catalysts (i.e., the noble metals in Hitachi Zosen, Cormetech, and Hitachi SCR catalysts), sorbent enhancement additives (SEAs) (a proprietary EERC additive, trona, and limestone), and blending with a Powder River Basin (PRB) subbituminous coal. These Hg control technologies were evaluated separately, and many were also tested in combination.

  18. Fatigue and healing properties of bituminous mastics reinforced with nano-sized additives

    Santagata, Ezio; Baglieri, Orazio; Tsantilis, Lucia; Dalmazzo, Davide; Chiappinelli, Giuseppe


    The research work described in the paper focused on fatigue and healing properties of bituminous mastics reinforced with nano-sized additives. Commercially available multiwall carbon nanotubes (CNTs) and montmorillonite nanoclay (NC) were combined with a single base bitumen and a standard mineral filler to produce bituminous mastics. These blends were prepared in the laboratory by making use of a technique consisting in simple shear mixing followed by sonication. Fatigue behaviour of mastics under repeated loading was investigated by means of time sweeps performed in the strain-controlled mode at various amplitudes. Healing potential was assessed by adopting a testing protocol specifically conceived to discriminate between recovery of damage induced by fatigue loading and other artefact phenomena which may affect material response. All rheological measurements were carried out with a dynamic shear rheometer in the parallel plates geometry. Outcomes of the experimental investigation were found to be highly dependent on the nature of additive type, as a result of the key role played by interaction mechanisms that nano-particles can establish within the bituminous mastic.

  19. Study on Plastic Coated Overburnt Brick Aggregate as an Alternative Material for Bituminous Road Construction

    Dipankar Sarkar


    Full Text Available There are different places in India where natural stone aggregates are not available for constructional work. Plastic coated OBBA can solve the problem of shortage of stone aggregate to some extent. The engineers are always encouraged to use locally available materials. The present investigation is carried out to evaluate the plastic coated OBBA as an alternative material for bituminous road construction. Shredded waste plastics are mixed with OBBA in different percentages as 0.38, 0.42, 0.46, 0.50, 0.54, and 0.60 of the weight of brick aggregates. Marshall Method of mix design is carried out to find the optimum bitumen content of such bituminous concrete mix prepared by plastic coated OBBA. Bulk density, Marshall Stability, flow, Marshall Quotient, ITS, TSR, stripping, fatigue life, and deformations have been determined accordingly. Marshall Stability value of 0.54 percent of plastic mix is comparatively higher than the other mixes except 0.60 percent of plastic mix. Test results are within the prescribed limit for 0.54 percent of plastic mix. There is a significant reduction in rutting characteristics of the same plastic mix. The fatigue life of the mix is also significantly higher. Thus plastic coated OBBA is found suitable in construction of bituminous concrete road.

  20. Development of new engine bearings with overlay consisting of solid lubricants; Kotai junkatsu overlay tsuki engine yo suberi jikuuke zairyo no kaihatsu

    Kanayama, H.; Kawakami, S.; Gohara, C. [Taiho Kogyo Co. Ltd., Aichi (Japan); Fuwa, Y.; Michioka, H. [Toyota Motor Corp., Aichi (Japan)


    Recently, modern engines have a tendency for higher output and longer periods. As a result , higher bearing performance is required. For this reason, we have developed the new conceptual overlay consisting of solid lubricants and thermosetting plastics. This paper describes the performance of engine bearings with the new overlay. 5 refs., 13 figs., 5 tabs.

  1. Residual stress reduction in the penetration nozzle weld joint by overlay welding

    Highlights: • Residual stress reduction in penetration weld nozzle by overlay welding was studied. • The overlay weld can decrease the residual stress in the weld root. • Long overlay welding is proposed in the actual welding. • Overlay weld to decrease residual stress is more suitable for thin nozzle. - Abstract: Stress corrosion cracking (SCC) in the penetration nozzle weld joint endangers the structural reliability of pressure vessels in nuclear and chemical industries. How to decrease the residual stress is very critical to ensure the structure integrity. In this paper, a new method, which uses overlay welding on the inner surface of nozzle, is proposed to decrease the residual stresses in the penetration joint. Finite element simulation is used to study the change of weld residual stresses before and after overlay welding. It reveals that this method can mainly decrease the residual stress in the weld root. Before overlay welding, large tensile residual stresses are generated in the weld root. After overlay weld, the tensile hoop stress in weld root has been decreased about 45%, and the radial stress has been decreased to compressive stress, which is helpful to decrease the susceptibility to SCC. With the increase of overlay welding length, the residual stress in weld root has been greatly decreased, and thus the long overlay welding is proposed in the actual welding. It also finds that this method is more suitable for thin nozzle rather than thick nozzle

  2. Analysis of an Orthotropic Deck Stiffened with a Cement-Based Overlay

    Walter, Rasmus; Olesen, John Forbes; Stang, Henrik;


    finite-element method. The stiffness of the steel deck reinforced with an overlay depends highly on the composite action. The composite action is closely related to cracking of the overlay and interfacial cracking between the overlay and underlying steel plate (debonding). As an example, a real size...... of crack widths. Furthermore, the analysis shows that debonding is initiated for a certain crack width in the overlay. The load level where cracking and debonding is initiated depends on the stress-crack opening relationship of the material....... can influence the cracking behavior of the cement-based overlay system. Both mechanical and environmental loading have to be considered, and effects such as shrinkage, temperature gradients, and traffic loading are taken into account. The performance of four overlay materials are investigated in terms...

  3. A Popularity-Aware Semantic Overlay for Efficient Peer-to-Peer Search

    LEE, C.


    Full Text Available This paper presents a novel semantic overlay scheme that connects peers based on the similarity of their contents. Semantic closeness among overlay peers can effectively be determined via the exchanges of their content summary using Bloom filters. The overlay link quality is further improved by carefully selecting semantic neighbors according to their potential to contribute to content-based searches. The basic idea behind the semantic neighbor selection is that highly replicated documents should not excessively dominate the overlay topology, overshadowing rare to modestly-replicated items whose query efficiency is often more critical for overall search performance. The efficacy of the proposed semantic overlay is validated through our simulation study which demonstrates superior overlay link quality and query routing performance.

  4. Opportunistic transmitter selection for selfless overlay cognitive radios

    Shaqfeh, Mohammad


    We propose an opportunistic strategy to grant channel access to the primary and secondary transmitters in causal selfless overlay cognitive radios over block-fading channels. The secondary transmitter helps the primary transmitter by relaying the primary messages opportunistically, aided by a buffer to store the primary messages temporarily. The optimal channel-aware transmitter- selection strategy is the solution of the maximization of the average secondary rate under the average primary rate requirement and the buffer stability constraints. Numerical results demonstrate the gains of the proposed opportunistic selection strategy. © 2013 IEEE.

  5. Solidification paths in modified Inconel 625 weld overlay material

    Chandrasekaran, Karthik; Tiedje, Niels Skat; Hald, John


    . Metallographic analysis of solidified samples of Inconel 625 with addition of selected elements is compared with thermodynamic modelling of segregation during solidification. The influence of changes in the melt chemistry on the formation of intermetallic phases during solidification is shown. In particular......, focus is put on how the composition of the dendrite core is affected by modifications to the alloy. It has previously been shown that when the overlay material corrodes, the corrosion take place in the dendrite core. Therefore, the discussion will be directed towards explaining the extent to which the...

  6. A Popularity-Aware Semantic Overlay for Efficient Peer-to-Peer Search

    Lee, C.(Institute of Physics, Academia Sinica, Taipei, Taiwan); Choi, J.; Kim, E.


    This paper presents a novel semantic overlay scheme that connects peers based on the similarity of their contents. Semantic closeness among overlay peers can effectively be determined via the exchanges of their content summary using Bloom filters. The overlay link quality is further improved by carefully selecting semantic neighbors according to their potential to contribute to content-based searches. The basic idea behind the semantic neighbor selection is that highly replica...

  7. 3D Finite Element Analysis of HMA Overlay Mix Design to Control Reflective Cracking

    Ghauch, Ziad G.


    This study examines the effectiveness of HMA overlay design strategies for the purpose of controlling the development of reflective cracking. A parametric study was conducted using a 3D Finite Element (FE) model of a rigid pavement section including Linear Viscoelastic (LVE) material properties for the Hot Mix Asphalt (HMA) overlay and non-uniform tire-pavement contact stresses. Several asphalt mixtures were tested in the surface, intermediate, and leveling course of the HMA overlay. Results ...

  8. Influence of temperature variation on the reflective cracking behaviour of asphalt overlays

    Minhoto, Manuel; Pais, Jorge; Pereira, Paulo


    The objective of this paper is to present a study about the influence of temperature on the reflective cracking behavior through the evaluation of the overlay damage associated to the temperature variation during the year. The development of this study war based on the numerical simulation of the overlay behaviour, based on a three-dimensional finite-element analysis, considering the simultaneous loading of traffic and temperature variation and considering the most predominant type of overlay...

  9. Effect of PCC Joint Skew on Reflective Cracking in HMA Overlays

    Ghauch, Ziad G.


    Reflective cracking is a relatively premature distress that occurs in HMA materials overlaying cracked and jointed underlying pavements. The high concentration of stresses and strains in the vicinity of the discontinuity of the old pavement causes the cracks to reflect into the newly placed HMA overlay. While it is a common practice to use skewed transverse joints in rigid pavements to improve the latter's performance, the impact of such a practice on the cracking of a potential HMA overlay h...

  10. Questioning the benefits that coloured overlays can have for reading in students with and without dyslexia

    Henderson, Lisa-Marie; Tsogka, Natassa; Snowling, Maggie


    Visual stress (the experience of visual distortions and discomfort during prolonged reading) is frequently identified and alleviated with coloured overlays or lenses. Previous studies have associated visual stress with dyslexia and as a consequence, coloured overlays are widely distributed to children and adults with reading difficulty. However, this practice remains controversial. We investigated whether overlays have advantageous and reliable benefits for reading in undergraduate students w...

  11. Lightweight storage and overlay networks for fault tolerance.

    Oldfield, Ron A.


    The next generation of capability-class, massively parallel processing (MPP) systems is expected to have hundreds of thousands to millions of processors, In such environments, it is critical to have fault-tolerance mechanisms, including checkpoint/restart, that scale with the size of applications and the percentage of the system on which the applications execute. For application-driven, periodic checkpoint operations, the state-of-the-art does not provide a scalable solution. For example, on today's massive-scale systems that execute applications which consume most of the memory of the employed compute nodes, checkpoint operations generate I/O that consumes nearly 80% of the total I/O usage. Motivated by this observation, this project aims to improve I/O performance for application-directed checkpoints through the use of lightweight storage architectures and overlay networks. Lightweight storage provide direct access to underlying storage devices. Overlay networks provide caching and processing capabilities in the compute-node fabric. The combination has potential to signifcantly reduce I/O overhead for large-scale applications. This report describes our combined efforts to model and understand overheads for application-directed checkpoints, as well as implementation and performance analysis of a checkpoint service that uses available compute nodes as a network cache for checkpoint operations.

  12. Time dependent viscoelastic rheological response of pure, modified and synthetic bituminous binders

    Airey, G. D.; Grenfell, J. R. A.; Apeagyei, A.; Subhy, A.; Lo Presti, D.


    Bitumen is a viscoelastic material that exhibits both elastic and viscous components of response and displays both a temperature and time dependent relationship between applied stresses and resultant strains. In addition, as bitumen is responsible for the viscoelastic behaviour of all bituminous materials, it plays a dominant role in defining many of the aspects of asphalt road performance, such as strength and stiffness, permanent deformation and cracking. Although conventional bituminous materials perform satisfactorily in most highway pavement applications, there are situations that require the modification of the binder to enhance the properties of existing asphalt material. The best known form of modification is by means of polymer modification, traditionally used to improve the temperature and time susceptibility of bitumen. Tyre rubber modification is another form using recycled crumb tyre rubber to alter the properties of conventional bitumen. In addition, alternative binders (synthetic polymeric binders as well as renewable, environmental-friendly bio-binders) have entered the bitumen market over the last few years due to concerns over the continued availability of bitumen from current crudes and refinery processes. This paper provides a detailed rheological assessment, under both temperature and time regimes, of a range of conventional, modified and alternative binders in terms of the materials dynamic (oscillatory) viscoelastic response. The rheological results show the improved viscoelastic properties of polymer- and rubber-modified binders in terms of increased complex shear modulus and elastic response, particularly at high temperatures and low frequencies. The synthetic binders were found to demonstrate complex rheological behaviour relative to that seen for conventional bituminous binders.

  13. The projects of reducing environmental pollution at the collieries belonging to Petrosani Autonomous Bituminous Coal Administration

    The economic development in the Jiu Valley, as practised in the mining and processing of bituminous coal, has had a dynamic character without taking into account, however, the harmful impact on the environment. The most severe problem of environmental pollution in the Jiu Valley is that of the pollution of the Jiu River due to the discharge of waste water from the technological processes of mining and processing coal. This paper presents some solutions for reducing this environmental pollution, especially the Jiu water pollution. 1 ref

  14. Fire and explosion incident at bituminization demonstration facility of PNC Tokai works, on march 11, 1997

    On March 11, a fire and explosion incident occurred at the Bituminization Demonstration Facility (BDF) of Tokai Reprocessing Plant in Power Reactor and Nuclear Fuel Development Corporation (PNC). Soon after the incident, PNC (now reorganized to JNC) started to investigate the facility damage, operational records around the incident, technical notes including facility design and reviews of R and D results, operators witness and to perform several analysis, tests and calculations. This paper describes outline and cause of the incident which were concluded based on the results of continuous serious investigation, analysis and calculation. (author)

  15. Investigation of activity release from bituminized intermediate-level waste forms under thermal stresses

    To determine the consequences of a fire during fabrication, intermediate storage and transport of bituminized NaNO3 waste forms, the fractions of plutonium released from the waste forms were assessed. For this purpose, laboratory tests were made with PuO2-containing specimens as well as a field test with specimens containing Eu2O3. By the evaluation of plutonium release in the laboratory and by the determination of the total sodium release and the relative Eu/Na release in the field tests the plutonium release can be deduced from full-scale specimens. The results show that for bituminized waste forms with high NaNO3 contents (approx. 36 wt%) the average plutonium release obtained in laboratory testing is 15%. In the field tests (IAEA fire test conditions) an average Eu release of 8% was found. These results justify the statement that also for waste forms in open 175 L drum inserts a maximum plutonium release of about 15% can be expected. From the time-dependence of Eu/Na release in the field tests an induction period of 15-20 minutes between the start of testing and the first Na/Eu release can be derived. The maximum differential Na/Eu release occurs after a test period of 45 to 60 minutes duration and after 90 to 105 minutes (tests K2 and K4, respectively); after that time also the highest temperatures in the products are measured. The release values were determined for products in open 175 L drum inserts which in this form are not eligible for intermediate and ultimate storage. For bituminized waste forms in concrete packages (lost concrete shieldings) a delayed increase in temperature to only 70-80 deg. C takes place (4-5 hours after extinction of the fire) if the fire lasts 45 minutes. The concrete package remains intact under test conditions. This means that activity release from bituminized waste forms packaged in this way can be ruled out in the case under consideration. (author)

  16. Bituminization of radioactive waste concentrates from reprocessing, nuclear research establishments and nuclear power plants

    This report is a summary of the major results of R and D work performed at the Karlsruhe Nuclear Research Center from 1967 until 1977 for fixing radioactive waste concentrates in bitumen and for characterizing the resulting products. Moreover, the report provides a compilation of operating experience gathered at the Karlsruhe Nuclear Research Center in bituminizing low and medium level evaporator concentrates. The report also contains the results of R and D work carried out by external institutes on behalf of the KfK. (orig.)

  17. A Method to Estimate the Dynamic Displacement and Stress of a Multi-layered Pavement with Bituminous or Concrete Materials

    Zheng LU


    Full Text Available In this research work, a method to estimate the dynamic characteristics of a multilayered pavement with bituminous or concrete materials is proposed. A mechanical model is established to investigate the dynamic displacement and stress of the multi-layered pavement structure. Both the flexible and the rigid pavements, corresponding to bituminous materials and concrete materials, respectively, are studied. The theoretical solutions of the multi-layered pavement structure are deduced considering the compatibility condition at the interface of the structural layers. By introducing FFT (Fast Fourier Transform algorithm, some numerical results are presented. Comparisons of the theoretical and experimental result implied that the proposed method is reasonable in predicting the stress and displacement of a multi-layered pavement with bituminous or concrete materials. DOI:

  18. Questioning the Benefits That Coloured Overlays Can Have for Reading in Students with and without Dyslexia

    Henderson, Lisa M.; Tsogka, Natassa; Snowling, Margaret J.


    Visual stress (the experience of visual distortions and discomfort during prolonged reading) is frequently identified and alleviated with coloured overlays or lenses. Previous studies have associated visual stress with dyslexia and as a consequence, coloured overlays are widely distributed to children and adults with reading difficulty. However,…

  19. Toward 7nm target on product overlay for C028 FDSOI technology

    Gatefait, Maxime; Le-Gratiet, Bertrand; Goirand, Pierre Jerome; Lam, Auguste; Van Haren, Richard; Pastol, Anne; Doytcheva, Maya; Liu, Xing Lan; Beltman, Jan


    The continuous need for lithography overlay performance improvement is a key point for advanced integrated circuit manufacturing. Overlay control is more and more challenging in the 2x nm process nodes regarding functionality margin of the chip and tool capability. Transistor architecture rules which are set, confirm poly to contact space as the most critical one for 28nm technology node. Critical Dimension variability of these layers, even with best in class process stability, in addition to design constraint lead to on product overlay specifications of around 7nm. In order to ensure that the target is met in production environment and to identify potential ways for improvement, identification of the contributors to overlay errors is essential. We have introduced a novel budget breakdown methodology using both bottom-up and top-down overlay data. For the bottom up part, we have performed extensive testing with very high sampling scheme so as to quantify the main effects. In-line overlay metrology data has been used for top down approach to verify the overall performance in production. In this paper we focused on the 28nm contact to gate overlay in a FDSOI process. The initial inconsistency between bottom up and top down results led us to further exploration of the root cause of these inconsistencies. We have been able to highlight key figures to focus on, like reticle heating, wafer table contamination and etch processing effects. Finally, we conclude on 7nm overlay target achievement feasibility in high volume manufacturing environment.

  20. Low SO2 emission from CFB co-firing MSW and bituminous.

    Lu, Qing-Gang; Li, Zhi-Wei; Na, Yong-Jie; Ba, Shao-Lin; Sun, Yun-Kai; He, Jun


    Influence of co-firing rate on SO2 emission from co-firing municipal solid waste (MSW) and bituminous containing high amount of sulfur (1.79%) was studied in a 0.15 MWt circulating fluidized bed (CFB). The temperature selected is 1123 K, typical for MSW incineration using CFB. The particle concentration in the dilution zone of the furnace, the alkali metal concentration and sulfate concentration in the recirculating ash and fly ash, and flue gas composition were determined. The results showed that the addition of MSW leads to a significant decrease in SO2 emission. Concentration of SO2 in flue gas decreased to 0 with the co-firing rate greater than 51%. This reduction in SO2 emission is attributed both to the high particle concentration in the dilution zone of the furnace, the high content of alkali metals in the bed material, and to the comparatively high concentration of HCI in flue gas during co-firing of MSW and bituminous. PMID:15559820


    Berislav Šebečić


    Full Text Available It is assumed thal the first known sedimens of natural bitumen or asphalt in coastal Croatia were exploited as the early moddle ages. Yet authenticated written documents about Vinišće near Trogir derive from no earlier than 1628, about Vrgorac/Paklina from only 1753. By the end of the 18th century, many deposits were discovered in Dalmatia, but it was Škrip on the Island of Brač and Suhi Dolac that were important. The earliest known deposits and occurrences of kerogenous rocks, or bituminous or oil shales, are mentioned as stone or fossil coal in Sovinjak, in the upper course of the River Mirna, and in Rebići in Istria; near Sinj, Slivno not far from the River Neretva, Mirta and near Nerežišće on the Island uf Brač. All if these were well known and described in 1804, while Sovinjak was mentioned in the 16th century. In the article, some of new information derived from mining and geological research into bituminous and kerogenous sediments and deposits are provided (the paper is published in Croatian.

  2. Assessing radioactive concentrates and waste vapor condensate in solidifying radioactive wastes by bituminization

    A brief overview is presented of chemical and radiochemical methods used in the world for the analysis of the concentrate of liquid radioactive wastes from nuclear power plants destined for bituminization. Most methods are also suitable for an analysis of the condensate of waste vapors produced in bituminization. The methods of analysis of the radioactive concentrate from the V-1 nuclear power plant in Jaslovske Bohunice and of the waste vapors condensate were developed and tested in practice. Gross gamma activity was measured using a well-type Na(Tl) scintillation detector, the content of radionuclides was determined using semiconductor Ge(Li) spectrometry. The concentration of boric acid in the concentrate was determined by titration with mannite; in the condensate, using spectrophotometry with curcumine. The content of nitrates in both the concentrate and the condensate was determined spectrophotometrically using salicylic acid, the content of nitrites was determined by spectrophotometry using sulfanilic acid and α-naphthylamine. Carbonates and chlorides were determined by titration, sodium and potassium by flame photometry. The content of organic acids was measured by gravimetry of extracted methyl esters, the content of surfactants by spectrophotometry. Infrared spectrophotometry was used in determining hydrocarbons in the waste vapor condensate. The measured value range and the measurement errors are shown for each method. (A.K.)

  3. Feasibility study of producing lump fuel using oil-bituminous sands

    Moldybaev, A.B.; Ermagambetov, B.T.; Mamraeva, K.M.; Shin, R.G.; Bakirova, R.K. (Institut Organicheskogo Sinteza i Uglekhimii AN KazSSR (USSR))


    Describes production of lump fuel by briquetting and coking different mixtures of non-caking coal with coal preparation sludge and bitumen extracted from oil sands. The coal used was from the Shubarkol'sk coal deposit (USSR); the sludge was from the Saburkhanskaya preparation plant. Properties and composition of oil-bituminous sands and of bitumen to be used as binder are given. Technological details of the briquetting and coking processes are provided. Results show that briquets produced from mixtures of coal and oil-bituminous sands can only be used as a high-ash lump fuel, which cannot be further processed into semicoke. Experiments were carried out briquetting coal or coke, sludge and 6-8% bitumen extracted from the sands, varying coal or coke grain fractions and composition of the mixture. An increased briquet strength was found after using the vacuum-distilled 300-350 C bitumen fraction. Briquets from this non-caking coal with bitumen binder are regarded as ecologically clean fuel. 5 refs.

  4. Overlay cognitive radio systems with adaptive two-way relaying

    Hyadi, Amal


    In this paper, we propose a spectrum sharing mechanism with a two-phase two-way relaying protocol for an overlay cognitive network. The system comprises two primary users (PUs) and two secondary users (SUs). One of the SUs acts as a relay for the PUs and gains spectrum sharing as long as he respects outage probability constraints of the primary system. Moreover, we consider that the relaying node performs an optimal power allocation scheme that minimizes the outage performance of the secondary receiver. Closed form expressions for the outage probability are derived for the cases of Decode-and-Forward (DF), Amplify-and-Forward (AF), and adaptive relaying. Numerical simulations are presented to illustrate and compare the obtained results. © 2013 IEEE.

  5. Range of slow positrons in metal overlayers on Al

    Nielsen, B.; Lynn, K.G.; Leung, T.C. (Brookhaven National Laboratory, Upton, New York 11973 (USA)); Van der Kolk, G.J.; Van Ijzendoorn, L.J. (Philips Research Laboratories, 5600 JA Eindhoven, (Netherlands))


    Polycrystalline Pd and amorphous PdTa films on Al substrates were studied by a variable energy positron beam and by Rutherford backscattering. Since positron diffusion in the overlayers is limited, the range follows directly from the Doppler broadening as a function of incident positron energy. To observe possible effects of positron backscattering, a sandwich of Al/Pd/Al was studied as well. It was found that the mean penetration depth is not described well by {bar {ital z}}({ital E})={ital A}({mu}g/cm{sup 2}){times}{ital E}{sup {ital n}({ital E})}, if {ital A} and {ital n} are assumed to be material and energy independent.

  6. Utilization of Waste Clay from Boron Production in Bituminous Geosynthetic Barrier (GBR-B) Production as Landfill Liner

    Müfide Banar; Yücel Güney; Aysun Özkan; Zerrin Günkaya; Eren Bayrakcı; Derya Ulutaş


    Bituminous geomembranes, one type of geosynthetics, include a hot bituminous mixture with mineral filler and reinforcement. In this study, boron production waste clay (CW) was used as filler to produce a geosynthetic barrier with bentonite, waste tire, and bitumen. Bentonite and waste tires were used as auxiliary fillers and bitumen as the binder. CW/bitumen, CW/bentonite/bitumen, and CW/waste tire/bitumen mixtures were prepared by using a laboratory mixer at 100°C. Hot mixtures were extruded...

  7. Exact and reliable overlay metrology in nanoscale semiconductor devices using an image processing method

    Park, Jinkook; Shin, ChaeHo; Kim, Minkook; Kim, Junghwan; Park, JeongKyun; Kim, JungSoo; Jun, ChungSam; Yim, Yeny; Lee, Janghee


    As semiconductor processing becomes more complicated and pattern sizes shrink, the overlay metrology has become one of the most important issues in the semiconductor industry. Therefore, in order to obtain correct, reliable overlay values in semiconductor fabrication facilities (fab), quantization methods for the efficient management and implementation of a measurement algorithm are required, as well as an understanding of the target structures in the semiconductor device. We implemented correct, reliable overlay values in the pattern using the image processing method. The quantization method, through correlation analysis and a new algorithm for target structures, were able to improve the sensitivity to misalignment in the pattern and enable more stable and credible in-line measurement by decreasing the distribution of the residuals in overlay values. Since overlay values of the pattern in the fab were measured and managed more reliably and quickly, it is expected that our study will be able to contribute to the yield enhancement of semiconductor companies.

  8. Measurement of thickness of austenitic overlays on carbon steel walls using a magnetic method

    Mechanical and magnetic methods are used for measuring the thickness of austenitic overlays on the walls of carbon steel pressure vessels. Specific problems pertaining to the magnetic methods are briefly discussed. A magnetic thickness gage has been developed for overlays using the principle of ferrite effect suppression. Thickness gaging is done by aligning the gage with the layer to be measured on the overlay side. Basic accuracy of the instrument is 7% for overlays containing 2 to 8% ferrite. For the ferrite content 0 to 2% or 8 to 10%, accuracy reduces to roughly 12%. The method is simple, reliable and versatile during the manufacture of a pressure vessel and after it is finished. The economic benefit is considerable because it allows overlaying of a thickness which practically is without reserve; each millimeter of the austenitic layer thickness on the pressure vessel costs more than a million Czechoslovak crowns. (Z.M.). 7 figs., 5 refs

  9. Strain Response of Hot-Mix Asphalt Overlays for Bottom-Up Reflective Cracking

    Ghauch, Ziad G


    This paper examines the strain response of typical HMA overlays above jointed PCC slabs prone to bottom-up reflective cracking. The occurrence of reflective cracking under the combined effect of traffic and environmental loading significantly reduces the design life of the HMA overlays and can lead to its premature failure. In this context, viscoelastic material properties combined with cyclic vehicle loadings and pavement temperature distribution were implemented in a series of FE models in order to study the evolution of horizontal tensile and shear strains at the bottom of the HMA overlay. The effect of several design parameters, such as subbase and subgrade moduli, vehicle speed, overlay thickness, and temperature condition, on the horizontal and shear strain response was investigated. Results obtained show that the rate of horizontal and shear strain increase at the bottom of the HMA overlay drop with higher vehicle speed, higher subgrade modulus, and higher subbase modulus. Moreover, the rate of horizon...

  10. Effect of PCC Joint Skew on Reflective Cracking in HMA Overlays

    Ghauch, By Ziad G


    Reflective cracking is a relatively premature distress that occurs in HMA materials overlaying cracked and jointed underlying pavements. The high concentration of stresses and strains in the vicinity of the discontinuity of the old pavement causes the cracks to reflect into the newly placed HMA overlay. While it is a common practice to use skewed transverse joints in rigid pavements to improve the latter's performance, the impact of such a practice on the cracking of a potential HMA overlay has not been examined so far. In this context, this study investigates the effect of using skewed transverse joints in rigid pavements on reflective cracking development in the HMA overlay. Advanced three-dimensional Finite Element models including viscoelastic material properties for the HMA overlay, 3D beam modeling of dowel bars, non-uniform tire-pavement contact stresses, friction interfaces, and infinite boundary elements were constructed for both normal and skewed transverse joints using ABAQUS v-6.11. The potential ...

  11. Overlaying alloys for sealing surfaces of valves for primary circuits in nuclear power plants

    The requirements are presented for cobalt-free overlaying alloys such as hardness, a low friction coefficient, resistance to rapid temperature changes, structural stability. Alloy E-C-1111 was tested for the said requirements. Its composition is C max. 0.11%, Mn 4.3-4.5%, Si 4.2-5.3%, Cr 17.0-19.0%, Ni 7.5-9.0%, Mo 5.0-5.8%, and Nb 0.9-1.2%. It was found to show acceptable technological and mechanical properties for operation. Overlaying up to an inner diameter of 40 mm can be done without pre-heating, large semi-products should be preheated to 500 to 550 degC. After overlaying to a certain height, heat treatment and capillary testing are necessary to check that the overlay does not show cracks. It is recommended that small inner diameter parts should be overlayed layer by ayer. (J.P.)

  12. Study of thin organic overlayers by local probe microscopies

    In Scanning Tunneling Microscopy (STM) and Atomic Force Microscopy (AFM), the interaction of a very sharp tip with a surface is used to gather information on the latter. In STM, the interaction is measured as an electric current, and in AFM as a force acting on the tip. AFM, which does not require the sample to be electrically conducting, is more general than STM which does, so the study of organic overlayers by STM is limited to very thin layers (thickness comparable to a tunnelling distance i.e. 10 A), onto conducting substrates. On the other hand, spatial resolution to the atomic scale can hardly be obtained in AFM, and the corresponding mechanism is poorly understood. In all cases, the information obtained is mainly topographic, i.e. crystallographic (at the atomic scale) or morphological (at larger scales). Several examples will be discussed. Monomolecular layers on conducting substrates in air, under vacuum, or in contact with the corresponding bulk liquid, have been studied by STM. Two-dimensional periodic structures, not found in the bulk crystals, are observed, as well as different kinds of point or line defects. This emphasizes the importance of molecule-substrate interactions in competition with the usual intermolecular interactions. There are few STM studies of thin continuous polymeric overlayers. Early studies of biological macromolecules have been frustrated by artefacts due to substrate surface defects which mimic the expected polymer images, so AFM is now preferred, at the expense of resolution. AFM is now intensively used for studying the surface morphology of thicker (more than one molecule thick) films of organic molecules or polymers. However, the force exerted by the tip on the surface is often large enough to modify organic surfaces; a more recent variant of AFM, the so-called ''tapping mode'', in which that interaction is reduced, will be presented. A few examples of polymer surface studies using AFM will be discussed

  13. Mechanical properties of hot bituminous mixes manufactured with recycled aggregate of Silestone® waste

    Rubio, M. C.


    Full Text Available This article presents the results of a research project which analyzes the viability of incorporating waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes. For this purpose, various bituminous mixes were manufactured with waste aggregate in different percentage. A set of tests were carried out that permitted the characterization of the mechanical behavior of these mixes. The results of these tests were similar to the results obtained when conventional mixes made from virgin quarry aggregate were tested. The results for moisture sensitivity as well as for wheel track rutting on mixes showed the optimal performance of this waste material even under very demanding traffic conditions. Laboratory studies showed that the use of this waste material in the manufacture of bituminous mixes is technically viable and can provide high-quality recycled aggregates at a very low cost, which can be used in the pavement of road.

    Este artículo muestra los resultados de un proyecto de investigación que tiene por objeto analizar la viabilidad de incorporación de residuos procedentes de piedra decorativa en la fabricación de mezclas bituminosas en caliente. Para ello se fabricaron mezclas con áridos reciclados de residuos procedentes de piedra decorativa en distintos porcentajes, realizando un conjunto de ensayos que posibilitaron caracterizar el comportamiento mecánico de dichas mezclas. Los resultados obtenidos fueron similares a los de las mezclas convencionales fabricadas con áridos vírgenes procedentes de cantera. Los valores de resistencia conservada ante la acción del agua y deformación en pista, pusieron de manifiesto la aptitud del residuo incluso ante las condiciones de tráfico más exigentes. Los trabajos realizados en el laboratorio indican que la utilización del residuo en la fabricación de mezclas bituminosas es técnicamente viable, pudiendo obtenerse áridos reciclados de gran calidad y

  14. Development prospects for Bazhenov formation bituminous claystones in the southeast of the West Siberian Plate (Tomsk Region)

    The article considers the use of time-tested bituminous shale development technologies in the southeast of the West Siberian Plate (Tomsk Region). A research target is the bituminous claystones of the Bazhenov formation. The Bazhenov formation was divided into stratigraphic units, and the sequence of forming these units within the territory under study was restored on the basis of the peculiarities of the Bazhenov formation section structure with gamma-ray logging data. The joint analysis of logs (gamma-ray logging, resistivity logging, SP logging, neutron gamma-ray logging, induction logging) and core data revealed the wide development of carbonatization processes in the lower stratigraphic units of the Bazhenov formation, whereas the upper, most bituminous units do not have the signs of carbonatization. It is a favorable factor for using the existing technologies of producing hydrocarbons from analogous sedimentary deposits. Considering the degree of lithological disconnection of an oilbearing object from adjacent reservoir formations allows making a conclusion that the application of the existing technologies for developing bituminous claystones can be implemented only in the insignificant territory of the area under study where the Bazhenov formation overlies Georgiev formation claystones being over 8 meters thick. To develop the oil and gas potential of the Bazhenov formation in other territories, there will be a need for new technologies that allow forming a fracture-cavernous matrix in a carbonate rock

  15. Corrosion resistance and microstructure of alloy 625 weld overlay on ASTM A516 grade 70

    Nickel-based alloys are a crucial class of materials because of their excellent corrosion resistance. In the present study, single layer and two layers alloy 625 weld overlays were deposited by GTAW process on A516 grade 70 carbon steel. The dilution in terms of Fe, Ni, Mo and Nb content was calculated in 30 points of weld overlay. Microstructure observations showed that alloy 625 had austenitic structure with two types of Laves and NbC secondary phases. The uniform and pitting corrosion resistance of alloy 625 weld overlay as casted and as forged were evaluated in accordance with ASTM G48-2011 standard at different temperatures to determine the weight loss and critical pitting temperature. For achieving a better comparison, samples from alloy 625 as casted and as forged were tested under the same conditions. The results point out that single layer alloy 625 weld overlay is not suitable for chloride containing environments, two layers alloy 625 weld overlay and alloy 625 as casted have acceptable corrosion resistance and almost the same critical pitting temperature. Alloy 625 as forged has the best corrosion resistance and the highest critical pitting temperature among all test specimens. Also, the corrosion behavior was evaluated in accordance with ASTM G28 standard. The corrosion rate of single layer weld overlay was unacceptable. The average corrosion rate of two layers weld overlay and in casted condition were 35.82 and 33.01 mpy, respectively.

  16. Examination and comparision of structure: lignite, bituminous and anthracite coal. [10 references

    Winans, R.E.; Hayatsu, R.; Scott, R.G.; Moore, L.P.; Studier, M.H.


    Coal can be described as an amorphous mixture of macromolecules each made up of a complex array of organic molecules chemically linked together. Methods for breaking up these macromolecules in order to characterize the aromatic structural types have been explored. Pyrolysis is a common method for depolymerizing coal, but under the conditions necessary for pyrolysis much structural rearrangement occurs making a comparison of the products to the initial structural groups in coal difficult if not impossible. One approach has been to use a variety of selective oxidation methods. Aqueous sodium dichromate, aqueous air oxidation with uv light, and hydrogen peroxide in acetic acid have been used. Initial results of some of these studies have been published. This work has been extended to include characterization and comparison of a lignite, bituminous coal, and anthracite. Besides the oxidation products, the monomeric organic molecules trapped within the macromolecules are examined and the results interpreted in relation to coal structure and the coalification process.

  17. Bituminization of simulated waste, spent resins, evaporator concentrates and animal ashes by extrusion process

    The results of the study of bituminization of simulated radwaste - spennt ion-exchange resins, borate evaporator/concentrates and animal ashes, are presented and discussed. Distilled and oxidizer bitumen were used. Characterization of the crude material and simulated wastes-bitumen mixtures of varying weigt composition (30, 40, 50, 60% by weight of dry waste material) was carried out. The asphaltene and parafin contents in the bitumens were also determined. Some additives and were used with an aim to improve the characteristcs of solidified wastes. For leaching studies, granular ion-exchange resins were with Cs - 134 and mixtures of resin-bitumen were prepared. The leaching studies were executed using the IAEA recommendation and the ISO method. A conventional screw-extruder, common in plastic industry, was used determine operational parameters and process difficulties. Mixtures of resin-bitumen and evaporator concentrate-bitumen obtained from differents operational conditions were characterized. (Author)

  18. Physical properties of solid fuel briquettes from bituminous coal waste and biomass



    Biomass and bituminous coal fines from four different coalfields were used to produce fuel briquettes.Two physical properties of briquettes,water resistance index and compressive strength were analyzed.The influence of type and quantity of biomass on physical properties was also studied.The results reveal that depending on the mineral content of the coal,the physical properties of the briquettes differ noticeably.The comparison of briquettes with and without biomass showed that the presence of the beet pulp increased CS in all types of coal samples.Samples containing beet pulp had better physical properties than sawdust.Mezino Ⅱ coal briquettes had highest CS and WRI than the other ones.Calorific value of biomass/Mezino Ⅱ coal briquettes was lessened in comparison with raw coal,but it remained in an acceptable range.

  19. Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

    Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu


    A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention. PMID:27136608

  20. Application of laser microprobe (LAMMA 1000) to "fingerprinting" of coal constituents in bituminous coal

    Lyons, P.C.; Hercules, D.M.; Morelli, J.J.; Sellers, G.A.; Mattern, D.; Thompson-Rizer, C. L.; Brown, F.W.; Millay, M.A.


    A laser microprobe (LAMMA-1000) microchemical analysis of vitrinites of different morphologies but similar reflectances within the same bituminous coal bed indicates distinct "fingerprint" spectra. The banded form of vitrinite contains Li, Ti, Ba, Sr, F, and Cl which were not detected in the nonbanded vitrinite. These differences may indicate a different plant source or the introduction of these elements from fluids mobilized during diagenesis. The nonbanded vitrinite (called corpocollinite), which was contained in a pyrite coal-ball seed fern permineralization of Myeloxylon, may have been protected from influx of these elements due to entrapment by pyrite during an early peat stage. An ion at M/Z 65, which is characteristic of the banded vitrinite, may indicate C5H5+ and, perhaps a difference in the chemical structure of the two vitrinites. These results demonstrate that "fingerprint" spectra can be obtained from vitrinite macerals by LAMMA and that these "fingerprints" have genetic implications. ?? 1987.

  1. Progress in developing a model for interaction of bituminized waste products with water

    The reported work is part of a study of long-term properties of bituminized waste products. The long-term goal is: - estimating the swelling and degradation of an agglomerate of ion exchange resins and bitumen when submerged in water, - estimating the consequent pressure build-up and degradation of surrounding barriers in the repository. The report describes the first steps in calculating diffusion of water into the heterogeneous medium of ion exchange resins and bitumen and the consequent swelling of the material. Different models for the effective diffusivity are applied and implemented into a new version of the code GEOPATH which then also considers the swelling due to water uptake. Two-dimensional cylindrical geometry is considered. Results from some test calculations are shown. It is concluded that swelling is an important effect which can be handled theoretically if basic data are available. (authors)

  2. Comparative study of test methods for bituminized and other low- and medium-level solidified waste materials

    Various aspects of the behaviour of bituminized or cemented simulated low- or medium-level radioactive waste in contact with water or salt solutions have been investigated. The solubility (approximately 0.5%) and the diffusion coefficient (approximately 5.10-8 cm2/sec) determining transort of water in pure bitumen have been measured for Mexphalte 40/50 at room temperature. A weighing method has been used to study water uptake and swelling of bituminized sodium nitrate, sodium sulphate or cation-exchange resin. The swelling of samples in contact with water was in some cases very pronounced. In strong salt solutions the tendency to swell is much less. The particle size of the embedded waste material is an important parameter. Thermal pre-treatment of cation-exchange resin before bituminization does not seem to improve the quality of the final product. The interaction between bituminized-exchange resin and concrete barrier materials has been studied. Microbial degradation of bitumen and bituminized waste under aerobic conditions has been investigated. It is probably of minor importance as far as leaching is concerned. A method for measuring leaching from a plane surface of cemented waste has been developed. The method avoids the problem of cracks between the sample and the container. Leaching from cemented sodium nitrate or sulphate was investigated. Absorption of CO2 from the atmosphere was found to have only minor effect on Cs- and Na-leaching but gave a pronounced decrease in Ca-leaching. The use of silica-fume as an additive to cemented sodium nitrate decreased the leach rate by a factor 4. (author)

  3. Uraniferous lignites and bituminous clays of the Serres Basin. Pt. A

    The lignites of the southern area (Christos-Vissiani-Lefkes-Perdikari) and the bituminous clay silts of the northern area (Maramena, Ano Metohi, Chrysopigi) are the main uraniferous beds in the Serres Basin. The sediments of the basin (Upper Miocene to recent) have been stratigraphically divided into three informal unities: the Lefkon, Georgios and Spilia formations. The uraniferous lignites pertaining to the Lefkon limnic-fluvial formation are developed into two discrete horizons, the upper Double Seam and the lower Main Seam. The bituminous clays are of the same age with the lignites, those of Maramena being, however, younger, equivalent to the marine and brackish Georgios formation. The continuity, thickness and dip of the strata reveal considerable regional changes resulting from the intense tectonism of the basin. Further to the surface works the upper lignites have been reached through small excavations and also about 100 boreholes totalling 10,000 m have been drilled. The composition of the organic constituents and the calorific value show a dull transitional to shiny hard lignite with ash rich in pyrite and sulphur. There have been no discrete U minerals detected, while the electron microprobe analysis showed that the uranium is uniformly disseminated into the lignite mass, mainly absorbed through its humic acids. More than 75% of the uranium is extractable, the control of its combustion conditions being, however, a major problem. The potential reserves have been up to date estimated to be of over 4,000 tons (uranium metal), this figure resulting mainly from data evaluated from the borehole γ-ray logs using the computer programmes LOGFILE and LOGPLOT developed at the Radioactive Raw Materials Dept. of the Greek AEC. (author)

  4. Kinetics and equilibrium modeling of uranium(VI) sorption by bituminous shale from aqueous solution

    Highlights: • Oil shales are sedimentary rocks containing a polymeric matter in a mineral matrix. • Sorption potential of bituminous shale (BS) for uranium recovery was investigated. • U(VI) sorption increased with decreasing pH and increasing temperature. • Kinetic data were analyzed based on single and two resistance diffusion models. • The results fit well to the McKay equation assuming film and intraparticle diffusion. - Abstract: Sorption of U(VI) onto a bituminous shale (BS) from a nuclear power plant project site in Black Sea region was investigated for potential risk assessment when it releases into the environment with contaminated ground and surface water. The sorption characteristics of the BS for U(VI) recovery were evaluated as a function of contact time, adsorbent dosage, initial concentration, pH and temperature. Kinetic results fit better with pseudo-second-order model rather than pseudo-first-order. The possibility of diffusion process was analyzed based on Weber–Morris intra-particle diffusion model. The McKay equation assuming film- and intraparticle diffusion better predicted the data than the Vermeulen approximation presuming surface diffusion. Equilibrium sorption data were modeled according to the Langmuir, Dubinin–Radushkevich (D–R) and Freundlich isotherm equations. Sorption capacity increased from 0.10 to 0.15 mmol g−1 in 298–318 K temperature range. FT-IR analysis and pH dependent sorption studies conducted in hydroxide and carbonate media revealed that U(VI) species were sorbed in uranyl and its hydroxo forms on the BS. Desorption studies showed that U(VI) leaching with Black Sea water was negligible from the loaded BS. The activation parameters (Ea, ΔH∗ and ΔG∗) estimated from diffusion coefficients indicated the presence of an energy barrier in the sorption system. However, thermodynamic functions derived from sorption equilibrium constants showed that overall sorption process was spontaneous in nature and

  5. Distribution of inorganic and organic substances in the hydrocyclone separated Slovak sub-bituminous coal

    Anton Zubrik; Slavomir Hredzak; Ludmila Turcaniova; Michal Lovas; Ingo Bergmann; Klaus Dieter Becker; Maria Lukcova; Vladimir Sepelak [Slovak Academy of Sciences, Kosice (Slovakia). Institute of Geotechnics


    A low-rank Slovak sub-bituminous coal from the Handlova deposit was physically treated by washing in a water-only cyclone with the goal to find the separation effect for inorganic (mainly Fe-bearing minerals) and organic substances (humic acids, diterpanes). A high-quality coal product with the ash content in the dry matter of 9.02% and carbon content of C{sup d} = 68.12% at a mass yield of 29.51% was obtained using the water-only cyclone processing. At first, the physically treated coal samples were detailed characterized by XRD, {sup 57}Fe Moessbauer spectroscopy, FT-IR and HR-TEM. In addition to non-crystalline organic coal components, inorganic compounds belonging to silicate minerals (kaolinite, muscovite and quartz) as well as to Fe-bearing sulphide minerals (pyrite) were identified in the sub-bituminous coal by XRD. {sup 57}Fe Moessbauer spectroscopy detected the presence of iron carbonate (siderite), iron-containing clay mineral and two sulphur-containing minerals (pyrite, jarosite) in the untreated coal. On the other hand, only one Fe-bearing mineral, (pyrite) was found in the washed coal. Effect of the physical separation is also demonstrated in FT-IR spectra, where the peak at 1040 cm{sup -1} representing the silicate component in the untreated sample is not detectable in the washed coal sample. Presence of extractive organic substances, i.e. humic acids and tetracyclic diterpane (16a(H)-phyllocladane), in the hydrocyclone products is also evidenced. It was confirmed that the isolated diterpenoic compound is attendant in the washed product with the lowest ash content and it is assimilated with the organic part of coal. Surprisingly, humic acids were found in the highest concentration in the slurry that has the highest content of ash (63.14%). 54 refs., 8 figs., 5 tabs.

  6. Inoculum density of Glomus mosseae and growth of onion plants in unsterilized bituminous coal spoil

    Khan, A.G.


    The effect of inoculum, density (number of vesicular-arbuscular mycorrhizal (VAM) propagules g/sup -1/ of inoculum) on the growth of onions (Allium cepa L.) infected by Glomus mosseae (Nicol and Gerd). Gerdemann and Trappe, Comb nov in unsterilized coal spoil containing indigenous VAM fungi, including G. mosseae, was investigated. The amount of onion roots converted to mycorrhizas by inoculant fungus, estimated by a gridline intersect method, increased with inoculum density (..gamma..0.62, P0.05) until a plateau was reached. Onion growth responses also increased significantly (P<0.05) with the amount of VAM inoculum present in the coal spoil. The initial linear relationship between inoculum propagules (MPN estimates), percent colonization of onion roots and onion shoot dry weight became quadratic as the number of infection propagules increased. VAM infection had no significant effect on root:shoot ratios. Similarly there was no significant interaction (P>0.05) between the inoculum density, VAM-colonized root mass and the onion root:shoot fresh weight ratios. The amount of the windswept bituminous coal spoil bound to VAM (presumably because of VAM external hyphae) also increased as inoculum density increased (..gamma..0.63, P<0.05). There was a stronger correlation (ga0.85, P<0.05) between the amount of spoil adhered per plant and the root fresh wt plant/sup -1/ indicating that root effects were primarily responsible for increasing spoil adherence. There were negative correlations (P<0.05) between root fresh wt plant/sup -1/ (..gamma..-0.68), inoculum density (..gamma..-0.589), percent root elngth infected (..gamma..-0.73) and the amount of spoil adhered g/sup -1/ root fresh wt. The possible exploitation of VAM in revegetation of bituminous coal spoil is discussed. 25 refs., 2 tabs.

  7. Providing Adapted Contextual Information in an Overlay Vehicular Network

    Andrés Muñoz


    Full Text Available Current vehicular networks are developed upon commercial solutions based on cellular networks (CNs or vehicular ad-hoc networks (VANETs, both present in numerous research proposals. Current approximations are not enough to cover the communication necessities of several applications at the same time, and they are not suitable for future vehicular pervasive services. The vehicular network presented in this paper fills the existent gap between solutions lacking in flexibility, mainly supported by an infrastructure deployment, and those highly local and distributed, such as sole-VANET approximations. In this manner, an overlay communication platform which can work over the CN basis has been designed and developed. This architecture is complemented by an additional support of an information system located at the infrastructure side. Moreover, since most of the information received from current notification services is not relevant for the driver, an additional subsystem has been devised to provide adapted information to users. This has been carried out by means of an ontology model which represents users' preferences and contextual information. Finally, using a whole prototype of the telematic platform, the performance of this interring process has been evaluated to point out its impact on the system operation.

  8. Ultrasonic Evaluation of Two Dissimilar Metal Weld Overlay Specimens

    Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Moran, Traci L.; Anderson, Michael T.


    Two dissimilar metal weld (DMW) pipe-to-nozzle specimens were implanted with thermal fatigue cracks in the 13% to 90% through-wall depth range. The specimens were ultrasonically evaluated with phased-array probes having center frequencies of 0.8, 1.0, 1.5, and 2.0 megahertz (MHz). An Alloy 82/182 weld overlay (WOL) was applied and the specimens were ultrasonically re-evaluated for flaw detection and characterization. The Post-WOL flaw depths were approximately 10% to 56% through-wall. This study has shown the effectiveness of ultrasonic examinations of Alloy 82/182 overlaid DMW specimens. Phased-array probes with center frequency in the 0.8- to 1.0-MHz range provide a strong coherent signal but the greater ultrasonic wavelength and larger beam spot size prevent the reliable detection of small flaws. These small flaws had nominal through-wall depths of less than 15% and length in the 50-60 mm (2-2.4 in.) range. Flaws in the 19% and greater through-wall depth range were readily detected with all four probes. At the higher frequencies, the reflected signals are less coherent but still provide adequate signal for flaw detection and characterization. A single inspection at 2.0 MHz could provide adequate detection and sizing information but a supplemental inspection at 1.0 or 1.5 MHz is recommended.

  9. Computing a single cell in the overlay of two simple polygons

    Berg, M. de; Devillers, O.; Dobrindt, K.T.G.; Schwarzkopf, O.


    This note combines the lazy randomized incremental construction scheme with the technique of \\connectivity acceleration" to obtain an O ( n (log ? n ) 2 ) time randomized algorithm to compute a single face in the overlay oftwo simple polygons in the plane.

  10. Digitizing geographic data with GRIDOT; a generalized program for drawing overlay grids in various map projections

    The GRIDOT computer program draws overlay grids on a Calcomp plotter for use in digitizing information from maps, rectified aerial photographs, and other sources of spatially distributed data related to regional environmental problems. The options of the program facilitate use of the overlays with standard maps and map projections of the continental United States. The overlay grid may be defined as a latitude-longitude grid (geodetic grid), a Universal Transverse Mercator Grid, or one of the standard state-plane coordinate system grids. The map for which the overlay is intended may be in an Albers Equal Area projection, a Lambert Conformal projection, a Polyconic projection, a Transverse Mercator projection, a Universal Transverse Mercator projection, or any of the standard state-plane projections

  11. 3D Finite Element Analysis of HMA Overlay Mix Design to Control Reflective Cracking

    Ghauch, Ziad G


    One of the most common rehabilitation techniques of deteriorated pavements is the placement of an HMA overlay on top of the existing Asphalt Concrete (AC) or Portland Cement Concrete (PCC) pavement. However, shortly after pavement resurfacing, HMA overlays exhibit a cracking pattern similar to that of the underlying pavement. This phenomenon is known as reflective cracking. This study examines the effectiveness of several HMA overlay mix design strategies for the purpose of controlling the development of reflective cracking. A parametric study was conducted using a 3D Finite Element (FE) model of a rigid pavement section including a Linear Viscoelastic (LVE) model for Hot Mix Asphalt (HMA) materials and non-uniform tire-pavement contact stresses. Results obtained show that for the intermediate and surface courses, using a Dense Graded (DG) or Polymer Modified (PM) asphalt mixture instead of a Standard Binder (SB) mixture results in reduced tensile stresses at the bottom of the HMA overlay but higher levels of...

  12. Analysis of mechanical tensile properties of irradiated and annealed RPV weld overlay cladding

    Mechanical tensile properties of irradiated and annealed outer layer of reactor pressure vessel weld overlay cladding, composed of Cr19Ni10Nb alloy, have been experimentally determined by conventional tensile testing and indentation testing. The constitutive properties of weld overlay cladding are then modelled with two homogenization models of the constitutive properties of elastic-plastic matrix-inclusion composites; numerical and experimental results are then compared. 10 refs., 4 figs., 4 tabs

  13. Prosthodontic management of worn dentition in pediatric patient with complete overlay dentures: a case report

    Kumar, Prince; Rastogi, Jyoti; Jain, Chandni; Singh, Harkanwal Preet


    Overlay complete dentures are simple, reversible and economical treatment modality for patients with congenital or acquired disorders that severely affect the tooth development. It satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated. In pediatric patients, the overlay dentures establish a relatively stable occlusion that improves patient's tolerance to the future treatment procedures for worn dentition. This clinical report highlights th...

  14. A Peer-to-Peer SIP System based on Service-Aware Transport Overlays

    Stiemerling, M.; Brunner, M.


    The Session Initiation Protocol (SIP) traditionally establishes and manages its sessions with centralized servers, which have been challenged by issues with TCP/IP networks right from its beginning, for instance, issues with NAT traversal or network congestions. On the other hand, there are peer-to-peer and overlay techniques that potentially can make SIP working better under various network conditions. Overlay networks can provide a good abstraction from the real network, t...

  15. RIAPPA: a robust identity assignment protocol for P2P overlays

    Caubet Fernández, Juan; Esparza Martín, Óscar; Muñoz Tapia, José Luis; Alins Delgado, Juan José; Mata Diaz, Jorge


    Peer-to-peer (P2P) overlay networks have been proposed to solve routing problems of big distributed infrastructures, even for Internet scale. But the research community has been questioning the security of these networks for years. Most prior work in security services was focused on trust and reputation systems, anonymity, and secure routing. However, the proper management of identities in overlays is an important prerequisite to provide most of these security services. In this paper, we prop...

  16. Assessment and prediction of drying shrinkage cracking in bonded mortar overlays

    Beushausen, Hans, E-mail:; Chilwesa, Masuzyo


    Restrained drying shrinkage cracking was investigated on composite beams consisting of substrate concrete and bonded mortar overlays, and compared to the performance of the same mortars when subjected to the ring test. Stress development and cracking in the composite specimens were analytically modeled and predicted based on the measurement of relevant time-dependent material properties such as drying shrinkage, elastic modulus, tensile relaxation and tensile strength. Overlay cracking in the composite beams could be very well predicted with the analytical model. The ring test provided a useful qualitative comparison of the cracking performance of the mortars. The duration of curing was found to only have a minor influence on crack development. This was ascribed to the fact that prolonged curing has a beneficial effect on tensile strength at the onset of stress development, but is in the same time not beneficial to the values of tensile relaxation and elastic modulus. -- Highlights: •Parameter study on material characteristics influencing overlay cracking. •Analytical model gives good quantitative indication of overlay cracking. •Ring test presents good qualitative indication of overlay cracking. •Curing duration has little effect on overlay cracking.

  17. Application Oriented Flow Routing Algorithm for VoIP Overlay Networks

    Wipusitwarakun, Komwut; Chimmanee, Sanon

    Overlay networks which are dynamically created over underlying IP networks are becoming widely used for delivering multimedia contents since they can provide several additional user-definable services. Multiple overlay paths between a source-destination overlay node pair are designed to improve service robustness against failures and bandwidth fluctuation of the underlying networks. Multimedia traffic can be distributed over those multiple paths in order to maximize paths' utilization and to increase application throughputs. Most of flow-based routing algorithms consider only common metrics such as paths' bandwidth or delay, which may be effective for data applications but not for real-time applications such as Voice over IP (VoIP), in which different levels of such performance metrics may give the same level of the performance experienced by end users. This paper focuses on such VoIP overlay networks and proposes a novel alternative path based flow routing algorithm using an application-specific traffic metric, i.e. “VoIP Path Capacity (VPCap), ” to calculate the maximum number of QoS satisfied VoIP flows which may be distributed over each available overlay path at a moment. The simulation results proved that more QoS-satisfied VoIP sessions can be established over the same multiple overlay paths, comparing to traditional approaches.

  18. Longitude magneto optical Kerr effect of Fe/GaAs (0 0 1) with Al overlayers

    The longitude magneto optical Kerr effect (LMOKE) is investigated on ultrathin Fe film grown on GaAs (0 0 1) substrate with Al overlayer. The formula of the longitude magneto optical Kerr effect is derived to find out the influence of the Al overlayer on the magneto optical properties of Fe/GaAs (0 0 1) sample. Results obtained from this formula fit very well with the experimental data. The change of the Kerr rotation as a function of the incident angle is also given, which can be used to find a proper angle in sample measurement. A numerical simulation was carried out to find out the relation between Kerr rotation and optical properties of the overlayer. Results from this simulation can be used to select the best overlayer material to protect the Fe/GaAs (0 0 1) sample. - Highlights: → LMOKE is investigated on Al/Fe/GaAs for the first time. → Influence of the overlayer on the properties of the sample is investigated. → Method is given to select the best overlayer material to protect the sample. → Method is given to find a proper incident angle in sample measurement.

  19. Assessment and prediction of drying shrinkage cracking in bonded mortar overlays

    Restrained drying shrinkage cracking was investigated on composite beams consisting of substrate concrete and bonded mortar overlays, and compared to the performance of the same mortars when subjected to the ring test. Stress development and cracking in the composite specimens were analytically modeled and predicted based on the measurement of relevant time-dependent material properties such as drying shrinkage, elastic modulus, tensile relaxation and tensile strength. Overlay cracking in the composite beams could be very well predicted with the analytical model. The ring test provided a useful qualitative comparison of the cracking performance of the mortars. The duration of curing was found to only have a minor influence on crack development. This was ascribed to the fact that prolonged curing has a beneficial effect on tensile strength at the onset of stress development, but is in the same time not beneficial to the values of tensile relaxation and elastic modulus. -- Highlights: •Parameter study on material characteristics influencing overlay cracking. •Analytical model gives good quantitative indication of overlay cracking. •Ring test presents good qualitative indication of overlay cracking. •Curing duration has little effect on overlay cracking

  20. EVM as Generic QOS Trigger for Heterogeneous Wireless Overlay Networks

    Rajender Kumar


    Full Text Available Fourth Generation (4G Wireless System will integrate heterogeneous wireless overlay systems i.e.interworking of WLAN/ GSM/ CDMA/ WiMAX/ LTE/ etc with guaranteed Quality of Service (QoS andExperience (QoE.QoS(E vary from network to network and is application sensitive. User needs anoptimal mobility solution while roaming in Overlaid wireless environment i.e. user could seamlesslytransfer his session/ call to a best available network bearing guaranteed Quality of Experience. And If thisSeamless transfer of session is executed between two networks having different access standards then it iscalled Vertical Handover (VHO. Contemporary VHO decision algorithms are based on generic QoSmetrics viz. SNR, bandwidth, jitter, BER and delay. In this paper, Error Vector Magnitude (EVM isproposed to be a generic QoS trigger for VHO execution. EVM is defined as the deviation of inphase/quadrature (I/Q values from ideal signal states and thus provides a measure of signal quality. In 4GInteroperable environment, OFDM is the leading Modulation scheme (more prone to multi-path fading.EVM (modulation error properly characterises the wireless link/ channel for accurate VHO decision.EVM depends on the inherent transmission impairments viz. frequency offset, phase noise, non-linearimpairment,skewness etc. for a given wireless link. Paper provides an insight to the analytical aspect ofEVM & measures EVM (% for key management subframes like association/re-association/disassociation/probe request/response frames. EVM relation is explored for different possible NAV-Network AllocationVectors (frame duration. Finally EVM is compared with SNR, BER and investigation concludes EVM as apromising QoS trigger for OFDM based emerging wireless standards.

  1. The effect of petrographical composition of coals and bituminous sediments on the material and isotopic composition of dry natural gases from artificial recoalification reactions. 2

    Experimental results indicate that on the basis of the material and isotopic composition of natural gases conclusions can be drawn with regard to the character (humic or bituminous) of the parent rock. Thus, genetic relations assumed to exist between humic sediments (e.g. coal seams) and dry natural gases as well as bituminous rocks and wet natural gases are experimentally confirmed. In addition, from analyses of the materials approximate data can be derived on the degree of carbonization of coal or bituminous sediments in the main phase of gas separation. Furthermore, these analyses were used to elucidate the question whether authochthonous or allochthonous deposits are present. It could be shown that the maceral composition of coals and of the organo-petrographical inclusions in bituminous sediments determines the isotopic composition of methane in recoalification gases to a considerable degree. (author)

  2. Minimization of total overlay errors on product wafers using an advanced optimization scheme

    Levinson, Harry J.; Preil, Moshe E.; Lord, Patrick J.


    The matching of wafer steppers is accomplished typically by patterning two successive layers, using different steppers of interest for each layer, and measuring the overlay at many points in the exposure field. Matching is considered to be optimized when some metric, such the sum-of-squares of overlay errors, is minimized over all measured points within the field. This is to be contrasted to the situation which arises during the in-line measurement of overlay errors in production, where a far more limited sampling of points is involved. There are several consequences to limited sampling. Adjustable intrafield overlay components, such as magnification, may appear to vary up to several parts-per- million as a consequence of varying chip size. These variations are substantially larger than the normal variations of these components for fixed field sizes, and so have significant consequences for the application of statistical methodologies to the control of overlay components. The width of the distribution of overlay errors across the field may typically increase between 10 to 20 nm (3(sigma) ), with even larger increases in mean shifts, all varying with field size. Reticles may also introduce similar variations, both random and systematic. Reticle beam-writer errors lead to systematic intrafield errors, particularly asymmetric field magnification and field skew. Steppers may compensate for these systematic reticle errors, and step- and-scan systems are more effective at this compensation than step-and-repeat machines. For steppers which have process dependent alignment, this compensation must be determined on products, which leads back to the problems associated with limited sampling. Correction for the overlay errors induced by limited sampling may be accomplished by look-up tables incorporated into the overlay analysis software. For each pair of steppers and each sampling plan, corrections can be applied at each measurement point in order to bring the full field and

  3. Study on the cause of the fire and explosion incident at Bituminization Demonstration Facility of PNC Tokai Works

    On March 11, 1997, a fire and explosion incident occurred in Bituminization Demonstration Facility (BDF) at Tokai Reprocessing Plant (TRP). The cause of the incident was thoroughly investigated and after thirty meetings of 'Investigation Committee of Science and Technology Agency (STA)'. STA reported possible cause of this incident. Continually detailed investigation was discussed at 'Follow-up Committee of STA'. Based on the results of five meetings, JNC concluded that the main cause of fire was frictional heating and viscous heating in the extruder, which provided an unusually high temperature in the bituminized product at filling, since there was no chemical analysis data suggesting the generation of chemical heat. It is considered that these excessive heat generations were due to the decreased feed rate of liquid waste to the extruder. The Follow-up Committee almost agreed to this conclusion. This paper describes general information concerning the incident and details of the cause of the incident. (author)

  4. Effect of organic calcium compounds on combustion characteristics of rice husk, sewage sludge, and bituminous coal: thermogravimetric investigation.

    Zhang, Lihui; Duan, Feng; Huang, Yaji


    Experiments were conducted in a thermogravimetric analyzer to assess the enhancement of combustion characteristics of different solid fuels blended with organic calcium compounds (OCCs). Rice husk, sewage sludge, and bituminous coal, and two OCC were used in this study. Effect of different mole ratios of calcium to sulfur (Ca/S ratio) on the combustion characteristics were also investigated. Results indicated that combustion performance indexes for bituminous coal impregnated by OCC were improved, however, an inverse trend was found for sewage sludge because sewage sludge has lower ignition temperature and higher volatile matter content compared to those of OCC. For rice husk, effect of added OCC on the combustion characteristics is not obvious. Different solid fuels show different combustion characteristics with increases of Ca/S ratio. The maximum combustion performance indexes appear at Ca/S ratios of 1:1, 2:1, and 3:1 for OCC blended with Shenhua coal, rice husk, and sewage sludge, respectively. PMID:25638405

  5. The bituminization in Marcoule and la Hague plants. Description of the processes and the fire risk prevention

    Chemical precipitation is an efficient process to decontaminate liquid effluents and has been selected as early as 1966 for the liquid waste treatment of MARCOULE. The process has been designed by the French CEA and improved along the time. The first implementation in LA HAGUE was for the STE 2 facility (Station de Traitement d'Effluents no 2). A new facility, STE 3, has been commissioned in 1989 in LA HAGUE, benefiting from these previous experience and therefore contributing into a drastic reduction of liquid discharges. The sludges coming from the treatment in MARCOULE and STE 3 are bituminized into continuous extruders. The resulting waste is kept in interim storage, waiting for final disposal. The industrial production, up to now, is close to 10000 drums (55 gallons) in LA HAGUE and 60000 drums in MARCOULE. A retrieval operation of the MARCOULE drums from the present storage has been launched to send them into a recently built interim storage operating since the beginning of 2000. At the present time, in LA HAGUE, evaporation has been preferred to chemical precipitation for the treatment of liquid effluents. After concentration, the effluents go to the vitrification and the volume of resulting waste is much smaller. However, bituminization is still the preferred option for the 10000 m3 of sludges resulting from the STE 2 operations which are being stored in tanks. A complete reevaluation of the operation safety measures of bituminization has been made lately in both plants following recent incidents on other installations. The paper describes the chemical precipitation and the bituminization processes and focuses on safety measures which are implemented for prevention, detection and fight. (authors)

  6. Dye-adsorption capacity of bituminous fly ash and its pozzolanic property after used as dye-adsorbent

    Penpolcharoen, M.


    Bituminous fly ash, which is an industrial waste, was used as an adsorbent to remove dyestuff from the textile-dye wastewater. The batch kinetic and isotherm experiments of the synthetic wastewater were firstly conducted to determine the adsorption behavior and optimal conditions for adsorption. The optimal conditions were then applied to the actual textile-dye wastewater. Under the original conditions of fly ash and wastewater, the results indicated that the color could be removed up to 86.6...

  7. Evaluation of Tizian overlays by means of a swept source optical coherence tomography system

    Marcauteanu, Corina; Sinescu, Cosmin; Negrutiu, Meda Lavinia; Stoica, Eniko Tunde; Topala, Florin; Duma, Virgil Florin; Bradu, Adrian; Podoleanu, Adrian Gh.


    The teeth affected by pathologic attrition can be restored by a minimally invasive approach, using Tizian overlays. In this study we prove the advantages of a fast swept source (SS) OCT system in the evaluation of Tizian overlays placed in an environment characterized by high occlusal forces. 12 maxillary first premolars were extracted and prepared for overlays. The Tizian overlays were subjected to 3000 alternating cycles of thermo-cycling (from -10°C to +50°C) and to mechanical occlusal overloads (at 800 N). A fast SS OCT system was used to evaluate the Tizian overlays before and after the mechanical and thermal straining. The SS (Axsun Technologies, Billerica, MA) has a central wavelength of 1060 nm, sweeping range of 106 nm (quoted at 10 dB) and a 100 kHz line rate. The depth resolution of the system, measured experimentally in air was 10 μm. The imaging system used for this study offers high spatial resolutions in both directions, transversal and longitudinal of around 10 μm, a high sensitivity, and it is also able to acquire entire tridimensional (3D)/volume reconstructions as fast as 2.5 s. Once the full dataset was acquired, rendered high resolutions en-face projections could be produced. Using them, the overlay (i.e., cement) abutment tooth interfaces were remarked both on B-scans/two-dimensional (2D) sections and in the 3D reconstructions. Using the system several open interfaces were possible to detect. The fast SS OCT system thus proves useful in the evaluation of zirconia reinforced composite overlays, placed in an environment characterized by high occlusal forces.

  8. Utilization of Waste Clay from Boron Production in Bituminous Geosynthetic Barrier (GBR-B Production as Landfill Liner

    Müfide Banar


    Full Text Available Bituminous geomembranes, one type of geosynthetics, include a hot bituminous mixture with mineral filler and reinforcement. In this study, boron production waste clay (CW was used as filler to produce a geosynthetic barrier with bentonite, waste tire, and bitumen. Bentonite and waste tires were used as auxiliary fillers and bitumen as the binder. CW/bitumen, CW/bentonite/bitumen, and CW/waste tire/bitumen mixtures were prepared by using a laboratory mixer at 100°C. Hot mixtures were extruded into strips by using a lab-scale corotating twin screw extruder (L/D: 40 followed by die casting (2 mm × 100 mm. Glass fleece or nonwoven polyester was used as reinforcement material and while die casting, both sides of the reinforcement materials were covered with bituminous mixture. Thickness, mass per unit area, tensile strength, elongation at yield, and hydraulic conductivity were used to characterize the geomembranes. Among all geomembranes, nonwoven polyester covered with 30% bitumen-70% boron waste clay mixture (PK-BTM30CW70 was found to be the most promising in terms of structure and mechanical behaviour. After that, consequences of its exposure to distilled water (DW, municipal solid waste landfill leachate (L-MSW, and hazardous waste landfill leachate (L-HW were examined to use for an innovative impermeable liner on solid waste landfills.

  9. A preliminary investigation into the physical and chemical properties of biomass ashes used as aggregate fillers for bituminous mixtures.

    Melotti, Roberto; Santagata, Ezio; Bassani, Marco; Salvo, Milena; Rizzo, Stefano


    Fly and bottom ashes are the main by-products arising from the combustion of solid biomass. Since the production of energy from this source is increasing, the processing and disposal of the resulting ashes has become an environmental and economic issue. Such ashes are of interest as a construction material because they are composed of very fine particles similar to fillers normally employed in bituminous and cementitious mixtures. This research investigates the potential use of ash from biomass as filler in bituminous mixtures. The morphological, physical and chemical characteristics of 21 different ashes and two traditional fillers (calcium carbonate and "recovered" plant filler) were evaluated and discussed. Leaching tests, performed in order to quantify the release of pollutants, revealed that five ashes do not comply with the Italian environmental re-use limits. Experimental results show a wide range of values for almost all the investigated properties and a low correlation with biomass type in terms of origin and chemical composition. Furthermore, sieving and milling processes were found to improve the properties of the raw material in terms of grading and sample porosity. The effectiveness of these treatments and the low content of organic matter and harmful fines suggest that most of the biomass ashes investigated may be regarded as potential replacements for natural filler in bituminous mixtures. PMID:23790672

  10. Analysis and modeling of 3D complex modulus tests on hot and warm bituminous mixtures

    Pham, Nguyen Hoang; Sauzéat, Cédric; Di Benedetto, Hervé; González-León, Juan A.; Barreto, Gilles; Nicolaï, Aurélia; Jakubowski, Marc


    This paper presents the results of laboratory testing of hot and warm bituminous mixtures containing Reclaimed Asphalt Pavement (RAP). Complex modulus measurements, using the tension-compression test on cylindrical specimens, were conducted to determine linear viscoelastic (LVE) behavior. Sinusoidal cyclic loadings, with strain amplitude of approximately 50ṡ10-6, were applied at several temperatures (from -25 to +45 °C) and frequencies (from 0.03 Hz to 10 Hz). In addition to axial stresses and strains, radial strains were also measured. The complex modulus E ∗ and complex Poisson's ratios ν ∗ were then obtained in two perpendicular directions. Measured values in these two directions do not indicate anisotropy on Poisson's ratio. The time-temperature superposition principle (TTSP) was verified with good approximation in one-dimensional (1D) and three-dimensional (3D) conditions for the same values of shift factor. Experimental results were modeled using the 2S2P1D model previously developed at the University of Lyon/ENTPE. In addition, specific analysis showed that eventual damage created during complex modulus test is very small and is equivalent to the effect of an increase of temperature of about 0.25 °C.

  11. Contribution to physico-chemical study of Timahdit bituminous schists (Morocco): Organic matters and metalloporphyrins

    The Timahdit bituminous schists have been analysed by different methods. The experimental results obtained using these methods concern the behaviour of the schists and the Kerogen facing the pyrolysis, as well as the separation of the hydrocarbons and the metalloporphyrins. For this purpose the techniques used are: 'Rock Eval' pyrolysis, thermogravimetric analysis and electron paramagnetic resonance (E.P.R.) for the raw rock and the Kerogen; infrared (I.R.), gas chromatography and E.P.R. for the extracted organic matters; E.P.R., I.R., nuclear magnetic resonance (N.M.R.), ultraviolet (U.V.) and mass spectrometry for the metalloporphyrins identification and characterization. The analysis of these schists has shown that: We can extract per solvent only 1% of organic matters, ferric oxide hasn't any effect neither on the pyrolysis nor on the organic matters extraction and that the Kerogen of these schists are relatively rich in hydrocarbonic compounds. The gas chromatography reveal the presence of alkanes with odd number of carbons and isoprenoids. All these criteria indicate an immature, little developped organic matter which having probably a marine origin but possessing a good oil potential. It has also been observed that a part of Iron, Nickel and Vanadium in the schists are incorporated into the organic matters. Nickel and Vanadium are into macrocycles which are porphyrins. A method for extracting and separating these porphyrins has been developped. 43 figs., 21 tabs., 58 refs. (author)

  12. Influence of Extrusion Conditions on the Rheological Behavior of Nuclear Bituminized Waste Products

    In France, bitumen has been used since four decades as a container material for low/intermediate activity and long lifetime radionuclides. Industrial Bituminized Waste Products (BWP) are produced by continuous extrusion of 60 wt.% bitumen and 40 wt.% salts, in which a very small fraction is radioactive. These incorporated salts are, in majority, of two types: soluble or insoluble. During storage, the organic matrix subjected to irradiation produces gases, which can give rise to BWP swelling in the container and then to a possible overflow. The extent of gas production is directly linked to the degree of dispersion of the salts into the bitumen matrix. To quantify this dispersion, the effect of extrusion operating conditions, such as feed rate and screw speed, have been studied using a laboratory scale co-rotating twin screw extruder. BWP rheological characterization shows the development of a pseudo-solid plateau at low frequency and a change in the linear viscoelastic domain when screw speed and feed rate are varied, indicating a modification of the dispersion state. Samples characterization with environmental scanning electron microscopy (ESEM) confirms in the case of insoluble and soluble salts a change in the number of agglomerates, accompanied by an improvement of the dispersion at high screw speed but less remarkable with the feed rate. A Carreau-Yasuda law with a yield stress is proposed to describe the theological behaviour of these materials. The effects of volume fraction and maximum volume fraction on viscosity are described using a Krieger-Dougherty equation. (authors)

  13. Development of a method to determine the nuclide inventory in bituminized waste packages

    Until the 1980s, bitumen was used as a conditioning agent for weak to medium radioactive liquid waste. Its use can be ascribed mainly to the properties that indicated that the matrix was optimal. However, fires broke out repeatedly during the conditioning process, so that the method is meanwhile no longer permitted in Germany. There are an estimated 100 waste packages held by the public authorities in Germany that require a supplementary declaration. In contrast to the common matrices, such as for example resins or sludges, there is still no standardized technology for taking samples and subsequently determining the radio-nuclide for bitumen. Aspects, such as the thermoplastic behaviour, make determining the nuclide inventory more difficult in bituminized waste packages. The development of a standardized technology to take samples with a subsequent determination of the radio-nuclide analysis is the objective of a project funded by the BMBF. Known, new methods, specially developed for the project, are examined on inactive bitumen samples and then transferred to active samples. At first non-destructive methods are used. The resulting information forms an important basis to work out and apply destructive strategy for sampling and analysis. Since the project is on-going, this report can only address the development of the sampling process. By developing a sampling system, it will be possible to take samples from an arbitrary selected location of the package across the entire matrix level and thus gain representative analysis material. The process is currently being optimized. (orig.)

  14. Elemental analysis of Indonesian and Australian bituminous coal used at Kapar Power Station

    An instrumental neutron activation analytical (INAA) technique is used for the determination of thirty elements in five coal samples collected from Kapar power station, imported from Indonesia and Australia. Analyses of the samples are being associated with standards. All irradiation were performed in the nuclear reactor of Malaysia Nuclear Agency (MNA). samples were counted by Hyper Pure Germanium (HPGe) detector for short period irradiations at MNA, while for the long period irradiations the samples were counted at Universiti Kebangsaan Malaysia (UKM). The concentrations of thirty elements have been determined: The major components are Cl, Ca, Mg, K, Fe, Ti, and Na with the mean concentrations in the range between 70±69 ppm-6100±1639 ppm; and the trace elements are Zr, V, Mn, Sc, Cr, Co, As, Br, Rb, Sb, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Th, U and Ta with the mean concentrations in the range between 0.1381±0.0202 - 69.0±2.8 ppm. The results have been compared to the reported data of eight coal samples from the United States and the reported data of Australian bituminous coal. (Author)

  15. Using proximate analysis to characterize airborne dust generation from bituminous coals

    Page, S.J.; Organiscak, J.A.


    Prolonged exposure to airborne respirable coal dust is responsible for coal workers pneumoconiosis (CWP), commonly called black lung. Health research studies have identified that the prevalence and severity of CWP are directly related to both the amount of dust exposure and the coal rank. The amount of airborne respirable dust (ARD) smaller than 10 micrometers generated from breakage of different coals varies widely. To investigate the cause, researchers for the National Institute for Occupational Safety and Health (NIOSH) have conducted experiments to identify the causes of airborne respirable dust liberation. Laboratory crushing experiments were conducted on a range of low to high volatile bituminous coals from eight mines. The results indicate that the proximate analysis of a coal sample can provide a very good indicator of the potential for a dust problem. For application to the coal mining, processing, and utilization industries, data from 977 US coal seams compiled by the Department of Energy (DoE) has been used to calculate this dust generation potential from an equation based on the NIOSH measured data. A simple procedure for this calculation is provided. 1 fig.

  16. Burnout behaviour of bituminous coals in air-staged combustion conditions

    Kluger, F.; Spliethoff, H.; Hein, K.R.G. [University of Stuttgart, Stuttgart (Germany). Inst. of Process Engineering and Power Plant (IVD)


    In order to determine the influence on burnout by the combustion conditions and the coal preparation, three bituminous coals sold on the world market, from three different locations in Poland, South Africa, and Australia, were studied more closely. For this purpose, the coals were ground in two different particle size ranges, which, besides the influence of the combustion conditions, such a temperature, residence time, and stoichiometry, made it possible to also investigate the impact on burnout by the coal preparation. The experiments were carried out in an electrically heated entrained-flow reactor with a thermal input of 8.5 kW. The parameters for the experiments are wall temperature (1000-1350{degree}C), air ratio (0.6-1.15) and two particle sizes (70% {lt} 75 {mu}m, 90% {lt} 75 {mu}m). The results show that in general, for increasing temperatures, the burnout quality will improve. For the Australian Illawara coal, another outcome is increased NOx emissions. Lowering the air ratio in the reduction zone leads to less NOx emission but to increased unburnt matter in ash. For the smaller particle size fraction, the analysis of the different particle sizes shows an improvement of the burnout without a change in NOx emissions. 10 refs., 10 figs., 2 tabs.

  17. Recycling of polyethylene terephthalate (PET plastic bottle wastes in bituminous asphaltic concrete

    Adebayo Olatunbosun Sojobi


    Full Text Available This research sheds light on the concept of eco-friendly road construction which comprises eco-design, eco-extraction, eco-manufacturing, eco-construction, eco-rehabilitation, eco-maintenance, eco-demolition, and socioeconomic empowerment. It also revealed the challenges being faced in its adoption and the benefits derivable from its application. Furthermore, the effects of recycling PET plastic bottle wastes produced in North Central Nigeria in bituminous asphaltic concrete (BAC used in flexible pavement construction were also evaluated. The mix design consists of 60/70 penetration-grade asphaltic concrete (5%, 68% coarse aggregate, 6% fine aggregate, and 21% filler using the dry process at 170°C. The optimum bitumen content (OBC for conventional BAC was obtained as 4% by weight of total aggregates and filler. Polymer-coated aggregate (PCA-modified BAC seems preferable because it has the potential to utilize more plastic wastes with a higher optimum plastic content (OPC of 16.7% by weight of total aggregates and filler compared to that of 9% by weight of OBC achieved by PMB-BAC. For both PMB- and PCA-modified BAC, an increase in air void, void in mineral aggregate, and Marshall stability were observed. Eco-friendly road construction which recycles PET wastes should be encouraged by government considering its potential environmental and economic benefits.

  18. Effect of Fe content on the friction and abrasion properties of copper base overlay on steel substrate by TIG welding

    Lü Shixiong; Song Jianling; Liu Lei; Yang Shiqin


    Copper base alloy was overlaid onto 35CrMnSiA steel plate by tungsten inert gas (TIG) welding method. The heat transfer process was simulated, the microstructures of the copper base overlay were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the friction and abrasion properties of the overlay were measured. The results show that the Fe content increases in the overlay with increasing the welding current. And with the increase of Fe content in the overlay, the friction coefficient increases and the wear mechanism changes from oxidation wear to abrasive wear and plough wear, which is related to the size and quantity of Fe grains in the overlay. While with the increase of Fe content in the overlay, the protection of oxidation layer against the oxidation wear on the melted metal decreases.

  19. Characterisation of hydrocarbonaceous overlayers important in metal-catalysed selective hydrogenation reactions

    Lennon, David; Warringham, Robbie [School of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Guidi, Tatiana [ISIS Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Parker, Stewart F., E-mail: [ISIS Facility, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom)


    Highlights: • Inelastic neutron scattering spectroscopy of a commercial dehydrogenation catalyst. • The overlayer present on the catalyst is predominantly aliphatic. • A population of strongly hydrogen bonded hydroxyls is also present. - Abstract: The hydrogenation of alkynes to alkenes over supported metal catalysts is an important industrial process and it has been shown that hydrocarbonaceous overlayers are important in controlling selectivity profiles of metal-catalysed hydrogenation reactions. As a model system, we have selected propyne hydrogenation over a commercial Pd(5%)/Al{sub 2}O{sub 3} catalyst. Inelastic neutron scattering studies show that the C–H stretching mode ranges from 2850 to 3063 cm{sup −1}, indicating the mostly aliphatic nature of the overlayer and this is supported by the quantification of the carbon and hydrogen on the surface. There is also a population of strongly hydrogen-bonded hydroxyls, their presence would indicate that the overlayer probably contains some oxygen functionality. There is little evidence for any olefinic or aromatic species. This is distinctly different from the hydrogen-poor overlayers that are deposited on Ni/Al{sub 2}O{sub 3} catalysts during methane reforming.

  20. Information Exchange rather than Topology Awareness: Cooperation between P2P Overlay and Traffic Engineering

    Jia Zhao


    Full Text Available Solutions to the routing strategic conflict between noncooperative P2P overlay and ISP underlay go separate ways: hyperselfishness and cooperation. Unpredictable (possibly adverse impact of the hyperselfish topology awareness, which is adopted in both overlay routing and traffic engineering, has not been sufficiently studied in the literature. Topology-related information exchange in a cooperatively efficient way should be highlighted to alleviate the cross-layer conflict. In this paper, we first illustrate the hyperselfish weakness with two dynamic noncooperative game models in which hyperselfish overlay or underlay has to accept a suboptimal profit. Then we build a synergistic cost-saving (SC game model to reduce the negative effects of noncooperation. In the SC model, through information exchange, that is, the classified path-delay metrics for P2P overlay and peer locations for underlay, P2P overlay selects proximity as well as saving traffic transit cost for underlay, and ISP underlay adjusts routing to optimize network cost as well as indicating short delay paths for P2P. Simulations based on the real and generated topologies validate cost improvement by SC model and find a proper remote threshold value to limit P2P traffic from remote area, cross-AS, or cross-ISP.

  1. In die mask overlay control for 14nm double-patterning lithography

    Chou, William; Cheng, James; Tseng, Alex C. P.; Wu, J. K.; Chang, Chin Kuei; Cheng, Jeffrey; Lee, Adder; Huang, Chain Ting; Peng, N. T.; Hsu, Simon C. C.; Yu, Chun Chi; Lu, Colbert; Yu, Julia; Craig, Peter; Pollock, Chuck; Ham, Young; McMurran, Jeff


    According to the ITRS roadmap, semiconductor industry drives the 193nm lithography to its limits, using techniques like Double Pattern Technology (DPT), Source Mask Optimization (SMO) and Inverse Lithography Technology (ILT). In terms of considering the photomask metrology, full in-die measurement capability is required for registration and overlay control with challenging specifications for repeatability and accuracy. Double patterning using 193nm immersion lithography has been adapted as the solution to enable 14nm technology nodes. The overlay control is one of the key figures for the successful realization of this technology. In addition to the various error contributions from the wafer scanner, the reticles play an important role in terms of considering lithographic process contributed errors. Accurate pattern placement of the features on reticles with a registration error below 4nm is mandatory to keep overall photomask contributions to overlay of sub 20nm logic within the allowed error budget. In this paper, we show in-die registration errors using 14nm DPT product masks, by measuring in-die overlay patterns comparing with regular registration patterns. The mask measurements are used to obtain an accurate model to predict mask contribution on wafer overlay of double patterning technology.

  2. Residual stress determination in a dissimilar weld overlay pipe by neutron diffraction

    Highlights: → Determined residual stress distribution in a dissimilar weld overlay pipe. → Consists of a ferritic (SA508), austenitic (F316L) steels, Alloy 182 consumable. → Measured significant compression (-600 MPa) near the inner wall of overlay. → Validate integrity of the inner wall for the pressurized nozzle nuclear structure. - Abstract: Residual stresses were determined through the thickness of a dissimilar weld overlay pipe using neutron diffraction. The specimen has a complex joining structure consisting of a ferritic steel (SA508), austenitic steel (F316L), Ni-based consumable (Alloy 182), and overlay of Ni-base superalloy (Alloy 52M). It simulates pressurized nozzle components, which have been a critical issue under the severe crack condition of nuclear power reactors. Two neutron diffractometers with different spatial resolutions have been utilized on the identical specimen for comparison. The macroscopic 'stress-free' lattice spacing (do) was also obtained from both using a 2-mm width comb-like coupon. The results show significant changes in residual stresses from tension (300-400 MPa) to compression (-600 MPa) through the thickness of the dissimilar weld overlay pipe specimen.

  3. A Measurement Study of the Structured Overlay Network in P2P File-Sharing Systems

    Mo Zhou


    Full Text Available The architecture of P2P file-sharing applications has been developing to meet the needs of large scale demands. The structured overlay network, also known as DHT, has been used in these applications to improve the scalability, and robustness of the system, and to make it free from single-point failure. We believe that the measurement study of the overlay network used in the real file-sharing P2P systems can provide guidance for the designing of such systems, and improve the performance of the system. In this paper, we perform the measurement in two different aspects. First, a modified client is designed to provide view to the overlay network from a single-user vision. Second, the instances of crawler programs deployed in many nodes managed to crawl the user information of the overlay network as much as possible. We also find a vulnerability in the overlay network, combined with the character of the DNS service, a more serious DDoS attack can be launched.

  4. Implementation and benefits of advanced process control for lithography CD and overlay

    Zavyalova, Lena; Fu, Chong-Cheng; Seligman, Gary S.; Tapp, Perry A.; Pol, Victor


    Due to the rapidly reduced imaging process windows and increasingly stingent device overlay requirements, sub-130 nm lithography processes are more severely impacted than ever by systamic fault. Limits on critical dimensions (CD) and overlay capability further challenge the operational effectiveness of a mix-and-match environment using multiple lithography tools, as such mode additionally consumes the available error budgets. Therefore, a focus on advanced process control (APC) methodologies is key to gaining control in the lithographic modules for critical device levels, which in turn translates to accelerated yield learning, achieving time-to-market lead, and ultimately a higher return on investment. This paper describes the implementation and unique challenges of a closed-loop CD and overlay control solution in high voume manufacturing of leading edge devices. A particular emphasis has been placed on developing a flexible APC application capable of managing a wide range of control aspects such as process and tool drifts, single and multiple lot excursions, referential overlay control, 'special lot' handling, advanced model hierarchy, and automatic model seeding. Specific integration cases, including the multiple-reticle complementary phase shift lithography process, are discussed. A continuous improvement in the overlay and CD Cpk performance as well as the rework rate has been observed through the implementation of this system, and the results are studied.

  5. Performance polymeric concrete with synthetic fiber reinforcement against reflective cracking in rigid pavement overlay

    Cement concrete pavements are used for heavy traffic loads throughout the world owing to its better and economical performance. Placing of a concrete overlay on the existing pavement is the most prevalent rehabilitating method for such pavements, however, the problem associated with the newly placed overlay is the occurrence of reflective cracking. This paper presents an assessment of the performance of polymeric concrete with synthetic fiber reinforcement against reflective cracking in an overlay system. The performance of polymeric concrete with synthetic fibers as an overlay material is measured in terms of the load-deflection, strain-deflection and load-strain behavior of beams of the polymeric concrete. For this purpose, five types of beams having different number of fiber wires and position are tested for flexure strength. Deflection/strains for each increment of load are recorded. In addition, cubes of plain concrete and of concrete with synthetic fiber needles were tested after 7 and 28 days for compressive strengths. Finite element models in ANSYS software for the beams have also been developed. Beams with greater number of longitudinal fiber wires displayed relatively better performance against deflection whilst beams with synthetic fiber needles showed better performance against strains. Thus, polymeric concrete overlay with fiber reinforcement will serve relatively better against occurrence of reflective cracking. (author)

  6. Desarrollo de sistemas y servicios de información sobre redes overlay peer-to-peer

    Muñoz Gea, Juan Pedro


    [SPA] Una red overlay es una red virtual de nodos y enlaces lógicos construida sobre la red Internet. Por lo tanto, las redes overlay se pueden ver como una capa intermedia situad entre los protocolos básicos de Internet y el nivel de aplicación. Para entender por qué las redes overlay son importantes y el papel que desempeñan, merece la pena considerar las distintas razones que han motivado su aparición. En primer lugar, las redes overlay pueden utilizarse para soportar los requisitos especi...

  7. Study on the rupture characteristics of the overlaying soil with soft interlayer due to fault bedrock dislocation

    ZHAO Lei; LI Xiao-jun; HUO Da


    In this paper, the rupture characteristics of the overlaying soil with soft interlayer were studied by plane-strain finite element method. From the results, it can be shown that the existence of soft layer separates rupture process of the overlaying soil into two phases. The depth of a buried soft interlayer will influence the rupture process and the rupture range of the overlaying soil. The deeply buried soft interlayer would bring about a wider range of surface failure. In addition, the thickness of the soft layer also has effect on the rupture process and rupture range of the overlaying soil.

  8. Alloying effects on hydrogen permeability of V without catalytic Pd overlayer

    Nakamura, Y.; Yukawa, H.; Suzuki, A. [Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan); Nambu, T. [Department of Materials Science and Engineering, Suzuka National College of Technology, Shiroko-cho, Suzuka, Mie 510-0294 (Japan); Matsumoto, Y. [Department of Mechanical Engineering, Oita National College of Technology, Maki, Oita 870-0152 (Japan); Murata, Y. [Department of Materials Science and Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan)


    Highlights: • Air–treated V–based alloy membranes without catalytic Pd overlayer are found to possess excellent hydrogen permeability. • They also exhibit good durability at high temperature. • Alloying effects are discussed in view of the new description of hydrogen permeation based on hydrogen chemical potential. - Abstract: Hydrogen permeability of air–treated V–based alloy membranes without Pd coating have been investigated. The diffusion–limiting hydrogen permeation reaction takes place even without catalytic Pd overlayer on the surface. It is shown that pure V and its alloy membranes without Pd overlayer possess excellent hydrogen permeability and good durability at high temperature. The new description of hydrogen permeation based on hydrogen chemical potential has been applied and the hydrogen flux is analyzed in terms of the mobility of hydrogen atom and the PCT factor, f{sub PCT}.

  9. Study on cracking of welding overlay based on the theory of diffusion-induced stress

    Xiliang ZHANG; Changyu ZHOU


    Hydrogen diffusion in the wall of hydrogenation reactor for three situations,i.e. operating,normal shutdown and abnormal shutdown,was numerically simulated based on the finite element program-ABAQUS. The formula of diffusion-induced stress was deduced for model of the thin walled cylinder. Distribution of diffusion-induced stress in the wall of hydrogenation reactor was studied. The results showed that the maximum stress was at the fusion surface between welding overlay and base metal,and which would increase with cooling rate. The crack will initiate and propagate from fusion surface to welding overlay when the diffusion-induced stress is higher than yield stress,but it will not propagate to the base metal. Diffusion-induced stress is one of the important factors for crack initiation and propagation of welding overlay of hydrogenation reactor.

  10. Effects of indium and tin overlayers on the photoluminescence spectrum of mercuric iodide

    Mercuric iodide (HgI2 ) crystals with semitransparent metal overlayers of indium and tin were characterized using low-temperature photoluminescence (PL) spectroscopy. The PL spectra were found to differ for points beneath the thin metal overlayers and points that were masked off during each deposition. The photoluminescence data were compared with PL measurements taken on HgI2 photodetectors with indium-tin-oxide (ITO) entrance electrodes. The similarities of the spectra for the HgI2 samples with In, Sn, and ITO conducting overlayers indicate that the regions in the ITO-contacted photodetectors with relatively poor photoresponses are associated with the interaction of indium or tin with the mercuric iodide substrate